US20140190669A1 - Cooling head and electronic apparatus - Google Patents
Cooling head and electronic apparatus Download PDFInfo
- Publication number
- US20140190669A1 US20140190669A1 US14/051,521 US201314051521A US2014190669A1 US 20140190669 A1 US20140190669 A1 US 20140190669A1 US 201314051521 A US201314051521 A US 201314051521A US 2014190669 A1 US2014190669 A1 US 2014190669A1
- Authority
- US
- United States
- Prior art keywords
- flow channel
- refrigerant
- refrigerant flow
- cooling head
- cooled
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F3/00—Plate-like or laminated elements; Assemblies of plate-like or laminated elements
- F28F3/08—Elements constructed for building-up into stacks, e.g. capable of being taken apart for cleaning
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
- F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
- F28D15/0266—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes with separate evaporating and condensing chambers connected by at least one conduit; Loop-type heat pipes; with multiple or common evaporating or condensing chambers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F3/00—Plate-like or laminated elements; Assemblies of plate-like or laminated elements
- F28F3/12—Elements constructed in the shape of a hollow panel, e.g. with channels
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
- H01L23/46—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements involving the transfer of heat by flowing fluids
- H01L23/473—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements involving the transfer of heat by flowing fluids by flowing liquids
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
- F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
- F28D2021/0028—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for cooling heat generating elements, e.g. for cooling electronic components or electric devices
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F2250/00—Arrangements for modifying the flow of the heat exchange media, e.g. flow guiding means; Particular flow patterns
- F28F2250/04—Communication passages between channels
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
- F28F9/02—Header boxes; End plates
- F28F9/026—Header boxes; End plates with static flow control means, e.g. with means for uniformly distributing heat exchange media into conduits
- F28F9/027—Header boxes; End plates with static flow control means, e.g. with means for uniformly distributing heat exchange media into conduits in the form of distribution pipes
- F28F9/0273—Header boxes; End plates with static flow control means, e.g. with means for uniformly distributing heat exchange media into conduits in the form of distribution pipes with multiple holes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
- H01L2924/0001—Technical content checked by a classifier
- H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
Definitions
- Embodiments discussed herein are related to a cooling head and an electronic apparatus.
- a main flow channel and a sub-flow channel for a cooling liquid are formed in this order from the side of the cooling surface.
- a plurality of nozzles that penetrate a partition wall separating the sub-flow channel and the main flow channel and that protrude into the main flow channel are arranged in the flow channel direction of the main flow channel, and tip end parts of the individual nozzles are caused to be in the vicinity of or in contact with the cooling surface.
- the cooling liquid is caused to circulate to the main flow channel and the sub-flow channel, the cooling surface is cooled with boiling of the cooling liquid flowing through the main flow channel, and the cooling liquid on the sub-flow channel side is supplied from the sub-flow channel side through each of the nozzles so as to exude in the vicinity of the cooling surface.
- a cooling head includes: a first refrigerant flow channel, provided so as to be in contact with an object to be cooled, configured to flow refrigerant; a second refrigerant flow channel configured to flow the refrigerant; and at least one communication hole, provided between both ends of the object to be cooled in the first refrigerant flow channel in a first flow direction of refrigerant in the first refrigerant flow channel, configured to allow the first refrigerant flow channel and the second refrigerant flow channel to communicate with each other.
- FIG. 1 illustrates an example of a cooling system
- FIG. 2 illustrates an example of a relationship between a cooling head and an electronic device
- FIG. 3 illustrates an example of a communication hole
- FIG. 4 illustrates an example of cooling effect
- FIG. 5 illustrates an example of a top view of a first refrigerant flow channel
- FIG. 6A and FIG. 6B each illustrate an example of a top view of the flow of refrigerant
- FIG. 7 illustrates an example of a top view of a second refrigerant flow channel and a communication hole
- FIG. 8 illustrates an example of a top view of a second refrigerant flow channel and a communication hole
- FIG. 9 illustrates an example of arrangement of a communication hole
- FIG. 10 illustrates an example of an exploded perspective view of a cooling head
- FIG. 11 illustrates an example of a perspective view of a cooling head
- FIG. 12 illustrates an example of a sectional view of the cooling head
- FIG. 13 illustrates an example of a sectional view of a cooling head.
- a plurality of nozzles protruding into a main flow channel are arranged in the flow channel direction of the main flow channel, and therefore the nozzles may cause a loss (pressure loss) in the flow of cooling water in the main flow channel.
- FIG. 1 illustrates an example of a cooling system.
- the cooling system 1 illustrated in FIG. 1 may be a system for cooling an electronic device 2 .
- the cooling system 1 includes a pump 4 , a radiator 6 , a cooling head 30 , and pipes 10 , 12 , 14 , and 16 .
- the cooling head 30 may include part of the pipe 10 , part or the whole of the pipes 12 and 14 , and/or part or the whole of the pipe 16 .
- the cooling head 30 may be provided for the electronic device 2 as illustrated in FIG. 1 .
- the electronic device 2 may be a heat generating device, element, component, or unit.
- the electronic device 2 may be, for example, a large-scale integration (LSI).
- An electronic apparatus 50 may include the cooling head 30 and the electronic device 2 .
- the electronic apparatus 50 may be a computer system such as an enhanced server or a supercomputer.
- the pipes 12 and 14 bifurcating from the pipe 10 are coupled to the suction side of the cooling head 30 .
- the pipe 16 is coupled to the discharge side of the cooling head 30 .
- the other end of each of the pipe 10 and the pipe 16 is coupled to the radiator 6 .
- the pipes 10 , 12 , 14 and 16 and the radiator 6 define a circulation flow channel.
- the pipe 10 is provided with the pump 4 .
- the pump 4 sucks refrigerant (for example, cooling water) cooled in the radiator 6 and discharges the refrigerant toward the cooling head 30 .
- the refrigerant discharged from the discharge side of the cooling head 30 (refrigerant that receives the heat of the electronic device 2 ) is supplied to the radiator 6 and is cooled (radiates heat).
- the configuration of the cooling system 1 illustrated in FIG. 1 is merely an example, and various modifications are possible.
- refrigerant discharged from one pump 4 is branched into two pipes 12 and 14 and supplied to the cooling head 30
- refrigerant may be supplied to the cooling head 30 through two independent pipes using two pumps.
- the pipe 12 may be provided with a valve.
- a transition tank or the like for creating a subcool state may not be provided.
- FIG. 2 illustrates an example of a relationship between a cooling head and a electronic device.
- arrows P 01 , P 02 , P 1 , P 2 , and P 4 schematically indicate the flow direction of refrigerant.
- the Z direction indicates the vertical direction, and the top of FIG. 2 may be the top in the vertical direction.
- FIG. 3 illustrates an example of a communication hole.
- communication holes 40 ′ that have nozzles and allow a first refrigerant flow channel and a second refrigerant flow channel to communicate with each other are illustrated.
- the cooling head 30 illustrated in FIG. 2 includes a first refrigerant flow channel 32 , a second refrigerant flow channel 34 , and communication holes 40 .
- the first refrigerant flow channel 32 is in contact with an object 3 to be cooled with a lower member 36 a therebetween.
- the object 3 to be cooled may be an electronic device 2 or an object that receives heat from an electronic device 2 .
- an object directly in contact with the lower member 36 a may be a heat spreader 3 a of an electronic device 2 .
- the first refrigerant flow channel 32 is in contact with the object 3 to be cooled from above, the first refrigerant flow channel 32 may be in contact with the object 3 to be cooled from below, or any other direction.
- the first refrigerant flow channel 32 may be in contact with the entire surface of the object 3 to be cooled as illustrated in FIG. 2 , or may be partially in contact with the object 3 to be cooled.
- the first refrigerant flow channel 32 defines a closed cross-section, for example, a pipe except for the positions of the communication holes 40 .
- the lower member 36 a that defines the lower side of the first refrigerant flow channel 32 , and an intermediate member 36 b that defines the upper side of the first refrigerant flow channel 32 are illustrated.
- the near side or far side (the near side or far side in a direction perpendicular to the X direction and Z direction) of the first refrigerant flow channel 32 may be defined, for example, by the side wall member 36 f or 36 e illustrated in FIG. 5 .
- Refrigerant is caused to flow through the first refrigerant flow channel 32 .
- the refrigerant from the pipe 14 is introduced into the first refrigerant flow channel 32 as indicated by arrow P 01 of FIG. 2 , flows through the first refrigerant flow channel 32 as indicated by arrows P 1 , exits the first refrigerant flow channel 32 and flows to the downstream side as indicated by arrow P 4 .
- the second refrigerant flow channel 34 is provided so as to be adjacent to the first refrigerant flow channel 32 .
