Патент USA US2409843код для вставки
ÜCÍ. 22, 1946. 4 ' W1 A. EATON 1 2,409,842 FLUID PRESSURE CONTROL MECHANISM Arrow/¿Vs Oct. 22, 1946. 2,409,842 w. A. AEATQN FLUID PRESSURE CONTROL MECHANISM Filed July 5, 1944 3 Sheets-Sheet 2 l INVENTQJR. WiyîredÀEalbla. BY ,gé/¿Mn ? Oce. 22,` i946. W. A. EATON 2,409,842 FLUID PRESVSURE CONTROL MECHANISM Filed July 5, 1944 3 Sheets-Sheet 5 _ A Irak/vers Patented Oct. 22, 1946 2,409,842 UNITED `STlòlTlîS PATENT -LOFF ICE ' .2,409,842 _ v ` ' FLUID PRESSURE CONT-RGL jMECHANISM t‘Wilfred A. `~Eaton, gElyria, Ohio, assìgfnor Lto Bendix-Westinghouse Automotive t Brake Company, Elyria, 0hîo, a .corporation QfDEla Application suits, 1944, serial No. 543,564 >13 claims. (ci. , ’ 2 This invention .relates to, control `mechanism and 4more particularly >to fluid Vpressure Aoperated mechanism ¿for steering a vehicle. it has previouslyV been proposed tto provide power .operated mechanism for steering vehicles and `.more particularly fluid pressure operated mechanism wherein :the _energization of ia power actuator lis ¿controlled ¿by means of .a >lost `motion connection between the .steering Wheel oi v4the Avve hicle‘and the road `,Wheels of the vehicle, but ¿dif iiculty has been experienced on certain vehicles equipped -with this type of mechanism due to the fact that road shocks imparted to the road wheels .of “the vehicle have tended to take up the .slack in the )lost :motion connection with `-a resultant 15 energization of ,the :power ,actuator tending .to _cause continuous or vauto-reciprocation of .the ac, .tuator and of the road Wheels, more commonly `theretoy;,Shellielec;tly„te prerent yor ¿minimize auto-.reeiproeation er -. i erobieet ofthe :invention is te provide, in »c option with mechanism „of the above type, means controlled »by pressure `»conditiQns »in _a 1re eiproeating ilnidvmoter „ter control-lieg the :110W of pressure 'to r:the .control-valves of _the mo ter and .for thus @govemíxrsihe speed of .recip roeetionofçtheimoter. ,still durther ,object „Qi »the `,invention ¿is to epro ride, Connection with .a `double acting vfluid ïme tor tof the @above type, :means for, supplying suf .ñcient fluid zfpressureitepermît :rapid operation of the «device fender normal operating conditions, and for `limiting .the supply ‘Lof Vfluid pressureldur ine 'autofreçiproeationtorfmore rapid operation .to substantial-ly Prevent «such «reciproeation _from ,Continuing ' ’ known :as jshi-mmy, >and it is accordingly an object i ,These @11d V„other Edesi-roble ohjectsandvieatures of >the Vpresent ,invention to provide vmeans `for 20 of the invention will be @more lreadily `apparent overcoming .this undesirable condition. `when taken ¿in connection >-Wltli--the ,accompany ,It has :been .found ¿during experiments with .ing»drawingswhereinztwo embodimentsoi the in mechanisms of this type which ,employ a 4~double ventionris illustrated. .It :is »te .fbe expressly un» acting :iiuid :motor licor .turning the steering wheels der_stood, however, that the drawings are em in one `direction or "the other, that ¿during rapid 25 fnloyedwf rïpiiriloses .of ` ustratibn only, andere reciprocation ¿of the piston of the fluid motor, not designed las .a V_deñniti011 of »the limits -Of :the invention, referer-lee :being -hadror this _pur-.pose to the control vValves :for the motor ,are .unable .to thetappendedaelaims. ' l exhaust ñuid pressure ¿from the motor Awith suf ñcient ¿rapidity to prevent „the >pressure from in. i @In 4the :dra-wings, wherein :asimilar :reference creasing `at 'the `same time on `both Lsides .fof the 30 characters -~denote ¿similar lparts throughout ,the piston, <aridanother `object lof the :invention fis t0 utilize this -simultaneous increase .in »pressure on vboth sides >`of :the piston ¿for .the purpose _of :QP erating control Valve‘grmechanismito reduce ¿the supplyof :fluid Apressure _to the ,control .valves of the Arrlotor to a ¿point `Where the ñuìdpres Several views; Y Y «Fia l, of `the »valve :mechanism l for ‘ pair fof control valves :for alternately «supplying fluid :pressureitoonefend or `:the yother end of the .fluid motor, ,a 'pair- of Yconnections each normally operable tosupply huid-pressure from a lreservoir toíboth of ‘the .control valves, together with >means 45 controlled Joy the spressure in‘lone end -or” the `>mo tor :,for controlling 'the _flowvoof »íluid çpreS‘rSlll‘e through. one of `theseconnections and the _pres sure `in vthe :other fend >Vo_f the motor Á‘for controle ling ¿the `>:flow ._of :fluid pressure ¿through-the `other 50 „ n „hegsupplyfef ¿fluid pressure to "the " `fendjfigxt ,of «fthe :mechanism :taken vide, n in ¿a .mechanism ,of lthe ¿above type .having a ‘c ' ïFis.