PROBLEM TO BE SOLVED: To provide a rear wheel anti-rotation device for a wheelchair that safely releases the rear wheel anti-rotation device, eliminates individual adjustment, has a seat plate providing excellent fitting to hip parts, and is inexpensive.SOLUTION: The anti-rotation device includes: a hook 3 that is rotatably supported and rocks between a lock position for locking a spoke 7 by invasion to a rear wheel 110 and a release position for saving from the inner part of the rear wheel a spring member for normally energizing the hook toward the lock position a base 15 arranged under a seat 14 and having a recession 15b to be opened upward a seat plate having a projection that is brought into contact with the lower surface of the seat, energized upward by the spring member, lowered by the body weight of a person when he/she is seated on the seat, and allowed to invade the inner part of the recession of the base when being lowered and a cable 6 fixed to the base and connected to the hook by way of a portion between the recession of the base and the projection of the seat plate. When the seat plate receives the body weight, the projection of the seat plate pushes the cable into the recession of the base. When the cable is pulled, the hook is turned to the release position to release the lock of the spoke.COPYRIGHT: (C)2012,JPO&INPIT【課題】回転止め装置の安全な解除ができ、個別の調整のいらない、尻あたりが良い座板のある、また低コストの車椅子の後輪回転止め装置を提供する。【解決手段】回転可能に支持され、後輪110内に進入してスポーク7を係止する係止位置と後輪内から退避する解除位置との間で遥動するフック3と、フックを係止位置に向けて常時付勢するバネ部材と、座シート14の下方に設置され上方に開く凹部15bを備えたベース15と、座シートの下面に接触しバネ部材により上方に向けて付勢され座シートに着座時の人の体重により下降すると共に下降時にベースの凹部内に進入する凸部を備えた座板と、ベースに固定されベースの凹部と前記座板の凸部との間を経由してフックに連結されたケーブルと6を有し、座板が体重を受けるとその凸部がケーブルをベースの凹部に押し込みケーブルを引っ張ることによりフックがスポークの係止を解除する解除位置に回動する構成とする。【選択図】図2
