Abstract: Apparatus for directly converting thermal energy into rotational movement. A long shaft relative to its cross-section and made of an elastic material with a high thermal coefficient of expansion is equipped with a plurality of journals at prescribed points along its axial length. A corresponding number of fixedly mounted circular bearings receive the journals. The bearings are arranged to constrain the shaft into an elastic arc. Thermal energy is applied to all or a substantial part of the concave surface of the arced shaft. Means may be employed to force cool all or a portion of the convex portion of the arced shaft. As a result of this arrangement, the shaft elastically rotates about its axis within the bearings. Structure is disclosed for coupling the rotational movement of the shaft to a utilization device.

Abstract: A capstan winch for pulling cable through conduit includes means for measuring the torque applied to the capstan and a take-up reel. The torque measuring means comprises an inner drum connected by a tension spring to a concentric outer drum. A patterned disc on the inner drum is visible through a window in the outer drum. The pattern indicates the relative position of the inner and outer drums, which is correlated to the applied torque.