Patent GB-1072391-A (GB)
Title: Flying shear
Inventor: COOKSON WILLIAM
IPC: B23D25/04
Filed: 1963-02-18
Abstract: 1,072,391. Flying shears. COOKSON SHEET METAL DEVELOPMENTS Ltd. Jan. 31, 1964 [Feb. 18, 1963], No. 6539/63. Heading B3W. In a flying shear the flying movement of the blades is derived from the forward movement of the material and the blades are caused to close together and open again during the forward movement by cam means. The apparatus described is suitable for dividing a corrugated sheet and comprises a shear 21 mounted on a carriage 23 which rolls on rails 25. A bridge 29 surrounds the rails and supports a pair of parallel blocks (34, 35), Fig. 2 (not shown). In the block 34 is a cam track 37, the vertical base of the track leads out to a flat protuberance 39 and the block (35) has a horizontal surface (43) provided with a cam rail (45) a portion of which forms a spring-loaded rail latch (49) and an end cam (47). The top platen 51 of the shear has a cam block 53 secured to each end and each block supports a cam rod 55 which is free to rotate and slide axially in the block. A rail 59 joining the rails 25 supports a spring-loaded latch 61 which engages a spring-loaded plunger 67 secured to the carriage 23. Projecting from the front face of the carriage are two rods (76) on which slide blocks (74) secured to a rail 73, which together with side rails 71, form a run-out table (69). A stop rail 81 is fastened to the run-out table, which also carries a cam block (77). Springs (75) connect the carriage 23 and the run-out table 69 and their relative movement is limited by a positive stop. A return table 87 runs on rollers 89 in the side rails 71 and is attached by a cable 111 to the carriage 23. The return table carries a stop rail 91 mounted on rods 92 which are connected by a crossmember 97 carries pins which engage the sloping faces 105 of a pair of cam blocks 103 which are secured to the rails 25. A gripping device 113 is secured to an extension 115 of the carriage 23 and comprises a pair of arms (117), Fig. 5 (not shown) pivoted on a pin (119) which is supported by brackets (121). A cross rail 125 connects the rails 25 and supports a cam arm 127 having a cylindrical end 129 which is pivoted on a pin at its base and acted on by a spring 131. When the cylindrical end 129 passes between the arms of the gripping device 113 they are forced outwards and grip a rib 18 of the material 17. Operation.-Sheet metal material 17 leaving the last roll stand 11 of a mill passes between the shear blades 31 and 33 and is shown in Fig. 1 as about to strike the stop-rail 81. Carriage 23 cannot move as it is locked by the plunger 67 which is pressed down by the cam block 77, but the run-out table 69 moves forward on the rods (76) against the tension of the springs 75. This action moves the cam block 77 off the plunger 67 which unlocks the carriage 23 and moves it forward as soon as the run-out table has completed its limited movement relative to the carriage. As the carriage moves forward the cam rod 55 which is engaged with the cam track 37 moves the shear blade 31 downwards to cut the material. Just prior to the cut being made the cylindrical end 129 passes between the arms (117) so that they grip the material and move it at the same speed as the carriage. The blade 31 is raised by the latter part of the cam track 37 and at this point the cylindrical end 129 passes out from between the arms (117) and releases the rib (18). As the carriage moves forward the return table 87 is pulled rearwards by the cable 111 and the stop rail 91 moves upwards into the path of the freshly cut end of the material 17. When the rail 91 is engaged by the material the return table 87 is moved forward and through the cable 111 draws the carriage 23 back to its starting position. As the arms (117) pass over the cylindrical end 129 the cam arm (127 pivots on its mounting pin so that the gripper is not operated on the return movement of the carriage. During this return movement the end (57) of the rod 55 is engaged by the guide rail (45) and holds the rod out of engagement with the cam track 37 so that the blade 31 is not operated during the return movement of the carriage 23. At the end of the return movement the end (57) leaves the guide rail and engages the cam block (47) which moves the other end of the cam rod 55 into engagement with the cam track 37.