US3869146A

US3869146A - Occupant actuated means for propelling, stopping, directing, and curb hopping a wheelchair

Info

Publication number: US3869146A
Application number: US330865A
Authority: US
Inventors: Donald L Bulmer
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-02-08
Filing date: 1973-02-08
Publication date: 1975-03-04
Anticipated expiration: 1992-03-04

Abstract

Self-propulsion subassemblies are respectively secured to large wheel receiving shafts or bearing bolts of wheelchairs and wheelstretchers. An occupant utilizing his arm, shoulder and trunk strengths operates these self-propulsion subassemblies to propel, stop, turn and/or curb hop his or her wheelchair. The wheelchair, in then serving as an extension of his or her body, becomes much more effective. A wheelstretcher likewise becomes much more maneuverable in moving its occupant. These selfpropulsion subassemblies are installed as important accessories on otherwise essentially undisturbed wheelchairs or wheelstretchers. Their addition does not effect the initially designed structures or operations of the wheelchairs or wheelstretchers, but rather substantially improves them when self-propulsion is undertaken. The self-propulsion subassemblies include: radially extending rotatable stroke handles, also referred to as drive bars or drive levers, each one being located outside a large wheel and mountable on a large wheel shaft, also referred to as a bearing bolt, secured in turn to the frame of a wheelchair by using a lock nut and, as necessary, spacing washers; drive dog subassemblies mounted on the free ends of respective stroke handles, having an adjustable position head frame, selectively positioned on the stroke handle, forward and/or reverse driving dogs pivotally secured to the head frame and formed to grip a tire of a large wheel upon a propulsion stroke and to release its grip on the tire upon a return stroke; resilient retainers to selectively hold one or both of the forward and/or reverse driving dogs well clear of the tire; and hand gripping or manipulating drive handle units, each mounted on a respective head frame and having a sleeve rotatable about its own mounting pivot pin and mounted either firmly or spring biased into radial alignment with the stroke handle; overall motion limit subassemblies for the stroke handles respectively secured to each bearing bolt, preferably by brazing and having a circular plate or disc with circumferentially spaced holes; two sets of bolts and nuts for selective positioning and securement in these circumferentially spaced holes in the disc to then serve as stops in limiting the forward and reverse motions of the stroke handle; and a clip mounted with one set of the bolts and nuts to hold the stroke handle in this selected inactive position, when the wheelchair is carried in a car or when the wheelchair is being pushed by an attendant; braking materials adjustably positioned on each stroke handle to be moved transversely into contact with a large wheel or the hand rim of a large wheel, as the drive handle units are pushed transversely toward one another; and retractable and extendable additional length units of each stroke handle, optionally mounted so the extended stroke handles, also referred to as drive bars or drive levers, upon pivoting in contact with the ground, movably support the wheelchair and the occupant during his or her curb hopping maneuvers.

Description

llnlted States Patent [191 .ulmer [451 Mar. 4, 1975 OCCUPANT ACTUATED' MEANS FOR PROPELLlNG, STOPPING, DIRECTlNG, AND CURB HOPPING A WHEELCHAIR [76] Inventor: Donald L. Bulmer, 15404 63rd Ave., Bothell, Wash. 98011 22 Filed: Feb. 8, 1973 [21] Appl. No.: 330,865

[52] U.S. Cl 280/242 WC, 280/52 [51] Int. Cl. 362m 1/14, B62rn 29/02 [58] Field of Search... 280/242, 244, 296, 242 WC,

280/210, 211; 297/DIG. 4; 74/l4l.5, 577 M Primary Examiner-David Schonberg Assistant E.rmniner-Terrance L. Siemens Attorney, Agent, 0r.FirmRoy E. Mattern, Jr.

[57] ABSTRACT Self-propulsion subassemblies are respectively secured to large wheel receiving shafts or bearing bolts of wheelchairs and wheelstretchers. An occupant utilizing his arm, shoulder and trunk strengths operates these self-propulsion subassemblies to propel, stop, turn and/or curb hop his or her wheelchair. The wheelchair, in then serving as an extension of his or her body, becomes much more effective. A wheelstretcher likewise becomes much more maneuverable in moving its occupant. These self-propulsion subassemblies are installed as important accessories on 0th erwise essentially undisturbed wheelchairs or wheelstretchers. Their addition does not effect the initially designed structures or operations of the wheelchairs or wheelstretchers, but rather substantially improves them when self-propulsion is undertaken.

The self-propulsion subassemblies include: radially extending rotatable stroke handles, also referred to as drive bars or drive levers, each one being located outside a large wheel and mountable on a large wheel shaft, also referred to as a bearing bolt, secured in turn to the frame of a wheelchair by using a lock nut and, as necessary, spacing washers; drive dog subassemblies mounted on the free ends of respective stroke handles, having an adjustable position head frame, selectively positioned on the stroke handle, forward and/or reverse driving dogs pivotally secured to the head frame and formed to grip a tire of a large wheel upon a propulsion stroke and to release its grip on the tire upon a return stroke; resilient retainers to selectively hold one or both of the forward and/or reverse driving dogs well clear of the tire; and hand gripping or manipulating drive handle units, each mounted on a respective head frame and having a sleeve rotatable about its own mounting pivot pin and mounted either firmly or spring biased into radial alignment with the stroke handle; overall motion limit subassemblies for the stroke handles respectively secured to each bearing bolt, preferably by brazing and having a circular plate or disc with circumferentially spaced holes; two sets of bolts and nuts for selective positioning and securement in these circumferentially spaced holes in the disc to then serve as stops in limiting the forward and reverse motions of the stroke handle; and a clip mounted with one set of the bolts and nuts to hold the stroke handle in this selected inactive position, when the wheelchair is carried in a car or when the wheelchair is being pushed by an attendant; braking materials adjustably positioned on each stroke handle to be moved transversely into contact with a large wheel or the hand rim of a large wheel, as the drive handle units are pushed transversely toward one another; and retractable and extendable additional length units of each stroke handle, optionally mounted so the extended stroke handles, also referred to as drive bars or drive levers, upon pivoting in contact with the ground, movably support the wheelchair and the occupant during his or her curb hopping maneuvers.

