US 2616259 A
Description (OCR text may contain errors)
L O R T N O C D N A S R O T O M E L P T. T mw M G N I D U L C N I M E T S Y S .C I L U A. R w. un
Nov. 4, 1952 B. F. QulNTlLlAN 7 4. 9 1 5 l V l u J d e 1 .1 F
mf .V m .b AM W c 8 "mw m 4 A a n a y I 2 w n, v, l.' Il! m/ L l b A 1o. 2 4 1.., /MH a ,ws l. L 1 /5 4 rwentor HIS Cttomcg BARTHOLOMEW l l 25/ 30e `through conduit I4to the motor I0.
wall of the casing around the vinlet opening for y closing off this opening from communication with both of the outlet ports. The fluid receiving chamber 22 preferably is suieiently large to dene a space with the piston for communication between the two outlet ports when the inlet port is closed as just described. In full retracted position, the piston head enters a reduced bore section 22a of the fluid receiving chamber 22. A cylindrical portion 23h of the enlarged end or head of the piston there servesV to close o'i the outlet port 25 While leaving inlet port open to outlet port 26. In intermediate positions of the enlarged piston end, between the opposite ends of chamber 22, the inlet port conveniently is open to both outlet ports. Y
The control valve preferably includes a pressure relief valve 30 as a unitary part thereof for relieving fluid pressure in excess of a certain amount. I usually build this relief valve into the control piston 23. Where this is done the piston illustratively has an orifice 30a in the tapered end portion 23a thereof, an enlarged axial b-ore 30h-for receiving iiuid` through the orice, and a ball check 3|lc normally seating over the orifice from within the bore. A coil spring 30d compressed in the bore 3'Ilbrbetween the ball and the innermost end of the bore serves vto maintain closure of the orifice up to a certain counteracting fluid pressure. 'I'he relief valve also has an outlet port 38e which empties into chamber 22 of the control valve and into outlet port Vas will be more fully explained hereinafter.
With particular reference again to the embodiment of my multiple motor hydraulic control system represented in vFigure 1, it will be seen that the aiding parallel branch circuit includes fluid pump I2, conduit I4 to junction 41, fluid line 48 leading from this junction to inlet'2I of the motor control valve 20, conduit I9 interconnecting outlet 26 of the control valve and inletside of the aiding motor II, fluid exhaust lines 42 and 44 extending from the motor outlet to the junction 2|, conduit I5 to the reservoir I6, and conduit I8 back to the pump. A lin-e 45 for bypassing fluid around both of the hydraulic motors I U and II leads from outlet 25 of the control valve to junction 43 with exhaust line 44. Y y
With the piston 23 of the control valve set to the position indi-cated in Figure 1 of the drawing, the inlet port 2| of the valve is closed. The hydraulic pump I2 during operation then draws fluid from the reservoir I6 and supplies this fluid A rotation thus is imparted to the rotor of this motor and the related shaft I3. Fluid exhausts from the motor through conduit l5 back to the reservoir. The iiuid pressure developed during this time on the inlet side of themotor is transmitted through line 48 to the closed inlet port 2I of the control valve. Should the pressure become excessive, such as by attaining a value beyond desired limits of operation of the system, the relief valve is opened, ball check 30e lifting and thus admitune Huid. through prima 30a, here, 3012.., Outlet 4 port 30e and chamber 22. A substantial quantity of this iiuid then escapes through outlet port 25. bypass line and exhaust line 44, to conduit I5 at junction 2I, and through conduit I5 back to the reservoir I6, thus circumventing the motor I0. This escape continues until certain operatinglpressures in the system are resumed, at which .time the relief valve 30 again closes'a'nd is held closed by the coil spring 30d acting on ball check 30o.
When the mot-or I Il alone is exposed to the energizing effect offluid supplied from the pump 'I2,' in the'manner described, shaft I3 serves -to Arotate the rotor of motor II.
y The idling motor II therefore tends to function as a, pump to the extent of its displacement. Thus, to avoid the development of a vacuum as on the valve 2n in View of thisl pumping action, I rely upon a iiuid the ball check 30o, this pressure recirculation circuit, including the motor II, the motor exhaust line 44, `line 45, outlet port 25 of the control valve, chamber 22, outlet port 26, and conduitle leading back to the motor. Fluid pumped by the motor, accordingly, passes at low pressure through this circuit without impairment or injury yto the system. At times, I nd advantage in employing an over-running clutch 50 between thejshaft I3 and the rotor of motor II for disconnecting the shaft and rotor when the motor I 0 alone is operating.
