US2578828A

US2578828A - Ambulatory invalid chair

Info

Publication number: US2578828A
Application number: US698105A
Authority: US
Inventors: Walter R Nelson
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-09-20
Filing date: 1946-09-20
Publication date: 1951-12-18
Anticipated expiration: 1968-12-18

Description

Dec. 18, 1951 w, R NELSON 2,578,828

AMBULATORY INVALID CHAIR Filed Sept. 20, 1946 4 Sheets-Sheet 1 INVENTOR. WALTER R NELsoN A TTYS Dec. 18, 1951 w. R. NELSON 2,578,328

AMBULATORY INVALID CHAIR Filed sept. 2o, 194e l 4 sheets-sheet 2 EN INVENTOR.

WALTER R NELSON TTYS Dec. 18, 1951 Filed Sept. 20, 1946 w. R. NELSON 2,578,828

AMBULATORY INVALID CHAIR 4 Sheets-Sheet 3 'c E INV R.

WALTER R AIE/ 50N Dec. 18, 1951 w. R. NELSON AMBULATORY INVALID CHAIR 4 Sheets-Sheet 4 INVENTOR. WALTER R NELsoN TTYS Filed Sept. 20, 1946 VAS Patented Dec. 18, 1951 UNITED STATES PATENT oFFlcE Walter RfNelson, Elmhurst, Ill. Application September'20, 1946, Serial No. 698,105

6 Claims. (Cl. 280-266) This invention relates to improvements in ambulatory chairs and in particular to that type of chair which is adapted for use by invalids to propel themselves from place to place.

Heretofore, ambulatory chairs have been provided for invalids who are totally incapacitated physically and must be pushed from place to place by an attendant. Another type of chair has been marketed for the usev of persons who have the use of their arms and are able to propel themselves thereby. A third type of chair provides for steering the moving chair' by movement of the occupants body. Each of these chairs have been designed to help overcome a certain physical handicap and are consequently limited in their scope of application.

In this invention there is provided an ambulatory chair which may be used as an ordinary wheel chair under the carer of an attendant, or may be propelled 'and steered by the occupant.

Steering is accomplished by use of the occupants feet or, if desired, by swaying his back from side to side against a backrest. Propulsion of theV chair may be effected by use of the arms. Means are also provided whereby a one-armed patient may propel himself. This is a distinct advantage over the ordinary wheel chair wherein control of both wheels must be had in order to propel and steer the chair. Also, there is incorporated' `in this wheel chair means whereby the occupant can exercise his arms orv his legs as he sitsV in the chair. Furthermore, in my invention I have provided new and novel apparatus for accomplishing these operations.

It is therefore an object of my invention to provide an ambulatory chair which may be propelled by the occupant by use of his arms or may be used as a conveyance under the guidance ofv an attendant. r

It is another object of this invention to provide a chair equipped with means whereby a onearmed occupant may propel himself.

It is a further object of this invention to provide a chair wherein an occupant may steer the Y Y 2 v changed over-'from one type of operation to the other.

It is another object of this invention to provide an ambulatory Achair that is simple in construction and eicient in operation.

According to the general features of my invention, I have provided an'ambulatory chair having a set of propelling levers which are easily accessible to the occupant by which he may propel himself in the chair without the aid of an attendant. v

`Another feature of this invention is the provision of a set of propelling levers von either side of the chair whereby anA occupant having only one arm may propel the chair.

A further feature is the provision of a series of quick-change locks whereby the alternate methods of propelling the chair and of steering the chair may be quicklyichanged from one method to the other. a

Another and further feature of this invention is the provision of a backrest which will, upon the occupant leaning to rightir left, through a suitable linkage and drive shaft, effect the steering of the front wheels.

Another important feature of this invention is the provision of means whereby the propelling levers may be disconnected so that the occupant may use these levers for exercise of his arms.

Another feature of this invention lies in the provision of means for disconnecting the foot pedals for usel by the occupant in exercising his legs.

A further feature of this invention is the provision of propelling lever arms so connected on the crankshaft in relation to each other that at least one vof the levers will always be in position to propel the chair even though the other lever is on dead-center.

