US2440478A - Shuttle valve - Google Patents

Description

AWM 27, MAM. l n. A. mma

SHUTTLE VALVE f Film Nov. 24, 1942 Patented Apr. 27, 1948 PATENT oFFicE SHUTTLE VALVE Oumar A. Kehle, West Los Angeles, cam., as-

signor to Adel Precision Products Corp., a. corporation of California Application November24, 1942, Serial No. 466,784

This invention relates to hydraulic systems for operating aircraft controls and the like and more particularly pertains to a shuttle valve for adapting a system of this nature to immediate operation by means `of a motor driven hydraulic pump or a hand operated hydraulic pump.

' A primary object of my invention ls to provide an improved and highly efcient shuttle valve of the character described which when connected in a hydraulic'system including a hand pump and a rotor driven pump, will cut out of the system the hand pump and connect in the system the motor driven pump responsive to the operation of the latter and likewise cut out the motor driven pump and cut in the hand pump incident to operation of the hand pump upon cessation of operation of the motor driven pump whereby in case of failure of the motor driven pump the systemmay be instantly operated by means of the hand pump, the shuttle `valve being of simple construction, light as to weight, reliable in operation and instantly responsive to the operation of the two pumps to insure a reliable. operation of the system at all times. 1

Another object of my invention is to provide.

for a shuttle valveof the character described,

spring actuated detents which will not only possess the usual shuttle valve control features but, in addition, will function to oiset the eect of wear upon the valve and valve seats, -so that the valve will seat in a leakproof manner even after it has been in operation for a long time.

Another object of my invention is to provide a shuttle valve of the character described in whicha casing or housing, two inlets, an outlet means, a shuttle valve and a, spring loaded detent means are constructed and arranged so that.

under all operating conditions and at all times and especially when the shuttle valve is 4being shifted from either seated position to its other ,seated position only one of said inlets will be open 2 Claims. (Cl. 251-118) tional view of a shuttle valve embodying my invention; e

Fig. 2 is a sectional view taken on the line 2-2 of Fig. 1; A Fig. 3 is a part top plan-part sectional view of the valve;

Fig. 4 is a fragmentary view partly in end elevation and in part sectioned on the line 4 4 of Fig. 1; l

Fig. 5 is a front elevation of the valve;

Fig. 6 is a diagrammaticV view of'a hydraulic system showing the operation of the shuttle valve.

Referring to the drawing more specifically, 1 designates an elongated valve body member of a shuttle valve unit embodying my invention' and provided with a valve-receiving bore 8 extending longitudinally therethrough. Th'e ends of this bore are closed by screw threaded plug and valve seat members 8 the inner end portions of which constitute tubular valve seat members I0 and II.

Extending angularly (downward as-seen in Figs. 1 to 4 hereof) from and formed integral with end portions of the valve body member l are tubular connections I2 and I3 through which pressure i'luid intake ports Il and I5 extend into the end portions of the bore 8 so that pressure fluid may be delivered to either end of said bore.

The intake ports I4 and I5 open into counterbores IB inthe bore Bas shown in Figs. 1 and 4. These counterbores register with radial ports Il in the tubular valve seat members I0 and II and said radial ports are in communication with axial bores I8 afforded by said tubular seat members,

whereby pressure fluid may pass through said seat members into the bore 8 proper. l

Depending from and formed integral with' the valve body member at a point approximately 40 centrally of the end thereof is a box-like outlet connection I9 (Figs. 2 and 4) providing a pressure outlet port 20 which is communicated with the bore 8 by means of ports 2| and 22.

In the elongated valve chamber 4aiorlded bythe bore 'is a reciprocable shuttle valve generally designated 23 and provided with pistonlike valve members 24 and 25 at its ends and cam surfaces 28 and 2E between its ends. These valve members have a working tit in the bore 8 and are adapted to seat one at a time. In one position of the shuttle valve the valve member 24 thereon will seat against the seat member III while the valve member 25 is removed :from the seat member II, whereas in the other position of the shuttle valve. the valve member '25 is seated on the-seat member Il while valve member 24 is unseated.

When pressure uid is introduced for example through the intake port I4 andthe valve member 24 is seated on the -seat member I0, there being at this time no iiuid flow through the other intake port I5, the shuttle valve will be shifted to the right into position shown in Fig. 1 whereby the iluid will :dow past the thenrunseated valve member 24 and out through the port 2| and outlet port 20. Upon now shutting ofi. the ilow of pressure fluid through the port I4 and introducing pressure fluid through the port I5 the position of the shuttle valve is reversed and valve member 24 will seat while valve member 25 unseats, thereby allowing free flow of fluid from the port I5 past the open valve member 25, through bore 8, port 22 and outlet port 20.

Means is provided for effecting a snap action of the shuttle valve and for releasably holding said valve in its seated positions. i this means includes the cam surfaces 26 and 26 and a pair of spring loaded detents 21. These detents are mounted in tubular extensions 28 of the body member 8 and held therein by means of adjustable plugs 29, the adjustment of which As here shownwill vary the spring tension of said detents. These f detents engage opposite sides of the cam formation on the shuttle valve so that in one position of the shuttle valve the detents rest on the cam surface 26 and urge the valve member 25 towards its seat II while in the' other position of the shuttle valve the detents will engage the other and oppositely inclined 0am surface 26',