- the second refrigerant flow channel 34 may be provided so as to be adjacent to the lower side of the first refrigerant flow channel 32 , or may be provided so as to be adjacent to the near side or far side (the near side or far side in a direction perpendicular to the X direction and Z direction) of the first refrigerant flow channel 32 .
- the second refrigerant flow channel 34 may be adjacent to the first refrigerant flow channel 32 in any direction.
- the second refrigerant flow channel 34 defines a pipe of a closed cross-section (except for the positions of the communication holes 40 ).
- the intermediate member 36 b that defines the lower side of the second refrigerant flow channel 34 , and a lid member 36 c that defines the upper side of the second refrigerant flow channel 34 are illustrated.
- the near side or far side (the near side or far side in a direction perpendicular to the X direction and Z direction) of the second refrigerant flow channel 34 may be defined, for example, by the side wall member 36 f or 36 e illustrated in FIG. 7 .
- the second refrigerant flow channel 34 is preferably blocked at the downstream end in the flow direction of refrigerant in the second refrigerant flow channel 34 .
- the second refrigerant flow channel 34 is blocked at the downstream end by a blocking member 36 d. Since the flow of refrigerant in the second refrigerant flow channel 34 is blocked by the blocking member 36 d, the inflow of refrigerant in the second refrigerant flow channel 34 into the first refrigerant flow channel 32 through the communication holes 40 (to be described later) is promoted.
- Refrigerant is caused to flow through the second refrigerant flow channel.
- the refrigerant from the pipe 12 is introduced into the second refrigerant flow channel 34 as indicated by arrow P 02 of FIG. 2 , flows through the second refrigerant flow channel 34 , flows into the first refrigerant flow channel 32 through the communication holes 40 as indicated by arrows P 2 , exits the first refrigerant flow channel 32 and flows to the downstream side as indicated by arrow P 4 .
- the refrigerant introduced into the second refrigerant flow channel 34 flows into the first refrigerant flow channel 32 through the communication holes 40 unless it flows back, and then, it exits the first refrigerant flow channel 32 and flows to the downstream side.
- refrigerant that does not flow into the first refrigerant flow channel 32 through the communication holes 40 may flow to the downstream side independently from the refrigerant in the first refrigerant flow channel 32 , or may be merged with the refrigerant in the first refrigerant flow channel 32 , may then exit the first refrigerant flow channel 32 , and may flow to the downstream side.
- the blocking member 36 d it may be advantageous in terms of the number of components and the cooling efficiency as compared to when the blocking member 36 d is not provided.
- the communication holes 40 are provided between both ends of the object 3 to be cooled of the first refrigerant flow channel 32 in the flow direction of refrigerant in the first refrigerant flow channel 32 .
- the three communication holes 40 are provided between both ends of the object 3 to be cooled of the first refrigerant flow channel 32 in the flow direction of refrigerant in the first refrigerant flow channel 32 .
- Both ends of the object 3 to be cooled may be both ends of the heat spreader 3 a or may be both ends of a heat generating source, for example, the electronic device 2 .
- the communication holes 40 do not have nozzles and allow the first refrigerant flow channel 32 and the second refrigerant flow channel 34 to communicate with each other.
- the communication holes 40 may be not in the form of nozzles protruding into the first refrigerant flow channel 32 , for example, in the form of the communication holes 40 ′ illustrated in FIG. 3 but simple holes formed in a flat surface or a curved surface.
- Communication holes 40 ′ having nozzles supply the refrigerant in the second refrigerant flow channel to positions close to the object 3 to be cooled. Therefore, in a cooling system using the boiling of liquid, for example, the system that removes bubbles generated by the heat from an object 3 to be cooled illustrated in FIG. 3 , communication holes 40 ′ having nozzles are provided.
- the communication holes 40 ′ having nozzles may cause a loss (pressure loss) in the flow in the first refrigerant flow channel 32 and may cause a decrease in cooling capacity.
- the refrigerant introduced from the pipe 14 into the first refrigerant flow channel 32 receives heat from the object 3 to be cooled (receives heat with the cooling of the object 3 to be cooled) as it flows downstream, and therefore the temperature (refrigerant temperature) increases. Therefore, in the refrigerant introduced from the pipe 14 into the first refrigerant flow channel 32 , the temperature on the upstream side of the object 3 to be cooled is lower than the temperature on the downstream side of the object 3 to be cooled, and non-uniform cooling may occur.
- the difference in temperature produced between the upstream side and the downstream side of flow is temperature variation in the temperature distribution on the surface of the electronic device.
- a state in which there is temperature variation is a state in which the effect of heat on the electronic device 2 varies, and is a state in which various distortions caused by heat, for example, the load is large.
- the load on the electronic device 2 may be preferably small.
- the communication holes 40 are provided between both ends of the object 3 to be cooled in the first refrigerant flow channel 32 in the flow direction of refrigerant in the first refrigerant flow channel 32 .
- non-uniform cooling may be remedied.
- refrigerant in the second refrigerant flow channel 34 for example, fresh refrigerant is introduced through the communication holes 40 , and therefore the increased temperature of refrigerant in the first refrigerant flow channel 32 decreases, and the cooling capacity may recover. Since the increase in the temperature of refrigerant on the downstream side of flow is reduced, the cooling capacity of refrigerant may be uniformized along the flow direction. Therefore, the load on the electronic device 2 may be reduced.
- the positions and number of the communication holes 40 , the flow rate of refrigerant introduced from the second refrigerant flow channel 34 through the communication holes 40 into the first refrigerant flow channel 32 , and the like may be set taking into account the heat generation distribution of the object 3 to be cooled, such that the temperature distribution of the object 3 to be cooled along the flow direction is a desired temperature distribution, for example, a uniform temperature distribution.
- FIG. 4 illustrates an example of cooling effect.
- the uniform heat generation means that the amount of heat generation is uniform in each region of the electronic device 2 .
- the hot spot means a part of the electronic device 2 in which the amount of heat generation is larger than in the other parts due to non-uniform heat generation, for example, a part in which the amount of heat generation is locally the maximum in a state where the electronic device 2 is alone.
- the hot spot H may exist, for example, on the downstream side in the flow direction of refrigerant of the electronic device 2 .
- each graph illustrating temperature distribution the horizontal axis indicates temperature measurement position (the origin side corresponds to the upstream side in the flow direction of refrigerant), and the vertical axis indicates temperature. For example, each graph illustrates the temperature distribution along the flow direction of refrigerant.
- the temperature distribution in the case of the uniform heat generation, the temperature distribution is such that, as illustrated in A of FIG. 4 , the temperature increases significantly in the center, and increases gradually toward the downstream side. The reason is that the temperature of refrigerant increases on the downstream side.
- the temperature distribution In the case of a hot spot, the temperature distribution is such that, as illustrated in A of FIG. 4 , the temperature increases gradually toward the downstream side, and increases steeply near the hot spot. The reason is that the temperature of refrigerant increases steeply owing to the hot spot on the downstream side.
- the electronic device 2 since refrigerant circulates in a direction, under the influence of temperature state of refrigerant, the electronic device 2 may not be cooled uniformly.
- the object 3 to be cooled is cooled substantially uniformly. Therefore, in the case of uniform heat generation, the temperature distribution is an arcuate temperature distribution as illustrated in B of FIG. 4 . Also in the case of a hot spot, the temperature distribution is an arcuate temperature distribution as illustrated in B of FIG. 4 , and the temperature increases only slightly near the hot spot. In both cases, the maximum temperature T 1 is low as compared to FIG. 3 .
- FIG. 5 illustrates an example of a top view of a first refrigerant flow channel.
- the first refrigerant flow channel 32 may be a single flow channel for one object 3 to be cooled, or may include a plurality of flow channels 32 a to 32 h for one object 3 to be cooled as illustrated in FIG. 5 .
- the plurality of flow channels 32 a to 32 h may extend parallel to each other.
- the plurality of flow channels 32 a to 32 h are divided from each other by partition walls 33 between the side wall members 36 e and 36 f in the Y direction.
- the intervals in the Y direction between the plurality of flow channels 32 a to 32 h are substantially the same, the intervals between some or all of the plurality of flow channels 32 a to 32 h may differ.
- the intervals in the Y direction between the plurality of flow channels 32 a to 32 h are substantially fixed along the X direction, they may change, for example, they may increase downstream.
- the partition walls 33 may be formed in only a part of the first refrigerant flow channel 32 .
- the partition walls 33 may be formed over the entire range of the electronic device 2 (or the object 3 to be cooled) in the flow direction, or may be formed only in a range under the communication holes 40 . Although, in FIG. 5 , all of the plurality of flow channels 32 a to 32 h pass over the same electronic device 2 (or object 3 to be cooled), only some of the plurality of flow channels may pass over the same electronic device 2 (or object 3 to be cooled).
- FIG. 6A and FIG. 6B each illustrate an example of a top view of a flow of refrigerant.
