Container seaming assembly

Abstract

Described is a seaming machine for use with a container ( 22 ) and an end closure ( 28 ). The machine includes a seaming head ( 62 ) with multiple shaft assemblies ( 100 ) and a lifter table ( 60 ) located below the seaming head ( 62 ) and including multiple container stations. During use, the lifter table ( 60 ) and seaming head ( 62 ) rotate in unison about the centerline of a spindle ( 64 ). A single shaft assembly ( 100 ) is provided at each station to perform a two-step seaming operation on its corresponding container ( 22 ). In one embodiment, a seaming cam ( 66 ) is located above the seaming head ( 62 ) for moving first and second cam followers ( 116 ), ( 118 ) in the shaft assembly ( 100 ). In another embodiment, the cam followers ( 116 ) and ( 118 ) have a master/slave relationship dependent on which step of the seaming operation is being conducted. In another embodiment, a single piece plate ( 122 ) is used in a cover feed assembly ( 120 ) and provides end closures ( 28 ) to a make-up point ( 30 ).

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:  
     
         1 . A seaming machine for forming an air tight joint between a container and an end closure, the machine comprising: 
 (a) a seaming head rotatably connected to a central spindle, the head including multiple shaft assemblies; and    (b) a lifter table located below the seaming head and including multiple stations, each station capable of receiving a container;    (c) wherein during use, the lifter table and seaming head rotate in unison about the centerline of the spindle, thereby moving a stream of containers through the seaming machine; and    (d) wherein a single shaft assembly is provided at each station to perform a two-step seaming operation on a single corresponding container.    
     
     
         2 . The machine according to  claim 1 , wherein the multiple shaft assemblies are located radially outward of their respective station, relative to the axis of rotation of the lifter table and seaming head.  
     
     
         3 . The machine according to  claim 2 , wherein the lifter table includes a lifter at each station and the seaming head includes a chuck at each station; and wherein during use, each container and end closure are held at a station between a lifter and a chuck.  
     
     
         4 . The machine according to  claim 1 , further comprising a cover feed assembly for providing end closures, the cover feed assembly including a unitary plate having a lower surface, a shallow channel in the lower surface for holding end closures, and inwardly-extending flanges bounding the side walls of the channel.  
     
     
         5 . The seaming machine according to  claim 1 , wherein the shaft assembly includes first and second rollers; the first roller for performing a first seaming step resulting in partial closure of the joint and the second roller for performing a second seaming step resulting in final forming of the joint.  
     
     
         6 . The machine according to  claim 5 , further comprising a seaming cam, the seaming head and lifter table rotating relative to the seaming cam during use; wherein the shaft assembly includes a first and second cam follower arranged to follow the contour of the seaming cam as the lifter table and seaming head rotate about the centerline of the spindle; the motion of the first and second cam followers providing rotary input to accomplish the two-step seaming operation of the first and second rollers.  
     
     
         7 . The machine according to  claim 6 , wherein the first cam follower acts as a master cam follower that positions the first roller to accomplish the first seaming step, the second cam follower being a slave to the first cam follower during the first seaming step; and wherein the second cam follower acts as a master cam follower that positions the second roller accomplish the second seaming step, the first cam follower being a slave to the second cam follower during the second seaming step.  
     
     
         8 . The machine according to  claim 7 , wherein the shaft assembly includes an upright shaft having upper and lower ends and a block having opposite ends and a middle region; the first and second rollers being rotatably connected to the ends of the block about upright axes; the middle region of the block being connected to the lower end of the upright shaft; wherein during use, the block and shaft pivot jointly in a manner corresponding to the pivotal motion of the first and second cam followers in response to the contours of the seaming cam.  
     
     
         9 . The machine according to  claim 8 , wherein the first and second rollers are adjustably connected to the block.  
     
     
         10 . The machine according to  claim 8 , wherein the distance between the rollers and the centerline of the shaft is adjustable.  
     
     
         11 . The machine according to  claim 8 , wherein the block includes an eccentric seam setting device.  
     
     
         12 . The machine according to  claim 8 , wherein the block includes a height adjustment device.  
     
