GB191218953A - Improvements in and relating to the Picking Motions of Looms. - Google Patents

Abstract

18,953. Yarbrough, J. E. Aug. 19. Picking-motions; pickers etc.; checking shuttles; beat-up motions.-Picking-mechanism comprises a cylinder in which a partial vacuum is created and a piston which is released at the proper moment to move under atmospheric pressure to effect the picking, the vacuum being created in such a manner that, when the loom is stopped, the lay tends to come to rest with the crank at or near the bottom centre and buffer devices being provided for checking the shuttle. In one arrangement, an horizontal cylinder 3 is mounted at each end of the lay and may have its open end closed by a cap 4 with perforations 5. The piston-rod 7 passes through a stuffing-box 8 and is connected to the upturned end 11 of an operating-bar 9, which slides in a groove in the bottom of the shuttle box. A picker, in the form of a buffer disk 17 formed to engage the shuttle tip, is secured to a rod slidably mounted within the hollow piston-rod and is normally held away from the end 11 by an adjustable spring within the piston-rod, so as to act as a check-buffer for the incoming shuttle. The rod 9 is actuated to create the vacuum by one end of a double lever 21, which is moved by pins 26 on a lever 23 connected by a link and a universal joint to a crank on the crank-shaft, the crank being so set relatively to the lay-operating crank that the vacuum is created as the lay crank moves from bottom centre. A latch 35 engages the lever 21 to hold the piston in the set position. During the next forward movement of the lay, absence of friction on the pins 26, the lever 21 being set, allows the lever 23 to be raised by pins on a spring- controlled disk engaging a cam-slot in the boss of the lever, so that a release dog 36, adjustably secured to the lever 23, is raised and acts on the latch 35 to release the piston and effect the picking, the piston being cushioned by air entering the cylinder through a by-pass controlled by a pin-valve 38. In another arrangement, a vertical cylinder under each shuttle box is moved to create a vacuum by a bell-crank lever and a crank on the counter or tappet shaft while the piston is held stationary by suitable link-work until a dog on the cylinder strikes a lever and moves a connecting-link past dead-centre position, whereupon the piston descends and through a connexion to a picking-stick shoe operates the picking-stick. The piston is cushioned by air entering through an opening which is adjustable in position and is provided with a flap valve. A similar cylinder-and-piston arrangement may be provided at the centre of the loom to operate simultaneously, through bell-crank levers and rods, arms carrying pickers in each box, the cylinder in this case being actuated from the crank-shaft.