- FIG. 6A the flow of refrigerant near a communication hole 40 in the case where the first refrigerant flow channel 32 includes a single flow channel is illustrated.
- FIG. 6B the flow of refrigerant near a communication hole 40 in the case where the first refrigerant flow channel 32 includes a plurality of flow channels 32 a to 32 h is illustrated.
- the first refrigerant flow channel 32 includes a single flow channel
- the refrigerant in the second refrigerant flow channel 34 flows through the communication hole 40 into the first refrigerant flow channel 32
- the flow direction of the inflowing refrigerant may be disturbed, and vortexes and stagnation may tend to occur.
- the first refrigerant flow channel 32 includes a plurality of flow channels 32 a to 32 h
- the disturbance of the flow direction of the inflowing refrigerant or the occurrence of vortexes and stagnation due to disturbance may be reduced. Therefore, all of the refrigerant in the second refrigerant flow channel 34 flowing through the communication hole 40 into the first refrigerant flow channel 32 may be able to be caused to flow along the flow direction of the refrigerant in the first refrigerant flow channel 32 .
- FIG. 7 illustrates an example of a top view of a second refrigerant flow channel and a communication hole.
- the second refrigerant flow channel 34 may be disposed over the first refrigerant flow channel 32 such that they are completely superimposed on each other in top view.
- a two-tiered structure may be formed.
- the second refrigerant flow channel 34 is a single flow channel defined between the side wall members 36 e and 36 f in the Y direction, it may include a plurality of flow channels as with the first refrigerant flow channel 32 .
- the communication holes 40 may be formed, as illustrated in FIG. 7 , so as to be elongate in a direction (Y direction) across the flow direction (X direction) of the refrigerant in the first refrigerant flow channel 32 .
- each communication hole 40 may be shared by at least two of the plurality of flow channels 32 a to 32 h.
- the communication holes 40 may not communicate with the flow channels 32 a and 32 h at both ends in the Y direction.
- the communication holes 40 may be formed so as to communicate with all of the flow channels 32 a to 32 h of the first refrigerant flow channel 32 .
- FIG. 8 illustrates an example of a top view of a second refrigerant flow channel and a communication hole.
- the second refrigerant flow channel 34 may be disposed over the first refrigerant flow channel 32 such that they are completely superimposed on each other in top view. For example, a two-tiered structure may be formed.
- the plurality of flow channels 32 a to 32 h are provided with their respective communication holes 40 .
- the example illustrated in FIG. 8 may be combined with the example illustrated in FIG. 7 .
- a plurality of communication holes 40 provided for one electronic device 2 may include communication holes 40 each corresponding to one of the plurality of flow channels 32 a to 32 h, and communication holes 40 each shared by some of the plurality of flow channels 32 a to 32 h.
- FIG. 9 illustrates an example of an arrangement of communication hole.
- FIG. 9 an example of arrangement of communication holes in the case where there are hot spots on the electronic device 2 is illustrated.
- communication holes 40 may be provided so as to correspond to the positions of the hot spots in the X direction, or may be provided on the upstream side of the positions of the hot spots.
- Refrigerant having high cooling capacity for example, the refrigerant in the second refrigerant flow channel 34 is introduced near the hot spots of the electronic device 2 . Therefore, the hot spots of the electronic device 2 may be cooled intensively and efficiently.
- the communication holes 40 may be provided just above the hot spot H 1 so as to correspond to the position of the hot spot H 1 .
- the communication holes 40 may be provided on the upstream side of the position of the hot spot H 1 .
- the positions of two hot spots in the X direction are indicated by signs H 1 and H 2 .
- the communication hole 40 on the upstream side is formed just above the hot spot H 1 so as to correspond to the position of the hot spot H 1
- the communication hole 40 on the downstream side is formed on the upstream side of (just short of) the position of the hot spot H 2 .
- FIG. 10 illustrates an example of an exploded perspective view of a cooling head.
- the cooling head 30 A illustrated in FIG. 10 may differ from the parts of the cooling head 30 illustrated in FIG. 5 and FIG. 7 , for example, in the number of the partition walls 33 , and the length of the communication holes 40 .
- the configuration illustrated in FIG. 10 may be substantially the same as or similar to the configuration illustrated in FIG. 5 or FIG. 7 .
- the cooling head 30 A includes a first flow channel member 100 , a second flow channel member 200 , and a lid member 36 c .
- the first flow channel member 100 , the second flow channel member 200 , and the lid member 36 c may be formed of a highly heat-conductive material, for example, copper.
- the first flow channel member 100 , the second flow channel member 200 , and the lid member 36 c may be integrated by welding or the like.
- a first refrigerant flow channel 32 is formed in the first flow channel member 100 .
- the first flow channel member 100 includes a joint portion 102 coupled to the pipe 14 (see FIG. 1 ) from the pump 4 , and a joint portion 104 coupled to the pipe 16 (see FIG. 1 ) leading to the radiator 6 .
- refrigerant introduced through the joint portion 102 flows into the first refrigerant flow channel 32 through an upstream flow channel 106 whose width increases toward the downstream side.
- refrigerant that exits the first refrigerant flow channel 32 and flows to the downstream side flows to the joint portion 104 through a downstream flow channel 108 whose width decreases toward the downstream side.
- the second flow channel member 200 is stacked on the first flow channel member 100 .
- a second refrigerant flow channel 34 and communication holes 40 are formed in the second flow channel member 200 .
- the second flow channel member 200 includes a joint portion 202 coupled to the pipe 12 (see FIG. 1 ) from the pump 4 .
- the downstream side of the second flow channel member 200 is blocked by a blocking member 36 d, and therefore there may be no joint portion leading to the radiator 6 .
- refrigerant introduced through the joint portion 202 flows into the second refrigerant flow channel 34 through an upstream flow channel 206 whose width increases toward the downstream side.
- a downstream flow channel 208 corresponding to the downstream flow channel 108 is formed in the second flow channel member 200 .
- the downstream flow channel 208 may not be provided.
- the blocking member 36 d is moved to the upstream side.
- the intermediate member 36 b may extend over the downstream flow channel 108 of the first flow channel member 100 and may function as a lid.
- the lid member 36 c may have a shape corresponding to the peripheral wall portion of the second flow channel member 200 .
- the lid member 36 c is placed on the second flow channel member 200 and defines the upper side of the second refrigerant flow channel 34 .
- FIG. 11 illustrates an example of a perspective view of a cooling head.
- FIG. 12 illustrates an example of a sectional view of a cooling head.
- a sectional view of the cooling head 30 B illustrated in FIG. 11 taken along the longitudinal center line of the second flow channel member 220 is illustrated.
- the cooling head 30 B illustrated in FIG. 11 and FIG. 12 differs from the cooling head 30 A illustrated in FIG. 10 in that a second refrigerant flow channel 34 is formed in a pipe-like second flow channel member 220 .
- a second refrigerant flow channel 34 is formed in a pipe-like second flow channel member 220 .
- a pipe-like second flow channel member 220 is provided in the cooling head 30 B illustrated in FIG. 11 and FIG. 12 .
- the configuration of the first flow channel member 100 B of the cooling head 30 B may be substantially the same as or similar to the configuration of the first flow channel member 100 .
- the second flow channel member 220 includes a pipe portion 221 that branches from the joint portion 102 and extends upward, a pipe portion 222 that bends from the pipe portion 221 and extends along the flow direction of refrigerant in the first refrigerant flow channel 32 , and two pipe portions 223 and 224 that extend downward from the pipe portion 222 .
- the pipe portion 223 has such a form that its width increases toward its lower end as illustrated in FIG. 11 .
- the end in the flow direction of the pipe portion 222 is closed, and refrigerant introduced into the second flow channel member 220 flows from the pipe portions 223 and 224 through communication holes 40 into the first refrigerant flow channel 32 unless it flows back.
- the communication holes 40 are provided between both ends of the object 3 to be cooled in the first refrigerant flow channel 32 in the flow direction of refrigerant in the first refrigerant flow channel 32 .
- the cooling head 30 B illustrated in FIG. 11 and FIG. 12 may also provide the same advantageous effect as that of the cooling head 30 A illustrated in FIG. 10 .
- the first flow channel member 100 and the second flow channel member 220 may not be stacked vertically like the first flow channel member 100 and the second flow channel member 200 of the cooling head 30 A illustrated in FIG. 10 .
- the pipe portions 223 and 224 extend vertically, and therefore when flowing through the pipe portions 223 and 224 , refrigerant obtains a flow velocity in the direction of gravitational force owing to the gravitational force. Therefore, the flowing of refrigerant in the second refrigerant flow channel 34 through the communication holes 40 into the first refrigerant flow channel 32 is promoted.
