Device for the reciprocal securing of two elongated members telescopically arranged in relation to each other

Claim 1

A releasable locking device for selectively locking two telescopically disposed elongate members to each other, said locking device comprising in combination: an outer tubular member having inner and outer wall surfaces of circular outline; an inner elongate substantially rigid member of circular crosssection disposed within the outer member, the inner diameter of the outer member being larger than the outer diameter of the inner meMber, said inner member being displaceable parallel to the center axis of the outer member; and a releasable locking means including a sleeve rotatably encompassing said outer member, two axially spaced circumferential bearing ridges extending inward from the inner surface of said sleeve to define a cylindrical cavity, the peripheries of said ridges being circular and having an inner diameter substantially equal to the outer diameter of said outer member, whereby said ridges and outer member have the same center axis, the cylindrical cavity having a diameter grater than the diameter of said outer member and a center axis eccentric with reference to the center axis of said outer member so that the inner wall of the cylindrical cavity constitutes a camming surface, said outer member having a slot in its peripheral wall in the region of the cylindrical cavity, and a locking member substantially radially slidable in said slot, said locking member abutting the camming surface and being engageable with the inner member for control of the radial position of the locking member by the angular position of the camming surface, the size of said locking member being such that in one predetermined rotational position of the camming surface relative to the outer surface of the outer member, the locking member releases the inner member from the outer member and in another predetermined rotational position of the camming surface, the locking member is displaced into a position in which it presses the inner member against the outer member, thereby locking the inner member to the outer member.