Technology Offers

Phase-analog displacement sensor – Inexpensive and inductive, even contactless

Abstract

The inductive sensor principle, which also works contactless, enables a phase-analogue and robust detection of paths or angles in all areas of industrial automation, automotive engineering, traffic engineering or medical technology. Large path lengths from a few centimeters up to many meters with analog resolution can preferably be measured.

Background

The new sensor principle enables phase-analog, reliable recording of paths in all areas of industrial automation, including automotive engineering, traffic engineering and medical technology. The sensor that performs analog resolution measurements can be built in almost any length, from a few centimeters to several tens of meters or even longer. The path measured may also be curved, in which case the sensor is used as an angle meter.

Problem

The new sensor principle enables phase-analog, reliable recording of paths in all areas of industrial automation, including automotive engineering, traffic engineering and medical technology. The sensor that performs analog resolution measurements can be built in almost any length, from a few centimeters to several tens of meters or even longer. The path measured may also be curved, in which case the sensor is used as an angle meter.

Solution

The new phase-analog displacement sensor uses a signal chain that generates electromagnetic alternating fields along the path. Those fields show linear phase shifts along the path compared to the feeding alternating source. At the position to be recorded, a voltage is generated at a receiver whose phase is used as a measure for the position to be measured. Voltage transfer can take place via cable or can be contactless (in which case the receiver does not require external cabling). Even at large vertical distances from the signal chain, the phase can precisely be determined using an interference-free correlation method. In the horizontal direction of use, the sensor can achieve any resolution required.
In addition to a robust, inductive version, a contactless capacitive or optical version is also feasible. The sensor does not require any complex housing technology and can be manufactured inexpensively.

Advantages

  • Sensor lengths from centimeters to several tens of meters or longer
  • Large distance possible between signal transmitter and sensor
  • Analog linear displacement sensor with any resolution required
  • Total error less than 0.2 %
  • No sensor calibration required
  • High interference immunity
  • Sensor available without external cabling

Application

An essential field of application is the large area of automation technology and in particular, of course, hydraulics.
For motor vehicles, engine control and transmission as well as path detection for doors, windows and seats can be mentioned as examples.
Many special applications can occur in critical environmental areas with a high moisture and dirt content.

Exposé
Contact
Dr.-Ing. Michael Ott
TLB GmbH
Ettlinger Straße 25
76137 Karlsruhe | Germany
Phone +49 721-79004-0
ott(at)tlb.de | www.tlb.de
Development Status
Prototype / TRL5
Patent Situation
DE 102006012952 B4 granted
EP 1996900 B1 granted,
DE, FR, GB validated
Reference ID
137/05TLB
Service
TLB GmbH is in charge of the management of the invention till it is marketable and offers companies the opportunity of licensing or cooperation for advancements.