A still further feature of this invention is the provision of arm rests which are adaptable for adjustment` in a vertical direction and removable propelling leverspwhereby, with the arm rests in a lowered position and the removable propelling levers removed, an invalid patient may be easily placed in the chair. l

Another important feature of this invention is the provision of va rear axle to which only one of the rear wheels is vsecured for rotation with the axle, the other wheel floating freely on the axle, thus providing a differential action which allows the chair to'be readily turned and pivoted.

Other and further important features and objects of this invention will be apparent from the disclosures in the specications and the accompanying drawings.

On the drawings:

Figure 1 is a side elevational view of an ambula- Eory chair embodying the features of this invenion.

Figure 2 is a front elevational view of the ambulatory chair illustrated in Figure 1.

Figure 3 is a sectional plan view taken substantially online III- III of Figure 1 .looking in the direction Vindicated by the arrow.

Figure 4 is a sectional side elevation view taken substantially on line IV--IV of Figure 3.

Figure 5 is a fragmentary sectional end view taken on line V-V of Figure 1.

Figure 6 is a fragmentary sectional side view taken on line VI-VI of Figure 2. i

Figure 1 is a fragmentary sectional rear elevation taken on line VII-VII of Figure 4.

Figure 8 is an enlarged fragmentary sectional viewtaken on line VIII- VIIII of Figure 7.

vFigure 9 is a fragmentary sectional rear elevational view taken on line XI- XI of Figure 4.

Figure l is an enlarged fragmentary sectional,

side elevation taken on line X-X of Figure 2.

VIn the embodiment of my invention illustrated in -Figures 1 and 2 there is shown an ambulatory chair comprising a chassis I0 on which is mounted oseat assembly 55 and a back supporting assembly The chassis assembly I0 includes a framework comprising side structural members I I and I Ia, one at either side of the chair, connected together by threecross members |2a, I2b and I2c. These frame members are secured together as by welding. A rear handle member I3 is rigidly secured to'this framework and is disposed upwardly from the rear end thereof. The chassis I0 is supported.

' at its rear end on wheels I4 and I4a which are disposed on an axle I5. The wheel I4 is keyed for rotation with the axle I while the wheel I4a is mounted for free floating action on the axle. Two vertical support members I6 and ISa andv two slanted support members I1'and I1a secured as by welding to the frame members II and I la and disposed at their lower ends about the axle I5 support the frame in spaced relation to the axle.

At its front end the chassis assembly I0 is supported by a steerable front wheel assembly being connected thereto by a support member I9. The' support member I9 is rigidly secured to the vcross member I2b at the center thereof by means of a V shaped support member I9a (Fig. 4) comprising two metal straps secured at the apex of the V to the structural member I9 and at their open ends to the cross member I2b. A tubular member I9b welded to cross member I2a is securedto support member I9 by a strap I9c. .The opening in the tubular member and the opening in the V shaped support I9a provide a passageway for a driveshaft the operation of which will be disclosed hereinafter. Support member I9 is essentially a four-sided structure having an opening in the center and cross braces I9d and I9e connecting the opposite sides.

At is front end the support member I9 is rigidly secured to a bearing cover 43 of the front wheel assembly 20. The wheel assembly 20 cornprises a pair of wheels 2| and 2Ia disposed for rotation on an axle 22. A yoke member 23 is pivotally mounted on the axle 22 and securely attached, aspby press t, to a vertical steering shaft 24/which is keyed to a bevel gear 25. As best seenin Figure 6, a member 26, having two tubular bushing portions 26a and 2Gb disposed at right angles to each other, is adapted to flt inside the yoke 23 and to journal a pivot pin 21 in por tion 26a and the axle 22 in portion 2Gb. The pivot pin 21 is also journaled in opposite sides of the yoke 23. Thus the wheels 2I and 2Ia are mounted for pivoting action about pin 21 as shown in Figure 2. This arrangement affords a knee action effect whenever one wheel passes over a bump or slight obstruction. As further illustrated in Figure, the axle 22 is disposed rearwardly from the center line of the vertical shaft 24 about whose axis the front wheels are adapted I have provided means for locking the shaft 24 to the housing 28 in the form of a quick-change lock assembly 3I. This lock assembly, which iu adapted to be positioned in an outwardly extending cylindrical boss 28h of the housing 28, com-- prises a plunger 32 having two sets of pins 33 and 34 projecting outwardly from its surface. These pins 33 and 34 are disposed normal to the axis of the plunger in spaced relation to each other, the pin 33 being displaced approximately 90 fur'- ther around the plunger 32 than the pin 34. An adapter sleeve 36 having two slots 36a disposed 180 apart is adapted to slide over plunger 32. A coil spring 31 also i'ltsover the plunger 32.