- .12 Vis te :partial »seccional view taken alone `îlet.another .object :of the „inventionfis >to xpro oftthesel-connections. ‘ lizin the presentfmventierl; `sx1-.re'suimlytis insufficient to sustain the „reeiprwv cation. , i rFîg. 1 :is :a :diagram-matie view. ¿partially in Sec ' of er :operated »steering apparatus uti n s. and f __ .. diagrammatic Mew-.partially »insee tíen, of ia .ower :steering mechanism »embodying anctheríiorrnfef the-invention. y V,Refmins»toeFis- .ofthe dreWinsSas-Well as t0 Fig. .ill-fthe steering meehenismiillustrated Vthere iniisfgerlerellygefwt txpeftdiselesedtintthe‘patent to #Stephen `Yereelrl` ¿en__d t „Stephen Johnson, ,.Ir., No. Zzllilöl?tL-,defterl Qetober :22, 119,35, thecontrol valve mechanism being substantially the samefas thatishown int-Eig. 2 `el’ theîpatent‘andïthe,lever age »mechanism i~f0r `operating»the .control valve »Still ¿another -object »of the yinvention is ,to ` pro vide, in a system of the above type having' `ation- mechanism, although .differing in detail, Qbeing adapteditoge?feet operation 4of l:the |control valve ble :acting fluid .motor :and -a ¿pair .Loffcontrpl ~ valves meohanismin ythe same Hrmanner as ythe leverage mechanism ,ShOWlllìn "thegpatent ‘.AS shown .in Eig.« f1` of the presentfapplication, ¿the v`power „op erated mechanism „includes la v.steering «wheel .4 Afor,;alternately¿supplying fluid »pressure-to „one end or :the ¿other _end of ìthe „fiiuid motor, mea-11S re sponsive to ipressure conditions inthetwo endSuOf the .zmotorgfor controlling thesupply -Qfflluid apres mounted ¿on «the puppen end fof-a `rotatable ¿shaft ~ 5, Surecfrom the msource to the >`:control valves ‘fior the shaft Aloeinc)providerl atlits lower end :with 1 a Worm@ adapted @te .engage a :Worm sector .1 hav the; urpose :of fiimitìns :the supply tot íluid ipresfY 2,409,842 3 ing a lever 8 on its lower end and rotatably mounted in any suitable manner on a` shaft Scar »ried by the framework of 4the vehicle, not shown. A tubular extension 39 serving to enclose the rod 36'is threadedly received Aby the piston and eX tends to the left through a seal 40' provided in 4the Wall 4I of the cylinder, the right end of the is such that on rota-tion of the steering wheel in' ~ >cylinder being closed by a cover plate 42. A con a counterclockwise direction; as viewed bythe one; 's ;trol valverrrnechanism 43 comprising a pair of identical control valves 44 and 45 is mounted on crater, the sector and lever will be operated in a clockwise direction about the shaft 9 to steer the «Y > the upper side of the fluid motor 33 as shown, the The arrangement of the worm and worm sectorv vehicle to the left, and will be'operated in the ¿op- `- f control valve ¿L44- being adapted to supply fluid posite direction when the >steering‘wheel is ro l0' pressure tothe right end of the motor through a passage 46, and the valve 45 being adapted to tated in a clockwise direction for the purpose of supply fluid pressure to the left end of the motor steering the vehicle to the right. ï f. " ' ` The dirigible wheels of the vehicle, -notsl'1_0ïvvn,. through ra passage 41. As shown in more detail in Fig. 2, the control Valve is generally of the type drag link lil having a pivotal connection II with 15 disclosed in the above referred to Vorech and are connected in the conventional manne-rte a vthe-lower endV of an'operating -lever I2, pivotally mounted for rotation on >alsh'aftl I3 carriedon Johnson patent. . Each of these :valves :isiad'apted the framework of the vehicle, and a mechanical arm 48 pivotally mounted on the valve mechanism by means of a pivot pin 49, rotationtof the rocker connection between the ïlever I2 and the l'ever 8 is eifected byl means of a connecting link I4 piv otally connected to the lever I2- by means 'of a pirr l5 and pivotally connected tov a valve operat to` be selectively operated byïmeans 'offa .rocker 20 armnin a clockwise direction being ‘adapted vto operate‘the valve 44:, 'and rotation' in the other - Idirection being adapted to voperate the valve 45, operation of the rocker arm by movement ofthe ing lever I6 by means of a pin I1, the lower end lever .I6 being accomplished by means >of a; lever of the valve operating leverbeing connected with thelever 8 by‘means of a connecting rod I8y having 25 50 formed on the Varm and connected withfthe valve operating rod 32 byvmeans of a universal a universal jointy connection I9 with the leverfIS joint 5I. Each ofthe vvalve mechanisms44. >and ‘and a universal joint connection 20 vwith the lever 8. ’ The lever 1:6> Vis supported on afpivot pin `2| '45 includes a normally open exhaust valve 52 ‘and normally closed inlet valve 53. `Each ofthe latter 'carried by a lever 22 mounted for free rotating movement onga shaft 23 rigidly mounted on the 30 valves is resiliently urged againstfa >seat 54 by frame, the 'arrangement-of >the lever and shaft being more fully illustrated in'lï‘ig.