Wheelchairs
OwnerRoyal Smith, Edward H. D. Carsoninventors
Life of this patent
Estimating the term…
Abstract
A wheelchair is disclosed which is convertible into a wheeled stretcher, wherein the chair seat will assume a comfortable angle with respect to the horizontal when the chair is in the seating position and will assume a horizontal position coplanar with the back of the chair when the chair is in the stretcher position. The chair seat and back may be locked into any relative position between a fully erect seated position and a fully reclined stretcher position. Leg support members which are connected to the chair may assume any angular position with respect to the horizontal without regard for the relative positions of the seat and back of the chair. The leg support members may have their lengths independently adjusted.
Claims5
A wheelchair convertible into a wheeled stretcher, comprising:
- a pair of wheeled support frame members horizontally spaced from one another, each having a corresponding rearwardly positioned first pivot and a forwardly positioned second pivot at substantially the same elevation;
- a pair of first levers, each having a first length and pivotally mounted on a respective one of said first pivots;
- a chair back support having two lateral sides each proximate to a respective one of said support frame members, each rigidly mounted to the free end of a corresponding one of said first levers;
- a pair of second levers, each having substantially said first length and pivotally mounted on a respective one of said second pivots;
- a pair of front arms, each rigidly mounted at an intermediate point to the free end of a respective one of said second levers;
- a pair of linkages, each having a first end pivotally connected to a respective one of said front arms at a point a second length above said intermediate point and a second end pivotally connected to a corresponding one of said lateral sides of said back support at substantially said second length above said mounting point for the corresponding one of said first levers;
- a pair of extendable chair seat supports, each proximate to a respective one of said support frame members, each comprising a first and second portions which slideably engage one another with the free end of said first portion pivotally connected to a corresponding one of said lateral sides of said back support at a third length below said mounting point for the corresponding one of said first levers and with the free end of said second portion pivotally connected to a corresponding one of said front arms at a fourth length below said intermediate point, said third length being greater than said fourth length;
- whereby a chair seat supported by said pair of extendable seat supports, will assume a comfortable angle with respect to the horizontal when the chair is in a seating position, and will assume a horizontal position coplanar with the back of the chair when the chair is in a stretcher position.
Dependencies are inferred from the claim text.