so as to urge the valve member 24 against the seat III. The detents have conical cam engaging ends 2l' and when the valve is shifted by the pressure fluid to an extent that the ends 21' of the detents ride over the narrow ridge 26 between said cam surfaces, the detents operate as cams to 'quickly eiect a snap movement of the shuttle valve to the limit of its travel in the direction in which it is being shifted by the uid pressure, thereby providing an instantaneous shifting and a fully responsive action of the valve unit to the shifting of the flow of pressure fluid. From Fig. 3 it is to be clearly seen that valve seat wear compensation is provided for by reason of the fact that the portions 21 of the spring pressed detents 21 can engageone cam face only, in such manner that the shuttle valve ,is urged against the seats, there being a clearance at such times at the opposite side of each detent to enable the detent fully to seat the valve even after the seats or the valves havevbecome considerably worn. In other words, the oppositely inclined cam fac's 25 and 26' which the detents engage,

are suiiiciently extensive and so positioned as to cause said detents to shift the valve an additional distance to compensate :for wear. One application of the shuttle valve unit here- `of to a hydraulic motor system is shown in Fig. 6

wherein a reservoir A is connected by a line B to a. motor driven hydraulic pump C which in turn is connected by a line D to the intake connection I3 and port I5 of my shuttle valve unit here generally designated E. A hand.- operated hydraulic pump F is supplied with fluid from the reservoir A -through a line G and is connected by means of a line H to the shuttle valve intake connection I2. A pressure fluid line J leads from in the position indicated in Fig. 6 with the valve member 25 unseated and valve member 24 seated so that the operating fluid will flow from the pump C, line D, connection I 3, port I5, past the open valve member 25 into the bore 8 and thencethrough port 22, outlet port 2li,l line J, control valve K and one of. the cylinder lines L and M to the hydraulic cylinder N, the iluld returningv through the valve K and line to the reservoir.

Should the motor fail to operate or in case it is shut off and operation ofthe hand pump F is necessary o r desirable, as soon as the operation of said hand pump is commenced, the pressure iluid therefrom iiowing through the line H enters port I4 and is at once effective againstl the valve member 24 to shift the shuttle valve to unseat valve member 24 and seat ,valve member 25, thereby connecting the hand pump in the system and shutting off the connection of the motor operated pump to the system.

It will be seen that the outlet 20 is of a bifurcated character its pair of branches 2| and 22 communicating with the midlength part of the shuttle valve chamber at axially spaced apart points, and that said shuttle valve, when open to any extent, even slightly, will prevent by-passing of fluid 'from one to the other end portion of the bore through said paired port branches. This action and prevention of interflow is brought about by the cylindrical portions of the shuttle valve being so spaced apart as to be simultaneously engageablewith the bore wall portions Vat opposite sides of the outlets 'iland 22 and disengageable with saidv bore wall portions one at a time to open the inlets and because said cylindrical portions remain in closing engagement with said bore wall portions on opposite sides of the outlets until the detent passes the apex of the ridge 26 for engaging one or the other of the two cam surfaces 25 and 26 in each direction of movement of the shuttle valve.

While I have shown and described a speciilc embodiment of my invention I do not limit myselfl to the exact details of construction set forth, and the invention embraces such changes, modiilcations'and equivalents of the parts and their formation and arrangement as come within the purview of the appended claims.

I claim: v

1. In a valve of the character described, a casing having a cylindrical bore therethrough and an inlet seat at each end of the bore and anout.

let means communicating with the bore intermediately of the seats, a shuttle valve slidable in the bore and having provision for alternately ento be simultaneously engageable with bore wall portions at opposite sides of said outlet means l and Mlead to opposite ends of a hydraulic motor and disengageable with said bore wall portions one at a time to vopen the inlets, said shuttle having a central ridge flanked by two centrally and outwardly inclined surfaces, and a spring pressed detent disposed intermediately of said seats and in position for engaging one or the .other of said the other of said seats. said cylindrical portions being positioned to remain in closing-engagement with said bore wall on opposite sidesoi said outlet means until said detent passes the apex o! said ridge in each direction oi movement oi the shuttle valve.

2. In a valve, a body member having a cylindrical bore therein. spaced inlet seats in said bore and outlet means communicating with' said bore intermediately of said seats, a shuttle valve slidable in said bore and having provision for alternately engaging said seats to open communication between a selected inlet seat and the outlet means. and close the other inlet means. said shuttle valve having cylindrical portions engaging the wall of said bore inwardly oi the respective inlet seats, said cylindrical portions being so spaced apart as to be simultaneously engageable with bore wall portions at opposite sides of.

said outlet means and disenzageable with said bore wall portions one at a timeto open said inlet seats.- said shuttle valve having two cam surta/ces, and a spring loaded detent disposed intermediately of said inlet seats for engaging one or the other oi said cam surfaces for urging g the' shuttle valve toward and yieldahly holding said valve against one or the other of said inlet seats. said cylindrical portions being positioned of said cam surfaces-in each direction of movel ,ment of said shuttle valve.

Number Name Date 1,768,625 Olsen July 1, 1930 il \1,778,757 Foi-ker Oct. 21, 1930 v1,908,889 Campbell May 26, 1981 '1,840,080 Snow Jan. 5, 1932 1,893,482 Wait Jam 31, 1933 i 1,955,180 Fargason Apr. 17, 1934 n 2,300,894 Overbeke Nov. 3, 1942 4F'OltlliIGN PATENTS l Number Country IDate 13,872 Great Britain Sept. 5, 1891 38,416 Denmark Aug. 13, 1926 211,710 Switzerland Jan. 2, 194i 333,385

`LKEHLE.

BEISBENCES CITED The following references are oi record in the ille of this patent: v

UNITED STATES PATENTS Great Britain Allg; 14, 1930

Images