US1797719A

US1797719A - Spring-reaction neutralizer

Info

Publication number: US1797719A
Application number: US233975A
Authority: US
Inventors: Grosvenor M Cross; Roderic M Cross
Original assignee: Individual
Current assignee: Individual
Priority date: 1927-11-17
Filing date: 1927-11-17
Publication date: 1931-03-24
Anticipated expiration: 1948-03-24

Description

March. 24, 1931. mb oss E 1.797.719

31 mm REACTION NEUTRALIZER' Filed Nov; 1'7, 1927 3 Sheets-Sheet 1 -l'nVen 23ers 6RosvENoRA L6R0ss fioDER/c M. CRoss ikq M4 (221M A TTORNE Y5 March 24, 1931. ca. M. CROSS ETAL 1,797,719

SPRING REACTION NEUTRALIZER Filed- Nov. 17. 1927 s Sheets-Sheet 2 4 Invenvqrs 6RosvENoR/M. cRoss Fromm/0M. CROSS A TTORNEYS March 24 1931. G. M. CROSS ET AL 1,797,719

SPRING REACTION NEUTRAL-IZER Filed Nov. 17, 1927 3 Sheets-Sheet 5 Inventors RosvzNor? M GRO65 RODER/c: M. Gnoss fi ul G m A TTORNE YS Patented Mar. 24, 1931 UNITE raves ATENT OFFICE GROSVENOR M. CROSS AND BODERIC M. CROSS, MINNEAPOLIS, MINNESOTA SPRING-REACTION NEUTRALIZER I This invention relates to an improved device or mechanism adapted for use generally to neutralize the reaction of springs or yieldable elements such, for example, as are used in the construction of automobiles, to cushion the loads carried thereby, the purpose of thus neutralizing the reaction of the springs being to prevent shocks and jolts from being transmitted to the body of the vehicle.

An object of this invention is to provide a device adapted to be connected between two elements separated or connected by a yielding means such, for example, as a spring, the device being so constructed that it will allow freedom of initial movement of the yielding means in. either direction from a normal or neutral position, that is, the construction of the device is such that it will offer substantially no resistance to the further separation, or the bringing closer together of the two movable elements, no matter from what cause the elements are moved; and while the elementsare returning towards their normal or neutral positions, the device will tend to oppose this return movement with a force which is at all points in the return movement, substantially equal to the difference between the normal pressure or tension of the yielding means and its pressure or tension due to its 30 deflection from normal, that is, the opposing I force may, be so adjusted as to be substantially equal at all times, to theamount by which its pressure or tension is greater or less than its normal pressure or tension, when the elements are in their normal relative positions.

A further object is to provide a hydraulic spring reaction neutralizer adapted to be connected between the frame members of a ve- "hicle chassis and the axles thereof, said neutralizer being so designed and constructed as to substantially counteract the reactive forces of the usual springs interposed between r the chassis frame and the vehicle axles, that is, when the springs are either compressed or expanded, as a result of the vehicle passing over a bump or a depression in the road-way, the neutralizer will act against the return of the springs to their normal positions, and -will neutralize such movement with the result that when the wheels encounter a bump or depressioninthe road-way, practically no jolts or shockswill be transmitted to the vehicle body.'

A further object is to provide a device for opposing the reactive forces stored in the Vehicle spring as result of its movement in either direction from a normal position, which comprises a mechanism adapted to be actuated by movement of the springs from a normal position, to cause an opposing force to be temporarily stored in the device, which acts to oppose the reactive forces temporarily stored in the vehicle spring; and the opposing force being greater at large and lesser at small deflections of the springs from normal, and the mechanism being so constructed that I the opposing forces temporarily storedtherein to counteract the reaction of the springs,

may be adjusted to obtain the desired degree of opposition to the reactive forces of the springswhen returning to normal positions, which will cause the travel of'the body to follow substantially a straight line; that is, the line of travel of the body will not be noticeably afiected by the wheels encountering bumps or depressions in the road surface.

