Patent ID: 8052352

Claim:
A yieldable prop comprising: a) at least one conduit having a first end and an opposite second end, and a hollow portion extending from the first end toward the second end, and b) a bearing plate assembly comprising: 1) a support member; 2) a threaded shaft having a first end and an opposite second end with the first end of the threaded shaft mounted to the support member, and 3) a body having a first side and an opposite second side with the first side of the body supported on the first end of the at least one conduit, the body being rotatable relative to the at least one conduit, the body having a threaded passageway to receive the threaded shaft with the second end of the threaded shaft in the first end of the at least one hollow conduit, wherein rotating the body in a first direction moves the support member to increase spaced distance between the support member and the first side of the body, and rotating the body in a second opposite direction moves the support member to decrease the spaced distance between the support member and the first side of the body, wherein the at least one conduit is a first conduit, and further comprising a hollow second conduit, the second conduit having a first end and an opposite second end with the first conduit slideably received in the first end of the second conduit, and a clamp assembly acting on outer surface portions of the first and second conduits, wherein the clamp assembly in an engaging position provides resistance to the first conduit moving into the second conduit, and the clamp assembly in the non-engaging position eliminates the resistance to the first conduit moving into the second conduit.