Patent ID: 6693502
Filing Date: 2004-02-17
Classification: H02B

Abstract:
In an air circuit breaker comprising;a movable breaker body having a power source terminal and a load terminal and connecting or disconnecting a circuit between an electrical power source and an electrical load; a cradle electrically and mechanically connected to or separated from the breaker body in accordance with movement of the breaker body and having a connector electrically and mechanically connected to the breaker body, a screw pipe for guiding the contact/separation to/from the breaker body and a power source terminal and a load terminal respectively connected to the electrical power source and the electrical load; a base frame fixed to the breaker body; a lead screw supported by the base frame so as to be rotatable and movable to a position for being inserted into the screw pipe and a position for being separated from the screw pipe; a interlock apparatus installed to the base frame and for indicating a position of the breaker body such as a disconnected position in which the breaker body is totally separated from the cradle, a testing position for testing the breaker body and a connected position in which the breaker body is connected to the cradle, the interlock device comprising; a first lead bar extended from the base frame toward the front end of the lead screw in parallel with the lead screw and generating a dynamic power for indicating a position of the breaker body by moving in a direction opposite to a forward direction of the lead screw when the lead screw is inserted into the screw pipe; a guide member installed so as to be movable on the lead screw in the base frame, connected to the first lead bar and performing a horizontal linear movement corresponded to the movement of the first lead bar; a second lead bar constructed separately from the first lead bar, connected to the guide member in the base frame and performing a horizontal linear movement corresponded to the movement of the guide member; a spring installed on the lead screw in the base frame and for applying an elastic force on the first lead bar in a forward direction of the lead screw; a cam connected to the second lead bar and for transforming the linear movement of the second lead bar into rotating movement; and a indicating means connected to the cam and for indicating a position of the breaker body.