WHEELCHAIR ANTI-TIP APPARATUS

• US 3,848,883 A
• Filed: 08/08/1973
• Issued: 11/19/1974
• Est. Priority Date: 08/08/1973
• Status: Expired due to Term

• Current Assignee: Stephen J. Breacain
• Original Assignee: Stephen J. Breacain
• Inventors: Breacain, Stephen J.
• Primary Examiner(s): Wood, Jr., M. Henson
• Assistant Examiner(s): Mar, Michael
• Application Number:
  US05/386,736
• Time in Patent Office: 468 Days
• Field of Search: 280/5.2,5.32,242R,242WC,211,282,293 297/DIG.10
• US Class Current: 280/5.32
• CPC Class Codes: A61G 5/06 with obstacle mounting facilities, e.g. for climbing stairs, kerbs or steps
• CPC Class Codes: A61G 5/08 foldable
• CPC Class Codes: A61G 5/0825 comprising a scissor-type frame, e.g. having pivoting cross bars for enabling folding
• CPC Class Codes: A61G 5/1089 Anti-tip devices

Abstract

An anti-tip apparatus for a wheelchair includes a main tube extending laterally and rearwardly from the rear frame upright of a wheelchair, and an extension tube slidably received in each main tube and spring-biased to a retracted position. The extended ends of the extension tubes are joined by a transverse support tube to provide rigidity and strength to the apparatus. A wheel or coaster at the end of each extension tube allows the chair to roll rather than capsize over the tube ends, and reduces the shock to the chair. A manually releasable spring detent latch on each main tube holds the apparatus in the extended position, allowing the wheelchair occupant safely to tip the chair back onto the extended wheels to negotiate steps and curbs, and to retract the apparatus when manuvering in close quarters. The transverse support tube is manually collapsible, permitting the wheelchair to be folded for storage or transportation.

Claims

1. In combination with a wheelchair having main rear wheels, an anti-tip apparatus comprising:

horizontal member means secured to the frame of sAid wheelchair adjacent the axes of rotation of said wheels and extending laterally and rearwardly of said wheels of said wheelchair in normally parallel relation to a ground surface; and

extension member means slidably secured to said horizontal member means and extensible to a position rearwardly of said wheels for preventing excessive rearward tipping of said wheelchair.

2. The anti-tip apparatus of claim 1, wherein said horizontal member means includes a main tube secured to a rear frame member of said wheelchair.

3. The anti-tip apparatus of claim 2, wherein said extension member means includes an extension tube slidably received within said main tube.

4. The anti-tip apparatus of claim 3, further including a rod secured to said main tube and disposed axially therein, said rod being slidably received in an opening in one end of said extension tube.

5. The anti-tip apparatus of claim 3, further including latch means for locking said extension tube in one or more positions within the main tube.

6. The anti-tip apparatus of claim 5, said latch means including a detent extending into an opening in the wall of said main tube and registering with and engaging one of a plurality of apertures in the wall of said extension tube.

7. The anti-tip apparatus of claim 6, further including resilient means for biasing said detent into engagement with one of said plurality of apertures, and manual means for disengaging said detent from said one of said plurality of apertures.

8. The anti-tip apparatus of claim 1, further including bracket means for securing said horizontal member means to a frame member of said wheelchair adjacent and above the axes of said wheels.

9. The anti-tip apparatus of claim 1, said bracket means comprising a clevis bracket secured to said horizontal member means, said clevis bracket including two parallel and spaced apart tines for receiving said frame member securely therebetween.

10. The anti-tip apparatus of claim 3, said wheelchair including a left rear frame member and a right rear frame member, and parallel left and right main tubes secured respectively to each of said rear frame members, each main tube receiving an extension tube therein.

11. The anti-tip apparatus of claim 10, further including a collapsible support assembly transverse to and joining said extension tubes.

12. The anti-tip apparatus of claim 11, wherein said support assembly includes left and right support members and a medial member, each support member hinged at one end to said medial member, the other ends of said support members secured to the respective left and right extension tubes.

13. The anti-tip apparatus of claim 12, further including a slide tube slidably received about said support assembly, said slide tube immobilizing said hinges of said medial member when disposed about said medial member.

14. The anti-tip apparatus of claim 13, further including retaining means for retaining said slide tube in a non-interfering disposition with said hinges of said medial member.

15. The anti-tip apparatus of claim 11, wherein said collapsible support tube assembly is manually adjustable in length to accommodate wheelchairs of differing widths.