Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61G—TRANSPORT, PERSONAL CONVEYANCES, OR ACCOMMODATION SPECIALLY ADAPTED FOR PATIENTS OR DISABLED PERSONS; OPERATING TABLES OR CHAIRS; CHAIRS FOR DENTISTRY; FUNERAL DEVICES
  • A61G5/00—Chairs or personal conveyances specially adapted for patients or disabled persons, e.g. wheelchairs
  • A61G5/10—Parts, details or accessories
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61G—TRANSPORT, PERSONAL CONVEYANCES, OR ACCOMMODATION SPECIALLY ADAPTED FOR PATIENTS OR DISABLED PERSONS; OPERATING TABLES OR CHAIRS; CHAIRS FOR DENTISTRY; FUNERAL DEVICES
  • A61G5/00—Chairs or personal conveyances specially adapted for patients or disabled persons, e.g. wheelchairs
  • A61G5/10—Parts, details or accessories
  • A61G5/1083—Quickly-removable wheels

Definitions

• This invention concerns improvements in wheelchairs, and more particularly relates to an improved wheelchair wherein the wheelchair-reliant person can without assistance modify the dimensional and mobility charac- (10) teristics of said wheelchair.
• Wheelchairs are generally constructed having a pair of small forward wheels, each supported by an overhead pivoted yoke which permits the wheel to turn 360° about (15) a vertical axis, and a pair of opposed large rear wheels positioned at each side of the chair on horizontally disposed axles which permit rotation of said rear wheels in fixed vertical planes.
• the rear wheels when simul ⁇ taneously pushed or pulled by the disabled occupant (20) propel the wheelchair in forward or rearward directions. When one rear wheel is pushed more than the other, or when one rear wheel is pushed while the other is maintained motionless or pulled in the reverse direction, the wheelchair can be made to perform turning motions.
• Wheelchairs having removable rear wheels have been disclosed in U.S. Patent 4,098,521 and elsewhere. (5) Although removal of the rear wheels substantially converts the wheelchair from a self-propelled to an attendant- propelled state, the feature of optional removability of the rear wheels affords the following advantages: a) easier storage of the wheelchair, particularly in (10) an automobile, b) eliminates the need of the user to lift or be lifted above the top of the rear wheels for side ⁇ ways transfer from or to the seat which is gener ⁇ ally below the top of the rear wheels, and
• an improvement in an otherwise conventional wheelchair comprised of a frame having paired rear vertical posts, front caster wheels mounted on said frame, seating means associated with said frame generally behind and above said front caster wheels, and a pair of rear drive wheels rotatably supported by said rear vertical posts on oppo-
• the improvement of the present invention comprises jacking apparatus capable of lifting at least the rear portion of the wheelchair to an elevated height where said drive wheels are no longer resting upon the support (5) surface for said wheelchair, and a pair of rear caster wheels, journalled to said frame in association with said jacking apparatus in a manner to engage said support surface when the rear portion of the wheelchair is lifted.
• the jacking apparatus is preferably associated with the
• axles of said drive wheels (10) axles of said drive wheels.
• Lever components of said jacking apparatus are situated within reach of the occu ⁇ pant seated in the wheelchair, and are adapted for movement in a substantially vertical plane to cause the jacking apparatus to raise or lower the rear caster
• the rear caster wheels are telescopically engaged with the frame in a downwardly directed manner such that, when not in operative position,
• the distance between the center of the drive wheel axle and the lowermost portion of an associated rear caster wheel is less than the radius of the drive wheel. In such non-operative or standby position, the rear caster wheels do not contact the support surface.
• the wheelchair may be of a conventional foldable construction, and said seating means may have flexible seatrest and backrest portions.
• Removable foot and leg (5) supports may be associated with the forward end of the wheelchair.
• Armrest members may be associated with said seating means, and clothing protectors may be vertically disposed between said armrest members and the lowermost extremity of said seating means.
• a circular handrail (10) may be coaxially disposed about each of said drive wheels to facilitate their manipulation.
• caster wheel as employed herein, is intended to denote a wheel pivotably mounted from above in a manner permitting rotation in a vertical plane and (15) 360° of turning about a vertical-.axis.
• the manner of mounting generally involves a yoke which spans said wheel in engagement with opposite extremities of the wheel's horizontally disposed axle, and pivotably engages an overhead support.
• said wheelchair when the rear caster wheels are activated to support the wheel ⁇ chair, said wheelchair is capable of movement in any direction whether or not the drive wheels are removed because it is supported by four caster wheels.
• movement of the wheelchair is accomplished by the occupant by applying pulling or pushing force to nearby objects such as walls in a confined area.
• the lever-operated jacking apparatus may be installed onto newly manufactured wheelchairs designed to accommo- (30) date said jacking apparatus, or said jacking apparatus, with slight structural modification, may be adapted for installation onto existing conventional wheelchairs.
• Figure 1 is a rear perspective view of a wheelchair equipped with an embodiment of jacking apparatus of the present invention, showing said wheelchair in its upwardly jacked position.
• Figure 2 is an enlarged fragmentary sectional view taken along the line 2-2 of Figure 1, showing the wheel ⁇ chair in its upwardly jacked position.
• Figure 3 is an enlarged fragmentary side view taken along the* line 3-3 of Figure 1 with the drive wheel (20) removed and showing the wheelchair in its lower, u jacked position.
• Figure 4 is a side view taken along the line 4-4 of Figure 2.
• Figure 5 is an enlarged sectional view taken along (25) the line 5-5 of Figure 1.
