678,174. Pirn winding machines. WILDT & CO., Ltd. Aug. 30, 1950 [Aug. 30, 1949], No, 22525/49. Classes 120(ii) and 120(iii) An automatic pirn winding machine of the kind comprising a winding spindle driving the pirn to be wound by means of a driving centre, an outer centre, a carriage for withdrawing the driving centre and the outer centre to the starting position and a feed nut or screw for advancing the carriage during winding, is provided with a single driving motor coupled by differential gearing to drive, in turn, the winding mechanism and the pirn-changing mechanism. The machine is driven by a single reversible electric motor 5, driving a shaft 7 which, through an epicyclic train and differential gear unit 9 drives the shaft 12 or a casing 14. The shaft 12, through a flexible coupling 13, drives a shaft 17 and hence, through belt and pulleys, the winding unit, the casing 14, furnished with left- and right-hand worm threads 15, 16, drives, selectively, a worm 19 mounted upon and driving a square-sectioned shaft 20 whereon is mounted the cams for effecting doffing and donning, during which operations a brake 26 contacts a drum 27 on shaft 12 to prevent it from turning. This arrangement permits the winding spindle to be driven in either direction, but by sliding the casing 6 to engage either of the worms 15 or 16 with the wheel 19, the doffing and donning mechanism is always driven in the same direction, the sliding of the casing 6 automatically reversing the motor connections. When winding is in progress, the doffiing and donning unit is positively held against rotation by a stop engaging a ledge on the wheel 19 which is released, when the winding of a pirn is complete, by the pirn-carrying carriage coming into contact with a lever 31. Movement of the lever 31 brings the brake 26 into contact with the drum 27 and the single-revolution shaft 20 is set in motion. The worm wheel 19 driving the shaft 20 is formed bv a rim sandwiched between discs 37 spring-pressed together at 38 to constitute a " slipping clutch " which will limit the torque, applied to the shaft 20. The rotation of the shaft 20 effects the following operations: - (i) The spring- urged thread-guide lever 41, which is oscillated about a pivot in a bracket 43 under the influence of a cam and telescopic hub 46, is moved to a rearward position bring- ing the thread-guide over the pirn-driving centre. This is effected by a cam 48 and lever 47. (ii) A cam 52, through a lever 55 and a flexible cable 56, moves a two-lift cam, pivoted on the tailstock 57 of the winding unit, to release the feed unit from the feed screw and later, to withdraw the tailstock quill. A tappet adjustment is fitted and also a knob 59 to allow for manual operation, (iii) A drum 65, through a flexible steel tape 64 anchored to the tailstock body, withdraws the pirn-supporting carriage from the winding box and brings it against a limit stop. The drive between the wheel 19 and the drum 65 is through a spring-pressed roller 70 in a slide attached to the wheel 19, the drum 65 being provided with a cam-like projection, which may be the head 69 of the screw 68 anchoring the steel tape 64 to the drum, over which the roller moves, when the carriage meets its limit stop, to stop the drive to the drum 65. (iv) A cam 73 through a flexible cable 74, moves the thread collector arm 71, pivoted at 76, to take the yarn leading from supply to the wound pirn and draw it into a loop, a cutter on the arm 71 severing the loop on the side near the pirn to free the same. (v) Simultaneously with the above operation, from the same cam and through a further flexible cable, a magazine 83 is indexed to supply an empty pirn to the loading device 100. The magazine 83 comprises a wide chain-like device consisting of links 95 and wires 94 carrying endless tapes 96, festooned between the wires, to provide pockets for the pirns. A flexible cable 81 operates a ratchet arrangement to index the wheel 89 and advance the links 95 over the sprockets 86, 87. The end plate 97 is adjustable to suit empty pirns of different lengths. (vi) From the pockets of the magazine, the pirns fall one by one, into troughs 100 of the loading device being adjustably guided therein by members 99. The troughs 100 are carried by spring- biassed arms 102 on a spring-urged frame 101 rocked by a cam 103 through a rod 108. A wire guide 110 fixed to the loading device operates to guide the yarn from supply across the driving face of the inner centre so that it is trapped between it and the new pirn before the start of a winding operation. In a modification, Fig. 18, the magazine has capacity for only a small number of pirns, say three, which are moved upwardly, step by step, on to a number of saw tooth-like ledges on a rack 111 by a slide 112. At each end of the magazine, spring-grippers 115, carried by slides movable vertically in pillars 114, engage the pirns to feed them upwardly. The slides are operated by a flexible cable from the cam 103. In this magazine arrangement, the loading arm 125 is furnished with spring clips 126 into which the pirns are thrust. A further severing device may be fitted to cut, when winding commences, the tail of yarn still remaining attached to the loop trapped under the head of the pirn. Specification 617,895 is referred to.