In assembling the lock 3I, the pin 34 is first pressed into the plunger 32. The adapter sleeve 36 is then positioned on the plunger with the pin 34 in the slotSSa. Next, the spring 31 is inserted around the plunger abutting the adapter sleeve 36 and then thepin 33 is pressed into place on the plunger 32. The assembled lock is then positioned in the boss 28h and locked therein by any suitable means, such as, by a setscrew 3B which is adapted to screw into threaded holes in the boss 28h and in the sleeve 3B.

With the lock thus assembled, the plunger 32 will extend slightly into an opening 24a in the vertical shaft 24. The shaft will then be locked to the housing 28. To release the shaft 24 vfrom the h-ousing 28, the plunger 32 is retracted from the opening 24a by means of a knob 39 attached to the end of the plunger. tracted from the opening 24a, the pin 34 will move out of the slot 35a and the pin 33 will cornpress the spring 31. When the pin 34 is completely out of the slot 36a the plunger is rotatedv and then released. The pin 34will then be held on a ledge 36h of the adapter sleeve 36 due to the action of the coil spring 31. The amount that the plunger 32 extends into the opening 24a when the shaft 24 is locked to the housing 28 will always be less than the length of the slot 36a in order that when the pin 34 is pulled out of vthe slot 36a the plunger 32 will be entirely retracted from the opening 24a. Thus the shaft 24 will be released from the housing 28.

In order that the housing 28 be capable of either being locked to the frame of the chair or of pivoting in the frame, I have provided a threaded portion 28e at the upper end ofA the housing 28. A lower retainer member 4|! is screwed into place on the housing 28 and locked thereon by a locknut 4I.. A ball bearing assembly As the plunger is re-V envases 42s le adapted tc be positioned in a recess. 40e-oli the member 4.0. The outer bearing housing 43, which;V as previously mentioned, is-rigidly'fsecu-red. to the support member i9.v of the chassis of the chainis positioned overthebearing 42. on a bear-v ing recess 43a resting onthe outer race or the bearing.. t

The outer'raee of an upper ball bearmg 44y is likewise held ini` a bearing recess 43h of the: hous ing 43,. the inner race of thezbearing` 44? being: disposed in a recess 45av of a retainer member 45 which is screwed onto the housing 28 and locked thereon by-a locknut- 46'. With. thisy arrangement, the housing 28- is; rotatable on bearings Wand. 42' the bearing housing 43.

I A; quick-change.` lock '41 identical tothe lock 3i previously described; is positioned. inlan. out-l wardly extending. cylindrical boss 48e; of the housing 43'. The plunger of this,` lock 41; isadapted to move into an; indentation 28e vof the housing 28 and thus; lock. the housing 281 on the bear inghousing 43 whichx is. an integral part of the chassis lo through. support member i9.' f

Steering byI use of. the feet is accomplished by means of a pair of foot pedals 48 and 48a.- which arerigidly attached on steering bars 49 and 49a respectively to the housing 28' (Figure 2)- These bars are i-ntegral'parts of the housing 28v extending outwardly from directly opposite sides.- of the main housing portion. On. the outer end of each of these bars 'there` is an upright peg 49h over which a support tube 50 adapted to be positioned for pivoting movement thereon. Each foot pedal. 48 andv 48a is pivotally mounted on the tube 50 by means of. a hinge5i, asbest seen in Figure 1.' Extending downwardly from the underV surface of each foot pedal near the forward end thereof. is. a flange 52.. For theV purpose of adjusting thefoot pedals in various` tiltingpositions,. a lever 53 is providedwhich is. pivotally connected at one end to the lower end of the support post 58. At theopposite end. the lever 53 takes the form of an lopenV box 53a through which an adjusting screw 54, which is threaded into the flange 52, is positioned. When the screw 54 is backed oi, .the foot pedal may be pivoted on the hinge i `and the box head 53d of the lever 53 will slide back or forth in relation tothe adjusting screw 54 asV desired. When the correct tilted position of the foot pedal is attained, the adjusting screw is brought down tightly on the box end 53a thus holding the pedal in that position.