- first refrigerant flow channel 32 and the second refrigerant flow channel 34 have a positional relationship (angular relationship) such that refrigerant flows in the same direction
- first refrigerant flow channel 32 and the second refrigerant flow channel 34 may have a positional relationship (angular relationship) such that refrigerant flows in different directions (directions intersecting each other or opposite each other).
- the second refrigerant flow channel 34 may extend in a direction rotated by an arbitrary angle about the Z axis.
- the second refrigerant flow channel 34 may be mirror-reversed (in this case, refrigerant flows from right to left of FIG. 2 ), or may be rotated 90 degrees about the Z axis (in this case, refrigerant flows in a direction perpendicular to the X axis and the Z axis).
- FIG. 13 illustrates an example of a sectional view of a cooling head.
- an upper member 360 b of a first refrigerant flow channel 32 and a lower member 362 b of a second refrigerant flow channel 34 are vertically offset from each other, and the upper member 360 b and the lower member 362 b may be coupled by pipe members 364 a extending vertically.
- the lower ends of the pipe members 364 a may be open without having nozzles in communication holes 40 .
- cooling head 30 , 30 A, 30 B, or 30 C is provided for one electronic device 2 , it may be shared by two or more electronic devices 2 .
- the lower member 36 a may be a heat spreader 3 a.
- the refrigerant may be cooling water or another fluid such as air.
Abstract
A cooling head includes: a first refrigerant flow channel, provided so as to be in contact with an object to be cooled, configured to flow refrigerant; a second refrigerant flow channel configured to flow the refrigerant; and at least one communication hole, provided between both ends of the object to be cooled in the first refrigerant flow channel in a first flow direction of refrigerant in the first refrigerant flow channel, configured to allow the first refrigerant flow channel and the second refrigerant flow channel to communicate with each other.
Description
- This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2013-002853, filed on Jan. 10, 2013, the entire contents of which are incorporated herein by reference.
- Embodiments discussed herein are related to a cooling head and an electronic apparatus.
- In the boil cooling method, a main flow channel and a sub-flow channel for a cooling liquid are formed in this order from the side of the cooling surface. A plurality of nozzles that penetrate a partition wall separating the sub-flow channel and the main flow channel and that protrude into the main flow channel are arranged in the flow channel direction of the main flow channel, and tip end parts of the individual nozzles are caused to be in the vicinity of or in contact with the cooling surface. The cooling liquid is caused to circulate to the main flow channel and the sub-flow channel, the cooling surface is cooled with boiling of the cooling liquid flowing through the main flow channel, and the cooling liquid on the sub-flow channel side is supplied from the sub-flow channel side through each of the nozzles so as to exude in the vicinity of the cooling surface.
- A related art is disclosed in Japanese Laid-open Patent Publication No. 2007-150216.
- According to one aspect of the embodiments, a cooling head includes: a first refrigerant flow channel, provided so as to be in contact with an object to be cooled, configured to flow refrigerant; a second refrigerant flow channel configured to flow the refrigerant; and at least one communication hole, provided between both ends of the object to be cooled in the first refrigerant flow channel in a first flow direction of refrigerant in the first refrigerant flow channel, configured to allow the first refrigerant flow channel and the second refrigerant flow channel to communicate with each other.
- The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims.
- It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.
-
FIG. 1 illustrates an example of a cooling system; -
FIG. 2 illustrates an example of a relationship between a cooling head and an electronic device; -
FIG. 3 illustrates an example of a communication hole; -
FIG. 4 illustrates an example of cooling effect; -
FIG. 5 illustrates an example of a top view of a first refrigerant flow channel; -
FIG. 6A andFIG. 6B each illustrate an example of a top view of the flow of refrigerant; -
FIG. 7 illustrates an example of a top view of a second refrigerant flow channel and a communication hole; -
FIG. 8 illustrates an example of a top view of a second refrigerant flow channel and a communication hole; -
FIG. 9 illustrates an example of arrangement of a communication hole; -
FIG. 10 illustrates an example of an exploded perspective view of a cooling head; -
FIG. 11 illustrates an example of a perspective view of a cooling head; -
FIG. 12 illustrates an example of a sectional view of the cooling head; and -
FIG. 13 illustrates an example of a sectional view of a cooling head. - In the boil cooling method, a plurality of nozzles protruding into a main flow channel are arranged in the flow channel direction of the main flow channel, and therefore the nozzles may cause a loss (pressure loss) in the flow of cooling water in the main flow channel.
-
FIG. 1 illustrates an example of a cooling system. Thecooling system 1 illustrated inFIG. 1 may be a system for cooling anelectronic device 2. Thecooling system 1 includes apump 4, a radiator 6, acooling head 30, andpipes cooling head 30 may include part of thepipe 10, part or the whole of thepipes pipe 16. - The
cooling head 30 may be provided for theelectronic device 2 as illustrated inFIG. 1 . Theelectronic device 2 may be a heat generating device, element, component, or unit. Theelectronic device 2 may be, for example, a large-scale integration (LSI). Anelectronic apparatus 50 may include thecooling head 30 and theelectronic device 2. Theelectronic apparatus 50 may be a computer system such as an enhanced server or a supercomputer. - The
pipes pipe 10 are coupled to the suction side of thecooling head 30. Thepipe 16 is coupled to the discharge side of thecooling head 30. The other end of each of thepipe 10 and thepipe 16 is coupled to the radiator 6. Thus, thepipes pipe 10 is provided with thepump 4. Thepump 4 sucks refrigerant (for example, cooling water) cooled in the radiator 6 and discharges the refrigerant toward thecooling head 30. The refrigerant discharged from the discharge side of the cooling head 30 (refrigerant that receives the heat of the electronic device 2) is supplied to the radiator 6 and is cooled (radiates heat). - The configuration of the
cooling system 1 illustrated inFIG. 1 is merely an example, and various modifications are possible. For example, although, inFIG. 1 , refrigerant discharged from onepump 4 is branched into twopipes cooling head 30, refrigerant may be supplied to thecooling head 30 through two independent pipes using two pumps. For example, thepipe 12 may be provided with a valve. In thecooling system 1 illustrated inFIG. 1 , a transition tank or the like for creating a subcool state may not be provided. -
FIG. 2 illustrates an example of a relationship between a cooling head and a electronic device. InFIG. 2 , arrows P01, P02, P1, P2, and P4 schematically indicate the flow direction of refrigerant. The Z direction indicates the vertical direction, and the top ofFIG. 2 may be the top in the vertical direction.FIG. 3 illustrates an example of a communication hole. InFIG. 3 ,communication holes 40′ that have nozzles and allow a first refrigerant flow channel and a second refrigerant flow channel to communicate with each other are illustrated. - The
cooling head 30 illustrated inFIG. 2 includes a firstrefrigerant flow channel 32, a secondrefrigerant flow channel 34, andcommunication holes 40. - The first
refrigerant flow channel 32 is in contact with anobject 3 to be cooled with alower member 36 a therebetween. Theobject 3 to be cooled may be anelectronic device 2 or an object that receives heat from anelectronic device 2. For example, an object directly in contact with thelower member 36 a may be aheat spreader 3 a of anelectronic device 2. Although, inFIG. 2 , the firstrefrigerant flow channel 32 is in contact with theobject 3 to be cooled from above, the firstrefrigerant flow channel 32 may be in contact with theobject 3 to be cooled from below, or any other direction. The firstrefrigerant flow channel 32 may be in contact with the entire surface of theobject 3 to be cooled as illustrated inFIG. 2 , or may be partially in contact with theobject 3 to be cooled. - The first
refrigerant flow channel 32 defines a closed cross-section, for example, a pipe except for the positions of thecommunication holes 40. InFIG. 2 , thelower member 36 a that defines the lower side of the firstrefrigerant flow channel 32, and anintermediate member 36 b that defines the upper side of the firstrefrigerant flow channel 32 are illustrated. The near side or far side (the near side or far side in a direction perpendicular to the X direction and Z direction) of the firstrefrigerant flow channel 32 may be defined, for example, by theside wall member FIG. 5 . - Refrigerant is caused to flow through the first
refrigerant flow channel 32. The refrigerant from thepipe 14 is introduced into the firstrefrigerant flow channel 32 as indicated by arrow P01 ofFIG. 2 , flows through the firstrefrigerant flow channel 32 as indicated by arrows P1, exits the firstrefrigerant flow channel 32 and flows to the downstream side as indicated by arrow P4. - The second
