CA1186207A - Wheelchair construction - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A wheelchair capable of being constructed in several different sizes from components of standard size in order to permit users of different sizes and users with one or more handicaps to utilize such wheelchairs. The wheelchair includes a main frame and a foot support assembly which can be telescopi-cally adjustably affixed to the main frame. In addition, a seat section can be telescopically adjustably affixed to the main frame such that the seat is located at a selected height and the foot support section can extend outwardly from the frame for a selected distance to accommodate users of differing height. The rear wheels are positionally mounted with respect to the main frame such that the rear wheels can be located in several different positions in order to change the overall center of gravity and the wheelbase of the wheelchair. In this way, the wheelchair can be used for conventional wheelchair movement, as well as for athletic activities. A pair of front wheels are also adjustably positionally mounted with respect to the main frame in order to change the angle of the wheelchair and the seat relative to the ground or other supporting surface.

Description

1 ~ TION

2 1. Field of the Invention

3 This invention relates in general to certain new and use-ful improvements in wheelchairs, and more particularly, to improved wheelchairs which can be constructed in a variety of sizes from 6 standard size components and which also h~ve front and back wheels ~ adjustably mounted -thereon.
8 2. Brief Description of the Prlor ~rt 9 Wheelchair constructions have remained unchanged, except for relatively minor features, for a substantial period of~time.
11 While wheelchairs have existed fox many years, -they generally were 12 constructed of a main frame, front and rear wheels, side rails 13 or so-called "arm rests" and foot support members. However, there 14 was no means for creating or manufacturing a wheelchair of differ-ent sizes, at a relatively low cost, from standard sized compo-16 nents, in order to accommodate dif~erent size,~sers.
17 Prior axt wheelchair manufacturers constructed several 18 different sized wheelchairs and used different sized components 19 for each of the differently siæed wheelchairs. In the case of a tall individual, the main frame had to be larger, the seat 21 located in a different posi-tion, and a foot support member 22 extended further from the seat, than in the case of a wheelchair 23 for a smaller individual. In addition, for the larger sized 24 wheelchair, the seat may have to have been located at a higher elevation in order to permit the user to engage rims on the 26 wheels for propelling the wheelchair in an easy and convenient 27 manner.
28 Notwithstanding, heretofore there has not been any 2~ wheelchair which is designed for anything except normal txansport.
In other words, wheelchairs heretofore cons-tructed were not 3~ designed to permit any form of athle-tic activity, and particularly, ~ ~3-1. i ~ '7 1 ¦ for fast-moving sports activities. This was primarily due to the 2 ¦ fact that the prior ar-~ wheelchairs were all of a box-like ~ ¦ construction wi-th the seat, and hence, the center of gravity,

4 ¦ located at a fixed and at a substantial distance above the ground.

5 ¦ Consequently, the prior art wheelchairs were not designed for any

6 ¦ fast movement, and if one attempted to propel any of the prior art

7 ¦ wheelchairs at any significant speed, or attempted to turn a corner ~ ¦ quickly, the wheelchair might well tip over creating injury to the 9 ¦ user.
10 ¦ In recent years, it has been found to be highly beneficial 11 ¦ for paraplegics and others required to use wheelchairs Oll a rela-12 ¦ tively permanent basis to engage in various forms of athletic 13 ¦ activities, including wheelchair racing, tennis, and the like. How-~4 ¦ ever, the wheelchair constructions ~heretofore did not lend them~
15 ¦ selves to such form of activities.
16 ¦ For the more seriously handicapped people, particularly with 17 ¦ high level back injuries which limited the mobility of these handi-18 capped persons' arms, the conventional wheelchairs are difficult to lg ¦use. This is due to the heavy construction and weight of the con-20 ¦ven-tional wheelchairs which make it more difficult for the injured 21 ¦party to push and -to manuever. As a result, people with such injur-22 ¦ ies had to resort t~ the use of motor powered wheelchairs, as for 23 ¦example, electric motor powered wheelchairs which use a battery 24 ¦source of power. These motor powered wheelchairs are quite expen-~5 ¦sive and require periodic maintenance which thereby militates 26 ¦ against widespread use. Further, these wheelchairs require frequent 27 ¦ recharging when battery powered.
28 ¦ U. S. Patent No. 3,937,490 to Nasr discloses a wheelchair 29 ¦ having some degree of adjustability to suit several body sizes and 30 ¦deformities. Particularly, the width of the seat and back rest 31 ¦ panels may be adjusted, and the length of the seat may be adjusted.
32 ¦ However, this patent does not dislcose a wheelchair which can be _.~

11~ ?,1)'7 ~ ¦ made from a common main frame and in a variety of commonly sized 2 ¦ components which are capable of being mounted in a desired location 3 ¦ in the same manner as taught and claimed in the instant application.
~ U. S. Patent No. 4,046,374 to Breyley discloses a walking aid which 5 ¦ includes caster wheels. In addition, the walking aid is provided 6 with telescopically located adjustable members.

8 ~

11~

28`

32 l ~4A-b'~

¦ OBJECTS O~ TE~E INVENTION
¦ It is, therefore, a primary object of the present invention 3 ¦to provide a wheelchair which may be constructed oE a main frame and ~¦ a plurality of commonly sized au~iliary components adjustably 5 ¦attached to the main frame in order -to sui-t different sized users.
61 It is another object of -the present invention to provide a 71 wheelchair of the type stated in which a seat section can be adjust-81 ably attached to the main frarne in a variety of positions and a foot

9¦ support member can be adjustably attached to the main frame in a 0¦ number of positions/ and with at least front or rea~r wheels capable 11¦ of belng adjustably attached to the main frame in a variety of 1~¦ positions.
3¦ It is a further object of the present invention to provide a 14¦ wheelchair of the type stated having rear wheels which are capable 15¦ of being shifted longitudinallyahd vertically in order to change 16¦ the wheel base of the wheelchair and vertically in order to change 1~ the angle o~ attack of the wheelchair.
18¦ It is an additional object of the present invention to provid 19~ a wheelchair of the type stated in which the front wh~els can be 20¦ adjustably positioned, and in which a front wheel mounting means is 21¦ capable of receiving different sized front wheels.
22¦ It is still another object of the present invention to pro-23¦ vide a wheelchair construction of the type stated which is uniquely 241 adapted for normal use and also for athletic activities, by mere 251 adjustment of the positions of the wheels.
26¦ It is still another object of the present invention to pro-271 vide a method of manufacturing a wheelchair from a limited number of 2~¦ common components such that the wheelchairs can be of differing 29¦ sizes in order to suit different sized users.