A further objectof the invention is to provide a spring neutralizer comprisinga casing adapted'to be secured preferably to the side frame of the vehicle chassis, and having a rock shaft mounted therein to one end of'which a lever is connected, which lever has a connection with the vehicle axle, and a spring-actuated plunger being mounted within said casing for circulating the fluid therein, said plunger having a cam-shaped head adapted to be engaged by an arm secured to the rockshaft, the arm being so positioned upon therock shaft that-when the vehicle spring is in neutral position, the plunger will bejdepressed against a coiled compression spring which constantly tends to urge the plunger upwardly so that when the arm is oscillated in either direction from normal, by compression or expansion of the vehicle springs, the plunger will be moved in a direction towards the rock shaft, thereby causing the fluid to flow into the lower por- 1 tion of the casing through a valved opening;

(iii

and when the arm COD'IIHQIICGS return movement, as a result of the reaction of the vehicle spring, the plunger will be forced downwardly against the fluid confined in the lower portion of the casing, forcing the fluid beneath the plunger through a series ofsmall ducts normally closed by an annular valve seated under heavy spring tension, the tension of this spring being such that the mech by'a cam device,'whenithe=movable elements areimoved in either direction fromanornial.

position; to. provide such; a device comprising; aplunger andi-va-lve mechanism adapted to: controLcirculation of: a fluid therein,:said valve mechanism permitting substantially free circulation of the fluid: inone direction, but restrictingthe return flow of fluid in the opposite direction; toprovide an-tiefriction. meansifor' engaging-thecam' surfaces of the plunger to. minimize, friction; and; to, pro

vi-desuoh. a device of comparatively simple and inexpensive construction which will be substantially;fool=proof andpositive in performance and may be manufactured at a minimum cost. f

The particular object ofthe invention, therefore,. is to provide a spring reaction neutralizer, more particularly adapted-for use in connection: with vehicle springs for neutralizingthe reactive forces stored therein when in position other-than norma l Other objects of theinvention will appear from. the following description and accompanying. drawings and will be pointedout in the annexedclainis. s In the accompanyingdrawings; there has been, disclosed a structure designed to carry out the Various r objects of: the; invention,-. but

it istoabe understood that-,theinvention not confined to thereXact-featuresshown as various. changes may be made within the scope ofthe;claimsfiwhicli-follow V p In the accompanying. dra wings forming part ofthis specification Figure: I is a. sideelevational VIBW'Y'OI' a portion of a motor'veliicle showingthe iin-V proved neutralizen mounted thereon;

Figure -2isi a vertical sectional; View, p artial-liy in elevation, showing the'pa rtsain nor= mal or neutral-position;

Figure 3" is ahvertical sectionalwiew on 1 of a connecting rod 24, the lower end of which the line of Figure 5, showing infull and dotted. linest-hepositions assumed bythe rocker arm and plunger, when the vehicle spring is respectively compressed and expanded, the arrows in the lower portion of the figure indicating the flow of fluid upon movement of the plunger in a direction towards the rock shaft;

Figure t is a detailed'sectionalview of the lower portion ofFigure 3, the arrows indicating the flow of the fluid when the plunger is returning to normal against fluid pressure;

Figure 5 is an elevational-view'of-the device partially broken away to more clearly show the connection between the rocker arm and the plunger;

Figure 6 is a plan view of the adjusting nut provided for varying-the tension in the neutralizing spring; and

Figure 7 is a perspective view of the spring member provided for closing the annular check valve controlling fluid flow into the lower portion of the casing.

The-novel sprin reaction neutralizing device featured in" this invention includes a casing comprising upper and lower sections 2' andy3', respectively, the lower section 3 being secured to the upper section by means offaflanged nut 4, received in threaded engagement with'the uppersection 2 and having' an inwardly turned flange 5 engaged with anoutwardly turned flange 6, provided upon the upper edgegof the lower section 3. Anau-Xiliary fluid reservoir 7 may. be providedin the upper portion of; the casing as shown in Figure 5. This reservoir has a demountah'le cap 8 which may be removedto permit the introduction of fluid, such; as oil; 'ato the casing. In operation, thecasing is fli-led'w lrfluidl as indicated in Figure 3.

