Patent GB-636760-A (GB)
Title: Improvements in or relating to the mechanical doffing of ring spinning and like frames
Filed: 1947-07-16
Abstract: 636,760. Doffing apparatus for textile machines. BRITISH COTTON INDUSTRY RESEARCH ASSOCIATION, GREGORY, J., FOSTER, G. A. R., and CATLING, H. July 16, 1947, No. 18899. [Classes 120 (ii) and 120 (iii)] [Also in Groups XXVI and XXX] Doffing apparatus of the kind comprising doffing mechanism on a carriage movable to predetermined positions along a textile spinning or similar frame or mule and latching mechanism for locating and securing the carriage has means for stopping the doffing mechanism on completion of a doffing cycle and for releasing the latching mechanism, thereupon to initiate movement of the carriage to the next latching position, whereat the carriage drive is stopped and the doffing mechanism restarted. The carriage preferably is driven at high speed until the next latching position is almost reached and then at slow speed. When a line.of spindles has been doffed, the carriage may reverse at high speed to the starting position. The invention is described with reference to the carriage doffer disclosed in Specifications 597,887 and 628,672 in which a small group of spindles, say twelve, is doffed and then the carriage moves forward to another group. A bar positioned along the front of the spinning or similar frame has pegs for locating the carriage - in front of the groups of spindles. In the preferred embodiment of the invention, one electric motor is employed to drive the carriage and doffing mechanism and is connected by a friction clutch to the doffing mechanism in a manner similar to that described in Specification 628,672. The drive to the carriage is by a chain 50 to a transport drive shaft 49, to which are fixed a high speed sprocket 54, a slow speed sprocket 55 and a reversing gear driving pinion 56, the latter engaging a' second pinion 57, to which is attached a reverse gear sprocket 58. Sprockets 54, 55, 58 drive sprockets 65, 66, 64 on a threespeed shaft 60 through chains 62, 63, 61 and a chain 92 transmits motion from shaft 60 to a lay shaft 94, which carries a spring-loaded clutch member 99 normally in engagement with another clutch member 102, to which a pinion 103 is secured. The pinion 103 engages a reduction gear wheel 105, which transfers the drive through a shaft 106 to a driving wheel 107. The spring- loaded clutch member 99, can be disengaged manually by a shoe 108 operated upon by a Bowden cable 110. Driving wheel 107 is a road wheel of the doffer carriage and runs on a special lower rail O fitted to the spinning or similar frame. After a doffing cycle, the carriage moves along the rail O to the right in Fig. 1 in high speed gear until a lower latch element 10 strikes a peg P on another rail O<SP>1</SP> of the frame. The carriage continues to move and the element 10 is moved back relative to it, carrying with it a sliding member 8, to which the element 10 is pivoted. The lower face 29 of the sliding member 8 strikes a cam bowl 28 and lowers a lever 27, causing a shaft 21 to rotate to raise levers 25, 76 and levers 26, 31, 33, 35 to disengage a high speed clutch and engage a low speed clutch on shaft 60 respectively. The carriage then moves in slow speed gear until the lower face 1a of an upper latch element 1 is above the peg P and a bowl 6 is over a sloping face 7a of the sliding member 8. When a notch 2 in the upper latch -element 1 reaches the peg P, the element 1 drops to locate the carriage and a shaft 3 is turned to lower levers 31, 33, 35 to disengage the slow speed clutch and cut-off the carriage drive. Simultaneously, a link 48 is lowered to engage the clutch members which drive the doffing mechanism. As the doffing cycle approaches completion, a cam 125 on the cam shaft X of the doffing mechanism depresses a bowl 123 to raise the opposite end of a lever 122 on which it is carried. Due to the sliding movement of the member 8, a bowl 12 connected to the lower latch element 10 is located at this stage above the end of the lever 122 and is raised by it to release the element 10 from the peg P, whereupon a spring A pulls the sliding member 8 to the right, cam bowl 6 moves up the sloping surface 7a and upper latch element 1 is moved off the peg P. At the same time, cam bowl 28 ceases to be in contact with the face 29 and the various levers associated with shaft 21 are re-set. The unlatching of the element 1 turns shaft 3 and re-engages the high speed gear and the carriage moves off to the next group of spindles. During the movement of the carriage towards the last peg P on the rail 01 and after the high speed gear has been disengaged for the last time, a cam bowl 116 makes contact with a fixed cam on the machine frame and, through lever 114, brings a pin 25a on lever 25 opposite a notch 75a in a lever 75. On the sliding member 8 moving to the right at the completion of the last doffing cycle, lever 25 is raised, raising lever 75 to bring the reversing gear into operation, whereupon the carriage moves back along the rail O to its starting point. On reaching the starting point, according to the Provisional Specification, another cam on the machine engages a lever on the carriage to stop the motor. For convenience in moving the carriage on and off the end of the machine by hand, the clutch member 99 can be disengaged by a hand control on the Bowden cable 110. The cable for the electric motor is unwound from a drum on the carriage during the forward run by the pull of the cable, but during the reverse run it is wound back on the drum at a speed slightly in excess of the speed of the carriage by a slipping clutch and free-wheel arrangement driven by one of the road wheels of the carriage (see Group XXX).