초록 ▼

The back of a wheelchair user is independently supported along and about three mutually perpendicular axes. Two elongated adjustment arms are pivotally connected to extension arms which telescope into opposite ends of a hollow connecting tube. The support positions along and about the three axes is

The back of a wheelchair user is independently supported along and about three mutually perpendicular axes. Two elongated adjustment arms are pivotally connected to extension arms which telescope into opposite ends of a hollow connecting tube. The support positions along and about the three axes is achieved by pivoting the arms and the connected relationships of a back shell and cushion to the connecting tube, while the adjustment arms remain pivotally connected to the wheelchair and the extension arms are telescopically retained in the connecting tube.

대표청구항 ▼

1. A back support assembly for connection to transversely spaced apart canes of a wheelchair by which to support a back shell and back cushion against which a back and upper torso of a user of the wheelchair is positioned, comprising: a pair of mounting devices, each mounting device adapted for conn

1. A back support assembly for connection to transversely spaced apart canes of a wheelchair by which to support a back shell and back cushion against which a back and upper torso of a user of the wheelchair is positioned, comprising: a pair of mounting devices, each mounting device adapted for connection to a cane of the wheelchair;a pair of adjustment arms each having first and second opposite ends, the first ends of the adjustment arms connected respectively to the mounting devices to pivot with respect to the mounting devices;a pair of extension arms each having first and second opposite ends, the first ends of the extension arms connected respectively to the second ends of the adjustment arms to selectively pivot the extension arms relative to the adjustment arms and to rigidly maintain a selective pivot position of each extension arm relative to the connected adjustment arm, the second end of each extension arm having a predetermined cross-sectional configuration;a connecting structure having opposite hollow ends with openings into which the second ends of the extension arms are respectively inserted to telescope relative to the connecting structure, the opening having a complementary predetermined cross-sectional configuration corresponding to the predetermined cross-sectional configuration of the second end of each extension arm which is inserted into that opening;a back retaining clamp connected to the connecting structure to pivot selectively about the connecting structure; anda back shell connector connected to the back retaining clamp to move selectively vertically relative to the connecting structure, the back shell connector also adapted to connect to the back shell in a selected rotational position relative to the connecting structure. 2. A back support assembly as defined in claim 1, wherein: the connection of the first ends of the adjustment arms to the mounting devices maintains the adjustment arms freely pivotal relative to the mounting devices. 3. A back support assembly as defined in claim 1, wherein: each mounting device comprises a receiver block having a receiver opening formed therein;the first end of the adjustment arm includes a bushing extending therefrom into the receiver opening;a fastener extends between the first end of the adjustment arm and the receiver block to maintain the bushing within the receiver opening; andthe bushing transfers substantially all torsional force between the adjustment arm and the mounting block independently of the fastener. 4. A back support assembly as defined in claim 3, wherein: the bushing includes a conically-shaped tapered portion which extends away from the first end of the adjustment arm; andthe receiver opening includes a conically-shaped portion which is complementary to the tapered portion of the bushing and which receives therein the tapered portion of the bushing. 5. A back support assembly as defined in claim 3, wherein: the fastener comprises a quick release pin which is rigidly connected to the first end of the adjustment arm. 6. A back support assembly as defined in claim 1, wherein: the connection of the first end of each extension arm to the second end of each adjustment arm comprises a bushing extending from one of the first end of the extension arm or the second end of the adjustment arm, and an annular recess formed in the other one of the first end of the extension arm or the second end of the adjustment arm, the annular recess receiving the bushing therein; anda fastener extending between the second end of the adjustment arm and the first end of the extension arm to apply fastening force to draw the second end of the adjustment arm and the first end of the extension arm into contact with one another to rigidly maintain the selective relative pivoted position of the extension arm and the connected adjustment arm; andthe bushing transferring torsional force between the adjustment arm and the extension arm. 7. A back support assembly as defined in claim 6, wherein: the first end of each extension arm and the second end of each adjustment arm each include complementary mating areas which contact each other to maintain the selective relative pivoted position of the extension arm and the connected adjustment arm, the mating areas each include complementary structures which fit and engage together to prevent the relative rotation and maintain the selective relative pivoted position. 8. A back support assembly as defined in claim 7, wherein: each complementary mating area is annularly shaped;one annular shaped mating area circumscribes the bushing extending from the one of the first end of the extension arm or the second end of the adjustment arm;the other annular shaped mating area circumscribes the annular recess formed in the other one of the first end of the extension arm or the second end of the adjustment arm; andthe fastener comprises a bolt which extends between the second end of the adjustment arm and the first end of the extension arm at a position which is coaxial with the bushing and the annular recess and the mating areas, the bolt applying selective fasting force for holding the complementary mating areas in engagement with one another. 9. A back support assembly as defined in claim 8, wherein: the connection of the first end of each extension arm to the second end of each adjustment arm further comprises a spring positioned to apply separation force in opposition to the fastening force from the fastener, the separation force from the spring separating the mating areas of first end of each extension arm and the second end of each adjustment arm from engagement with one another upon relieving the fastening force from the bolt. 10. A back support assembly as defined in claim 9, wherein: the separation of the complementary structures of the mating areas is sufficient to disengage the complementary structures and allow for relative pivoting movement of the extension arm relative to the adjustment arm while the bushing remains in the annular recess. 