• a wheelchair is shown comprised of a metal tubular frame 10 having paired front vertical posts 11 and paired rear vertical posts 12.
• Diagonal support members 13 extending between lower horizontal connecting members 15 and upper horizontal connecting members 16 of frame 10 are interengaged by pivot pin 14 which enables the wheelchair to undergo a (5) folding-type motion causing lateral compaction thereof.
• Front caster wheels 17 engage the lowermost extremities of front vertical posts 11.
• seating means 20 comprised of back sling 18 and seat sling 19 fabricated of compliant (10) web-like materials and supported by portions of said frame.
• a pair of spoked rear drive wheels 21 having horizontally disposed hubs 22 and associated axles 30 are adapted for rotation in vertical planes about said axles.
• a lever-operated jacking device 23 is associated (15) with each rear vertical post 12 on the innermost or facing sides of said posts.
• the exemplified embodiment of jacking device shown in detail in Figures 2-4 is designed to be applied as an accessory feature to conven ⁇ tional wheelchairs.
• Said jacking device is comprised of (20) a support bracket 31 adapted to be fastened to post 12 by bolt 32 which penetrates channel 33 in said post and is secured by thread in bracket 31.
• a buttressing protru ⁇ sion 43 affixed to bracket 31 engages post 12 to prevent rotation of said bracket about bolt 32.
• An axle housing ( 25 ) 35 in said bracket disposed within protrusion 43 and parallel to channel 33 is adapted to provide journalled support for axle 30 of drive wheel 21.
• a lever 24 is attached to bracket 31 by first pivot means 25, thereby permitting pivotal movement of said lever in a vertical ( 30 ) plane.
• the forward ost portion of said lever is f OMPI designated action portion 44, and the rearwardmost portion of said lever is designated handle 39.
• a vertical connecting rod 26 is pendantly attached by a (5) second pivot means comprised of bushing 47 and pin 40 attached to said lever in action portion 44.
• the lower ⁇ most extremity of said vertical connecting rod engages a third pivot means comprised of bushing 46 and horizon ⁇ tally disposed pin 27 attached to column 28 which
• (10) supports rear caster wheel 29.
• Column 28 is adapted to telescopically engage tubular housing 30 pendantly supported by sleeve 37 fitted onto horizontal connecting member 15 and joined thereto by bolts 38.
• connecting rod 26 is
• said connecting rod may be provided with a knurled surface.
• lever 24 When the jacking device is activated to cause lift ⁇ ing, lever 24 will be in a substantially horizontal position, as shown in Figure 2. In said position, it is
• first pivot means 25 is above second pivot means 40, and the lever is in abutment with the innermost extremity of axle housing 35 which emerges from the inside face 45 of buttressing protrusion 43. Such manner of abutment prevents further downward movement
• the position of the second pivot means with respect to the first pivot means, and the angle of connecting rod 26 between said second and third pivot means are such that forces directed upwardly from (5) rear caster wheel 29 urge lever 24 in the direction of abutment with axle housing 35.
• Such factors of design and construction thereby constitute locking means which concertively act to maintain lever 24 in a fixed hori ⁇ zontal position.
• the elements of said locking means (10) comprise an abutment means such as axle housing 35, and a force emanating from rear caster wheel 29 and trans ⁇ mitted to said second pivot means in a manner serving to pivot said lever about said first pivot means in the direction of said abutment means.
• Properly directed force (15) transmission to the second pivot means may be secured by either proper placement of the second pivot means with respect to the first pivot means, or proper angle of the connecting rod.
• first and second pivot means are essentially the distance between the uppermost and lowermost positions of the rear caster wheel. It is to be noted that, when lever 24 is in its upright position as shown in Figure 3, first and second pivot means are centered on a substan- (25) tially horizontal line.
• the rear caster wheel instead of being mounted on a sleeve-like (5) fitting adapted to fit onto the lower horizontal connecting member, may be telescopi ⁇ ally fitted to an extension of rear vertical post 12 below said lower horizontal connecting member. Furthermore, certain features of the bracket member may be incorporated into
• Braking means operable by the seated occupant of the wheelchair may be provided to afford greater control over the motion of the wheelchair when it is in its jacked-up mode and capable of omnidirectional movement.
• Such braking means may be lever-activated devices which cause frictional restraint between the frame and the ground or rear caster wheels.
• axle 30 axle 30.
• a detent 54 which extends outwardly from axle 30 and communicates with channel 51 is associated with a tensioned spring 55 which maintains a force on detent 54 tending to draw it inwardly toward channel 51.
• the inner (5) end of said detent is normally in abutment with the cylindrical surface of rod 50, said abutment causing the outer end of said detent to protrude from axle 30.
• rod 50 is pressed toward the closed end of axle 30, a depressed portion 56 is brought beneath (10) detent 54.
• Such action causes detent 54 to temporarily enter axle 30,- thereby releasing axle 30 and its asso ⁇ ciated drive wheel from fixed engagement with axle housing 35.

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• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Handcart (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=23034340

Family Applications (1)

Country Status (3)

Families Citing this family (6)

Family Cites Families (7)

• 1982
  • 1982-05-24 WO PCT/US1982/000705 patent/WO1982004231A1/en unknown
  • 1982-05-24 EP EP82902126A patent/EP0081564A1/de not_active Withdrawn
  • 1982-06-07 CA CA000404621A patent/CA1192482A/en not_active Expired

Non-Patent Citations (1)

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