Patent GB-1449057-A (GB)
Title: Apparatus for handling flat work pieces
IPC: B65H45/04
Filed: 1973-08-09
Abstract: 1449057 Folding sheets J H WEIR S P BEHN and R M BEHN 9 Aug 1974 [9 Aug 1973 37854/73 Heading D1S A sheet handling apparatus comprises a draping conveyor 4 having a narrow upper margin over which individual folded sheets 2 can be draped in longitudinally spaced relation with at least the lower portion thereof exposed and sheet draping means for sequentially placing individual folded sheets on the upper margin of the conveyor 4 so that each folded sheet is formed with a fold at one end thereof and the portions thereof on each side of the fold hang down from the upper margin of the conveyor where these portions are exposed. As shown in Fig. 1, in units 1, 1', sheet material is unwound from rolls 3, 3', severed into sheets 2, 2' and draped, at stations 1a, 1a', onto conveyor 4, 4' which are intermittently moved to convey the sheets to sewing stations 6, 6', at which the cut edges are hemmed, and then to inlet stations 8a, 8a' of a common folding unit 8 from which the folded sheets are carried by a conveyor 10 to a packaging station (not shown). In each unit 1, 1', Fig. 2, the sheet material 2 passes from the roll 3 mounted on an undriven shaft 12 to pass between a roller 14 and an intermittently-driven endless conveyor 16 which comprises spaced narrow belts. At a cutting station 21, a circular cutting wheel 34a is carried by the lower run of an endless conveyor 32. Sheet material raising fingers 35 are arranged between the belts of the conveyor 16 in the vicinity of the wheel 34a to facilitate cutting. When the leading edge of the sheet material is detected by a photoelectric sensing means S3, the conveyor 16 is arrested and either a motor 36 or a motor 36 is is energized to drive the conveyor 32 to move the wheel 34a from left to right or right to left, respectively, of Fig. 3, to effect severing. When the wheel 34a reaches the limit of its travel it contacts a switch Sl or S2 to terminate energization of the motor 37 or 36, respectively. and re-start the conveyor 16. Pivoted arms 44 of a sheet pushing means 40 are moved outwardly by a cylinder 48 to push a portion of the sheet 2 onto the conveyor 4 which, preferably, comprises an intermittently-driven V-belt 42. Outward movement of the arms 44 causes rollers 53, on a portion 50a of a pivoted arm 50b, to be removed from contact with the conveyor 4 to permit the sheet to be draped over the conveyor 4 whilst it is stationary, links 51 connecting the arms 44 to the arm 50b. Spring means 44a on the arms 44 apply pressure to hold the sheet on the conveyor 4 as a fold 54 is formed therein, Fig. 4. When the position at which the fold 54 is located approximately mid-way along the sheet, the trailing edge of the sheet leaves a photoelectric sensing means S4 which causes the cylinder 48 to retract the arms 44 so that further downward movement of the sheet causes it to drop vertically until it leaves contact with the conveyor 16 to complete the draping operation. The rollers 53 engage the draped sheet to hold it upon the conveyor 4. When the trailing end of the sheet clears a photoelectric sensing means S5, the conveyor 16 is stopped. On completion of a hemming operation, the conveyor 4 is advanced through a fixed distance somewhat greater than than the sheet length and the conveyor 16 is started so that when the leading edge of the unsevered sheet material reaches the means S3, the cutting operation is repeated. When the sheet moves away from the station 1a upon the conveyor 4, Fig. 8, it moves along metal skirts 60 extending along the belt 42 and beneath the lower run of a belt 63 and beneath rollers 65. When the leading edge of the sheet reaches the inlet of the station 6, the conveyor 4 is arrested. The station 6 comprises sewing tables 62a, 62b, Figs. 1 and 8, having sewing units 66a, 66b thereon. Operators, stationed at the tables 62a, 62b, may first form end stitches in the trailing ends of a partially stitched sheet 2c and then, not necessarily in exact synchronism, grab one of the cut edges of the sheet 2b and initiate folding and stitching thereof. As each operator pushes the sheet 2b into the sewing unit, the leading edge thereof passes over a photoelectric sensing means S6a, or S6A to start the conveyor 16 and the conveyor 4. As the cut edges of the sheet 2b are hemmed, the sheet 2c is moved under rollers 67, Fig. 10, to the inlet 8a of the unit 8. At the inlet 8a, a photoelectric sensing means S7, Fig. 1, causes a folding blade 72, Fig. 10, to be moved by a cylinder 74 against the sheet 2d to bring it within jaws of a clamping unit 80. As the blade 72 advances, the rollers 67 are removed from contact with the sheet 2d through links 68a, 68b, 68c, 68d, the link 68a being connected to the piston rod 75 of the cylinder 74. The unit 80 comprises channel members 81, having rollers running on tracks 83 extending between the stations 8a and 8a', and three jaw assemblies 80a, 80b, 80c each comprising members 82, 82', Figs. 12 and 13, projecting from an outer sleeve 86 and members .84, 84', projecting from a rod 88 rotatable within the sleeve 86. The sleeve 86 and the rod 88 terminate in pairs of operating arms 90, 92 connected by springs 94. When the unit 80 is initially in a position adjacent one of the stations 8a or 8a', the jaw members are open so that forward movement of the respective folding blade 72 or 72' brings the sheet between the members 82, 84 or 82', 84', notches 96, 96' in the blades 72, 72' providing clearance for the jaw members. An actuator 98 or 98' carried by the blade 72 or 72' engages the arms 90, 92 to close the jaws 82, 84 or 82', 84' to grip the sheet. The presence of the unit 80 is sensed by a microswitch S8 or S8' at the station 8a or 8a' and, upon contact of a control arm 97 or 97' on the blade 72 or 72' with a microswitch S9 or S9', a conveyor 85 is attached to move the unit 80 away from the station 8a or 8a'. When a photoelectric sensing means S10 senses the presence of the unit 80, it inhibits operation of the blades 72, 72' and the members 82, 84, or 82', 84' are opened by contact of the arms 90, 92 with pins 100, 100'. When the unit 8 contacts the switch S8' or S8, an air or hydraulic cylinder 114, Fig. 10, lowers a folding blade 110 to press the sheet through a slot (115), Fig. 11 (not shown), in a folding table and between two rotating rolls (116), (118), to form a cross-fold in the sheet. Other cross-folding elements (not shown) may be located in the unit 8.