- 2. AAs shown in Fig. 2, the upper end of the lever I6 is provided with a hubiportion 24 having an 'l enlarged bore 25" in -'spaced relationship with the vsurface of a portion 26 ofthe shaft> 23,'and the llevers 22 and 'I6 are maintained on lthe shaft "23V between a shoulder 21 formed thereon and a washer 28 retained on" the end of the shaft by means of a suitable nut- 29; vrll‘hus the lever I61is so supported asto permit the enlargedbore 25 tonnormally as sume a concentric relationship with >theshaft portion 26, it thus being apparent that'on move meansfof a spring 55. The exhaustvvalves' are adapted to cooperatefwith seats 56 ïformed-‘on pistons 57 slidably received in cylinders 58 formed yin the ‘control valves, the pistons being ‘normally urged upward by means of springs 59. Valve ac- Y tuating stems Eil are slidably mountedin cover members 6l carried on the control valves andare directly connected or integrally formed with the pistons 51. Each of the valves 44 and 451s pro vided with an inletl and supply'conne'ction 62, the valve 44 being provided with van routlet cham ber 63 and the valve 45 being provided withan outlet 4 chamber 64. With.V the ' exhaust valves rnent'ofv the lever lßin' a clockwise direction about inthe position shown, these chambers are con-f the pivot pin I1, -the hub portion of theïlever- will nected with atmosphere through" passages 65 tend toumoveto the right until the- leftside of the enlarged bore engages the‘- left side of the sage 66 provided with an exhaustport 6l'. » Thus formed in the pistons and a common exhaust pas-l shaft portion 26. n As soon- as this engagement oc-`- onclockwise operation of the rockerarm to move I'one ofthe plungers 60 downward,.the exhaust 50 valve ofthe valveV 44 is closed andthe inlet valve 'connecting rod '318 ' byjy the steering »mechanism is opened to admit fluid pressure» to"-1the'fóutl‘et described, Will canse`> >the lever to pivot’ïabout the chamber 63, while on operation ofthe rocker arm line of engagement between the surface ofthe in the opposite direction, the plunger 6I) `of'the curs, further movement ofv the lever~v I6» in »fthe same direction fdueto' continued operation of the enlarged bore and the surfaceï‘of the shaft por valve 45 is moveddownward'to` closefthe exhaust tion 28, and the movementíof I'the leverïwill ac’ valve and open theinlet valve to admit fluidpres-w sure-"to the-outlet chamber` 64. As ’indicated in' vcordingly be imparted to the» lever I2 through the connecting rod I4,"`wit_h >-thelresu‘lt that'the’drag FigfZ and alsoshown in"Fig.î 1, the 'outlet cham link Ill will be moved tothe left to `steer the vehicle bers 63 and 64 are connected respectively~ with mechanically in that directiong'g--Thus the »lever the pass'agesvMìA and ‘il-leading to the right and I 6i is vpern'iitted Y -to' lrock "through" av -limited »arc 60 left ends of the cylinder,> the valvet44 thus serving in either direction'about the pivot Vpin ¿I 1, and this to control the pressure of fluid in'the right end movement is utilized to operate control mecha of the cylinden'while the valve 45 serves to con’ nism for a power actuator connected withï the trol the pressure in the ‘otherend of the cylinder. leve'r_I2.` _ -- y' The»V right and left inlet passages 62 of> thevalve The hub '24- of thelever I6,~` as shown inAFig. 2, 65 mechanism are connected‘by means ‘of a vconduit isprovided with aïportion 3U adapted to receive 68 which is adapted to receivefluid pressure‘from a ring Imember 3l rotatably mounted thereon,- and a supply reservoir l69 through means to be .herein-Y the ring member is provided with a valve'operat-V ing rod,32 for operating the valve mechanism; _ `In steering mechanisms of this't'ypaïthé .reserä after - As shown in Fig. 1, a double acting ñuid motorl33 is provided having a cylinder 34ïand a piston 35 slidably mounted therein,"a connecting rod 3ägpivotally’connected withthe piston by means described. » -Y ~ »f » « ' -4 ÍS voir is normally directly connected with the-inlet ports of the control valves, but in the presentin stance,v a control valve mechanism "I0 is inter' posed-betweenthe reservoir and thefconduit` 6'8 of> a pivot pin‘31 being connectedï’at its leftend leading to the valves 44 and 45, this valve mecha with the lever l2 by 'means -of -a Vpivot pin Á38. 75 nism being provided with an inlet port ‘H y connect 5 2,409,842 ed with the reservoir 69 through a conduit 12, and andfluid pressure is supplied to both of the cond~ an outlet port 13 connected with the conduit 68 by means of a conduit 14. A‘pair of iluid re ceiving-passages 15 and 16 are formed in the valve mechanism lilas shown and both connected to the inlet port 1I by means of a passage 11, trol Valves 44 and 45 from the reservoir through conduit 12, inlet port 1I, passage 10, passage 16, bore "i8, passage 19, outlet port 13', and conduits 14 and 68, it being apparent that in the event both of the valves 80 and 8| are simultaneously the‘ce'ntral portions of these passages being con closed, or partially closed, the supply of fluid nected by means of a bore 18 Which is connected with the outlet port 13 by means of a passage 19, pressure to the valves 44 and 45 will be substan 16 are connected by means of a common conduit valves on the cylinder, to supply the power neces-‘ tially reduced, with the result that insuiîicient it thus being apparent that both passages 15 and 10 iluid pressure may be supplied to the control sary to` sustain auto-reciprocation. 