US 5,331,301 AGranted

Circuit breaker

AssigneeSquare D Company

InventorsOliver Glennon, James Early, James Shortt, Martin F. Healy, Hendrik A. Bosch, Soedjiemat F. Darmohoetomo, Raymond Burke

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Abstract

A residual current circuit breaker 1 has a partition wall 3 which separates an over-current protection device 4 from a residual current detection circuit 5. A plunger rod 24 extends through a bore 23 in the armature 21 of a coil 20 and is moved independently through the coil 20 to trip the breaker if a residual current is detected by the circuit 5. The plunger rod 24 is moved by a drive rod 31, the operation of which is controlled by a permanent magnet which retains the drive rod 31 retracted and an electromagnet which allows the drive rod 31 to drive forwardly under the action of a spring 32 in the event of a residual current being detected. The plunger rod 30 is reset by a reset lever 40 which is moved when an operating handle 18 of the breaker moves from a non-tripped to a tripped position on tripping of the breaker.

Claims19

Dependent claims

A circuit breaker for use in a system having live, neutral and ground leads, comprising:

a housing;
a breaker assembly in the housing for making and breaking an electrical connection between a movable contact and a stationary contact;
an operating handle for the breaker assembly;
an over-current sensing means for tripping of said breaker assembly;
the over-current sensing means including a coil and an armature core in the coil;
the armature core having an axial bore extending therethrough;
and an additional tripping mechanism;
the additional tripping mechanism comprising:
a plunger means mounted within the axial bore of the armature core;
an actuating device for controlling the movement of the plunger means from a non-tripping position to a tripping position;
the plunger means being independently movable through the axial bore in the armature core when moving between the non-tripping and tripping positions, and
reset means being provided for re-setting of the plunger means to the non-tripping position.

9 more elements

Dependencies are inferred from the claim text.