US2545529A - Selector valve - Google Patents

Description

March 20, 1951 1 T, OBECNY 2,545,529

SELECTOR VALVE l Filed Aug. 21, 1944 3 Sheets-Sheet 1 J7" .Z1 2723.32 .27 ,23 2 7 .p 10

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J. T. OBECNY SELECTOR VALVE March 20, 1951 3 Sheets-Sheet 2 Filed Aug. 21, 1944 Fever-5 ed Weld/QZ Forward lD/Jsz-o/v Tosi-Zion Tosiz'on Filed Aug. 21, 1944 A 5 Shees-Sheecl 5 March zo, 1951 J,`T OBECNY 2,545,529

' SELECTOR VALVE RESERVOIR Afm/1 r//v Jin/Cf Patented Mar. 20, 1951 f` u g 2,545,529

5. UNITED STATES PATENT OFFICE Y 2,545,529 SELECTOR VALVE John T. obecny, Los Angeles, Calif. AppiicationAugust 21, 1944, serial No. 550,446

My invention relates to improvements in selector valves of that type which is adapted for use in any fiuid circuit at a point where` control of direction of ow and stoppage of flow is needed. Among the objects of my invention is the production of a valve which is 100% hydraulically balanced on both .pressure and return sides in either forward or return position in a high pressure fluid circuit, whereby the valve can be operated any time by a minimum of eiort either directly or by remote control. This type of valve finds ready use Awherever a double cylinder is used, or where reversal of rotation of any yiiuid actuating` device is desired. One such useis found in the hydraulic control system commonly employed in airplanes for controlling brakes, landing gear and other purposes.

To facilitate the opening of mainv control valves by hand it has been common practice to employ special auxiliary valves also under the pressure of uid medium which are controlled, but whichk can be operated without considerable effort to cause the full fluid pressure to act on the underside of the main control valve, thereby relieving the latter and enabling its easy operation.V If however, the full fluid pressure is not required for the actuated device connected to the main Vcontrol valve, then more than man power is required to open or close the main control valve, because of the excess pressure on the top of the main and auxiliary valves, and as a result the actuating device operates imperfectly. It has also been common practice to employ auxiliary valve means for automatically equalizing the back pressure of control valves, said means being applied in the pistons or piston of the main control valve, but such means has been found undependable and complicated. By the use of my improved valve these objections are overcome by a simple, hand or mechanically controlled and self contained unitary structure. Among further objects and advantages of my improved valve are maximum simplicity of construction, 'increased dependability and greater effectiveness in use.

In the accompanying drawings, forming part of-this specification, Fig.V` 1 is a central vertical section of my improved ...valve taken approximately on the line` I-I of Fig. 2, showing the parts in neutral position; Fig. 2 is abottorn plan of my improved valve; Fig. 3 is an end elevation of the structure shown in Fig. 1; Fig. 4 is a plan of the complete cam shaft unit when removed from the casing, which is employed for operating the sleeve poppet valves; Fig. 5 is a side elevation 0`f the cam shaft which is shown in Fig. 4; Figs.

' of a hollowcylindrical liner 23 abuts. This liner* 137 and 8 aresections of a detail taken on th line 6-5 of 1, showing neutral, forward and commodate the working parts of the valve and is shown having lugs I0 on its outer wall by which the structure can be secured and supported in a fluid circulating system for use. The casing is shown formed with a pair of parallel closely associated cylinders I I and I2 and with a transverse cylindrical bore I3 intersecting said cylinders, in which the valve operating cam shaft B is rotatably seated. rIwo transverse fluid circulating connecting ports enter the side of cylinder II, the port I4 being arranged. above one side and the port I5 below the opposite side of said cam shaft as lwill be'hereinafter set forth. The lower ends of cylinders II and I2 are provided with connectors I6 and I'I which are tightly secured by screw threading at I8 in the wall of the casing. These conneotors are adapted to beconnected with a prog pelling/ circuit of fluid such as represented by I9,

which may include any device to be actuated such i as-the cylinder and piston unit C shown in the diagrams appearing in Figs. 9 and 10. The above described structure provides two parallel cylindrical units D-Dk on one side above the camH shaft and two parallel longitudinally opposed cylindrical units EFE on the opposite side below i the cam shaft-' The members' of the upper two cylindrical units D-D are connected laterally through their sides by the transverse passage 20 in the wall of the casing, and the members of the lower two are connected laterally by the trans-v verse passage` 2l, also through the wall of the casing, the upper passage being coaxial and connected with the fluid pressure circulating port I4 and the lower passage being coaxial and connected with the fluid circulating port I5.

l Each cylindrical unit contains a poppet valve` structure which is composed of the following elements.

each cylindrical unit wall adjacent to the surface of the cam shaft B, against which the inner end is 'seated closely in the inner wall lof the cylinder First the casing is formed with a hori-. zontal shoulder 22 at the inner end portion of such as Il, and extends outwardly sufficiently to provide an inner annular valve seat 24 on its outer end and to accommodate a transverse passageway 25 which connects freely with one of the ports I4 or I5 and companion passages 20 or 2I. The cylindrical liner 23 is held inwardly in the companion cylindrical unit by the spacing collar 2S, stopper 21 and lock ring 28, the latter being engaged in the wall of the cylindrical unit and the stopper and spacing collar fitting tightly in said wall.

Reciprocably disposed and fitting closely in the cylindrical liner is the hollow cylindrical sleeve valve 29 whose axis intersects and is normal to the axis of the cam shaft. The outer end portion of this sleeve valve is formed with a cylindrical neck 30 and an inwardly tapering annular valve head 3| which normally closes upon the valve seat 24. The sleeve valve 29 is urged with its valve head closed upon said seat, in the neutral position of the valve by the helical expansion spring 32 which is interposed between the valve head and the stopper 21. The liner 23 has outer and inner packing rings 35 to provide tight surfaces between it and the inner wall of the cylinder andthe sliding peripheral surface of the sleeve valve. The space between the outer surface of the cylindrical neck 30 and the inner surface of the liner 23 forms a valve chamber 34 which is connected through the transverse connecting ducts 20 and 25 with ducts I4 and I5 and produces a connection with the compensating chamber 36 at the head end of the valve when the valve is thrust outwardly into open position by the cam shaft as will be hereinafter described.

All of the valve units are substantially similar in construction as described, except that the upper two F-F' and the lower two G-G' are reversed in position with their valve heads 3I tapering inwardly toward the cam shaft and instead of the stopper 21 and lock ring 28 being employed in each member of the lower two, the connectors IB and I1 are used partly for the same purpose.

The cam shaft B which is revolubly seated in the transverse bore I3 is provided with suitable hydraulic packing rings 31 for producing fluid tight connection with the casing and has two reversed pairs of oppositely extending, substantially at cam surfaces 38 and 39. One pair of these cam surfaces 38 is interposed between the inner ends of the pair of sleeve valves of valve units F and G, while the remaining reversed pair of corresponding cam surfaces 39, which extend laterally in an opposite direction from the rst pair is interposed between the inner ends of the pair of sleeve valves of valve units F' and G. A transverse annular channel 40 is provided in the cam shaft immediately below and communieating with a corresponding pair of sleeve valves and adjacent to and intersecting the cam surfaces, thus completing a longitudinal passage through each pair of sleeve ,valves of valve units F--G, and F-G, respectively including the valve chambers provided by the cylinders. The cam shaft has an integral stop shoulder 4I on one end and a stop nut 42 on its opposite end for retaining the cam shaft longitudinally in its seat which is provided by the bore I3 in the casing. The end of the cam shaft adjacent to the stop shoulder 4I also has a stem 43 and a laterally extending hand operable crank arm 44 by which the cam shaft can be rotated manually or by mechanical power when desired.

