Patent · US Active

Free fall detection device

US7549335B2 · kind B2 · utility

36Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 17, 2006
Grant dateJun 23, 2009
Priority date
Expiry dateJun 17, 2026

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M2250/12
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A free fall detection device capable of detecting a fall accompanied by rotation is provided. A fall accompanied by rotation is detected based on a waveform of an acceleration signal output from the acceleration detection unit and an angular velocity signal output from the angular velocity detection unit. A gravity center acceleration of the device to be protected is calculated from the acceleration detected by the acceleration detection unit and from the angular velocity detected by the angular velocity detection unit. Even when the device being protected rotates as it falls, the fall of the device can be detected from the detected acceleration or angular velocity. Further, by calculating the gravity center acceleration not affected by the rotation, it is possible to detect a fall of the device with high precision even if the device rotates as it falls.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.