WO2006107126A1

WO2006107126A1 - Circuit connecting apparatus using integrated silicone contactor.

Info

Publication number: WO2006107126A1
Application number: PCT/KR2005/001411
Authority: WO
Inventors: Jong-Cheon Shin
Original assignee: Isc Technology Co., Ltd.
Priority date: 2005-04-07
Filing date: 2005-05-13
Publication date: 2006-10-12
Also published as: TWM285068U

Abstract

A circuit connecting apparatus, in which the integrated silicone contactor as described above is used as an interposer, so that without the male and female connectors a mother board and a daughter board can be connected to each other. This invention comprises a (5) mother board, on which a plurality of contact pads formed on a region where the daughter board is to be connected; a silicone contactor which is put on the mother board, the silicone contactor having conductive parts vertically embedded to correspond to the pads of the mother board, such that the conductive parts contact to the pads of the mother board; a daughter board which is put on the silicone contactor, the daughter board having contact (10) pads on the place where they correspond to the conductive parts of the silicone contactor, and engaging means, which is put on the daughter board, for pressing down the daughter board and the silicone contactor to the mother board, such that all of these components can be firmly contacted to one another.

Description

Circuit Connecting Apparatus Using Integrated Silicone Contactor

Technical Field

The present invention relates to a novel circuit connecting apparatus using "a silicone contactor" that the present applicant owns as a exclusive right, Korea Patent No. 448414, Korea Utility Model Nos. 278989, 312739, 368242, and 368243.

Background Art

First, the applicant's basic prior art, the Patent No. 448414, will be briefly discussed. As in Fig. 1, a silicone contactor 13 comprises a conductive silicone part 5 and an insulative silicone part 7. The former is formed so as to contact with a lead terminal 27 of a semiconductor device 21; the latter is formed so as not to contact with the lead terminal 27 so that it may insulatively support the conductive parts 5. Such a silicone contactor 13 electrically connects, as a medium, the lead terminals 27 of the semiconductor device 21 with contact pads 26 of a socket board 28 which performs the test of semiconductor devices. In this prior art, since the conductive parts 5 and the lead terminals 27, and also the conductive parts 5 and the contact pads 26 elastically contact to each other, there arise no contact failure or high contact-resistance between the contact interfaces. Moreover, since there is little mechanical abrasion, long life span can be guaranteed. In Fig. 1, it is shown that a bottom surface 19 of the conductive silicone part 5 is projected by "h" (around 20-5 Oum) from the insulative silicone part 7, in order to enhance the contact between the conductive part 5 and contact pad 26.

Now, a conventional circuit connecting method, which is the object of the present invention, will be described. In particular, the present invention intends to improve the conventional "board-to-board" connection method shown in Fig. 2.

In the board-to-board connection of Fig. 2, a daughter board 13 is engaged with a mother board 10. Here, the mother board 10 is of rigid material like a printed circuit board, and the daughter board 13 is, but not limited to, a flexible printed circuit (FPC). In Fig. 2, a female connector or receptacle 14 is mounted on the mother board 10, while a corresponding male connector or plug 12 is mounted on the daughter board 13, or vice versa. To connect the daughter board 13 to the mother board 10, the male connector 14 is inserted in the female connector 12. A variety of connecting structures of the female and male connectors 14 and 12 may be implemented. Typically, the female and male connectors 14 and 12 are interconnected through the physical engagement of elastic contactors. From the foregoing, in the conventional art, the physical connection between the female and male connectors is supported by the mechanical structure that they have in nature.

However, the problem of the conventional circuit connection method of Fig. 2 is that, the frequent use of it causes the mechanical connecting force to be weaker. This is because of corrosion of the elastic metal contactor, deterioration of elastic force, oxidization by spark, etc. These increase the contact resistance on the surface of the contactor.

Especially, a micro-pitch connector, which generally constitutes a pair, is made up of contact pins made from bronze, Be-Cu, etc., which is fixed by insulators (such as corrosion-resistant, anti-chemicals, high stiffness, high insulative engineering plastics). Normally, this pin type of connector, which consists of a male and a female, is mounted on a circuit board by means of soldering. However, this kind of connector has mechanical structure that is very difficult to be made under 0.4mm pitch. Besides it has further drawbacks as follows: 1) soldering process is required when manufacturing, 2) when soldering the micro-pitch (less than 0.5mm) connector, it may cause the pins to be short- circuited or open. It is impossible to repair this, and instead the whole unit including the connector must be replaced, 3) resistive constituent included in the solder worsens the frequency characteristics, 4) solder, i.e., lead, has an influence on the environment.

Disclosure of Invention

It is an object of the present invention to overcome the above problem of the conventional pin type connector. The present invention provides a circuit connecting apparatus, in which the integrated silicone contactor as described above is used as an interposer, so that without the male and female connectors a mother board and a daughter board can be connected to each other.

