Patent GB-1048646-A (GB)
Title: Conveyor sewing machine
IPC: D05B33/02
Filed: 1963-08-08
Abstract: 1,048,646. Sewing machines. UNION SPECIAL MACHINE CO. Aug. 8, 1963 [Aug. 8,1962], No. 31280/63. Heading D1G. A sewing machine comprises a lower conveyer belt, an upper and yieldable conveyer belt, and power-driven auxiliary feed means operating on the work in advance of the presser foot for assisting the passage of work under the latter, the auxiliary feed means being free to move upwardly substantially independently of the upward movement of the presser foot. As shown, lower endless belts 30 are mounted on end rollers, one of which is driven via a variablespeed gear box, and the top runs of the belts pass over a work table 29. An upper endless belt 39 is mounted on end rollers 48 carried by a frame 49 which is connected by rods 51 to a horizontal pivoted shaft. The bottom run of belt 39 engages idler rollers 50 carried by frame 49. One end roller 49 is driven by a shaft 54 having a universally jointed connection to a variable speed gear box. The presser foot 68, co-operating with feed dogs 67, is carried by a lever 69 which is mounted for pivotal movement both vertically and horizontally and is biased downwardly by a light spring 70. A plate 69a, loosely mounted on lever 69, journals a feed wheel 36 which has two work-engaging surfaces. Feed wheel 36 is located in front of the presser foot and is connected by a flexible shaft 37 to a variable feed gear box. The arrangement is such that work 21, 22 on approaching the stitching point initially raises wheel 36 independently of the presser foot 68 to facilitate introduction of the work by wheel 36 under the lightly spring-loaded presser foot. A bar 23 positioned on table 29 in advance of the stitching point has a hollow portion which increases in depth in the direction of work feed, and through which a stream 25 of compressed air is directed on the lower workpiece 21 for straightening or uncurling the edge thereof. A tube 24, mounted on frame 49, is formed with perforations through which a stream 27 of compressed air is directed downwardly on the upper workpiece 22 for straightening or uncurling the edges thereof and thereafter holding said edge against the already straightened edge of the lower workpiece. The edges are trimmed by a stationary knife 40 positioned after wheel 36 and ahead of the needle, the trimmings being carried away by a shoot 83. A pivoted blade 65 positioned at the rear of the needle, is arranged to be oscillated, for cutting the thread chain, under the control of a photo-cell 71 which is mounted on frame 49 and acts when the trailing end of a workpiece passes thereunder. A pair of spaced photocells 42, 43, Fig. 4 (not shown), positioned at the loading point of the belts 30, are arranged to stop the driving motor when neither detects work thereunder. The completed workpieces are stacked on a pivoted arm 58, Fig. 7 (not shown), oscillated by means 62 under control of a photo cell 60 which is positioned above the discharge end of belts 30 and acts when the trailing end of a workpiece passes thereunder. In a modification feed wheel 36 is replaced by a further upper belt supported by the leading roller 48 and a roller 50 so positioned as to press said belt upon the work immediately in advance of the presser foot.