Patent GB-190700280-A (GB)
Title: Improvements in Sewing Machinery.
Inventor: PALSSON CARL JOHAN
Filed: 1907-01-04
Granted: 1908-01-04
Abstract: 280. Palsson, C. J. Jan. 4. Button-hole sewing- machines; button-holes, cutting; needle - bars, vibrating laterally; stopping, automatic.- Relates to a machine in which the needlebar is vibrated laterally to produce the overedge stitch and the frame carrying all the stitching - mechanism is moved by cams to cause the needle &c. to follow the shape of the button-hole while the work is held still, and consists in arranging that the special operations can be stopped and the machine used for sewing plain seams. The frame 1 is slidingly mounted on the bed - plate, is guided at the rear by a slotted plate 3 which moves over a pin 5, and carries a slotted plate 17, Fig. 3, to which the requisite movements are given by two bell-crank cam levers 24, 27 and 11, 14. The lever 11, 14 that gives the endlong movement, and the lever 24, 27 that moves the frame from one side of the button-hole to the other, are actuated by grooves in the under and upper sides of the disk 6, respectively. They are adjustably connected to the plate 17, so as to vary the size of the buttonhole, by pins 15, 28, which are carried by blocks adjustably fixed in the slots 21, 29 in the levers. The cam-disk 6 is intermittently rotated by a silent ratchet 37, having two pins 38 which grip a rim 39 on the boss of the cam-disk when the plate 37 is forced forward by a rod 41 linked to the oscillating shaft 36. The ratchet is returned by a spring, and a spring-controlled brake-detent 44 is also applied to the rim 39 The shaft 36 is oscillated from the upper shaft 90 by a bar 93, the vertical or efficient movement of which is determined by the inclination of an arm 96, to which the bar 93 is connected by a link 95. The work-clamp does not move ; it comprises a baseplate 46 and a spring-pressed upper member 53 which may be raised by a cam and lever 59. A cutter bar 61 is pivoted to a shaft 62, which is carried by swinging links 63 pivoted also to the shaft 64, and is operated by a band-lever 66. The bar 61 is in two parts, and the union sleeve 52 permits the lengthening of the bar. A cam-plate 67 co - operates with a movable collar 68 to determine the length of the cutting stroke. The needle-bar frame is oscillated about its pivot by a cam-lever 109 in opposition to a spring 108. A screw 114 determines the travel of the lever 109. The machine is stopped by a belt-lever 70, which is pivoted at 71 and held in position against the efforts of a spring by the engagement of a notch in the rod 74 with a detent. At the close of the stitching operation, a lever 80, actuated by a projection 84 on the cam-disk 6, releases the rod 74 and the machine is stopped. When a buttonhole is to be sewn over twice, the stopping of the machine is avoided by pressing the handle of the part 72 of the belt - lever. To prepare the machine for sewing plain seams, the arm 96 is moved into the vertical or inoperative position, the screw 114 is adjusted to stop the lateral vibration of the needle, the work-clamp is removed, and an ordinary feed-dog (not shown) is brought into action.