GB860514A - Motor-driven shear device - Google Patents

Abstract

860,514. Shearing. MATTHEWS, S. E. (Georg, H.). Dec. 6, 1957, No. 38018/57. Class 83(4). In a shear in which an eccentric pin on a motor-driven shaft actuates a shear blade carrier, a cut is initiated by movement of a coupling-member to a position in which it transmits the motion of the eccentric pin to the shear blade carrier to effect a shearing stroke, the coupling member then being disengaged. Saturation of a lever 29 manually against spring- action or by a weight 45 when an electromagnet 43 is released lowers a spring-loaded catch 40 which engages a groove 31 in a shaft 9 journalled in the carrier 12 for the moving blade 13, and rotates the shaft 9 sufficiently for one of three arms 33 of the coupling-member 8 to be positioned in the path of the eccentric pin 7 as shown in Fig. 6. A motor 5 through friction gearing continuously rotates the eccentric pin 7 which engages the coupling member 8 and the work is severed. Springs 18 return the blade carrier 12 until the end of the shaft 9 engages a stop. On the next rotation the eccentric pin 7 engages the side of an arm 33 to move the coupling-member 8 until one of the recesses between the arms 33 faces the shaft 2 carrying the eccentric pin 2. In a modification, Fig. 11, upward movement of the blade carrier 12 is limited by engagement of a projection on the carrier 12 with a stop. The shaft 9 is provided with a triangular end 55 which engages a spring- loaded bar 56 to move the coupling-member 8 out of the path of the eccentric pin 7. As shown in Fig. 16, the shear is supplied with strip fed from a straightening-machine 74 through a channel-shaped guide 75 having a domed projection 76 up to a stop 70 adjustable along an angle-section guide 77. A switch associated with the stop 70 actuates the electromagnet 43 to cut the strip which in front of the shear bends up over the projection 76. Near the end of its stroke a projection 81 on the blade carrier 12 tilts the guide 77 to remove the severed length. In a further modification, the stop is mounted at a fixed distance from the shear which runs on guides longitudinally of the work. The shear is moved with the work by the work engaging the stop and is actuated by a switch associated with the stop.