Cordless headphone system for radio listening and with automatic disconnection of battery

摘要

The receiver is mounted with the battery casing (1) on the headband (5) which carries also a magnetically operated switch (2). The earpiece (3) is pivoted (6) on the end of the casing so that when removed from the head it is attracted with the magnet (4) towards the switch, and opens it automatically. The movement can be assisted by e.g. a spring in the earpiece. It can be activated alternatively by a mechanical, pneumatic, ohmic or hydraulic pressure switch, closed when the headphones are worn, or by variation of mechanical tension in the headband, or by detection of thermal radiation from the head.