Patent GB-800435-A (GB)
Title: Improvements in or relating to take-up or tension devices for knitting machines
IPC: D04B15/88
Filed: 1955-10-27
Abstract: 800,435. Knitting-machines. SCOTT & WILLIAMS, Inc. Oct.27, 1955, No. 30816/55. Class 74(2). Take down mechanism for a circular machine adapted to knit stockings each of which is pressed off when completed, comprises two pivoted arms 163 mounted in a body 147 adapted to be raised within a tube 45, concentric with and extending upwardly within the needle cylinder, by a pneumatically operated piston 145, Fig. 21, so as to position the arms adjacent the welt W of a freshly commenced stocking. When this piston is allowed to fall by the removal of the air pressure, the arms 163 grip the welt W and under their weight and the weight of the body 147 exists a pull on the fabric to effect take down. On completion of the stocking the body falls causing the arms to release their grip on the welt and the stocking is sucked into a storage container. As shown in Fig. 21 the arms 163 have their upper ends splayed outwardly to direct the welt portion to a position between the arms as it is formed. Each arm also carries a rubber pad 169 and these pads grip the welt when the arms move towards each other. The lower ends of the arms beneath the pivots 164 extend within the body portion 147. Between the lower portions of the arms is positioned a ball 151 from which extends a bolt 150 surrounded by a spring 159 which urges the ball downwardly to spread the lower ends of the arms 163 apart and to close the upper ends to grip the welt. The tube 45 is normally rotated synchronously with the needle cylinder but during the period when air is admitted at the lower end to raise piston 145 the tube is held stationary. Accordingly, during the knitting of the welt, air is admitted under pressure to the lower end of the tube 45 to lift the piston 145 which engages the lower end of bolt 150 to raise the body 147 and arms 163. At the upper end of the tube the body 147 engages a projecting ring 49, Fig. 21, to prevent its further movement such that the piston compresses the spring 159 and moves the ball 151 upwardly to spread the upper ends of the arms 163 apart. The welt as it is knitted is then guided between the arms and when sufficient has been completed, the air supply is cut off allowing the piston 145 to drop to the bottom of the tube. The spring 159 then urges the ball 151 downwardly to close the arms 163 so that they grip the welt and remain suspended with the body 147 to urge the stocking downwardly. The drive to the tube is reconnected and it continues to rotate with the needle cylinder. Towards the completion of the stocking, the tube 45 is again held stationary and this time with one opening 250, Fig. 6, in alignment with a discharge tube 249 which is connected to a storage container having a vacuum motor associated with it to create a suction through the tube 249. On completion of the stocking it is pressed off the needles permitting the body 147 and arms 163 to drop to the bottom of the tube where the bolt 150 rests upon the piston. The toe end of the stocking is drawn into the discharge tube 249. A stop member 176, Fig. 28, is then projected into the lower end of the tube above the body 147 and air under pressure is again admitted to the lower end of the tube 45 to raise the piston 145 and body 147. Upon engagement of the stop member 176 by the body 147 to stop its upward movement, the spring 159 is again compressed and the ball 151 raised to open the arms 163 to release the stocking which is thereupon drawn into the storage container through discharge tube 249. The valve controlling the air supply to the tube 45, the mechanism controlling the rotation of the tube 45, the insertion and withdrawal of the stop member 176 and the switch controlling the vacuum motor are each controlled from the main pattern drum. In an alternative arrangement, Fig. 29, and where an elastic welt is knitted the take-down arms are replaced by a disc 284 adapted to be raised and lowered away from and into engagement with the ends of rods 286 carried by a body 281 so as to permit the welt to enter between the disc and rods and subsequently gripped when the disc is lowered. Reference has been directed by the Comptroller to Specification 753,213.