A-roclir-slraftfi is mounted in:bushings l1 and; 12, seated respectively in bores 13' and 141 as show-nin- Figure 5. A suitable packing- 16 is interposed between oneend of the'bushing 12 and-a nut: 'to prevent leakage of oil around the shaft .A lever-17. is mounted upon the rock: shaft 9; and is prevented from rotation thereon by means of splines 18. A lock screw 20 secures the lever 17 to the shaft. The inner end of the rock-shaft 9 is preferably smaller indiameter than that portion thereofw'vhichtraverses the packing nut 15. Axial movement of the rock shaft is prevente'das a result of the hub of the, level 17 engaging one end of thebushing 11, the other end of-which is seated against the bottonrofit'he bore 13 as shown-in Figure 5-. A spacingcollar' 21 has-one end seated against the OPPOE-iltfi side oftho lever 1'7 and i other end against shoulder 19, provided'in the, casing member 2.

An 22 is terminally secured tothe rock.

shaft 9, exteriorlyof the casing, and preferably.has a ball-and socketjoint 23 of ordinary constructlon, connecting it to'one end is. suitablyconnectedto the'ax-lc of the vehicle or to the non-flexing portion of the vehicle spring 25. Figure 1 illustrates a manner of securing the device to the vehicle and, as here shown, the upper portion 2 of the casing is secured to the front hanger 26 of the vehicle chassis by means of bolts 27 Thus, when the spring 25 flex-es, as a result of the wheel passing over irregularities in the road surface, the arm 22 will be oscillated to rock the shaft 9.

An important feature of this invention resides in the construction of the means provided for controlling the circulation of the fluid within the casing, each time the arm 22 is oscillated, as a result of the spring 25 being expanded or compressed. Such means consists of a plunger 28 reciprocally mounted in a cylinder 29, and preferably having an enlarged flanged head 31 received in threaded engagement with the lower portion of the casing member 3, as shown in Figures 2 and 3. The cylinder 29 is open at each end. The plunger 28 has a bore 32 adapted to receive a compression spring 33, the upper end of which is seated against the bottom of the bore 32 and its lower end against the bottom of the casing member 3. This spring constant-ly urges the plunger upwardly.

The plunger 28 has a forked head 34 provided with cam faces 35, one of which is constantly engaged with one end ofa stud 36 adapted to roll thereon. This stud is rotatably mounted in a suitable anti-friction bearing 37 mounted in the lever 17. The stud 38 has a reduced central portion 38, tightly fitted in the bore of the roller bearing 37. The opposite end of the stud 36 is reduced in diameter to receive a sleeve 39, secured to the stud by means of anut 41, terminally mounted upon the reduced portion of the stud, as shown in Figure 5. The inner race of the roller bearing 37 is clamped between the shoulder 10 provided on the stud 36 and the sleeve 39, thus securing the stud to the inner race of the roller bearing so that the enlarged end of the stud and also the sleeve 39 may roll upon the cam faces35, when the lever 17 is oscillated. The diameters of the enlarged end of the stud 36 and the sleeve 39 are identical. The swinging end ofthe lever 17 is received in the slot 42 provided in the head of the plunger, between the two cam faces 35. (See Figure '5.)