Each foot pedal has an upwardly extending ridge 48h at the rear and a pair of upwardly extending pegs 48c disposed at the forward portion of the pedal. The ridge 48D is adapted to receive therein the heel of the occupants foot and the pegs 48e are designed to prevent the forward part lof the foot from sliding oi the pedal.

It is .now apparent that, when the quickchange lock 3| has been put in position to lock the housing 28 tothe steering shaft 24 and the lock 41 has been withdrawn so that the housing 28 is free to rotate relative to the frame, the wheels may be steered by pushing onthe foot pedals, since the pedals are secured to thehousingV 28 and the wheels are attached to the shaft 24.

It is desirablefthat the foot pedals be capable of assuming any pivoted position of. the foot as the wheels are steered by the foot pedals. Usually the occupant of the chairwill .want to4 keep his feet directly forward as he pivots the steering bars 49 and 49a; This is possible in my inbers 51.

venton since the support. posts 5.0; are pivotant.' mounted on the upright pegs. 49h or the: steering bars49 and-49a.Y I have further provided a pair of coil springs 54a and 54h which are secured at one4 end to the housing` 28 and at the other end to support posts 50. As a foot pedal is pushed forward andthe straight ahead position of the pedal' is maintained,` the springl will be slightly elongated. Then when the foot is removed from the-pedal the spring 54a or 54h will return the pedal to a. position perpendicular to the steering bars 4:9. Usually when a Vperson gets into this chair he will have positioned the steering wheels pointing straight forwardly and therefore the fooi;4 pedals will always be in a correspondingly straight forward' position. f

'Itz is to be noted` that if the lock 3l is pulled out so as to disconnect the housing 28 from the shaft 24 andthe lock 41 is likewise pulled outto disconnectA the housing 28v from the frame, the occupant can freely operate the steering wheels without affecting any steering of' the wheels therewith. In this way a patient may effectively exercise his feet and legs while confined to the chair."

Itfis further to be noted that when it is desired that the vehicle be steered by other means, as by the. movement of his back, which will be explained hereinafter, or by an attendant who is pushing the chair, the' lock 3i is withdrawn so. that the shaft 24 is free to rotate in the housing 28. Then if the lock 41 is put into position locking the housing 28 to the frame, the steering bars 49 'and 49a are locked in position and the occu-V pant then has a rigid support for his feet.

The seat assemblyI 55 comprises an upholstered' seat 56 suitably secured to a fabricated support frame including four vertical angle members 51 disposed substantially beneath the four corners ofthe seat 56. Two upper side braces 51a and two lower side braces 58 connect the side vertical members 51, while an upper front brace 59, and a lower rear brace 59av and an upper rear brace 59h are'V disposed between the rear vertical mem- These braces and members are suitably fastened togethery as by welding, to form a rigid structure. The four vertical members 51 prefern ably have a square cross section. Near the lower end of eachmember a cylindrical passageway is 1 provided in which is journalled a pair of longitudinal rods 60 and 80a. The

rods

60 and 60a are.

rigidly fastened at each end in the frame cross members Iza and |20, also passing through the' member l2b. The seat and the seat frame are supported by these rods and may be slid back and'forth thereon.

