Inductive displacement transducer using a bridge circuit having a stable voltage phase in the diagonal of the bridge
US3961243A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 17, 1974 |
| Grant date | Jun 1, 1976 |
| Priority date | — |
| Expiry date | May 17, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R17/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An inductive displacement transducer comprising a current measuring bridge circuit including a pair of adjustable electrical resistors coupled in series relationship in one half thereof, and a pair of series coupled induction coils and a movable magnetic armature in the other half of the bridge circuit. Each induction coil has the same inductance L when the armature is positioned symmetrically with respect to the coils, and the ohmic resistance R.sub.s of each bridge circuit branch which includes an induction coil is the same. The improvement of the invention comprises the provision of a pair of series coupled electrical shunt resistors, each coupled to one of the induction coils, having an electrical resistance R.sub.p which is determined by the equation R.sub.p =W.sup.2 L.sup.2 /R.sub.s Where WL is chosen so as to be substantially greater than R.sub.s. Alternatively, an electrically conductive tube may be disposed within the induction coils which has eddy current losses corresponding to the ohmic losses of the shunt resistors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.