12‘ with the reservoir 69, and are both connected through passage 18, passage 19 and outlet port Assuming for example that the lever 8 is 13 with the valve supply conduit 68 through a moved in a counterclockwise direction to steer conduit 14. A valve 8l) slidably mounted in the 15 the vehicle tothe right, the lever I6 will be ro valve‘mechanism 1B is adapted on movement to the left to close the right end of the bore 18, a tated about the pivot I1 in a counterclockwise direction by virtue of its connection with the valve 8| similarly mounted .in the left end of the lever 8 through the connecting rod I8, and the mechanism 1€)Y being adapted on movement to the hub portion 24 will be moved to the left until right to close the left end of the bore 18. The 20 the right’wall of the enlarged bore 30 contacts mechanism 'lil is provided-at the right end with the surface of the shaft portion 26, thus serving chambers 82 and 83 separated by means of a flex to move thev valve operating rod 32‘ to the left ible diaphragm 84, the central portion of the to impart counterclockwise rotation to the rocker diaphragm being suitably clamped to the valve arm 48 as viewed in Fig. 2. When this occurs, member 80 as shown, with a spring 85 interposed 25 the plunger 60 of the valve 45 will be moved between a portion of the mechanism and the dia downward to close the intake valve and open phragm serving to normally maintain the Valve the exhaust valve, whereupon fluid pressure will in the open position shown. In like manner the be supplied from the reservoir to the left end of left end of the mechanism is provided with cham the cylinder through conduit 12 inlet port 1|, bers86 and 81 separated by means of a diaphragm 30 passage 11, passages 15 and 16, bore 18, passage 88` connected with valve 8 l, and a spring 89 serves 19, port 13, conduits 'i4> and B8, inlet port 62, open tomaintain the valve 8| in open position under inlet valve 53, outlet chamber 64, and passage A41, normal operating conditions. Thus with the parts` thus forcing the piston 45 to the right to impart in--the position shown, the inlet and outlet ports counterclockwise rotation to the lever I2 by vir 'il and 13 are connected through both of the pas 35 tue of its connection therewith through connect ing rod 36, thus moving the drag link I0 to the sages 15 and 16, and in the event one of the valves 88 and 8l is closed, the passage not closed by one right to turn the dirigíble wheels of the vehicle of the valves will serve to permit the continued to steer the vehicle to the right. As the pressure flow of fluid pressure- from the reservoir tothe increases in the left end of the cylinder, the pres control valves of- the fluid motor. 40 sure will likewise increase in the chamber 81- of ‘ As >heretofore stated, steering mechanism of the above type have a tendency toward auto-re ciprocation, the power necessary to maintain this reciprocation being supplied from the iiuid pres sure reservoir, and during such reciprocation, it 45 has been found that the valvesf44 and 45 are un able to exhaust `iiuid pressure from the cylinder 34 with sufficient rapidity to alternately reduce the valve mechanism 10, and when this pressure is sufficient to overcome the tension of the spring' 89, the valve 8| Will be moved to the right to close the left end of the bore 18 in order to pre vent further communication between passage 11 and the bore 18 through the passage 16. The passage 15will be still effective, however, to per mit the flow of iluid pressure to the conduit 14 thefpressure in one end or the other of the cylin and to theicontrol valves through the right end der to that of the surrounding atmosphere, and 50 of the bore 18, andthe mechanism is so adjusted that during normal operation of the steering » as reciprocation continues, there is a tendency for mechanism, one of the valves 80 and 8l will al-> ciable degree, due to the fact -that the valves ways be in open position in order to insure a have insuihcient capaci-ty to handle the large supply of fluid pressure to the control valves 44 volume of fluid being utilized in sustaining the 55 and 45 suflicient to elîect eiìicient and satisfactory operation of-i the steering mechanism. In the reciprocation. As indicated hereinabove, this event auto-reciprocation of the piston 35 oc action