31 It is still a further object of the presen-t invention to _ 5 _ 1 provide a method of changing the wheel base and also changing the 2 center of gravity of a wheelchair in order to permit the same to be 3 used in normal transport activities and also for athletic activitîes 4 With the above and other objects in view, my invention reside 5 in the novel features of form, construction, arrangement and combin-6 a on ot parts presently described and pointed out in the claims.

~Z

1 SUMMARY or THE DISCLOSURE
2 A wheelchalr comprising a main frame, a seat structure, and 3 a foot support structure with the latter two components capable of being adjustably positioned on the main frame. In this way, a wheel 5 chair constructed from commonly sized components can be made in a 6 number of different sizes in order to suit differing sized users 7 and users with different forms oE disabilities or deformities.
8 The main frame generally comprises a plurality of longitudi-9 nally extending rigid members which are connected by a plurality of

10 transversely extending rigid members. A plurality of first upright

11 members are located on ~ rear portion of said frame, and a plu~a-~2 lity of second upright members are located on the front portion of ~3 said main frame The seat structure is capable of being attached to 14 and adjustably positioned on the main frame, as aforesaid. The 1~ seat structure is comprised of a seat frame having a plurality of 16 first posts capable of being fitted with respect to a separate one 17 of the first upright members and adjustably located thereon. A
18 seat pad is also carried by this frame.
19 One of the other main components forming part of the wheel-2P chair is the foot support structure which is also capable of being 21 attached to and acl~ustably positioned at a front portion of the main 22 frame. The foot support structure is comprised of a plurality of 23 second posts with each capable of being fitted with respect to a 24 separate one of the second upright members. A foot receiving member 25 is a].so carried by these second posts. In this way, several differ-26 ent sized wheelchairs can be constructed with commonly sized main 27 frames and foot support structures and seat structures.
28 The seat frame preferably has additional posts capable of 29 being fitted with respect to upper ends of the first upright tubular 30 members as well. In another embodiment of the invention, the uprigh :

1~ 7 1 members and the posts are capable oE being fltted with respect to 2 one another and adjustably telescopically arranged. More specifi-3 cally, the upright members are -tubular, and the posts are capable of being fitted within the open ends of the upright members.
In another embodiment of the invention, arm rests or side 6 frames~are capable of being ad~ustabl~ attached to the main frame.
7 In like manner, rear wheels are capable of being mounted with 8 respect to the main frame in a plurality of positions, and front 9 wheels are also capable of being mounted with respect to the main frame in a plurality of positions.
11 The present invention also provides an apparatus for select-

12 ively positioning the rear wheels of a wheelchair to selectively ~3 alter the center of gxavity thereof. This apparatus comprises a 14 pair of spaced apart plates which are mounted on the main frame. A
15 plurality of axle receiving locations are provided on each of the 16 spaced apart plates and are capable of receiving a rear wheel axle 17 in each of such~locations. A rear wheel axle is provided and is 18 capable of extending in the rear wheel axle locations on each of 19 said plates. Further, a quick release means is associated with the rear wheel axles to enable quick release and replacement of rear 21 wheels on these rear wheel axLes. Thus, the rear wheel axles can 22 be easily removed from one location and replaced in another axle 23 receiving location so that the reponse and center of gravity and 24 the wheel base on said frame can be easily and quickly altered. In 25 more detail, the axle receiving locations comprises a plurality of 26 pairs of spaced apart openings in each of the spaced plates to re-27 ceive the rear wheel axles. These plates are located on opposite 28 sides of the main frame. Fur-ther, a retaining member may be 29 associated with each of the plates. Each retaining member is also provided with a plurality of openings which are aligned with the ~8-~ t7 1 ¦ openings on the plates with which the retaining members are associ-2 ¦ ated.
3 ¦ In another embodiment of the invention, the ~uick release 4 means are preferably located on each rear wheel axle. The quick ~ I release means may comprise at least one retaining pin extending out-6 ¦ wardly from the axle and capable of being retracted therein -to per-7 ¦ mit removal of the wheel on -khe axle. A manually actuable means, ~ ¦ such as a shiftable rod on each shaft, causes said retaining pln to 9 ¦ be retracted upon actuation thereof.
10 ¦ As indic~ted previously, the front wheels on each of the 11 ¦ wheelchairs can also be adjustably positioned. Particularly, the 12 ¦ front wheels can be selectively positioned to alter the angle of

13 ¦ attack of the wheelchair relative to a ~round plane. As used herein¦

14 the term "ground plane" refers to a ground surface or other support-

15 ¦ ing surface upon which the wheelchair would be used and is generally

16 ¦ a horizontal plane. Further, the position of the front wheels can

17 ¦ be altered relative to the rear wheels in order to change the wheel

18 ¦ base. Thus, for example, the rear wheels can be shlfted closer to

19 ¦ or further from the front wheels and/or the front wheels can be

20 ¦ shifted closer to or further from the rear wheels. In addition to

21 ¦ the above, the front wheels and the rear wheels can be shifted si-

22 ¦ multaneously in the same direction to affect the positions of the

23 ¦ front and rear wheels relative to the main frame in order to vary

24 ¦ thè riding characteristics of the wheelchair.
The apparatus for selectively positioning the front wheels ~6 comprises a pair of wheel post housings on the main frame means. A
2~ post extends outwardly from each of these wheel post housings. A
2~ separate bracket is carried by each of the posts and is rotatable 29 about a generally verticle axis relative -to the associated wheel post housing. Each of the brackets has a pair of spaced apart 31 plates with a plurality of aligned apertures in said spaced apart 32 plates. A separate wheel assembly is also provided for each _9~

-L.l~b~1; 7 1 ¦bracket, and each wheel assembly is comprised of a wheel and a front 2 ¦wheel axle capable of being disposed in any of the plurality of 3 ¦aligned apertures. In this way, it is possible to adjust the plane 4 ¦of the frame, and hence, the angle of attack of the wheelchair 5 ¦relative to the ground plane.
8 ln another emoodiment of the invention, these front wheel 10~
1~ 1 G ¦

