Packaging

Abstract

A method and apparatus for applying a tie around the gathered open end or neck of a bag to close the bag. A feed device ( 6 ) feeds a length of tie material ( 1 ) to a former ( 3 ) where the tie material is formed into a tie loop ( 2 ) around the gathered open or neck of a bag inserted in the former ( 3 ). After forming the tie loop ( 2 ), a leading, free end of the tie material 1 is held in a gripper device ( 14 ) and the feed device ( 6 ) for the tie material ( 1 ) reversed to pull the tie material and close the tie loop ( 2 ) around the gathered open end or neck of the bag. A cutter device cuts the tie material ( 1 ) after the tying operation to allow the bag to be removed from the former ( 3 ) with the tie secured thereto. A guard ring ( 16 ) prevents tightening of the tie loop and requires the operator to use both hands to initiate removal of the guard ring so that the tie loop ( 2 ) cannot be tightened with a part of the operators hand or fingers in the former ( 3 ). In one embodiment, the gathered open end or neck of the bag is inserted into the former ( 3 ) with a vacuum device.

1 . Apparatus for applying a tie to a bag to close the bag, the apparatus comprising a former configured to receive a length of tie material and form the tie material into a tie loop, and means for tightening the tie loop around a gathered open end or neck of a bag received within the tie loop to form and secure a tie closing the bag. 
   
   
       2 . Apparatus according to  claim 1  wherein, the former comprises an annular ring member with an internal surface defining an opening in which the gathered end or neck of a bag can be inserted, and the internal surface has a groove configured to form the tie material into the tie loop. 
   
   
       3 . Apparatus according to  claim 2  wherein, the groove extends circumferentially around the internal surface for substantially two complete turns that cross-over at a plurality of circumferentially spaced apart locations whereby, when the tie loop is tightened, the tie material forms a knot where the turns cross-over. 
   
   
       4 . (canceled) 
   
   
       5 . (canceled) 
   
   
       6 . Apparatus according to  claim 2  wherein, one end of the groove is arranged to receive a leading end of the tie material from a feed device and the other end of the groove is arranged to deliver the leading end to a gripper device, the feed device and gripper device being configured such that the tie loop contracts and forms the tie around the gathered open end or neck of the bag when the tightening means is actuated. 
   
   
       7 . (canceled) 
   
   
       8 . Apparatus according to  claim 6  wherein, the feed device is reversible to tighten the tie loop to form the tie when the leading end of the tie material is held by the gripper device. 
   
   
       9 . Apparatus according to  claim 8  wherein, the feed device includes a guide pulley and a drive belt arranged to grip the tie material between the guide pulley and drive belt, and rotation of the guide pulley in one direction feeds tie material to the former and rotation of the guide pulley in the opposite direction tightens the tie loop. 
   
   
       10 . (canceled) 
   
   
       11 . (canceled) 
   
   
       12 . Apparatus according to  claim 6  wherein, the feed device is arranged to receive tie material from a continuous length of tie material stored on a reel or drum and feed the tie material to the former, and a cutting device is provided to cut the tie material between the feed device and the former. 
   
   
       13 . Apparatus according to  claim 2  wherein, the former is provided with a guard ring received in the opening in a first position in which the guard ring covers the groove preventing the tie loop being tightened, and the guard ring is movable to a second position clear of the groove allowing tightening of the tie loop. 
   
   
       14 . (canceled) 
   
   
       15 . Apparatus according to  claim 13  wherein, the guard ring confines a leading end of the tie material to follow the groove as it is fed through the former. 
   
   
       16 . Apparatus according to  claim 1  wherein, means is provided for actuating the tying operation that is responsive to two operations within a pre-determined time that requires the operator to use both hands, one for each operation. 
   
   
       17 . (canceled) 
   
   
       18 . (canceled) 
   
   
       19 . Apparatus according to  claim 1  wherein, a vacuum insertion device is provided that draws the gathered open end or neck of a bag into the former, and wherein the vacuum device incorporates a guard ring to prevent the tie loop being tightened until the bag is located in the correct position and the guard ring is withdrawn. 
   
   
       20 . (canceled) 
   
   
       21 . (canceled) 
   
   
       22 . A method of closing a bag with a tie comprising the steps of providing a tie material, forming the tie material into a tie loop in which the tie material crosses over at a plurality of circumferentially spaced positions, and tightening the tie loop to form and secure a tie around the gathered open end or neck of a bag received in the tie loop to close the bag. 
   
   
       23 . A method according to  claim 22  wherein, the tie loop comprises substantially two complete turns that cross-over to form a double knot to secure the tie when the tie loop is tightened. 
   
   
       24 . A method according to  claim 22  wherein, the tie is formed by feeding a leading end of the tie material through a former to form the tie loop and gripping the leading end of the tie material while applying a force to the tie material to tighten the tie loop. 
   
   
       25 . A method according to  claim 24  including the step of cutting the tie material after the tie is formed, removing the bag from the former with the tie loop secured thereto, and feeding the leading end of the tie material through the former to form a new tie loop for the next bag. 
   
   
       26 . (canceled) 
   
   
       27 . (canceled) 
   
   
       28 . (canceled) 
   
   
       29 . A method according to  claim 22  wherein, the tie is made of plastics material coated with a plastics material that softens or melts during the tying operation and sets to prevent the knot being undone. 
   
   
       30 . A method according to  claim 29  wherein, the tie comprises a length of plastics material of substantially uniform circular cross-section. 
   
   
       31 . (canceled) 
   
   
       32 . (canceled) 
   
   
       33 . (canceled) 
   
   
       34 . A method according to  claim 22  wherein the tie is made of metal wire or plastic coated metal wire. 
   
   
       35 . A method according to  claim 22  including the step of providing a guard for preventing tightening of the tie material until the guard has been removed. 
   
   
       36 . A method according to  claim 35  wherein the step of removing the guard requires two operations by the operator—one for each hand—within a pre-determined period of time. 
   
   
       37 . (canceled) 
   
   
       38 . (canceled) 
   
   
       39 . (canceled) 
   
   
       40 . (canceled)