US2483651A

US2483651A - Hydraulic valve

Info

Publication number: US2483651A
Application number: US624555A
Authority: US
Inventors: Arthur L Lee
Original assignee: Jeffrey Manufacturing Co
Current assignee: Jeffrey Manufacturing Co
Priority date: 1945-10-25
Filing date: 1945-10-25
Publication date: 1949-10-04
Anticipated expiration: 1966-10-04

Description

' Oct. 4, 1949. A. 1.. LEE 2,483,651

HYDRAULIC VALVE Filed Oct. 25, 1945 [NI/EN TOR; AETHUR L. LEE,

Patented Oct. 4, 1949' I name vsnvn Arthur L. Lee, Upp r Arlington, Ohio, assignor, by

means assignments, to The Jeffrey Manufactoting Company, a corporation of Ohio Application October 25, 1945. Serial No. 824,555

, 0 Claims. (01. 277-51) i This invention relates to a hydraulic valve, and an oblect'oi the .invention'is tovprovide an improved hydraulic valve. particularly of. the

solid or unbored spool type. which in one form of the invention includes a plurality of spools controlling separate double acting hydraulic mo- 2 central chamber 1 and also communicating with each bore 2 is a feed chamber 8. Each central chamber I of the'three right-hand bores, as viewed in the single flgure of the drawings, is in permanent communication with both of the succeeding feed chambers 8 .by means of a tors, the valve normally providing a substantial no-load by-pass when all the spools are in their neutral positions; the valve also having a pair of spaced drain passageways and one or more leakage passageways, one or both of which leakage passageways are always isolated from the hydraulic fluid pressure in the drain passageways for all positions of the spools.

A further object of the invention is to provide a single valve having the characteristics generally above defined.

Other objects 01 the invention will appear hereinafter, the novel features and combinations being set forth in the appended claims.

In the accompanying drawing, the single figure is a sectional view through the body or block of the valve, with the valve spools being shown in elevation.

This application is a continuation in part of my application Serial No. 530,361, flled April 10, 1944, for a Loading machine. Certain of the broad features of the valve are claimed in that application or a division thereof.

The embodiment of the invention which is illustrated includes a main block, body or castlng I which'is shown as a single integral body, though in certain aspects of the invention it may be built up of a plurality of adjacent separable body blocks. Within the block I there is a plurality of spools, all except one ofwhich are of similar construction and operate in substantially the same way. Because of this fact each of these similar spools and associated valve block 3 parts will be given similar reference characters.

The block I includes a plurality of similar parallel bores 2 which extend entirely therethrough and another bore 3 which is parallel to and spaced from the bores 2 but functions in a slightly difierent manner, as hereinafter described. At one end of the block I the bores 2 and 3 are closed by plugs 4. Within each bore 2 is a solid or undrilled type of spool 5. Bore 3 is provided with a spool 6 which is also solid or undrilled. While I have shown four similar spools 5, it is evident that the number may be increased or decreased as desired.

Substantially adjacent the center of each bore 2 and communicating therewith is a, central chamber 1. Located on opposite sides of each branching or bifurcated passageway 9, the pas sageway 9 obviously also functioning to connect the two feed chambers '8 in parallel. The feed chambers 8 of the right-hand bore 2 are also permanently connected together by a branching or bifurcated passageway it which is connected with and derives hydraulic fluid from a feed pipe or conduit II which constitutes the feed or delivery conduit from a pump or other source of hydraulic fluid.

Located outwardly of each of the feed chambers 8 is a motor chamber l2 or l3 adapted to be connected to a motor pipe or conduit. For example, each chamber l2 may be connected to one side of a double acting or reversible hydraulic motor, while each chamber 13 is connected to the other side thereof. It is, of course, obvious that the various feed chambers and passageways above described are formed within the main block or body I.

Outwardly of the motor chambers l2 and I3 and in communication with all of the bores 2 and the bore 3 the block L is provided with a pair of discharge or drain chambers or passageways l4 and I5 which cm'netogether adjacent the left-hand end of the block I and communicate with a discharge or drain pipe or conduit l6. Located outwardly of the drain passageways l4 and I5 and formed in the main block I in communication with bores 2 and 3 is a plurality of interconnected leakage chambers or passageways l1 and i8. Associated with the chambers or passageway l1 and in communica-' tion therewith is a plurality of oilseals i9 through which the spools 5 and 6 extend.

