TRANSFER ASSEMBLY FOR USE WITH CONTAINER PRINTING MACHINES
United States Patent 3567043
A transfer assembly for continuously removing printed cans from the mandrels of a container printing machine and placing the cans on a drying oven conveyor, the transfer assembly including a plurality of pneumatically actuated can holders mounted on an endless conveyor and laterally reciprocable thereon, whereby each can holder is moved laterally in one direction to remove a printed can from a mandrel, and then in the opposite direction to place the can on the drying oven conveyor.
US Patent References:
Vessel handling and finishing device
McNamara et al. - June 1935 - 2004492
Vacuum system for load handling
Carliss - November 1965 - 3219380
Transfer assembly for use with high speed can decorating machines
Brigham et al. - January 1967 - 3300019
Article handling and transfer device
Mooney - February 1967 - 3302803
Vessel handling and finishing device
McNamara et al. - June 1935 - 2004492
Vacuum system for load handling
Carliss - November 1965 - 3219380
Transfer assembly for use with high speed can decorating machines
Brigham et al. - January 1967 - 3300019
Article handling and transfer device
Mooney - February 1967 - 3302803
Inventors:
Sirvet, Enn (Ridgefield, NJ)
Whelan, Edward J. (Hasbrouck Heights, NJ)
Skrypek, John P. (Clifton, NJ)
Whelan, Edward J. (Hasbrouck Heights, NJ)
Skrypek, John P. (Clifton, NJ)
Application Number:
04/750182
Publication Date:
03/02/1971
Filing Date:
08/05/1968
View Patent Images:
Export Citation:
Assignee:
Sun Chemical Corporation (New York, NY)
Primary Class:
Other Classes:
198/610, 101/40, 294/64.100, 198/803.500
International Classes:
B65G47/84; B65G47/34
Field of Search:
302/2 198/20,22,22 (B)/ 198/25 214/1 (B2)/ 214/1 (B3)/ 294/64
Primary Examiner:
Nielsen, Andres H.
Claims:
We claim
1. A transfer assembly for sequentially transferring decorated containers from a mandrel carrier to a drying oven conveyor comprising, a conveyor, pneumatically actuated container holder means mounted on said conveyor, pneumatic manifold means connected to said container holder means, said pneumatic manifold means comprising, a disc, a drive shaft connected to said disc for imparting rotary movement thereto coincident with the movement of the conveyor, a plurality of radially extending passages formed in said disc, a vacuum source being connected to said radial passages, a plurality of transverse passages formed in said disc, each transverse passage communicating with a respective radial passage, a source of fluid pressure being mounted adjacent the rotary disc and being sequentially aligned with each transverse passage as the disc is rotated past the fluid pressure source, whereby when connected to the vacuum source, the container holder means is actuated to remove a decorated container from the mandrel carrier, and when connected to the fluid pressure source the container holder means is actuated to place a decorated container on the drying oven conveyor.
2. A transfer assembly according to claim 1, wherein the container holder means comprises, a plurality of cylindrical housings, each housing having a piston slidably mounted therein, a suction cup secured to one end of the piston and projecting outwardly from one end of the housing, the opposite end of the housing being connected to the pneumatic manifold means, whereby the suction cup is adapted to engage the bottom of the decorated container being removed from the mandrel carrier, and when the housing is connected to the vacuum source the piston is drawn inwardly thereof, and when connected to the fluid pressure source the piston is moved outwardly of the housing.
3. A transfer assembly according to claim 2, wherein bores are formed within the piston communicating with the interior of the suction cup and said opposite end of the housing, whereby, when the housing is connected to the source of vacuum the interior of the suction cup is also placed under vacuum.
4. A transfer assembly according to claim 2, wherein the conveyor comprises an endless sprocket and chain assembly, a plurality of horizontally disposed pins carried by the chain assembly, each housing having a depending pedestal slidably mounted on said pins, a cam follower mounted on each pedestal, said cam follower engaging a stationary cam mounted adjacent the conveyor, whereby upon movement of the conveyor, the cam causes each housing to slide laterally on the conveyor relative to the mandrel carrier and drying oven conveyor.
5. A transfer assembly according to claim 1, wherein the control means, comprises valve means mounted within each transverse passage.
6. A transfer assembly according to claim 5, wherein the valve means comprises a spring-biased spool valve, said valve being normally biased to open position to establish communication between the vacuum source and the container holder means, the spool valve being moved to closed position by the fluid pressure when the transverse passage is aligned with the source of fluid pressure.
7. A transfer assembly according to claim 6, wherein additional radial and transverse passages are formed in the disc adjacent the valve means for establishing communication between the source of fluid pressure and container holder means when the spool valve is moved to closed position.
8. A transfer assembly according to claim 1, wherein the source of fluid pressure includes a nozzle adjustably mounted on a support frame positioned adjacent the rotary disc, the end of the nozzle having antifriction material formed thereon adapted to abut the surface of the rotary disc.
9. A transfer assembly for sequentially transferring decorated containers from a mandrel carrier to a drying oven conveyor comprising, a conveyor, pneumatically actuated container holder means mounted on said conveyor, pneumatic manifold means connected to said container holder means, said pneumatic manifold means being connected to a vacuum source and a source of fluid pressure, and control means operatively connected to said manifold means for selectively establishing communication between the container holder means and the vacuum source and fluid pressure source, said container holder means comprising, a plurality of cylindrical housings, each housing having a piston slidably mounted therein, a suction cup secured to one end of the piston and projecting outwardly from one end of the housing, the opposite end of the housing being connected to the pneumatic manifold means, and bore means formed within the piston communicating with the interior of the suction cup and said opposite end of the housing, whereby the suction cup is adapted to engage the bottom of a decorated container on the mandrel carrier, and when the housing is connected to the vacuum source the interior of the suction cup is also placed under vacuum and the piston is drawn inwardly of the housing to thereby remove the decorated container from the mandrel carrier, and when connected to the fluid pressure source the piston is moved outwardly of the housing for placing the decorated container on the drying oven conveyor.
