초록 ▼

A wheelchair base including a base frame and a pair of pivot arm assemblies each including a first pivot arm and a second pivot arm, pivotally coupled to each other for pivotal movement about a transverse pivot axis. The pivot arms defining first and second auxiliary wheel attachments opposed to the

A wheelchair base including a base frame and a pair of pivot arm assemblies each including a first pivot arm and a second pivot arm, pivotally coupled to each other for pivotal movement about a transverse pivot axis. The pivot arms defining first and second auxiliary wheel attachments opposed to the transverse pivot axis for attaching first and second end auxiliary wheels. Each pivot arm assembly including a link pivotally coupled to the second pivot arm intermediate the transverse pivot axis and the second auxiliary wheel attachment for pivotal movement about a link axis substantially parallel to the transverse pivot axis forming a drive wheel attachment intermediate the auxiliary wheel attachments. The pivot arm assemblies are mounted to the base frame substantially laterally opposed to each other through the link and first pivot arm such that the pivot arm assemblies are independently pivotable relative to the base frame.

대표청구항 ▼

1. A wheelchair base, said wheelchair base being usable with first and second drive wheels, first end first and second auxiliary wheels and second end first and second auxiliary wheels, said wheelchair base comprising: a base frame; a first pivot arm assembly, said first pivot arm assembly including

