To improve a supporting function regarding a treatment chair or a head supporting body.
This medical or dental treatment chair is provided with a backrest (4) and the head supporting body (7). The head supporting body (7) is pivotally connected to the backrest (4) by a joint device (17) provided with a first joint (24) and can be fixed at respective pivoting positions by a fixing device (19a). In order to improve the supporting function, the fixing device (19a) is provided with a piston cylinder (34a) provided with two action chambers (36 and 37), the piston cylinder is connected to the joint part of the first joint (24), the action chambers (36 and 37) are connected to each other by a connection pipe (38) where a selectively openable/closable valve (39) is arranged and an operation member (45) for selectively opening and closing the valve (39) is provided.
BANK REINHOLD VON
RAPP KARLHEINZ
JPS58169448A | 1983-10-05 | |||
JPS62240054A | 1987-10-20 | |||
JPS6431732U | 1989-02-27 | |||
JPH07313562A | 1995-12-05 |