GB1010467A - Improvements in or relating to looms - Google Patents

Abstract

1,010,467. Loom dobbies. RUTI MACHINERY WORKS Ltd. Sept 19, 1962 [Sept 26, 1961], No. 35744/62 Addition to 1,004,777 Heading D1E. In a positive single-lift open-shed dobby, the jack levers 116 are actuated by eccentric straps 20, the sheaves of the eccentrics being attached to sun wheels 125 around which planetary gears 133 are oscillated by a cam 139. Each planetary gear rolls idly on its sun wheel except when a gear 142 is locked against rotation, in which case the planetary gear turns the eccentric from one dead centre to the other to operate the jack lever. The gear 142 can be locked by a pin 149 entering a notch 148 in a locking plate 146, the pin being carried by a bell crank lever 152 which is rocked by a cam 156 during every cycle to lift the pin 149 clear of the locking plate 146. Engagement of the pin in a notch 148 is governed jointly by the pattern card and the position of the jack lever by means of a floating lever 170, the lower end of which is pivoted to the jack lever on a spring 171 and can thus occupy two positions corresponding to heald up and heald down; the upper end is linked to the pattern mechanism and can occupy two positions produced by the presence and absence of a hole in the card. The middle of the floating lever is linked to a block 166 sliding in a slot 158 in the bellcrank lever and also slidable in a vertical slot 167 in a fixed bracket. When the cam 156 rocks the bellcrank lever to lift the pin 149, the block 166 emerges from the slot 167 and can then be moved along the slot 158 by the floating lever 170. If the heald is to stay in the same position for the next pick, the upper end of the floating lever will be kept stationary by the pattern mechanism but the lower end will follow the previous movement of the jack lever 116 (the movement of which has been stored as a deflection of the spring 171); as a result, the block 116 comes out of register with the slot 167, so that when the bellcrank lever 152 is released by the cam 156, it is unable to turn owing to contact of the block 166 with the unslotted part of the bracket 168. A subsequent movement of the upper end of the floating lever 170 will change the position of the heald by bringing the block 166 into its mid-position where it can rise up the slot 167 and so allow the locking ping 149 to drop into a notch 148. Instead of providing horizontal and vertical slots 158, 167, the bellcrank lever 152 may have a notch in its upper edge, the block 166 being constrained to move horizontally so that the bellcrank lever can turn only when the block registers with the notch.