10. A transfer assembly according to claim 9 wherein the pneumatic manifold means comprises, a disc, a drive shaft connected to said disc for imparting rotary movement thereto coincident with the movement of the conveyor, a plurality of radially extending passages formed in said disc, said radial passages being connected to the vacuum source, a plurality of transverse passages formed in said disc, each transverse passage communicating with a respective radial passage, the source of fluid pressure being mounted adjacent the rotary disc and being sequentially aligned with each transverse passage as the disc is rotated past the fluid pressure source.
11. A transfer assembly according to claim 10 wherein the control means, comprises valve means mounted within each transverse passage.
12. A transfer assembly according to claim 11, wherein the valve means comprises a spring-biased spool valve, said valve being normally biased to open position to establish communication between the vacuum source and the container holder means, the spool valve being moved to closed position by the fluid pressure when the transverse passage is aligned with the source of fluid pressure.
13. A transfer assembly according to claim 12, wherein additional radial and transverse passages are formed in the disc adjacent the valve means for establishing communication between the source of fluid pressure and container holder means when the spool valve is moved to closed position.
14. A transfer assembly according to claim 10, wherein the source of fluid pressure includes a nozzle adjustably mounted on a support frame positioned adjacent the rotary disc, the end of the nozzle having antifriction material formed thereon adapted to abut the surface of the rotary disc.
15. A transfer assembly according to claim 9, wherein the conveyor comprises an endless sprocket and chain assembly, a plurality of horizontally disposed pins carried by the chain assembly, each housing having a depending pedestal slidably mounted on said pins, a cam follower mounted on each pedestal, said cam follower engaging a stationary cam mounted adjacent the conveyor, whereby upon movement of the conveyor, the cam causes each housing to slide laterally on the conveyor relative to the mandrel carrier and drying oven conveyor.
1. A transfer assembly for sequentially transferring decorated containers from a mandrel carrier to a drying oven conveyor comprising, a conveyor, pneumatically actuated container holder means mounted on said conveyor, pneumatic manifold means connected to said container holder means, said pneumatic manifold means comprising, a disc, a drive shaft connected to said disc for imparting rotary movement thereto coincident with the movement of the conveyor, a plurality of radially extending passages formed in said disc, a vacuum source being connected to said radial passages, a plurality of transverse passages formed in said disc, each transverse passage communicating with a respective radial passage, a source of fluid pressure being mounted adjacent the rotary disc and being sequentially aligned with each transverse passage as the disc is rotated past the fluid pressure source, whereby when connected to the vacuum source, the container holder means is actuated to remove a decorated container from the mandrel carrier, and when connected to the fluid pressure source the container holder means is actuated to place a decorated container on the drying oven conveyor.
2. A transfer assembly according to claim 1, wherein the container holder means comprises, a plurality of cylindrical housings, each housing having a piston slidably mounted therein, a suction cup secured to one end of the piston and projecting outwardly from one end of the housing, the opposite end of the housing being connected to the pneumatic manifold means, whereby the suction cup is adapted to engage the bottom of the decorated container being removed from the mandrel carrier, and when the housing is connected to the vacuum source the piston is drawn inwardly thereof, and when connected to the fluid pressure source the piston is moved outwardly of the housing.
3. A transfer assembly according to claim 2, wherein bores are formed within the piston communicating with the interior of the suction cup and said opposite end of the housing, whereby, when the housing is connected to the source of vacuum the interior of the suction cup is also placed under vacuum.
4. A transfer assembly according to claim 2, wherein the conveyor comprises an endless sprocket and chain assembly, a plurality of horizontally disposed pins carried by the chain assembly, each housing having a depending pedestal slidably mounted on said pins, a cam follower mounted on each pedestal, said cam follower engaging a stationary cam mounted adjacent the conveyor, whereby upon movement of the conveyor, the cam causes each housing to slide laterally on the conveyor relative to the mandrel carrier and drying oven conveyor.
5. A transfer assembly according to claim 1, wherein the control means, comprises valve means mounted within each transverse passage.
6. A transfer assembly according to claim 5, wherein the valve means comprises a spring-biased spool valve, said valve being normally biased to open position to establish communication between the vacuum source and the container holder means, the spool valve being moved to closed position by the fluid pressure when the transverse passage is aligned with the source of fluid pressure.
7. A transfer assembly according to claim 6, wherein additional radial and transverse passages are formed in the disc adjacent the valve means for establishing communication between the source of fluid pressure and container holder means when the spool valve is moved to closed position.
8. A transfer assembly according to claim 1, wherein the source of fluid pressure includes a nozzle adjustably mounted on a support frame positioned adjacent the rotary disc, the end of the nozzle having antifriction material formed thereon adapted to abut the surface of the rotary disc.
9. A transfer assembly for sequentially transferring decorated containers from a mandrel carrier to a drying oven conveyor comprising, a conveyor, pneumatically actuated container holder means mounted on said conveyor, pneumatic manifold means connected to said container holder means, said pneumatic manifold means being connected to a vacuum source and a source of fluid pressure, and control means operatively connected to said manifold means for selectively establishing communication between the container holder means and the vacuum source and fluid pressure source, said container holder means comprising, a plurality of cylindrical housings, each housing having a piston slidably mounted therein, a suction cup secured to one end of the piston and projecting outwardly from one end of the housing, the opposite end of the housing being connected to the pneumatic manifold means, and bore means formed within the piston communicating with the interior of the suction cup and said opposite end of the housing, whereby the suction cup is adapted to engage the bottom of a decorated container on the mandrel carrier, and when the housing is connected to the vacuum source the interior of the suction cup is also placed under vacuum and the piston is drawn inwardly of the housing to thereby remove the decorated container from the mandrel carrier, and when connected to the fluid pressure source the piston is moved outwardly of the housing for placing the decorated container on the drying oven conveyor.