As hereinafter described more completely the chamber or passageway I! is entirely free of the pressure of the hydraulic fluid in the system, even including that in the drain passageway ii, and consequently there will be no tendency for the oil seals l9 to blow out or to leak. The leakage chambers or passageways I1 and it are both drained to an atmospheric pressure receptacle, thus eliminating any occurrence of pressure therein which is particularly important in connection with the seals l9.

This has solved a problem which was presented by the valve disclosed in my co-pending application above mentioned because in practice there is frequently a substantial amount of back pres sure in the discharge or drain passageways II and I5. In practice, this back pressure is often as high as fifty pounds and, in the absence of isolating the seals from such back pressure, they of which acts as a four-way valvefor controlling a reversible or double acting hydraulic motor. The function of the spool 3 and associated chambers and passageways is merely to provide for the selective reverse connection of a pair of parallel hydraulic motors associated with the last valve spool of the series of four and with the valve spool 6, as hereinafter described in complete detail.

As above mentioned, the construction of each of the spools 5 is the same. Each of said spools includes a central land 2| which, when the spool I 5 is in its normal or neutral position, occupies a position in the center of the central chamber 1, and the reduced shank portion of the spool 5 on opposite sides of the land 2I provides adequate clearance through the bore 2 to provide for normal free flow of hydraulic fluid delivered to the passageway I0 into the first central chamber 1 over parallel paths which feed the central chamber 1 from opposite sides.

When all of the spools 5 are intheir normal or neutral positions it is evident that a no-load by-pass series circuit is provided through all of the central chambers I and through the branching or bifurcated passageways 9 and the portions of bores 2 which interconnect the feed chambers 3 and the central chambers I; the hydraulic fluid in the last central chamber I being discharged to thedrain passageways I4 and I5 and the drain conduit I6 by way of the branching passageway 20.

It is to be noted that this no-load by-pass is provided with a solid or unbored type of spool and furthermore a parallel path leading from each feed chamber 8 to a central chamber 1 through a bore 2 and around the spool 5 provides a large cross-sectional area and thus a small resistance to the flow of the hydraulic fluid which produces a small pressure drop through the series of valves.

Each spool 5 is also provided with a pair of

spaced lands

22 and 23 which will seal the motor chambers s ools 5 are in their normal or neutral positions. thus locking or trapping the hydraulic fluid on opposite sides of the double acting or reversible motors. Near opposite ends the spools 5 also carry, isolating

lands

24 and 25 which isolate the chambers or passageways I1 and I8 from the discharge or drain chambers or passageways l4 and I5 for all positions of adjustment of the spools 5, thus entirely isolating the chambers or passageways I1 and I8 and thus isolating the seals I9 from the back pressure of the hydraulic fluid which may appear in the passageways I4 and I5.

The lands 25 are provided not primarily to protect any seals, but primarily to provide for a complete balance of the spools 5 which wo ld I2 and I3, respectively, when the not otherwise be present if the spools were cut on? before reaching the lands 25. However, in

certain broad aspects of the invention where a completely balanced spool is not necessary the lands 25 may be omitted and the spools 5- and 6 as well as the main block I may be foreshortened because of this.

s'lf a spool 5 is moved upwardly from its neutral position, as viewed in the drawing, the no-load by-pass will be shut off by the lands 2| and 23 filling the bore 2 on opposite sides of the central chamber 1. Simultaneously, the motor chamber I2 will be connected to feed passageway I0 and motor chamber I3 will be connected to drain passageway I5. This, of course, will produce actuation of the associated double acting motor in one direction. Reverse movement of the spool 5 from its neutral position will shut ofl the by-pass by the action of lands 2| and 22, while chamber I3 is connected to the feed passageway I0 and chamber I2 is connected to discharge passageway Il.

The action of each of the spools 5 is essentially the same. The spool 6 is of different construction as is its associated chambers and passageways and its relation to the adjacent spool 5 is substantially the same as disclosed and claimed in my parent application above identified or a division thereof.