refrigerant flow channel 34 is provided so as to be adjacent to the firstrefrigerant flow channel 32. Although, inFIG. 2 , the secondrefrigerant flow channel 34 is adjacent to the upper side of the firstrefrigerant flow channel 32, the secondrefrigerant flow channel 34 may be provided so as to be adjacent to the lower side of the firstrefrigerant flow channel 32, or may be provided so as to be adjacent to the near side or far side (the near side or far side in a direction perpendicular to the X direction and Z direction) of the firstrefrigerant flow channel 32. The secondrefrigerant flow channel 34 may be adjacent to the firstrefrigerant flow channel 32 in any direction. - The second
refrigerant flow channel 34 defines a pipe of a closed cross-section (except for the positions of the communication holes 40). InFIG. 2 , theintermediate member 36 b that defines the lower side of the secondrefrigerant flow channel 34, and alid member 36 c that defines the upper side of the secondrefrigerant flow channel 34 are illustrated. The near side or far side (the near side or far side in a direction perpendicular to the X direction and Z direction) of the secondrefrigerant flow channel 34 may be defined, for example, by theside wall member FIG. 7 . - The second
refrigerant flow channel 34 is preferably blocked at the downstream end in the flow direction of refrigerant in the secondrefrigerant flow channel 34. InFIG. 2 , the secondrefrigerant flow channel 34 is blocked at the downstream end by a blockingmember 36 d. Since the flow of refrigerant in the secondrefrigerant flow channel 34 is blocked by the blockingmember 36 d, the inflow of refrigerant in the secondrefrigerant flow channel 34 into the firstrefrigerant flow channel 32 through the communication holes 40 (to be described later) is promoted. - Refrigerant is caused to flow through the second refrigerant flow channel. The refrigerant from the
pipe 12 is introduced into the secondrefrigerant flow channel 34 as indicated by arrow P02 ofFIG. 2 , flows through the secondrefrigerant flow channel 34, flows into the firstrefrigerant flow channel 32 through the communication holes 40 as indicated by arrows P2, exits the firstrefrigerant flow channel 32 and flows to the downstream side as indicated by arrow P4. InFIG. 2 , since the blockingmember 36 d is provided, the refrigerant introduced into the secondrefrigerant flow channel 34 flows into the firstrefrigerant flow channel 32 through the communication holes 40 unless it flows back, and then, it exits the firstrefrigerant flow channel 32 and flows to the downstream side. When the blockingmember 36 d is not provided, refrigerant that does not flow into the firstrefrigerant flow channel 32 through the communication holes 40, for example, refrigerant that exits from the downstream opening of the second refrigerant flow channel, may flow to the downstream side independently from the refrigerant in the firstrefrigerant flow channel 32, or may be merged with the refrigerant in the firstrefrigerant flow channel 32, may then exit the firstrefrigerant flow channel 32, and may flow to the downstream side. When the blockingmember 36 d is provided, it may be advantageous in terms of the number of components and the cooling efficiency as compared to when the blockingmember 36 d is not provided. - The communication holes 40 are provided between both ends of the
object 3 to be cooled of the firstrefrigerant flow channel 32 in the flow direction of refrigerant in the firstrefrigerant flow channel 32. InFIG. 2 , the threecommunication holes 40 are provided between both ends of theobject 3 to be cooled of the firstrefrigerant flow channel 32 in the flow direction of refrigerant in the firstrefrigerant flow channel 32. Both ends of theobject 3 to be cooled may be both ends of theheat spreader 3 a or may be both ends of a heat generating source, for example, theelectronic device 2. - The communication holes 40 do not have nozzles and allow the first
refrigerant flow channel 32 and the secondrefrigerant flow channel 34 to communicate with each other. For example, the communication holes 40 may be not in the form of nozzles protruding into the firstrefrigerant flow channel 32, for example, in the form of the communication holes 40′ illustrated inFIG. 3 but simple holes formed in a flat surface or a curved surface. Communication holes 40′ having nozzles supply the refrigerant in the second refrigerant flow channel to positions close to theobject 3 to be cooled. Therefore, in a cooling system using the boiling of liquid, for example, the system that removes bubbles generated by the heat from anobject 3 to be cooled illustrated inFIG. 3 , communication holes 40′ having nozzles are provided. The communication holes 40′ having nozzles may cause a loss (pressure loss) in the flow in the firstrefrigerant flow channel 32 and may cause a decrease in cooling capacity. - When focusing on the refrigerant introduced from the
pipe 14 into the firstrefrigerant flow channel 32, the refrigerant introduced from thepipe 14 into the firstrefrigerant flow channel 32 receives heat from theobject 3 to be cooled (receives heat with the cooling of theobject 3 to be cooled) as it flows downstream, and therefore the temperature (refrigerant temperature) increases. Therefore, in the refrigerant introduced from thepipe 14 into the firstrefrigerant flow channel 32, the temperature on the upstream side of theobject 3 to be cooled is lower than the temperature on the downstream side of theobject 3 to be cooled, and non-uniform cooling may occur. - The difference in temperature produced between the upstream side and the downstream side of flow is temperature variation in the temperature distribution on the surface of the electronic device. A state in which there is temperature variation is a state in which the effect of heat on the
electronic device 2 varies, and is a state in which various distortions caused by heat, for example, the load is large. In order to stably operate theelectronic device 2 or a system including theelectronic device 2, for example, theelectronic apparatus 50 over a long period of time, the load on theelectronic device 2 may be preferably small. - For example, since the communication holes 40 are provided between both ends of the
object 3 to be cooled in the firstrefrigerant flow channel 32 in the flow direction of refrigerant in the firstrefrigerant flow channel 32, non-uniform cooling may be remedied. For example, at a position where the temperature of refrigerant introduced into the firstrefrigerant flow channel 32 increases, refrigerant in the secondrefrigerant flow channel 34, for example, fresh refrigerant is introduced through the communication holes 40, and therefore the increased temperature of refrigerant in the firstrefrigerant flow channel 32 decreases, and the cooling capacity may recover. Since the increase in the temperature of refrigerant on the downstream side of flow is reduced, the cooling capacity of refrigerant may be uniformized along the flow direction. Therefore, the load on theelectronic device 2 may be reduced. - The positions and number of the communication holes 40, the flow rate of refrigerant introduced from the second
refrigerant flow channel 34 through the communication holes 40 into the firstrefrigerant flow channel 32, and the like may be set taking into account the heat generation distribution of theobject 3 to be cooled, such that the temperature distribution of theobject 3 to be cooled along the flow direction is a desired temperature distribution, for example, a uniform temperature distribution. -
FIG. 4 illustrates an example of cooling effect. InFIG. 4 , in each of the case of uniform heat generation and the case in which there is a hot spot, two types of temperature distribution are illustrated. The uniform heat generation means that the amount of heat generation is uniform in each region of theelectronic device 2. The hot spot means a part of theelectronic device 2 in which the amount of heat generation is larger than in the other parts due to non-uniform heat generation, for example, a part in which the amount of heat generation is locally the maximum in a state where theelectronic device 2 is alone. InFIG. 4 , the hot spot H may exist, for example, on the downstream side in the flow direction of refrigerant of theelectronic device 2. The temperature distribution illustrated inFIG. 4 is temperature distribution after cooling, and may correspond to the temperature distribution of the electronic device 2 (the temperature distribution on the surface of the electronic device). In each graph illustrating temperature distribution, the horizontal axis indicates temperature measurement position (the origin side corresponds to the upstream side in the flow direction of refrigerant), and the vertical axis indicates temperature. For example, each graph illustrates the temperature distribution along the flow direction of refrigerant. - In
FIG. 3 , in the case of the uniform heat generation, the temperature distribution is such that, as illustrated in A ofFIG. 4 , the temperature increases significantly in the center, and increases gradually toward the downstream side. The reason is that the temperature of refrigerant increases on the downstream side. In the case of a hot spot, the temperature distribution is such that, as illustrated in A ofFIG. 4 , the temperature increases gradually toward the downstream side, and increases steeply near the hot spot. The reason is that the temperature of refrigerant increases steeply owing to the hot spot on the downstream side. As just described, since refrigerant circulates in a direction, under the influence of temperature state of refrigerant, theelectronic device 2 may not be cooled uniformly. - In
FIG. 2 , theobject 3 to be cooled is cooled substantially uniformly. Therefore, in the case of uniform heat generation, the temperature distribution is an arcuate temperature distribution as illustrated in B ofFIG. 4 . Also in the case of a hot spot, the temperature distribution is an arcuate temperature distribution as illustrated in B ofFIG. 4 , and the temperature increases only slightly near the hot spot. In both cases, the maximum temperature T1 is low as compared toFIG. 3 . -