is utilized to control ‘mechanism `for con trolling the supply of ñuid pressure tothe con curs, however, the valves 44 and 45 will be rapidly trol valves-44 and 45, and to this end, the pas operated alternately by movement of the rocker sage 46 leading to the right end of the cylinderv 60 arm48? to rapidly supply iiuid pressure to the is» connected tothe chamber 33 of the valve cylinder and to exhaust fluid pressure therefrom, mechanism 'I8 through a conduit 98, whîle-the and `due to the rapidity of the reciprocation, passage 47 leading from the control valve 45 to neither end of the cylinder is completely eX the left` end of the cylinder is connected with hausted ofV ñuid pressure, with the result that the chamber 81v through a >conduit 98a, it being 65 the pressure gradually increases in both ends of noted iin this connection that the chambers 82 the cylinder to a value` sufficient to move the and B5 are at all times Vented to atmosphere diaphragms 84 and 88 against thetensionfof' the through ports` 9i'. Thus when iluid pressure is springs’ 85 and 89 to simultaneously close or par supplied to the right end ofthe cylinder, this tially close both of the valves 88 and 8|.` This pressure is likewise conducted to the chamber 70 action occurs almost instantaneously when the 83 and serves to move the diaphragm 84 to the left auto-reciprocationof the piston 35 is initiated, tol move the valve 89 to closed position, but in and as a result of the closing or partial. closing view of the fact that the left end of the cylinder ofthe valves in 'response to the simultaneous in-` is at atmospheric pressureduring this ltype of op-crease of pressure in both ends of the cylinder, eration, the valve 81 remains in open position, 75 the supply of fluid pressure-from the reservoir to ` this residual pressure to increase to an appre '2,409,842 8 both of the control valves through the passages 15 conduit‘14 is governed by the choke. Thesize and .16 and the bore i8 is either substantially reduced or entirely cut olf until such time as the pressures in the ends of the cylinder and in the ' of >fluid pressure to the control valves to a value chambers 83 and 81 drop sufliciently to permit »reciprocation ' In this connection, it is pointed ofthis choke isk so vchosen as t0 limit the supply slightly less than that required to sustain auto out that chokes have previously been utilized for by the operation of ythe springs 85 and 8D. Dur this purpose, but that in most cases thesechokes have been interposed in the passages 46'and 41 ing normal operation, however, operation of the adjacent the cylinder. The use of chokes in this valve44 to supply air to the right end of vthe cylinder causes pressure to be „supplied to the 10 manner has been of material advantage in mini mizing or eliminating auto-reciprocation, but at right end of the valve mechanism 10 to close the valves 80 and 8| to be moved to open position the valve 80, but on operation of the rocker arm to operate the valve 45, in‘response to reverse operation of the rocker arm when the steering the same time 'has so limited the supply of ñuid pressure to the cylinder as to prevent the latter fromv supplying the necessary amount of power wheel 4l is turned Vin the opposite direction by the vehicle operator, the speed of operation is to insure suñlciently rapid operation of the steer ing mechanism when the steering wheel is turned suchas to permit the valve 44 to exhaust the by the operator. Due to the location of the right end of the cylinder sufficiently to permit choke as shown between the main reservoir and opening of the valve 89 in the valve mechanism the auxiliary-reservoir, it will be readily appar 19 before the pressure of fluid in the left end of 20 ent that the relatively small `auxiliary reservoir >the cylinder and in the chamberfß'l is sufficient supplies suñîcient fluid pressure to permit the toclose thevalve 8|, the result being that dur cylinder to supply the necessary amount of pow ing this type of operation, one or the other of er t0 operate the steering mechanism when the the valves 80 or 8| isalways open and iluid pres steering wheel is turned Iby the operator of the sure is supplied at all times to the inlet ports of 25 vehicle, but that during auto-reciprocation, when both 'of the control valves44 and 45. When the a continuous supply of fluid pressure is required auto-reciprocation occurs, the operation is such by the control valves and cylinder and the oper that, as hereinabove described, both valves tend to close or partially close at the same time, and ation is much more rapid, the pressure in the res ervoir 94 is rapidly depleted to a point Where the the pressure at which such closing of both valves 30 flow of iluid pressure to the control valves is gov occurs can be `readily adjusted by properly pro ernedentirely by the choke 