Patent GB-171483-A (GB)
Title: Improvements in or relating to circular knitting machines
IPC: D04B9/10
Filed: 1920-08-17
Abstract: 171,483. Bentley, P. A., and Goddard, J. W., (trading ns Bentley Engineering Co.)., and Bentley, P. A. Aug. 17, 1920. Circular machines.-Relates to machines with two coaxial needle cylinders and doubleended latch needles, as decribed in Specification 15008/00. The cylinders are rotated or reciprocated within stationary cam boxes as described in Specification 24290/12. The invention comprises driving- mechanism whereby two forward speeds and a reciprocating motion are obtained by means of sliding clutches controlled by a pattern drum, means for imparting a lead to the threadguide in respect to the central stitch cam, means for operating improved needle picking devices and transfer cams, and meams for automatically varving in the course of the knitting the length of loop drawn by the stitch cam. Direct drive of the cylinders is effected from a pulley 21, Fig. 3, having a sleeve 22 normally in engagement with a clutch member 23 splined un the shaft 1. The geared drive is obtained through a pinion on the sleeve 22 which engages a pinion 25 on a secondary shaft 27 which is normally idle. Another pinion 26 on the shaft 27 engages a pinion 28, which is also engaged by a clutch 24 splined on the shaft 1. The pinions 25, 26 are normally free of each other, but when the, direct drive is to be replaced by the geared drive, the clutch 23 is shifted by means of a lever 31 controlled bv a pattern drum 30, and the lever 31 also shifts a plate. 32 which brings the pinions 25, 26 into engagement, and allows the pulley 21 to drive the shaft 1 through the pinions 25, 26, 28 and the clutch 24. When the change, to reciprocation is to be made, the clutch 24 is moved by pattern-drum lever 35 to engage a pinion 4 and disengage the pinion 28. A continuously-acting change-motion train of known type, comprising a gear-wheel 8 meshing with the pinion 25, a crank-shaft 7, and crank 6, and a quadrant gear 3 then drives the pinion 4 and oscillates the shaft 1. The. knitting-cams comprise a central stitch cam 35, Fig. 13, mounted with up-throw cams 37, 38 on a portion 36 of the cam shell 13, which slides vertically under control of a lever 42 operated by a control disc or drum 43. The thread guide 44, Fig. 6, is carried on a circumferentially sliding segmental plate or band 46, and is locked in the two extreme positions shown in full and dotted lines according to the direction in which the cylinders are turning; by means of a catch 48. Fig. 7. which projects through an horizontal slot 47 of the cam-shell 13, and is operated by pins 52, 53 and a pattern lever 54. In ordinary round-and-round knitting, the catch 48 is housed in a shallow niche 49 of the slot 47, but at the first reversal of reciprocating knitting the catch travels to a deeper niche 51 at the other end of the slot, carrying the threadguide 44 along with it to the new position. To enable this to be done, a plate 55 moving with the needle-cylinders is adapted to engage the catch 48 when thrust in by the pin 52 by means of the cam-edge 56 or 57, thus withdrawing it from the niches 49 or 51 and causing the thread-guide 44 to travel from one position to the other. The widening picker 58, Fig. 10, consists of a radiallydisposed arm pivoted on a spring-controlled vertically slidable post 59 carried by the end of a bellcrank lever 61, the lower end 60 of which is operated at the required times by an incline 62 on the control disc 43, thus bringing the bellcrank lever 61 into the position shown in full lines. A truck 64 on the driving-wheel 2 then engages the shaped end 63 at each revolution to lift the widening picker at the end of each stroke into engagement with the inactive needles. The post 59 carries an angle-piece 66 extending over the picker 58 and embraced by a pair of spring arms 69, 70 pivoted. to a bracket. When the post 59 is raised, the arms 69, 70 come in contact with the picker 58, holding it in readiness to engage the first inactive needle presented. When this occurs, the picker 58 is rocked sideways, and trips the arms 69, 70, the post 59 being depressed by a spring 59<a> to the inactive position shown in Fig. 10. The transfer cams consist of spring- controlled inclined bolts 72, 73, 78, 79, Fig, 8, operated by levers 82, 83, 81, 84 respectively from a control disc 80, and cams on which operate blocks 87, 91 on rods 86, 90. The upper ends of these rods carry blocks 85, 89 which bear on the free ends of the levers 81 - - 84. In transferring needles from the bottom cylinder to the top, the cam 85 is rocked by a high cam on the disc 80 to actuate both levers 81, 82, thereby placing both cams 72, 78 in action, while a similar cam places the cam 79 in action. For transferring needles from the top cylinder, the cams 73, 79 are placed in action to depress the top cylinder sliders, and the cam 85 is operated by a low cam on the disc 80, thereby operating the lever 81 only, the lower sliders thus rising on the cam 78 while the cam 72 is out of action. The lower ends of the rods 86, 90 are provided with projections 93, 94 which, when the rods are in the elevated position, are engaged by cams 95, 96 which restore the rods and levers 81 - - 84 to machine position after a transfer operation.