6 Claims, 32 Drawing Figures PATE'NTED 3.869.146

saw 295 5 PATENTED W 41975 m 5 gr 5 FIG. 29

2 3 mm F OCCUPANT ACTUATED MEANS FOR PROPELLING, STOPPING, DIRECTING, AND CURB IIOPPING A WHEELCHAIR CROSS REFERENCE In an earlier U.S. Pat. No. 3,309,l l0, Donald L. Bulmer provided an occupant-propelled wheelchair with special driving mechanisms used by an occupant who could only apply a force in a direction opposite to the direction of the wheelchair travel.

BACKGROUND OF THE INVENTION In earlier patents such as Donald L. Bulmers U.S. Pat. Nos. 3,309,l James F. Petersons US. Pat. No. 3,189,368; Brian T. Goods U.S. Pat. No. 3,301,574; and Dewey O. Haynes U.S. Pat No. 3,623,748, mechanisms are provided, so an occupant may propel his or her wheelchair without either directly handling a large rolling wheel or handling a handrim which is a hand manipulated large propulsion ring which might be secured to the large rolling wheel. There remained a need, however, for a self contained adjustable subassembly, available in several selectable embodiments depending on the operational functions wanted, which would be installed quickly without altering the conventional wheelchairs such as the universal wheelchair, the traveler wheelchair, and others with different wheel arrangements, and be hand manipulated by the occupant to propel the wheelchair in any direction, stop, it, and, when necessary, raise it up over a curb or similar obstruction while they remain seated. Also, such a selfcontained adjustable subassembly would be installed on wheelstretchers and perhaps other equipment which could be self-propelled by an occupant.

SUMMARY OF THE INVENTION Occupants of wheelchairs are provided with selected embodiments of self-contained adjustable subassemblies securable at the large wheel shafts of many wheelchairs, such as universal and traveler wheelchairs, without otherwise altering the original wheelchair, to thereafter extend their ability to maneuver their wheelchairs. Also other wheeled carriers such as wheelstretchers may be equipped with these subassemblies to aid the occupant in self-propelling the wheeled carrier to extend his or her mobility range.

Depending on the selected embodiment of these selfpropulsion subassemblies, each occupant of a wheeled carrier may have the following self-propulsion equipment available: radially extending rotatable stroke handles, also called drive bars or drive levers, mountable outside of the large wheels on their shafts and movable through adjustable limit arcs to keep them within reach and having resilient securement clips at the limit stops of the arcs to hold them when not in use; adjustable position drive dog subassemblies mounted on the free ends of the respective stroke handles, including an adjustable head frame, forward and/or reverse driving dogs pivotally secured to the adjustable head frame and formed to grip the large wheel tire upon a propulsion stroke and to release its grip on the tire upon a return stroke, resilient retainers to selectively hold one or both of the forward and/or reverse driving dogs well clear of the tire, and hand gripping or manipulating drive handle units, each mounted on a respective adjustable head frame and having a sleeve rotatable about its own mounting pivot pin and mounted either firmly 2 or spring biased into radial alignment with the stroke handle; braking materials adjus'tably positioned on each stroke handle to be moved transversely into contact with a, large wheel or its handrim if so equipped; and retractable and extendable added length units of each stroke handle pivotally used during curb hopping or like maneuvers.

Any selected embodiment of these self-contained subassemblies for aiding an occupant of a wheeled carrier in his or her self-propulsion may be added to or subtracted from to provide a different embodiment. Moreover, the adjustability of these self-propulsion subassemblies enables a person to install them on many types of wheeled carriers, and at all times to do so without altering the initial design concepts of structure or operation of the original wheeled carrier. When the self-propulsion self-contained subassemblies are not to be used, the resilient holding of the stroke handles in an out of way position, returns the wheeled carrier for operation by an attendant who is assisting the occupant.

DRAWINGS OF PREFERRED EMBODIMENTS FIG. I is a perspective view ofa universal wheelchair showing an occupant commencing a forward propulsion stroke using the self-contained, self-propulsion subassemblies secured to the large wheel shafts;

FIG.2 is an exploded perspective view of the selfco ntained, self-propulsion subassembly, and portions of the large wheel, frame, and shaft or bearing bolt, of the universal wheelchair illustrated in FIG. 1; I

FIGS. 3 through 6, inclusively, schematically illustrate, using direction arrows, how an occupant undertakes a forward motion power stroke using, for example, the universal wheelchair illustrated in FIG. I, which is equipped with the self-contained. selfpropulsion subassemblies secured to the large wheel shafts, as shown in FIGS. 1 and 2, with FIG. 3 depicting the start position, FIG. 4 indicating the mid-position, FIG. 5 showing the end of the power stroke, and FIG. 6 illustrating the return to the start position;

FIGS. 7 and 8 schematically illustrate, using direction arrows, how the drive dog pivots to contact the tire of the large wheel of the wheeled carrier, such as the universal wheelchair shown in FIG. 1, with the drive dog of the self-propulsion subassembly shown in its full gripping and driving position in FIG. 7, and in its releasing and returning position in FIG. 8;

FIGS. 9 through 14, inclusively, schematically indicate, using direction arrows, how paired drive dogs used respectively in forward and reverse drive strokes are positioned, with FIG. 9 showing a forward driving stroke with the reverse driving dog held in its inactive position and the forward driving dog firmly gripping the tire of'the large wheel, with FIG. 10 showing the return from the forward driving stroke, with FIG. 11 illustrating a reverse driving stroke with the forward driving dog held in its inactive position and the reverse driving dog firmly gripping the tire of the large wheel, with FIG. 12 illustrating the return from the reverse driving stroke, with FIG. 13 showing both the forward and re verse driving dogs engaged with the tire of the large wheel which completely brakes the wheeled carrier, and with FIG. 14 illustrating both the forward and reverse driving dogs held in their inactive positions;

