Inductive sensing apparatus for a hydraulic cylinder
US5438261A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 16, 1994 |
| Grant date | Aug 1, 1995 |
| Priority date | — |
| Expiry date | Feb 16, 2014 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF15B15/28
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In one aspect of the present invention, an apparatus for determining an extended length of a hydraulic cylinder is disclosed. A piston and rod are contained within a cylindrical housing of the hydraulic cylinder. A coil is wound about the rod and is attached to the piston and an end of the cylindrical housing. The coil extends and retracts with the reciprocating movement of the piston. An oscillator is coupled to the coil and produces a position signal in response to the inductance of the coil. A circuit receives the position signal, and determines the incremental linear position and velocity of the piston and rod relative to the housing in response to the frequency of the position signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.