Abstract:
A product bagger and method where products are placed in inflated lead bags on a bag assembly without actuating a sensor for shutting down the bagger.

Description:
FIELD OF THE INVENTION 
   The invention relates to product baggers of the type in which an indefinite length shingled bag assembly is fed to a workstation where products are placed in lead bags, and to related methods. 
   BACKGROUND OF THE INVENTION 
   Foods products, such as meat, cheese and the like, are conventionally packaged in plastic bags using an automated bagger of the type described in U.S. Pat. No. 6,837,023. The bagger feeds empty lead bags mounted on tapes in a shingled bag assembly along a workstation surface. The lead bag in the assembly is inflated and a product is inserted into the bag. The filled bag is then stripped from the bag assembly and sealed and the tape is drawn into a tape slot extending across the workstation surface and wound onto a reel under the workstation. Winding of the tape feeds the next bag in the shingled assembly to the workstation surface, the bag is inflated by an air blast and the cycle is repeated. 
   When the lead bag is feed along the workstation surface, the leading end of the bag activates a trigger extending above workstation surface adjacent the slot. Trigger activation sends a signal to the bagger to halt feeding the bag assembly. This prevents the bagger from winding unfilled bags attached to the tape around the reel and prevents bag waste. 
   During high-speed operation of the bagger, a bagger operator will load product into a moving lead bag before the bag activates the trigger. The operator will rapidly load product into the moving lead bag as soon as the bag is inflated and then remove the loaded bag from the workstation to prepare for loading the next bag. The leading ends of the bags do not engage the trigger. 
   The operator may during high speed loading, accidentally move the product against the trigger as the product is moved into a moving lead bag. Accidental activation of the trigger deactivates the bagger and slows product packing. The operator must wait for the bagger to resume feeding the bag assembly before product packaging can resume. 
   In the case of baggers that include printers, accidental activation of the trigger will further slow operation of the bagger as the printer must reset before product packaging can resume. 
   Therefore, there is a need for an automated bagger and method that allow efficient, high-speed loading of moving bags delivered to a workstation without inadvertent deactivation of the bagger. The bagger must shut down when a lead bag is not loaded. 
   SUMMARY OF THE INVENTION 
   The invention is an automated bagger and method for improved high-speed bagging. The bagger has a sensor located in the tape slot below the workstation loading surface, out of the path of the product during loading into a bag. Loaded of products cannot stop the bagger. 
   If the bagger draws a lead bag on the bag assembly from the workstation into the tape slot, the sensor detects the leading end of the bag in the slot and stops the bagger reel from further feeding the bag assembly. The location of the sensor below the loading surface prevents accidental halt of bag feeding during high-speed operation of the bagger. 
   The invention improves bagging speed and efficiency. 
   Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawings illustrating the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side view of a bagger; 
       FIG. 2  is a view of overlapped or shingled bags in a bag assembly; and 
       FIG. 3  is a side view of  FIG. 2 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   The bagger  10  disclosed herein relates to the bagger of Glatfelter U.S. Pat. No. 6,837,023, the disclosure of which is incorporated herein by reference in its entirety 
     FIG. 1  illustrates bagger  10  having a frame  12 , a workstation  14  having a work surface  15  at the top of the frame and an optional bag printer assembly  16  mounted on one side of frame  12 . An indefinite length shingled bag assembly  18  is fed from bag assembly source or box  20  mounted on the bottom of frame  12 , through printer assembly  16  and onto workstation surface  15 . The printer assembly prints desired information, typically date and source information, on each bag in the bag assembly. 
     FIG. 2  illustrates a portion of assembly  18 . The assembly includes two spaced, parallel indefinite length adhesive elongate members or strips  22 . Generally rectangular shingled plastic bags  24  are adhered to strips  22 . The assembly  18  is fed from box  20  to station  14  downstream in the direction of arrow  26 . 