FIG. 15 is a partial perspective view, with portions removed, of both the wheeled carrier and the self propulsion subassembly, to illustrate, using direction arrows, how braking of the wheeled carrier occurs, as the stroke handle is moved transversely by the occupant toward the middle of thewheeled carrier causing the braking material, adjust-ably mounted on the stroke handle, to soon firmly contact the handrim of the large wheel and frictionally retard its motion;

FIG. 16, is a partial perspective view, with portions removed, of both the wheeled carrier and the selfpropulsion subassembly, to shown using direction arrows, how a hand gripping handle may be mounted for rotation about its own longitudinal axis and about its pivotal mounting, the hand gripping handle being returned to its radial in line position with the stroke handle upon its release by the actuation of the spring and its linkage;

FIGS. 17 and 18 show how adjustable stops and resilient holders are arranged for controlling the motion of the stroke handles, the partial perspective view of FIG. 17, with portions removed, illustrating the outside appearance of the disc brazed to the bearing bolt or wheel shaft and having spaced circumferential holes available outside of the large wheel of the wheeled carrier, to selectively receive forward and reverse limit subassemblies, further illustrated in the partial inside elevational view of FIG. 18, each subassembly comprising a screw or bolt held in place on the disc by a hexagonal headed nut which also serves the dualpurpose of stopping the motion of the stroke handles to establish their operat' ing are shown by the arrows, and each subassembly in cludes a resilient retainer to frictionally retain the stroke handle at one of the limitpositions;

FIG. 19 is a front view ofa collapsed universal chair, as illustrated before being collapsed in FIG. 1, wherein dimension lines and arrows are used to illustrate the very minimal addition to the width of the wheelchair necessitated by the installation of these self-propulsion, self-contained, subassemblies, which provide the occu pant with additional controls to aid in his or her selfpropulsion of the wheelchair;

FIGS. 20 and 21, in partial perspective views of portions of a wheelchair and the self-propulsion, selfcontained, subassemblies, illustrate the addition and adjustment of retractable and extendable additional length units of each stroke handle mounted in a retracted position as shown in FIG. 20, and mounted in an extended position as shown in FIG. 21, for pivoting in contact with the ground to movably support the wheelchair and the occupant during his or her curb hopping maneuvers;

FIGS. 22 through 28, schematically in side views and using direction arrows, illustrate how the additional length units of each stroke handle, illustrated in FIGS. 20 and 21, are utilized by the occupant in curb hopping or in a maneuver having a similar objective, with FIG. 22 showing the approach of a universal wheelchair to the curb, FIG. 23 showing with directional arrows, the turnaround of the'wheelchair and its contact with the curb using the large wheels, FIG. 24 illustrating, with a directional arrow, the extension and placement of the extendable and retractable additions to the stroke handles to contact the ground just above and slightly back from the street curb or other obstruction, FIG. 25 detilted the wheelchair backwardly to raise the pivot wheels to the curb height as the stroke handles were moved further in the reverse direction, the directional arrow further indicating the retraction of the stroke handles, FIG. 27 showing with a directional arrow the turnaround of the wheelchair, and FIG. 28, illustrating the occupant underway again on level or near level ground with the direction arrow showing the completion of a forward power stroke of the stroke handles;

FIG. 29 is a partial perspective view of a large wheel of a wheeled carrier and portions of another embodiment of the self-contained adjustable. self-propulsion, subassembly mounted to be adjacent to a large wheel, which'is not equipped with a handrim, illustrating how the braking material is formed to contact the rim and tire of the large wheel, how the tilting or pivoting of the hand grip handle occurs, and how the resilient drive dog retainer components appear while the drive dog pivots into contact with the tire;

FIG. 30 is a partial perspective view of a large wheel and handrim of a wheeled carrier and portions of another embodiment of the self-contained, adjustable, self-propulsion subassembly mounted to be adjacent to the handrim, illustrating how the handle grip is firmly secured to the head frame and consequently indirectly and firmly secured to the stroke handle to remain radially'in line with it, and also how the handle grip includes a hand surrounding strap, thereby making it more convenient for an occupant having reduced dexterity in his or her hands to nevertheless effectively operate the stroke handles for propulsion, turning, and stopping, the positioning of the braking material being shown opposite the handrim and also the positioning of the drive dog against the tire being shown, following its release from its cleared storage position maintained by the resilient drive dog retainer components;

FIG. 31, is a perspective view ofa traveler wheelchair illustrating how the self-contained, adjustable, selfpropulsion, subassembly is mounted on a wheelchair having the large wheels mounted in the front and the small pivoting wheels in the back; and

FIG. 32 is a perspective view of a wheelstretcher showing how the self-contained, adjustable, selfpropulsion, subassembly is mounted on a wheelstretcher having large wheels mounted at least at one end.

DESCRIPTION OF PREFERRED EMBODIMENTS The Self-Contained, Adjustable, Self-Propulsion Subassemblies are Quickly and Conveniently Mountable on Many Types of Wheeled Carriers to be Conveniently Operated by the Occupants Dr. Herman L. Kamenetz, M.D., in his book entitled, The Wheelchair Book" published in I969, by Charles C. Thomas Publisher at Springfield, Ill., describes and illustrates many wheeled carriers for persons who must use them to increase their mobility, following illnesses and accidents, for a time during a recovery period or during the remainder of their lifetime. When a person is still able to some degree to move his or her hands, arms, and shoulders, then a wheeled carrier may be selected having large wheels which may be equipped with these self-contained, adjustable, self-propulsion subassemblies. For example, the universal wheelchair having large wheels at the rear and pivoting smaller wheels at the front, see FIG. 1, the traveler wheelchair having large wheels at the front and pivoting smaller wheels at the rear, see FIG. 31, and the wheelstretcher' having large wheels at one end pivoting smaller wheels at the other end, see FIG. 32, may all be equipped quickly and conveniently with one or the other of the embodiments of the self-contained, adjustable, self-propulsion, subassemblies, illustrated and described herein. Although these self-propulsion subassemblies will better serve a person who retains considerable strength in his or her hands, arms, shoulder and trunk, the subassemblies equipped with strap handle grips as shown in FIG. 30, will serve a person quite well who has less strength and/or dexterity in his or her hands, etc.

