Patent GB-572701-A (GB)
Title: Improvements in or relating to fluid pressure remote control systems
IPC: F15B7/00
Filed: 1940-11-08
Abstract: 572,701. Fluid-pressure remote control systems. AUTOMOTIVE PRODUCTS CO., Ltd., and EVES, F. S. Nov. 8, 1940, No. 16262. [Class 69 (ii)] [Also in Group XXVIII] In a fluid-pressure remote-control system employing alternative operating or control devices, the actuation of the controlled member such as a bulkhead door is controlled by a series of interlocked valve members which enable the control from particular control members to take precedence of other members, and for one direction of operation, e.g. the closing of the door, one device has precedence of all others. As applied to a system in which a motor 11 which operates a bulkhead door can be controlled by a reversible hand-operated pump 17 arranged near the door, or by a similar pump 23 arranged on the bulkhead deck, or by a system including an accumulator charged by a power-driven pump 27 or an emergency hand-operated pump 46, the accumulator is connected by a non-return valve 33, line 34, to a valve 35 which is connected to the motor 11 by an interlock valve 16 to which also the pumps 17, 23 are connected. The valve 35 may be operated by a lever 36 or hydraulically under control of a selector valve 40 connected with the reservoir 22 which also supplies the pumps .17, 23. The interlock valve 16 is constructed as shown in Fig. 2, and comprises a pair of plungers 58, 60 in bores connected by a space 55, and a pair of connected plungers 66, 67 working in bores connected to the space 55 and to a space 56, all the plungers being pushed towards the right by springs. Additional pistons 59, 61 associated with the plungers 58, 60 are maintained by projections 62, 63 from close contact with their plungers or the ends of the bores, so that fluid can pass between the plungers and pistons, or between the pistons and ends of the bores. In Fig. 2, the valve members are shown in the position in which they assume when the pump 17 is operated to close the door. Pressure is produced in the pipe 19 and is directed by a passage 19a to the space between the plunger 60 and its piston 61 so that the plunger 60 moves to the left and also moves both plungers 66, 67 to the left and at the same time the fluid is caused to operate a piston 81 provided with a catch which holds the plunger 67 in position. The flow of fluid is via passages 19a, 85, groove 104, passage 83, 14a, pipe 14, and the return via pipe 15, passages 94, 84, groove 105, passages 86, 20a to pipe 20. The pistons 66, 67 cut off supplies from the pipes 37, 38 connected to the valve 35. When the pump 17 is moved to open the door, the plungers assume the same position as in Fig. 2 except that the piston 61 is also moved to the left by the action of fluid admitted via passage 20a, and the catch 80 is not operated. When the pump 23 is moved to open or close the door the action is similar, but the plunger 58 and piston 59 effect the controls. If neither pump 17 nor 23 are operated, all the plungers 66, 67, 58, 60 are moved to the right by springs and there is direct communication to the motor 11 from the pipes 37, 38 via bores in the valve block, and grooves 72, 73 ; 74, 75 in the plungers 66, 67. When the pump 17 is operated to close the door, a plunger 96 is operated to byepass the pump 23 to the reservoir 22 if it is operated in the door-opening direction, but if both pumps operate in the doorclosing direction they reinforce each other. The byepass is effected by moving the plunger 96 to the right and holding it in position by a spring-catch 100. Connection is thus made to a pipe 57 leading via pipe 39 to the reservoir 22. The operations described above in connection with Fig. 2 take place with the plunger 96 in its lefthand position.