Patent GB-1046297-A (GB)
Title: Straightening machine
IPC: B21D53/88
Filed: 1964-05-15
Abstract: 1,046,297. Straightening. G. A. E. COUTURE. May 15, 1964 [July 22, 1963], No. 20364/64. Headings B3E and B3H. A straightening machine, e.g. for straightening blades, spring leaves and shafts, comprises a continuously reciprocating hammer movable between first and second positions in which the hammer cannot and can strike respectively a workpiece located at a station, and sensing means responsive to deviations from a desired shape of the workpiece adapted to control the hammer from one position to the other. The machine comprises a conveyer system having pairs of support rollers 22, which act as anvils and spring-loaded rollers 24 driven by a motor 30 via a pneumatic clutch 34 and a chain-andsprocket assembly 26, a diaphragm-type brake 40 on the shaft 42 to positively stop the rollers 24, a contact plate 44 insulated from the frame and table 10, 12 and a hammer assembly 16 supported on columns 52 above the table. The assembly comprises a motor 58 driven hammer 54 vertically reciprocated via an eccentric 62 on a shaft 60 co-operating with a block 64 laterally slidable in a box 46 from which depends a collar 70, housing the non-rotatable hammer 54 in which is housed a gear 74 threadedly attached to the upper end of the hammer to secure it to the box and which is rotated to lower the hammer relative to the box by a rack 78 driven in one direction via a gear 80 and in the other by a pneumatic cylinder 116 and pneumatic clutch 82 connected to a ratchet assembly 84. The ratchet 84 is connected via a ball-and-socket joint 88 to a crank arm 90 of an eccentric 92 on the shaft 60 and rotates the gear in a direction " A." A contact breaker 110 for use in the control circuit comprises a shaft 132 bolted to the pulley 59a so that it rotates therewith and with the hammer drive shaft 60, an inner rotatable timing range 136 mounted on bearing 134 and releasably locked to the sleeve 138 rigidly secured to the frame 10, a cam follower 144 mounted on the ring 136 and a cam 146 keyed to the shaft 132 which has a dwell 150 increasing in angular span from one end to the other and axially adjustable therealong by a screw 158 against a spring 156. In operation, a curved blade, with its concave portion facing downwardly towards the table 12, passes between rollers 24 and the leading end engages the plate 44, thereby earthing a sensing circuit through the frame to energize a solenoid 112 which effects dis-engagement of the clutch 34 and release of the rack 78 by the pneumatic cylinder 116, the application of the brake 40 to stop the rollers 24 and hence the blade travel and the engaging of the clutch 82 to allow the assembly 84 to drive the rack 78 and lower the continuously reciprocating hammer progressively into contact with the blade. As the hammer strikes the blade the cam 146 engages the follower 144 to provide an alternative energizing circuit after each blow is struck so that the blade will not be further advanced until the required straightening has been carried out at which point the blade end will remain clear of the plate 44 and the solenoid de-energized so that the hammer is raised and the rollers operated to advance the blade. The straightening sequence is carried out each time the blade contacts the plate. A straight blade will be fed by the rollers clear of and across the plate and out of the machine. Blades having double curvatures are repeatedly fed through the machine with their concave face downwards. A microswitch 160 is used to sense abnormal blade thicknesses &c. and to effect a shut down of the machine. A pair of hammers may be used. The electro-pneumatic circuit is shown in Fig. 7 (not shown).