Self-Contained, Adjustable, Self-Propulsion subassemblies For Forward Propulsion and Braking Mounted on a Universal Wheelchair In FIG. 1 in a perspective view, an occupant is shown in a universal wheelchair 40, one having large wheels 42 at the rear and smaller pivotal wheels 44 at the front, the latter often being referredto as casters. The frame 46 is made of bar materials having overall side members 48 which move toward one another as the transverse folding brace assembly 50, positioning the sides 48, is pivoted into a closed position when the wheelchair 40 is to be carried without the occupant and stored out of the way. The footrests 52 pivot and the back rest 54 and seat 56 are made foldable or pivotable to accommodate the folding of this universal wheelchair 40. To further accommodate this desirable folding capability of this conventional universal wheelchair 40 the shafts 58 of the large wheels 42 are cantilevered outwardly from the frame 46, and no cross axle is used. In so mounting the large wheels 42, these shafts 58 are generally bearing bolts 58 having a hexagonal head 60 and they are secured in position by threading their ends in the frame 46 of a wheelchair. Also a threaded portion of each bolt 58 protrudes beyond the frame 46 to receive a hexagonal headed lock nut 64 which creates a thread lock. As a direct consequence, these bearing bolts 58 are held so securely they do not turn.

In FIG. 2, in an exploded perspective view the quickly and convenient attachment of the selfcontained, adjustable, self-propulsion subassemblies 70 are illustrated as being undertaken at these shaft mountings of the large wheels 42. The bearing bolt 58 is interchanged with another bearing bolt 72 which has a disc 74 brazed to it at its hexagonal head 76. Before reassembly, limit stops 78 are selectively secured to respective holes 80 of many holes spaced circumferentially around disc 74, also referred to as the bolt plate 74. Each limit stop 78 to be contacted by the stroke handle 82 is composed of a screw or bolt 84 and a hexagonal headed nut 86. Before finally assembling and securing one limit stop 78 on each side, a resilient retainer 88 is fitted over the screw or bolt 84 to provide a place where a stroke handle 82 may be secured during times when the self-propulsion subassemblies are not being used. For example, when an attendant is pushing the wheelchair 40 or it is being stored away.

To position the stroke handle 82, also referred to as a drive bar or drive lever, sufficiently away from the large wheels 42, a clearance washer or washers 62 may be used. Also when the stroke handle 82 is made of softer material or for another reason, a hearing or bushing 90 may be used in the stroke handle 82 to thereafter rotatably contact the bearing bolt 72.

After arranging these components as indicated in FIG. 2, the self-propulsion subassemblies 70 are positioned and tightened in place upon turning the lock nut 64 about bearing bolt 72. At the conclusion of this securement the remainder of the components are then in their operating positions or nearly so for they all depend on this securement, utilizing the bearing bolt 72 with its brazed disc 74 and lock nut 64, to hold them in place relative to the universal wheelchair 40 which is only altered at this location by the interchange essentially of bearing bolt 58 for hearing bolt 72.

As noted further in FIG. 2, stroke handle 82 may have an offset portion 96 to maintain the clearance set by washer 62, especially if the large wheel 42 is equipped with a handrim 98 which has been described as a wheel in the middle of a wheel. When a handrim 98 is made a part of large wheel 42 then large wheel 42 is oftencalled a drive wheel or a propelling wheel. Although the addition of handrims 98 have added greatly to providing mobility to an occupant of a wheelchair 40, the addition of these self-contained, adjustable selfpropulsion subassemblies 70 has added the potential of much more mobility to an occupant of a wheelchair 40 so equipped with them.

As further illustrated in FIG. 2, above, at the upper end of the stroke handle 82, a head frame 100 is adjustably secured up or down within a limited distance by using paired threaded bolts 102 passing through a verti cal slot 106 in the stroke handle and into threaded holes, not visible in FIG. 2, in the head frame 100. A forward drive dog 110 is then pivotally supported to the receiving bottom 112 of this transverse head frame 100 by a threaded pivot pin 114 passing through holes 116 in the head frame 100, through hole 118 in the forward drive dog 110, and thereafter being threadably tightened in place in head frame 100. The receiving bottom 112 of head frame 100 has an additional receiving space 122 in which a resilient holding or receiving spring or clip 124 is permanently secured. An entry or retaining pin 126 permanently secured to the top 127 of forward drive dog 110 is releasibly held by the receiving or holding spring or clip 124 when the forward drive dog 110 is intentionally pivoted upwardly to its inactive position well clear of the tire 128 of the large wheel 42. The forward drive dog 110 is pivoted upwardly by using its extending finger gripping raised bevel end 130, which also first includes transverse gripping tooth edges 132 134, 136 and then sufficient extending body portions 138 to prevent the complete rotation of the forward drive dog during a propulsion stroke of the stroke handle 82. Also the upper transverse portion 140 of the forward drive dog 110 through which hole 118 is made is formed sufficiently offset to the top 127 of the drive dog 110 to permit its convenient clearance during non use times.

Also shown in FIG. 2, is the spring biased pivotal mounting of a further rotatable drive handle gripping subassembly 144 on the head frame 100, to thereafter aid the occupant in his or her movement of the stroke handle 82. A drive handle pivot pin 146 with a head 148 is inserted through a drive handle sleeve 150, having a hole 152 large enough to allow this sleeve to freely rotate about this pin 146. Tightly fitted to this sleeve 150 is a finger gripping cover 151. Then the pin 146 with its threaded end 154 is secured to a drive handle bracket 156 having the receiving threaded hole 158. The drive handle bracket 156 is formed with an upper horizontal plane surface 160 and a lower half round surface 162 and through its center is a hole 164. A cornerof the head frame 100 has a slot 166 and also a threaded hole 168 to receivie the drive handle bracket 156 for its securement using a threaded pivot pin 170. Also the head frame 100 has additional internal space 172, not 'shown in FIG. 2 but indicated in FIG. 16, to receive a biasing return spring and linkage subassembly 174 utilized to keep the spring biased pivotal mounting of the drive handle 144 in a radially in line position with the stroke handle 82, when it is not otherwise positioned by the occupant of the wheelchair 40. A small link 176 is secured at one end by a pin 178 to the drive handle bracket 156 and to a hole 180 in its other end an end of a coiled spring 182 is secured. Thereafter the other spring end of the coiled spring 182 is secured to a threaded pin 184 secured in head frame 100.

