Piezoresistive input device
US5510812A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 22, 1994 |
| Grant date | Apr 23, 1996 |
| Priority date | — |
| Expiry date | Apr 22, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0338
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An input device for computers or electronic games using piezoelectric elements. Four piezoelectric devices are mounted on a base in positions ninety degrees apart. A user actuation element, such as a directional control pad and or a joystick is pivotally disposed on the base above the piezoelectric sensors. A biasing element such as a spring, foam or rubber element is positioned between the actuation element and the base to support the actuation device in a neutral position when no face is being applied by a user to also return the activation element to its neutral position after a user's force is removed. Opposing sensors are connected to a bridge circuit such that in the neutral position of the actuation element the output voltage of the bridge is one half of the input voltage. As the user applies a force to the actuation device, the resistance of one or the other (opposing) piezoresistive device will decrease and accordingly drive the output of the bridge circuit either towards the input voltage or ground, depending on which sensor the user is activated. Additionally a piezoresistive device constructed according to the present invention uses a conductive foam overlayed on top of…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.