US2760702A

US2760702A - Can transfer valve with pressurized seat

Info

Publication number: US2760702A
Application number: US370726A
Authority: US
Inventors: Pechy William
Original assignee: American Can Co
Current assignee: Primerica Inc
Priority date: 1953-07-28
Filing date: 1953-07-28
Publication date: 1956-08-28
Anticipated expiration: 1973-08-28

Description

Aug. 28, 1956 w. PECHY 2,760,702

CAN TRANSFER VALVE WITH PRESSURIZED SEAT Filed July 28, 1953 2 Sheets-Sheet 2 INVENTOR. WIL'LIAM PECHY 0/ 6/45 ATTORNEYS United States Patent CAN TRANSFER VAQEETWI'II-I PRESSURIZED William Pechy, Belmar, N. J., assignor to American Can Company, New York, N. Y., a corporation of New Jersey Application July 28, 1953, Serial No. 370,726

6 Claims. (Cl. 226-68) The present invention relates to a container or can transfer mechanism and has particular reference to rotating transfer valves used for passing cans into and out of pressurized compartments of can closing machines.

Machines used for closing cans under a vacuum or a gas pressure usually are equipped with rotary cylindrical transfer valves having peripherally disposed and spaced pockets for receiving the cans during transfer into and out of a pressurized closing compartment. In some machines only a can vacuum or gassing operation is required while in other machines the cans are first vacuumized and then gassed before closing. In order to increase the efiiciency of such machines initial or preliminary vacuumizing and/or gassing of the cans is effected during their transfer while the cans are in the valve pockets.

Since a slight annular clearance space between the valve and its cylindrical seat is required to provide for free rotation of the valve, free or atmospheric air usually passes between the valve and its seat and leaks into the valve pockets during the prevacuumizing and/or pregassing operation with the result that the vacuum and/ or gas is diluted or reduced and the efficiency of the machine impaired.

The instant invention contemplates overcoming this difficulty by vacuumizing and/or gassing the space between the valve and its seat to prevent leakage of air into the valve pockets.

An object of the instant invention is the provision of a rotary valve can transfer mechanism for pressurized compartments wherein any space between the valve and its seat is pressurized to prevent leakage of air into the valve pockets so as to increase the efiiciency of prepressurizing the pockets and the cans therein during their transfer.

Another object is the provision of such a transfer mechanism wherein sufiicient space between the valve and its seat may be obtained to permit of free rotation of the valve with a resulting decrease in the wearing of the valve and seat faces without leakage of air through the space and into the valve pockets.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

Figure l is a vertical section taken through a rotary valve can transfer mechanism embodying the instant invention, with parts broken away;

Fig. 2 is a reduced scale horizontal section taken substantially along the line 22 in Fig. 1, with parts broken away;

Fig. 3 is a view similar to Fig. 1 and illustrating a modified form of the invention, and

Fig. 4 is a view similar to Fig. 2 and taken substantially along the line 44 in Fig. 3.

As a preferred or exemplary embodiment of the in- Patented Aug. 28, 1956 stant invention the drawings illustrate a rotary transfer mechanism for a can closing machine of the character disclosed in United States Patent 2,039,338 issued May 5, 1936 to R. E. J. .Nordquist et al. on Vacuum Closing Machine. In such a machine filled cans are passed, by way of a rotary transfer mechanism, from the outside atmosphere into a vacuumized compartment for sealing and are then passed, by way of another rotary transfer mechanism, from the vacuumized compartment back into the atmosphere for shipment and storage.

In the preferred form of the invention shown in Figs. 1 and 2, the rotary transfer mechanism comprises a rotary transfer valve 11 disposed adjacent a can transfer opening 12 in a housing 13 enclosing a conventional pres surized closing compartment 14, preferably containing a gas under pressure, into which filled cans A preferably with their top closures loosely applied are passed for final sealing in the usual manner. For the purposes of this specification the word pressurized is intended to cover a gas under positive pressure or a vacuum which is negative pressure. The valve 11 preferably is mounted on a ball bearing 16 and a thrust bearing 17 carried on a stationary upright shaft or support 18 secured to a frame 19 constituting a portion of the main frame of the closing machine.