Also illustrated in FIG. 2, is the brake shoe material 190 slidably and firmly surrounding the stroke handle 82. It is positioned to firmly contact the handrim 98 when the drive handle is gripped and/or otherwise held and then moved toward the center of the wheelchair, causing the brake shoe material 190 to firmly bear against the handrim as shown in FIG. to create a braking action.

Operating the Wheelchair Equipped With the Self-Contained, Adjustable Self-Propulsion Subassemblies With the completion of the installation of the selfpropulsion Subassemblies 70, following the correct height adjustable of the head frame 100 to place the forward driving dog 110 in good contact with the tire 128 of large wheel 42, the correct height adjustments of the brake shoe materials 190 for their pressure contacts with the handrims 98, and the suitable placement of limit stops 78 for the overall travel of the stroke handle 82, the occupant is ready to get underway. In FIGS. 3 through 5 inclusively, the occupant is shown starting, undertaking, and completing, a forward power stroke, and in FIG. 6, the stroke handle 82 is being returned to commence another power stroke. The position ofthe forward driving dog 110 against the tire 128 during the power stroke is illustrated schematically in FIG. 7. The transverse gripping teeth edges 132, 134, and 136 substantially aid in the good contact that results. As indicated, the turning force helps to create a force couple which causes this forward driving dog 110 to bear firmly on the tire 128 of large wheel 42 as it pivots about its pivot pin 114. After the driving stroke is completed, upon the return stroke, the forward driving dog 110 oppositely pivots about pivot pin 114 and it is lightly dragged over the tire 128 of large wheel 42 as illustrated schematically in FIG. 8.

Utilization of Both Forward and Reverse Driving Dogs As shown schematically in FIGS. 9 through 14, both the forward and reverse driving dogs, 110 and 192, may be included in one self-propulsion subassembly 70. In FIGS. 9 through 10, the powerstroke and return stroke using the forward driving dogs 110 are illustrated, wherein a force is applied at the finger gripping cover 151 to move the stroke handle 82. In FIGS. 11 and 12, the power stroke and return stroke using the reverse driving dog 192 are illustrated, wherein a force is again applied at the finger gripping cover 151 to move the stroke handle 82. When both the forward driving dog and the reverse driving dog 192 are at the same time placed firmly in their driving position then movement of the stroke handle 82 is prevented, as illustrated schematically in FIG. 13. In contrast. in FIG. 14. both the forward driving dog 110 and the reverse driving dog 192 are pivoted upwardly by hand and resiliently held clear of tire 128 of large wheel 42. Then the selfcontained, adjustable, self-propulsion subassembly is not in the way during wheelchair operations when an attendant is pushing the wheelchair or the handrim is being used by the occupant.

Creating Braking Forces When Using the self-Contained, Adjustable, Self-Propulsion Subassemblies Spring Biased Pivotal Mountings of the Drive Handles By pivotal mounting the drive handle Subassemblies 144, an occupant ofa wheelchair 40 may place the subassembly of the finger gripping cover 151, drive handle sleeve 150, and its pivot pin in several selected positions as indicated in FIG. 16. At any selected angular position, the finger gripping cover 151 and the drive handle sleeve are rotatable about the drive handle pivot pin 146. Therefore at all times, the occupant is able to comfortably and conveniently grip a drive handle subassembly 144. Yet whenever the occupant releases the finger gripping cover 151, the drive handle subassembly 144 under force of spring 182 moves into radial alignment with the stroke handle 82 to keep the overall width of the wheelchair 40 as narrow as possible, as illustrated in FIGS. 16 and 19. Under the force of spring 182, this automatic return motion keeps the drive handle assemblies 144 well out of the way in a non-hazardous position.

Adjustment of the Overall Radial Movement of the Stroke Handles by Selectively Placing and Securing Limit Stops An occupant because of his or her size and/or strength selects the best operating arc range through which the'stroke handles 82 may be moved while they remain always within easy reach of the occupant. Or preferably and oftentimes his or her Doctor selects the operating range. Thereafter, as illustrated in FIGS. 2, 17, and 18, limit stop Subassemblies 78 are secured in place on the disc or bolt plate 74, which in turn has been brazed to bearing bolt 72. Each limit stop subassembly 78 has a bolt or screw 84 which passes through a selected hole 80 of many like spaced circumferentially located holes 80. Thereafter, the bolt or screw 84 is secured in place upon tightening a hexagonal headed nut 78 which is turned to fully contact the stroke handle 82. As noted previously, the bearing bolt 72 and its brazed, welded or integral disc or bolt plate 74, do not 9 turn, after the hexagonal headed lock nut 64 is tightened, thereby creating a thread lock in relation to the threaded portions of the bolt 72 which are threaded through the frame 46 and beyond to receive the lock nut 64.

Holding the Stroke Handles in Place When They are Not in Use As illustrated in FIGS. 2 and 18, a resilient retainer 88 is secured in place when one of the limit stop subas semblies 78 is being installed. When a stroke handle 82 is not to be used, for example, during movement of the folded universal wheelchair 40, or when the occupant in the wheelchair 40 is being guided and pushed around by an attendant, then the stroke handles 82 on each side of the wheelchair are removably placed in the resilient retainers 88.

Additional Braking is Available When an Occupant is Entering or Leaving a Wheelchair To keep a wheelchair 40 from moving beneath a person who is lowering and/or raising his or her body relative to the seat 56 of a wheelchair 40, the wheelchair 40 is generally locked by using a conventional wheel brake if there is one on a particular wheelchair, or by having an attendant firmly hold it against movement. To provide additional braking forces at these critical loading and unloading times, the respective driving

dogs

110 or 192 may be placed in their driving positions while at the same time the stroke handles 82 are moved against their respective limit stops, to thereby create and maintain good braking forces if the wheelchair attempts to move. If resilient retainers 88 are also available, the stroke handles 82 are also secured in them, while the pertinent driving dogs are held in their driving positions to thereby effectively grip the tire 128 and create the good braking forces so the wheelchair will not move out from under the occupant during entering or leaving.