vThe seat assembly 55 also has a rear, centrally disposed frame member 6l which is secured by a flange portion Bla to the under surface of the seat by means of suitable screws 62. Near the lower end of member 6| a threaded passageway Sib is adapted to receive a threaded rod B3. The rod 63is journalled in the cross brace 2c'and is held against axial movement away fromy the brace I2C by a shaft collar 54 secured to the rod 63 immediately in front of the cross brace l2c by a, setscrew 65 and by a crank 66 which is secured to the rod 63 immediately behind the cross brace I2c by .a setscrew 61. Thus, when the rod 63 is turned bymeans of the crank 66 the member 6l,

in which the rodis threaded will be moved back wardly or forwardly as desired thus moving the entire. seat assembly 55 along the

longitudinal rods

60 and 60a. `A stop nut 68 is disposed near the-endof rod63 to limitthe forward adjustment ofthe seat assembly," ""An arm-rest assembly 10, provided at either side ofthe chair, includes an upholstered horivzontal arm portion 1| secured'to the upper end of a vertical rod 12a by means of a socket plate 13 and secured to the upper end of an inclined rod 12b by means of a socket plate 14. The lower terminal ends of the associated rods 12a and' 12b are affixed together and each of the vertical rods 12d is slidably disposed in a support tube 15. The support tubes are' supported from the sidebraces' 51 by means of support members 51h and 51e. Each vertical rod 12a may be adjustably positioned in the associated tube 15 by means of an adjustable screw 16. Thus each arm-rest 16 may be adjusted to any height to support an injured arm or it may be lowered completely to present easy ingress to the chair. "."As asupport for the occupants back and as a means for steering the chair by use of the occupants back, I have provided a back assemblyv80. This back assembly 8G includes two vertical rod members 8| and 82 secured in longitudinal alignment by cross braces 83. These rods are disposed substantially in a vertical direction.' At its lower end the. rod 8| is bent at right angles and projects forwardly into a cylindrical boss member 6|c of the seat frame member 6|. Therod is journalled in boss Sla passing therethrough to receive, immediately forward of the boss 6|a a crank 84which'is keyed thereon.

As best-seen in Figures 2 and 4, the crank'84 is pivotally secured to a lever 85 which in turn is pivotally connected to a crank lever 86. At its upper end the lever86 is disposed abouta drive shaft 81 which is keyed at its forward end to a bevel gear 88 in mesh with the bevel gear 25 on the front wheel steering shaft 24. At assembly the lever 86 is secured, as by brazing, to a sleeve member 89 whose forward portion is journalled in a cylindrical opening in the seat frame member 6|. The enlarged rear portion of sleeve 89 contains a setscrew 99 by which the sleeve 89 and consequently the lever 86 is keyed to the shaft 81. In normal operation the sleeve 89 is keyed to the shaft and thus when the back support' member 8| is pivoted from side to side in the bearing surface of member Blc, the crank 84 andthe lever 95 will oscillate the lever 86 in a limited angular travel. Since the sleeve 89 and the lever 86 is secured to the drive shaft 81 by the setscrew 99, the shaft 81 will be rotated, thus operating the bevel gear front wheel steering mechanism. Thus I have provided a means for steering the chair by use of the occupants back, an arrangement particularly useful to an invalid whose legs are injured or missing.

Ii it is desired to adjust the seat backward or forward on the rods '60 and 60a, the setscrew 90 is backed out and the adjustment is made by means of the crank 69. Thus the lower end of member 6| which abuts the sleeve 89 on one side and the lever 86 on the other, will move the back assembly and the seat assemblyk back and forth withit. Disposed about rod 8| just before the rod enters the boss 6|c, is a substantially cylindrical member 9| which is keyed or pressed onto the rod 8|. Forward andbackward movement of the member 6 la will also be transmitted to the back support assembly 80 'through the abutting action of member 6|a on this member 9| and on thecrank 84.

Anupper backrest 93 is slidably mounted on the upper end of the support'rods 8| and 82,v by

8 meansof'a tubular mung s4 which is positioned over rod 82 and a lower tubular tting 94a, secured to the lower end of tting 94, which is adapted to be positioned about the rod 8|. A

flange 94h of the fitting 94 is suitably secured tor the back rest 93 by screws 95. The purpose ofv the two

tubular fittings

94 and 94a disposed4 about rods 8| and 82 is to prevent the back rest from becoming cocked to one side. The back rest 93 may be adjusted in a vertical direction by use of a setscrew 96 which is vadapted to lock tting 94 on the rod 82.

