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Publication numberUS2615499 A
Publication typeGrant
Publication dateOct 28, 1952
Filing dateDec 27, 1950
Priority dateDec 27, 1950
Publication numberUS 2615499 A, US 2615499A, US-A-2615499, US2615499 A, US2615499A
InventorsDe Loss D Wallace
Original AssigneeGen Motors Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 2615499 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

OCt. 28, 1952 DE LOSS Q WALLACE 2,615,499

HYDROTILT 2 SHEETS-SHEET 1 Filed D eC. 2'7, 1950 /NVE-A/Toe DELossDJA/MLAO- Oct. 28, 1952 DE LOSS D. WALLACE 2,615,499

HYDROTILT 2, SHEETS-SHEET 2 Filed Dec. 27, 1950 Patented Oct. 28, 1.952

.2,615,499 HYDROTILT De Loss D. Wallace, Dayton, Ohio, assignor 'to General Motors Corporation, Detroit, Mich., a j corporation of Delaware Application December 2,7, 1950, Serial No. 202,835

10 Claims.

This invention relates to improvements in adjustable lounge chairs.

It is among the objects of the present invention to provide an adjustable lounge chair which may be 'tilted into the desired .position by the application of a predetermined tilting force, the chair being ymaintained in thev adjusted tilted po*- sition when the required 'tilting' force is reduced or discontinued.

A 4further object of thepresent invention is vto provide a lounge chair, capable of being tilted into the desired position vby the application-of a predetermined tilting force. 'with modifying means operative to vary the required force to tilt the chair, 'whereby the .chair may readily be kadjusted for practical and comfortable use by tofshow structural features, the mechanism being inthe normal position.

Fig. 2 is a view similar to Fig. 1, however, showing the position of the'mechanism when the chair has been tilted.

Fig. 3 is a diagrammatic. .view illustrating the hydraulic connections between the various pedestals of the chair.

Fig. '4 is a view similar to Fig. 2, however, illustrating a modified form of fluid .displacement mechanism.

Fig. 5 isa view similar to Fig. 1, however, show' ing a modified form of complete tilt control mechanism illustrated in la normal position.

Fig. 6 illustrates the tilt control mechanism of Figrinthe position when the chair has been tilted.

Fig. 7 is adiagrammatic view of the complete hydraulic and mechanical connections of elements embodied in the structure illustrated by Fig. '5- L Fig. 8 is a fragmentary', detailed view of the pivotalmounting'method of certain .levers of the device.

Fig. 9 is `a schematic sectional 'view of a. fluid flow control valve used in the present, invention.

Themechanism or device forming the subject matter of this invention may be applied to any 22. The base 20g-has a sleeve receptacle Y23 Asecured vat each `corner thereof. These receptaclesl are in the form of asleeve in which a foot 'or pedestal is slidably carried. The front pedestals, or more particularly the pedestals at the two front corners of the rectangular frame, are designat'ed by vthe vnumerals 25 and the pedestals supported at the two rear corners of the rectangular frame are designated by the numerals 26. lEach pedestal hasarounded end'adaptedto rest upon the iloor, the opposite ends ofthe pedestals being open. lIn each pedestal 25 there isA provided a piston 2l shown 'in .the present. in* stance to beringeshaped. A similarpiston 28 is contained in each. pedestal 26; A tubular ypiston rod 29 is securedin the central opening of ringshaped .piston 21, the other end of said rodrb'eing closed by a .plug 3'0 which is anchored to the side of the `frame 20 supporting the respective ped`v estal 25. Fig. 1 shows the interior of the right front pedestal 25 beneath the piston 21 to be in' communication with the interior of the hollowV piston rod 29. Likewise, a hollow piston r'rod 3| has its one end secured within the central open'- ing of .piston 28,.,a plug `32 closing the opposite. end of the rod 3l and anchoring said rodrto the side of the chair frame '20 in which 'the right rear pedestal 2S is slidably supported. It will, of

course, be understood that the left front pedestal- 2t5 at the opposite front corner of the chair frame` 20, aswell as theleft rear pedestal have-similar piston and piston rod constructions, the piston. rods at this oppositegside of the frame being .1anchored to the adjacent or opposite side member of frame 20. k r