10. A transfer assembly according to claim 9 wherein the pneumatic manifold means comprises, a disc, a drive shaft connected to said disc for imparting rotary movement thereto coincident with the movement of the conveyor, a plurality of radially extending passages formed in said disc, said radial passages being connected to the vacuum source, a plurality of transverse passages formed in said disc, each transverse passage communicating with a respective radial passage, the source of fluid pressure being mounted adjacent the rotary disc and being sequentially aligned with each transverse passage as the disc is rotated past the fluid pressure source.
11. A transfer assembly according to claim 10 wherein the control means, comprises valve means mounted within each transverse passage.
12. A transfer assembly according to claim 11, wherein the valve means comprises a spring-biased spool valve, said valve being normally biased to open position to establish communication between the vacuum source and the container holder means, the spool valve being moved to closed position by the fluid pressure when the transverse passage is aligned with the source of fluid pressure.
13. A transfer assembly according to claim 12, wherein additional radial and transverse passages are formed in the disc adjacent the valve means for establishing communication between the source of fluid pressure and container holder means when the spool valve is moved to closed position.
14. A transfer assembly according to claim 10, wherein the source of fluid pressure includes a nozzle adjustably mounted on a support frame positioned adjacent the rotary disc, the end of the nozzle having antifriction material formed thereon adapted to abut the surface of the rotary disc.
15. A transfer assembly according to claim 9, wherein the conveyor comprises an endless sprocket and chain assembly, a plurality of horizontally disposed pins carried by the chain assembly, each housing having a depending pedestal slidably mounted on said pins, a cam follower mounted on each pedestal, said cam follower engaging a stationary cam mounted adjacent the conveyor, whereby upon movement of the conveyor, the cam causes each housing to slide laterally on the conveyor relative to the mandrel carrier and drying oven conveyor.
Description:
BACKGROUND OF THE INVENTION
The transfer assembly of the present invention is adapted to be employed with the continuously rotatable mandrel assembly disclosed in our copending application Ser. No. 739,049 filed Jun. 21, 1968, wherein there is described a plurality of can carrying mandrels constructed and arranged to follow a path parallel to the impression surface of a printing cylinder during the printing cycle, whereby the mandrel assembly may be continuously, rather than intermittently, rotated to thereby increase the number of cans which can be decorated during a given period of time.
Heretofore, container decorating machines, having intermittently rotatable mandrel carriers, have employed intermittently rotatable transfer assemblies for transferring a decorated container from the mandrel carrier to a drying oven conveyor. Thus, when the mandrel carrier is stopped to allow a container to be decorated at the printing station, a preceding decorated container is being simultaneously transferred to the drying oven conveyor.
With the recent development of high-speed decorating machines of the type disclosed in our above-identified copending application, wherein the mandrel carrier is continuously rotated, it is necessary to provide a transfer assembly for continuously, rather than intermittently, transferring decorated cans from the mandrel carrier to the drying oven conveyor.
While transfer assemblies have been developed for use with continuously rotatable mandrel carriers, the particular can holders employed in these transfer assemblies limit the use thereof for transferring coated cans from the drying oven conveyor to the mandrel carrier for transport to the printing stations. In one proposed arrangement, each can holder comprises a pair of cam-actuated, coacting gripper members of jaws which are adapted to grip the dried, coated, outer surface of the can. Obviously, to use such can gripping members for transferring a wet coated or printed can from the mandrel carrier to the drying oven conveyor would result in the smearing or scratching of the can surface.
To overcome the inherent disadvantages of intermittently operating transfer assemblies and continuously operating transfer assemblies provided with gripping jaw-type can holders, the transfer assembly of the present invention has been devised which comprises, essentially, an endless conveyor having a plurality of can holder carriages laterally slidable thereon. Each can holder is in communication with a vacuum/air pressure manifold, whereby each decorated can is drawn from its respective mandrel, carried to the drying oven conveyor and blown thereon. During the transfer of the cans from the mandrel carrier to the oven drying conveyor, the can holders engage the bottom of each can to thereby prevent any smearing or scratching of the outer surface of the can.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic, side elevational view of the transfer assembly of the present invention illustrating its structural relationship to the mandrel carrier and drying oven conveyor;
FIG. 2 is an enlarged, fragmentary side elevational view of the transfer assembly of the present invention, illustrating the endless conveyor and associated vacuum/air pressure manifold;
FIG. 3 is a fragmentary side elevational view of the endless conveyor employed in the transfer assembly of the present invention;
FIG. 4 is a top plan view of the endless conveyor shown in FIG. 2;
FIG. 5 is a view taken along line 5-5 of FIG. 3;
FIG. 6 is a view taken along line 6-6 of FIG. 3;
FIG. 7 is a sectional, end elevational view of the endless conveyor and associated vacuum/air pressure manifold, illustrating their structural relationship to the mandrel carrier and drying oven conveyor;
FIG. 8 is an enlarged, fragmentary, sectional view of a check valve employed in the vacuum/air pressure manifold; and
FIG. 9 is an enlarged sectional view illustrating one of the can holders employed in the transfer assembly of the present invention.
