Suspension for wheeled vehicles

• US 10,512,572 B2
• Filed: 03/26/2018
• Issued: 12/24/2019
• Est. Priority Date: 10/25/2002
• Status: Expired due to Term

• Current Assignee: Invacare Corporation
• Original Assignee: Invacare Corporation
• Inventors: Goertzen, Gerold, Null, William A., Cuson, Robert L.
• Primary Examiner(s): Frisby, Keith J
• Application Number:
  US15/935,538
• Publication Number:
  US 20180221225A1
• Time in Patent Office: 638 Days
• Field of Search: 180907, 280755, 2802501, 2803041
• CPC Class Codes: A61G 2203/14 Joysticks
• CPC Class Codes: A61G 2203/32 for force
• 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 5/10 Parts, details or accessories
• CPC Class Codes: A61G 5/101 of the parking brake type, e.g. holding the wheelchair
• CPC Class Codes: A61G 5/1032 engaging an element of the drive or transmission, e.g. drive belt, electrodynamic brake
• 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: B60G 15/08 having fluid spring
• CPC Class Codes: B60G 17/005 Suspension locking arrangements for retractable wheels B62D61/12
• CPC Class Codes: B60G 17/0152 characterised by the action on a particular type of suspension unit B60G17/01941 takes precedence
• CPC Class Codes: B60G 17/016 characterised by their responsiveness, when the vehicle is travelling, to specific motion, a specific condition, or driver input B60G17/017 takes precedence
• CPC Class Codes: B60G 17/048 with the regulating means inside the fluid springs B60G17/044 takes precedence
• CPC Class Codes: B60G 17/056 Regulating distributors or valves for hydropneumatic systemsB60G17/044 - B60G17/048, B60G17/0416 take precedence; Fluid interconnection systems to control vehicle inclination B60G21/06, B60G21/10; valves per se F16K
• CPC Class Codes: B60G 17/08 Characteristics of fluid dampers adjusting fluid dampers in general F16F9/44 - F16F9/53
• CPC Class Codes: B60G 2204/4604 mechanically, e.g. using a hook as anticreep mechanism
• CPC Class Codes: B60G 2204/4605 hydraulically, e.g. interrupting communication between the chambers of a hydraulic cylinder
• CPC Class Codes: B60G 2300/24 Wheelchairs
• CPC Class Codes: B60G 2400/05 Attitude
• CPC Class Codes: B60G 2500/10 : Damping action or damper
• CPC Class Codes: B60G 7/005 : Ball joints B60G7/006 takes precedence; for steering linkage B62D7/16; ball joints per se F16C11/06
• CPC Class Codes: B60Y 2200/84 : Wheelchairs
• CPC Class Codes: F16F 9/535 : Magnetorheological [MR] fluid dampers springs comprising magnetorheological [MR] elastomers F16F1/361
• CPC Class Codes: Y10S 180/907 : Motorized wheelchairs
• CPC Class Codes: Y10S 297/04 : Wheelchair

Abstract

A wheelchair suspension comprises a frame, at least one pivot arm, at least one front caster, at least one rear caster, a stabilizing system, and a sensor. The pivot arm is coupled to the frame. The front caster is coupled to the pivot arm. The rear caster is coupled to the frame. The stabilizing system is coupled to the frame and the pivot arm. The sensor is arranged such that tipping of the frame causes actuation of the stabilizing system to at least partially resist further movement of the frame.

Claims

1. A wheelchair suspension comprising:

a frame;

a front caster assembly pivotally connected to the frame, the front caster pivot assembly comprising a front caster pivot arm and a front caster;

a rear caster assembly pivotally connected to the frame, the rear caster assembly comprising a rear caster arm and a rear caster; and

a link coupled to the front caster assembly and extending rearward from the front caster assembly toward the rear caster assembly;

wherein downward movement of the rear caster causes the link to lock thereby causing the front caster assembly to lock in a position relative to the frame.

2. The wheelchair suspension of claim 1, wherein the rear caster assembly further comprises a first ratchet, wherein the link is connected to a second ratchet, and wherein engagement between the first ratchet and the second ratchet causes the link to lock.

3. The wheelchair suspension of claim 2, wherein downward movement of the rear caster causes the first ratchet to engage the second ratchet.

4. The wheelchair suspension of claim 2, wherein a spring is disposed between the first ratchet and the rear caster arm.

5. The wheelchair suspension of claim 1, wherein the front caster assembly comprises a four-bar linkage that includes the front caster arm and a second front caster arm, wherein the front caster arm is coupled to the frame at a first pivot axis and the second front caster arm is coupled to the frame at a second pivot axis.

6. A wheelchair comprising:

a frame;

a seat supported by the frame;

a pair of drive wheels supporting the frame;

a front caster assembly pivotally connected to the frame, the front caster assembly comprising a front caster arm and a front caster;

a rear caster assembly pivotally connected to the frame, the rear caster assembly comprising a rear caster arm and a rear caster; and

a link coupled to the front caster assembly and extending rearward from the front caster assembly toward the rear caster assembly;

wherein downward movement of the rear caster causes the link to lock thereby causing the front caster assembly to lock in a position relative to the frame.

7. The wheelchair suspension of claim 6, wherein the rear caster assembly further comprises a first ratchet, wherein the link is connected to a second ratchet, and wherein engagement between the first ratchet and the second ratchet causes the link to lock.

8. The wheelchair suspension of claim 7, wherein downward movement of the rear caster causes the first ratchet to engage the second ratchet.

9. The wheelchair suspension of claim 7, wherein a spring is disposed between the first ratchet and the rear caster arm.

10. The wheelchair suspension of claim 6, wherein the front caster assembly comprises a four-bar linkage that includes the front caster arm and a second front caster arm, wherein the front caster arm is coupled to the frame at a first pivot axis and the second front caster arm is coupled to the frame at a second pivot axis.