_9~_ 1. 1~ ,il'7 1 ¦brackets are sized so that different sized wheels can be removably 2 ¦mounted with respect to the brackets. Further, the wheel posts are 3 ¦generally vertically located, and said posts extend downwardly and 4 ¦outwardly from the associated wheel post housing.
5 ¦ The rear wheels are normally adapted for enyagement with the 6 ¦ground or other supporting surface and are capable of being opera-~ ¦tive]y engaged by a user for propelling the wheelchair. In like~man 81 ner, the front wheels are normally adapted for engagement with the 91 ground or other supporting surface. The front wheels typically have 10¦ a diametral size which is substantially less than the rear wheels.
11¦ In one embodiment of the lnvention, a foot rest member or foot sup-~21 port member may be provided on the frame means and extend forwardly ~31 therefrom as aforesaid. A pair of rollers may be provided on the 14¦ oot rest member and are normally spaced above the ground or other 15¦ supporting surface when the wheelchair is used for normal transpo1-t.
16¦ Howe~er, these rollers enable the wheelchair to be tipped forwardly 17¦ by the user thereof so that the rear wheels are temporarily raised 18¦ from the ground or other supporting surface, and the rollers are 19 ¦thereupon lowered into engagement with the ground or other support-20¦ ing surface. This may be a temporary condition which may exist in 21¦ a-thletic activities or the like. Moreover, in the event that the 22 ¦user of the wheelchair becomes overzealous and attempts to tip the 231 wheelchair, as for example, in an athletic activity, the rollers 24 ¦will prevent the entire wheelchair from tipping over.
251 In still a further embodiment of the invention, it is also 26¦ possible to provide an outwardly extending frame on the rear portion 271 of the wheelchair, if desired. This latter frame may also be pro-281 vided with rollers on the lower portion thereof. Thus, these rol-29¦ lers on the rearwardly extending frame would also engage the ground 301 or other supporting surface when the front wheels were temporarily ~ -10-(.17 l ¦ tipped above the ground or other supporting surface.
¦ The rollers which are typically used on a wheelchair, as 3 ¦ afoxesaid, have a diametral size which is substantially less than ¦ the fron-t wheels. Further, the front wheels and rollers are mounted ~ ¦ so that they are capable of rotation in the sam~ direction as th~
6 ¦ rear wheels and are also capable of rotation about a vertical axis.
7 ¦ The rollers in this case may adopt the form of casters.
8 ¦ It is also possible to cant (often referred to as "camber") 9 ¦ the rear wheels so that the lower portions are disposed outwardly lO ¦ with respect to the main rame, and the upper portions are disposed ll ¦ inwardly toward the frame. This type of canting or cambering of the 12 ¦ rear wheels also provides increased stability, particularly when 13 ¦ the wheelchair is used in athletic activities. In addition to the 1~ ¦ canbering, the wheels can be toed in or out/ as may be decreed.
15 ¦ This invention possesses many other advantages and has other 16 ¦ purposes which may be made more clearly apparent from a consideratio 17 ¦ of the forms in which it may be embodied. These forms are shown in 18 ¦the drawings forming and accompnaying part of the present specifi-19 ¦cation. They will now be described in detail for the purposes of 20 ¦ illustrating the general principles of the invention, but it is to 21 ¦be understood that such detailed descriptions are not to be taken 22 in a limiting sense.

1 ¦ BRIEF DESCRIPTION OF THE DRA~INGS
~¦ Having this described the invention in general terms, 3 ¦ reference will now be made to the accompanying drawings (four 41 sheets) in which:
51 FIGURE 1 is a side elevational view of a wheelchair ~¦ constructed in accordance with and embodying the present inven-71 tion;
81 FIGURE 2 is a front elevational view of the wheelchair of 9¦ Figure 1;
10¦ FIGURE 3 is a fragmentary front elevational view showing 11 the front wheels of the wheelchair in an alternate position;
12 FIGURE 4 is a fragmentary vertical sectional view taken 1~ along line ~-4 of Figure l;
14 FIGURE 5 is a perspective view of a rear wheel mounting bracket forming part of the wheelchair of the present invention;
1~ FIGURE 6 is a top plan view, partially broken away and 17 in section, and showing the means for attaching the mounting 18 bracket of Figure 5 to the main frame of the wheelchair;
19 FIGURE 7 is a side elevational view, partially broken away and in section, and showing a quick release means for 2~ removably locking a rear wheel to the wheelchair and taken along 22 line 7-7 of Figure l;
23 FIGURE 8 is a vertical sectional view of one form of ~4 quick release means;
FIGURE 9 is a side elevational view, partially broken 26 away, and showing the shifting of an arm assembly forming part of 27 the wheelchair of the present invention;
28 FIGURE 10 is a perspective view of a portion of a seat 29 structure Eorming part of the wheelchair of the present invention;
33l and 1 ¦ FIGURE ll is a side elevational view, partially broken 2 ¦ away and in section, and showing a portion of the seat pad forminy 5 ~ p rt of the seat sturcture of the invention.

