Patent GB-1088276-A (GB)
Title: Wrapping machine
IPC: B65B9/02
Filed: 1964-10-08
Abstract: 1,088,276. Wrapping-machines. KEYES FIBRE CO. Oct. 8, 1964 [Aug. 3, 1964], No. 41043/64. Heading B8C. A wrapping machine conveys articles towards two transversely positioned sheets of wrapping material which have adjacent ends joined and are fed at a rate co-ordinated with the speed of the articles so that the sheets are engaged by an article and form two layers, one on each opposite side of the article, and the layers are joined together to form an open ended tube about the article. A moulded tray 14 from a dispersing unit (16) is deposited on a conveyer (12), manually filled with fruit, at stations (18) and passed on to a belt conveyer 42 where it operates a trip 144 to raise a trigger 168 and stop bar 166 on a second belt conveyer 44 and engages wrapping material derived from two rolls 336, 420 which are driven intermittently by power rollers 334, 350, 408, 410, the individual webs 366, 436 from each reel being heat sealed together at the ends in a position transverse to the path of the conveyer 42 by seal bars 200, 202 described below. Movement of the tray against the web causes the raising and lowering of two movable arms 438, 392 respectively which in turn actuate limit switches (240, 248) to cause the rollers 334, 350, 408, 410 to feed wrapping material from the rolls 336, 420 which is taken up by the tray as it is moved on to the second belt conveyer 44. When the tray engages the trigger 168 and its associated stop bar 166 which operate a switch 176 the conveyers 42, 44 are stopped while the continuing feed of the wrapping material permits the arms 438, 392 to return to their original positions and by actuating the switches (240, 248) eventually stop further feeding. Additionally the switch 176 operates fluid motors 210, 230 to raise and lower the heat sealing bars 200, 202 which actuate a switch (242) to limit the movement of the sealing bars and also control the time during which they remain in contact to effect a transverse seal in and severance of the two layers of wrapping material behind the tray and so form an open ended tube around the tray. During the return of the seal bars operation of the switch (242) restarts the belt conveyers 42, 44 so that the partially wrapped tray is fed on to a third belt conveyer 46 where it operates another trip 144 to stop the third belt conveyer 46 and actuate two pairs of sealing bars 248, 246 which in their movement actuate limit switches (288) to limit their movement and operate time switches to control the period during which the bars in each pair remain in contact to form seals along the ends of the tube of wrapping material and sever the excess which is removed by a suction device (324). The return of the heat bars 246, 248 activates the switch (288) to restart movement of the belt conveyer 46 which carries the wrapped tray beyond the wrapping machine to another conveyer (20) for passage through a heating chamber (22) to heat shrink the wrapping material. The machine can be adjusted so that the web from the roller 336 is passed over a printing roller 382. Provision is made for adjustment of the position of the heat sealing bars and feed of the wrapping material to accommodate different size trays. Static eliminators 430, (346) are provided for the rolls 420, 336.