Patent GB-1027823-A (GB)
Title: Sham cuff button-holing attachment for sewing machines
Inventor: BOOTH CHARLES WHITNEY
IPC: D05B35/12
Filed: 1963-12-06
Abstract: 1,027,823. Sewing machines. PRICES TAILORS Ltd. Feb. 19, 1965 [Dec. 6, 1963], No. 48212/63. Heading D1G. A buttonhole sewing machine having a needle 26, and a work-feeding clamp 17 carried by a bracket 18 lifted at the end of a sewing operation by a bar 19 and actuated longitudinally by a feed bar 23, is provided with attachment means adapting the machine for automatically sewing a series of shown buttonholes on the cuff of the sleeve of a jacket or the like. A sleeve clamp comprises a pair of U-shaped members 10A, 10B hinged together at 11 and carried by bosses 20 slidable on a lateral bar 21 rigid with a block 22 pivoted on the bar 23. The sleeve clamp is provided with work-positioning stops 13, 14 and is swingable about the feed bar 23 for sewing oppositely-handed sleeves S and SX, the sleeve clamp being held in one or the other angular positions by the engagement of a spring-biased plunger 24, carried by block 22, with one of two cam prefaces 25A, 25B rigid with feed bar 23. The upper clamp part 10A is provided with two marks 15A, 15B respectively alignable with a mark 16 on clamp 17 for positioning the sleeve clamp in the correct starting position. Blocks 27, rigid with the bosses 20, are formed with laterally-inclined grooves 28 equal in number to the maximum number of buttonholes required and spaced from one another by the distance required between adjacent buttonholes, the grooves in the respective blocks 27 being oppositely inclined. A set of grooves is traversed in succession by a vertically-reciprocable pawl 29 which is pivoted to an actuating slide 31 and is spring-biased against an abutment face 33, Fig. 2 not shown, whereby downward movement of pawl 29 shifts the sleeve clamp one step laterally, while return movement of pawl 29 imparts no movement to the sleeve clamp, each groove 28 being relieved as at 28, Fig. 2, to allow the pawl to be withdrawn. A bar 40, rigid with the blocks 27, slidably carries at each end a microswitch 41 adjustable laterally by means of a knob 42, the spindle of which is engagable in numbered notches in a plate 43 fixed to block 27, for selecting the required number of buttonholes. A bar 44, fixed to bracket 18, has its ends adapted to actuate one or the other of the switches 41, when bracket 18 rises, according to the angular setting of the sleeve clamp. As shown, the sleeve clamp is swung to the left for sewing a sleeve 5, the left hand block 27 being positioned beneath its associated pawl 29, and the right hand switch 41 being positioned above the right hand end of bar 44. The machine is then started for sewing the first buttonhole, on the completion of which clamp 17 rises and the right hand switch 41 is actuated, whereby the slides 31 move downwards and upwards, and the left hand pawl 29 thereby shifts the sleeve clamp one step laterally. At the end of the upward stroke of slide 31, a finger 31A rigid therewith actuates a microswitch 45 for re-starting the sewing machine. The machine thereby continues to sew buttonholes in sequence until the actuating member of switch 41, in accordance with the lateral adjustment of the latter, is shifted out of the path of movement of bar 44. To prevent incorrect actuation, a ball contact 47, rigid with boss 20, engages in succession a series of depressions 48, formed in bar 20 and spaced in accordance with the buttonhole spacing, to complete the starting circuit.