Angular displacement sensors

• US 5,086,785 A
• Filed: 08/10/1989
• Issued: 02/11/1992
• Est. Priority Date: 08/10/1989
• Status: Expired due to Term

• Current Assignee: Freedom Multimedia LLC, Mattel Incorporated
• Original Assignee: Abrams Gentile Entertainment, Inc.
• Inventors: Goodman, Scott, Hall, Tracy, Fuller, Richard, Wallace, Michael, Avalon, Timothy D., Gentile, Christopher T.
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): Pontius, Kevin
• Application Number:
  US07/392,127
• Time in Patent Office: 915 Days
• Field of Search: 128/774, 128/782, 128/721, 338/2, 338/47, 338/114, 338/210-212
• US Class Current: 600/595
• CPC Class Codes: A61B 5/1121 Determining geometric values, e.g. centre of rotation or angular range of movement
• CPC Class Codes: A61B 5/1126 using a particular sensing technique
• CPC Class Codes: A61B 5/225 of the fingers, e.g. by monitoring hand-grip force
• CPC Class Codes: A61B 5/4528 Joints A61B5/4533, A61B5/4538 take precedence
• CPC Class Codes: G01D 5/16 by varying resistance
• CPC Class Codes: G01D 5/165 by relative movement of a point of contact or actuation and a resistive track
• CPC Class Codes: G01L 1/20 by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids of piezo-resistive materials G01L1/18; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
• CPC Class Codes: G01L 9/0002 using variations in ohmic resistance G01L9/0051 takes precedence

Abstract

A sensor for detecting angular displacement of an object. The sensor comprises a substrate for attachment to the object whose angular displacement is to be sensed and a sensing means attached to the substrate and connectable into an electric circuit. The electric circuit measures the resistance of the sensing means, which changes as a function of the angular displacement. Several embodiments are disclosed, including a conductive elastomer sensor, a conductive ink sensor, a sliding resistor sensor, a force sensitive resistor sensor and a conductive fluid sensor.

Claims

1. A sensor for detecting angular displacement of an object comprising:

a substrate for attachment to the object whose angular displacement is to be sensed;

sensing means attached to the substrate and connectable into an electric circuit, the sensing means comprising a material having an electrical resistance which changes as a function of the angular displacement, said material comprising an electrically conductive ink deposited on said substrate, said conductive ink comprising carbon particles in a binder and further comprising a solution of a first stretchable ink and a second brittle ink.

2. The sensor recited in claim 1, wherein said first and second inks are mixed in order to customize the sensor to an application, said first ink providing durability and said second ink providing a higher resistance range.

3. A sensor for detecting angular displacement of an object comprising:

a substrate for attachment to the object whose angular displacement is to be sensed;

sensing means attached to the substrate and connectable into an electric circuit, the sensing means comprising a material having an electrical resistance which changes as a function of the angular displacement, said material comprising an electrically conductive ink deposited on said substrate, and further comprising a highly conductive material deposited on the conductive ink in at least one selected area.