lZ~
l3 2' -!
-13- ~

~ ~ p~

2 Referring now in more detai.l and by reference characters 3 to the drawings which illustrate practical embodiments of the present invention, A designates a wheelchair having a main frame ~ 10. The main frame 10 is more fully illustrated in Figures 1 and 6 2 and comprises a pair of longitudinally extending lower bars 12 and a pair of upwardly spaced longitudinally extending upper bars ~ 14. At the rearward end, the upper and lower bars 14 and 12 are 9 connected by a pair of transversely spaced apart vertically extending bars or rigid members 16. At their forward ends, the 11 upper and lower sets o~ bars 12 and 14 are connec-ted by somewhat 12 upright rigid members or bars 18, in the manner as more fully 13 illustrated in Figures 1 and 2. In like manner, intermediate 14 the rear upright rigid members or bars 16 and the front bars 18 are a pair of intermediate upright bars 20 which connect each 16 of the opposite sides of the upper and lower bars 12 and 14.
17 The intermediate bars 20 are spaced somewhat closer to 18 the rear upright bars 16. In this respect, the front bars 18 19 are referred to as being upright, even though they are not truly, vertically disposed, inasmuch as they do have a vertical compo-2~ nent and do extend between the lower and upper bars 12 and 14.
22 Extending between the lower bars 12 i5 a txansversely 23 extending connecting bar 22. In like manner, extending between 24 the rear upright bars 16 is a transversely connecting bar 24.
Each of the aforesaid bars are essentially welded with 27 respect to one another in order to form -the overall main frame 10, 2 in the manner as illustrated. Thus, these main bars may be formed 28 of various metals, such as steel, stainless steel, alumi~num, or 29 the like. In one of the more preferred embodiments of the inven-tion, each of the components of the main frame is preferably '7 1¦ formed for aluminum or titanium in order to provide the light 21 weight to the wheelchair, and also to provide the necessary 31 rigidity. In addition, the use of these metals also permits the 41 wheelchairs to withstand a substantial amount of physical abuse, 51 as for example, the kind encountered in sports`activities 6 Each of the aforesaid bars is also rectangular in con-7 struction and tubular. However, if desired, the bars could be 8 formed of a solid metal. ~oreover, the rectangular shape has been 9 found to be not only aesthetically desirable, but highly effective to provide the necessary degree of rigidity.
~1 This main frame 10 can be used in order to construct a 12 variety of different sized wheelchairsby merely adjustably posi-13 tioning the seat structure and the foot support structure as here-1~ inafter described in more detail. Moreover, this same main frame may be used in the construction of wheelchairs which function for 16 normal transport and which can also be used in athletic activities.
17 Otherwise, the same main frame can be used in the manufacture of 18 a wheelchair primaril~ designed for athletic activities or other-19 wise, a wheelchair normally and primarily designed for normal transport.
2~ Provided for attachment to the lower ends of the front 22 uprights 18 is a foot support structure 26, and which foot support 23 structure is more fully illustrated in Figures 1 and 2 of the 24 drawinqs. The foot support structure 26 is comprised of a generally horizontally disposed foot suppor-t member 28 which integrally 26 merges through arcuately shaped bends 29 into a pair of upright 2~ posts 30. By further reference to Figure 2, it can be observed 28 that the posts30 are aligned with the open lower ends of the 29 uprights 18. Moreover, the posts 30 are capable of extending into the tubular uprights 18 so as -to adjust the overall distance ~ r '7 1 be-tween the main frame 10 and the horizontal foot support member 28.
2 In addltion, the posts are secured within the tubular uprights 18 3 in the desired positions by means of set screws or similar forms 4 o~ fasteners 31. It can be observed, that by adjusting the position of the posts 30 within the lower ends of -~he uprights 18, 6 that it is possible to adjust the overall distance of the foot ` 7 support member 28 to a seat (hereinafter described) and also to 8 adjust the overall effective horizontal distance o~ the foot 9 support member from the main frame.
The foot support member is also preferably formed of 11 light weight metals, such as aluminum, or the like. Moreover, 12 for ease of construction, simplicity, and lo~ cost, the foot 13 support member 26 can be formed almost as an integral structure 14 with the tubular member being bent for insertion-into the posts.
Mounted on foot support member 28 is a front roller 16 assembly 32, and which is comprised of a bracket 33 rigidly 17 mounted on -the horizontal rod 28. Carried by the bracket is a 18 pin 34 which, turn~ carries a pair of rollers 36. By reference to 19 Figures 1 and 2, it can be observed tha-t the rollers 36 are raised above the ground or other supporting surface when the rear wheels 2~ and the front wheels are located in contact with the ground or 22 other supporting surface. However, it can be observed that during 23 any activity if the rear wheels should be temporarily elevated 2~ from the ground in an attempt to tip the chair by the user, the front rollers 36 will contact the ground to prevent the chair 26 from tipping over. Again, means could be provided for adjusting 27 the relative height of the rollers 36 such that they could provide 28 the desired amount of clearance, and yet also prevent an inadver-29 tent complete tipping over the wheelchair, which could result in injury to the user.

ti~..17 1 It should be understood that a similar frame could be 2 mounted on a rear portion of the main frame 10 so as to mount 3 rear rollers similar to the front roller assembly 32. In this 4 way, if -the wheelchair were tipped rearwardly, such rear rollers would also prevent the wheelchair from -tipping over in the rear-6 ward directi.on.
7 The illustrated and described wheelchair A also comprises 8 a seat structure 38 which is more fully illustrated in Figures 1 9 2, 10 and 11. The seat structure 38 generally comprises a buttocks and leg supporting seat section 40 and a back supporting section 11 42. The back supporting section 42 generally comprises a pair of 12 tubular posts 44 which are generally circular in shape and are 13 adapted to extend into the opened upper ends of the rear uprights 14 16. Tubular posts 44 also extend into pockets 46 formed along the opposite transverse ends of a backrest pad 48. Moreover, 16 the pockets 46 merge into shoulders 50 at their lower ends.
17 Mounted on the posts 44 are collars 52 which are adjustably 18 positioned thereon by means of set screws 54. In this ~ay, the 19 collars 52 will control the distance that the posts 44 extend into the pockets 46. Moreover, the collars 42 can abut the upper ends 2~ of the upri~hts :L6 when the back support 42 shifted to its lower-22 most position. Thus, the collars 52 also provide a means to 23 adjust the overall hei~ht of the back support pad 48.
24 The back support pad 48 may also be provided with a securement strap 56 which is adapted to extend around 26 crossbar 24. Purther, the securement strap 56 would be provided 27 with an attachment means 60 which, in this case, adopts the form 28 of elcro releasably ettachable st~lp~.

