US2735602A - Apparatus for unseating milk can covers - Google Patents

Description

Feb. 21, 1956 w, w s

APPARATUS FOR UNSEATING MILK CAN COVERS 3 Sheets-Sheet 1 Filed April 27, 1953 IN V EN TOR. WESLEY VVISE Feb. 21, 1956 w, WISE APPARATUS FOR UNSEATING MILK CAN COVERS 3 Sheets-Sheet 2 Filed April 27, 1955 KNOCKER FRAME A/R VALVE INVENTOR. WESLEY VVIJ'E' BY @MQQWAW ATTORNEKS Feb. 21, N56

W. WISE APPARATUS FOR UNSEATING MILK CAN COVER:

Filed April 27. 1953 3 Sheets-Sheet. 3

KNocKEk CYLINDER KNOCKER FRAME HIGH PRESSURE All? TRANSFORMER i mvoc/rsk INVENTOR. WESLEY l/V/SE ATToR/vE-Ks United States Patent APPARATUS FOR UNSEATING MILK CAN COVERS Wesley Wise, Kiel, Wis,

Application April 27, 1953, Serial No. 351,349

8 Claims. (Cl. 226129) This invention relates to an improved apparatus for automatically unseating milk can covers from their respective can tops as the cans are advanced by a conveyor to their destination.

In the operation of .a creamery the raw milk is usually brought into the creamery in conventional milk cans having their .open tops closed by suitable covers. Milk cans utilize two diflerent and distinct types of covers, one commonly known as the umbrella type, and the other as a plug type. These covers have a portion fitted into the cylindrical neck of the can top and are retained in sealing engagement therewith by friction.

The present invention is directed to an apparatus for unseating milk can covers of the type having their outer marginal edges projecting slightly beyond the perimeter of their respective can tops, whereby the projecting marginal edges of the can covers may be engaged by a knocker, or the like, for the purpose offreeing or unseating the covers from their seats to facilitate the subsequent removal of the covers from the cans in the operation of emptying the filled cans into a suitable receptacle or weigh can.

In the initial step of processing raw milk, the filled cans are usually placed upon a suitable conveyor for transporting them from the unloading dock or platform to a receiving room or station where the milk may be dumped into a conventional weigh can by an operator stationed adjacent thereto. Heretofore it has been customary to have an attendant stationed alongside the conveyor to manually unseat each cover so that when :the cans reach the operator at the weigh .can, he may, with- .outinterruption, remove the cover and dump the .con-

tents of each can into the weigh .can. By the employment of the present invention the services :of the attendant for manually unseating the cancovers may be dispensed with, as the present invention automatically .unseats each can cover and leaves it loosely disposed-on .top of the can in a canted position whereby .the .operator at the weigh can may readily remove the loose covers .and dump the contents of the cans into the weigh can.

An important object of the present invention, .therefore, is to provide an apparatus for automatically .unseating the covers of milk .cans as they are successively conveyed to a suitable receptacle or weighcan, without interrupting the traveling movement of the cans.

A further and more specific object of the invention is to provide, in combination with a suitable conveyor, an apparatus comprising a knocker having an operating mechanism which is controlled by movement of the .cans to automatically eifect actuation of the knocker and cause it to engageiand unseat each cover from their respective can tops, as the cans are successively conveyed through the apparatus to the weigh can.

A further object is to provide an apparatus for unseating milk can covers from cans being conveyed by a suitable conveyor from one station to another, which apparatus comprises a suitable supporting structure disposed over the conveyor and having 'a membermounted ice for vertical sliding movement therein and provided at its lower end with inwardly turned portions, which will hereinafter be termed knockers. These knockers are normally positioned beneath the path of travel of the opposed marginal edge portions of the milk can covers, when the covers are in their normal closed positions on their respective cans, and are automatically actuated by a fluid-operated mechanism which is controlled by the movement of the cans, and whereby as each can passes the knockers, said fluid operated mechanism ,is .automatically actuated to cause the knockers to operate .and unseat the can covers.