The valve 11 is rotated in a clockwise direction as viewed in Fig. 2 by a ring gear 21 which preferably is an itnegral part of the valve and which meshes with a driving pinion 22 carried on a vertical shaft 23 journaled in a bearing 24 formed in the frame 19. The shaft 23 is driven in any suitable manner in time with the other parts of the closing machine. Pockets 26 are formed in the valve 11 at spaced intervals around its periphery for carrying the cans A.

The transfer valve 11 preferably has a tapered outer face and rotates in a correspondingly tapered cylindrical valve seat 29 formed in a curved or cylindrical wall section 31, which seat is open at its top and bottom ends. This wall section 31 constitutes a portion of a housing for the valve and preferably extends out from the closing compartment housing 13 on each side of the can transfer opening 12. An inlet opening 34 formed in the wall section 31 provides for feeding the filled cans A in any suitable manner into the valve pockets 26 for transfer into the gassing compartment 14. It is these

openings

12 and 34 that are sealed by the valve 11 to prevent outside free or atmospheric air from entering the pressurized closing compartment 14 and reducing the vacuum or diluting the gas contained therein.

As a filled can A, preferably carrying a loose top closure, is received in a valve pocket 26 for transfer into the gassing compartment 14, and is carried around toward the can transfer opening 12, the pocket 26 and the head space within the can preferably are successively prevacuumized and pregassed to eliminate as much as possible of the free air which enters the pocket while it is exposed to the outside atmosphere while at the inlet opening 34 during the reception of the can A.

Prevacuumizing of the pockets 26 preferably is effected by a pair of

spaced ports

36, 37 formed in the valve seat wall section 31. These ports are connected by

pipes

38, 39 to any suitable source of vacuum. As the pockets 26 pass the

ports

36, 37 the air is exhausted from them and the cans therein.

Where sealing of the cans A in the compartment 14 is to be effected under vacuum, the desired vacuum condition is maintained in the compartment and usually a lower vacuum is maintained in the

pipes

38, 39 to only partially exhaust the air from the pockets 26. Under these conditions no gas is used. Where the cans are to be sealed in a gaseous medium, for example carbon dioxide or other suitable gas, the compartment 14 contains such a gas, usually under a predetermined pressure.

Under such latter condition of sealing the cans in a gaseous medium, the cans A are usually prevacuumized in their valve pockets 26 as explained above and are also pregassed while still in their pockets before being delivered into the gassing compartment 14. This pregassing of the pockets 26 as the valve rotates is effected by a port 41 formed in the valve seat wall section 31 and located between the vacuum port 37 and the can transfer opening 12 in the housing 13. A pipe 42 connects the gassing port 41 to a suitable source of gas under pressure.

When a can A is prevacuumized and pregassed and advanced to a position opposite the can transfer opening 12 in the housing 13, it is pushed out of its pocket 26 and into the compartment 14 for sealing. This is effected by a discharge finger 44. There is one of these fingers 44 in each valve pocket 26 and they are mounted on individual upright rocker shafts 45 carried in upper and lower bearings 46 formed in the valve 11.

Each of the rocker shafts 45 extends above the valve 11 and carries a cam arm 47 having on its outer end a cam roller 48. All of the cam rollers 48 operate in a cam groove 49 formed in a stationary cover plate 51 which is disposed over the top end of the valve 11 and which at its outer edge is bolted to the top edge of the valve seat wall section 31. As the valve 11 rotates, the cam rollers 48 traverse the cam groove 49 which is shaped to rock the rocker shafts 45 and discharge fingers 44 at the proper time.

Provision is made for the free rotation of the valve 11 relative to its seat 29 without leakage of free or atmospheric air past the valve so that this air is prevented from entering the valve pockets 26 during their travel from the can inlet opening 34 to the compartment entrance opening 12. To effect this free rotation of the valve 11, the thrust bearing 17 is utilized to support the full load of the valve and a slight annular clearance space 53 is provided between the outer face of the valve and the cylindrical valve seat 29. This space 53 is pressurized with a fluid medium to keep it free of air. For this purpose the top and bottom areas of the valve 11 at the opposite ends of the valve and the open ended cylindrical valve seat 29 are fully enclosed and pressurized.