     
         13 . The machine according to  claim 1 , further comprising a seaming cam, the seaming head and lifter table rotating relative to the seaming cam during use; wherein the shaft assembly includes a first and second cam follower arranged to follow the contour of the seaming cam as the lifter table and seaming head rotate about the centerline of the spindle; wherein, during the first seaming step, the first cam follower acts as a master cam follower to position the shaft assembly to accomplish the first seaming step, the second cam follower being a slave that provides a complimentary motion to that of the first cam follower; and, during the second seaming step, the second cam follower acts as a master cam follower to position the shaft assembly to accomplish the second seaming step, the first cam follower being a slave that provides a complimentary motion to that of the second cam follower.  
     
     
         14 . The machine according to  claim 13 , wherein the shaft assembly includes first and second rollers; the first roller for performing a first seaming step resulting in partial closure of the joint and the second roller for performing a second seaming step resulting in final forming of the joint.  
     
     
         15 . The machine according to  claim 14 , wherein the multiple shaft assemblies are located radially outward of their respective station, relative to the axis of rotation of the lifter table and seaming head.  
     
     
         16 . The machine according to  claim 14 , wherein the lifter table includes a lifter at each station and the seaming head includes a chuck at each station; during use, each container and end closure being held at a station between a lifter and a chuck; the corresponding shaft assemblies being located radially outward of their respective station, relative to the central axis.  
     
     
         17 . The machine according to  claim 14 , wherein the shaft assembly further includes an upright shaft having upper and lower ends and a block having opposite ends and a middle region; the first and second rollers being rotatably connected to the ends of the block about upright axes; the middle region of the block being connected to the lower end of the upright shaft; wherein during use, the block and shaft pivot jointly in a manner corresponding to the pivotal motion of the first and second cam followers in response to the contours of the seaming cam.  
     
     
         18 . The machine according to  claim 13 , further comprising a cover feed assembly for providing end closures to a seaming machine, the cover feed assembly including a unitary plate having a lower surface, a shallow channel in the lower surface for holding end closures, and inwardly-extending flanges bounding the side walls of the channel.  
     
     
         19 . In a process for affixing an end closure to a container opening, the container being located at a processing station in a container closing machine; the process including a seaming operation to form an air tight joint between the end closure and the container; an improvement comprising: 
 using a shaft assembly adjacent to each processing station to perform a seaming operation on a single container during use; wherein the shaft assembly includes first and second rollers; the first roller for performing a first seaming step resulting in partial closure of the joint and the second roller for performing a second seaming step resulting in final forming of the same joint.    
     
     
         20 . The improvement according to  claim 19 , wherein the shaft assembly further includes an upright shaft having upper and lower ends, a block having opposite ends and a middle region, and a cam assembly; the first and second rollers being rotatably connected to the opposite ends of the block about upright axes; the middle region of the block being connected to the lower end of the upright shaft; the cam assembly causing pivoting of the block relative to the centerline of the shaft; and 
 wherein, during use, the cam assembly positions the block to enable the first roller to conduct the first seaming step and, once completed, pivots the block to enable the second roller to conduct the second seaming step.    
     
     
         21 . The improvement according to  claim 20 , wherein the seaming operation includes using a seaming cam and wherein each shaft assembly includes first and second cam followers located at the upper end of the shaft and in contact with the seaming cam, the cam followers adapted to transmit pivotal motion to the block to position the first and second rollers during use.  
     
     
         22 . The improvement according to  claim 21 , wherein during the first seaming step the first cam is a master cam and the second cam is a slave cam, and during the second seaming step the roles are reversed.  
     
     
         23 . The improvement according to  claim 19 , further comprising a cover feed assembly for providing end closures to a seaming machine, the cover feed assembly including a unitary plate having a lower surface, a shallow channel in the lower surface for holding end closures, and inwardly-extending flanges bounding the side walls of the channel.  
     
     
         24 . A cover feed assembly for providing end closures to a seaming machine, the cover feed assembly comprising a unitary plate having a lower surface, a shallow channel in the lower surface for holding end closures, and inwardly-extending flanges bounding the side walls of the channel.  
     
     
         25 . The cover feed assembly according to  claim 24 , wherein the channel is formed in the unitary plate by being machined out of a solid material.  
     
     
         26 . The cover feed assembly according to  claim 24 , wherein the channel is formed in the unitary plate by being molded into the plate during formation.  
     
     
         27 . The cover feed assembly according to  claim 24 , further comprising a cover feed turret located below the unitary plate and adapted to rotate relative to the unitary plate about an upright axis, the turret including a peripheral edge and a number of push pins spaced along the periphery at predetermined locations; wherein during use, the pins move end closures from one location to another within the channel.