A further and more specific object of the invention is to provide an apparatus for unseating milk can covers, comprising a conveyor having a knocker frame mounted for vertical sliding movement thereover, said knocker frame being operatively connected to a fluid actuated mechanism comprising a plurality-of electric control elements adapted to be actuated by the movements of the .cans and the knocker frame to automatically control the operation of the knocker frame.

Other objects of the invention reside in the simple and inexpensive construction of the apparatus; in the provision of such an apparatus which will unseat the can covers with a positive action, as the cans are successively fed thereto; and in the provision of such an apparatus wherein the can cover engaging elements, when actuated, engage the cover with a hammer-like action, thereby to completely unseat each cover regardless of its frictional engagement with the can neck.

These and other objects of the invention and the means :for their attainment Will be more apparent from the following description taken in connection with the accompanying drawings.

In the accompanying drawings there has been disclosed'astructure designed tocarry out the various objects of the invention, but it is to be understood that the invention is not confined to the exact features shown, as various changes may be made within the scope of the claims which follow.

In the drawings:

Figure 1 is a longitudinal vertical sectional view on the line 11 of Figure 2, showing the invention positioned over the path of travel of the milk cans;

Figure 2 is a sectional elevation on the line '22 of Figure 1, showing in full and dotted lines the two positions of the knockers with reference to the can'covers;

Figure 3 is a sectional plan view on the line 3-3 of Figure 2; and

Figure 4 -is a diagrammatic view illustrating the oper ating and control mechanism for the knockers.

In the selected embodiment of the invention herein disclosed, there is illustrated in Figures 1, 2, and 3, for the purposes 'of disclosure, a portion of a conveyor, generally designated by the numeral 2, comprising a .flexible conveying element 3, .which may be in the form of an endless chain or belt supported upon suitable sprockets or pulleys, not shown in the drawings. In the present instance, a single conveyor element 3 isemployed, but it is to be understood that two or more may be imountedz-in parallel relation, .if deemed necessary. Longitudinally extending bottom rails 44 are provided at .each side of the conveyor element 3 adapted to be engaged by the can bottoms as will be understood by reference to Figures 2 and 3. Guide rails 55 are also provided for retaining the containers or can 6 in position on the conveyor as will be understood.

,An important feature of the present invention relates in the novel means provided for unseating the cover 7 from .each can top, as the cans travel uninterruptedly from the unloading platform, not shown, to their designation, such as the usual weigh can or bucket into which the contents of the cans is dumped by an attendant stationed adjacent thereto.

To thus unseat the can covers, a supporting structure generally designated by the numeral 8, is provided over the conveyor 2 and comprises upright frame members 9-9 having their lower ends suitably secured to the guide rails 5-5 by such means as welding, rivets or bolts. The upper ends of the upright frame members 9--9 are secured together in spaced relation by a suitable cross member or header 11.

Slidably mounted within the supporting structure 8 is a rectangular knocker frame, generally designated by the number 12, comprising side members 13-43 and a top member 14, which members may be formed from a single bar of strap iron to facilitate construction. The side members 1313 of the knocker frame are slidably supported in suitable guides 15 secured to the inner faces of the upright frame members 99, as indicated in Figure 2, whereby said guides cooperate to vertically guide the knocker frame in its up-and-down movements, as will subsequently be described.

As best illustrated in Figure 2, the lower ends of the side members 1313 of the knocker frame are bent inwardly at substantially right angles to provide knocker elements 1616 adapted to engage the outer marginal edge portions of each can cover with sufficient impact to unseat the covers as illustrated in dotted lines in Figure l, as the cans successively pass the knocker.

Conventional milk cans utilize two types of covers, one known as the umbrella type and the other the plug type. Both types are retained in closed positions in the can top by friction, and because of their relatively large diameter, sometimes require considerable force to unseat them. Heretofore an operator has been stationed alongside the conveyor for manually unseating-the covers, as the filled cans are conveyed toward the weighing can. In some instances, it has been extremely difiicult for an attendant to thus manually unseat each cover without at times interrupting the travel of the cans, particularly if some of the covers have been slightly deformed so as to increase their frictional engagement with, their respective can tops.