Referring to the drawings and more particularly to FIG. 1, the transfer assembly 1 of the present invention is positioned between a drying oven conveyor 2 and a continuously rotating mandrel carrier assembly 3 of the type disclosed in our aforementioned copending application Ser. No. 739,049, filed Jun. 21, 1968. Undecorated containers 4 are fed down an inclined chute 5 to a worm screw 6 where they are separated and fed to a feed wheel 7. From the feed wheel, each container is deposited on a respective cradle 8 formed on the peripheral edge of a rotatable disc 9, each of the cradles being aligned with a respective mandrel 10 (FIG. 7) mounted on a carrier 11. As described in our copending application, each undecorated container is mechanically wiped from its cradle onto the outer end portion of a respective mandrel whereupon a vacuum source draws the container completely onto the mandrel. The container carrying mandrels, being rotated in a clockwise direction, as indicated by the arrow in FIG. 1, then approach the decorating cycle where the containers are sequentially coated or printed by the cylinder 12 of a conventional printing machine 13. During this portion of the operation, each container carrying mandrel is caused to follow a path parallel to the surface of the impression blanket of the cylinder 12, while the container is being pressed into engagement with the impression blanket.
The continued rotation of the mandrel carrier brings the decorated container to a transfer point adjacent the transfer assembly 1 whereupon the decorated can is transferred thereto and conveyed to a position adjacent the drying oven conveyor 2 for transfer thereto.
Referring to FIGS. 3, 4 and 7, the transfer assembly 1 comprises a pair of spaced, longitudinally extending frame members 14 and 15 having shafts 16 and 17 extending transversely thereto and journaled within each end portion of the frame members. Shaft 16 has a pair of idler sprocket wheels 18 journaled on each end thereof through suitable bearings 19 (FIG. 5), and shaft 17 has a pair of drive sprockets 20 keyed thereon as at 21 (FIG. 6), power being transmitted to drive shaft 17 through a transmission belt 22 (FIG. 2) extending between a drive pulley 23, secured to the shaft of a motor 24, and a driven pulley 25 secured to the end of shaft 17. An endless chain conveyor 26 extends between each drive sprocket 20 and its associated idler sprocket 18, and as will be seen in FIGS. 3 and 7, certain of the chain links in one of the conveyors have pins 27 extending transversely to a corresponding link in the opposite conveyor. Can holder assemblies or carriages 28 are mounted on the pins 27 and are laterally slidable thereon relative to the conveyor chains 26 through a cam follower 29, connected to each can holder assembly, and positioned within a suitably configured groove in cam plates 30 and 31 (FIG. 7) secured to the frame members 14 and 15 by bolts 32 (FIG. 7). Each of the cam plates 30 and 31 extend longitudinally along the upper and lower runs, respectively, of the chain conveyors 26, the ends of the cam plates terminating adjacent grooved wheels 33 and 34 mounted on shafts 16 and 17, respectively; wheel 33 being rotatably mounted on shaft 16 through bearings 35 (FIG. 5) and wheel 34 being keyed as at 36 to shaft 17. As will be seen in FIGS. 4, 5 and 6, the grooved wheels are mounted on their respective shafts in such a position that the grooves are aligned with the grooves in the cam plates 30 and 31 to thereby provide a continuous track for the cam followers 29 for their travel along the upper and lower runs of the chain conveyors and around the sprocket wheels 18 and 20.
In the operation of the transfer assembly, thus far described, it will be readily understood that upon rotation of the drive shaft 17 the endless chain conveyors will carry the can holders 28 around an endless path, while the cam followers 29, riding in the cam grooves, will cause the can holders to slide laterally on pins 27 to thereby move each can holder into proximity to the mandrel 10 for the removal of a decorated can therefrom, and to the drying oven conveyor 2 for the depositing of a decorated can thereon.
In order that each can holder 28 will be aligned with a respective mandrel 10 to facilitate the transfer of a decorated can from the mandrel, the upper run of each endless chain conveyor 26 is caused to follow an arcuate path concentric to the path of the mandrel carrier 11. As will be seen in FIGS. 3 and 7, this arcuate path is defined by plates 37 and 38 bolted as at 39 to frame members 14 and 15, respectively. The upper edges of plates 37 and 38 are arcuately configured and cooperate with similarly configured lower edges of plates 40 and 41, spaced above plates 37 and 38 and secured thereto by gusset plates 42.
The lower run of each endless chain conveyor 26 is guided in a straight path by a track formed by the lower edges of plates 37 and 38 and the upper edges of plates 43 and 44 spaced therefrom and secured to plates 37 and 38 by gusset plates 45.
Referring to FIGS. 7 and 9, each can holder 28 comprises a piston 46 slidably mounted within a cylindrical housing 47. A suction cup 48 is secured to the end of the piston which projects outwardly from the cylindrical housing, the cup communicating with one end of a longitudinal bore 49 formed in the piston, the opposite end of the bore communicating with a transverse bore 50 which, in turn, communicates with an annular chamber 51 defined by the outer peripheral wall of piston 46 and the inner peripheral wall of a bearing sleeve 52 mounted within the cylindrical housing. Annular chamber 51 is also in communication with the atmosphere through port 53 extending through the wall of housing 47. The inward and outward travel of piston 46 relative to the cylindrical housing is limited by flange 54, integrally formed on the piston, and engageable with a shoulder 55 formed in the medial portion of the cylindrical housing and with a collar 56 secured to the outer end of the housing. The inner end portion of the housing is formed with a chamber 57 having a smaller diameter than chamber 51 for receiving the inner end portion of piston 46, which is slidably received within a bearing sleeve 58 mounted within the housing. As will be seen in FIG. 7, bearing sleeve 58 maintains the outer peripheral wall of the piston 46 spaced from the inner peripheral wall of the chamber 57 to thereby provide a clearance 59 so that chamber 57 will be in communication with transverse bore 50 when the piston has been moved to its inward position. The inner end wall of housing 47 is provided with an aperture 60 for receiving the end of a tubular conduit 61 through which chamber 57 can be either pressurized or placed under vacuum, to be described more fully hereinafter. The wall of the housing 47 is also provided with a spring-biased check valve 62 which is adapted to open when chamber 57 is pressurized and closed when chamber 57 is under vacuum. To complete the structure of the can holders, a depending pedestal 63 is integrally formed on each housing 28, the lower end of the pedestal having a hub portion 64 slidably mounted on the pins 27, the cam followers 29 being connected to the hub portions.