~ G7 1 The back support pad 48 is pre-Eerably comprised of an outer 2 cover, such as a cloth material, and an inner pad (not shown), and 3 which is formed of a resillent material such as a styrafoam or 4 polyurethane foam. In this way, the outer cover of the back seat support 48 could be changed if desired.
6 The frame also includes a horizontal frame section 62 ~~
7 or so-called seat support section comprised of a pair of horizon-tally disposed longitudinally extending and transversely spaced 9 apart rods 64 which are secured at their rearward ends to the uprlghts 16 thereby forming a single seat frame. At their forward 11 ends, the rods 64 integrally merge into generally downwardly struck 12 posts 66 which are adapted to extend into the opened upper ends of 13 each of -the front forward uprights 18, in the manner as best seen ~4 in Figures 1 and 2 of the drawings. Moreover, while not absolutely necessary, in some cases, it may be desirable to secure the posts 16 66 in their telescoped position within the uprights 18 by means of 17 suitable fasteners, such as set screws, or the like.
18 The longitud:inally extending rods 64 also telescopically merge 19 into forwardly extending frame members 68 located parallel to the above mentioned frame members 14, as more fully illustrated in 2] Figures 1, 2, 10 and 11. The supporting seat section 40 is providec 22 with an outer cover 70 which is provided with sewn pockets 72 in 23 order to receive the rods 68 along with the longitu~inally extend~
24 ing rods 64. The pockets 72 are designed so that the rods can be removed therefrom in order to permit the mounting of a new outer 26 cover 70. Suitably enclosed within the cover 70 is a pad 74 27 similar to the pad used in the back section 48. Thus, this pad can 28 be formed of a foam type material, such as a urethane foam, or the 29 like. The cover 70 is provided with a front opening and a releas-ab fl~p 76 ln ~ r to ~ !

'7 1¦ permit access to the pad 74. Moreover, the flap 76 is securable to the underside of the cover 70 by means of a suitable securement 3 means, such as a Velcro attachment, or the like.
4 This construction is highly effective in that lt enables ~ the pad 74 to be easily interchangeable. In many cases, the users 6 of wheelchairs are incontinent or o-therwise have diffïculty 7 controlling body discharge, such as urine. As a result, the pad 8 74, and for that matter, the seat cover 70 may become soiled and ~ require replacement. This construction enables very easy removal of one soiled pad and insertion of a new seat pad 74. In like 11 manner, this construction also enables easy and convenient 12 exchange of one supporting seat structure for another.
13 The wheelchair can be provided with an arm rest structure 14 80 or so-called side rail structure or arm support structure.
One embodiment of the arm rest structure which may be used in the 16 illustrated and described wheelchalr is more fully illustrated in 17 Figure 1 of the drawings. The arm rest or side rail structure 80 18 is generally comprised of a palr of vertically disposed tubular 19 retainer sleeves 82 which are mounted on the rear portion of the wheelchair as more fully illustrated in Figure 1.
2~ The supporting sleeves 82 are provided at their lower 22 ends with forwardly struck brackets 84 for securement to the frame 23 of the wheelchair by means of conventional fasteners, as for 24 example, by screws 86. In this way, the -tubular supporting sleeves32 may be removably mounted on the wheelchair when it is 26 desired to use an arm supporting structure 80.
2't Secured to the forward ends of `each of the opposite 2~ horizontally disposed rods 14 are platesJ88 which carry at their 29 forward ends, upwardly disposed tubu/a ~ sleeves 90. In like 31 manner, the tubular sleeves 92 also cooperate with the sleeves 90 -19- ~

IL1~ 7 1 ¦ and are located-to receive rods 44, which are, in turn, remova~ly 21 disposed within the sleeves 82. The sleeves 92 are horizontally 31 disposed, and the sleeves 90 and 92 in the respect:lve pairs, 41 removably attach rods 94 by means of set screws 95 and r*vets 98, 51 respectively. In this way, the rod 94 along with cooperating 61 sleeves 90 and 92 and the sleeve 82 each form a side rail on 71 opposite sides of the wheelchair A~
81 The arm supporting structures 80 are also shiftable out ~¦ of the way in order to permit entry into and removal of a person lO¦ from a wheelchair. For this purpose, the plate 88 may be 11 removably secured to longitudinally extending barsl4 by removable ~2 locking pins 100. These locking pins 100 are conventional in 3 their construction. Typically, they are provided with a manually 14 actuable member, such as a push-button, in order to permit release of the locking pin. Thus, when the locking pin 100 has been 16 removed, the plate 88 is disenga~ed from the rod 14 thereby 17 permitting the entire arm portion, including the sleeves 90 and 18 92 and the rod 94, to be shifted in a lateral direction about a ver-19 tical axis extend:ing through the sleeve 82. In like mannerj the a~ m supporting structl~res can be returned to their position on the 2~ sides of the wheelchair by merely locking theplates 88 into the bar s 22 14 with the locking pins 100.
23 On the forward ends of the wheelchair A, on each of the ~4 opposite sides thereof, are front wheel assemblies 102 and which are more fully illustrated in Figures 1-3 of the`drawings. Each 26 front wheel assembly 102 generally comprises a mo~nting hub 104 ~7 which is rigidly secured to an inverted U-shape~bracket 106 as 28 best seen in Figure 4. In this case, ~he~bracket 106 is adapted 29 to be disposed over either of the longitudinally extending bars 12.

31 Moreover, the mounting hub 104 may be secured in a selected 32~ -20-1 position along the longitudinal bar 12 by means of a bolt 108 which 2 extends through the bracket 106 and into the mounting hub 1~4.
3 Disposed wi~hin and e~tending downwardly from the mountlng hub 10~
4 is a rod 110 which is secured within the hub 104 by means of a nut 112 at a threaded upper end of the rod 110. The rod 110 is, in 6 turn, secured at its lower end to a whee] supporting bracket 114 7 which is generally of an inverted U-shape, as also best seen in 8 Figures 2-~ of the drawings. The wheel mounting bracket 114 is 9 provided with a first pair of lower axle recelving apertures and an upwardly located second pair of axle receiving apertures 116.
11 In this case, each of the apertures in the respective pairs are 12 located on opposite sides of the wheel mounting bracket 114. A
13 wheel assembly 118 is comprised of a wheel axle 120 and a front 1~ wheel 122 is mounted in one of the pairs of apertures in the lower pairs of apertures 116, as shown on each of tihe brackets.
16 The second pair of apertures 116 which are located upwardly 17 from the lower pair are adapted to receive axles and wheels of 18 larger diameter. In this way, the front wheels can either be 19 mounted in the upper apertures such that a forward tilt is provided to the wheelchair, otherwise, larger wheels could be so mounted.
21 It should be understood that additional pairs of apertures could be 22 provided in each of the wheel mounting brackets 114 as may be 23 desired in order to further adjustably position the wheels, or to 2~ otherwise, provide for different diameter wheels.
By means of the abo~e construction, it can be observed that 26 the front wheels can be shifted clcser to or further from the rear 27 wheels in order to change the overall wheel base of the wheelchair.
28 Further, the shifting of the front whee~s relative to the rear wheel s 2g Imay also affect the angle of attack of the wheelchair as hereinafte~
30 Idescribed in more detail. Thus, for example, if the rear wheels are 31 I!changed in vertical position, the position of -the front wheels rela 32l tive to the rear wheels will affect ~he angle of a-ttack.