It will be seen that the two pedestals at each, side of the chair are hydraulically interconnected, the pedestals 25 and 26 at the'right Vsideof the chair, by the conduits 35R, and Iii-ilrtthefl pedestals 25 and 2,6 at the left side of they chair by the conduits 35L and 35L. Conduite 35B; andy 3BR communicate with opposite, sides of .a normally closed, two-way nuid flow control device or valve 3'lR. A similar valve 31Li`s interposed.,

between. the. conduits 35L and 361i. YA type of thesev valves 31L and 31B. isdetailedly illustrated. in Fig. 9 as being yieldable, vnormally closed Yand capable, in response to 'a predetermined pressure, to be opened for establishing a restricted fluid` flow therethrough in one direction or the other to permit uid transfer between the respective pairs of pedestals -25. Each valve is provided with a mechanism for modifying the fluid flow control characteristics thereof, a single element 4U being connected with both mechanisms for simultaneously adjusting them so that both provide the same huid flow control. One kind of `valve 3`|R or ETL which may be used in the present invention is schematically shown in Fig. 9 in which pipes 35B and BGR communicate with the interior chamber in the valve casing, Two valves |8| and |82 are yieldably urged against the respective end walls of chamber it normally to shut off said communication of the pipes with the chamber. A duct |86, normally closed by the valve l 8| in its normal position provides communication between chamber |89 and the pipe 3BR when pressure hasmoved valve |8l from its seat. A similar du'ct I9 normally closed by valve |82 leads to pipe 35B. andy connects chamber |80 with pipe 35Rwhen valve |82 is unseated by fiuid pressure in pipe 36B. Actuating element 49 is attached to a rod 283 which extends into and throughchambers |85 of both valves 31B, and 3l, said rod having a cam |845 attached thereto in each valve chamber. This cam is engaged by abutments |85 and |86 which are moved apart by operation of the cam to compress springs |81 and |88 againstthe respective valves |8| and |82 to urge them upon their seats with greater pressure. Actuation of the cam |84 will also permit said springs to expand and thus exert lesser pressure upon their respective valves. Thisvaries the resistancetothe transfer. of fluid betweenthepipes 3ER and SGR and L and 36L in 'either direction. The Figs. 1 and 2 clearly illustrate the aforedescribed device, the'Fig. 1 showing the chair in its normal or level position, When the user desires to tilt the chair backwardly, pressure is exerted against the frame 20 and particularly the back rest 22 thereof causing the rear pedestals 2S right and left to be forced inwardly of their supports 23. This -inward movement of the rear pedestals 25 results in fluid displacement from said pedestals to their associate front pedestals, fluid being displaced from the rear right pedestal 26 through conduit 3ER, exerting a pressure upon the valve 31B, to open and establish a restricted flow through conduit 35B into the. interconnected pedestal 25 at the front of the chair. Similarly fluid displaced from the 'left rear pedestal 26- ows through the conduit 36L against valve 3'5L, opening said valve to establish the iiow through the conduit 3.5L into ther pedestal 25 at the left front side of the chair. VIt will be understood that the valves STR and 3`|L are adjusted to open at the same predetermined pressure exerted thereagainst. As long as the predetermined tilting force is applied to the back rest 22 of the chair tilting movement of .the frame will obtain. However., when Isaid tilting force against the backl rest 22 is reduced below the predetermined fixed value or is discontinued, then the chair will be maintained in the adjusted tilted position and, upon reduction of fiuid pressure against valve 37, said valve-will close and thus stop any fluid transfer between the front an rear pedestals. Y

If the valves 31B. and 3`|L 4are adjusted initially to require a substantial high fiuid pressure for opening them, it would be difficult for a person of small stature or a child to exert sufficient force or weight against the chair frame to cause or'light weight person or by a larger or heavier person. If a child desires to use the chair and Yfinds it is improperly adjusted, the modifying device actuator 4U is operated to adjust valves STR and BTL so that a lesser fiuid pressure is required to open them. On the other hand, if a yheavier person desires to use the chair and finds it is too freely tltable the actuator i may be operated to modify the control characteristics of the valves so that a Igreater fluid pressure is necessary to open them for establishing the fluid transfer which is necessary tol permit `tilting of the chair.