The present invention eliminates the operation of thus manually unseating the covers and insures complete unseating of each can cover or closure without interruption or failure. Of the two types of can covers above referred to, the umbrella type is the most popular, and such a cover is therefore illustrated in the accompanying drawings.

To insure positive unseating of each can cover, means is provided for imparting a hammer-like blow to each cover as the cans are conveyed towards the weigh can or milk dumping station. Such means is shown comprising a pair of inturned knocker terminals 1616, provided at the lower end of the knockcr frame and adapted to engage the perimeter of each can cover at opposite sides with a hammer-like blow, thereby to unseat each cover, as illustrated in Figures 1 and 2. The knocker terminals may be integrally formed with the lower ends of the side members 1313 of the knocker frame 12, as shown in Figure 4'. i

To thus actuate the knocker, a pneumatic cylinder 17 is shown mounted in the supporting frame 8 by suitable cross members 18 and 19 having their terminals secured to the upright frame members 99 by suitable means, not shown. A piston 21 is mounted within the cylinder 17 and has a rod 22 projecting from the upper end of the cylinder which is operatively connected to the upper member 14 of the knocker frame 12, as illustrated in Figures 2 and 4.

To cause the knocker frame to impart a hammer-like blow to each can cover, means is provided for introducing a high pressure fluid into the lower end of the cylinder 17, below the piston 21, such as compressed air. To thus direct the flow of high pressure air to and from the opposed ends of the cylinder, an electrically operated valve device is shown mounted in the lower portion of the cylinder, and comprises opposed solenoids 23 and 24 operatively connected to a slide valve 25 mounted in a cylindrical valve chamber 26, as indicated in Figure 4. A conduit 27 has one end in communication with the valve chamber 26 and has its opposite end connected to a source of air under pressure.

A passage 28 establishes communication between the valve chamber 26 and the lower end of the cylinder 17 below the piston 21, and a passage 29 connects the valve chamber 26 with the upper end of the cylinder, as indicated at 31, in Figure 4. The lower ends of the passages 28 and 29 are so spaced with respect to the length of the control valve 25 that the passages 28 and 29 are alternately opened and closed during operation of the apparatus, by energization of the solenoids 23 and 24 by the control means, next to be described.

The control means is best illustrated in Figure 4, and comprises a pair of suitable control switches, generally designated by the numerals 32 and 33, which are normally in circuit-opening positions, as indicated in Figure 4. Control switch 32 is suitably secured to one of the upright frame members 9 of the supporting structure, and comprises a fixed contact 34 and a movable contact 35. The movable contact 35 is adapted to be moved into electrical contact with the fixed contact 34 by actuation of an arm 36 having an anti-friction roller 37 mounted at the outer end thereof normally positioned in the path of each can body, whereby as the cans successively pass the switch 32, said switch is momentarily closed to effect energization of the solenoid 23.

Electric energy is supplied to the solenoids 23 and 24 from a suitable transformer 38 having its primary connected to a suitable source of electric energy, not shown, by conductors 39 and 41. One side of the secondary of the transformer has a wire 42 connecting it to a wire 43 which is electrically connected to the fixed contacts of the control switches 32 and 33, as clearly illustrated in the wiring diagram, Figure 4. The other side of the secondary has a wire 44 connecting it to a wire 45 which is electrically connected to the windings of the solenoids 23 and 24. A wire 46 connects the movable contact 35 of control switch 32 to the winding of solenoid coil 23, thus providing a circuit therefor.

The upper control switch 33, like the lower control switch 34, comprises a fixed contact 47 and a movable contact 48 which has an arm 49 carrying an anti-friction roller 51, normally positioned in the path of the knocker frame 12, whereby when said frame is moved upwardly by actuation of the piston 21, the control switch 33 is momentarily closed to effect energization of the solenoid 24 through a wire 52.