Briefly described, it is as follows. The bore 3 has a central chamber 26 associated therewith formed in the block I. On opposite sides of the central chamber 26 is a pair of feed chambers 21 and 28 also in communication with the bore 3. Outwardly of the feed chambers 21 and 28 and communicating with the bore' 3, block I is provided with interconnecting

reversing chambers

29 and 30 interconnected by a passageway 3|. Block I is also provided with

passageways

32 and 33 which interconnect the motor chambers I2 and I3 of the last or left-handmost reversing valve 2, 5 with the feed chambers 21 and 28 of the reversing valve 3, 6.

The spool 6 has a relatively wide central land 34 and a pair of spaced

end lands

35, 36. The central chamber 26 is a motor chamber and the parallel connected

chambers

29 and 30 are also motor chambers, being common to a, single fitting or conduit. The spool 6 is only a two position spool rather than a three position spool as are the spools 5. Its function is to reverse the relative connection between the double acting motors associated with the valve 3, B and with. the lefthandmost valve 2, 5. For example, with the spool 6 in the position illustrated, the chamber I2 of the left-handmost valve 2, 5 is connected in parallel with motor chamber 29, while chamber I 3 of said left-handmost valve 2, 5 is connected in parallel with the chamber 26. This is one normal position of the spool 6. The other is achieved by moving the spool 6 downwardly as viewed in the drawme, under which circumstances motor chamber I2 of said valve 2, 5 is connected in parallel with the central chamber 26 and motor chamber I3 is connected in parallel with the motor chamber 29 by way of motor chamber 30 and passageway 3|.

From the above description, a number of characteristics of the valve are evident. First of all.

the valve is oi the sliding spool type, the sliding spool being solid or undrilled. when the valves are in their normal positions they provide a noload by-pass between the feed conduit H and the discharge conduit I8, thus substantially unloading any pump which may be continuously driven in the hydraulic system with which the valve is associated. The operation of any spool automatically shuts off this series circuit no-load by-pass and supplies hydraulic fluid under pressure to a motor chamber connecting the associated motor chamber to drain. A reverse operation of a spool Ii from its neutral position selectively connects an associated pair of motor chambers to drain and pressure. The spools are entirely balanced even as to any back pressure which may be present in the drain passageways it and II and it is particularly because of the occurrence of back pressure in such passageways that the isolating

lands

24 and 25 are provided, the former to protect oil seals Is, the latter when employed to provide substantially complete balance on the spools I.

While the block I is a unitary block to accommodate a plurality of valves, the complete assembly may, if desired, be built up of individual blocks, one for each spool 5. By the same token, in certain aspects of the invention it may relate to a single spool 5 and associated valve body, though in a more complete aspect of the invention it relates to a valve body either unitary or built up which accommodates a plurality of similar valve spools 5. This is particularly true in view of the series no-load by-pass which is provided, involving the branching or bifurcated passageways 9 which lead to the central chambers I from opposite sides through the bores 2.

Obviously those skilled in the art may make various changes in the details and arrangement of parts without departing from the spirit and scope of the invention as defined by the claims hereto appended, and I therefore wmh not to be restricted to the precise construction herein disclosed.

Having thus described and shown an embodiment of my invention, what I desire to secure by Letters Patent of the United States is:

l. A multiple spool hydraulic valve for controlling a plurality of hydraulic motors including a valve body, aplurality of spaced valve bores in said body, a solid type valve spool slidable in each valve bore, each valve bore having a central chamber communicating therewith, a pair of feed chambers communicating therewith and located on opposite sides of said central chamber and normally both communicating with said central chamber when the associated spool is in its neutral position, passageways connecting each central chamber with the pair of feed chambers of an adjacent bore, the above defined construction providing a continuous feed passageway through all of said bores and passageways with each central bore being'fed through a pair of passageways and feed chambers and through a valve bore from opposite sides of the central chamber, each of said valve bores also having a pair of motor chambers communicating therewith and located outwardly of said feed cham-v bers, a pair of parallel drain passageways located outwardly of said motor chambers and com- 'municating with said valve bores, a leakage passageway spaced outwardly of at least one of said drain passageways and communicating with said valve bores, seals for said valve bores communicating with said leakage passageway and through which said spools extend, lands on said spools which continuously isolate said leakage passageway trom the pressure of fluid in said drain passageways for all positions or adjustment or said spools, and lands on each spool operative on reverse movements thereof from its neutral position to connect one motor chamber to one or said drainpassag'eways and connect the other motor chamber to a feed chamber.