93, and it is thus pos portioning the areas of the diaphragms and the sible to choose a choke size and auxiliary res characteristics of the springs 85 and 89, these _ervoir size which will prevent auto-reciprocation being preferably adjusted in such amanner that and which at the same time will- supply sufficient simultaneous closing of both valves will occur 35 -ñuid pressure to maintain a normal working when vthe pressures on both sides of the piston pressure in the auxiliary reservoir during opera 35 exceed atmospheric pressure at the same time tionof the mechanism at normal speeds. s by a predetermined- value. Y 'There has thus `been provided in the present . Referring now to the embodiment of the in invention, as illustrated in the embodiments vention shown in Fig. 4, it will 4be seen that the 40 shown more particularly in Figs. 1 and 4, simple and eincient means for normally supplying suf mechanism for controlling the steering of the licient ñuid pressure from the main reservoir to vehicle is identical to that shown in Fig. 1, the the steering mechanism to insure satisfactory difference being in the means utilized for sup and unrestricted operation, together with means plying ñuid pressure from the reservoir 69 to the for automatically limiting the supply of fluid inlet ports of the control valves 44 and 45. In view of the explanation given in the preceding pressure to a value which is insuiiicient to sus-_ tain auto-reciprocation of the -mechanism when paragraph, it will be readily understood that dur such reciprocation occurs or tends to occur. ing normal operation of the steering mecha nismA by operation of the steering wheel 4, the While two embodiments of the invention have averagerate at which fluid pressure must be sup been illustratedand described with considerable detail, it will be readily understood by those v plied to the control valves to insure satisfactory operation of the ñuid motor is considerably less skilled in theV art that various changes, sub than that required to maintain auto-reciproca stitutions, and rearrangements of the compo nent parts may be resorted to without departing tion, and that through the inclusion of means in the fluid pressure supplyV system which4 is oper 55 from the spirit of theA invention. It is also to ative to re-duce or Alimit the supply of fluid pres be understood that the principles set forth may sure Vto the control valves during auto-“recipro be embodied in connection withV any suitable pow cation, this reciprocation may be minimized or er medium for effecting and controllingthe oper substantially eliminated. Tothis end, fluid pres ation of a fluid motor or power actuator. _Refer sure is supplied rfrom the reservoir 69 to the con 60 ence will, therefore, be yhad to the appended duit 14 leading to the control valves 44 and 454 claims for a definition of the limits of the inven through a «conduit 92 provided with a choke or restricted portion 93 and an auxiliary reservoir What is claimed is: i1. Mechanism for controlling the supply of 94, the capacity of the auxiliary reservoir being tion. ' ' ' suñîcient to insure satisfactory operation ofthe 65 fluid pressure from a source ,to a double acting steering gear cylinder during a normal >steering flui-d motor of the type having a pair of con operation to the left or right of the straight ahead trol valves and a control elementvfor operating said valves to alternately supply iluid pressure position, but being insuiñcient to sustain auto to one end or the other end of said motor, said reciprocation of the mechanism. In other words, as'soon as auto-reciprocation starts, the pressure 70 mechanism including a pair of connections eachv adapted to connect the source with both valves, in the auxiliary reservoir is »materially'reduced and means responsive to the pressure in one end due to the additional fluid pressure required to of the motor for closing one of said connectionsA sustain this auto-reciprocation, andthe rate of and responsive to the pressure in the other endl feed of fluid pressure to the control valves 44 and 45 through conduit 92, choke `§33, reservoir 94 and 75 of the motor for closing the other'of said con--` g,409,842 10 nections when said pressures reach predeter mined values. l connect the source with both control valves, means responsive'to thepressure in onefend of the motor l 2.v Mecha-nism,- for controlling the supply of for closing one of said connections when the pres sure „in said one end exceeds va predetermined value, andmeans `responsive to the pressure in fluid pressure from a source to a double acting fluid motor of `the type having a pairV of control valves and a control elementfor operating said valves to alternately supply fluid pressure to one end or the other end of said motor, said mecha other end exceeds ' a predetermined value. nism including a pair