Signal processing for contact-sensing probe
US4916339A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 26, 1988 |
| Grant date | Apr 10, 1990 |
| Priority date | — |
| Expiry date | Apr 26, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B5/012
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A probe (12) is connected to an interface circuit (10). The probe (12) has two different types of contact sensors, namely a piezo electric sensor and an electro-mechanical switching sensor. The trigger signal from the piezo electric sensor is detected by circuits (34,36,38,40) while that from the switching sensor is detected by a comparator (32). The signals are mixed in a mixer (42) to produce a single output trigger signal. A monostable (48) and latch (50) discriminate which sensor produced the output signal, making use of the inherent time delay between the two sensor signals. Circuits (24,26,28) determine if a conventional switching probe has been connected instead of the probe (12). If so, a transistor (T4) varies the power supply to the probe, and gates (30,33) switch in a comparator (18) in place of the comparator (32).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.