In the operation of the can holders thus far described, it will be readily apparent that when chamber 57 is pressurized, piston 46 will be moved outwardly of housing 47 and when under vacuum the piston will be drawn inwardly of the housing. The placing of chamber 57 under pressure and vacuum is determined by the position of each can holder 28 relative to the mandrel carrier 11 and drying oven conveyor 2. As will be seen in FIG. 7, when a can carrying mandrel 10 passes an air pressure nozzle 65 the decorated can is blown from the mandrel toward the can holder suction cup 48 which is aligned with the mandrel. As the can is being blown from the mandrel, chamber 57 is maintained under vacuum and since bores 49 and 50 communicate with chamber 57, the interior of the suction cup 48 is also placed under vacuum whereby the can is drawn completely off the mandrel and held by the suction cup 48 engaging the bottom of the can. The can carrying holder 28 is then conveyed to a conventional chain-pin-type drying oven conveyor 2 whereupon chamber 57 is pressurized to move the piston outwardly of the housing to thereby deposit the can on a pin 66 on the conveyor. As will be seen in FIG. 9, when piston 46 has been moved to its extended position, bores 49 and 50 are in communication with chamber 51 which is under atmospheric pressure through port 53; thus, the suction cup loses its holding force on the bottom of the can since it too will be under atmospheric pressure.
Referring to FIGS. 2 and 7, the assembly for placing chamber 57 of each can holder under pressure and vacuum comprises, a disc-type manifold 67 secured to a rotatable shaft 68 journaled in the upper end of a support frame 69 through bearings 70. Rotation is imparted to shaft 68 through a drive belt 71 connected between a drive pulley 72 secured to the shaft of motor 24, and a driven pulley 73 secured to the shaft 68. Shaft 68 has an axially extending bore 74 formed therein having one end communicating with a fitting 75, adapted to be connected to a vacuum source, the opposite end of the bore communicating with a centrally disposed chamber 76 formed in the manifold disc. A plurality of radially extending passages 77 are also formed in manifold disc 67, each passage having one end communicating with chamber 76 and the opposite end communicating with a pipe 78. One end of each pipe is threaded into the outer peripheral wall of the manifold and the opposite end is connected to the tubular conduit 61. Each radial passage 77 has an axial or transverse passage 79 extending therethrough which contains a spring-biased spool valve 80. Another transverse passage 81 is formed in the manifold disc which has one end communicating with the portion of radial passage 77 adjacent the end of the pipe 78 and the opposite end communicating with a radial passage 82 which has one end communicating with transverse passage 79 and the opposite end closed by a condensate drain plug 83.
Each of the spool valves 80 is biased to the right, as shown in FIG. 7, against a ring member 84 secured to the face of the manifold disc, and having a plurality of circumferentially spaced apertures 85 therein. Each of the apertures 85 is aligned with a respective spool valve 80 for establishing communication between the valve and an air pressure nozzle 86. As will be seen in FIG. 2, the nozzle 86 is carried by an arcuate arm 87 which is secured to the support 69 by bolts 88 extending through slots 89 formed in the end portions of the arm whereby the nozzle is adjustably mounted on the support 69 to thereby maintain the nozzle 86 in alignment with the apertures 85. As will be seen in FIG. 7, one end of the nozzle 86 is connected to air pressure conduit 90 and the opposite end of the nozzle is provided with an antifriction material 91 against which the ring member 84 slides during rotation of the manifold disc 67.
From the above description, it will be readily apparent that chamber 57 of each can holder will be placed under vacuum when its respective spool valve 80 is biased to the right, to open position as shown in FIG. 7, the vacuum being drawn through conduit 61, pipe 78, valve 80, passage 77, and bore 74. The chamber 57 is placed under pressure when the manifold disc 67 has been rotated to position the spool valve 80 adjacent the air pressure nozzle 86; whereupon the air pressure forces the spool valve 80 to the left, or closed position, as shown in FIG. 8, to cut off the vacuum to pipe 78. While the valve is maintained in this position, pressurized air flows through aperture 85, passage 81 and pipe 78 to the chamber 57 through conduit 61.
The operation of the transfer assembly of the present invention will be best understood by referring to FIG. 7 wherein it will be seen that when the mandrel carrier 11 moves past the air pressure nozzle 65, each decorated can 4 is sequentially blown from the mandrel 10 toward one of the suction cups 48 carried by a can holder 28. The bottom of the can is held against the suction cup through vacuum which communicates with the cup through bores 49 and 50 in the piston 46, clearance 59, chamber 57, conduit 61, pipe 78, open spool valve 80, passage 77, chamber 76 in the disc manifold and bore 74 in rotary shaft 68. With each can thus held on a respective holder, the endless chain conveyor 26 moves the can carrying holders 28 around to the oven drying conveyor 2. During the travel of the chain conveyor, the cam plates 30 and 31 cause the can holders to slide laterally on the pins 27 to facilitate the removal of the decorated can from the mandrel 10 and the depositing of the can on the pin 66 of the oven drying conveyor 2.
