摘要 |
A chair control mechanism for supporting both the seat and back rest of a chair, including a seat frame with a control member mounted for limited pivotal movement thereon for supporting the back rest. A torsion spring resiliently urges the control member and back rest in one direction. A back hinge is pivotally mounted on the control member and is adjustable with the aid of a threaded adjustment member and a second torsion spring to provide a positive attitute adjustment for the back rest. A back rest strap is provided carrying the back rest at its upper end and having at its lower end a T-shaped bayonet projection received in an elongated aperture in the back hinge in addition to a threaded fastener so that if for any reason the fastener fails, the back rest will not fall off.
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