If both front and rear pedestals l25 and 26 are.V cf equal size then the chair Will tilt about a point,

substantially midway therebetween and thusthe. front of the chair seat supportingthe limbsof the user beneath the knees will be raised adistance substantially equal to the lower movement of the rear rportion of the seat. In vsome instances this may cause inconvenience inasmuch as the original design of the chair provided for proper height for the limbs of the user. Injorder that the front portion of the seat be maintained substantially aticonstant level even though the chair, be tilted backwardly as shown Fig. 2, the rear? pedestals 26 may be predeterrninatelysmallerin;y

diameter and therefore of lesser fluid capacity than the two front pedestals 25. Thus a complete collapse of the smaller rear pedestals 26 would displace an amount of uid which when transferred to the larger front pedestals 25 would cause very little outward movement thereof and thereby the normal level of the frontportion of the seat would be maintained. Contrariwise, if it is desired to effect greater movement of the front portion of the seat than the rear portion thereof, the front pedestals may be vof smaller fluid flow capacity than the rear-pode' estals.

The construction shown in Fig. 4 i-s a modification of that shown in Figs. 1 and 2. Here, instead of fluid being contained` within the pedestal itself, a closed expansible and contractableelement, preferably a bellows, is housed within the pedestal which now is not a fluid container but a housing for the element which contains the fluid. The bellows in the front pedestals are designated by the numeral 45 and the rear pedestals by the numeral 46. Fig. 4 illustrates the two pedestals at the front and rearright side of thel chair. Each bellows has a tubular extensionsecured thereto, the closed end of the bellows resting against the closed end of the pedestal, vthe opposite end of the bellows having the communieating, tubular extension provided thereon. Bellows 45 has a tubular extension M which has a plug 49 at its outer end closing the extension` and anchoring it toward the side of the frame of the chair. Bellows 45 seated in the pedestal 26 at the rear of the chair, has a tubular extension.

48 provided with a closure cap 5|] which anchors the extension 48 to the side of the chair to which tube 47 is anchored. An adjustable, normally closed valve S2 has one side connected to the tubular extension 41 by meansv oia 'conduit 760, a similar conduitl connecting the opposite side ofthecontrol valve 62 with the tubularextension 48. It will.Y be understood that this same mechanism'is duplicated at vthe yopposite side of the chair. A l

Th'eaforedescribed mechanism operates as follows: When a predetermined and necessary force is exerted upon the chair and particularly its backrest 22 to urge the pedestal 26 inwardlyof its 'support, bellows 46 is collapsed, displacing flui'dthrough the tube 48 and `conduit 6| and exerting uid pressure upon the valve 62 which, at'a'predetermned pressure, will open to establisharestricted transfer of uid from conduit `6| to c'onduit 60 'and thence vthrough the tubular "extension 41 into thegexpanding bellows v45. The mechanism at theoppositeside of the chairwill functioninthe same manner. Thevalves`62jof the mechanisms at bothY sides of the Achair are each provided with a modifying device adjust'- ableconcurrently byfan actuator `similar to 'the actuator 40 "as in the vdevice shown in'Figsl land 2. 'By means of the adjustment of the Va1ve'62 the action of these valves may be 'modied to require either lesseror greater fluid pressure to open said valves thereby rendering the Achair usable by either persons of small stature or g'reate'rcorpulence respectively.

