Patent ID: 6863293

Claim:
A wheelchair comprising: a seat, a pair of rear wheels fixed to axle shafts arranged below the seat and arranged outside both sides of the seat, a grasping portion arranged rearwardly of the seat to be grasped and operated by a helper, at least one front wheel arranged forwardly of the axle shafts, actuation plates arranged on a back surface of the seat and in juxtaposition with the seat to descend when a user sits on the seat to lower the seat with a weight of the user and to ascend when the user rises from the seat to permit the seat to return with removal of the weight, a first bias means provided on the actuation plates wherein the actuation plates are constantly biased upward by the first bias means; brake means mounted on the axle shafts to brake the axle shafts and energized constantly in a non-braking direction, and levers coupled directly or indirectly to the brake means to move according to descending motions of the actuation plates to act on the brake means to put the brake means in a non-braking state and to move according to ascending motions of the actuation plates to act on the brake means to put the brake means in a braking state, the levers also being connected to the actuation plates through lengths of wire wherein the levers are pulled upwards by the lengths of wire with upward movements of the actuation plates and the levers move downwards with downward movements of the actuation plates, wherein when the user sits on the seat, the user's weight causes the seat to descend and the actuation plates to move downward and positional movements of the actuation plates cause the levers to move to release braking on the axle shafts by the brake means, and when the user having sat on the seat rises, the actuation plates having been pushed down by the user's weight move upward and positional movements of the actuation plates cause the levers to move to permit the brake means to brake the axle shafts.