The chain conveyor 26 and manifold disc 67 are simultaneously rotated so that when each can carrying holder 28 is positioned adjacent a pin 66 on the oven drying conveyor 2, the spool valve 80 will be aligned with the air pressure nozzle 86, whereby the spool valve is moved to cut off the vacuum to the holder, thereby allowing pressurized air to flow to the can holder 28 to force the piston 46 outwardly therefrom whereby the decorated can is pushed onto the pin 66 of the oven drying conveyor. When the manifold disc 67 moves past the nozzle 86, the spool valve 80 will be spring biased to open position to thereby establish communication between the vacuum source and the can holder 28 which is carried by the endless chain conveyor 26 back to the mandrel carrier 11 to receive another decorated can therefrom; whereupon the cycle is repeated.
Since the transfer assembly of the present invention is adapted to be used with a continuous container printing machine, it will be understood by those skilled in the art that the can holder conveyor and associated manifold disc are continuously rotated and their structural relationship between the mandrel carrier and oven drying conveyor is such that when a decorated can is being transferred from a mandrel to a can holder, another can is being simultaneously transferred from a holder to the oven drying conveyor.
The transfer assembly of the present invention is adapted to be employed with the continuously rotatable mandrel assembly disclosed in our copending application Ser. No. 739,049 filed Jun. 21, 1968, wherein there is described a plurality of can carrying mandrels constructed and arranged to follow a path parallel to the impression surface of a printing cylinder during the printing cycle, whereby the mandrel assembly may be continuously, rather than intermittently, rotated to thereby increase the number of cans which can be decorated during a given period of time.
Heretofore, container decorating machines, having intermittently rotatable mandrel carriers, have employed intermittently rotatable transfer assemblies for transferring a decorated container from the mandrel carrier to a drying oven conveyor. Thus, when the mandrel carrier is stopped to allow a container to be decorated at the printing station, a preceding decorated container is being simultaneously transferred to the drying oven conveyor.
With the recent development of high-speed decorating machines of the type disclosed in our above-identified copending application, wherein the mandrel carrier is continuously rotated, it is necessary to provide a transfer assembly for continuously, rather than intermittently, transferring decorated cans from the mandrel carrier to the drying oven conveyor.
While transfer assemblies have been developed for use with continuously rotatable mandrel carriers, the particular can holders employed in these transfer assemblies limit the use thereof for transferring coated cans from the drying oven conveyor to the mandrel carrier for transport to the printing stations. In one proposed arrangement, each can holder comprises a pair of cam-actuated, coacting gripper members of jaws which are adapted to grip the dried, coated, outer surface of the can. Obviously, to use such can gripping members for transferring a wet coated or printed can from the mandrel carrier to the drying oven conveyor would result in the smearing or scratching of the can surface.
To overcome the inherent disadvantages of intermittently operating transfer assemblies and continuously operating transfer assemblies provided with gripping jaw-type can holders, the transfer assembly of the present invention has been devised which comprises, essentially, an endless conveyor having a plurality of can holder carriages laterally slidable thereon. Each can holder is in communication with a vacuum/air pressure manifold, whereby each decorated can is drawn from its respective mandrel, carried to the drying oven conveyor and blown thereon. During the transfer of the cans from the mandrel carrier to the oven drying conveyor, the can holders engage the bottom of each can to thereby prevent any smearing or scratching of the outer surface of the can.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic, side elevational view of the transfer assembly of the present invention illustrating its structural relationship to the mandrel carrier and drying oven conveyor;
FIG. 2 is an enlarged, fragmentary side elevational view of the transfer assembly of the present invention, illustrating the endless conveyor and associated vacuum/air pressure manifold;
FIG. 3 is a fragmentary side elevational view of the endless conveyor employed in the transfer assembly of the present invention;
FIG. 4 is a top plan view of the endless conveyor shown in FIG. 2;
FIG. 5 is a view taken along line 5-5 of FIG. 3;
FIG. 6 is a view taken along line 6-6 of FIG. 3;
FIG. 7 is a sectional, end elevational view of the endless conveyor and associated vacuum/air pressure manifold, illustrating their structural relationship to the mandrel carrier and drying oven conveyor;
FIG. 8 is an enlarged, fragmentary, sectional view of a check valve employed in the vacuum/air pressure manifold; and
FIG. 9 is an enlarged sectional view illustrating one of the can holders employed in the transfer assembly of the present invention.
Referring to the drawings and more particularly to FIG. 1, the transfer assembly 1 of the present invention is positioned between a drying oven conveyor 2 and a continuously rotating mandrel carrier assembly 3 of the type disclosed in our aforementioned copending application Ser. No. 739,049, filed Jun. 21, 1968. Undecorated containers 4 are fed down an inclined chute 5 to a worm screw 6 where they are separated and fed to a feed wheel 7. From the feed wheel, each container is deposited on a respective cradle 8 formed on the peripheral edge of a rotatable disc 9, each of the cradles being aligned with a respective mandrel 10 (FIG. 7) mounted on a carrier 11. As described in our copending application, each undecorated container is mechanically wiped from its cradle onto the outer end portion of a respective mandrel whereupon a vacuum source draws the container completely onto the mandrel. The container carrying mandrels, being rotated in a clockwise direction, as indicated by the arrow in FIG. 1, then approach the decorating cycle where the containers are sequentially coated or printed by the cylinder 12 of a conventional printing machine 13. During this portion of the operation, each container carrying mandrel is caused to follow a path parallel to the surface of the impression blanket of the cylinder 12, while the container is being pressed into engagement with the impression blanket.
