Patent GB-191505213-A (GB)
Title: Improvements in or relating to Buttonhole Sewing Machines.
Inventor: MELLERISH-JACKSON WILLIAM JOHN
IPC: D05B3/08
Filed: 1915-04-06
Abstract: 5213. Jackson, W. J. Mellersh-, [Reece Buttonhole Machine Co.]. April 6. Button - hole sewing - machines. - In a machine having rotary stitch-forming devices and a workclamp to which both lateral and longitudinal movements are imparted, the work-clamp is selfcontained and readily detachable from the machine. The upper members 32 of the clamp are mounted loosely upon their axle 33 and are opened and closed by lever-arms secured upon the axle. The axle is turned by means of an arm on a second shaft 40 which may be operated either by a handlever 44 or automatically from the feed - cam through a hook member 47. When the clamp is closed it is locked by a latch which is released at the completion of a button-holing movement by engagement with a fixed cam on an arm 53. The clamp is divided longitudinally and the parts which are pivotally mounted on the clamp-plate are separated after the clamp is closed by a cam-lever which contacts with a fixed cam as the clamp is moved from cutting position to stitching position. The clamp is slidingly mounted in a plate to which lateral vibrations are imparted and is moved longitudinally upon the plate by a latch connexion with a cam-actuated plate. The latch-connexion is disengaged by hand in order to remove the clamp from the machine. The movement of the clamp from cutting position to stitching position and back again is effected by the feed-cam when this is being driven rapidly through skew gearing 117, Fig. 3, and a clutch 126 on an auxiliary shaft. The depression of the starting lever releases a bar 110 which presses upon a plate 28 and causes it to close the clutch 126. When the clamp reaches stitching position, the plate 28 is moved by the feed-cam and disengages the clutch 126. During stitching, the feed cam is rotated slowly by ratchet gearing. At the close of the stitching, the feedcam causes the closing of the clutch 126 and at the completion of the rearward movement the cimplate 63 carrying the work-clamp contacts with a lever 113 and, by means of a wedge 112, opens the clutch 126. The anvil 87, Fig. 11, is pivoted at 88 and normally rests in an inoperative position. It is turned into its operative position as the workclamp is closed, by means of a lever 97. Loop - stitching.-The curved under needle 123, Fig. 11, is carried by a shaft 142 having an arm coupled by a link to a vertically - reciprocating actuator plate 149 mounted in the rotary frame. The looper 145 is pivotally mounted on a leverplate 158 actuated by means of a cam-slot 160 and a bowl on the actuator plate. The looper is given a small needle-avoiding lateral oscillation upon the lever-plate. Stopping-gear.-Tbe starting lever comprises the upright pivoted trigger post 102, Fig. 1, and the finger-plate 100 which can be turned upon the post. The plate carries a pin 105 and, when the plate is in its operative position, the pin 105 enters a hole in the machine frame when the starting lever is depressed. When the finger-plate is swung away from its operative position the pin 105 prevents the depression of the starting-lever. The machine is stopped in a predetermined position by the pivoted device 230, Fig. 8. Normally, it is held to the right of the position shown, but in stopping the machine, it is released and is spring-pressed towards the left. At first an arm 287 which bears against a drum on the shaft restrains the device, but at the right moment the arm 287 passes into a gap in the drum and a lug 234 engages with a stop, which may be resilient, on the shaft. This movement of the device is used to actuate the belt shipper gear and the upward movement of the lug 234 is transmitted by the stock 235 to a brake lever 254.