1~ 7 1 sy further reference -to Flgures 2 and 3 of the drawings, it 2 ¦ can be observed that the front wheels can be reversed so as to be 3 ¦ located either inwardly or outwardly of the main frame 10. Figure 4 ¦ 2 illustrates the front wheels or so-called "casters" mounted ex-5 ¦ teriorly on the opposite longitudinal sides of the frame 10. By 6 ¦ merely loosening the bolt 108 and removing the bracket 106, it is 7 ¦ possible to rotate each of -the front wheel assemblies and mount ~¦ them on the interior of the lower rails 12 as illustrated in Figure 9~ 3 of the drawings. This latter arrangement is preferred when the 10¦ wheelchair is to be used in athletic activities in order to provide 1¦ greater clearance, as for example, in bounciny a basketball moving .12¦ a tennis racket, or the like. In this way, the front wheels will 3¦ not interfere with any moving object or a moving arm of the user 1~¦ of the wheelchair.
15¦ The wheelchair A of the present invention is also provided 16¦ with a pair of rear wheels 130 and which are retained on the wheel-17¦ chair on the main frame 10 by means of rear wheel mounting assem-18¦ blies 132 which are more fully illustrated in Figures 1 and 5-7 of 19¦ the drawings. In this case, the rear wheels each comprise a center 20¦ hub 134 which is capable of receiving a rear wheel axle 136 as 21¦ hereinafter described in more detail. The center hub is connected 22¦ to a relatively rigid rim 138 by means of a plurality of spokes 140.
23 ¦Suitably mounted on the rim 138 is a tire, which is preferably a 2~ ¦rubber tire 142. In a conventional mannerr it is preferable to

25 ¦ have the tire 1~2 removably mounted for purposes of replacement.

26 ¦ Also suitably mounted on each of the wheels 130 is a hand engagable

27 ¦circumferentially extending rim 144 which is adapted to be engaged

28 ¦ by the hands of the user for causing roation of the wheels about

29 ¦ their central axis and thereby causing propelling movement of the

30 ¦ wheelchair.

31¦ The rear wheel mounting means 132 preferably comprises a 321 mounting bracket 1~6 which is, in turn, mounted to -the main frame 11tlfti~( 7 1 10 of the wheelchair. Each of the brackets 146 are mounted to the 2 upstanding bar 16 and the intermediate upstanding bar ~0 in the 3 manner as illustrated in Figure 1 of the drawings. Each of the 4 brackets 146 are provided with a face plate 148 and a spaced-apart mating pla-te 150 connected to the plate 14~ by means of a pair of 6 rearwardly ex-tending arms 152. Moreover, the plate 148 is secured 7 -to the upstanding bars 16 and 20 by means of sheet metal screws, 8~ bolts or similar fasteners 154. For this purpose, the plate 148 is 9¦ provided with a plurality of bolt recelving apertures 156 in the 0¦ manner as illustrated in Figure 5 of -the drawings. Further, it can 1~¦ be observed that the inwardly located mating plate 150 has a smalle 12¦ si~e than the plate 148 so as to be snusly disposed between the 3¦ two upstanding bars :L6 and 20.
4¦ Each of the plates 14~ and 150 are provided with a pluralit~
15¦ of aligned apertures 158 for receiving a rear wheel axle 136. Thes 16¦ apertures 158 and 160 define rear wheel axle receiving locations 17¦ such that the rear wheel axles 136 can be located in any of the 1~¦ sets of apertures 158 and 160.
19¦ By reference to Figure 7 of the drawinys, it can be 20~ observed that the mounting bracket 146 is no-t mounted in a truly 21 ¦vertical position. Rather, the bracket 146 is canted somewhat such 22 ¦that the rear wheel axle 136 is also located at an angular relation 23 ¦ship with respect to a true horizontal. In this way, the rear 2~ ¦wheels 130 are canted somewhat in the manner as illustrated in 25 ¦Figure 2 of the drawings and as hereinafter described in more de-26 tail. The mounting brackets 146 may be mounted to the main frame 27 ¦by using one or more shims 162 in the manner as illustrated in 28 ¦Figure 7. In this way, the mounting bracket 146 is angulated away 29 ¦from -the true vertical position, and hence, the axle 136 is located 30 Iso tha-t the rear wheels are canted with the upper ends of the wheel 31 ¦being located inwardly and the lower ends of the wheels being struc ~2 ¦outwardly. It has been found in connection with the prasent 1~ 7 1 ¦ invention -that it is desirable to actually can-t the wheels in this 2 ¦ Eashion in order to provide greater stability to the wheelchair r 3 ¦ particularly when the latter is used in sports activities such as ¦racing events, and the like. The rear wheels may be cambered at an 5 ¦angle of about o to about 10 per wheel from a truly vertical position, and preferably, from an angle of about 3 to about S per ~ ¦ wheel in order to achieve the most desirable results.
8 ¦ Alon~ with the cambering of the rear wheels, these wheels can 9 ¦also be toed inwardly or outwardly by using shims (not shownl on the 10 ¦mounting brackets 146. Typically, it is desirable to toe -the rear 11 ¦wheels outwardly when the rear wheels are cambered. Preferably, the 12 ¦rear wheels should be towed out at a ratio of one-third of the 1~ ¦camber. Thus, for example, for every degree of camber, there should 14 ¦be a toe-out of about one-third degree.
15 ¦ The rear wheel axles 136 actually form part of a quick 16 release lock mechanism 164 which is more fully illustrated in lq Figures 7 and 8 of the drawings. In this case, -the quick release 1~ lock mechanism includes a pin 166 which is concentrically located ~9 within a bore in the axle 136 such that the axle 136 is effectively an outer sleeve for the release pin 166. In addition, a washer or 21 outer sleeve 168 is~.disposed upon the axle 136 for limiting the 22 axial movement thereof when in position to hold a rear wheel therPon 2~ Further, a locking sleeve 170 having a knurled outer surface is also 2~ threadedly disposed on the threaded left hand end 172 of the axle 136. Thus, by positioning the locking sleeve 170, it is possible to 26 provide for the proper location of the abuttment sleeve 168. At its 27 left hand end, the axle 1.36 is provided with a handle 174, and which 28 receives an outwardly extending end 176 of the release pin 166. Thi 29 outwardly extending end 176 functions as a release button which is manually actuable to axially displace the pin 166 to thereby release 31 a pair of detent balls 178 at the right-hand end of the axle 136.