Retractable, Extendable, Partially Telescoping, Extensions For the Stroke Handles to Enable the Occupant to Move His or Her Wheelchair Over or Like Obstruction As illustrated in FIGS. and 21, the self-contained, adjustable, self-propulsion, subassemblies 70, may re ceive a curb hopping subassembly 200. Then, as illustrated schematically in FIGS. 22' through 28, the occupant may raise himself or herself while seated in the wheelchair up and over a curb 202 or somewhat similar obstruction.

The stroke handle 82, if not originally provided with two spaced

edge notches

204, 206, one spaced below the other, is so modified along one edge to receive a spring biased lock pin 208, of the curb hopping subassembly, to thereby hold the curb hopping subassembly 200 in a retracted non use position above, or in an ex tended use position below. No other part modification is necessary. However during the installation of a selfpropulsion subassembly 70, the curb hopping subassembly 200 should be telescoped around the stroke handle 82 before the brake shoe material 190 and the head frame 100 are installed.

The curb hopping subassembly 200 has an elongated lever bar 210 slightly wider than the stroke handle 82, and ofthe same thickness. It is covered at its bottom by a protective and grip providing end cap 212. At its top,

it is formed with a larger portion 214 having a central hole 216 to slidably receive the upper portions of the stroke handle 82. To interlock the telescoping curb hopping elongated lever bar 210 with the stroke handle 82 at either the retracted position or extended position. using respectively

notches

204 and 206, the spring biased lock pin 208 is respectively aligned with one of these notches and it then moves under spring force into a locking position. Each lock pin 208 is mounted on one end of a leaf spring 218 which is positioned along the edge of the larger top portion 214 of the elongated lever bar 210, and it is secured to top portion 214 at its other spring end by a force fitting retaining pin 220. The flexure of leaf spring 218 is sufficient to permit the withdrawal oflock pin 208 from a

respective notch

204 or 206.

With the self-contained, adjustable, self-propulsion subassemblies 70 equipped with the curb hopping subassemblies 200, the occupant then is able to follow the curb hopping sequence, illustrated in FIGS. 22 through 28. He or she approaches the curb 202 and preferably turnsaround to position the rear large wheels 42 of a universal wheelchair 40 against the curb 202. This is the best approach rather than first tilting backwardly to raise the pivotal wheels over the curb and then follow on with the utilization ofthe curbing hopping subassembly 200. Following the preferable rear approach, after contact is made with the curb 202, FIG. 23, the curb hopping subassembly 200 is extended and rotated to place the end of the elongated lever bar 210 above and slightly beyond the curb 202, FIG. 24. Thereafter, upon pivoting the combined stroke handle 82 and elongated lever bar 200, FIG. 25, the rear large wheels 42 of the universal wheelchair 40 are rotated up and over the curb 202 transferring most of the weight of the wheelchair 40 and the occupant to the ground above and beyond the curb 202. Then at this time a slight tilting backwardly is undertaken as a pivoting force is applied at the finger gripping covers 151 and the wheelchair 40 and occupant reach the position at the new ground level well removed from the curb 202. Thereaf- Mounting of Self-Contained Adjustable, Self-Propulsion Subassemblies on Wheelchairs Without Handrims As illustrated in FIG. 29, the large wheels 42of a universal wheelchair 40, or other wheeled carrier such as a traveler chair 222, FIG. 31, or a wheelstretcher 224, FIG. 32, may not be made with the addition of a handrim 98. If so, the brake shoe material must be remolded or shaped to provide the extended brake shoe material 226 shown in FIG. 29. The portions are shaped to conform to the partial side contour of the rim 228 and tire 128 of the large wheel 42.

Non Pivotal, Yet Rotatable Strapped Drive Handle Subassemblies Some occupants, although having some strength to self-propel themselves, do not have sufficient dexterity in their hand to grip drive handle subassemblies 144 which pivot and rotate. Therefore, as illustrated in FIG. 30, a drive handle subassembly 230 is provided which does not pivot and has a helpful hand strap 232. However, the finger gripping cover 151 on the drive handle sleeve 150 does rotate about the drive handle pivot pin 146, as previously illustrated in FIGS. 2 and 16. In this embodiment, the drive handle pivot pin 146 is threaded directly into a hole in the modified head frame 234.

Mounting of Self-Contained, Adjustable, SelfPropulsion Subassemblies on Other Wheeled Carriers, Such as Traveler Chairs and Wheelstretchers Although the mounting of the self-contained, adjustable, self-propulsion subassemblies 70 has been previously described in reference to universal wheelchairs 40, these subassemblies 70 are also mounted on traveler wheelchairs 222, as illustrated in FIG. 31. Also these subassemblies 70 are installed on the large wheels 42 of a wheelstretcher 224, as shown in FIG. 32.

Summary of Advantages of Manufacturing, Installing, and Using, the Self-Contained, Adjustable,- Self-Propulsion Subassemblies There is one change made in the structure of present wheeled carriers having at least two large wheels 42, when installing these self-contained, adjustable, self propulsion subassemblies 70. It is the interchange of the large wheel shafts or bearing

bolts

58, 72. The new bearing bolts 72 with disc 74, replace the original bearing bolts 58. Beyond this shaft change there are few concerns about different designs of present wheeled carriers. Variations in present wheel diameters of wheelchairs is undertaken in approximately 2 inches changes by offering different stroke handle sizes. Then further variations to accommodate, for example, hard rubber or semi-pneumatic tires, etc., are undertaken by adjusting the mounting of head frame 100 on the stroke handle 82. Also variations in wheel widths are provided by using spacing washers 62 and the off-set portion 96 of the stroke handle 82. These self-propulsion subassemblies 70 are designed to be very effective in operation, easily shipped, assembled, installed and serviced. The standardization of the components, there being no initial distinction between left and right parts, reduces costs throughout the manufacture, storage, handling, shipping and parts inventory and supply.

