Personal motion event monitor
US5879309A · kind A · utility
Inventors
Key dates
| Filing date | Aug 11, 1997 |
| Grant date | Mar 9, 1999 |
| Priority date | — |
| Expiry date | Aug 11, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B21/02
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A motion detection device for monitoring patient movement. The device includes a sensor adapted to generate a voltage from mechanical vibrations and a circuit in operable relationship with the voltage for generating an alarm upon detection of a predetermined signal. The circuit provides a fixed impedance to the sensor. A micro controller is used for analyzing the signal to select from first and second conditions by sensing activity within sequences of preselected time intervals. The first condition represents a medical condition and the second condition represents casual motion. A switch is used for setting a time interval and a total sampling time for the micro controller. An alarm signal generates an alarm upon detection by the microprocessor of a predetermined activity. The preferred sensor comprises a housing having an outer shell and a hollow spherical opening therein. A plurality of inner spherical bodies are adapted to move freely inside the spherical opening to produce detectable mechanical vibration in the outer shell. A piezoelectric film is attached to a portion of the outer shell to generate a voltage from the mechanical vibrations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.