32 Further, the release pin 166 is provided with a plurality of ~rooves -2~

.~.18~2~J~7 ¦ 182 such that when p~lshed inwardly, the grooves 182 become aligned ¦ with the balls 178 permi-tting them to fall inwardly. However, when 3 ¦ the release pin 166 is biased to the left by means of a compression 4 ¦ spring 184, the balls are displaced by a shoulder 186 thereby biasin~
5 ¦ the balls 178 ou-twardly. In this way, the balls function as locking 8 ele ents.

ti;~ 7 1 Thus, when it is desired to mount a rear wheel in any of the 2 rear whee]. locations, the pin 166 can be pushed inwardly in through 3 the axle 136 thereby permi-tting the locking elements 178 to fall 4 radially inwardly toward the center of the axle. This will permit t.he axle to be removed from any of the aligned apertures 158 and 6 160. Moreover, the axle can -then be removed from the hub 134 of 7 the rear wheels. In like manner, when it is desired to mount the 8 rear wheel on the wheelchair, the release pin 166 is pushed in-9 wardly by manually engaging the outer end 176. Again, the locking 1~ elements 178 will be permitted to fall radially inwardly permitting 11 the hub 134 to be mounted on the axle 136 and also permitting the 12 axle to be inserted through the ali.gned apertures 158 and 160.
13 Thus, when the outer end 176 is released and the release pin 166 is 14 biased to the right, by means of the compression spring 184, the locking elements 178 will be hiased outwardly thereby retentively 1~ locking the rear wheel on to the wheelchair.
17 It can be observed by means of the above construction, that 18 it is possi.ble to selectively position the rear wheels on the wheel- .
19 chair frame. By positioning -the rear wheels so that they are located in the lower and rearwardmost corher of the brackets 146, 21 ¦ the wheelchair wi:ll assume a more standard riding posltion in the 22 ¦ same manner as conventional wheelchairs. Thus, the wheelchair will 23 ¦ function for normal day to day activity. By positioning the axle 24 ¦ in the upper and forwardmost apertures 158 and 160 of the bracket 25 ¦ 1~6, the rear portion of the wheelchair will be effectively shiEted 26 ¦ upwardly thereby raising the center of gravity. However, this is 27 ¦desirable in some situations. Thus, the center of gravity of the 28 ¦wheelchair can be easily altered. In addition, by shifting the 29 Irear wheel axles either rearwardly or forwardly in any of the 301 selected axle receiving locations, it is also possible to effectivel Y
31l change the overall wheelbase of the wheelchair in order to obtain 32 Il the desired riding characteristics.

.~ -25-ll~ti;~
1 Thus, there has been i]lustrated and described a unique and 2 novel wheelchalr which can be constructed in several differen-t 3 sizes from s-tandard sized co~.~ponent sets and on which is capable 4 of functioning for conventional movement as well as for athletic activities, and which therefore fulfills all of the objects and 6 advantages sought therefor. It should be understood that many 7 changes, modiEications, variations, and other uses and applications 8 will become apparent to those skilled in the after after consider-9 ing this specification and the accompanying drawings. Therefore, any and all such changes, modifications, variations, and other 11 uses and app].i.cations which do not depart from the spirit and 12 scope of the invetnion are deemed to be covered by the invention 13 which is limited only by the following claims.

,

Claims (2)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

A wheelchair capable of being used for sports activities and also for normal transport, said wheelchair comprising:
a) a frame means, b) a seat mounted on said frame means for supporting an individual using such wheelchair, c) a pair of driving wheel supporting brackets with each being mounted on an opposite side of said frame means and having a plurality of spaced apart axle receiving openings with each opening capable of receiving a rear wheel axle, d) a separate axle for removable disposition in each of the openings of each said supporting brackets and each axle being adapted to carry a separate driving wheel and which driving wheels are normally in engagement with the ground or other supporting surface, e) at least one additional wheel mounted on said frame means and normally being in engagement with the ground or other supporting surface, and f) a separate quick release means associated with each of said wheel axles to enable quick release and replacement of the driving wheels on said wheel axles, each of said quick release means comprising a manually actuatable element which automatically releases the axle from the opening when actuated and which permits re-insertion into the same or other openings by pushing the axle into said same or other opening where it becomes locked therein, such that each of said axles can be easily removed from an opening in a bracket and replaced in another axle receiving opening in said bracket so that the response and center gravity and wheel base on said frame can be easily and quickly altered.

The wheelchair of Claim 1 wherein a foot support member is on said frame means and extends forwardly therefrom.

The wheelchair of Claim 1 wherein at least a pair of said additional wheels are mounted on said frame means and have a diametral size smaller than said driving wheels.

The apparatus of Claim 1 further characterized in that one of said openings in each bracket is horizontally spaced from another of said openings in the same frame with each sized to receive said wheel axles.

The apparatus of Claim 1 further characterized in that another one of said openings in each bracket is vertically spaced from said first named opening in that bracket and sized to receive a wheel axle.

The apparatus of Claim 1 further characterized in that said manually actuatable elements are pushable pins which release and permit removal of said axles when pushed.

The apparatus of Claim 1 further characterized in that said axles are rear wheel axles and said quick release means are located on said rear wheel axles.

The apparatus of Claim 6 further characterized in that each of said quick release means comprises at least one retaining element extending outwardly from said axle and capable of being retracted therein to permit removal of a wheel on said axle, and said manually actuatable element of said quick release means causes said retaining element to be retracted upon actuation of said manually actuatable element.

The wheelchair of Claim 1 further characterized in that means is provided on each of the brackets for attachment to a frame of said wheelchair such that the brackets can be attached to the frame means in a desired location.

The wheelchair of Claim 8 further characterized in that each of said brackets can be attached to the frame of the wheelchair so as to achieve a desired camber for the driving wheels.

The wheelchair of Claim 1 further characterized in that a matrix of at least four by four of said aligned spaced apart openings are on each of said brackets to receive said axles.