of connections >each adapt ed to connect the source with both valves, and sure, a double acting fluid motor, ,valvel mecha the `other end of the motorfor closing the other of said connections when «the . pressure in said 7. rllhe combination with a source of fluid pres means controlled by the pressure in the motor nism operable‘to alternately `supply fluidpressure for .controlling theflow of fluid pressure through to one end or to the other end of said motor, `and said connections including a valve forclosing one „of the »connections when the pressure Íin ‘one end meansforîconnecting_said sourceand valve mech ‘of `the motor reaches a .predetermined value and » a valve for closing the other connection when the pressure in the other end of `Athe motor reaches a predetermined Value. 3. Mechanism for controlling the supply of anism, of means associated with said connec tion means` controlled by the; pressure ‘in said motor for reducing the flow of fluid pressure‘be tween the source and valve mechanism when the pressures in both ends of said motor exceed a predetermined value at the same time including -a ñuid pressure from ‘a source to a double acting 20 valve controlled by the pressure in one end of the fluid motor of the type having a pair of control valves and a control element for operatingV said valves to alternately supply fluid pressure to one motor and another valve controlled by the pres sure in the other end of the motor. ' 8. The combination with a source of 'll-uid pres sure, a double acting-fluid motor, valve mecha end or the other end of said motor, said mech anism including a pair of connections each adapt 25 nism operable to alternately supply fluid pressure' ed to connect the source with both valves,`and to one end or to the other end of said moto-r, and valve means controlled by the pressure in Vone means for connecting .said source and valve mech end of the motor for controlling the flow 'of fluid anisrn, of vvalve means associated with said conpressure through one of said lc‘onnections and necting means for controlling the flow of fluid controlled by the pressure in the other end of pressure therethrough between said source and the motor for controlling the flow of fluid pres motor, said valve means including a pair of pas sure through the other of said connections. sages having a `common connection with the valve 4. Mechanism for controlling the supply of mechanism and a common connection with the fluid pressure from a source to a double acting source, a separate‘valvefor controlling the flow of ñuid motor of the type having a pair of control valves and a control element for operating said valves to alternately supply fluid pressure to one end or the other end of said motor, said mecha nism including a pair of connections each adapted to connect the source with both control valves, a separate valve for controlling the flow of fluid pressure through one of said connections, means responsive to the pressure in one end of the motor for closing said separate valve when the rpressure in said one end of the motor reaches a predeter mined value, a valve for controlling the llow of fluid pressure through the other of said connec tions, and means responsive to the pressure in the other end of the motor for closing the last named valve when the pressure in said other end of the motor reaches a predetermined value. 5. Mechanism for controlling the supply of fluid A35 fluid pressure in" each'of said‘p'a'ssages, means controlled by variations in the pressure of fluid in one end of the motor for opening and closing ` one of said separate Valves, and means controlled by variations in the pressure of liuid in the other 40 end of the motor for opening and closing the other of said separate valves. 9. The combination with a source of power, a reversible power actuator, control mechanism operable to alternately energize the actuator for 45 operation in one direction or the other, and means for supplying power from said source to said con trol mechanism, of control means associated with said supplying means for controlling the degree of power supplied to said control mechanism, said 50 control means including means forming a pair of power supply paths having a common connec tion with the source and a common connection pressure from a source to a double acting fluid with the control mechanism, a power controlling motor of the type having va pair of control valves element for controlling the degree of power sup and a control element for operating said valves 55 plied to the control mechanism along each of said to alternately supply fluid pressure to one end or paths, means responsive to the power supplied the other end of said motor, said mechanism in to the actuator to operate it in one direction for cluding a pair of connections each adapted to controlling the operation of one of