Pressure operated electric switch and alarm system using such switch

摘要

A pressure operated electrical switch and an alarm system for use in hospitals and nursing homes is constructed such that a force is applied to the upper surface of a leaf spring therein. Once the load is reduced below a predetermined value the leaf spring will move to close/open a microswitch or electrical contact means. The normal force applied to the leaf spring is the load on the leg of the hospital bed when occupied. If the bed occupant gets out of the bed the load on the leaf spring is reduced below a predetermined value and the consequent movement of the leaf spring opens/closes the switch means to actuate the alarm.