   Each bag  24  is made from thin plastic film and has opposed rectangular sides  28  (See  FIG. 1 ), an open lead end  30 , sealed trailing end  32  and sealed edges  34  extending between ends  30  and  32 . Each bag extends a distance L along assembly  18 , as measured between ends  30  and  32 .  FIG. 3  illustrates that a lead portion  36  of each bag side  28  adjacent strips  22  is adhered to the strips to hold the bags in the bag assembly. Portions  36  extend a short distance from lead bag ends  30  toward trailing bag ends  32  and are continuous along the assembly. The trailing portions  38  of the bags are shingled or overlie each other, as shown in  FIG. 3 , and are not joined to strips  22 . The trailing portions  38  may have a length along the assembly considerably greater than the length of adhered lead portions  36 . 
   As shown in  FIG. 1 , bag assembly  18  is fed from box  20  to printer assembly  16  with strips  22  on the top of the bag assembly and bag upstream trailing portions  38  hanging down from the bottom of the assembly. The bag assembly is fed around lower roller  40 , through printer assembly  16 , around upper roller  42 , around the rounded edge  44  of workstation  14  along and to surface  15  slot  46  extending through the workstation. 
   Strips  22  extend through the slot  46  and are wound on reel  48 . A drive motor (not illustrated) rotates reel  48  in the direction of arrow  50  to feed assembly  18  from box  20 , through printer assembly  16  and to station  14 . 
   Bagger  10  includes an air nozzle  52  located below surface  15 . The nozzle is connected to a source of compressed air. During operation of the bagger, the nozzle  52  continuously blows compressed air through an opening in station  14  toward the open lead end of each bag  24 . The air blast from nozzle  52  inflates the lead bag, as illustrated in  FIG. 1 , to permit an operator to insert a product to be packaged within the open bag and then remove the product and bag from strips  22 . The bag is then sealed closed. If desired, air in the bag may be removed to vacuum pack the product. 
   Micro-switch  54  is mounted on workstation  14  and is electrically connected to sensor  56  located in workstation  14  at slot  46  under work surface  15 . Sensor  56  may be an optical sensor that faces the slot and detects a bag  24  fed into the slot. As a lead portion  36  of a bag  24  passes in front of sensor  56 , the sensor detects the presence of the lead portion and sends a signal to activate switch  54  to stop rotation of reel  48  and further feeding of bag assembly  18  through bagger  10 . 
   The operation of bagger  10  will now be described. 
   An indefinite length of bag assembly  18  is folded in box  20  so that when a length of the assembly is pulled from the box toward optional printer assembly  16 , as illustrated in  FIG. 1 , adhesive strips  22  are on the upper side of the assembly, and plastic bags  24  are on the lower side of the assembly with the lead bag portions  36  adhered to strips  22  and the shingled trailing bag portions  38  extending rearwardly or upstream along the assembly  18  free from the strips. The lead portions  36  overlap each other along the length of the bag assembly, as illustrated in  FIG. 2 . 
   The lead end of the bag assembly is fed around roller  40 , and through optional bag printer assembly  16 . The lead end is then fed around roller  42 , around workstation edge  44 , along surface  15  and into slot  46 . The bags at the end of the assembly extending past printer assembly  16  are stripped away and the two adhesive strips  22  are attached to reel  48  so that rotation of the reel  48  by the drive motor in the direction of arrow  50  feeds the bag assembly  18  from box  20  past printer assembly  16  and to station  14  in the direction of arrow  26 . 
   The control circuitry for bagger  10  activates the motor to rotate reel  48  and feed bag assembly  18  downstream across surface  15 . The air blast from nozzle  52  inflates the moving lead bag as shown in  FIG. 1  so that an operator may place a product in the bag and then remove the bag and product from strips  22 . Placement of the product in the bag does not trigger sensor  56 . The bag is then sealed conventionally. High speed bagging continues with the operator placing products in moving lead bags which are fed continuously along the surface  15  without interruption. 
   In the event a product is not placed in a lead bag, the bag is fed into slot  46  and triggers sensor  56  to stop feed of the bag assembly. Upon removal of the bag the sensor is deactivated and bag feeding and loading recommence. 
   While I have illustrated and described a preferred embodiment of my invention, it is understood that this is capable of modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.