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A shock absorption mechanism for a wheelchair includes a caster fork including a first oblique surface and a second horizontally disposed surface, relative to a horizontal plane of travel of the wheelchair. A portion of the second surface includes a curved profile. A joint is mountable adjacent a fi

A shock absorption mechanism for a wheelchair includes a caster fork including a first oblique surface and a second horizontally disposed surface, relative to a horizontal plane of travel of the wheelchair. A portion of the second surface includes a curved profile. A joint is mountable adjacent a first section thereof to a frame of the wheelchair and adjacent a second section thereof to the caster fork. The joint includes a first oblique surface and a second surface for guiding reciprocation of the curved profile portion of the caster fork. A shock absorber is disposed in an oblique orientation between the first oblique surface of the caster fork and the first oblique surface of the joint. The caster fork is pivotable adjacent the second section of the joint. The shock absorber is compressable in a direction generally parallel to the oblique orientation thereof during pivoting of the caster fork.

대표청구항 ▼

1. A shock absorption mechanism usable in a wheelchair, said mechanism comprising:a caster fork including a first oblique surface and a second surface, each of said surfaces being disposed at first and second angles, respectively, relative to a generally horizontal plane of travel of the wheelchair,

1. A shock absorption mechanism usable in a wheelchair, said mechanism comprising:a caster fork including a first oblique surface and a second surface, each of said surfaces being disposed at first and second angles, respectively, relative to a generally horizontal plane of travel of the wheelchair, a portion of said second surface including a generally curved profile, said caster fork being pivotable about a first axis; a joint mountable adjacent a first section thereof to a frame of the wheelchair and adjacent a second section thereof to said caster fork by means of a pivot connection having a pivoting axis substantially collinear with said first axis for enabling reciprocation of said caster fork about said first axis, said joint including a first oblique surface relative to the generally horizontal plane of travel of the wheelchair, and further including a second surface for guiding reciprocation of said generally curved profile portion of said caster fork about said first axis; and at least one shock absorber mountable at one end thereof to said first oblique surface of said caster fork and at the other end thereof to said first oblique surface of said joint, said shock absorber disposable in an oblique orientation relative to the generally horizontal plane of travel of the wheelchair, wherein, said caster fork is pivotable in a predetermined direction about said first axis adjacent said second section of said joint when mounted adjacent said second section of said joint, and said shock absorber is compressable in a direction generally parallel to said oblique orientation thereof during pivoting of said caster fork, when mounted between said first oblique surface of said caster fork and said first oblique surface of said joint. 2. A mechanism according to claim 1, wherein said first angle is greater than approximately 1° and less than approximately 89° relative to the generally horizontal plane of travel of the wheelchair.3. A mechanism according to claim 1, wherein said second surface of said caster fork is disposed generally parallel relative to the generally horizontal plane of travel of the wheelchair.4. A mechanism according to claim 1, wherein said second angle is greater than approximately 1° relative to the generally horizontal plane of travel of the wheelchair.5. A mechanism according to claim 1, wherein when said caster fork is mounted to said joint, said first oblique surface of said caster fork is disposed generally parallel to said first oblique surface of said joint.6. A mechanism according to claim 1, wherein when said shock absorber is mounted between said caster fork and said joint, said shock absorber is disposed generally orthogonal relative to said first oblique surface of said caster fork.7. A mechanism according to claim 1, wherein when said shock absorber is mounted between said caster fork and said joint, said shock absorber is disposed at a predetermined angle relative to said first oblique surface of said caster fork.8. A mechanism according to claim 1, wherein:said caster fork includes a first cutout therein for affixation of a wheelchair wheel, said first cutout being defined by two first mirror-image extensions, the wheelchair wheel being affixable between each of said first mirror-image extensions, said joint includes a protrusion for insertion within a second cutout in said caster fork, said second cutout being defined by two second mirror-image extensions, said protrusion of said joint being insertable between each of said second mirror-image extensions, and said shock absorber being retained within indentations provided on at least one of said first oblique surfaces of said caster fork and said joint. 