Sealing film indenting device and cup sealer incorporating such an indenting device

Abstract

A sealing film indenting device includes an indentation cutter pad, a movable rod movable relative to the indentation cutter pad along a moving axis, an indentation cutter mounted to the movable rod, and a drive unit. The drive unit is coupled to the movable rod for driving the movable rod to move along the moving axis between a standby position where a film lidding receiving space defined between the indentation cutter and the indentation cutter pad for receiving a film lidding to be indented, and an indentation cutting position where the indentation cutter moved toward the indentation cutter pad across the film lidding to cut indentations on the film lidding.

What is claimed is: 
     
         1 . A sealing film indenting device adapted to indent a film lidding, comprising:
 an indentation cutter pad;   a movable rod movable relative to said indentation cutter pad along a moving axis, and including first and second end portions that are opposite to each other along the moving axis and that are respectively proximate to and distal from said indentation cutter pad;   a roller mounted to said second end portion of said movable rod and rotatable about a rotation axis that is perpendicular to said moving axis;   an indentation cutter mounted to said first end portion of said movable rod, and having an indenting edge that faces said indentation cutter pad; and   a drive unit including
 a push-pull solenoid that is disposed on one side of said roller along a drive axis that is perpendicular to said moving axis and said rotation axis, and that includes a solenoid body and a solenoid actuated plunger extending from said solenoid body and driven movably by said solenoid body along said driving axis, and 
 a guide block disposed on said drive axis, coupled co-movably to a distal end of said solenoid actuated plunger, and having an inclined cam surface that is in slidable contact with a circumferential surface of said roller such that the movement of said solenoid actuated plunger along the drive axis drives said movable rod to move along the moving axis between a standby position where said movable rod is positioned away from said indentation cutter pad, with a film lidding receiving space defined between said indentation cutter and said indentation cutter pad for receiving said film lidding to be indented, and an indentation cutting position where said movable rod is positioned close to said indentation cutter pad, with said indentation cutter moved toward said indentation cutter pad across said film lidding to cut indentations on said film lidding with said indenting edge. 
   
     
     
         2 . The sealing film indenting device as claimed in  claim 1 , wherein said indentation cutter has a body portion fixed to said first end portion of said movable rod, and a plurality of indentors projecting from said body portion, said indentors together defining said indenting edge. 
     
     
         3 . The sealing film indenting device as claimed in  claim 1 , wherein:
 said sealing film indenting device further comprises a housing assembly which includes a base wall, a cover opposite to and spaced apart from said base wall in the direction of said moving axis, and a surrounding wall connected between said base wall and said cover;   said base wall, said cover and said surrounding wall together define a housing space for accommodating said roller and said drive unit;   said base wall has a bore disposed on said moving axis, said movable rod extending from housing space out of said housing assembly via said bore; and   said indentation cutter pad includes a vertical fixing plate attached outwardly to said base wall and a horizontal plate spaced apart from said base wall in the direction of said moving axis.   
     
     
         4 . The sealing film indenting device as claimed in  claim 3 , wherein:
 said housing assembly further includes a positioning stud protruding from said base wall inwardly of said housing space in the direction of said moving axis;   said movable rod further includes a rod shaft connected between said first end portion and said second end portion, and a retaining plate positioned circumferentially around said rod shaft, said retaining plate having a positioning hole for passage of said positioning stud along the direction of said moving axis;   said sealing film indenting device further comprises a return spring sleeved on said movable rod with two ends thereof abutting against said retaining plate and said base wall, respectively; and   said return spring is compressed to bias against said retaining plate so that said retaining plate is resiliently urged in the direction opposite to said base wall when said movable rod is driven to said indentation cutting position.   
     
     
         5 . The sealing film indenting device as claimed in  claim 3 , wherein:
 said housing assembly further includes a positioning roller with two ends connected to said surrounding wall; and   said positioning roller is axially disposed along the direction of said rotation axis, is in contact between said guide block of said drive unit and said cover, and is rotatable with the movement of said guide block as driven by said solenoid actuated plunger along the direction of said drive axis.   
     
     
         6 . The sealing film indenting device as claimed in  claim 3 , wherein:
 said indentation cutter pad further includes an anvil, said anvil having a groove that is open to said indentation cutter and surrounded by a cutting edge;   said indentation cutter is inserted into said groove when said movable rod is driven to said indentation cutting position to cut indentations on said film lidding with said indenting edge along said cutting edge; and   said film lidding receiving space is defined between said anvil and said indentation cutter when said movable rod is at said standby position.   
     
     
         7 . A cup sealer adapted for heat sealing a film lidding supplied along a conveying path by a loaded sealing film roll on an open end of a cup, comprising:
 a conveying device including a feeding reel for advancing said sealing film roll loaded thereon, and a take-up real for recovering the remaining film waste thereon;   said sealing film indenting device as claimed in  claim 1 , said sealing film indenting device being disposed on said conveying path between said feeding reel and said take-up reel, with said film lidding passing through said film lidding receiving space of said sealing film indenting device during movement along said conveying path;   a cup support platform disposed on said conveying path between said sealing film indenting device and said take-up reel, said cup support platform being adapted for carrying said cup to position corresponding to said film lidding and holding said cup in place; and   a heated platen device disposed on said conveying path between said sealing film indenting device and said take-up reel and on top of said cup support platform, said heated platen device being adapted for forcing said film lidding into engagement with said cup to heat-seal said film lidding to said cup, with the remaining film waste moving along said conveying path to wind onto said take-up reel.