These advantages are all gained without detracting from the primary purpose of providing these selfpropulsion subassemblies 70 for wheeled carriers having at least two large wheels 42, to give the occupant of the wheeled carrier more mobility in moving himself or herself, than previously made available to him or to her, for example, by the addition of handrims 98, and the components described and illustrated in prior patents and books. The occupant may now move the

wheelchair

40, 222 or other wheeled carrier conveniently, quickly, accurately and comfortably. The occupants hands are more effective when gripping the finger cover 151 and its subassembly 144, and thereafter propelling, stopping, turning, braking, and holding the wheeled carrier, than previously when the occu- 12 pants hands directly moved the handrim 98 or operated mechanisms developed previously by others.

The occupant in gripping the pivotal drive handle subassemblies 144 for persons having good dexterity in their hands, or the non pivotal handle subassemblies 230 having straps 232, for persons having poor dexterity in their hands does so over a period of time without causing any undue stresses ofhis fingers and hands. because his or her gripping or holding action is a natural one. Gone is the prospect of the thumb hitting the supports of a handrim 98, etc. which has led to unusual re development of muscles of the thumb and fingers. Moreover, at all times the

handle subassemblies

144 or 230 may be kept cleaner in contrast to handling of tires 128 directly or to a lesser extent the handling of the handrims 98.

Although the stroke handles 82 will generally be used as forces are applied at the

handle subassemblies

144 or 230 to cause the

dogs

110 or 192 to grip the tires 128 during a power stroke, in close quarters and/or during low speed maneuvers, the stroke handles 82 may be pulled toward handrims 98 and/or wheels 42, so the

braking materials

190 or 226 may be used to first grip the handrims 98 and/or wheels 42. Then, when these

braking materials

190 and 226 are so held in their gripping positions, the stroke handles 82 are rotated forwardly or backwardly together, or opposite one another, or one at a time, to maneuver the wheeled carrier. Also, if a universal wheelchair 40, for example, is only equipped with forward driving dogs 110, then during reversing, this propulsion use of the

braking materials

190 or 226 may be undertaken.

During these braking material propulsion maneuvers, the driving digs or 192 may be fully cleared of tires 128 by using their retainer pins 126 and resilient springs or clips 124, or they may be left to idle over the tires 128. Unless a regular power stroke is'being undertaken, the unretained, driving

dogs

110 or 192 will always be in an idle or low drag position. Just as soon as a power stroke is completed, the continuing on motion of a wheel 42, automatically clears a driving

dog

110 or 192 into its idle position.

When an occupant has considerable strength in his hands, arms, shoulders and trunk, and his Doctor has no reason to control his possible potential ability to gain considerable speed, the occupant after starting his or her

wheelchair

40 or 222 with one or more synchronized motionsof stroke handles 82, may thereafter alternate the motions on the left or right side, similar in left or right motions of oars undertaken during rowing of a boat.

In contrast to propelling himself or herself, if necessary, during braking, a very strong inward thrusting of the stroke handles 82 will move the braking materials or 226 into sufficient frictional contact to skid the tires 128 making a very abrupt stop. Also during coasting slight pressures applied on the left and right side together are used for limited deacceleration. Moreover, slight pressures alternately applied on the right or left sides are used for directional control during coasting.

As noted in discussing curb hopping, the approach to a curb 202 using the large wheels 42, for example, of a universal wheelchair 40, is preferred. Likewise, in climbing up a ramp, the occupant may prefer to back up his or her universal wheelchair 40, or other wheeled carrier, remaining in better balance and under better control, using these self-contained adjustable selfpropulsion subassemblies 70.

Therefore, with all these operational advantages, the modern wheelchair which has previously been described by others as an extension ofthe occupants body, now is extended further while maintaining his or her comfort and saftey. Moreover, this is accomplished at a comparatively low cost of manufacture, installation and service.

I claim:

1. A self-propulsion subassembly, which is selfcontained and adjustable, for installation in pairs on wheeled carriers such as wheelchairs and wheelstretchers for the occupant to use in applying control forces to large wheels, comprising:

a. astroke handle for radial operation having a hole at its bottom to be fitted over a wheel bearing bolt positioned horizontally on a wheeled carrier and a hole near its top to adjustably receive a head frame;

a head frame adjustably secured with its fasteners at the hole of the stroke handle in a transverse position and formed both with a receiving bottom, and with holes to receive fasteners and a pivot pin;

c. a driving dog positioned to contact a large wheel of a wheeled carrier and pivotally installed in the receiving bottom of the head frame by being formed with a transverse hole in which it has a pivot pin which in turn is secured in holes in the head frame;

d. a handle secured to the head frame; and

e. a braking shoe material placed on the stroke handle in a position to be transversely moved against a large wheel of a wheeled carrier to create a braking force.

2. The self-propulsion subassembly for installation on wheeled carriers, as claimed in claim 1, wherein the braking shoe material is positioned not only to be effective during braking, but to be also effective to create a propulsion force during slower maneuver undertaken generally in crowded places.

3. A self-propulsion subassembly, which is selfcontained and adjustable, for installation in pairs on wheeled carriers such as wheelchairs and wheelstretchers for the occupant to use in applying control forces to large wheels, comprising:

a. a stroke handle for radial operation having a hole at its bottom to be fitted over a wheel bearing bolt positioned horizontally on a wheeled carrier and a hole near its top to adjustably receive a head frame;

b. a head frame adjustably secured with its fasteners at the hole of the stroke handle in a transverse position and formed both with a receiving bottom, and with holes to receive fasteners and a pivot pin;

c, a driving dog positioned to contact a large wheel of a wheeled carrier and pivotally installed in the receiving bottom of the head frame by being formed with a transverse hole in which it has a piovt pin which in turn is secured in holes in the head frame;

d. a handle secured to the head frame; and

e. limit stops secured to another wheel bearing bolt which is then substituted for a conventional wheel bearing bolt of a wheeled carrier, to thereafter limit the radial movement of the stroke handle keeping it within the reach of an occupant of the wheeled carrier.

