US 9,803,664 B2 · System for position measuring and integrity measuring

Abstract

A system for measuring the position of a rod element as, for example, a hydraulically or pneumatically operated piston rod. Unlike the prior art, the system according to the present invention employs a measuring principle that does not require preparatory treatment of the rod element as is required in the known solutions. The system employs direct time of flight measurements with the aid of acoustic surface waves that are introduced into the rod element. The instrument is retrofittable on existing cylinders without any modification/reconstruction thereof. An EMAT principle is employed to introduce the surface waves into the measurement in a non-contact manner.

Claims11

Dependent claims

A system for a pneumatic or hydraulic cylinder, linear guide, damper, or rod element, adapted to provide position measurement by the distance to one and/or both ends of a translatory and/or rotary element,

wherein an ultrasound-based time of flight measurement is used directly in the translatory and/or rotary element, and that sound waves for the time of flight measurement are generated by a sensor in the form of an EMAT which generates and detects the sound wave, wherein permanent magnets of the sensor are distributed around a circumference of the translatory and/or rotary element and the permanent magnets have a corresponding orientation in the radial direction of the translatory and/or rotary element with respect to their individual north and south orientation.

Dependencies are inferred from the claim text.

System for position measuring and integrity measuring

Life of this patent

System for position measuring and integrity measuring

Life of this patent

Abstract

Claims11