The shape and size of each cam for operating either pair of valves and the relative positions assumed for maintaining the valves in neutral, fully open or fully closed positions is illustrated respectively in Figs. 6-7 and 8, it being understood that pairs of cams for the respective pairs of valve units in the cylindrical units occupy positions extending outwardly in opposite directions about the circumference of the shaft and their substantially nat surfaces are only of suiiicient length to cause one valve to assume open position while the companion valve of the pair is released into closed position or when in neutral position all of the valves are released into closed position. In the latter position suicient clearance space as shown in Fig. 'I is provided between the cam surfaces and the ends of the valves 29 to permit the valve heads 3I to close tightly upon their seats 24. When uid pressure enters the valve structure via port I5, for illustration,

- and the cam shaft is rotated so as to lift and open valve 29 of the valve unit G, the diagonally opposite valve of valve unit F is simultaneously opened by the cam shaft and both of the diagonally opposite valves of valve units F and G' are closed, and vice versa, when the cam shaft is turned to close the valve of valve units G and F', the diagonally opposite valves of valve unit F and G are opened by the cam shaft. In this manner the fluid is controlled for causing the operation of the actuating device in either direction. It will be noted that the throw of the cam shaft from neutral position to forward or reversed posiion is through an arc of substantially 45 degrees either way.

Each pair of cam surfaces as stated is interii sected by' a transverse passage 4i] and the companion sections thus formed correspond in shape and size. Each section is formed with two parallel side faces. The cam faces which cooperate with the sleeve valve units F and G extend outwardly toward one side of the shaft while the cam surfaces which cooperate with the sleeve valve units F' and G are reversed, that is they extend laterally in opposite direction toward the opposite side of the shaft. The opposed positioning of these cam surfaces as stated at substantially degrees apartcauses the lpairs of puppet,V

sleeve valves to function simultaneously in diag-i onal relation as hereinbefore described.

The compensating chambers 35 which are provided at the head ends of each pair of valve units F and G and F' and G respectively, and which communicate via the longitudinal passage from end to end of each respective pair through the connecting channel 49 serve to equalize and balance the fluid pressure behind the laterally opposed sleeve valves both on the pressure and return sides of the fluid pressure circuit. The bore through the valve bodies are large in diameter completely throughout their lengths and consequently are capable of passing fluid with as little friction as possible without the assistance of auxiliary passageways in any member outside the puppet valves, whereby instant finger tip control accompanied by greater ease in operating and simplified construction is provided. Also chambers 45 in like manner through spaces around the cam shaft within the casing at the inner ends of the valves 29, of each respective pair of valve units further equalize and compensate any uneven pressure tendency so that the valves can be operated by minimum effort applied for rotating the c-am shaft.

My improved valve can be used in any hydraulic or fluid pressure circuit at a point where control of direction of ow and stoppage of flow is needed. The valve as shown in Fig. 1 is in neutral position, withilow owing. In Figs. 9 and 10, I have illustrated the operation graphically as applied to the cylinder and piston actuating unit C. The stippled space indicates the compressed fluid flow in the circuit when direction of flow is in either direction as applied to the actuating device. In order to induce flow from a pump and reservoir such assI-I and I respectively to and out of connectors I6 through duct I9 asshown in Fig. 9, for illustration, the cam shaft is rotated anti-clockwise from the position shown in Fig. 7 into the position shown in Fig. 6. This rotation lifts the valves 29 of valve units G and F off their seats, allowing pressure fluid to flow from port I5, where it is introduced from the reservoir I and pump H around the outside of the sleeve valve 29 of valve unit G, thence over to and around the outside of sleeve valve 29 past the seat 24, through compensating chamber 36, the coils of the return spring 32, down the connector I 6 entering the cylinder ahead of and urging the piston of the actuating unit C forwardly. The return ow of expended fluid reenters the valve simultaneously through connector Il and passes upwardly through compensating chambers l36 and the valve units G and F. After passing through the upper compensating chamber 36 and downwardly through the opening between valve 29 of the valve unit F and the companion valve seat 24 it traverses passages 2 o' and 25 and duct I4 and completes the circuit to the reservoir I. To reverse the stroke of the piston in the cylinder of the actuating element C as shown in the diagram, Fig. 10, the cam shaft is reversed and moved clockwise from neutral position shown in Fig. 7 into the position shown in Fig. 8, whereupon the valves of valve units F and G are opened and the valves of valve units G and F are simultaneously closed. In this position the flow of fluid is downward through Valve unit G into the cylinder behind and urging the piston of the actuating unit through its return stroke. The extended iluid in this instance returns via connector I6 and valve units G and F, thence through the opening between the valve unit F and its seat, and duct I4 b-ack to the reservoir I.