In the operation of the novel apparatus herein disclosed, the cans are delivered onto the conveyor 2 in spaced relation, as indicated in Figure 1, and as each can passes through the supporting frame 8, it engages the roller 37 of the movable contact 35 of the lower control switch 32, whereupon contact 35 enggaes contact 34 and completes a circuit to solenoid 23 through wires 42 and 43, contacts 34 and 35, wire 46 to one end of the winding of solenoid 23, thence through a portion of wire 45 and through wire 44 to the other side of the secondary of transformer 38.

Such eneregization of solenoid 23 instantly shifts the slide valve 25 to the position indicated in dotted lines in Figure 4, whereby communication is established between the lower end of cylinder 17 and the high pressure conduit 27, through the passage 28 and valve chamber 26, whereby the piston is suddenly forced upwardly and causes the knocker terminals 16 to impinge against the overhanging perimeter of the can cover 7 with a hammer-like action, which positively unseats the cover and leaves it resting loosely upon the open top of the can, as illustrated at the lefthand end of Figure 1.

As the knocker frame is thus moved upwardly to unseat a can cover, the upper portion thereof engages the roller 51 of control switch 33, whereby a circuit is completed to solenoid 24 through wires 42 and 43, contacts 47 and 48, Wire 52 to one end of the winding of solenoid 24, thence through a portion of wire 45 and through wire 44 -to the other side of the secondary of transformer 38. When the solenoid 24 is thus energized, the slide valve 25 is shifted to the opposite end of the valve chamber 26 and thereby establishes communication between =the air supply conduit 27 and the upper end of the cylinder through the passage 29, thereby effecting a positive return movement of the knocker frame to its normal position. It is to be understood that the lower control switch 32 is opened while the knocker frame is in its upper position so that the solenoid 23 is deenergized to permit the solenoid 24 to actuate the slide valve 25.

The pneumatically operated control device herein disclosed, including cylinder 17, piston 21 and solenoids 23 and 24. is well known in the art, and is readily available upon the market, and it is therefore believed unnecessary to herein further describe the same in detail.

To afford a clearer understanding of the operation of this particular pneumatic control device, it may be well, however, to briefly describe the construction and operation thereof. It utilizes a valve piston 52 slidably mounted in the upper end of the cylinder 17 above an intermediate cylinder head 53, indicatedin dotted lines in Figure 4. When the piston 21 is in its normal lowered or retracted position, high pressure air enters the upper end of cylinder 17 above valve piston 52 through duct 29 and thus drives valve piston 52 downwardly until it seats against the intermediate cylinder head 53. Check valve means is provided in the valve piston 52 for permitting high pressure air to pass through valve piston 52 into the lower portion of the cylinder, thereby to drive the piston 21 to its fully retracted position.

When the slide valve 25 is shifted to advance position by energization of solenoid 23, high pressure air flows into cylinder 17 through port 28 which drives piston 21 upwardly in the piston. Such action of piston 21 compresses the air trapped in cylinder 17 between piston 21 and valve piston 52, until the pressure of such air becomes sufiicient to unseat valve piston 52 from the intermediate head 53, whereupon the trapped air is instantly released to the atmosphere through suitable ducts, not shown.

The novel apparatus herein disclosed has been found extremely practical and efficient in actual operation. It is controlled by movement of the cans through the upright supporting frame or structure 8, as a result of the can bodies successively engaging the contact roller 37 of the lower control switch 32. The knocker frame is also returned to its normal position by air pressure as a result of the upper control switch 33 being closed by upward movement of the knocker frame, thereby to direct the high pressure air to the opposite end of the piston to cause it to return to its normal lowered position. A suitable bumper element 53 may be secured to the upper cross member 14 of the knocker frame to cushion its engagement with the upper cross bar 11 of the supporting frame. Similar cushion elements 54 are shown secured to brackets 55 for limiting the downward movement of the knocker frame, as will be understood by reference to Figures 1 and 2.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, but the appended claims should be construed as broadly as permissible in view of the prior art.

