GB682784A - Improvements relating to feed control mechanism for heading machines - Google Patents

Abstract

682,784. Forging-machines. WIRE FORGING MACHINES, Ltd. Feb. 6, 1951 [Dec. 22, 1949], No. 32819/49. Class 83 (iv). [Also in Group XXIV] Feed mechanism.-A feed control mechanism for heading machines comprises a connecting rod associated with an intermittent one-way feeding mechanism, a member slidably mounted relatively to said connecting rod, means for reciprocating said slidable member and locking means on said connecting rod for normally locking the rod to the slidable member and displaceable means for breaking the lock between the rod and the slidable member automatically so that the slidable member con tinues to reciprocate without reciprocating the connecting rod and thereby occasions a stoppage of the feed without necessarily stopping the driving means. Fixed on one end of the driving shaft 10 of a heading machine is a crank 11 and crank-pin 12 to which is connected an adjustable strut 13 the other end of which is connected to an oscillating lever 14 fulcrumed on the base of the machine. The upper end of the lever has a block 15 slidably mounted in a slot 171 in a rod 17 connected to a pawl-carrying arm 18 mounted on a feed shaft 19 carrying a ratchet wheel 20 which is bolted to a pinion 22 (Fig. 6). Bolted to the arm 18 is a clutch housing 23 having internal splines 231 for engaging clutch plates 24 and clutch plates 25 are splined on the shaft 19. The plates cooperate with friction blocks 26 which are maintained in frictional contact with the plates by springs 27 the tension being adjusted by a nut 191. The clutch counters any tendency for a feeding movement to be imparted to the rod 17 which may occur due to friction between the block 15 and the sides of the slot 171. The block 15 has a cylindrical outwardlydirected projection 151 formed with a quadrantal "notch" 152. Pivotally mounted on the rod 17 is a trigger lever 28 the arm 281 of which has a tooth 282 for engaging the notch 152. The other arm 283 of the lever cooperates with a hollow cylindrical plunger 29 (Fig. 4), slidably mounted in a casing 30 fixed to the machine case. Within the plunger 29 is a spring 31 engaging a push rod 32 slidable in the plunger said push rod having a knob 33 slidable within the casing 30 in a sleeve 331. The sleeve has a recess 332 which co-operates with a spring-loaded ball 36 for maintaining the rod 32 in an inwardly pressed position. Pivoted to the trigger arm 283 is a rod 37 the free end of which slides in a guide 172 and a spring 38 around the rod urges the tooth 282 on the trigger arm 281 into engagement with the notch 152. In operation, when the tooth of the trigger lever is in engagement with the notch the driving shaft oscillates the lever 14 which reciprocates the rod 17 which in turn rotates the feed shaft 19 step by step through the ratchet mechanism. To stop the feed the knob 33 is pressed inwardly the spring 31 being stressed so that when the arm 283 of the trigger lever moves clear of the plunger 29 during its forward stroke the plunger shoots into the path of the arm. On the rearward stroke of the rod 17 the arm 283 contacts the plunger and the trigger lever is turned so as to disengage the tooth 152 from the notched slide block 15 so that, thereafter, oscillation of the lever 14 merely occasions a sliding of the block 15 in the slot 171.