1. A wheelchair base, said wheelchair base being usable with first and second drive wheels, first end first and second auxiliary wheels and second end first and second auxiliary wheels, said wheelchair base comprising: a base frame; a first pivot arm assembly, said first pivot arm assembly including a first assembly first pivot arm and a first assembly second pivot arm, said first assembly first and second pivot arms being pivotally coupled to each other for pivotal movement about a first assembly transverse pivot axis, said first assembly first and second pivot arms defining respectively first assembly first and second auxiliary wheel attachments substantially opposed to said first assembly transverse pivot axis for attaching respectively said first and second end first auxiliary wheels thereto, said first pivot arm assembly further including a first assembly link pivotally coupled to said first assembly second pivot arm at a location intermediate said first assembly transverse pivot axis and said first assembly second auxiliary wheel attachment for pivotal movement about a first assembly link axis substantially parallel to said first assembly transverse pivot axis, said first pivot arm assembly further defining a first drive wheel attachment at a location intermediate said first assembly first and second auxiliary wheel attachments for attaching said first drive wheel thereto; and a second pivot arm assembly, said second pivot arm assembly including a second assembly first pivot arm and a second assembly second pivot arm, said second assembly first and second pivot arms being pivotally coupled to each other for pivotal movement about a second assembly transverse pivot axis, said second assembly first and second pivot arms defining respectively second assembly first and second auxiliary wheel attachments substantially opposed to said second assembly transverse pivot axis for attaching respectively said first and second end second auxiliary wheels thereto, said second pivot arm assembly further including a second assembly link pivotally coupled to said second assembly second pivot arm at a location intermediate said second assembly transverse pivot axis and said second assembly second auxiliary wheel attachment for pivotal movement about a second assembly link axis substantially parallel to said second assembly transverse pivot axis, said second pivot arm assembly further defining a second drive wheel attachment at a location intermediate said second assembly first and second auxiliary wheel attachments for attaching said second drive wheel thereto; said first and second pivot arm assemblies being mounted to said base frame substantially laterally opposed to each other with said first and second assembly transverse pivot axes substantially parallel to each other; said first and second assembly first pivot arms pivotally coupled to said base frame for pivotal movement respectively about a first and a second assembly first arm axis, said first and second assembly first arm axes being substantially parallel to said first assembly transverse pivot axis; and said first and second assembly links pivotally coupled to said base frame for pivotal movement respectively about a first and a second assembly link-to-frame axis, said first and second assembly link-to-frame axes being substantially parallel to said first assembly transverse pivot axis; said first pivot arm assembly being pivotable relative to said base frame independently of said second pivot arm assembly. 2. A wheelchair base as defined in claim 1, wherein said first assembly link defines a first assembly link length, said first assembly link including a suspension element for allowing variations in said first assembly link length. 3. A wheelchair base as defined in claim 2, wherein said suspension element is configured for biasing said first assembly link towards an equilibrium length. 4. A wheelchair base as defined in claim 2, wherein said suspension element includes a McPherson suspension strut. 5. A wheelchair base as defined in claim 1, wherein said first pivot arm assembly further includes a first assembly reinforcing element operatively coupled to said first assembly second pivot arm and to said base frame for allowing pivotal movements of said first assembly link relative to said first assembly second pivot arm and said base frame. 6. A wheelchair base as defined in claim 5, wherein said first assembly reinforcing element includes a reinforcing element first member pivotally coupled to said base frame; and a reinforcing element second member pivotally coupled to said first assembly second pivot arm and to said reinforcing element first member. 7. A wheelchair base as defined in claim 6, wherein said first assembly reinforcing element and said first assembly link are pivotally coupled to said base frame in a spaced apart relationship relative to each other and said first assembly reinforcing element and said first assembly link are pivotally coupled to said first assembly second pivot arm in a spaced apart relationship relative to each other. 8. A wheelchair base as defined in claim 1, said wheelchair base being usable with a seat assembly mounted to said base frame by an intended user sitting on said seat assembly, said wheelchair base defining a base front end and a base rear end, said first assembly second pivot arm being located rearwardly relative to said first assembly first pivot arm. 9. A wheelchair base as defined in claim 1, further comprising a power drive assembly operatively coupled to said first drive wheel attachment for rotating said first drive wheel relative to said base frame. 10. A wheelchair base as defined in claim 9, wherein said power drive assembly includes a drive motor longitudinally coupled to a gearbox unit, said gear box unit being coupled to said first drive wheel attachment for rotating said first drive wheel relative to said base. 11. A wheelchair base as defined in claim 10, wherein said drive motor is attached to said first assembly first pivot arm. 12. A wheelchair base as defined in claim 10, wherein said drive motor is attached to said first assembly second pivot arm. 13. A wheelchair, said wheelchair comprising: a base frame; a first pivot arm assembly, said first pivot arm assembly including a first assembly first pivot arm and a first assembly second pivot arm, said first assembly first and second pivot arms being pivotally coupled to each other for pivotal movement about a first assembly transverse pivot axis; first and second end first auxiliary wheels mounted respectively to said first assembly first and second pivot arms substantially opposed to said first assembly transverse pivot axis, said first pivot arm assembly further including a first assembly link pivotally coupled to said first assembly second pivot arm at a location intermediate said first assembly transverse pivot axis and said second end first auxiliary wheel for pivotal movement about a first assembly link axis substantially parallel to said first assembly transverse pivot axis; a first drive wheel mounted to said first pivot arm assembly at a location intermediate said first and second end first auxiliary wheels; a second pivot arm assembly, said second pivot arm assembly including a second assembly first pivot arm and a second assembly second pivot arm, said second assembly first and second pivot arms being pivotally coupled to each other for pivotal movement about a second assembly transverse pivot axis; first and second end second auxiliary wheels mounted respectively to said second assembly first and second pivot arms substantially opposed to said second assembly transverse pivot axis, said second pivot arm assembly further including a second assembly link pivotally coupled to said second assembly second pivot arm at a location intermediate said second assembly transverse pivot axis and said second end second auxiliary wheel for pivotal movement about a second assembly link axis substantially parallel to said second assembly transverse pivot axis; and a second drive wheel mounted to said second pivot arm assembly at a location intermediate said first and second end second auxiliary wheels; said first and second pivot arm assemblies being mounted to said base frame substantially laterally opposed to each other with said first and second assembly transverse pivot axes substantially parallel to each other; said first and second assembly first pivot arms pivotally coupled to said frame for pivotal movement respectively about a first and a second assembly first arm axis, said first and second assembly first arm axes being substantially parallel to said first assembly transverse pivot axis; and said first and second assembly links pivotally coupled to said frame for pivotal movement respectively about a first and a second assembly link-to-frame axis, said first and second assembly link-to-frame axes being substantially parallel to said first assembly transverse pivot axis; said first pivot arm assembly being pivotable relative to said base frame independently of said second pivot arm assembly. 14. A wheelchair as defined in claim 13, further comprising a seat assembly mounted to said base frame. 15. A wheelchair as defined in claim 14, further comprising a power drive assembly operatively coupled to said first pivot arm assembly and to said first drive wheel for rotating said first drive wheel relative to said base frame to propel said wheelchair. 16. A wheelchair as defined in claim 14, further comprising a pair of power drive assemblies each operatively coupled to a respective one of said first and second pivot arm assemblies and to a respective one of said first and second drive wheels for rotating respectively said first and second drive wheels relative to said base frame to propel said wheelchair.