GB259855A - Needle mechanism for sewing machines - Google Patents

Abstract

259,855. Fairweather, W., (Singer Manufacturing Co.). May 10, 1926. Loop-stitching; needle-driving machanism, disconnecting. - In sewing-machines having both upper and lower thread-carrying implements and a stop motion device means is provided for dis. connecting the lower thread carrying implement from the drive so that it may be projected above the work support for threading. Means is also provided for ensuing the reconnection of the parts on starting the machine. The device is described in connection with a button-hole sew ing-machine having stitch-forming devices of the type described in Specification 15049/15 and com prising a lower curved needle 2 supported in a rotary turret 3. The needle 2 is vibrated by a link 21 connected to a head 22 mounted on a shaft 23 slidable in the turret and connected to a parallel shaft 26 by an arm 27. The shaft 26 is reciprocated by a lever 33 connected to the shaft 26 by a link 32 and actuated through a coaxial lever 34 and a link 38, and crank 39, on a shaft 40. The lever 34 is connected to the lever 33 by a spring pin 44 which may be withdrawn from its seating so as to allow the needle 2 to be projected above the work-plate when the machine is stopped. In a modification a lever 133 linked to the shaft 26 is actuated by a link 136 pivoted on a crank-pin 137 projecting from a disc 138 coaxially pivoted in the end of the shaft 40. The disc is looked to the enlarged head of the shaft by a pin 144 stressed by a spring 147 housed in a slot 148 in the disc 138. Manual withdrawal of the pin enables the needle 2 to be moved independently of the driving means, but on restarting the machine the pin will snap back into position and the actuation of the needle 2 will be ensured.