Obstacle traversing wheelchair

• US 9,987,177 B2
• Filed: 10/05/2015
• Issued: 06/05/2018
• Est. Priority Date: 10/27/2000
• Status: Expired due to Fees

• Current Assignee: Invacare Corporation
• Original Assignee: Invacare Corporation
• Inventors: Goertzen, Gerold, Null, William A.
• Primary Examiner(s): Walters, John D
• Application Number:
  US14/875,110
• Publication Number:
  US 20160022516A1
• Time in Patent Office: 974 Days
• Field of Search: 180 651
• CPC Class Codes: A61G 5/04 motor-driven A61G5/06 takes precedence; motor-operated rests A61G5/12; for vehicles with handlebars, equipped with three or more wheels B62K5/003, B62K5/023
• CPC Class Codes: A61G 5/043 Mid wheel drive
• CPC Class Codes: A61G 5/06 with obstacle mounting facilities, e.g. for climbing stairs, kerbs or steps
• CPC Class Codes: A61G 5/061 for climbing stairs
• CPC Class Codes: A61G 5/1075 tilting the whole seat backwards tilting forwards for standing-up or sitting-down aids A61G5/14
• CPC Class Codes: A61G 5/1078 with shock absorbers or other suspension arrangements between wheels and frame
• CPC Class Codes: A61G 5/1089 Anti-tip devices
• CPC Class Codes: A61G 5/128 for feet
• CPC Class Codes: B60G 17/02 Spring characteristics , e.g. mechanical springs and mechanical adjusting meansB60G17/005, B60G17/015 take precedence
• CPC Class Codes: B60G 17/033 characterised by regulating means acting on more than one spring
• CPC Class Codes: B60G 2200/13 with longitudinal arms only
• CPC Class Codes: B60G 2202/42 Electric actuator
• CPC Class Codes: B60G 2300/24 Wheelchairs
• CPC Class Codes: B60G 2300/40 Variable track or wheelbase vehicles
• CPC Class Codes: B60G 7/001 Suspension arms, e.g. constructional features B60G7/006 takes precedence
• CPC Class Codes: Y10S 180/907 Motorized wheelchairs

Abstract

A wheelchair suspension is provided. The wheelchair suspension includes a frame, a front caster pivot arm, a drive assembly, and a rear caster. The front caster pivot arm is pivotally connected to the frame. The front caster is coupled to a front end of the front caster pivot arm. The drive assembly is pivotally connected to the front caster pivot arm. The drive assembly comprises a drive wheel and a motor that drives the drive wheel. Torquing of the drive wheel by the motor in a forward direction causes the drive assembly to pivot with respect to the front caster pivot arm such that the drive wheel moves forward toward the front caster and a distance between a support surface and the connection between of the drive assembly and the front caster pivot arm increases.

Claims

1. A wheelchair suspension comprising:

a frame;

a pivoting assembly having at least one front caster pivot arm pivotally coupled to the frame, wherein the front caster pivot arm has a first portion and a second portion;

at least one front caster attached to the second portion of the front caster pivot arm;

a rear caster coupled to the frame; and

a drive assembly having a motor mount and at least one drive wheel in contact with a supporting surface, wherein the motor mount is pivotally connected directly to the at least one front caster pivot arm.

2. The wheelchair suspension of claim 1, wherein the front caster pivot arm further comprises a pivot mounting structure between the first portion and the second portion.

3. The wheelchair suspension of claim 2, wherein the pivot mounting structure comprises at least one bracket and a first sleeve.

4. The wheelchair suspension of claim 3, wherein the at least one bracket is welded to the first portion.

5. The wheelchair suspension of claim 3, wherein the first sleeve is welded to the at least one bracket.

6. The wheelchair suspension of claim 3, wherein a low-friction sleeve is inserted in the first sleeve.

7. A wheelchair suspension comprising:

a frame;

a pivoting assembly having at least one front caster pivot arm pivotally coupled to the frame, wherein the front caster pivot arm has a first portion and a second portion;

at least one front caster attached to the second portion of the front caster pivot arm;

a rear caster coupled to the frame;

a drive assembly having a motor mount and at least one drive wheel in contact with a supporting surface, wherein the motor mount is connected directly to the at least one front caster pivot arm such that the drive assembly is moveable with respect to the front caster pivot arm, and wherein the drive assembly has a motor coupled to the drive wheel; and

a spring connected at opposing ends to the front caster pivot arm and the motor mount, wherein the spring biases the motor in a first direction with respect to the supporting surface.

8. The wheelchair suspension of claim 7, further comprising a coupling plate connected to the front caster pivot arm.

9. The wheelchair suspension of claim 8, wherein the coupling plate interfaces the front caster pivot arm and a front resilient assembly.

10. The wheelchair suspension of claim 8, wherein the coupling plate is affixed to the front caster pivot arm via a rigid tubular connection.

11. The wheelchair suspension of claim 8, wherein the coupling plate has a mounting bracket that receives a pivot pin and interfaces a front resilient assembly.

12. The wheelchair suspension of claim 11, wherein the front caster pivot arm and coupling plate move in unison about the pivot pin.

13. The wheelchair suspension of claim 8, wherein the coupling plate has a mounting bracket that receives a bolt and interfaces a front resilient assembly.