FIG. 5 illustrates an example of a top view of a first refrigerant flow channel. The firstrefrigerant flow channel 32 may be a single flow channel for oneobject 3 to be cooled, or may include a plurality offlow channels 32 a to 32 h for oneobject 3 to be cooled as illustrated inFIG. 5 . The plurality offlow channels 32 a to 32 h may extend parallel to each other. The plurality offlow channels 32 a to 32 h are divided from each other bypartition walls 33 between theside wall members FIG. 5 , the intervals in the Y direction between the plurality offlow channels 32 a to 32 h are substantially the same, the intervals between some or all of the plurality offlow channels 32 a to 32 h may differ. Although the intervals in the Y direction between the plurality offlow channels 32 a to 32 h are substantially fixed along the X direction, they may change, for example, they may increase downstream. Although, inFIG. 5 , the plurality offlow channels 32 a to 32 h exist from end to end in the X direction (flow direction), thepartition walls 33 may be formed in only a part of the firstrefrigerant flow channel 32. Thepartition walls 33 may be formed over the entire range of the electronic device 2 (or theobject 3 to be cooled) in the flow direction, or may be formed only in a range under the communication holes 40. Although, inFIG. 5 , all of the plurality offlow channels 32 a to 32 h pass over the same electronic device 2 (orobject 3 to be cooled), only some of the plurality of flow channels may pass over the same electronic device 2 (orobject 3 to be cooled). -
FIG. 6A andFIG. 6B each illustrate an example of a top view of a flow of refrigerant. InFIG. 6A , the flow of refrigerant near acommunication hole 40 in the case where the firstrefrigerant flow channel 32 includes a single flow channel is illustrated. InFIG. 6B , the flow of refrigerant near acommunication hole 40 in the case where the firstrefrigerant flow channel 32 includes a plurality offlow channels 32 a to 32 h is illustrated. - As indicated by dashed arrows of
FIG. 6A , in the case where the firstrefrigerant flow channel 32 includes a single flow channel, when the refrigerant in the secondrefrigerant flow channel 34 flows through thecommunication hole 40 into the firstrefrigerant flow channel 32, the flow direction of the inflowing refrigerant may be disturbed, and vortexes and stagnation may tend to occur. - As indicated by dashed arrows of
FIG. 6B , in the case where the firstrefrigerant flow channel 32 includes a plurality offlow channels 32 a to 32 h, when the refrigerant in the secondrefrigerant flow channel 34 flows through thecommunication hole 40 into the firstrefrigerant flow channel 32, the disturbance of the flow direction of the inflowing refrigerant or the occurrence of vortexes and stagnation due to disturbance may be reduced. Therefore, all of the refrigerant in the secondrefrigerant flow channel 34 flowing through thecommunication hole 40 into the firstrefrigerant flow channel 32 may be able to be caused to flow along the flow direction of the refrigerant in the firstrefrigerant flow channel 32. -
FIG. 7 illustrates an example of a top view of a second refrigerant flow channel and a communication hole. For example, when the configuration illustrated inFIG. 7 and the configuration of the firstrefrigerant flow channel 32 including a plurality offlow channels 32 a to 32 h illustrated inFIG. 5 are combined, the secondrefrigerant flow channel 34 may be disposed over the firstrefrigerant flow channel 32 such that they are completely superimposed on each other in top view. For example, a two-tiered structure may be formed. - Although, in
FIG. 7 , the secondrefrigerant flow channel 34 is a single flow channel defined between theside wall members refrigerant flow channel 32. The communication holes 40 may be formed, as illustrated inFIG. 7 , so as to be elongate in a direction (Y direction) across the flow direction (X direction) of the refrigerant in the firstrefrigerant flow channel 32. When combined with the configuration of the firstrefrigerant flow channel 32 including a plurality offlow channels 32 a to 32 h illustrated inFIG. 5 , eachcommunication hole 40 may be shared by at least two of the plurality offlow channels 32 a to 32 h. InFIG. 7 , in the case of the uniform heat generation, the necessity of cooling the end portions of theobject 3 to be cooled may be not so high. Therefore, the communication holes 40 may not communicate with theflow channels flow channels 32 a to 32 h of the firstrefrigerant flow channel 32. -
FIG. 8 illustrates an example of a top view of a second refrigerant flow channel and a communication hole. When the configuration illustrated inFIG. 8 and the configuration of the firstrefrigerant flow channel 32 including a plurality offlow channels 32 a to 32 h illustrated inFIG. 5 are combined, the secondrefrigerant flow channel 34 may be disposed over the firstrefrigerant flow channel 32 such that they are completely superimposed on each other in top view. For example, a two-tiered structure may be formed. - In
FIG. 8 , the plurality offlow channels 32 a to 32 h are provided with their respective communication holes 40. The example illustrated inFIG. 8 may be combined with the example illustrated inFIG. 7 . For example, a plurality of communication holes 40 provided for oneelectronic device 2 may include communication holes 40 each corresponding to one of the plurality offlow channels 32 a to 32 h, and communication holes 40 each shared by some of the plurality offlow channels 32 a to 32 h. -
FIG. 9 illustrates an example of an arrangement of communication hole. InFIG. 9 , an example of arrangement of communication holes in the case where there are hot spots on theelectronic device 2 is illustrated. - In the case where there are hot spots on the
electronic device 2, communication holes 40 may be provided so as to correspond to the positions of the hot spots in the X direction, or may be provided on the upstream side of the positions of the hot spots. Refrigerant having high cooling capacity, for example, the refrigerant in the secondrefrigerant flow channel 34 is introduced near the hot spots of theelectronic device 2. Therefore, the hot spots of theelectronic device 2 may be cooled intensively and efficiently. When sufficient pressure for the inflow of the refrigerant in the secondrefrigerant flow channel 34 through the communication holes 40 into the firstrefrigerant flow channel 32 is obtained, the communication holes 40 may be provided just above the hot spot H1 so as to correspond to the position of the hot spot H1. When sufficient pressure for the inflow of the refrigerant in the secondrefrigerant flow channel 34 through the communication holes 40 into the firstrefrigerant flow channel 32 is not obtained, the communication holes 40 may be provided on the upstream side of the position of the hot spot H1. InFIG. 9 , the positions of two hot spots in the X direction are indicated by signs H1 and H2. Thecommunication hole 40 on the upstream side is formed just above the hot spot H1 so as to correspond to the position of the hot spot H1, and thecommunication hole 40 on the downstream side is formed on the upstream side of (just short of) the position of the hot spot H2. -
FIG. 10 illustrates an example of an exploded perspective view of a cooling head. The coolinghead 30A illustrated inFIG. 10 may differ from the parts of the coolinghead 30 illustrated inFIG. 5 andFIG. 7 , for example, in the number of thepartition walls 33, and the length of the communication holes 40. In other respects, the configuration illustrated inFIG. 10 may be substantially the same as or similar to the configuration illustrated inFIG. 5 orFIG. 7 . - The cooling
head 30A includes a firstflow channel member 100, a secondflow channel member 200, and alid member 36 c. The firstflow channel member 100, the secondflow channel member 200, and thelid member 36 c may be formed of a highly heat-conductive material, for example, copper. The firstflow channel member 100, the secondflow channel member 200, and thelid member 36 c may be integrated by welding or the like. - In the first
flow channel member 100, a firstrefrigerant flow channel 32 is formed. InFIG. 10 , as with the example illustrated inFIG. 5 , a plurality ofpartition walls 33 are provided in the firstflow channel member 100. Therefore, the firstrefrigerant flow channel 32 has a plurality of flow channels. The firstflow channel member 100 includes ajoint portion 102 coupled to the pipe 14 (seeFIG. 1 ) from thepump 4, and ajoint portion 104 coupled to the pipe 16 (seeFIG. 1 ) leading to the radiator 6. InFIG. 10 , refrigerant introduced through thejoint portion 102 flows into the firstrefrigerant flow channel 32 through anupstream flow channel 106 whose width increases toward the downstream side. InFIG. 10 , refrigerant that exits the firstrefrigerant flow channel 32 and flows to the downstream side flows to thejoint portion 104 through adownstream flow channel 108 whose width decreases toward the downstream side. - The second
flow channel member 200 is stacked on the firstflow channel member 100. In the secondflow channel member 200, a secondrefrigerant flow channel 34 and communication holes 40 are formed. The secondflow channel member 200 includes ajoint portion 202 coupled to the pipe 12 (seeFIG. 1 ) from thepump 4. The downstream side of the secondflow channel member 200 is blocked by a blockingmember 36 d, and therefore there may be no joint portion leading to the radiator 6. InFIG. 10 , refrigerant introduced through thejoint portion 202 flows into the secondrefrigerant flow channel 34 through anupstream flow channel 206 whose width increases toward the downstream side. InFIG. 10 , adownstream flow channel 208 corresponding to thedownstream flow channel 108 is formed in the secondflow channel member 200. However, thedownstream flow channel 208 may not be provided. In this case, the blockingmember 36 d is moved to the upstream side. Theintermediate member 36 b may extend over thedownstream flow channel 108 of the firstflow channel member 100 and may function as a lid. - The
