GB692078A - Work-jogging attachments for sewing machines - Google Patents

Abstract

692,078. Sewing-machines. FAIRWEATHER, W. C. (Singer Manufacturing Co.). Sept. 14, 1951, No. 21619/51. Class 112. Buttonhole-sewing attachments. -A workjogging attachment comprises a frame 20, for attachment to the presser-bar, with its longitudinal centre-line x intersecting the path of the needle 14, a presser-foot shank 27 carrying a work-engaging foot 25, and mechanism for imparting movements transverse to the line x to a point on the shank 27 ; the shank is connected to the frame at a second point, for controlling the amplitude of movement of the foot 25, provided by a block 54 which is adjustably clamped to the frame 20 at any point along a line parallel to the line x including a point laterally opposite to the needle and which is slidably engaged by guide surfaces 50 formed on the presser-foot shank substantially parallel to the line x. In the form shown the mechanism comprises the usual needle-bar-actuated cam-wheel 33, oscillating lever 35 pivoted to the frame at 34, pinion 39 carried by the lever, and pattern rack 41 carried by the presser-foot shank 27, the rack being interchangeable with others of different form; the block 54 is adjustable along a slot 53 formed in the frame 20, and the guide surfaces 50 are formed by the sides of a slot formed in a lateral extension 48 of the shank 27. As the left-hand end of the shank 27 is oscillated laterally the shank also has a slight reciprocation on the block 54, the resulting motion of the foot 25 being an oscillation about a point on the line x opposite the block 54. When the block is opposite the needle the axis of oscillation of the foot coincides with the needle, so that a straight seam is sewn; lateral recesses 58 in the slot 53 permit the block 54 to be adjusted laterally so that the foot is carried sideways to enable a straight seam offset from the line x on either side of it to be made, for example in the production of bound buttonholes, the recesses 58 being arranged on an arc centred on the point of engagement between the pinion 39 and rack 41, so that the movement of the part of the work beneath the needle is absolutely perpendicular to the line x.