Patent GB-878450-A (GB)
Title: Automatic sewing machine
Inventor: HAYES FRANK ANDERSON
IPC: D05B73/12
Filed: 1959-11-19
Abstract: 878,450. Sewing-machines. SINGER MANUFACTURING CO. Nov. 19, 1959, No. 39309/59 Class 112 Feed by clamps Apparatus for automatically sewing a seam of desired configuration comprises a sewing machine 7 and a traverse mechanism for carrying work relatively to the stitching point characterized by a trolley 66 mounted for universal movement in a plane parallel to the bed plate of the sewing machine, means for clamping a workpiece on to a work supporting plate 68 (see Fig. 4) carried by the trolley, a stationary pattern 129 engaged by a wheel 128 journalled in the trolley, spring means 172, 181 (see Fig. 3) biasing the trolley to hold the wheel into engagement with the pattern and means for rotating the wheel to move the trolley in a path defined by the pattern means. The apparatus described is used for automatically sewing two seams on a cuff (Figs. 14 and 15, not shown). The cuff is laid on the plate 68 and positioned with respect to the edge guides 217, 218, the latter guide being spring biased and moved into its correct position by engagement with the plate. The work supporting plate 68 is hollow and is provided with apertures 69 at the edges of its upper surface. A flap 70 is laid over the work and at the commencement of a stitching cycle the interior of the plate 68 is connected to air suction means to hold the work in place. The trolley 66 is slidable along rods 56, 57 attached to a slide element 59, the latter being slidable on fixed rods 50, 51 which are normal to the rods 56, 57. The latter rods may be levelled by eccentric bushes 63, (see Fig. 4). Each end of the rod 56 extends beyond the respective rod 50, 51 and carries a pinion 64 which meshes with a rack 65. The driving wheel 128 journalled within the trolley 66 is rotatable by a telescopic, extensible shaft-drive from the sewing machine motor through a variable speed control unit 90, solenoid operated reversible gear 99 and a belt 108. When a 'left start' button is pressed the wheel 128 rotates and the trolley and the work moves along a path corresponding to that of the pattern, and the sewing machine stitches a corresponding seam in the work. When three sides of the pattern have been traversed limit switches stop the feeding movement and the sewing machine, raise a presser foot, and release the suction. The work is removed from the plate 68, turned inside out and replaced, using the edge guides 221 and 217. As the second seam to be stitched lies within the first and starts at a different point on the work, at the stopping of the machine a right trolley shift mechanism solenoid operates a slide bar 190 to move the trolley. Another solenoid moves the portions 135, 136 of the three part pattern 129 to collapse it and allow the edge 132 of a smaller pattern disposed beneath the pattern 128 (Fig. 4) to be engageable by the wheel 129. A further solenoid operates the gear 99 to reverse the direction of the drive to the wheel 128. Actuation of a 'right start' switch starts the sewing machine, lowers the presser foot, withdraws the right trolley shift mechanism, and the wheel 128 rotates in the opposite direction to move the trolley back, along the edge of the smaller pattern to complete the stitching of the work. Limit switches operate at the end of the movement with similar effects to those described for the first seam, a left trolley shift mechanism 185 being provided to move the trolley to the starting position of the first seam. Driving clutches and brakes. The machine is driven by a power transmitter 26 having a motor 28 on which is mounted a solenoid 29 which actuates a controlling the clutch and brake mechanisms of the transmitter. The sewing machine is fitted with a needle positioner 35 which always brings the needle to its raised position when the needle is stopped. Specification 795,637 is referred to.