Patent GB-600079-A (GB)
Title: Improvements in or relating to control means for power presses and the like
IPC: F16D11/04
Filed: 1945-05-01
Abstract: 600,079. Operating clutches ; machinery guards. JONES (MACHINE TOOLS), Ltd., E. H., and HANCOX, F. A. May 1, 1945, No. 11035. [Classes 80 (ii) and 80 (iv)] [Also in Group V] Relates to a power press or other machine of the type wherein a reciprocatory member such as the ram of a press is arranged to be reciprocated by a driving shaft that is journalled in the machine frame and can be operatively connected with the driving means by a spring- controlled clutch which can be engaged and disengaged by a clutch-operating member, the machine being provided with clutch-control means constructed and arranged to effect non- repeat running or continuous running of the machine selectively at the will of the operator. According to the invention, the clutch-control means constitutes a unit or sub-assembly that is detachably mounted on the frame of the machine and is .arranged to control the movement of the' clutch-operating member. This member may also be arranged to stop the machine selectively at the will of the operator. The invention is shown applied to a press having a ram 18, Fig. 3, reciprocated by an eccentric 24 carried by a driving shaft 16 driven by a fly-wheel 26 through a dog-clutch 28. The clutch 28 is held in the engaged position by a spring 118, Fig. 6, which urges to the left a rod 30 which extends axially through the shaft 16 and is connected to the clutch 28. In order to stop the machine, the rod 30 must be pushed to the right against the action of the spring 118. The clutch control unit or sub-assembly is contained in a casing 32 detachably connected by pin-and-slot means 38 to the main frame 10. The unit compresses a cam block 100 arranged coaxially with and keyed on the shaft 16 to rotate therewith. In this block is slidably arranged a bar 96. When the bar 96 is held in its lower position, as shown in Figs. 4 and 6, the clutch 28 is held in its disengaged position by means of a lever 110 journalled in the block 100, this lever being forced in a counterclockwise direction by engagement of one end 112 thereof in a notch 102 in bar 96. In this position the other end 114 abuts against the rod 30 and pushes it to the right. When the bar 96 is allowed to rise, the spring 118 engages the clutch 28. The bar 96 is held down by the end 80 of a locking slide 68 which abuts one end of a lever 50 overlying the bar. The lever 50 is fast on a pivot pin 124 journalled in the casing 32, and a spring 58, acting on one end 54 of the lever, tends to raise the other end to allow the bar 96 to rise. A rocker frame 52 is fast on the pin 124 and carries rollers 128 which coact with cams 130 on the block 100. The slide 68 carries a rack 81 meshing with a pinion 90 loose on a shaft 88 which is rocked by means of an arm 86, Fig. 1, rod 84 and a treadle 82. A clutch 92, Fig. 5, which in one position connects pinion 90 with shaft 88, is carried on one arm 152 of a lever, the other arm 150 of which carries a roller 151 riding on the cam block 100. Operation. To start the press, the operator depresses treadle 82, thus turning pinion 90 and withdrawing slide 68 to the left, thus allowing spring 58 to raise lever 50, whereupon bar 96 rises and clutch 28 is engaged. After one cycle, cams 130 engage rollers 128 and rock lever 50 back to the position shown, slide 68 being returned by spring 72. If continuous running is desired, the rocker frame 52 is slid along pin 124, to a position in which rollers 128 will not be engaged by cams 130, by manual operation of handle 136. To put the press at safe, handle 136 is. rocked to a third position, in which a stop member 143 underlies the righthand end of lever 50 and so prevents ascent of the other end. A band brake 156 is applied by a cam 158 on block 100. When. treadle 82 is depressed, a safety guard is moved to protecting position. The guard comprises two frames 94, 95, Fig. 1, the frame 95 being connected to the shaft 88 by lever 89 and rod 93. The frames are shown in Fig. 11 in their' inoperative position. In their protecting position they are aligned with each other. They are aligned by rocking frame 95 counter-clockwise about pivot 97<1>, this rocking movement raising frame 94 by means of links 97, 99, 101, the frame 94 comprising a pin 194 which slides in guides 195 in the press frame.