I claim as my invention:

1. In an apparatus of the class described, conveyor 6 means for transporting containers from one place to another, and each container having a cover frictionally .secured thereto, a supporting structure mounted over the conveyor, knocker means movable in said supporting structure and engageable with opposite sides of the can cover, and means controlled by movement of the containers to automatically effect operation of said knocker means to unseat each container cover, as the containers successively pass said knocker.

2. In an apparatus according to claim 1, wherein two control elements are provided for controlling the operation of the knocker, one of said control elements being operable by traveling movement of the container to initiate operation of the knocker, and the other of said control elements being positioned to be engaged by the knocker to effect return movement of the knocker after unseating a cover.

3. In an apparatus of the class described, a conveyor for transporting filled containers from one station to another, each of said containers having a closure frictionally secured in the open top thereof, said closures having their perimeters extending slightly beyond the upper marginal rims of their respective container tops, a supporting structure mounted over the conveyor, 21 knocker mounted for vertical sliding movement in said supporting structure, means for actuating said knocker including a fluid-operated device having a connection with a source of fluid under pressure, and a control element positioned to be engaged by each container passing beneath said knocker, thereby to effect the admission of pressure fluid to said device and cause it to operate the knocker and automatically unseat the closure from the container top.

4. In an apparatus according to claim 3, wherein the control means for said knocker includes a pair of vertically spaced control elements, one being positioned to be engaged by traveling movement of the container to initiate operation of the knocker, and the other being engageable with the knocker to effect the return movement thereof.

5. In an apparatus of the class described, a conveyor for transporting milk cans from one station to another, the open top of each can having a cylindrical neck and the can closure having a depending skirt fitting into said neck and provided at its upper end with an umbrellalike top wall having its perimeter projecting slightly beyond the perimeter of the can top, a supporting structure over the conveyor having vertically disposed guides therein, a knocker comprising a rectangular frame mounted for sliding movement in said guides, said knocker frame being provided at its lower end with inturned terminals normally positioned beneath the path of travel of the perimeters of the milk can closures, a pneumatic cylinder fixedly mounted in the supporting structure and having a piston therein having one end connected to the knocker frame, means for conducting air under pressure to said cylinder to actuate the piston and said knocker and cause the terminals of the knocker to simultaneously impinge against the perimeter of a can closure with a hammerlike action, thereby to unseat the closure from the can top.

6. In an apparatus according to claim 5, wherein means is provided for returning the knocker to its normal position by fluid pressure.

7. In an apparatus according to claim 6, wherein a solenoid-actuated valve is provided for controlling the supply of air under pressure to and from the cylinder, the operation of said valve being automatically controlled by alternate actuation of vertically spaced switch elements having electrical connections with said solenoidactuated valve and with a source of electrical energy, one of said switch elements being positioned to be actuated by traveling movement of the milk cans to effect operation of the knocker and cause it to engage and un seat the closure of each can passing thereby, and the other of said switch elements being engageable with the knocker to efiect the return movement of said knocker.

8. In an apparatus of the class described, a conveyor for transporting milk cans from one station to another, a supporting structure over the conveyor having vertically disposed guides therein, a knocker comprising a rectangular frame mounted for sliding movement in said guides and comprising top and side members, said side members being provided at their lower ends with inturned terminals normally positioned beneath the path of travel of the perimeters of the milk can closures when said closures are in normal closed positions, a pneumatic cylinder fixedly mounted in the supporting structure and having a piston projecting from the upper end thereof and secured to the top member of the knocker frame,

References Cited in the file of this patent UNITED STATES PATENTS 1,922,772 Lathrop Aug. 15, 1933 2,184,117 Fechheimer Dec. 19, 1939 2,570,186 Almgren Oct. 9, 1951 2,612,065 Packer et al. Sept. 30, 1952 M 1,4,, we,

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