Figs. 5, 6, 7 and '8, shown on the second sheet of drawings, illustrate a modied 'form of tilt controlmechanism. In this type of construction, no ui'dis contained in the pedestals 'of the chair but on the contrary, iiuid displacement element-s are .provided and mounted upon each side member 'of 'the frame. Inthisv modiiied construction, the're'spectve front and rear pedestals |25 and |26 are slidably supported in sleeves lsecured at thefour cornersof theirame |20. A lever |21 is' pivoted substantially at its center to the one side of the frame, one end of said lever being secured to the front pedestal |25, the other end to the rear pedestal |26 at saidoneside of the chair frame; As shown in Fig. `7, the opposite front pedestal |25a is secured to one end of la lever |2`la, the other end of said lever being attached tothe other rear pedestal '|26a. Thus when one pedestal, for instance, the pedestal |26 is moved inwardly of the frame, leverl 21 movingicounterclockwise about its central, pivotal support as re- 'gards Fig. 7, will urge pedestal |25 outwardly of the frame. The pedestals at the opposite side of the chair -act in va similar fashion when the necessary force is applied to the chair to urge the rear pedestals inwardly of the frame.

This type of Yconstruction provides two separate fluid displacement elements, one at each s idelofV the chair frame. The uid displacement element associated with the pedestalsl |25 and |25, consists of ga cylinder |28 secured to the right side of the chair frame, said cylinder having apiston |29 which divides -the cylinder yinto twouid'containing compartments |30 and |'3|. A piston rod -attached to piston |29 extends through the cylinder chamber |3| and the one endfhead of the cylinder to-the exterior thereof. This piston rod-designated by the numeral |32, vhas{itsfouter'en'd operatively secured to one end Oa'right angled lever |33, which'is pivoted at thepoint |34V tothe side ofthe frame supporting the'pe'destals |25 and"|26 and also the cylinder |28. The opposite'angular arm of saidlever is secure'dto therear pedestal |26. Thus Vit may befseen that lactuation'of the pedestal y`|2|5`will operate'the piston |29'toward the'leftasv regards 'chair frame.

|43. V'eisten m vhas a 1rod-141| securedftherto;

extending through cylinder chamber |43 Vlto lthe exterior' ofthe fluid displacement member, the outer end'of -this rod "|44 `being 'operatively :fsecure'd to 'o"ne-arm nof afright v'angled lever 1h45 which ispivoted -at |46 fto said left'side lof the' The fopposi't'e y-arm of thisglit angled lever |45 is `operativelyconnei'stedto the front pedestal `|2 Saat the' left fifront iside-of the chairffr'a'me. n y This mecnalnism hasta unitary, .two-'waypres--v sure contrl valve .|50 of any :suitablefstandard design, .provided with any *suitable Vmaximally cp--` i eiable-modif-yingi device r|5 which `maybe actuated to change 'the .controlcharacteristics "of this valve. This valve 'mechanism .is normally'closed to preventnuid ow 'therethroughbut mayffibe actuated at a predetermin'edfluid pressure'tobe opened 'and establish :a restricted owaofuid therethrough inone direction or'the other.;.;2i conduit |152 Aprovides communication :between the chamber |3| of cylinder |28 with onefsi'denf the valve and 7a similar conduit |53 .providescommue nication'. :between the same side ro'f. valvev @|50 :and

the chamber |42 .ofthe cylinderzorfluid displace v ment Eme'mber |40. Another conduit |54 'connectsthe opposite side of the valve with the chamber |30 of the fluid displacement cylinder |28-Janda conduit |55 connects this same sideiof the valve with the chamber |43 of the .uidrdise placement cylinder |40. The connections ofthe conduits, just mentioned, -With the valve .and .the channelswithin the valve |50 lare such that, when the valve'is opened, conduits 53 and |54' in communication with each other `andconduits |52 and |55 will be in communication.

r4This type of construction operatesi-n =the` `following manner:

When -a suflicient tilting force is applied tothe frame |20 of the chair, or more particularly, the back rest |22, for instance, to .tilt the 'chair backf Wardly into the position -as shown in Fig. 6, the

pedestals |-25and .|26a will be urged inwardlyof the frame. This .movement `of ,pedestal |26 through its lever connections withthepistonzrod .|32`v-urges the piston |23 to the left asregards Eig; -.7.While.the inward movement `of pedestal .|26a into the frame Will ycause the lever |45 .to