The wheelchair of Claim 1 further characterized in that said manually actuatable element comprises a pushable pin extending axially through each of said axles, and locking means extending outwardly of said axle to hold same at an opening in a bracket and actuatable by said pin when pushed to cause said locking means to be retracted, such that only manual pushing of said element is sufficient to enable release and ultimate removal or re-insertion of an axle.

The wheelchair of Claim 12 further characterized in that said locking means comprises at least one retaining sphere extending outwardly from an aperture in said axle and capable of being retracted therein to permit removal of a wheel on said axle when said manually actuatable pin is pushed inwardly.

The wheelchair of Claim 13 further characterized in that means is provided to adjust the position of the axle and the amount of extension of the axle through the bracket.

The wheelchair of Claim 14 further characterized in that the means to adjust comprises a threaded sleeve for threaded adjustment.

The wheelchair of Claim 2 wherein a pair of rollers are on said foot rest member and normally being spaced above the ground or other supporting surface when said wheelchair is used for normal transport, said wheelchair capable of being tipped by the user thereof so that said driving wheels are temporarily raised from and said rollers are lowered into engagement with the ground or other supporting surface.

The wheelchair of Claim 1 further characterized in that said seat is located in a normal sitting location for supporting the user when said driving wheels and additional wheels are in contact with the ground or other supporting surface.

The wheelchair of Claim 16 further characterized in that said rollers have a diametral size substantially less than said additional wheels.

The wheelchair of Claim 18 further characterized in that said driving wheels are rear wheels and said additional wheels are front wheels and said front and rear wheels are mounted so that they are all located for rotation in the same direction and said rear wheels are not capable of rotation about a vertical axis, but that such rollers are capable of being rotated about a vertical axis.

The wheelchair of Claim 1 further characterized in that hand rims are mounted on said driving wheels for engagement by a user to propel the wheelchair.

The wheelchair of Claim 1 wherein the additional wheel comprises a front wheel and a pair of said front wheels are provided and said wheelchair is provided with an apparatus for selectively positioning the front wheels of the wheelchair to selectively alter the angle of attack of the wheelchair relative to a ground plane, said apparatus comprising:
a) a pair of wheel post housings on said frame means, b) a post extending outwardly from each of said wheel post housings, c) a separate front wheel bracket carried by each of said posts and being rotatable about a generally vertical axis relative to the associated wheel post housing, and said bracket having a pair of spaced apart plates with a plurality of pairs of aligned apertures in said spaced apart plates, and d) a separate wheel assembly for each said front wheel bracket and each wheel assembly being comprised of a wheel and an axle capable of being disposed in any of the plurality of pairs of aligned apertures to thereby adjust the plane of the frame and hence the angle of attack of the wheelchair relative to a ground plane.

The apparatus of Claim 21 further characterized in that said front wheel brackets are sized so that different sized front wheels can be removably mounted with respect to each of said front wheel brackets.

The apparatus of Claim 21 further characterized in that said wheel post housing are generally vertically located, and said posts extend downwardly and outwardly from the associated wheel post housing.

The apparatus of Claim 23 further characterized in that said pair of aligned apertures are vertically located on said spaced apart plates.

The wheelchair of Claim 21 wherein it is capable of being used for sports activities and also for normal transport, said wheelchair comprising driving wheel mounting means for operatively mounting said driving wheels to said frame means in such manner that said driving wheels are canted with the lower portions disposed outwardly with respect to said frame means and the upper portions disposed near said frame, to thereby provide stability to said wheelchair.

A wheelchair comprising:
a) a main frame being comprised of:
1) a plurality of longitudinally extending rigid members, 2) a plurality of transversing extending rigid members rigidly secured to said longitudinally extending rigid members, 3) a plurality of first upright members on a rear portion of said main frame, and 4) a plurality of second upright members on a front portion of said main frame, b) a seat structure capable of being attached to and adjustably positioned on said main frame, said seat structure being comprised of:
1) a seat frame having a plurality of first posts, each capable of being fitted with respect to a separate one of said first upright members and adjustably located thereon, 2) a seat pad carried by said seat frame, and c) a foot support structure capable of being attached to and adjustably positioned at the front portion of said main frame, said foot support structure comprised of:

1) a plurality of second posts, each capable of being fitted with respect to a separate one of said second upright members and adjustably located thereon, and

2) a foot receiving member connected to said second posts whereby several different sized wheelchairs can be constructed with commonly sized main frames and foot support structures and seat structures.

The wheelchair of Claim 26 further characterized in that said seat frame has additional posts capable of being fitted with respect to upper ends of said first upright tubular members.

The wheelchair of Claim 26 further characterized in that said upright members and the posts capable of being fitted with respect thereto are adjustably telescopically arranged.

The wheelchair of Claim 28 further characterized in that said upright members are tubular and said posts are capable of being fitted into said upright members.

The wheelchair of Claim 26 further characterized in that arm rests are capable of being adjustably attached to said main frame.

The wheelchair of Claim 26 further characterized in that rear wheels are capable of being mounted with respect to said main frame in a plurality of positions.

The wheelchair of Claim 31 further characterized in that front wheels are capable of being mounted with respect to said main frame in a plurality of positions.

A method constructing a wheelchair having a main frame and a seat structure and a foot support structure, said method comprising:
a) inserting posts of a seat structure into the upper ends of a plurality of first upright members on a rear portion of said frame, b) positioning said posts so that a seat on said seat structure is at a desired location and securing said posts, c) inserting posts of a foot support structure into the lower ends of second upright members on a front portion of said frame, and d) positioning said posts of said foot support structure so that a foot support member thereof is at a desired location and securing said last named posts whereby several different sized wheelchairs can be constructed with commonly sized main frames and foot support structures and seat structures.

The method of Claim 33 further characterized in that said method comprises insertion of additional posts on said seat structures into upper ends of said first upright tubular members.

The method of Claim 34 further characterized in that said upright members and the posts capable of being fitted therein are adjustably telescopically arranged.

The method of Claim 35 further characterized in that said method comprises adjustably attaching arm rests to main frame.

The method of Claim 34 further characterized in that said method comprises mounting rear wheels with respect to said main frame in any one of a plurality of different positions.

The method of Claim 37 further characterized in that said method comprises mounting front wheels with respect to said main frame in any one of a plurality of different positions.