The valve mechanism employed in this novel neutralizer is best shown in Figures 2, 3, and 4. By reference to Figure 3, it Wlll be noted that the interior of the casing is divided substantially into two chambers, an

upper chamber 40, and a lower chamber '43. The lower chamber 43 is defined by the bottonrwall of the casing member 3, and the lower ends of the cylinder 29 and plunger 28. The upper chamber 40 is defined by the walls of the lower casing member 3, the exterior of the cylinder 29 and the upper portion of the plunger 28. In Figure 2, the leverlZ and plunger 28 are shown in normal positions, or in the I positions assumed when the vehicle spring 25 is in normal or neutral position. When the vehicle spring is compressed, the arm 22 will be moved upwardly to causethe lever 17v to assume substantially the position shown in full lines in Figures 3, wherein it will be noted that the compression spring 33 has caused by the plunger 28 to be moved upwardly, therer by causing fluid to circulate fromthe upper chamber 40 into the smaller chamber-43.

The valve mechanism provided for controlling the circulation of the fluid between the twochambers'consists of an annular ring 44, mounted in the lower portion of the member 3 of the casing beneath the head 31 of the cylinder 29; and a sleeve 45 movably mounted upon the exteriorof the cylinder as shown. A series of fluid ducts 54 are provided in the cylinder head 31 adapted to establish communication between the two chambers. These ducts are normally closed by the ring valve 44, yieldably held in closed position by means of a spring member 46, shown in Figure 7. A similar series of fluid ports 47 are also provided in the cylinder head 31, and these are preferably arranged in a circle closer to the bore of the cylinder and positioned tohave their upper'ends closed by means of the lower end of the sleeve valve 45, as shown in Figure 3. The upper discharge ends of the ports 47 communicate with an annular groove 50, provided in the cylin} der head 31. This annular groove is adapted to be closed by the lower end ofthe valve sleeve 45 as shown. An annular flange 48 is provided on the sleeve 45 against which one end of a compartively heavy compression spring 49 is seated. The other end of this spring is seated against an adjusting nutbl,

received in threaded engagement with the upper end of the cylinder 29 and having'a key 52 engaged therewith and with the bore provided in the lower portion of the upper casing member 2, as shown in Figure 2. The key 52 prevents the'adjusting nut 51 from relatively rotating with respect to the casing member 2. To adjust the tension of the spring 49, the flanged nut 4 is loosened, after which the lower casing member 3 may be relatively rotated with respect to the upper casing member 2, thereby causing the cylinder to be relatively rotated within the nut 51, with the result that the distance between the flange 48 and the lower face of the packing nut 51 is varied, thus changing the tension of the spring 49. A' drain plug 53 is preferably provided in the bottom of the casing member 2. Two tension springs 49 are preferably employed. These are concentric and of the same diameter and are arranged with their coils alternating. of the two springs are preferably bent up- Thev upper terminals 55' wardlv': and seatedin 1 apertures 56; provided in'the nut 51.; The nut 5l also has-itsperipherynotchedas shown in. Figure 6 to provide fllllClTCl'lC'tll ating passages.

Operation Inoperation, the entire device'is filled witha fluid such as oil, the auxiliary oilj chamber 7 being supplied with fluid as desired, to take care of expansion or contraction of: the fluid, due to temperaturechanges. A vent 57 is provided inithe capS defining-the upper wall of the. chamber 7.

Then the vehicle wheel engages an irregularity. or a bump inthe road-way, causing the vehicle spring to compress, the arm 22' will: :beoscillated from-the full line position shown/in Figure 2 to the full line position shown inpFigure 3, thereby rocking the shaft 9. andcausing ,thelever 17 to be movedfrom the position showniin Figure 2to the full; line position shown, in Figure 3. Such movement ofthelever 17. permits the compression spring 33 to move the plunger. upwardly, the cam faces 35ikeeping incontact' with the head ofthestud 3.6 and the sleeve 3.9;. As-the plunger 24. rises, a slight vacuum occurs .in the chamber 43, and atmospheric pressure forces the; fluid in the upper chamber throughzthe ducts;