lid member 36 c may have a shape corresponding to the peripheral wall portion of the secondflow channel member 200. Thelid member 36 c is placed on the secondflow channel member 200 and defines the upper side of the secondrefrigerant flow channel 34. -
FIG. 11 illustrates an example of a perspective view of a cooling head.FIG. 12 illustrates an example of a sectional view of a cooling head. InFIG. 12 , a sectional view of the coolinghead 30B illustrated inFIG. 11 taken along the longitudinal center line of the secondflow channel member 220 is illustrated. - The cooling
head 30B illustrated inFIG. 11 andFIG. 12 differs from the coolinghead 30A illustrated inFIG. 10 in that a secondrefrigerant flow channel 34 is formed in a pipe-like secondflow channel member 220. For example, in thecooling head 30B illustrated inFIG. 11 andFIG. 12 , instead of the secondflow channel member 200 illustrated inFIG. 10 , a pipe-like secondflow channel member 220 is provided. In other respects, the configuration of the firstflow channel member 100B of the coolinghead 30B may be substantially the same as or similar to the configuration of the firstflow channel member 100. - The second
flow channel member 220 includes apipe portion 221 that branches from thejoint portion 102 and extends upward, apipe portion 222 that bends from thepipe portion 221 and extends along the flow direction of refrigerant in the firstrefrigerant flow channel 32, and twopipe portions pipe portion 222. Thepipe portion 223 has such a form that its width increases toward its lower end as illustrated inFIG. 11 . The end in the flow direction of thepipe portion 222 is closed, and refrigerant introduced into the secondflow channel member 220 flows from thepipe portions refrigerant flow channel 32 unless it flows back. The communication holes 40 are provided between both ends of theobject 3 to be cooled in the firstrefrigerant flow channel 32 in the flow direction of refrigerant in the firstrefrigerant flow channel 32. - The cooling
head 30B illustrated inFIG. 11 andFIG. 12 may also provide the same advantageous effect as that of the coolinghead 30A illustrated inFIG. 10 . The firstflow channel member 100 and the secondflow channel member 220 may not be stacked vertically like the firstflow channel member 100 and the secondflow channel member 200 of the coolinghead 30A illustrated inFIG. 10 . In thecooling head 30B illustrated inFIG. 11 andFIG. 12 , thepipe portions pipe portions refrigerant flow channel 34 through the communication holes 40 into the firstrefrigerant flow channel 32 is promoted. - For example, although the first
refrigerant flow channel 32 and the secondrefrigerant flow channel 34 have a positional relationship (angular relationship) such that refrigerant flows in the same direction, the firstrefrigerant flow channel 32 and the secondrefrigerant flow channel 34 may have a positional relationship (angular relationship) such that refrigerant flows in different directions (directions intersecting each other or opposite each other). For example, inFIG. 2 , the secondrefrigerant flow channel 34 may extend in a direction rotated by an arbitrary angle about the Z axis. For example, the secondrefrigerant flow channel 34 may be mirror-reversed (in this case, refrigerant flows from right to left ofFIG. 2 ), or may be rotated 90 degrees about the Z axis (in this case, refrigerant flows in a direction perpendicular to the X axis and the Z axis). - Although, in
FIG. 2 , the firstrefrigerant flow channel 32 and the secondrefrigerant flow channel 34 are vertically adjacent to each other with theintermediate member 36 b therebetween, the firstrefrigerant flow channel 32 and the secondrefrigerant flow channel 34 may be vertically separated from each other.FIG. 13 illustrates an example of a sectional view of a cooling head. For example, in thecooling head 30C illustrated inFIG. 13 , an upper member 360 b of a firstrefrigerant flow channel 32 and alower member 362 b of a secondrefrigerant flow channel 34 are vertically offset from each other, and the upper member 360 b and thelower member 362 b may be coupled bypipe members 364 a extending vertically. The lower ends of thepipe members 364 a may be open without having nozzles in communication holes 40. - Although the cooling
head electronic device 2, it may be shared by two or moreelectronic devices 2. - In
FIG. 2 , thelower member 36 a may be aheat spreader 3 a. - The refrigerant may be cooling water or another fluid such as air.
- All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiments of the present invention have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.
Claims (20)
1. A cooling head comprising:
a first refrigerant flow channel, provided so as to be in contact with an object to be cooled, configured to flow refrigerant;
a second refrigerant flow channel configured to flow the refrigerant; and
at least one communication hole, provided between both ends of the object to be cooled in the first refrigerant flow channel in a first flow direction of refrigerant in the first refrigerant flow channel, configured to allow the first refrigerant flow channel and the second refrigerant flow channel to communicate with each other.
2. The cooling head according to claim 1 , wherein the first refrigerant flow channel and the second refrigerant flow channel communicates with each other without a nozzle.
3. The cooling head according to claim 1 , wherein a downstream end of the second refrigerant flow channel in a second flow direction of refrigerant in the second refrigerant flow channel is blocked.
4. The cooling head according to claim 1 , wherein the second refrigerant flow channel is provided on the side of the first refrigerant flow channel opposite to the side in contact with the object.
5. The cooling head according to claim 1 , wherein the second refrigerant flow channel includes a plurality of flow channels for the object.
6. The cooling head according to claim 5 , wherein the plurality of flow channels extend parallel to each other.
7. The cooling head according to claim 5 , wherein the at least one communication hole is shared by at least two of the plurality of flow channels.
8. The cooling head according to claim 7 , wherein the at least one communication hole is formed so as to be elongate in a direction across the first flow direction.
9. The cooling head according to claim 1 , wherein the at least one communication hole includes a plurality of communication holes for the object, and the plurality of communication holes are arranged in the first flow direction.
10. The cooling head according to claim 1 , wherein the at least one communication hole is provided so as to correspond to the position of a hot spot having a large amount of heat generation of the object or is provided on an upstream side of the position of the hot spot.
11. The cooling head according to claim 1 , further comprising, a first flow channel member in which the first refrigerant flow channel is formed; and
a second flow channel member in which the second refrigerant flow channel is formed so as to form a stacked structure.
12. The cooling head according to claim 1 , wherein the refrigerant in the second refrigerant flow channel is merged with the refrigerant flowing through the first refrigerant flow channel at a communication position with the first refrigerant flow channel and flows to the downstream side.
13. An electronic apparatus comprising:
an electronic device; and
a cooling head configured to cool the electronic device, wherein the cooling head includes:
a first refrigerant flow channel, provided so as to be in contact with an object to be cooled, configured to flow refrigerant;
a second refrigerant flow channel configured to flow the refrigerant; and
at least one communication hole, provided between both ends of the object to be cooled in the first refrigerant flow channel in a first flow direction of refrigerant in the first refrigerant flow channel, configured to allow the first refrigerant flow channel and the second refrigerant flow channel to communicate with each other.
14. The electronic apparatus according to claim 13 , wherein a downstream end of the second refrigerant flow channel in a second flow direction of refrigerant in the second refrigerant flow channel is blocked.
15. The electronic apparatus according to claim 13 , wherein the second refrigerant flow channel is provided on the side of the first refrigerant flow channel opposite to the side in contact with the object.
16. The electronic apparatus according to claim 13 , wherein the second refrigerant flow channel includes a plurality of flow channels for the object.
17. The electronic apparatus according to claim 13 , wherein the at least one communication hole includes a plurality of communication holes for the object, and the plurality of communication holes are arranged in the first flow direction.
18. The electronic apparatus according to claim 13 , wherein the at least one communication hole is provided so as to correspond to the position of a hot spot having a large amount of heat generation of the object or is provided on an upstream side of the position of the hot spot.
19. The electronic apparatus according to claim 13 , further comprising, a first flow channel member in which the first refrigerant flow channel is formed; and
a second flow channel member in which the second refrigerant flow channel is formed so as to form a stacked structure.