11. A back support assembly defined in claim 10, wherein: the complementary structures of the complementary mating areas which engage to prevent relative rotation and maintain the selective relative pivoted position comprise radially extending teeth and grooves. 12. A back support assembly as defined in claim 1, wherein: a fastener extends between the second end of the adjustment arm and the first end of the extension arm to apply fastening force to draw the second end of the adjustment arm and the first end of the extension arm into engagement with one another; andthe connection of the first end of each extension arm to the second end of each adjustment arm comprises complementary mating areas formed on the first end of the extension arm and on the second end of the adjustment arm, the complementary mating areas each include complementary structures which engage and fit together to prevent the relative rotation and maintain the selective relative pivoted position of the extension arm and the adjustment arm upon the fastener drawing the complementary structures of second end of the adjustment arm into engagement with the complementary structures of the first end of the extension arm. 13. A back support assembly as defined in claim 12, wherein: the connection of the first end of each extension arm to the second end of each adjustment arm further comprises a spring positioned to apply separation force in opposition to the fastening force from the fastener, the separation force from the spring separating the mating area of first end of the extension arm from the mating area of the second end of the adjustment arm upon relieving the fastening force from the fastener, the separation of the mating areas permitting relative pivoting movement of the extension arm relative to the adjustment arm while the fastener remains connected between the first end of the extension arm and the second end of the adjustment arm. 14. A back support assembly as defined in claim 1, wherein: the connecting structure is defined by a connecting tube;the complementary predetermined cross-sectional configurations of the opening in the connecting tube and the second end of each extension arm each include a flat surface which adjoins a flat surface of the other complementary cross-sectional configuration, the adjoining flat surfaces preventing relative rotation of the connecting tube relative to the second ends of the extension arms. 15. A back support assembly as defined in claim 14, wherein: the second end of each extension arm includes a fastener operative to extend therethrough and contact the complementary cross-sectional configuration of the connecting tube to apply contact force to fix the relative positions of the second end of the extension arm in the connecting tube and prevent relative telescoping movement of the second end of the extension arm and the connecting tube. 16. A back support assembly as defined in claim 15, wherein: the connecting tube defines a slot which extends parallel to the second end of the extension arm and which receives the fastener therein, the fastener preventing relative separation of the second end of the extension arm from the connecting tube when the contact force from the fastener is relieved to permit relative telescoping movement of the second end of the extension arm and the connecting tube. 17. A back support assembly as defined in claim 1, wherein: one of the second end of the extension arm or the connecting structure includes a retainer which extends between the extension arm and the connecting structure to prevent separation of the second end of the extension arm from the connecting structure during relative telescoping movement of the second end of the extension arm and the connecting structure. 18. A back support assembly as defined in claim 1, wherein: the connecting structure is defined by a connecting tube;the complementary predetermined cross-sectional configurations of the opening in the connecting tube and the second end of each extension arm prevent rotation of the connecting tube relative to the second ends of the extension arms; andthe back retaining clamp comprises a structural block and a cap connected to the structural block to collectively define an opening into which the connecting tube is received, the cap is selectively connectable in position to the structural block to apply to a constriction force on the connecting structure at the opening to retain the back retaining clamp at a desired pivoted position relative to the connecting tube. 19. A back support assembly as defined in claim 18, wherein: the back retaining clamp includes a T-shaped bar portion;the back shell connector includes a C-shaped channel portion; andthe T-shaped bar portion is located within the C-shaped channel portion and is movable therealong to achieve relative longitudinal movement of the back shell connector relative to the back retaining clamp along the extension of the T-shaped bar portion and the C-shaped channel portion. 20. A back support assembly as defined in claim 19, wherein: a fastener is operative to apply retaining force between the T-shaped bar portion and the C-shaped channel portion to prevent relative longitudinal movement of the back shell connector relative to the back retaining clamp. 21. A back support assembly as defined in claim 1, wherein: the back shell connector includes a plate and a longitudinal connection portion which movably connects to the back retaining clamp to move the back shell connector along the longitudinal connection portion. 22. A back support assembly as defined in claim 1, wherein: the back shell connector includes a plate adapted to be connected to the back shell, the plate including annular slots formed therein to receive fasteners extending between the plate and the back shell, the annular slots permitting attachment of the back shell to the back shell connector in a selectively pivoted position. 23. A back support assembly as defined in claim 1, wherein: each mounting device comprises a receiver block and a clamp;the clamp includes a retention bracket connected to the receiver block and an attachment bracket pivotally connected to the retention bracket to pivot the attachment bracket relative to the retention bracket, the attachment bracket and the retention bracket defining an opening between the attachment bracket and the retention bracket within which to receive the cane; andthe clamp further including a fastener extending between the attachment bracket and the retention bracket to force the attachment bracket toward the retention bracket and to constrict the opening around the cane, the fastener remaining connected to one of the attachment bracket or the retention bracket and selectively detaching from the other one of the attachment bracket or the retention bracket. 