In order to most conveniently transmit th swaying movement of the occupant to the back rest 93 for steering purposes, I'have provided two steering arms 91 and 91a which extend forwardly from the sides of the back rest 93 and are adapted to hug the occupants body immediately below either armpit. As illustrated in Figures 1 and 5, a plate 98 is secured by a plurality of screws to the back of the back rest 93. Tubular members 99 and 99a, welded to the plate 98 receive lateral support arms |00 and |0011, which may be adjusted therein by use'of setscrews |0I. At their outer ends the lateral support arms have a passageway in which the forwardly extending steering arms 91 and 91a are held. These arms, 91 and 91a, may be adjusted back and forth in support arms |00 and |0911I respectively by means of the setscrew |03. At the forward end of each arm is secured an oval shaped upholstered pad |04 which ts close to the occupants body. Hence the swaying movement of the occupants body may be efficiently transmitted to the back steering mechanism.'

In instances where steering by the back is not required, it is desirablethat the back support be rigidly held in a vertical position. In this invention this condition is provided for by means of a quick-change lock disposed in a lateral arm 9|a (Figures '7 and 8) of the cylindrical member 9|, which is secured to the horizontal portion of rod 8|. When the back lsteering mechanism is being used, the arm Bla oscillates between two limit screws |06 and'l01 which are adjustably centered. into overhanging arms 6|d of the boss 6|c which is part of the seat frame structure. The quick-change lock |95 is adapted to be secured at the outer' end yof the arm 9|a, as shown in Figures and 8. When the lock is in the withdrawn position, the arm 9|a is free to oscillate between the limit screws |06 and |01, but when the lock is thrown into the locked position, as in Figure 8, the plunger of thelock fits into an opening in the boss 6|c and thus locks the back steering mechanism to the frame.

Propulsion of this ambulatory chair may be effected by an attendant who controls the chair by means of the handle 3 or by the occupant who effects propulsion of the chair through a pair of levers ||0 and Illia, one lever being disposed on either side vof the chair. Near its. lower end the lever |0 is pivoted onthe upwardly extending ear ||b of the support member |.I (Fig. 1) byA means of va shaft ||2 which is journalled in both theear Hb and a bushing memberl I|0a of the lever H9. At its extreme lower end the lever H0 is pivotally connected to a rod ||3 which is mounted for pivoting on a rod ||4.v "A pair of crank arms 5 (Fig. 3) `are also pivotable on the pin H4, one being connected at its otherl end to a crankshaft I6,- and the other being connected at its other lend to va shaft? ||6a aligned with shaft |16. The crankshaft isjournalled in a support member l1 depending from the frame memberll. f

Lever I |a is connected to a crank `rne'chanisni fin exactly Athe same way except 'that the crank arms ||5 associated with the lever H0 lead the crank arms ||5a which cooperate wth'the'lever IIUa by approximately 90. All cranks are, of course, rigidly secured, as by a key, to the same "crankshaft II-G which is supported in the d'ownchair is to be propelled by the occupant, the

driven sprocket |22 'is put into driving engagement with the rear axle i5 by means of a quickvchange lock |24 secured to the axle at a point adjacent the sprocket |22. .The plunger of lock `|24 is adapted to engage in .a holev I22a of the sprocket |22, as seen in Figure 9;

It is apparent that, if the occupant wishes to exercise his arms, without propelling the chair, disconnecting Vthe lock |24 will allow him to work the levers fI-If and 2| Ilfor thispu-rpose.

By means of this apparatus, occupants having two arms may conveniently and, with a minimum of effort, propel the chair by working the levers IIO and IIo and -thus Irotating the crankshaft I6. The inner crank arm I |5 is disposed on the crankshaft IIB approximately 90 ahead of the crank arm I I5a in order that'the chair will never stop on an immovable deadcenter position. If one crank did stop on deadcenter, the other would bein a position for moving the chair.

If the occupant has only-one arm, only the lever on the side -convenient to that armisifurnished. `The lever on the opposite side maybe Aefficiently eliminated since theV crank arms, -although keyed vonto the crankshaft IIS, may be easily removed or not furnished, bengreinov- Vably disposed on shafts' I4 and ||6 by suitable means, as by a key-and cotterv pins, or by a press ht.l In this case, the unoccupied end of the crankshaft would ,be journalle'd in the support bushing Ill, or Illa, andl held against axial movement by some suitable means suchV as a washerand a large cotter'pin.