I actuate the .piston |4| in cylinder |40 r"also Lto- |22 of the chair, the Valve`|50 will be opened,

thereby establishing a transfer of 'fluid from chamber |30 through the valve |50 `and v"conduit |53 into the chamber |42 ofcylin'der |4`0,'cham-' ber |42, and chamber |30, being the rod 'free chambers of the respective cylinders and thus of equal fluid displacement capacity per unit of piston movement. Likewise, fas the -piston .|-4.|

moves to displace -iiui'd vin chamber |43, thevalve 7 |50, opening at the predetermined pressure, will permit the iluid to flow through the valve into the chamber |3| of cylinder |28, these two chambers |3| and |43 being the rod containing chambersand of like fluid displacement capacity per unit of piston movement. As soon as the tilting force upon the chair frame, and more particularly, the back rest |22 thereof, is reduced or discontinued, fluid flow through the valve |50 will be discontinuedv due to the closing of theV Valve in response to a decrease in fluid pressure thereupon and thus the chair will be maintained in the adjusted tilted position. As in the case of themechanism shown in Figs. 1 to 4 inclusive,-

this type of mechanism may be adjusted by manualoperation of the modifying device |5| to be adapted for use by either small, light weight persons or persons of greater corpulence. In any of the constructions illustratedjand described the chair may be adjusted tiltably forward and backward but the mechanism prevents any tilting side-Wise or diagonally.

l 'From Vthe foregoing, it may be seen that the present invention provides automatic means which permits adjustable tilting of a lounging chair forward and backward but not sidewise upon the application of a predetermined tilting force` applied thereto, said mechanism holding the chair in the. adjusted position when said tilting force is reduced or discontinued. The mechanism is also adaptable to be adjusted, rendering the chair practically and comfortably usable by either a person of light weight or a larger and heavier person. The complete mechanism is so designed that it may be assembled Within the frame of the chairand completely hiddenthereby, in no way effecting the outward appearance of the chair.

- While the embodiment ofthe present'inven-l tion as herein disclosed, constitutes apreferred form, it is to be understood that other forms might be adopted.

What is claimed is as follows:

- l'. 'A'chair adapted to be adjustably tilted by the application of a predetermined tilting force applied thereon, said chair being maintained in the adjusted position when the required tilting force is reduced or discontinued, comprising. in combination, a; frame providing a seat and a. back support; two `independent pairs of interconnected pedestals, each pair consisting of a front and rear pedestal movably carried by the frame; hydraulic mechanism-associated with and operatively cnnecting each pair 'of pedestals;A and normally closed fluid flow control means for said hydraulic transfer'only in response to said predetermined tilting force applied to the frame.

3. A chair adapted to be adjustably tilted by' a fluid flow control device in said fluid transfer mechanisms, operative, when said predetermined tilting force is applied to the frame of the chair, for permittinga controlled transfer of fluid between-the two oppositely moving pedestals of each pair.

f 2. A chair adapted to be adjustably -tilted by the application of a predetermined tilting force applied thereon, said chair being maintained in the adjusted positionwhen the required tilting force is reduced or discontinued, comprising in combination, a frame providing a seat and a yback support; a pedestal movably secured to the frame adjacent each front and rear corner thereci; a uid'transfer means operatively connecting a front and rear Ypedestal on the frame and operative to transfer fluid therethroughin either direction in response to movement of the respective pedestalsrelatively to the frame; and fluid flow control mechanism for permitting such fluid mechanism, operative only in response to said predetermined tilting force applied to the frame, for permitting fluid flow through saidmechanism.

4, A device in accordance with clairnl, char-` acterized by the fact that the uid flow control means is provided with a modifying means operative to alter the flow control characteristics of said control means in accordance with the desires of the user. v

5. A device in accordance with claim 2, in which, however, said fluid flow control mecha.- nism is provided with modifying means operative to adjust the said mechanism to decrease or increase its restriction to fluid ow whereby a reduced or increased tilting force is required to establish a fluid ilow through said mechanism for permitting tilting of the chair.