2. A. multiple spool hydraulic valve for controlling a plurality oi hydraulic motors including a valve body, a plurality of spaced valve bores in said body, a solid ype valve spool slidable in each valve bore, each valve bore having a central chamber communicating therewith, a pair of feed chambers communicating therewith and located on opposite sides of said central chamber and normally both communicating with said cen tral chamber when the associated spool is in its neutral position, passageways connecting each central chamber with the pair of ieed'chambers 01' an adjacent bore, the above defined construction providing a continuous feed passageway through all or said bores and passageways with each central bore being fed through a pair of eways and feed chambers and through a valve bore from opposite sides of the central chamber, each or said valve bores also having a pair of motor chambers communicating therewith and located outwardly of said feed chambers, 'a pair of parallel drain passageways located outwardly of said motor chambers and communieating with said valve bores, a pair of leakage passageways spaced outwardly of said drain passageways and communicating with said valve bores, seals for said valve bores communicating with one of said leakage passageways and through which said spools extend, lands on said spools which continuously isolate said leakage passageways from the pressure of fluid in said drain passageways for all positions of adjustment of said spools, and lands on each spool operative on reverse movements thereof from its neutral position to connect one motor chamber to one of said drain passageways and connect the other motor chamber of a feed chamber.

3. A hydraulic valve including a body having a valve bore therein, a solid type valve spool slidable in said bore, a central chamber communicating with said bore, a pair of feed chambers communicating with said bore and located on opposite sides oi said central chamber and normally both communicating therewith when said spool is in its neutral position, a, feed passageway connecting said pair of feed chambers in parallel, a pair of motor chambers communicating with said valve bore and located outwardly of said feed chambers, a pair of drain passageways located outwardly of said motor chambers and communicating with said valve bore, a pair oi. leakage passageways spaced outwardly of said drain passageways and communicating with said valve bore, a seal for said valve bore communicating withone or said leakage passageways and through which said spool extends, lands on said spool which continuously isolate said leakage passageways from the pressure of fluid in said drain passageways for all positions of adjustment of said spool, and lands on said spool operative on reverse movements of said spool from its neutral position to connect a motor chamber to one of said drain passageways and connect the other motor chamber to a feed chamber.

4. A hydraulic valve including a body havin a valve bore therein, a solid type valve spool acaaesi slidable in said bore, a central chamber communicating with said bore, a pair of feedcham- 8. drain chambers for all positions of adjustment of said spool, and means including lands on said bers communicating with said here and located age passageway spaced outwardly of at least one of said drain passageways and communicating with said valve bore, a seal for said valve bore communicating with said leakage passageway and through which said spool extends, a land on said spool which continuously isolates said leakage passageway from the pressure of fluid in said drain passageways for all positions of adjustment of said spooL'and lands on said spool operative on reverse movements of said spool from its neutral position to connect a motor chamber to one of said drain passageways and connect the other motor chamber to a feed chamber.

5. A hydraulic valve including a body having a valve bore therein, a solid type valve spool slidable in said bore, a pressure chamber, a pair of spaced motor chambers communicatin with said valve bore, a pair of drain chambers lcoated outwardly of said motor chambers and communicating with said valve bore, a pair of leakage passageways spaced outwardly of said drain chambers and communicating with said.

passageways from the pressure of fluid in said 40 spool operative on reverse movements of said spool from its neutral position to connect a motor chamber to one of said drain passageways and to connect-the other motor chamber to the pressure chamber.

6. A hydraulic valve including a body having a valve bore therein, a solid type valve spool slidable in said bore, a pressure chamber, a pair oi spaced motor chambers communicating with said valve bore, a pair of drain chambers located outwardly of said motor chambers and communicating with said valve bore, a leakage passageway spaced outwardly of at least one of said drain chambers and communicating with said valve bore, a seal for said valve bore communicating with said leakage passageway and through which said spool extends, lands on said spool which continuously isolate said leakage passageway from the pressure of fluid in said drain chambers for all positions'of adjustment of said spool, and means including lands on said spool operative on reverse movements or said spool from its. neutral position to connect a motor chamber to one or said drain passagew ys and to connect the other motor chamber to he pressure chamber.

. ARTHUR L. LEE.

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

UNITED STATES PATENTS Number Name Date 2,263,779 Jeffrey NOV. 25, 1941 2,276,357 Vickers Mar. 17, 1942 2,289,567 Berglund July 14, 1942