; 5d and into. thechamber, the Valve ring: 44

being unseated, asshown inFi ure 3, by the pressure of the. fluid actingthereagalnst. Thus, the lower. chamber-.43. willbe kept: full of fluid re ardl'ess of-the movement of the plunger. 28. It isobvious thatthe action. above. described, offers noimpedance to the movement ofthe vehicle. axle under thebody so longas it continues towards-the body; that. is, asfthe two.movable-elements.in thisinstance, the vehicle axle andthe-ch-assis frame members, are movedtowardsieaohiotherfrom: their normal: positions, .the device. ofi'ers :no impedance. tothat movement. As the wheel drops beneath the body. or into: a depression in the road surface, the action is similar, the lever 17', however, swinging to thedotted. line position shown in Figure 3, Themovement of the arm 22- w-ill also bein theopposite direction, as indicated by the dotted lines in Figure 3. hen the par-ts are thus positioned,

' it will be noted that the stud 36 and sleeve 39 will be in contact with the cam faces 35 at points theother side of the vertical. Thus, it will be seen that the free travel of the.

" plunger 28.will be in the samedirection or upwardly, regardless ofv whether the lever 17 is moved from normal to the full or the dotted line positions shown in Figure .3. It, will benoted that the device will permit the movable elements such, for example, as the vehicle chassis and'v'theaxle, across which it isconnected, to be moved in; eithendirection away from, normal position,,4that, is, itpe-rmits a free initial deflection of the yielding-connection from its original degree of deflection.

When the parts have reached the positions indicated inwfnll-lines in FigureS, the exe cessive pressure or reactive force present in the vehicle spring resulting-from its compressed conditiom tends toreturn the vehicle.

axle to. its normal position, thereby exerting a, force against the outer end of the arm 22 tending to move it downwardly from the full line position shown in Figure 3 to the full line position shown in Figure 2. In order to move in this direction, it is obvious that the plunger 28 must be forced downwardly as a result of the stud 36- and sleeve 39 acting against the camfaces 35, as the lever 17 returns to its normal position, shown in Figure 2. Such downwardmovement of the plunger- 28will causethe latter: to force the fluid into the chamber--10, causing the sleeve valve 45 toibe opened against the pressure of the spring -19, thus permitting fluid to flow from the lower into the upper chamber, as indicated bythe arrows in Figure 4. The force-necessary to. force the. plunger 29 downwardly, is exertedbythe-stud 36. andnsleeve 39 against thecam; faces 35; and hence must beexerted between body and axle. It is obvious, there-- fore, that this force opposes the return move ment ofthebody and axle to their normal relative-positions.

The action of the plunger and valve mech-. anism,whe-n. the armi22 is moved from the dotted line position shown in Figure 3 to the full line position shown in Figure 2, is practical-l-y identical, to. its action or operation, when the arm 22 moves from. theful-l line positionshown in Figure. 3 to its normal posi tion. This. will readily be seen when it is understood that the return movement of the arm 22from either of the positions shownin Figure 3,.to'i-ts normal position shown in. F ig.. ure 2, cannot be effected without forcingthe plunger downwardly, which movement is 01)? posed'by the action of the spring 49 tending to retain the sleeve valve 45 in closed position. A back pressure is exerted against the return movement of the arm 22 in either direction, through the cam faces 35, stud .36 and slee-ve39; lever 22, lever 17, shaft 9, and the connection: 24 between body and axle; thereby opposing their return movement to normal relative positions. Hence, the device will, when connected between two relatively movable members connected by a yielding connection, allow free initial movement of said members. in either direction from a normal position, either closer together or fartherapart; and, conversely, it will also oppose the returnmovements of said movable members towards their normal positions from either direction.

The magnitude of the force opposing the. return movement of the movable elements, such as vehicle body and axle, at any given .plungerwith such force that point, is determined by the following factors; the lengths of the arm22 and the connection 24, and the angles at which they are operated from their connection with the vehicle axle; the diameters of the head of the stud 36 and the sleeve 39; the shapes of the cam faces the effective areas of the plunger and the valve sleeve 45, and the pressureof the spring 49.- For the purpose of explanation, it will be assumed that all of these are constant with the exception of the cam faces 35 and the size of the spring 4-9.

