GB824056A - A feeding mechanism, particularly for tube-stretching machines - Google Patents

Abstract

824,056. Rolling tubes. SINGER, F. July 18, 1957, No. 22832/57. Class 83 (4). Mechanism for feeding tubes to a metal working tool, such for example as in the machine described in Specification 686,867 for rolling tubes fed over a mandrel, in which two reciprocatory members, each of which carries a self-locking gripper, are arranged one behind the other and operate in tandem in alternate succession in such a manner that whilst one gripper grips the tube and advances it by a series of short feeding impulses, the other gripper releases the tube and returns to the starting position, is characterized in that the feeding impulses imparted by a reciprocating member carrying the tool are transmitted to the reciprocating gripper carriers by mechanical means and that the change-over in the transmission of the feeding impulses from one gripper carrier to the other is controlled by the movement of said gripper carriers themselves through the engagement or disengagement of clutches. A tube A to be stretched over a mandrel by a tool on a carrier 4 reciprocated longitudinally of the tube by crank means 2, 3, is fed in steps over the mandrel by self-locking grippers on carriers 27a, 27b reciprocated longitudinally of the tube. An extension piece 5 on the tool carrier 4 engages a cam 7 on a shaft 6 to oscillate, in conjunction with a spring 32, the shaft 6 and toothed sectors 8a, 8b secured thereto, an adjustable stop 30 engaging the sector 8a determining the stroke. The sectors 8a, 8b engage segments 12a, 12b on outer rings of one way clutches 11a, 11b, the inner rings of which are keyed to shafts 10a, 10b. The step by step rotation of the shafts 10a, 10b is transmitted by dog-tooth clutch members 13a, 13b, keyed to the shafts, to gears 21a, 21b loose on the shafts, which gears through further gearing 23a, 23b and racks 26a, 26b move the gripper carriers 27a, 27b in steps towards the tool carrier 4, the carriers being returned by motors 34a, 34b. In operation, for the gripper on the carrier 27a to feed the tube, a solenoid 19a (not shown), is energized to clutch in the gear 21a and a solenoid 19b is de-energized to move the dog-tooth clutch member 13b away from the gear 21b. The carrier 27a thus moves forward, feeding the tube. A contact arm 40a on the carrier 27a then engages a limit switch 37a, which energizes the solenoid 19b so that the carrier 27b now moves, and shortly after a limit switch 38a is engaged by the arm 40a to de-energize the solenoid 19a, so that the carrier 27b feeds alone. After a brief delay the switch 38a causes the motor 35a to move the carrier 27a back, a limit switch 39a stopping the motor. The carrier 27b is similarly operated.