Capacitive gauging system utilizing a low internal capacitance, high impedance amplifier means
US4190797A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1978 |
| Grant date | Feb 26, 1980 |
| Priority date | — |
| Expiry date | Mar 31, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B7/023
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A capacitive gauging apparatus in which a single central processing unit is connected to a plurality of gauging heads each gauging head having a further plurality of gauging probes. The system then multiplexes the probes and heads to enable the central processing unit to receive serially the output from each of the heads and produce an analog or digital signal which indicates distance between each of the probes and the work piece. A central microprocessor transforms these signals into an output for visual display or calculates the difference between these signals and an ideal master work piece. Further, a highly temperature stable, low capacitance, high impedance amplifier is used in conjunction with each of the probes so that the output signal from each of the probes is stable and accurate over a wide range of conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.