The shapes of the cam tially determine the ratio of successive increments of the opposing force to successive increments of deflection of the vehicle spring, whereas, the pressure of the spring 49 will determine the exact amount of the opposing pressure; that is, the ratio of the amount of vertical travel of the plunger during an elementary unit of travel of the axle beneath the body, to the amount of that axle travel, determines the mechanical advantage or lever age of the plunger vover the axle during that amount of travel. In other words, the cam faces 35 act as a variable leverage factorbetween the plunger 28 and the vehicle axle. Thus, almost any relationship of leverages from point to point can be obtained bysimply varying the shapes of thecam faces $5. The pressure of the spring 49 together with the effective areas of the sleeve valve and the plunger 28 determine the upward force of the plunger; and this force multiplied by whatever leverage the piston has over the axle at any given point of travel, determines the exact value of the opposing force exerted by the neutralizer between body and axle.

Thus, by properly designingor shap ng the cam faces 35, and properly proport oning the lever 17 and arm 22, with a constant velocity of initial axle rise beneath the body, the plunger can be made to travel Witllllnlformly accelerated motion that 1s from zero velocity at its lowest point to maximum at its highest, thereby givin an even change of leverage between the plunger and theaxle, the leverage'being at all times proportional to -the degree of deflection of the veh cle spring, and therefore to the amount by which the pressure of the spring 15 greater or less than normal. Hence, if the upward force on the plunger is sufficient exactly to oppose the amount by which the vehicle spring 1s greater or less than normal at any one point, it will be so at all other points, as the leverage of the plunger on the axle changes wlth the force desired. V

As a result of the adjusting nut 51 being mounted for relative vertical movement within the casing, the tension of the sprlng 4.9 may be varied to give the desired pressure, that is, its tension may be adjusted so thatit will oppose the returnmovement of the faces substanthe apparatus,

as a whole, will oppose the return movement of t-he vehicle spring with a force at all points substantially equal to the difference between the normal pressure of the vehicle spring and its pressure at these points due to sure'is not directly proportional to the de gree of its deflection, the cam faces 85' may be changed or altered to fit the new conditions and to give always the proper leveragesif it is desired to oppose with pressures not equal to but proportional to the amount by which the pressure of the yielding means is greater or less than normal, th-ecam faces will remain unchanged, it being only necessary to change the pressure factors acting on the plunger, namely, the tension of the springs 49, together with the fluid areas involved. To obtain other desired forces, the shapes of the camfaces 35 will be altered to fit the particular case. It is obvious that any downward curve of these cam faces, or even a horizontal flat surface, will produce forces at the axle greater at large deflections of the spring and lesser at small. The other forces attainable by varying the shapes of thee-am faces 35, are only limited by the curvature of the head of the stud 36 and the sleeve 39, which will not allow too great a sudden change of angle, and the various other simple mechanical factors involved.

From the foregoing, therefore, it will be. seen that the construction of this novel spring reaction neutralizer is such that it may be readily adapted for nsein connection with two movable elements having a yielding coniection between them, to substantially oppose the reactive forces stored up in such yielding connection after deflection and when tending to return to normal position, or it may be made to give opposing forces not neutralizing but of almost any value desired.

Vi e claim as our invention:

1. A device for opposing the reactive force in a spring element connecting together two relatively movable members, comprising casing adapted to be securedto one of said members, a rock shaft in said casing having an operative connection with the other of said members, fluid chambers in said casing, an inelastic fluid therein, a valve mechanism be tween said chambers, a plunger for circulating the fluid between the chambers, head on said plunger having an off-set portion, and means on the rock shaft adapted'to engage said off-set portion and depress the plunger when said shaft is rocked.