By displacing the piston 23 of the control valve to a position such as represented in Figure 2, thereby closing the outlet port 25 and putting the inlet port 2I and outlet port 26 in open communication, the aiding'motor II comes into operation, this while the motor IIJ continues operation. Where the pump I2 is a constant delivery pump, the same quantity 'of uid continues to come Vinto the system as compared with that in single motor operation. Fluid for producing the aiding motor function is pumped from the reservoir I 6 through conduit I8 by the pump I2 and then is supplied through conduit I4 to junction 41, thence through uid line 48, inlet port 2Iv of the control valve, fluid receiving chamber 22 of this valve, outlet port 26, through conduit I9 and the aiding motor 'I I,iiuid exhaustvline 42 vto junction 43, exhaust line 44 to vjunction 2'I, Yand thence through conduit I5 back to the reservoir. In the instance of high-torque low-speed operation of the motor II, the driven shaft I 3 receives the additional torque, Which'serves to supplement the output of the motor III. Should pressure in the system exceed the seating pressure of the coil spring 30d on is relieved by the relief valve 30. The relief is effected by fluid passing through orifice 30a,bore 30h and outlet port 30e, and to outlet port 25 in the control valve casing. vThe fluid then exhausts through lines 45,4 44 and I5, respectively, back to the reservoir I6, thus bypassing both motors. This bypassing action maintains until a suiiiciently low pressure is resumed in the system, at which time the. reliefvalve 30 closes. Both motors continue their coupled driving eifect on the shaft I3 until the piston 23 is reset to close the inlet port 2I as for resuming high-speed low-torque operation of the motor I0.
The high and low speed motor control positions of lthe piston 23 of the control valve 20 are conveniently achieved with theaid of suitable manual setting means, or by suitable automatic means for giving a setting of the piston consistent with the motor load. In positions of the piston between those giving single motor operation and multiple motor operation, uid admitted through inlet `cpeiling 2 I to chamber 22 and outlet opening 25, causes a sufllcient drop in pressure in the entire hydraulic system for stopping either or both motors.
Thus it will be seen that in this invention there are provided a multiple motor control system and control valve in which the various objects noted herein together with many thoroughly practical advantages are successfully achieved. It will be seen that the system is well suited for operating under load and for achieving single or multiple motor operation consistent with varying power demands. It will be observed also that the control valve is simple, compact and capable of giving highly satisfactory control over a plu- -rality of iiuid motors and enables the selective operation of one of these motors to the exclusion of another.
As many possible embodiments may be made of my invention and as many changes may be made in the embodiment hereinbefore set forth, it will be understood that all matter described and illustrated herein is to be interpreted as illustrative and not as a limitation.
l. A multiple motor control system, comprising in combination, a source of pressure fluid supply including a reservoir, at least two fluid motors connected in aiding mechanical relation with each other, a fluid circuit directly connecting one of said motors with said source of supply, a parallel fluid circuit connecting another of said motors with said source of supply, and a fluid control valve having a chamber with an inlet and two outlets connected in said parallel circuit, one outlet leading to said other motor and the other outlet leading to said reservoir, said valve having movable piston means in said chamber for selectively sealing 01T said inlet port ir 1 one position thereof and said other outlet port in another position and While in the inlet port closing position admitting intercommunication of said outlet ports, said piston means including an axial bore with spring seating valve means forming a pressure relief valve for spilling off fluid through the other one of said control valve outlets for said two iluid motors when the piston means is in either of the selected positions.
2. A fluid control valve comprising in combination, a casing having a fluid receiving chamber and an inlet port and a plurality of outlet ports for the chamber, and a uid control piston in said chamber for selectively sealing off said inlet port in one position thereof and one of said outlet ports in another position, and While in the inlet port closing position admitting intercommunication of said outlet ports, said piston including an axial bore with oriiice therein in continual communication with said inlet port, a ball check received in said axial bore, a spring also received in said bore and maintaining said ball to close said orice, and an outletl from said bore to effect pressure-responsive relief for said valve in either of the selected piston positions.
3. A fluid control valve comprising in combination, a casing having afiuid receiving chamber and an inlet port and a plurality of outlet ports therein for the chamber, and a uid control piston in said chamber for selectively sealing off said inlet port in one position thereof and one of said outlet ports in another position, and while in the inlet closing position forming a space with said casing wall communicating with said outlet ports, said fluid control piston including an axial bore with spring seating valve means therein for relieving fluid exceeding a predetermined pressure value in either of the selected positions of the piston and having an outlet emptying from said axial bore into the selective outlet port in the casing.
BARTHOLOMEW F. QUINIILIAN.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 12,966 :Stoddart May 29, 1855 382,643 Fox May 8, 1888 807,269 Hildebrand Dec. 12, 1905 965,052 Wainwright July 19, 1910 1,055,619 Dunn Mar. 11, 1913 1,156,816 Rich Oct. 12, 1915 1,349,924 Swanson Aug. 17, 1920 1,972,821 Weatherhead Sept. 4, 1934 2,023,524 Heaton Dec. 10, 1935 2,056,910 Schauer Oct. 6, 1936 2,337,499 Roth Dec. 21, 1943 2,370,526 Doran Feb. 27, 1945 2,374,588 Doran Apr. 24, 1945 FOREIGN PATENTS Number Country Date 64,014 Germany June 12, 1892 421,296 Germany Nov. 9, 1925 582,879 France Oct. 22, 1924