Friction resistance hinge with auto-lock

[0007]The invention provides a hinge to be coupled between first and second members, and to resistively hold an orientation between the first and second members at a plurality of orientations, and/or to bias the first and second members in a predetermined set orientation. The hinge comprises an elongated shaft having a proximal end and a distal end. A head is disposed on the distal end of the shaft, and has a cross-sectional shape to mate with a shape of a bore in the first member, such that the shaft rotates with the first member with respect to the second member. An axel portion on the shaft has a cross-sectional shape that is non-circular. A key is rotatably disposed on the axel portion of the shaft. The key has a key ring rotatably disposed on the axel portion of the shaft, and a tab extending from the key ring. The tab has a profile to mate with a shape of a slot in the second member, such that the key rotates with the second member with respect to the first member. A friction ring is disposed on the axel portion of the shaft proximal the key, and rotatable with the shaft and with respect to the key. The friction ring has a bore with a shape that mates with the cross-sectional shape of the axel portion of the shaft. The key is held in position with respect to the axel portion, and thus the second member is held in position with respect to the first member, by friction between the key and the friction ring. A spring is carried by the shaft and biases the key and the friction ring together. A fastener is disposed on the shaft with the spring between the fastener and the key and the friction ring.

[0008]In a more detailed aspect of the invention, the hinge can further comprise, or the friction ring can be a detent ring comprising, a dimple formed in the key ring of the key or the friction ring, and a detent extending axially from another of the key ring or the friction ring and removably received within the dimple. The spring biases the detent into engagement with the dimple. The key rotates on the shaft between a plurality of different orientations, including at least: 1) a predetermined set orientation in which the detent is disposed in the dimple, defining an autolock orientation, and in which a greater amount of force is required to rotated the key out of the predetermined set orientation; and 2) a friction hold orientation, different than the predetermined set orientation, in which the detent is disposed out of the dimple, and in which the key is held with respect to the shaft by friction between the key and the friction ring, and in which a lesser amount

Such hinges can be subject to force and