Obstacle traversing wheelchair

• US 20050225040A1
• Filed: 06/03/2005
• Published: 10/13/2005
• Est. Priority Date: 10/27/2000
• Status: Active Grant

• Current Assignee: Freedom Designs Inc. (Invacare Corporation), Invacare Corporation, Motion Concepts, L.P (Invacare Corporation)
• Original Assignee: Invacare Corporation
• Inventors: Goertzen, Gerold, Null, William A. Jr.
• Granted Patent: US 7,219,755 B2
• Time in Patent Office: Days
• US Class Current: 280/5.280
• 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

The present invention provides a curb-climbing wheelchair having pivotal arm assemblies. The pivotal arm assemblies include at least one front caster and have the ability to rotate or pivot. The pivot arms rotate or pivot in response to moments generated by accelerating or decelerating the wheelchair thereby raising or lowering the front caster(s) through the rotational movement of the pivot arms. By raising or lowering the front caster(s) in such a manner, curb-like obstacles can be traversed in a low-impact manner.

Claims

1. A wheelchair for traversing obstacles, comprising:

(a) a frame;

(b) a pivoting assembly having at least one pivot arm, said at least one pivot arm comprising

(i) a first portion pivotally coupled to said frame; and

(ii) a second portion having at least one front caster attached thereto for normally contacting a supporting surface of the wheelchair;

(c) a drive assembly coupled to a third portion of said at least one pivot arm;

(d) a rear caster coupled to said frame; and

wherein said at least one pivot arm pivots in response to a moment generated by the drive assembly thereby raising said at least one front caster from said supporting surface to assist said wheelchair in traversing said obstacles.

2. The wheelchair of claim 1 wherein said third portion is in between said first and second portions.

3. The wheelchair of claim 1 further comprising a second pivot arm and a tension bar coupled to the pivot arms for limiting the independent movement of each pivot arm.

4. The wheelchair of claim 1 wherein said pivot assembly further comprises a resilient member coupled to said at least one pivot arm and said frame.

5. A conveyance comprising:

(a) a frame having first and second sides;

(b) a first pivot arm coupled to the first side;

(c) a second pivot arm coupled to the second side;

(d) each pivot arm comprising a portion extending at least partly forward of a most forward portion of the frame; and

(e) a tension bar extending between and coupling the portions of each pivot arm extending at least partly forward of the frame.

6. The conveyance of claim 5 further comprising a drive assembly pivotally coupled to each of the pivot arms.

7. The conveyance of claim 6 further comprising a suspension between each drive assembly and pivot arm.

8. A wheelchair comprising:

(a) a frame means having first and second side members;

(b) a suspension coupled to the frame means;

said suspension comprising;

(i) first and second pivot means respectively coupled to the first and second side members; and

(ii) third and fourth pivot means respectively coupled to the first and second pivot means

(c) first and second drive means respectively coupled to the third and fourth pivot means;

(d) front castor means, for normally contacting a supporting surface of the wheelchair, coupled to the first and second pivot means;

(e) rear castor means coupled to the frame means; and

wherein said first and second pivot means pivot in response to a moment generated by the drive means thereby raising the front caster means from said supporting surface to assist said wheelchair in traversing an obstacle.