Patent ID: 6111327
Filing Date: 2000-08-29
Classification: H01H

Abstract:
An automatic power cut-off device for emergency situations comprising:a solenoid electrically connected at one input terminal thereof to an external negative voltage input terminal, said solenoid having an engagement extension reciprocating along a straight path when said solenoid is activated;a pair of connecting terminals arranged in parallel to each other, one of said connecting terminals being electrically connected to an external positive voltage input terminal, and the other one of said connecting terminals being electrically connected to a load;a fixed bar attached at one end thereof to one of said connecting terminals;a pivotal bar electrically connected to the other one of said connecting terminals and pivotally mounted at one end thereof in such a fashion that it pivots between a first position, in which it is in contact with said fixed bar, thereby electrically connecting said connecting terminals with each other, and a second position, in which it is separated from said fixed bar, thereby electrically disconnecting said connecting terminals from each other, said pivotal bar having an engagement portion at the other end thereof;a tension coil spring adapted to urge said pivotal bar toward said second position;a return knob arranged in such a fashion that it pivots between two positions respectively corresponding to said first and second positions of said pivotal bar to return said pivotal bar from said second position to said first position against a spring force of said tension coil spring, said return knob having a first engagement portion engaging with said engagement extension in an inactive state of said solenoid to maintain said pivotal bar at said first position, and a second engagement portion always engaging with said engagement portion of said pivotal bar; andan impact sensing device comprising an impact sensor adapted to sense an impact, thereby generating an impact sensing signal, said impact sensing device allowing a positive voltage from said positive voltage input terminal to be applied to said solenoid for an activation of said solenoid, in response to said impact sensing signal;whereby said engagement extension of said solenoid is disengaged from said first engagement portion of said return knob when said impact sensor senses an impact, so that said pivotal bar pivots to said second position by virtue of said spring force of said tension coil spring, thereby cutting off the supply of said positive voltage.