Above the valve 11, the cover plate 51 seals off the space within the valve seat 29, the cover plate being recessed to provide a closed chamber 55 disposed above the valve and in complete communication with the upper end of the annular clearance space 53 between the valve and its seat. The cover plate 51 is provided with a port 56 which is connected by a pipe 57 and T-fitting 58 to two pipes 59, 69 respectively leading from a source of vacuum and a source of gas under pressure. Shut Off valves 61, 62 in the respective pipes 59, are provided to create a vacuum or introduce gas into the chamber 55 as required.

In a similar manner the bottom end of the transfer valve 11 is fully enclosed by a surrounding skirt 63 which extends down from the housing 13 and the valve seat Wall section 31 and fits against a flat web section 64 of the machine frame 19. The skirt 63 and web section 64 set off a closed chamber 65 which is in complete communication with the lower end of the annular clearance space 53, and in which chamber the bottom end of the valve 11 and the valve seat 29, as well as the support shaft 18, thrust bearing 17, and valve actuating or driving pinion 22 are disposed. A port 66 in the web section 64 provides for vacuumizing or gassing the chamber 65 as required. This port is connected by a pipe 67 and T-fitting 68 to two

pipes

69, 70 provided with shut off

valves

71, 72 and leading respectively from a source of vacuum and a source of gas.

Hence if the cans A are to be sealed under vacuum in the sealing compartment 14, the

chambers

55, 65 above and below the transfer valve 11 are vacuumized through A the opening of the shut off valves 61, 71 in vacuum pipes 59, 69 and thus a vacuum is created in the

chambers

55, 65. Since these

chambers

55, 65 communicate respectively with the upper and lower ends of the annular clearance space 53 between the transfer valve 11 and its cylindrical seat 29, any free air that seeps into this space through the can inlet opening 34 is rapidly exhausted through the

chambers

55, 65. Hence this free air is prevented from leaking into the valve pockets 26 while they are being prevacuumized during their rotation toward the can transfer or inlet opening 12 intothe pressurized closing compartment 14.

If the cans A are to be sealed under gas pressure in the sealing compartment 14, the

chambers

55, 65 may be similarly pressurized with gas if desired, through the closing of the vacuum shut off valves 61, 71 and the opening of the gas shut off valves 62, 72. This admits gas under pressure into the

chambers

55, 65 and thereby fills the annular space 53 between the transfer valve 11 and its seat 29 with gas which excludes outside free air from the space.

Hence in either case, the outside free air is prevented from leaking through the space 53 between the transfer valve 11 and its seat 29 into the can pockets 26 of the valve with the result that very little if any free air is introduced into the sealing compartment 14 with the cans A as they are delivered thereto for sealing. At the same time the annular space 53 may be of such proportions as to permit free rotation of the transfer valve 11 with the result that less friction induced wear is incurred by the valve and its seat and less power is needed to rotate the valve. This greatly increases the efficiency of the machine and maintenance of a vacuum or gas pressure condition in the can sealing chamber 14.

As a modified form of the invention, Figs. 3 and 4 of the drawings illustrate a form of transfer valve 11 in which radial spider webs 81 (Fig. 4) are utilized to provide spaced vertical channels 82 through the central portion of the valve. These channels 82 extend from one end of the valve to the other and effect continuous and uninterrupted communication between the upper chamber 55 and the lower chamber 65 so that only one of these chambers need be connected with sources of vacuum and gas. In Fig. 3 the drawing shows the web section 64 having a port 83 which is connected by a pipe 84 and T-fitting 85 to two

pipes

86, 87 having shut oif

valves

88, 89 and leading respectively to a source of vacuum and a source of gas. Hence the one port 83 serves both

chambers

55, 65 with the same result as mentioned above in connection with the preferred form of the invention. If desired the port 83 may be provided in the cover plate 51 instead of in the frame web section 64.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

1. In a transfer mechanism for containers, the combination of a housing enclosing a pressurized compartment and having a can transfer opening therein, a rotatable transfer valve disposed adjacent said transfer opening for sealing the same, said valve having peripherally disposed spaced pockets for carrying containers to said opening for delivery therethrough into said compartment, a valve seat surrounding the periphery of said valve and said transfer opening to provide an annular clearance space between said valve and seat, a closed pressurized chamber adjacent each end of said valve, said chambers communicating with opposite ends of said annular clearance space, and means for pressurizing said chambers to in turn pressurize said communicating clearance space between said valve and its seat to protect said valve pockets against leakage of atmospheric air thereinto through said space.

