Apparatus for measuring the angular position of a shaft
US4443787A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 9, 1982 |
| Grant date | Apr 17, 1984 |
| Priority date | — |
| Expiry date | Mar 9, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/30
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus is disclosed, for measuring the angular position of a shaft of a machine at the occurrence of an event originating from the operation of the machine, relative to a reference position of the shaft. The apparatus comprises a first sensor responsive to the reference position of the shaft (signal II) and a second sensor which, on the occurrence of the event, produces an output pulse and which produces a number of interference pulses in the periods between production of the output pulses (signal I). A comparator (4) having a threshold value which is capable of being exceeded both by the required pulses and the interference pulses, and a recognition circuit (3,6) which is adapted to recognize output pulses produced on the occurrence of the event, are arranged to control an evaluation circuit such as a counter (10). The evaluation circuit ascertains, e.g. by counting angular increment marker pulses (signal III), the angle through which the shaft rotates between the time when the threshold of the comparator (4) was last exceeded prior to triggering of the recognition circuit by the required event, and the time when the shaft reaches the reference position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.