6. A chair adapted to be adjustably tiltedby the application of a predetermined tilting force applied thereon, said chair being maintained in the adjusted position when the required tilting force is reduced or discontinued, comprising in combination, a frame providing a seat and a back support; a fluid displacement device provided at both front and both rear corners of the frame, each of said devices consisting of a cylinder closed at the outer end and slidably carried by the frame to form a pedestal for the chair and a hollow piston in the cylinder, the outer end of the piston being closed and anchored to the frame; separate conduits, one lproviding communication between the hollow pistons and their respective cylinders at the front of the frame, the other conduit providing communication between the hollow pistons and their cylinders at the rearof the frame; and a normally closed, two-Way iiuid iiow control device connected between said two conduits, said control device being operative to permit a transfer of fluidA between. the two front and the two rear uid displacement devices in response to a predetermined tilting force being applied to the frame of the chair.

7. A chair adapted to be adj ustably tilted by the application of a predetermined tilting force applied thereon, said chair being maintained in the adjusted position when the required tilting force is reduced or discontinued, comprising in combination, a frame providing a seat and a back support; a pedestal slidably carried at both front and both rear corners of the frame, each pedestal being tubular with its outer, floor engageable end closed; an expansible and con- .tractible fluid container in each pedestal, each container having a rigid, tubular extension the closed outer end of which is anchored to the frame; separate conduits providing communication `between the two front and the two rear fluid containers; and a normally closed, two way valve connected between the two conduits, said valve being operative to open communication between said conduits and permit fluid displacement between the front and rear iiuid containers in response to actuation of the respective pedestals by the application o a predetermined tiltin force upon the frame of the chair.

8. A chair adapted to be adjustably tilted by the application of a predetermined tilting force applied thereon, said chair being maintained in the adjusted position when the required tilting force is reduced or discontinued, comprising in combination, a frame providing a seat and a back support; a pedestal slidably supported in the frame at each of the front and rear corners thereof; two levers, each centrally pivotally secured to the frame, the ends of one lever being secured to the respective front and rear pedestals on one side of the chair frame, the ends of the other lever being secured to the respective front and rear pedestals at the opposite side of the chair frame; two iiuid displacement members each secured at a respective side of the chair frame, each member consisting of a closed cylinder having a piston forming two chambers there in and a rod attached to the piston and extending through one of said chambers and a cylinder end to the exterior of the cylinder; two levers, each pivotally secured to a respective side of the frame, the one end of each lever being connected with one pedestal, the other end to a piston rod at the same side of the frame; a conduit connecting the rod containing chambers of both cylinders; a second conduit connecting the rod free chambers of both cylinders; and a normally closed fluid flow control valve in each of said conduits, operative to permit the transfer of fluid between the rod containing chambers and the rod free chambers of said cylinders in response to the actuation of the chair pedestal connected to 10 the piston rods of said cylinders, by application of a predetermined tilting force upon the frame of the chair.

9. A device in accordance with claim 8, in which, however, said fluid flow control valves are provided in a unitary structure having a moditying device manually operable concurrently to adjust said valvesfor varying the force required to tilt the chair and establish uid transfer.

l0. In combination with a tiltable chair having a frame; fluid displacement means supported in the frame and providing front and rear pedestals operative by tiltingl the chair; a normally closed, two way valve operative at a predetermined uid pressure to permit a restricted iiuid flow therethrough in one direction or the other; conduits connecting the uid displacement means at the front of the chair with one side of the valve and the fluid displacement means at the rear of the chair with the other side of the valve whereby restricted transfer of iluid between the said front and rear displacement means is effected when a predetermined tilting force is applied to the chair to actuate either the front or rear pedestals; and means accessible to the chair user for modifying the control characteristics of the valve.


REFERENCES crTEn The following references are of record in the iile of this patent:


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U.S. Classification297/325, 297/330, 297/344.16, 297/344.12
International ClassificationA47C1/024, A47C3/30
Cooperative ClassificationA47C3/36, A47C1/029, A47C1/0244
European ClassificationA47C3/30, A47C1/024B