To eliminate the possibility that the chair will stop on deadcenter when a one-armed occupant is propelling it, there is provided a short arm |25 which may be mounted alongside the longer arm I0. This short arm |25 is pivotally mounted on the rod 2 at a boss section |25a. At its lower end the lever |25 is pivotally secured to a rod |26 which in turn is pivotally connected to a crank arm |21, keyed to crankshaft IIS. The crank arm II5, associated with the long lever l0, leads the crank arm |21 by 90. Therefore, at any point at which the chair comes to rest, either the short arm or the long arm will be in a position to move the chair.

It is to be understood that, if thev intended occupant has two arms, it is desirable that only the longer levers be furnished. If thev person has only one arm, a short and long lever should be furnished on one side only. Since all crank arms are keyed on their respective shafts, any combination of lever arms may be furnished without also furnishing unnecessary mechanisms.

A further feature of the construction of the lever arms I l0 and Ila is the provision of an -uppertubuier Seesen "l1-uber eeen .erm which Vis adapted to telescope into a lower enlarged tubular section IIUc. This feature permits the 'levers to A4be removedand `thus provides, when the armrest 10 has been lowered, .a completely unobstructed opening through which an invalid patient may be placed in the chair. Anadjust- `ing-screw iZIla threaded into section .lfiic is provided to 4hold -the lever II-ISU or illrla 'in vany .desired Yraised '-positin.

vTo Aprevent .the chair from moving when aperson fis getting into or leaving it, I have .provided a fbrake meohanismll which, as illustrated :Figure 4,- -comprfises va lbrake-lever |3| "having ;a knob 132 -di's'posed Within easy Vreach of an'occue- -fpahtof theehain The lever |30 ispivoted on.a pin il-33fsecured `in ithe 'frame member` .|9e. LA tubular member |34, pivotally .mounted on a pin |35 'fdisposed Einv fthe lever il 31, `is :adaptedeito receive therethrough .arrpush rode-|36 WhichzcarriesV a shoulder portion 13Go, Disposedaboutuiihe rod |35betweentheshoulder IBM-andthe tubular member I3liv is a coilspring '13.1. Attheendopposite 'to the brake leverfend, the vrod .I 3621s pivotally Adisposed about a -brake rod E38, which is sour.- `nalled near its ends iin `downwardly .extending arms |139 and 113Go pivotallysecuredtto the'f-rame memberslil and Illa. vl/Then the :brake vlever |31 `is .rotated :counterclockwise about the :pin l:133,- `the tubular .member Ap'ivotallyssecured 'on' pin #|135 moves througharcomfparatively flat `:arc :about fthe .piny |133 1at.center. The spring. |311 is compressed thus pushing the shoulder 2|?3 Ga,. and'consequentlythearod I 3 E, rearwardly.v *The vbrake rod |38 fis thus pressed l:into braking engagementwith fthe' rear Wheels. 'When the rod |38-, thepi'n f|351and the pin 1E33 .arein line, thebrake' 'mechanism-is' onfdead center. As .the lever `Varinflf'il' iis pivoted further, fthe pin..|351is swung foverde'ad center into a :locked position; The spring I3'I` now :acts tofholdthe .lever in this position. The-knob `I321is,=of`v course, within easy reach of fthe-foccupant of the chair,.ev.en in the loekedrfposition; iFrom the .foregoing 'it Iis- :evident that fthereis provided i'n "this invention'a novel type of arnbulatoryeohair-that isadapted 'for-use', vnot only by Apersons' who are :recovering-'from illnes's,fbut

also by those .who are incapacitated, vevenftoithe extent.of-lhavinglostbothatheir legs and -an arm; It wilLrUf Acrourse, be understood :that various details' `lof =con`struction :may be varied througlfrot a wide range without departing from the principles of this invention, and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the -appended claims.