The continued rotation of the mandrel carrier brings the decorated container to a transfer point adjacent the transfer assembly 1 whereupon the decorated can is transferred thereto and conveyed to a position adjacent the drying oven conveyor 2 for transfer thereto.
Referring to FIGS. 3, 4 and 7, the transfer assembly 1 comprises a pair of spaced, longitudinally extending frame members 14 and 15 having shafts 16 and 17 extending transversely thereto and journaled within each end portion of the frame members. Shaft 16 has a pair of idler sprocket wheels 18 journaled on each end thereof through suitable bearings 19 (FIG. 5), and shaft 17 has a pair of drive sprockets 20 keyed thereon as at 21 (FIG. 6), power being transmitted to drive shaft 17 through a transmission belt 22 (FIG. 2) extending between a drive pulley 23, secured to the shaft of a motor 24, and a driven pulley 25 secured to the end of shaft 17. An endless chain conveyor 26 extends between each drive sprocket 20 and its associated idler sprocket 18, and as will be seen in FIGS. 3 and 7, certain of the chain links in one of the conveyors have pins 27 extending transversely to a corresponding link in the opposite conveyor. Can holder assemblies or carriages 28 are mounted on the pins 27 and are laterally slidable thereon relative to the conveyor chains 26 through a cam follower 29, connected to each can holder assembly, and positioned within a suitably configured groove in cam plates 30 and 31 (FIG. 7) secured to the frame members 14 and 15 by bolts 32 (FIG. 7). Each of the cam plates 30 and 31 extend longitudinally along the upper and lower runs, respectively, of the chain conveyors 26, the ends of the cam plates terminating adjacent grooved wheels 33 and 34 mounted on shafts 16 and 17, respectively; wheel 33 being rotatably mounted on shaft 16 through bearings 35 (FIG. 5) and wheel 34 being keyed as at 36 to shaft 17. As will be seen in FIGS. 4, 5 and 6, the grooved wheels are mounted on their respective shafts in such a position that the grooves are aligned with the grooves in the cam plates 30 and 31 to thereby provide a continuous track for the cam followers 29 for their travel along the upper and lower runs of the chain conveyors and around the sprocket wheels 18 and 20.
In the operation of the transfer assembly, thus far described, it will be readily understood that upon rotation of the drive shaft 17 the endless chain conveyors will carry the can holders 28 around an endless path, while the cam followers 29, riding in the cam grooves, will cause the can holders to slide laterally on pins 27 to thereby move each can holder into proximity to the mandrel 10 for the removal of a decorated can therefrom, and to the drying oven conveyor 2 for the depositing of a decorated can thereon.
In order that each can holder 28 will be aligned with a respective mandrel 10 to facilitate the transfer of a decorated can from the mandrel, the upper run of each endless chain conveyor 26 is caused to follow an arcuate path concentric to the path of the mandrel carrier 11. As will be seen in FIGS. 3 and 7, this arcuate path is defined by plates 37 and 38 bolted as at 39 to frame members 14 and 15, respectively. The upper edges of plates 37 and 38 are arcuately configured and cooperate with similarly configured lower edges of plates 40 and 41, spaced above plates 37 and 38 and secured thereto by gusset plates 42.
The lower run of each endless chain conveyor 26 is guided in a straight path by a track formed by the lower edges of plates 37 and 38 and the upper edges of plates 43 and 44 spaced therefrom and secured to plates 37 and 38 by gusset plates 45.
Referring to FIGS. 7 and 9, each can holder 28 comprises a piston 46 slidably mounted within a cylindrical housing 47. A suction cup 48 is secured to the end of the piston which projects outwardly from the cylindrical housing, the cup communicating with one end of a longitudinal bore 49 formed in the piston, the opposite end of the bore communicating with a transverse bore 50 which, in turn, communicates with an annular chamber 51 defined by the outer peripheral wall of piston 46 and the inner peripheral wall of a bearing sleeve 52 mounted within the cylindrical housing. Annular chamber 51 is also in communication with the atmosphere through port 53 extending through the wall of housing 47. The inward and outward travel of piston 46 relative to the cylindrical housing is limited by flange 54, integrally formed on the piston, and engageable with a shoulder 55 formed in the medial portion of the cylindrical housing and with a collar 56 secured to the outer end of the housing. The inner end portion of the housing is formed with a chamber 57 having a smaller diameter than chamber 51 for receiving the inner end portion of piston 46, which is slidably received within a bearing sleeve 58 mounted within the housing. As will be seen in FIG. 7, bearing sleeve 58 maintains the outer peripheral wall of the piston 46 spaced from the inner peripheral wall of the chamber 57 to thereby provide a clearance 59 so that chamber 57 will be in communication with transverse bore 50 when the piston has been moved to its inward position. The inner end wall of housing 47 is provided with an aperture 60 for receiving the end of a tubular conduit 61 through which chamber 57 can be either pressurized or placed under vacuum, to be described more fully hereinafter. The wall of the housing 47 is also provided with a spring-biased check valve 62 which is adapted to open when chamber 57 is pressurized and closed when chamber 57 is under vacuum. To complete the structure of the can holders, a depending pedestal 63 is integrally formed on each housing 28, the lower end of the pedestal having a hub portion 64 slidably mounted on the pins 27, the cam followers 29 being connected to the hub portions.