4. The self-propulsion subassembly for installation on' wheeled carriers, as claimed in claim 3, wherein a fastener is mounted with a limit stop to resiliently hold the stroke handle in a non use position.

5. A self-propulsion subassembly, which is selfcontained and adjustable, for installation in pairs on wheeled carriers such as wheelchairs and wheelstretchers for the occupant to use in applying control forces to large wheels, comprising:

b. a head frame adjustably secured with its fasteners at the hole of the stroke handle in a transverse posi tion and formed both with a receiving bottom, and with holes to receive fasteners and a pivot pin;

d. a handle secured to the head frame; and

e. a disc secured to the head of another wheel bearing bolt which is then subsituted for a conventional wheel bearing bolt of wheeled carrier, and the disc has spaced circumferential holes, and limit stops are selectively secured in two of the spaced circumferential holes to limit the stroke handle movement to keep it within the occupants reach.

6.- A self-propulsion subassembly, which is selfcontained and adjustable, for installation in pairs on wheeled carriers such as wheelchairs and wheelstretchers for the occupant to use in applying control forces to large wheels, comprising:

c. a driving dog positioned to contact a large wheel of a wheeled carrier and pivotally installed in the receiving bottom of the head frame by being formed with a transverse hole in which it has a pivot pin which in turn is secured in holes in the head frame; and

d. a handle secured to the head. frame, having portions of the handle which are rotatable relative to one another about the major axis of the handle, also having portions of the handle which are pivotal relative to one another about an axis perpendicular to the major axis of the handle, and in addition having spring means included in each handle to return the handle to be in alignment with the stroke handle, thereby keeping the overall wheel carrier width to a minimum and eliminating any chance of a projecting handle from becoming a hazard, for

example, when goirlg thropghgoorways.

Claims

1. A self-propulsion subassembly, which is self-contained and adjustable, for installation in pairs on wheeled carriers such as wheelchairs and wheelstretchers for the occupant to use in applying control forces to large wheels, comprising: a. a stroke handle for radial operation having a hole at its bottom to be fitted over a wheel bearing bolt positioned horizontally on a wheeled carrier and a hole near its top to adjustably receive a head frame; a head frame adjustably secured with its fasteners at the hole of the stroke handle in a transverse position and formed both with a receiving bottom, and with holes to receive fasteners and a pivot pin; c. a driving dog positioned to contact a large wheel of a wheeled carrier and pivotally installed in the receiving bottom of the head frame by being formed with a transverse hole in which it has a pivot pin which in turn is secured in holes in the head frame; d. a handle secured to the head frame; and e. a braking shoe material placed on the stroke handle in a position to be transversely moved against a large wheel of a wheeled carrier to create a braking force.

3. A self-propulsion subassembly, which is self-contained and adjustable, for installation in pairs on wheeled carriers such as wheelchairs and wheelstretchers for the occupant to use in applying control forces to large wheels, comprising: a. a stroke handle for radial operation having a hole at its bottom to be fitted over a wheel bearing bolt positioned horizontally on a wheeled carrier and a hole near its top to adjustably receive a head frame; b. a head frame adjustably secured with its fasteners at the hole of the stroke handle in a transverse position and formed both with a receiving bottom, and with holes to receive fasteners and a pivot pin; c. a driving dog positioned to contact a large wheel of a wheeled carrier and pivotally installed in the receiving bottom of the head frame by being formed with a transverse hole in which it has a piovt pin which in turn is secured in holes in the head frame; d. a handle secured to the head frame; and e. limit stops secured to another wheel bearing bolt which is then substituted for a conventional wheel bearing bolt of a wheeled carrier, to thereafter limit the radial movement of the stroke handle keeping it within the reach of an occupant of the wheeled carrier.

4. The self-propulsion subassembly for installation on wheeled carriers, as claimed in claim 3, wherein a fastener is mounted with a limit stop to resiliently hold the stroke handle in a non use position.

5. A self-propulsion subassembly, whIch is self-contained and adjustable, for installation in pairs on wheeled carriers such as wheelchairs and wheelstretchers for the occupant to use in applying control forces to large wheels, comprising: a. a stroke handle for radial operation having a hole at its bottom to be fitted over a wheel bearing bolt positioned horizontally on a wheeled carrier and a hole near its top to adjustably receive a head frame; b. a head frame adjustably secured with its fasteners at the hole of the stroke handle in a transverse position and formed both with a receiving bottom, and with holes to receive fasteners and a pivot pin; c. a driving dog positioned to contact a large wheel of a wheeled carrier and pivotally installed in the receiving bottom of the head frame by being formed with a transverse hole in which it has a pivot pin which in turn is secured in holes in the head frame; d. a handle secured to the head frame; and e. a disc secured to the head of another wheel bearing bolt which is then subsituted for a conventional wheel bearing bolt of wheeled carrier, and the disc has spaced circumferential holes, and limit stops are selectively secured in two of the spaced circumferential holes to limit the stroke handle movement to keep it within the occupant''s reach.

6. A self-propulsion subassembly, which is self-contained and adjustable, for installation in pairs on wheeled carriers such as wheelchairs and wheelstretchers for the occupant to use in applying control forces to large wheels, comprising: a. a stroke handle for radial operation having a hole at its bottom to be fitted over a wheel bearing bolt positioned horizontally on a wheeled carrier and a hole near its top to adjustably receive a head frame; b. a head frame adjustably secured with its fasteners at the hole of the stroke handle in a transverse position and formed both with a receiving bottom, and with holes to receive fasteners and a pivot pin; c. a driving dog positioned to contact a large wheel of a wheeled carrier and pivotally installed in the receiving bottom of the head frame by being formed with a transverse hole in which it has a pivot pin which in turn is secured in holes in the head frame; and d. a handle secured to the head frame, having portions of the handle which are rotatable relative to one another about the major axis of the handle, also having portions of the handle which are pivotal relative to one another about an axis perpendicular to the major axis of the handle, and in addition having spring means included in each handle to return the handle to be in alignment with the stroke handle, thereby keeping the overall wheel carrier width to a minimum and eliminating any chance of a projecting handle from becoming a hazard, for example, when going through doorways.