To achieve the above object, the present invention provides an apparatus for connecting circuit boards, comprising a mother board, on which a plurality of contact pads formed on a region where the daughter board is to be connected; a silicone contactor which is put on the mother board, the silicone contactor having conductive parts vertically embedded to correspond to the pads of the mother board, such that the conductive parts contact to the pads of the mother board; a daughter board which is put on the silicone contactor, the daughter board having contact pads on the place where they correspond to the conductive parts of the silicone contactor; and engaging means, which is put on the daughter board, for pressing down the daughter board and the silicone contactor to the mother board, such that all of these components can be firmly contacted to one another.

According to one feature of the present invention, the engaging means comprises a penetration hole formed at the periphery of the contact pads of the mother board; and a clamp having a locking hook inserted into the penetration hole of the mother board. According to another feature of the present invention, the engaging means comprises a frame which is surface-mounted on the mother board; and a clamp having a locking hook inserted into a recess formed on a side wall of the frame.

It is preferable that a guide pin is installed on the lower surface of the clamp, and a guide hole, to which the guide pins are inserted, is formed on the mother board, silicone contactor and daughter board.

From the foregoing, since the present invention basically adopts a silicone contactor, which was described before, as an interposer to connect the mother board and the daughter board, the following advantages are obtained:

1) Since there is no connector on the mother board but a connector exists only on the daughter board without male and female connectors, the manufacturing process is simplified.

2) Since soldering is unnecessary to connect the mother board and the daughter board, it has an affinity for environment and the repairing or replacement of a unit due to soldering failure is unnecessary.

3) Separation of the mother board and the daughter board is easy, and since it does not need soldering, reuse is possible.

4) Because the preciseness of manufacturing equipments may be unsophisticated, the cost to development can be reduced by 50% or less.

5) The new product developing time can be shorted by two weeks or two months than for the conventional pin type connector.

6) Because there is no abrasion of the contact points, the lifetime can be far more lengthened. In addition to the above advantages, the elasticity of the silicone contactor helps the contact force, and thereby the contactibility can be more strengthened. At the same time, since just a simple action for pushing the locking head is required, workability can be improved. Also, when in failure, it is only necessary to replace the relevant component, thereby the maintenance costs being reduced.

Brief Description of the Drawings

The above and other objects, features, and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings, in which:

Fig. 1 explains a concept of an integrated silicone contactor that the inventor owns as a prior art right,

Fig. 2 shows an example of a conventional pin type connector, Fig. 3 is an exploded view of one embodiment of the present invention, Fig. 4 is a longitudinal cross section of the embodiment of the present invention,

Fig. 5 is an exploded view of another embodiment of the present invention.

Preferred Embodiments for Carrying out the Invention

Now construction and operation of a circuit connecting apparatus using an integrated silicone contactor in accordance with the present invention will be discussed in detail.

First embodiment

With reference to Fig. 3, it is shown a mother board 100, on which a pad region 102 including a plurality of contact pads is formed and at least two or more penetration holes 104 are formed at the periphery of the pad region 102. Reference numeral 112 is a daughter board. The mother board 100 may be a rigid PCB (printed circuit board), while the daughter board 112 may be a relatively flexible circuit board. However, these are not limited to this. For example, the daughter board 112 may also be a rigid circuit board, and otherwise a cable or a wire harness, etc.

A silicone contactor 106, which was already explained with Fig. 1, is put on the mother board 100. The silicone contactor 106 is made so as not to cover the penetration hole 104. At the silicone contactor 106, conductive parts 108 are vertically embedded to correspond to the pads of the pad region 102. In Fig. 3 which is a specific example, recesses 110 are included on the opposing sides of the silicone contactor 106, but the recesses 110 are not indispensable as long as the silicone contactor 106 does not cover the penetration hole 104 of the mother board 100. The conductive parts 108 contact the pads of the mother board 100.

The daughter board 112 is put on the silicone contactor 106. The daughter board 112 includes contact pads 114 on the place where they correspond to the conductive parts 108 of the silicone contactor 106. As stated before, the daughter board 112 may be a FPC (flexible printed circuit board), FFC (flexible flat cable), a wire harness, or even a rigid PCB. The daughter board 112 also has recesses 116 corresponding to the location of the penetration hole 104, but the recesses 116 are not indispensable as long as the silicone contactor 106 does not cover the penetration hole 104 of the mother board 100.

A clamp 118 is put on the daughter board 112, which has at least two or more locking hooks 122 inserted into the penetration hole 104 of the mother board 100. The clamp 118 is made from a relatively rigid material, such as plastics or metal, but not limited to this. The clamp 118 presses down the daughter board 112- and silicone contactor 106 to the mother board 100, and thereby once the locking hook 122 is engaged with the penetration hole 104, all of the components 100, 106, 112 can be firmly contacted to one another.

The engaged feature is shown in Fig. 4. Comparing with the conventional circuit connection shown in Fig. 2, since there are no elastic contactors and housing, far longer lifetime can be obtained. In addition, when the components 100, 106, 112 are strongly contacted to one another, the elasticity of the silicone contactor 106 helps the contactibility between them.

The structure and operation of the clamp 118 will be described with reference to Fig.

