GB525193A - Improvements relating to winding or reeling mechanism suitable for use with metal extrusion and other machines delivering long lengths of material - Google Patents

Abstract

525,193. Winding or reeling lead pipes &c. HENLEY EXTRUSION MACHINE CO., Ltd., DUNSHEATH, P., and GRIFFITHS, F. T. Feb. 18, 1939, No. 2592. [Class 120 (ii)] [Also in Groups XVI, XXII and XXX] The speed of the takeup reel of a metal extrusion or other machine is controlled to give a constant linear speed of take-up by the movement of a pulley with which the material being wound or reeled engages as it passes to the reel, the device for correcting the speed of the reel being brought into operation only when the pulley is travelling, in one direction or the other, outwardly from a mean position and is not less than a predetermined distance in the direction of travel from that position and being thrown out of operation at the commencement of the return movement of the pulley towards the mean position. As shown the pulley 14, over which the material passes on its way to the take-up reel, is journalled on a stud in a crosshead 7 slidingly mounted between channel irons 6 of a vertical frame 1 and the weight of the pulley and cross-head is counterbalanced by a weight 15 coupled to the cross-head by a rope 16 passing over a pulley 17 at the top of the frame; a detachable pad on the back of the crosshead is so adjusted that the cross-head has a slight tendency to fall. A pulley 25 is mounted at the top of the frame at each side of the pulley 17 and a cord 30 passing over the pulley carries a weight 31 at one end and a counterweight 32 at the other and a projection on the cross-head engages the underside of the weight 31 at one side of the frame when the cross-head moves up and another projection the top of the weight 31 at the other side of the frame when the crosshead moves down. Each pulley 25 is mounted on a shaft 26 carried in ball-bearings and having a friction disc 40 at its end opposite to that carrying the pulley and engaging a disc on a bush 44 rotatable on a spindle 42; the bush 44 is pressed by a spring 45 against the disc 40 and carries a mercury switch 48 on a platform 47 and when the cross-head moves a predetermined distance past its mean position in the upward direction the weight 31 is lifted and the pulley 25 is rotated. Rotation of the pulley drives the bush 44 until it engages one of two adjustable stops 50 and the switch 48 is tilted to start a pilot motor which reduces the speed of the reel by altering the setting of a valve if the wheel is hydraulically driven, of a speed regulator if the wheel is electrically driven or of gear ratio regulator where a variable speed gearis employed. When the speed of the reel has been reduced sufficiently, the cross-head slowly descends, the switch 48 returns to normal and stops the pilot motor and downward movement of the cross-head beyond its mean position pushes down the other weight 31 and causes the other switch 48 to start the pilot motor in the reverse direction to accelerate the take-up reel. Movement of the cross-head is limited by stops 37, 39 on the channel irons 6 and with the arrangement shown the predetermined distance of the crosshead pulley from the mean position is a minimum : by moving these stops apart, the predetermined distance may be increased when a wider divergence between the speeds of delivery and take-up is permissible before the speed-correcting device is brought into operation.