said elements, connect the source with both control valves, a and means responsive to the power supplied to separate valve for controlling the flow of fluid 60 the actuator to operate it in the other direction for pressure through each of said connections, means controlling the operation of the other of said ele for normally maintaining said separate valves in ments. open position, means responsive to the pressure in 10. Mechanism for controlling the supply of` one end of the motor for moving one of said sepa power to a power operated device of the type rate valves to closed position, and means resp-on 65 having a reversible power actuator and control sive to the pressure in the other end of the motor means operable to alternately energize the actufor moving the other of said separate valves to ator Afor operation in one direction or the other, closed position. said mechanism including means providing a pair 6. Mechanism for controlling the supply of fluid of parallel power paths for supplying power to pressure from a source to a double acting fluid 70 the control means, means responsive to the power motor of the type having a pair of control valves supplied to the actuator to operate it in one di and a control element for operating said valves rection for controlling the degree of power sup to alternately supply fluid pressure to one end or plied to the control means along one: of said paths,A and means responsive to the power sup cluding a pair of connections each adapted to 75 plied to the actuator to operate it in the opposite ' the other end of said motor, said mechanism in 2,409,842 11 12 direction for controlling thedegree of power suD- y plied to the control means along the vother of regardless of the speed of Voperation of said valve mechanism including a connection between the source vand valve mechanism,` and'm'e'ans includ ing a. pair of valves controlled respectively by the said paths. ' 1l. Control valve mechanism for controlling the supply of fluid pressure to a double acting fluid pressure motor of the type having a pair of control valves and an element for operating said valves to alternately supply fluid pressure to one pressures of the >fluid -in opposite ends of the motor for controlling the flow of fluid pressure through’said connection. ' ì ' ` ' 13. Control --valve mechanism for controlling the supply of fluid pressure to a double acting end or to the other end of said motor, said valve mechanism including a casing having an inlet 10 fluid -motor of the type having a pair of control valves and means for operating one ofsaid valves port adapted to be connected toa source of fluid to supply fluid pressure to one end ofthe motor pressure', an- outlet port adapted to be connected and for operating the other of said valves to sup to each of said control valves, a pair of fluid pres ply fluid pressure `to the other end of the motor, sure passages both connected with the inlet port and with the outlet port, separate valves for cen 15 said control valve mechanism including a casing having an inlet port adapted to be connected to a trolling the flow of fluid pressure through each source of fluid pressure, an' outlet port lhaving a of said passages, means for normally maintaining connection With each of said control valves, a’ pair said valves in open position, a chamber adapted to of separate fluid passages each connected with be connected to one end of the motor, a chamber adapted to be connected to the other end of the 20 the inlet and outlet ports, separate valves for con- _ trolling thel flow of fluid pressure through each of motor, a member subjected to the pressure of fluid said passages, a pressure responsive member sub in the first named chamber for operating one of jected at `all times to the pressure of fluid in one said separate valves, and a member subjected to end of the motor for closing one of said separate the pressure offluid in the other of said cham bers for operating the other of vsaid separate 25 valves, a pressure responsive member subjected at all times to the pressure of fluid in the other end valves. of the motor for closing» the `other of said sep 12. The combination with a double acting fluid arate valves, and separatesprings for normally motor of the type having control valve mech maintaining each of said separate Valves in open anism adapted to supply ñuid pressure alternately to opposite ends of -the motor to effect reciproca 30 position until the pressure of the fluid to which eachV of -the corresponding pressure responsive tion thereof at different rates dependent on the members is subjected reaches a predetermined speed of operation of the valve mechanism and a source of fluid pressure for said valve mech anism, of means for limiting the speed of recip rocation Iof said motor to a predetermined value 35 value. ‘ WILFRED A. EATON.