2. In a transfer mechanism for containers, the combination of a housing enclosing a pressurized compartment and having a can transfer opening therein, a rotatable transfer valve disposed adjacent said transfer opening for sealing the same, said valve having peripherally disposed spaced pockets for carrying containers to said opening for delivery therethrough into said compartment, a valve seat surrounding the periphery of said valve and said transfer opening to provide an annular clearance space between said valve and seat, a closed pressurized chamber adjacent each end of said valve, said chambers communicating with opposite ends of said annular clearance space, and means connecting said chambers with a source of vacuum and a source of gas under pressure for pressurizing said chambers to in turn pressurize said communicating clearance space between said valve and its seat to protect said valve pockets against leakage of atmospheric air thereinto through said space.

3. In a transfer mechanism for containers, the combination of a housing enclosing a pressurized compartment and having a can transfer opening therein, a rotatable transfer valve disposed adjacent said transfer opening for sealing the same, said valve having an enclosing housing and peripherally disposed spaced pockets for carrying containers to said opening for delivery therethrough into said compartment, a cylindrical valve seat on a wall of said valve housing surrounding the periphery of said valve and disposed in spaced relation thereto and also surrounding said transfer opening to provide an annular clearance space between said valve and seat, said clearance space being open at its opposite ends, means for sealing off the opposite ends of said valve housing to provide a closed chamber at each end of said valve, said chambers respectively being in full communication with opposite ends of said annular clearance space between said valve and said seat, and means for pressurizing said chambers to in turn pressurize therethrough said communicating clearance space to protect said valve pockets against ingress of atmospheric air from said space.

4. In a transfer mechanism for containers, the combination of a housing enclosing a pressurized compartment and having a can transfer opening therein, a r0- tatable transfer valve disposed adjacent said transfer opening for sealing the same, said valve having an enclosing housing and peripherally disposed spaced pockets for carrying containers to said opening for delivery therethrough into said compartment, a cylindrical valve seat on said valve housing surrounding said valve and said transfer opening to provide an annular clearance space between said valve and seat and open at its opposite ends, a closed pressurized chamber adjacent each end of said valve, said chambers being independent of each other and respectively in communication with the opposite open ends of said clearance space, and means for pressurizing said chambers independently of each other to in turn pressurize therethrough from opposite ends of said valve the adjoining ends of said clearance space to protect said space and said valve pockets against leakage thereinto of atmospheric air.

5. In a transfer mechanism for containers, the combination of a housing enclosing a pressurized compartment and having a can transfer opening therein, a rotatable transfer valve disposed adjacent said transfer opening for sealing the same, said valve having an enclosing housing and peripherally disposed spaced pockets for carrying containers to said opening for delivery therethrough into said compartment, said valve further having an open channel extending therethrough from one end to the other, a valve seat on said valve housing surrounding said valve and said transfer opening to provide an open ended annular clearance space between said valve and seat, a closed pressurized chamber disposed adjacent each end of said valve, said chambers respectively communicating with opposite ends of said clearance space and valve channel for communicably connecting said chambers, and means connected with one of said closed chambers for pressurizing both of said chambers through said valve channel to in turn pressurize said clearance space, thereby protecting said space and said valve pockets against ingress of atmospheric air.

6. In a transfer mechanism for containers, the combination of a housing enclosing a pressurized compartment and having a can transfer opening therein, a rotatable transfer valve disposed adjacent said transfer opening for sealing the same, said valve having peripherally disposed spaced pockets for carrying containers to said opening for delivery therethrough into said compartment, a cylindrical housing wall section open at its opposite ends and surrounding said valve and said transfer opening, said wall section having a cylindrical seat for said valve and providing an open-ended annular clearance space therebetween, spaced means connected to said wall section and communicating with said valve seat at spaced localities remote from said transfer opening respectively for successively prevacuumizing and pregassing said valve pockets, closure means connected to the opposite open ends of said wall section for sealing said wall section and for providing a closed chamber adjacent each end of said valve, said chambers being respectively communicably connected with the open ends of said clearance space, and means for pressurizing said chambers to in turn pressurize therethrough said clearance space, thereby protecting said space and said valvepockets against leakage thereinto of atmospheric air.

References Cited in the file of this patent UNITED STATES PATENTS