System for position measuring and integrity measuring

Registre Brevet USPTO
Numéro d'application 14397800
Numéro de brevet 09803664
Statut Délivré - en vigueur
Date de dépôt 2013-04-29
Date de la première publication 2015-03-26
Date de publication 2015-03-26
Date d'octroi 2017-10-31
Propriétaire TECHNI AS (Norvège)
  • Petersen, David Christian
  • Bendiksen, Jan Martin
  • Schmedling, Petter F.
  • Karlsen, Morten Roll
  • Eisenträger, Roland
  • Kolle, Audun G.


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.

Classes IPC  ?

  • F15B 15/28 - Means for indicating the position, e.g. end of stroke
  • F15B 19/00 - Testing fluid-pressure actuator systems or apparatus, so far as not provided for elsewhere
  • G01D 5/48 - Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using wave or particle radiation means
  • G01S 15/02 - Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves