Abstract: A ratchet gear is provided to each of a pair of arms (rotors), which are coupled through a bolt, at counter surfaces of a pair of their respective rotary portions opposing in an axial direction of the bolt serving as an axis of relative rotation, and each ratchet gear is provided with a plurality of gear teeth, while both the arms are pushed in their opposing direction by a spring, so that a relative rotating position of the arms is adjusted step by step per an angle set in accordance with the gear teeth, whereby it is possible to provide a rigid angle adjusting device that can be assembled at a low cost without increasing the size.

Abstract: The invention provides a telescopic member having an inner cylinder slidably fitted into an outer cylinder in the axial direction and a lock mechanism, placed between the cylinders, for holding relative movements therebetween. A holder is secured to the outer cylinder and allows its inner circumferential surface to slide on the outer circumferential surface of the inner cylinder so that a frictional force is applied to the relative movements between the cylinders. The holder has a braking chamber on the side facing the inner cylinder to contain a friction body that rolls on the circumferential surface of the inner cylinder. The braking chamber has a taper surface so as to have a space that becomes narrower in the push-in direction of the inner cylinder, and first and second moving end surfaces that are separated with a predetermined distance in the push-in direction so as to intersect the taper surface, and is formed into a reversed trapezoidal shape in its cross-section viewed at one side.