Patent GB-1108677-A (GB)
Title: Rotary shears
Inventor: TSELIKOV ALEXANDR IVANOVICH
IPC: B23D25/12
Filed: 1965-08-17
Abstract: 1,108,677. Flying shears. VSESOJUZNY NAUCHNO - ISSLEDOVATELSKY I PROEKTNO - KONSTRUKTORSKY INSTITUT METALLURGICHESKOGO MASHINOSTROENIYA. 17 Aug., 1965, No. 35162/65. Heading B3W. In a roller cutter flying shear a miss-cut mechanism is provided which operates by imposing a secondary rotation on the blade carriers, each blade being mounted on a rotatable shaft mounted in a rotatable gear housing, the shafts being rotatable by means of a hinge and lever arrangement controlled by a crank-shaft and the gear housings being rotatable by means of a driving shaft, the driving shaft and crank-shaft being interconnected by a gear system such that rotation of the driving shaft is able to cause rotation of the crank-shaft, the crank-shaft being also lockable such that when the crankshaft is locked rotation of the driving shaft does not cause rotation of the crank-shaft. The shear comprises a drive motor 32 connected by a dog clutch 33 and gears 30 and 29 to a main drive shaft 27. The shaft 27 is connected by a second dog clutch 26 to a hollow shaft 23 on which is mounted a gear 21 which meshes with a similar gear 22 mounted on a hollow shaft 24. Each of the hollow shafts is supported in bearings in the shear frame 25. Secured to the shaft 23 is a gear housing 1 and secured to the shaft 24 is a gear housing 2. The gear housings contain similar epicyclic gear mechanisms, only that in the lower housing 1 will be described. A shaft 6 is mounted in bearings in the hollow shaft 23 and carries a gear-wheel 3 which meshes with an idler wheel 4 which in turn meshes with a gear-wheel 5. The idler wheel 4 is mounted on a shaft 7 supported in bearings in the gear housing 1. The gear-wheel is mounted on a shaft 8 which is supported in bearings in the housing I and which also has mounted thereon a cutter head 15. A cutter blade 16 is secured in the cutter head by a wedge 19. The shaft 6 projects through the hollow shaft 23 and is secured to the mid-point 39 of a bell-crank 37, 38. A link 36 connects the arm 37 of the bell crank to a lever 34 which is mounted on the projecting end of the shaft 12 which corresponds to the shaft 6. The arm 38 of the bell crank is connected by a resilient tie-rod 40-44 to the crank-pin 45 of a crank 46 which is mounted on a shaft 47. The shaft 47 is connected by a dog clutch 48 to a shaft 49. Freely rotatable on the shaft 49 is a gear 50 which is driven through gears 28, 63 and 64 from the main drive shaft 27. A block 52 which has teeth at each end slides on a splined section of the shaft 49 and can be moved by a fluid cylinder 61 to engage either a non-rotatable locking ring 62 or internal teeth in the gear 50. Operation.-With the block 52 in engagement with the locking ring 62 the blades are carried round by the gear housings 1 and 2 and the work-material is cut at each revolution of the housings. Miss-cut operation.-With the block 52 moved into engagement with the gear 50 the shafts 49 and 47 are driven at a speed determined by the ratio of the gears 28, 63, 64, 50. If this ratio is for example 1: 2 then when the gear housings 1 and 2 have made a complete revolution the crank 46 has made only half a revolution and the cutter heads 15 and 17 have been rotated to a position where the cutters do not co-operate. Cutting short lengths.-The shear can also be run at a speed such that the peripheral speed of the cutters exceeds the speed of the workmaterial by about 20%, since excessive loads on the cutter driving mechanism are accommodated by the resilient tie-rod 40-44. The strength of the spring in this assembly is such that during normal cutting operations the spring does not deflect.