| 摘要 |
A automatic breaker consists of a body comprising a cover and a basis, a contact system, which includes a movable and a fixed contacts in every pole, an explosion chamber in every pole, a trip-free release mechanism made as a system of pivotally connected levers, which connects start and stop buttons with a movable contact assembly, an overcurrent release device. The fixed contact is connected with output terminals for connection of voltage to the circuit breaker. The movable contact is installed in a holder for movable contacts, being turnable and by means a flexible current conductor connected with a thermal release device and output terminals of the circuit breaker. The overcurrent release device in every pole is connected by means of current conductors with circuit breaker output terminals to connect a load. The trip-free release installed on the bases consists of two side figured supports, between which a plate with slots for traveling start and stop buttons is fastened. Buttons are made from insulating material with plates and provided with pull-back springs. In a start button plate it is made a figured slot for traveling of two pair of pivotally connected drivers along a common axis. One of pairs is connected with a clutch arm with an end rested on a half-sawn-down axis. The said axis is installed in figured supports and provided with a spring-loaded thrust lever, on which in case of circuit overloads a rotary shutdown bar by means of the crank arm installed in a side figured support acts. The other pair of drivers is installed at the axis located in the slot of the holder of movable contacts. The axis is spring loaded with an operative spring. Action of the overcurrent release device to the trip-free release mechanism is realized by means of the shut-down bar installed on a basis. |
