Play measuring sensor by multiple depth abrasion

摘要

A device for measuring a clearance between tips of blades of a ring of blades and an interior wall of a casing surrounding the ring of blades in a turbomachine includes a probe which is mounted radially on the casing. The probe has an end made of a material that can be abraded by the tips of blades as they rotate. The device also includes a printed circuit arranged in a mid-plane of the probe. The probe contains an axis of rotation of the ring of blades. Further, the printed circuit includes a number of adjacent U-shaped electrical circuits that have bases arranged in a probe end likely to be abraded by the tips of blades. The bases lie at different depths from a reference level defining the interior wall of casing. The printed circuit also includes a recognizer for determining which U-shaped electrical circuits have been broken by abrasion and which U-shaped electrical circuits are intact.