Patent GB-500324-A (GB)
Title: Improvements in or relating to duplex interlocked hydraulic broaching machine
IPC: B23Q5/06
Filed: 1938-04-12
Abstract: 500,324. Broaching - machines. LAPOINTE MACHINE TOOL CO., Ltd. (Lapointe Machine Tool Co.) April 12, 1938, No. 11228. [Class 83 (iii)] A duplex hydraulic broaching-machine has a pair of oppositely-moving broaching slides, associated with supports movable simultaneously and oppositely to loading and broaching positions, the work being secured by clamps which can operate only after the corresponding support has been moved to broaching position. The slides A, B, carrying carrying the tools are operated by alternately acting ram cylinders 10, 15, which are supplied from a reversible pump P, the direction of pump delivery being controlled by a lever 24 carrying an operating handle 26. The pump is neutralized automatically at the end of each working stroke by lugs 32, 38 on the slides engaging collars on rods 30, 36 connected to lever 24. The lever may also be operated by a power cylinder 42 controlled by a valve V which is normally biassed to a neutral position but may be moved in either direction by energizing one of two solenoid coils in the circuits 130, 131. The machine is also provided with a pair of work-supporting slides C, D, which are moved in opposite directions by a pair of hydraulic cylinders 52, 56 controlled by a valve V<1>. As shown in Fig. 4, the slide D is in a rearward position to locate a work-piece W in broaching position beneath a clamping member 80 while the slide C is in a forward loading position remote from the associated clamping means 70. The cylinders 52, 56 arc cross-connected as shown for simultaneous movement in opposite directions and the controlling valve V<1> is operated by a handle 65 which can only be moved when a locking plunger 66 is withdrawn by energizing a coil 67. The work clamps 70, 80 are respectively actuated by cylinders 72, 82 controlled by valves V<2>, V<3>, operated by handles 77, 87 and double-pole switches K, L are associated with the respective work supports, the switches being pressure operated so that only the upper circuit of each switch is closed when pressure is applied to the lower end of the corresponding cylinder to unclamp the work, and only the lower circuit is closed when pressure is applied to the upper end of the cylinder to clamp the work. The work slides may carry turntables 100, 110, Fig. 4, the table 100 haying index notches engaged by a plunger in a spring plate 105 having a portion 106 adapted to coact with and close an index switch M only when the work, properly indexed, is brought to broaching position. The table D has similar indexing means coacting with a switch N. The table slides have projections 92, 93 respectively which coact with and close switches G, H when the corresponding table is in loading, and the other in broaching, position. The slides A, B also have projections 90, 91 respectively which close switches E, F when one ram or other is in uppermost position. The interlock circuits are supplied from lines 120, 121. In operation, starting from the position shown in Fig. 1, the valve V<2> is moved to operate piston 71 to clamp work on slide C and to close lower circuit of switch K. A hand switch S is now closed and a circuit is completed through left-hand solenoid of valve V, switches H and M, switch K, and switch E. This shifts valve V and operates the pump control to move slide A downwards and slide B upwards. This opens switch E and valve V returns to neutral. At the end of working stroke of slide A, the collar 31 is engaged to return the pump to neutral. Lever 77 is now raised to'release the work clamp 70 and close the top circuit of switch K. Switch S can then be closed to complete a circuit through upper part of switches K and L and solenoid 67 so that control lever 65 may be moved to shift valve V<1> and cause forward movement of slide C to loading and rearward movement of slide D to broaching position. Handle 87 is then operated to lower clamping member 80. A circuit may now be completed through the right-hand solenoid of valve V through switches G, N, L, and F. This will move valve V to the right and the operative stroke of slide B will ensue until the pump is neutralized by the lug 38. The electric interlocks entirely prevent any incorrect operation of the machine.