It will be understood that during the functioning of the valve as described the propelling uid enters the equalizing chambers 36 of the valve units G and F and the expended fluid enters the chambers 36 of valve units G-F, and in this manner any uneven pressure tendency exerted against the valves on opposite sides of the cam shaft is substantially instantly balanced. Also the chambers 45 which are also respectively connected in the same manner maintain iiuid pressure evenlyA around bearings of the cam shaft in the casing to minimize any uneven pressure tendency by the propelling uid.

The structure set forth above provides a selector valve which is particularly adapted for controlling the direction of flow in a hydraulic or other pressure uid circuit and which is automatically evenly balanced by the pressure fluid so that it can be easily and precisely operated either manually or automatically, directly or by remote control. It provides a unitary structure by which two separate circuits can be connected into the casing without outside ttings and permits of incorporating into the casing large valve chambers to be used particularly when extremely high pressure and high velocity are employed, to `eliminate cut off shock tendency. The valve also provides positive stoppage of ilow and self centering control. It further provides an assemblage of parts by which pressure loss developed through restriction'of ow of the controlled fluid pressure is minimized. The construction permits of modification by which the valve can be adapted for varying usages. For instance it is contemplated that the pairs of poppet valves can be radi-ally arranged degrees apart in a, circular casing with the'cam shaft at right angle to the plane of the poppets instead of at degrees apart as described above.

In accordance with the patent statutes, I have described the principles of operation of my invention together with the construction thereof which I now consider to represent the best embodiment thereof but I desire to have it understood that the construction shown is only illustrative and that the invention can be carried out by other means and applied to uses other than those above set forth without departing from the spirit of the invention and within the scope of the following claim.

I claim:

A selector valve, comprising a casing having a pair of laterally adjacent longitudinal valve chambers, a transverse shaft receiving bore intersecting and connected with said chambers between their ends, inlet and outlet ports in said casing, one of said ports being connected with both Vof said chambers on one side of said bore and the other port being connected with both of said chambers on the other side of said bore, an open ended poppet sleeve valve reciprocable in each outer end portion of both of said valve chambers, the sleeve passage being of large diameter throughout to freely pass fluid therethrough, a cam shaft rotatable through said cam shaft bore and having opposed cam surfaces for controlling the operation of said poppet sleeve Valves whereby turning the cam shaft in one direction causes operating iiuid and expended uid to traverse their respective Vsleeve valves 'and chambers in opposite directions and by reversing the cam shaft causes the said two uids to reverse their respective directions of ow through said sleeves and chambers, said valve chambers and sleeve valves providing free flow of fluid through said casing, and compensating means communieating with opposite ends of both of said chambers, whereby the pressure exerted by the operating fluid behind the poppet sleeve valves in one of said valve chambers is equalized and the presvsure exerted by the expended fluid behind the poppet valves in the companion valve chamber is also equalized.

JOHN T. OBECNY.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,165,001 Meyer July 4, 1939 2,349,069 Ashton May 16, 1944

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