Motion sensor

US5610590A · kind A · utility

Assignee

• The United States of America as represented by the Secretary of the Army · US

Inventors

• Mark A. Johnson · Santa Monica, US
• Thomas Simkins · Troy, US

Key dates

• Filing date: Feb 2, 1996
• Grant date: Mar 11, 1997
• Expiry date: Feb 2, 2016

Classification

• Technology area (CPC G): Physics
• CPC primary: G08B21/02
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

A motion detection monitor for patient movement, comprising a sensor for viding signals in response to patient movement to provide an alarm under predetermined conditions of patient movement. A processor, including an oscillator, is provided for receiving signals from the sensor, to provide oscillator interrupt signals proportional to active signals. The interrupt signals are observed within a contiguous series at time windows. The alarm condition is satisfied when interrup signals are detected within each window. The sensor preferably includes a conductive sphere in a cylinder having an interior portion locating the sphere therein with conductive end plates and conductive inner surfaces, the inner surfaces being tapered to direct the sphere to an at rest condition in contact with at least one surface and at least a part of the inner surface in any orientation of the sensor. The motion detection device further includes jumper circuits for adjusting the parameters used to distinguish from casual motion and for providing a visible alarm. The motion detection device further includes a remote, tetherless receiver for receiving the alarm signal, the transmitter means repeatedly providin…