Patent Number: 8,794,104

Title: Thermal ratchet system

Abstract: A thermal ratchet system includes a ratchet housing, a ratchet mandrel, a first ratchet, and a second ratchet. The first ratchet is disposed at a position generally fixed with respect to the ratchet housing and is urgeable with respect to the ratchet mandrel in an axial direction by a change in environmental temperature in a first direction. The second ratchet is disposed at a position generally fixed with respect to the ratchet housing and is urgeable with respect to the ratchet mandrel in the axial direction by a change in environmental temperature in a second direction opposite to the first direction. At least one of the first ratchet and the second ratchet is engaged with the ratchet mandrel.

Inventors: Stretch; Mitchel (Calgary, CA)

Assignee: Schlumberger Technology Corporation

International Classification: G05G 1/00 (20080401)

Expiration Date: 8/05/12018