Capacitive sensing apparatus for sensing a plurality of operating parameters associated with a variable displacement piston pump
US6152702A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 1999 |
| Grant date | Nov 28, 2000 |
| Priority date | — |
| Expiry date | Mar 24, 2019 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B2205/09
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An apparatus and method for sensing a parameter of a hydraulic pump. The hydraulic pump includes a housing and an input shaft. The shaft is rotationally driven relative to the housing and electrically coupled to the housing. The hydraulic pump forms a variable capacitor. The apparatus includes an electrode portion positioned adjacent to the input shaft and is electrically isolated from the housing and input shaft. The electrode portion and the input shaft form a fixed capacitor. The fixed capacitor and the variable capacitor are coupled. The apparatus supplies electrical energy to the electrode portion and produces a capacitive signal indicative of the capacitance value of the variable capacitor. The apparatus further applies a filter to the capacitive signal and produces a filtered capacitive signal. The parameter of the hydraulic pump is determined as a function of the filtered capacitive signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.