4. In Fig. 4, the clamp 118 has at least two locking hook 122 which are downward inserted to the penetration hole 104 of the mother board 100. The locking hook 122 generally shapes a column and downward projects from the clamp 118. The lower end of the locking hook

122 forms a barb 123 of which the bottommost thickness is smaller than the diameter of the penetration hole 104 but as going up the thickness is growing so as to be larger than the diameter of the penetration hole 104. Therefore, if pressing the clamp 118 downward, the locking hook 122 is pushed into the penetration hole 104, and after a given depth, the barb

123 is locked on the body of the mother board 100. Once locked, the clamp 118 cannot be separated from the mother board 100 by its own strength.

If the length of the locking hook 122 is made to be slightly shorter than the thickness of the combination of the mother board 100, silicone contactor 106 and daughter board 112, all of these components will be more firmly contacted between the barb 123 and the bottom surface of the clamp 118. Further, since the silicone contactor 106 has elastic property, the length of the locking hook 122 can be shorten more, thereby the extent of the components' contact becoming more firm.

In the meantime, unexplained elements "124" and "126" in Fig. 3 will be described. If using the circuit connecting apparatus according to the present invention as a micro -pitch connector, it is very important to align the mother board 100, silicone contactor 106 and daughter board 112 to an exact position. For this, the present invention may include a position aligning means. For example, guide pins 126 are installed on the lower surface of the clamp 118, and guide holes 124, to which the guide pins 126 are inserted, are formed on the mother board 100, silicone contactor 106 and daughter board 112. The guide pin and guide hole may be formed single each, but preferably be two or more. Fig. 3 shows that the four guide pins and guide holes are formed.

Second embodiment

Fig. 5 is an exploded view of another embodiment of the present invention. In the embodiment shown in Fig. 3, the penetration hole 104 was formed in the mother board 100 to be engaged with the clamp 118.

However, in Fig. 5 embodiment, there is no penetration hole in the mother board 100, and instead, a frame 128 is surface-mounted on the mother board 100. The daughter board 112 and a silicone contactor 106' are contacted to the mother board 100 by locking a clamp 118 to the frame 128.

The shape of the frame 128 mounted on the surface of the mother board 100 may be optional, as long as it has recesses 105, to which the locking hook 122 of the clamp 118 is inserted and locked, on the side walls, which surround the contact pads of the mother board 100, of the frame 128. In Fig. 5, the frame 128 is made into a housing shape, but not limited to this. The manner of mounting the frame 128 is also optional. It may be soldered or assembled on the mother board 100 by means of SMT (surface mounting technique) or fastening means such as a screw, rivet, etc. As this embodiment, if the frame 128 is made as a housing shape, the housing side walls are slightly elevated. So, to meet this height difference, the thickness of the silicone contactor 106' should be increased comparing to that of the silicone contactor 106 in Fig. 3. In addition, the projecting length of the guide pins 126' may be also heightened more. Compare Fig. 3 and Fig. 5. This modification can be easily implemented by those who skilled in the relevant art.

In this embodiment, the operation of the locking hook 122 of the clamp 118 is similar to that of Fig. 3. So, further explanation is omitted. The configuration of the recesses 105 formed in the side walls of the frame 128 and the configuration, length, etc. of the locking hook 122 may be decided by those who skilled in the art, by simply considering the height difference and contact force between the silicone contactor and the daughter board.

Thus far, while the invention has been shown and described with reference to certain embodiment to carry out this invention, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

What Is Claimed Is:

1. An apparatus for connecting a daughter board to a part of mother board, comprising: a mother board, on which a plurality of contact pads formed on a region where the daughter board is to be connected, a silicone contactor which is put on the mother board, the silicone contactor having conductive parts vertically embedded to correspond to the pads of the mother board, such that the conductive parts contact to the pads of the mother board, a daughter board which is put on the silicone contactor, the daughter board having contact pads on the place where they correspond to the conductive parts of the silicone contactor, and engaging means, which is put on the daughter board, for pressing down the daughter board and the silicone contactor to the mother board, such that all of these components can be firmly contacted to one another.

2. The apparatus of claim 1, wherein the engaging means comprises: a penetration hole formed at the periphery of the contact pads of the mother board, and a clamp having a locking hook inserted into the penetration hole of the mother board, the locking hook being downward inserted to the penetration hole of the mother board, the locking hook generally shaping a column and downward projects from the clamp, whereby the lower end of the locking hook forms a barb, and if pressing the clamp downward, the locking hook is pushed into the penetration hole and locked on the body of the mother board.

3. The apparatus of claim 1, wherein the engaging means comprises: a frame which is surface-mounted on the mother board, and a clamp having a locking hook inserted into a recess formed on a side wall of the frame, whereby the lower end of the locking hook forms a barb, and if pressing the clamp downward, the locking hook is locked to the recess.

4. The apparatus of claim 3, wherein the frame shapes a housing form having side walls surroi'nding the contact pads on the mother board, and wherein the recess is recessively formed on the side walls.

5. The apparatus of any one of claims 1 to 4, further comprising: a guide pin installed on the lower surface of the clamp, and a guide hole, to which the guide pins are inserted, formed on the mother board, silicone contactor and daughter board.

6. The apparatus of any one of claims 1 to 4, wherein the mother board is a printed circuit board, and the daughter board is a flexible circuit board.