In the operation of the can holders thus far described, it will be readily apparent that when chamber 57 is pressurized, piston 46 will be moved outwardly of housing 47 and when under vacuum the piston will be drawn inwardly of the housing. The placing of chamber 57 under pressure and vacuum is determined by the position of each can holder 28 relative to the mandrel carrier 11 and drying oven conveyor 2. As will be seen in FIG. 7, when a can carrying mandrel 10 passes an air pressure nozzle 65 the decorated can is blown from the mandrel toward the can holder suction cup 48 which is aligned with the mandrel. As the can is being blown from the mandrel, chamber 57 is maintained under vacuum and since bores 49 and 50 communicate with chamber 57, the interior of the suction cup 48 is also placed under vacuum whereby the can is drawn completely off the mandrel and held by the suction cup 48 engaging the bottom of the can. The can carrying holder 28 is then conveyed to a conventional chain-pin-type drying oven conveyor 2 whereupon chamber 57 is pressurized to move the piston outwardly of the housing to thereby deposit the can on a pin 66 on the conveyor. As will be seen in FIG. 9, when piston 46 has been moved to its extended position, bores 49 and 50 are in communication with chamber 51 which is under atmospheric pressure through port 53; thus, the suction cup loses its holding force on the bottom of the can since it too will be under atmospheric pressure.
Referring to FIGS. 2 and 7, the assembly for placing chamber 57 of each can holder under pressure and vacuum comprises, a disc-type manifold 67 secured to a rotatable shaft 68 journaled in the upper end of a support frame 69 through bearings 70. Rotation is imparted to shaft 68 through a drive belt 71 connected between a drive pulley 72 secured to the shaft of motor 24, and a driven pulley 73 secured to the shaft 68. Shaft 68 has an axially extending bore 74 formed therein having one end communicating with a fitting 75, adapted to be connected to a vacuum source, the opposite end of the bore communicating with a centrally disposed chamber 76 formed in the manifold disc. A plurality of radially extending passages 77 are also formed in manifold disc 67, each passage having one end communicating with chamber 76 and the opposite end communicating with a pipe 78. One end of each pipe is threaded into the outer peripheral wall of the manifold and the opposite end is connected to the tubular conduit 61. Each radial passage 77 has an axial or transverse passage 79 extending therethrough which contains a spring-biased spool valve 80. Another transverse passage 81 is formed in the manifold disc which has one end communicating with the portion of radial passage 77 adjacent the end of the pipe 78 and the opposite end communicating with a radial passage 82 which has one end communicating with transverse passage 79 and the opposite end closed by a condensate drain plug 83.
Each of the spool valves 80 is biased to the right, as shown in FIG. 7, against a ring member 84 secured to the face of the manifold disc, and having a plurality of circumferentially spaced apertures 85 therein. Each of the apertures 85 is aligned with a respective spool valve 80 for establishing communication between the valve and an air pressure nozzle 86. As will be seen in FIG. 2, the nozzle 86 is carried by an arcuate arm 87 which is secured to the support 69 by bolts 88 extending through slots 89 formed in the end portions of the arm whereby the nozzle is adjustably mounted on the support 69 to thereby maintain the nozzle 86 in alignment with the apertures 85. As will be seen in FIG. 7, one end of the nozzle 86 is connected to air pressure conduit 90 and the opposite end of the nozzle is provided with an antifriction material 91 against which the ring member 84 slides during rotation of the manifold disc 67.
From the above description, it will be readily apparent that chamber 57 of each can holder will be placed under vacuum when its respective spool valve 80 is biased to the right, to open position as shown in FIG. 7, the vacuum being drawn through conduit 61, pipe 78, valve 80, passage 77, and bore 74. The chamber 57 is placed under pressure when the manifold disc 67 has been rotated to position the spool valve 80 adjacent the air pressure nozzle 86; whereupon the air pressure forces the spool valve 80 to the left, or closed position, as shown in FIG. 8, to cut off the vacuum to pipe 78. While the valve is maintained in this position, pressurized air flows through aperture 85, passage 81 and pipe 78 to the chamber 57 through conduit 61.
The operation of the transfer assembly of the present invention will be best understood by referring to FIG. 7 wherein it will be seen that when the mandrel carrier 11 moves past the air pressure nozzle 65, each decorated can 4 is sequentially blown from the mandrel 10 toward one of the suction cups 48 carried by a can holder 28. The bottom of the can is held against the suction cup through vacuum which communicates with the cup through bores 49 and 50 in the piston 46, clearance 59, chamber 57, conduit 61, pipe 78, open spool valve 80, passage 77, chamber 76 in the disc manifold and bore 74 in rotary shaft 68. With each can thus held on a respective holder, the endless chain conveyor 26 moves the can carrying holders 28 around to the oven drying conveyor 2. During the travel of the chain conveyor, the cam plates 30 and 31 cause the can holders to slide laterally on the pins 27 to facilitate the removal of the decorated can from the mandrel 10 and the depositing of the can on the pin 66 of the oven drying conveyor 2.
The chain conveyor 26 and manifold disc 67 are simultaneously rotated so that when each can carrying holder 28 is positioned adjacent a pin 66 on the oven drying conveyor 2, the spool valve 80 will be aligned with the air pressure nozzle 86, whereby the spool valve is moved to cut off the vacuum to the holder, thereby allowing pressurized air to flow to the can holder 28 to force the piston 46 outwardly therefrom whereby the decorated can is pushed onto the pin 66 of the oven drying conveyor. When the manifold disc 67 moves past the nozzle 86, the spool valve 80 will be spring biased to open position to thereby establish communication between the vacuum source and the can holder 28 which is carried by the endless chain conveyor 26 back to the mandrel carrier 11 to receive another decorated can therefrom; whereupon the cycle is repeated.
Since the transfer assembly of the present invention is adapted to be used with a continuous container printing machine, it will be understood by those skilled in the art that the can holder conveyor and associated manifold disc are continuously rotated and their structural relationship between the mandrel carrier and oven drying conveyor is such that when a decorated can is being transferred from a mandrel to a can holder, another can is being simultaneously transferred from a holder to the oven drying conveyor.