20. The electronic apparatus according to claim 13 , wherein the refrigerant in the second refrigerant flow channel is merged with the refrigerant flowing through the first refrigerant flow channel at a communication position with the first refrigerant flow channel and flows to the downstream side.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2013002853A JP2014135396A (en) | 2013-01-10 | 2013-01-10 | Cooling head and electronic apparatus |
JP2013-002853 | 2013-01-10 |
Publications (1)
Publication Number | Publication Date |
---|---|
US20140190669A1 true US20140190669A1 (en) | 2014-07-10 |
Family
ID=51060097
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/051,521 Abandoned US20140190669A1 (en) | 2013-01-10 | 2013-10-11 | Cooling head and electronic apparatus |
Country Status (2)
Country | Link |
---|---|
US (1) | US20140190669A1 (en) |
JP (1) | JP2014135396A (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20180084673A1 (en) * | 2015-03-25 | 2018-03-22 | Mitsubishi Electric Corporation | Cooling device, power conversion device, and cooling system |
US10388589B2 (en) | 2015-11-25 | 2019-08-20 | Mitsubishi Electric Corporation | Semiconductor device, inverter device, and vehicle |
CN110610909A (en) * | 2018-06-14 | 2019-12-24 | 大众汽车有限公司 | Electronic component with improved cooling power and motor vehicle with electronic component |
EP3836204A1 (en) * | 2019-12-13 | 2021-06-16 | Valeo Siemens eAutomotive Germany GmbH | Cooling device for semiconductor switching elements, power inverter device and arrangement with a power inverter device and an electric machine |
US11310935B2 (en) * | 2017-05-17 | 2022-04-19 | Huawei Technologies Co., Ltd. | Heat dissipator and communications device |
WO2022139830A1 (en) * | 2020-12-23 | 2022-06-30 | Abaco Systems, Inc. | Impingement cooling providing enhanced localized cooling of a heatsink |
US20220404100A1 (en) * | 2021-06-18 | 2022-12-22 | Dana Canada Corporation | Two-pass heat exchanger with calibrated bypass |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2016048154A (en) * | 2014-08-28 | 2016-04-07 | パナソニックIpマネジメント株式会社 | Heat receiver and cooling device using the same and electronic apparatus using the same |
WO2016031227A1 (en) * | 2014-08-28 | 2016-03-03 | パナソニックIpマネジメント株式会社 | Heat receiver, cooling device using same, and electronic device using same |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5023695A (en) * | 1988-05-09 | 1991-06-11 | Nec Corporation | Flat cooling structure of integrated circuit |
US5239443A (en) * | 1992-04-23 | 1993-08-24 | International Business Machines Corporation | Blind hole cold plate cooling system |
US5270572A (en) * | 1991-06-26 | 1993-12-14 | Hitachi, Ltd. | Liquid impingement cooling module for semiconductor devices |
US5304845A (en) * | 1991-04-09 | 1994-04-19 | Digital Equipment Corporation | Apparatus for an air impingement heat sink using secondary flow generators |
US5316075A (en) * | 1992-12-22 | 1994-05-31 | Hughes Aircraft Company | Liquid jet cold plate for impingement cooling |
US5563768A (en) * | 1995-08-31 | 1996-10-08 | At&T Global Information Solutions Company | Heat source cooling apparatus and method utilizing mechanism for dividing a flow of cooling fluid |
US5576932A (en) * | 1995-08-31 | 1996-11-19 | At&T Global Information Solutions Company | Method and apparatus for cooling a heat source |
US6781834B2 (en) * | 2003-01-24 | 2004-08-24 | Hewlett-Packard Development Company, L.P. | Cooling device with air shower |
US7568519B2 (en) * | 2001-02-09 | 2009-08-04 | Kabushiki Kaisha Toshiba | Cooling device for heat source |
US7597135B2 (en) * | 2006-05-23 | 2009-10-06 | Coolit Systems Inc. | Impingement cooled heat sink with low pressure drop |
US20130233523A1 (en) * | 2012-03-08 | 2013-09-12 | International Business Machines Corporation | Cold plate with combined inclined impingement and ribbed channels |
-
2013
- 2013-01-10 JP JP2013002853A patent/JP2014135396A/en not_active Withdrawn
- 2013-10-11 US US14/051,521 patent/US20140190669A1/en not_active Abandoned
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5023695A (en) * | 1988-05-09 | 1991-06-11 | Nec Corporation | Flat cooling structure of integrated circuit |
US5304845A (en) * | 1991-04-09 | 1994-04-19 | Digital Equipment Corporation | Apparatus for an air impingement heat sink using secondary flow generators |
US5270572A (en) * | 1991-06-26 | 1993-12-14 | Hitachi, Ltd. | Liquid impingement cooling module for semiconductor devices |
US5239443A (en) * | 1992-04-23 | 1993-08-24 | International Business Machines Corporation | Blind hole cold plate cooling system |
US5316075A (en) * | 1992-12-22 | 1994-05-31 | Hughes Aircraft Company | Liquid jet cold plate for impingement cooling |
US5563768A (en) * | 1995-08-31 | 1996-10-08 | At&T Global Information Solutions Company | Heat source cooling apparatus and method utilizing mechanism for dividing a flow of cooling fluid |
US5576932A (en) * | 1995-08-31 | 1996-11-19 | At&T Global Information Solutions Company | Method and apparatus for cooling a heat source |
US7568519B2 (en) * | 2001-02-09 | 2009-08-04 | Kabushiki Kaisha Toshiba | Cooling device for heat source |
US6781834B2 (en) * | 2003-01-24 | 2004-08-24 | Hewlett-Packard Development Company, L.P. | Cooling device with air shower |
US7597135B2 (en) * | 2006-05-23 | 2009-10-06 | Coolit Systems Inc. | Impingement cooled heat sink with low pressure drop |
US20130233523A1 (en) * | 2012-03-08 | 2013-09-12 | International Business Machines Corporation | Cold plate with combined inclined impingement and ribbed channels |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20180084673A1 (en) * | 2015-03-25 | 2018-03-22 | Mitsubishi Electric Corporation | Cooling device, power conversion device, and cooling system |
US10271458B2 (en) * | 2015-03-25 | 2019-04-23 | Mitsubishi Electric Corporation | Cooling device, power conversion device, and cooling system |
US10388589B2 (en) | 2015-11-25 | 2019-08-20 | Mitsubishi Electric Corporation | Semiconductor device, inverter device, and vehicle |
US11310935B2 (en) * | 2017-05-17 | 2022-04-19 | Huawei Technologies Co., Ltd. | Heat dissipator and communications device |
US11641725B2 (en) | 2017-05-17 | 2023-05-02 | Huawei Technologies Co., Ltd. | Heat dissipator and communications device |
CN110610909A (en) * | 2018-06-14 | 2019-12-24 | 大众汽车有限公司 | Electronic component with improved cooling power and motor vehicle with electronic component |
EP3836204A1 (en) * | 2019-12-13 | 2021-06-16 | Valeo Siemens eAutomotive Germany GmbH | Cooling device for semiconductor switching elements, power inverter device and arrangement with a power inverter device and an electric machine |
WO2021115897A1 (en) * | 2019-12-13 | 2021-06-17 | Valeo Siemens Eautomotive Germany Gmbh | Cooling device for semiconductor switching elements, power inverter device and arrangement with a power inverter device and an electric machine |
US20230050543A1 (en) * | 2019-12-13 | 2023-02-16 | Valeo Siemens Eautomotive Germany Gmbh | Cooling device for semiconductor switching elements, power inverter device and arrangement with a power inverter device and an electric machine |
WO2022139830A1 (en) * | 2020-12-23 | 2022-06-30 | Abaco Systems, Inc. | Impingement cooling providing enhanced localized cooling of a heatsink |
US20220404100A1 (en) * | 2021-06-18 | 2022-12-22 | Dana Canada Corporation | Two-pass heat exchanger with calibrated bypass |
US11740028B2 (en) * | 2021-06-18 | 2023-08-29 | Dana Canada Corporation | Two-pass heat exchanger with calibrated bypass |
Also Published As
Publication number | Publication date |
---|---|
JP2014135396A (en) | 2014-07-24 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20140190669A1 (en) | Cooling head and electronic apparatus | |
US10718554B2 (en) | Manifold and information processing apparatus | |
US7597135B2 (en) | Impingement cooled heat sink with low pressure drop | |
JP5884530B2 (en) | RADIATOR AND ELECTRONIC DEVICE HAVING THE SAME | |
US9642287B2 (en) | Cooling plate and data processing system provided with cooling plates | |
US20140091453A1 (en) | Cooling device and semiconductor device | |
US10772234B2 (en) | Cooling device and electronic device system | |
US20150059388A1 (en) | Information processing apparatus | |
JP6191104B2 (en) | Refrigerant supply unit, cooling unit and electronic device | |
US20140284029A1 (en) | Cooler | |
JP5738503B1 (en) | Liquid cooling heat sink | |
JP2017150784A (en) | Sprinkler system | |
WO2013118809A1 (en) | Semiconductor cooling device | |
US20150369425A1 (en) | Vaporization device for low-temperature liquefied gas | |
JP2007333357A (en) | Cooler | |
JP5800429B2 (en) | Radiators in liquid cooling systems for electronic equipment | |
US10108235B2 (en) | Information processing apparatus and heat exchanger | |
US20180177079A1 (en) | Information processing device and electronic device cooling method | |
KR101917484B1 (en) | Piping structure, cooling device using same, and refrigerant vapor transport method | |
JP7119200B2 (en) | Cooling system | |
US9968007B2 (en) | Rack assembly | |
WO2012035571A1 (en) | Spray tube device and heat exchanger using same | |
JP6844499B2 (en) | Cooling device and semiconductor module equipped with it | |
JP7139656B2 (en) | Cooling system | |
US20190080984A1 (en) | Liquid-cooled type cooling device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: FUJITSU LIMITED, JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HOSHINO, YUKI;FUKUZONO, KENJI;REEL/FRAME:031386/0465 Effective date: 20130918 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |