Patent GB-517877-A (GB)
Title: Improvements in or relating to multiple valve units
IPC: F16K11/07
Filed: 1938-08-09
Abstract: 517,877. Multiple-way valves; relief valves. VICKERS, INC. Aug. 9, 1938, No. 23492. Convention date, Aug. 9, 1937. [Class 135] A multiple valve unit or bank for controlling both single and double-acting hydraulic motors comprises a number of interchangeable valve housings 11, 12, each having one or more motor ports 45, 47, 48 and each having transverse passageways, e.g., 23, 25, 35 which co-operate with one another, the ports and passageways of the housings of valves which control singleacting hydraulic motors being different in formation from those of valves which control doubleacting motors, but all the ports and passageways being so arranged that the housings may interchangeably co-operate with one another. The multiple valve unit shown in Fig. 1 has a relief valve housing 10, two control valve housings 11, 12 and an end plate 13. Pressure oil from a pump enters the port 14 and acts differentially in chambers 30, 31 at the ends of a relief valve 16 loaded by an adjustable spring 17. The valve housings 11, 12 respectively contain piston valves 19, 20 which are balanced as to the fluid pressures acting on them and are maintained in neutral position by springs 46, 50 with spring seats 46a, 50a respectively. In the neutral position, the port 14 communicates with an exhaust port 21 by way of ports 15, 22.... 29 formed in the three housings 10, 11, 12. The valve 19 controls a port 45 leading to single-acting motor, and the valve 20 controls ports 47, 48 leading to a double-acting motor. When the passage formed by the ports 15, 22 ... 29 is blocked or the pressure therein rises unduly, the relief valve 16 opens and oil passes through passages 32 ... 36 to the exhaust port 21. An alternative path for the fluid to exhaust is provided by passages 37, 38, 39, 40, 42, 43, the passages 39, 40 and 42, 43 being respectively connected by end caps 41, 44. The movement of the valves 19, 20 is limited by spacer sleeves 51. The motor port 48 is connected to exhaust when the valve 20 rises by way of a port 49 and a passage connecting this port with the passage 36. Both motors may be operated simultaneously if the valve 19 is raised slightly so as to open the motor port 45 whilst leaving the port 24 open. The modification shown in Fig. 4 has four control valve housings 57 ... 60, a relief valve housing 55 and an end plate 73 with an exhaust port 74 secured together by bolts 61. The relief valve is substantially the same as that shown in Fig. 1. Its inlet port 56 communicates with the exhaust port 74 via ports 75 ... 91, but should this passage become blocked alternative ways are provided by ports 92 ... 97 and by ports 98... 107. The first three control valves 62, 63, 64 are each centred by a single spring 66 arranged between spring seats 67. The first two valves 62, 63 are substantially the same as the valves 19, 20. in Fig. 1 and control motor ports 108 and 109 110 respectively. The third valve 64 is provided with two annular grooves 115, 116 connected to the central annular grooves of the valve spool by angularly disposed channels 113. 114, so that the exhaust from the motor ports 111, 112 is led to the pressure ports 88, 90 of the next valve via the annular grooves 115, 116 and the angularly disposed channels 113, 114. The last valve 65 has a " float " position in which both the motor ports 117, 118 are connected to exhaust. For this purpose, it has two annular grooves 120, 121 connected by radial channels with a central bore 119 connected to the exhaust passage 107 by channels 124. The valve has a centralising spring 69 with seats 71, 71a and within this a second spring 70 with a seat 72 having a flange which engages the lower spring seat 71 when the valve has been raised a certain distance which defines the " float " position. The valve 65 can also be moved upwardly or downwardly against the stronger spring 69 to expose the motor ports 117, 118 to the pressure ports 88, 90 respectively such movements being limited by a spacer sleeve 125. Lugs 126 for mounting the assembly are provided on the valve housing 55 and on the end plate 73. The valves may be operated simultaneously.