24. A back support assembly as defined in claim 23, wherein: the fastener comprises an elongated bolt having threads at one end and a head at another end;the clamp further includes a barrel nut into which the bolt is threadably connected at the one of the attachment bracket or the retention bracket; andthe other one of the attachment bracket or the retention bracket includes a slot into which the head of the bolt is selectively positioned when the attachment bracket is forced toward the retention bracket and from which the head of the bolt is selectively removed to selectively detach the bolt from the other one of the attachment bracket or the retention bracket. 25. A method of supporting a back and upper torso of a wheelchair user along and about three mutually perpendicular longitudinal, transverse and vertical axes by a back cushion connected to a back shell connected to a wheelchair having a frame, comprising: operatively and pivotally connecting first ends of two elongated adjustment arms on respectively opposite transverse sides of the wheelchair frame;pivotally connecting first ends of elongated extension arms to second ends of the adjustment arms;telescopically extending second ends of the extension arms into opposite ends of a connecting structure;operatively attaching the back shell to the connecting structure;adjusting the longitudinal position of the back cushion along the longitudinal axis and adjusting the pivotal position of the back cushion about the vertical axis by selectively establishing and fixing pivoted positions of the adjustment and extension arms relative to one another;adjusting the transverse position of the back cushion along the transverse axis by one of telescopically moving the connecting structure relative to the second ends of the extension arms or by positioning the back shell at a selected transverse position along the connecting structure;adjusting the pivoted position of the back cushion about the transverse axis by selectively pivoting the back shell about the transverse axis relative to the connecting structure at the operative attachment of the back shell to the connecting structure;adjusting the vertical position of the back cushion along the vertical axis by selectively positioning the back shell at a selected position along the vertical axis relative to the connecting structure at the operative attachment of the back shell to the connecting structure;adjusting the pivoted position of the back cushion about the longitudinal axis by selectively pivoting the position the back shell about the longitudinal axis at the operative attachment of the back shell to the connecting structure; andperforming all of the aforesaid adjustments while the first ends of the adjustment arms remain operatively pivotally connected to the canes and while the second ends of the extension arms are retained in the connecting structure. 26. A method as defined in claim 25, further comprising: maintaining the pivoted positions of the extension arms and the connected adjustment arms by contacting the second ends of the adjustment arms and the first ends of the extension arms with one another. 27. A method as defined in claim 25, further comprising: maintaining the pivoted positions of the extension arms and the adjustment arms by contacting complementary mating structures which fit and engage together on the first ends of the extension arms and on the second ends of the adjustment arms. 28. A method as defined in claim 27, further comprising: contacting the complementary mating structures on the second ends of the adjustment arms and the first ends of the extension arms by applying fastening force between the second ends of the adjustment arms and the first ends of the extension arms with a fastener. 29. A method as defined in claim 28, further comprising: transferring torsional force between the adjustment arms and the extension arms through bushings which extend between the first ends of the extension arms and the second ends of the adjustment arms. 30. A method as defined in claim 28, further comprising: applying separation force between the first ends of the extension arms and the second ends of the adjustment arms in opposition to the fastening force from the fastener to separate the complementary mating structures of first ends of the extension arms and the second ends of the adjustment arms from engagement with one another upon relieving the fastening force from the fastener. 31. A method as defined in claim 27, further comprising: separating the complementary mating structures sufficiently to disengage the complementary structures to allow adjusting the pivoted positions of the extension arms and the adjustment arms. 32. A method as defined in claim 25, further comprising: preventing relative rotation of the connecting structure relative to the second ends of the extension arms by engaging an opening of predetermined cross-sectional configuration in the connecting structure with a complementary cross-sectional configuration of the second end of each extension arm. 33. A method as defined in claim 25, further comprising: preventing relative telescoping movement of the second ends of the extension arms and the connecting structure by selectively applying contact force between the second ends of the extension arms and the connecting structure to fix the relative positions of the second ends of the extension arms in the connecting structure. 34. A method as defined in claim 25, further comprising: preventing separation of the second ends of the extension arms from the connecting structure during relative telescoping movement of the second ends of the extension arms and the connecting structure. 35. A method as defined in claim 25, further comprising: retaining the back shell to the connecting structure with a back shell connector; andorienting the back shell connector at a desired pivoted position relative to the connecting structure by applying a constriction force on the connecting structure from the back shell connector. 36. A method as defined in claim 25, further comprising: selectively pivoting the position of the back shell about the longitudinal axis by attaching a back shell connector to the back shell in the selectively pivoted position. 37. A method as defined in claim 25, further comprising: maintaining a freely pivotal connection of the first ends of the adjustment arms to the opposite sides of the wheelchair frame; andpreventing relative pivoting movement of the adjustment arms relative to the wheelchair frame by maintaining the pivoted positions of the extension arms relative to the adjustment arms.