Patent GB-1219181-A (GB)
Title: High-velocity shearing machine
Inventor: BRAMLEY HAL FRANCIS
IPC: B23D21/00
Filed: 1968-01-31
Abstract: 1,219,181. Shearing. AMSTED INDUSTRIES Inc. 31 Jan., 1968 [27 Feb., 1967], No. 5054/68. Heading B3W.  A high velocity shearing machine comprises dies 62 and 86, a piston and cylinder unit 60 which is connectible to a source of gas under high pressure, the piston 100 including a stop shoulder 104 engageable with a resilient pad 116  to limit its shearing stroke and a plunger 106 extending from the shoulder which strikes the die 86 to shear wire or rod stock 12, push rods 122 which return the piston to its initial position after a shear stroke and a latch slide 140 which retains it in that position. Stock 12 is fed by rolls (16), Fig. 1 (not shown), from a wire drawer (14) through the fixed die 62 and movable die 86. The die 62 comprises a clamp 63 actuated by a fluid-operated piston and cylinder unit 78, 64 under the control of a cam-shaft 66 driven from a main cam-shaft 38, Fig. 3. Adjusting screws 84 hold the fixed die 62 in shearing relation with the movable die 86 which is supported by a pin 92 urged by a spring (97) (Fig. 4, not shown) to hold the die in alignment with the die 62 and lowered through linkage 93-95 by a cam 42 on the cam-shaft 38. A switch (98) operated by lever 94 checks whether the die is in its raised position. The push rods 122 are raised against the action of springs 126 by a cam 40 on the cam-shaft 38. The latch slide 140 is moved into the path of the plunger 106 against the action of springs 148 by means of a cam 146 on cam-shaft 66. The slide may be locked in latching position manually by means of a pin 150 (Fig. 3) which in the locking position actuates a signal light and may automatically switch off the machine. During normal operation of the machine, the slide is locked in latching position by a dog 158 spring-urged into the path of the slide, the dog being raised by a release solenoid 68. A gauging stop 180, Fig. 6, is mounted through slides 182, 184 on a member 164 slidable between guides 167 on the machine table 20. The stop is raised by a piston and cylinder unit 174. A probe pin 196 urged by springs to project slightly from the stop face 81 actuates a switch (204) (Fig. 10, not shown) when the stock abuts the face 181. Non-actuation of the switch may actuate a cut-out relay. A chamber 58 associated with the main cylinder unit 60 is connected to a source of highpressure gas. A single other source supplies all other pressure requirements, i.e. an air-operated clutch 30 associated with the main drive shaft 22, the stock clamp cylinder 64 and the gauging stop control cylinder 174 through solenoidoperated valves. In operation, with the stop 180 in engagement with the stock, the clamp 63 is moved to clamp the stock in die 62. The stop 180 is then raised out of engagement with the stock. Meanwhile through cam 40 the push rods 122 have been lowered, leaving the piston 100 supported by the latch slide 140, and the pin 92 has been lowered through cam 42, leaving the die 86 supported by the stock. The latch slide 140 is then released by cam 146 and retracted by spring 148. The piston is driven downwards striking the die 86 and shearing a workpiece 90 from the stock. Excess energy of the piston is absorbed by pad 116 and excess energy of the die 86 by a resilient mounting 161. The stock is immediately unclamped, the push rods raise the piston and the die 86 is re-aligned with the die 62. Another length of wire is drawn in machine 14 and fed to the shear if the die 86 is in its raised position; otherwise the operation of the machine is stopped. The latch slide 140 is moved into latching position. In an alternative embodiment (Figs. 14-16, not shown), the die supporting the stock length to be cut off is fixed and the clamp 63 associated with the fixed die is omitted. The gauging stop 180 does not need to be raised before the sheath stroke. The pressure chamber and main cylinder unit can be replaced by others of different capacities.