Device for converting the amount of a mechanical displacement into electrical signal
US4634126A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 26, 1985 |
| Grant date | Jan 6, 1987 |
| Priority date | — |
| Expiry date | Mar 26, 2005 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA63F2003/00665
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A transducer converts the amount of mechanical displacement of a member into an electrical signal by magnetic induction. Two fixed coils different in winding direction from each other are spaced apart from each other by a suitable distance and connected in series. Inside the fixed coils, a movable coil is disposed which moves in cooperative association with the member whose amount of movement is to be detected. With the movable coil supplied with an a.c. current, the fixed coils produce an induction current whose amplitude varies with the relative position of the movable coil. A signal processing circuit generates a pulse having a duty ratio corresponding to the amplitude of the induction current. This pulse is converted into a d.c. current in a smoothing circuit to obtain a d.c. voltage corresponding to the amount of mechanical displacement. In a pinball machine, the amount of this voltage regulates the force with which the plunger of a solenoid strikes a ball, thereby to correlate the amount of movement of a handle manipulated by the player with the trajectory of the ball on a playing field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.