9. A mechanism according to claim 1, wherein said shock absorber is made of polyurethane elastomer.10. A method of absorbing impact shocks for a wheelchair, said method comprising the steps of:providing a caster fork including a first oblique surface and a second surface, each of said surfaces being disposed at first and second angles, respectively, relative to a generally horizontal plane of travel of the wheelchair, a portion of said second surface including a generally curved profile, said caster fork being pivotable about a first axis; mounting a joint adjacent a first section thereof to a frame of the wheelchair and adjacent a second section thereof to said caster fork by means of a pivot connection having a pivoting axis substantially collinear with said first axis for enabling reciprocation of said caster fork about said first axis, said joint including a first oblique surface relative to the generally horizontal plane of travel of the wheelchair, and further including a second surface for guiding reciprocation of said generally curved profile portion of said caster fork about said first axis; and mounting at least one shock absorber, in an oblique orientation relative to the generally horizontal plane of travel of the wheelchair, at one end thereof to said first oblique surface of said caster fork and at the other end thereof to said first oblique surface of said joint, wherein, when said caster fork pivots about said first axis adjacent said second section of said joint, said shock absorber compresses in a direction generally parallel to said oblique orientation thereof. 11. A method according to claim 10, wherein said first angle is greater than approximately 1° and less than approximately 89° relative to the generally horizontal plane of travel of the wheelchair.12. A method according to claim 10, wherein said second surface of said caster fork is disposed generally parallel relative to the generally horizontal plane of travel of the wheelchair.13. A method according to claim 10, wherein said second angle is greater than approximately 1° relative to the generally horizontal plane of travel of the wheelchair.14. A method according to claim 10, wherein said first oblique surface of said caster fork is disposed generally parallel to said first oblique surface of said joint.15. A method according to claim 10, wherein said shock absorber is disposed generally orthogonal relative to said first oblique surface of said caster fork.16. A method according to claim 10, wherein said shock absorber is disposed at a predetermined angle relative to said first oblique surface of said caster fork.17. A method according to claim 10, further including the steps of:providing a first cutout in said caster fork for affixation of a wheelchair wheel, said first cutout being defined by two first mirror-image extensions, the wheelchair wheel being affixable between each of said first mirror-image extensions; providing a protrusion on said joint for insertion within a second cutout in said caster fork, said second cutout being defined by two second mirror-image extensions, said protrusion of said joint being insertable between each of said second mirror-image extensions; and providing indentations on at least one of said first oblique surfaces of said caster fork and said joint for retention of said shock absorber in said indentations. 18. A method according to claim 10, wherein said shock absorber is made of polyurethane elastomer.19. A shock absorption mechanism usable in a wheelchair, said mechanism comprising:a caster fork including a first generally oblique surface and a second surface, each of said surfaces being disposed at first and second angles, respectively, relative to a generally horizontal plane of travel of the wheelchair, a portion of said second surface including a generally curved profile, said caster fork being pivotable about a first axis; a joint mountable adjacent a first section thereof to a frame of the wheelchair and adjacent a second section thereof to said caster fork by means of a pivot connection having a pivoting axis substantially collinear with said first axis for enabling reciprocation of said caster fork about said first axis, said joint including a first oblique surface relative to the generally horizontal plane of travel of the wheelchair, a second surface for guiding reciprocation of said generally curved profile portion of said caster fork about said first axis, and further including a cylinder having a central axis disposed generally orthogonal to said first oblique surface of said joint, said cylinder having a first open end and a second end having a passage for supplying air from an air filler valve to said cylinder; and a piston disposable within said cylinder, said piston having a first section disposed within said cylinder and a second exposed section protruding through said first open end of said cylinder and contacting said first generally oblique surface of said caster fork, said first section including at least one o-ring for providing sealing contact between said piston and said cylinder so as to prevent air from exiting said cylinder adjacent said piston, wherein, said caster fork is pivotable in a predetermined direction about said first axis adjacent said second section of said joint when mounted adjacent said second section of said joint, said piston is movable within said cylinder during pivoting of said caster fork when disposed within said cylinder and slidable along said first surface of said caster fork during reciprocation of said caster fork, and air pressure within said cylinder being adjustable to limit movement of said piston. 20. A mechanism according to claim 19, wherein said second section of said piston includes a roller mounted thereto, said roller being in one of rolling and sliding contact with said first generally oblique surface of said caster fork.