Capacitive proximity sensor

Patent · 31 May 1994

OSTI ID:7183883

Kronberg, J W

A proximity sensor based on a closed field circuit is disclosed. The circuit comprises a ring oscillator using a symmetrical array of plates that creates an oscillating displacement current. The displacement current varies as a function of the proximity of objects to the plate array. Preferably the plates are in the form of a group of three pair of symmetric plates having a common center, arranged in a hexagonal pattern with opposing plates linked as a pair. The sensor produces logic level pulses suitable for interfacing with a computer or process controller. The proximity sensor can be incorporated into a load cell, a differential pressure gauge, or a device for measuring the consistency of a characteristic of a material where a variation in the consistency causes the dielectric constant of the material to change. 14 figs.

• DOE Contract Number: AC09-89SR18035
• Assignee: Dept. of Energy, Washington, DC (United States)
• Patent Number(s): US 5315884; A
• Application Number: PPN: US 7-756669
• OSTI ID: 7183883
• Country of Publication: United States
• Language: English

Related Subjects

440800* -- Miscellaneous Instrumentation-- (1990-)
47 OTHER INSTRUMENTATION
COMPUTERS
CURRENTS
DESIGN
DISPLACEMENT GAGES
ELECTRIC CURRENTS
MEASURING INSTRUMENTS
POSITIONING
PRESSURE GAGES
PROCESS COMPUTERS