2. A device for opposing the reactive force ina spring element connectingtogether two relatively movable members, comprising a casing adapted to besecured to one of said members, a rock shaftdn said casing having all Q whensaid sh ait is an operative coi'ine'etionwiththe other of-said 1nembe'rs,f fluid chambers in said easing-an inelastic fluid therein, a valve mechanism between said chambers, a plunger for circulating the fluid between the chambers, ahead tially at right angles to the axis oi-said plunger and being adapted to engage the offset portion on-the plunger head, said oliset portion causing the plunger to be depressed farther when said plunger-actuating means is at one end of its movement'than when said means is at the opposite end of its movement.

3. A'dev-ice for opposing the reactive force ina SPIlTl'g'OlelllGllt connecting together two relatively movable members, comprising a casing adapted to be secured to'oneot said members, a rock shaft in said casing having an operative connection with the other of said members, fluid chambers in said casing, an inelastic'fluid therein, a valve mechanism betweensaid cha-mbers,'a plunger for-circulating the flu-id" between the chambers, a head 011 said'pl'unger having an oil -set portion at one end thereof and means on said rock -shaft moun'ted fornwinging movement and adapted to 'engagesaid off-set portion whens'aid means is positioned at one side of the plunger, whereby thephmger will be depressed agreater distance than when said actuating means is positioned at the opposite side of the plunger axis; said valveniechanism being adapted to restrict the flow of fluid, in one direction, whereby the force required to return the plunger to normal position, will oppose'thereactive force stored in said spring element.

4;. A device for neutralizing the reactive force in a spring eleinentconnectin'g together two relatively movable members, comprising a casing adapted 'to' be secured to one 'ofsaid members, a rock sha'itt insaid'caling havin an operative connection with theothe'r of'said members, fluid chambers in said casing, an inelastic fluid therein, a valve mechanism between said chambers,

chambers, said plunger h aving a"can 1-shaped head provided'with an 'ofl-seit portion, and means on said rock shaft engageablewith said head toc'a use said plunger to beactuated 'onthe plunger head causing thepluu'ger to "be de' re'sised "a meter "distance'when said plungenaetuating means is atonee'ndof Its "relatively movable-member's,- g a easing adapt'ed "to be-secured to one "of said movement thanvvhensaid means is 'a t"theend of its movement, whereby theopera tion of said device may be controlled.

A "device foriieutralizing the reactive cejmasprm ei n ent'eonneenng'to' *mem bers, a' rock shaft in a spring-actuated 1 plunger for circulatingthe fl'u'id between the rocked, the off-set portion members, a rock shaft'insaid casing having 1 an operative connection with the other of said 1nembers,;fluid'chambersin said casing, an inelastic fluid therein, a valve mechanism between said chambers, a spr'ing ac'tuated 'plun'ger for circulating the fluid betweentihe chambers, said plunger having a cam-shaped head provided with an off-set portion, and means on said rock shaft engageable with said head-to cause said plunger to be actuated when said shaft is rocked,-"said valvemechanism permitting free movement of said plunger from normal position"andrestricting its return movement, and the elf-set portion on the plunger head causing the plunger to be depressed a greater-distance WllQHSfllCl plunger-aetuatmg means IS KIt' one end of its IHOVElll'GIlt than when said means is at the other end of its movement, and'w hereby the operation of the device may be controlled.

A-devicefor opposing the reactive force in a springelement connecting together two relatively movable members,comprising a casing ada pted'to be secured to one of said members-a ro'c'k shaft said casing having an -operativ'e coi-inect-ion wit'h the other ofsai-d mein ers, flnid ehambers in said casing-aninelastic fiui'd there'i-n, a valve mechanism between said chambers, a cylinder in the easing open at both ends, s sj 'n-ing-act'uated plunger "operable in said cylinder and "tending to move in a direction towards said constantly rock shiifhtheends of -said plunger being adapted to project beyondthe-en'ds of the cylinder, means on said rock 'shaft engag'eable with the 'plui-iger to control i-ts'movement, said valve mechanism being adapted-torest rict the 1 flow or fluid to retard the return movementof the plunger, and means for ad 3ust i-ng said valve mechanism.

