Alarm system for personal defence - has two mercury switches contained in armbands so that switches close when arms are raised to actuate alarm

摘要

The anti-aggression alarm system uses two mercury switches (2) each switch being located in an armband (1) worn by the person to be protected. These switches (2) are connected in series and close when the arms are raised. Closure of the mercury switches (2) actuates a portable radio transmitter (5) carried on the person. In a cloth sheath or other appropriate material (3) are placed the conductors interconnecting the two mercury switches (2). A cloth or other sheath (4) carries conductors which interconnect the switches (2) with the radio transmitter (5). The aerial (6) of the system is placed in a trouser leg.