Actuator-integrated force sensor

• US 6,772,647 B2
• Filed: 09/09/2002
• Issued: 08/10/2004
• Est. Priority Date: 12/07/1999
• Status: Expired due to Term

• Current Assignee: Pacifica Group Technologies Pty Limited
• Original Assignee: Pacifica Group Technologies Pty Limited
• Inventors: Spriegel, Dieter, Doemens, Guenter, Wuensche, Hans
• Primary Examiner(s): Lefkowitz, Edward
• Assistant Examiner(s): Ellington, Alandra
• Application Number:
  US10/148,948
• Publication Number:
  US 20030074977A1
• Time in Patent Office: 701 Days
• Field of Search: 738/624.72, 738/624.73, 738/624.74, 738/624.51, 738/623.91, 737/60, 737/81, 737/89, 737/88, 737/94, 737/95, 738/62
• US Class Current: 73/862.471
• CPC Class Codes: G01L 1/142 using capacitors
• CPC Class Codes: G01L 5/28 for testing brakes

Abstract

The present invention is based on an use of the already existing actuator bottom as a deformation element for a direct measurement of braking force, and on its geometric configuration in order to measure a force in a way which is largely independent of temperature and free of hysteresis. Accordingly, a force sensor is integrated into an actuator for generally or transmitting a force in the force flux. The actuator bottom is transverse to the force flux.

Claims

1. A device for measuring force in a force flux, comprising a force sensor integrated in an actuator, said actuator having a bottom which is formed transversely with respect to the force flux and on which the force acts centrally, and a supporting ring for transmitting the force, arranged peripherally on an outer edge of the actuator bottom in the direction of force, the actuator bottom capable of being deformed by the force and comprising part of the force sensor, whereby a detectable deformation of the actuator bottom constitutes a measure of the force, the deformation comprising a central deflection of the actuator bottom relative to the edge of said actuator, and the deflection being detectable by a plate capacitor configuration having an electrode positioned on an electrode mount which is pressed, with spring support, onto a base, and wherein the actuator bottom serves as a corresponding electrode.

2. A device for measuring force in a force flux, comprising a force sensor integrated in an actuator, said actuator having a bottom which is formed transversely with respect to the force flux and on which the force acts centrally, and a supporting ring for transmitting the force, connected peripherally on an outer edge of the actuator bottom in the direction of force, and an internal peripheral groove formed to reduce a cross section of the connection so that minimized temperature gradients occur in the direction of force in the actuator bottom and so as to result in a reduced mechanical coupling between the actuator bottom and supporting ring so that transmission of force from the actuator bottom to the supporting ring is minimized, the actuator bottom capable of being deformed by the force and comprising part of the force sensor, whereby a detectable deformation of the actuator bottom constitutes a measure of the force.

3. The device according to claim 2, wherein the deformation is detectable by means selected from one or more of the following:

inductive or optical measuring methods, metallic piezoresistive or semiconductor strain gauges, and strain sensors with silicon surface micromechanics.