I claim as my invention:

1. An ambulatory chair comprising a pair of rear wheels, a pair of steering wheels disposed forwardly from said rear wheels, a rst axle journalled in said rear wheels, a second axle journalled in said steering wheels, a slidably ad- .instable frame structure, means supporting said frame structure on said rst and second axles including a steering yoke member through which the second axle extends, the yoke member being pivoted on the frame structure for movement about a generally vertical axis, a steering assembly responsive to themovements of the occupants back, said steering assembly comprising an upright arm pivotally supported in said frame structure, a crank mechanism actuated by-said arm, a drive shaft disposed for rotation by said crank mechanism, a rst gear secured to said 11' shaft, a second gear enmeshed with said first gear and secured to said steering yoke member for rotating of said front wheels about the generally vertical pivotal axis of the yoke member.

2. An ambulatory chair comprising a support structure, front and rear Wheels supporting said structure, a shaft secured to said front wheels and journaled in said structure affording a vertical pivot axis for said front wheels, a rod journaled on said support structure and in driving engagement with said shaft, a seat assembly slidably mounted on said structure for adjustment longitudinally thereof, an oscillatable mechanism having a crank arm adjustably slidable on said rod and normally keyed to the rod for oscillating the rod to effect oscillation of said shaft, and guide members pivotally mounted on said structure and arranged to fit closely on either side of the body of the occupant of said seat and connected to said arm, said crank arm being adjustable longitudinally of the support structure by abutting contact of said seat assembly upon adjustment of the seat assembly.

3. An ambulatory chair comprising a rigid support structure, front and rear Wheels supporting said structure, a shaft secured to said front wheels and journaled in said structure affording a vertical pivot axis for said front wheels, a rod journaled on said support structure and in driving engagement with said shaft, a seat assembly slidably mounted on said structure having an upright support member disposed intermediate the side edges of said seat assembly and depending therefrom, an oscillatable mechanism mounted on said seat -assembly and including a crank arm slidably adjustable on said rod and normally keyed thereto, and collars on said crank arm on either side of said depending support member, said crank arm being slidable on said shaft by abutting contact of said member with one of said collars as said seat is adjusted.

4. An ambulatory chair comprising a support structure, front and rear Wheels supporting said structure, a shaft secured to said front wheels and journaled in said structure affording a vertical pivot axis for said front Wheels, Va rod journaled on said support structure and in driving engagement with said shaft, a seat assembly mounted on said structure, an oscillatable arm connected to said rod for oscillating the same to effect oscillao tion of said shaft, guide members arranged to fit closely on either side of the bodyof the occupant of said seat and connected to said arm, and means for limiting the range of oscillating movement of said arm.

5. An ambulatory chair comprising a support structure, front and rear wheels supporting said structure, a shaft secured to said front wheels and journaled in said structure affording a vertical pivot axis for said front wheels, a rod journaled for rotation longitudinally of said support structure, a seat assembly slidably. adjustable on said structure, an oscillatable crank mechanism connected to said rod and having a portion journaled for oscillation in said seat assembly and secured against longitudinal movement relative to said seat assembly, an arm extending transversely of said portion adjacent said seat assembly, and an abutment arm secured to said seat assembly and projecting outwardly on either side of said arm to limit the range of oscillation of said arm.

6. In an ambulatory chair of the type wherein a frame structure is mounted on rear wheels and steerable front wheels, the improvement which comprises a generally vertical steering shaft ccnnected to said front wheels and journalled in the frame structure for rotation about its generally vertical axis, foot actuated levers, locking means for connecting said levers to said shaft for rotating the same, an oscillatable back rest, a lever mechanism connecting said back rest to said shaft to cause oscillation of said shaft when said locking means is disengaged.

' WALTER R. NELSON.

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

UNITED STATES PATENTS Number Name Date 216,203 Marx June 3, 1879 221,917 Hassenpflug Nov. 25, 1879 422,087 Loser Feb. 25, 1890 502,866 Schmiedel Aug. 8, 1893 607,500 Brinton July 19, 1898 1,327,960 Moody Jan. 13, 1920 1,503,878 Brady Aug. 5, 1924 1,987,331 Floraday Jan. 8, 1935 FOREIGN PATENTS Number Country Date 456,498 Great Britain NOV. 10, 1936