Measuring device for capacitive determination of the relative position of two with respect to one another moveable parts
US4420754A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 9, 1981 |
| Grant date | Dec 13, 1983 |
| Priority date | — |
| Expiry date | Jun 9, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/2415
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system for measuring the relative movement between two elements, such as the scale and slide of a hand-held measuring instrument includes the provision of a number of groups of supply electrodes on the slide, each of the electrodes in each group being supplied from a respective one of a multiple number of output signals from a signal generator so that all of the supply electrodes are furnished with voltages according to a cyclic pattern, the slide also having at least one receiving electrode which feeds a signal processing unit. The scale is provided with an electronic pattern comprising internally galvanically connected parts, one being a detecting part, located close to the area where the supply electrodes of the slide are moved, the other of the two parts being a transferring part which is located close to the area where the receiving electrode of the slide is moved. The movement of the slide along the scale generates a signal from the receiving electrode which is derived from the signals from at least two adjacent supply electrodes and the position of the slide is determined by a signal processing unit which identifies the amplitude ratio of the received signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.