7. A de'v-icefor opposing the reactive "force in a spring element connecting together two relatively movable members, comprising a casing adapted to be secured to one of said said casing having an operative connection with the other of said members, fluid chambers in said casing,

an inelastic fluid therein, a valve mechanism between said chambers, acyh-nder in the casing open at both ends, a spring-actuated plunger operable in said cylinder andconstautlytend'ing to move in a direction'to- "wards said rock shaft,-the ends of'said plungerbeing adapted topr'oject beyondthe endsof thecylinder, means on'said rock shaft engag'eabl'e with-the plunger to controlits-movement, said valve mechanism beinga'dap'tedto *res't'rict the flow of-fluidto retardthe return "inoi ement of the plunger, and-means exteriorly' of fsaichde'vice f r-adjustin said valve mechanism, to varytheforc'e required v id pl'unge'rto norm'ahposition.

V 8. A dev ce foro'p'posing the reactive "force in-a spring element connecting-togetherewe relatively movable members, comprising a in one direction, a cylinder in said casing, a plunger operable in said cylinder for circulating the fluid between said chambers, means constantly urging said plunger in a direction towards said rock shaft, an irregularly shaped cam on one end of the plunger, means on said rock shaft engageable with said cam to cause actuation of said plunger, when said members are moved towards and-away from each other, and a portion of said casing being relatively movable to adjust the operation of said valve mechanism.

9. A device for neutralizing the reactive force in a spring element connecting together two relatively movable members, comprising a casing adapted to be secured to one of said members, a rock shaft in said casing having an operative connection with the other of said members, a cylinder having an annular flange received in threaded engagement with said casing, said flange dividing the casing into two chambers, an inelastic fluid in said chambers, a series of ports in said flange, a valve normally closing said ports, a plunger operable in said cylinder for circulating the fluid between said chambers, means constantly urging said plunger in a direction towards said rock shaft, a cam on one end of the plunger engageable with means on said rock shaft, and the cylindersupporting portion of said casing being adapted for relative rotation to effect adjustment of said valve mechanism, whereby the force required to return said plunger to normal position, will neutralize the reactive force stored in said spring element.

10. In combination with a vehicle including body and axle members having a yielding connection between them, a casing adapted to be secured to one of said members, said casing comprising an upper relatively fixed section and a lower section adj ustably secured thereto, a rock shaftin said upper section having an operative connection with the other of said movable members, a cylinder mounted in the lower casing section and having an annular flange suitably secured thereto, a plunger operable in said cylinder and cooperating with said cylinder flange to divide the casing into two chambers, an inelastic fluid therein, a high pressure valve sleeve slidably mounted upon said cylinder and having one end of a. spring engaged therewith, an adjusting ring received in threaded engagement with one end of the cylinder and slidably and non-rotatably connected with the upper casing section, means on said rock shaft engageable with one end of the plunger to return the latter to normal position, upon return movement of said movable members from abnormal positions, and said lowercasing section being adapted for rotative movement to relatively adjust said adjusting ring upon the cylinder to vary the tension of said valve spring, whereby the circulationof the fluid in one direction may be controlled to cause the force required to return said plunger to normal position, to substantially neutralize the reactive force stored in said spring element.

11. In combination with a vehicle including body and axle members having a yielding connection between them, a device adapted to resist return movement of. said members after deflection away from a normal relative position, said device comprising a casing adapted to be secured to one of said members, a rock shaft in said casing having an operative connect-ion with the other of said members, fluid chambers in said casing, an inelastic fluid therein, a valve mechanism between said chambers, a plunger for circulating the fluid between the chambers, means on said rock shaft to cause said plunger to be actuated when said shaftis rocked, and a portion of said casing being relatively movable and connected with said valve mechanism, whereby when said movable portion is relatively moved upon the fixed portion of said, casing, said valve mechanism will be adjusted.

In witness whereof, we have hereunto set our hands this 12th day of November, 1927.

GROSVENOR M. CROSS. RODERIC M. GROSS.