Abstract: A multipolar circuit breaker is provided for securely operating tripping sections of other poles when the tripping section of any pole operates. In the case of a first embodiment, a protrusion 5 for further moving a trigger plate in the tripping direction when a cradle 3 is tripped is provided for the cradle 3 of each pole so that the movement of the trigger plate 1 is securely transmitted to other poles connected by a trigger joint 2. Moreover, in the case of a second embodiment, a protrusion for further moving the trigger plate 1 in the tripping direction by pushing the cradle 3 when the cradle 3 is tripped is provided for the trigger plate of each pole to obtain the same above mentioned advantage.

Abstract: A handle portion of a multipole breaker includes a handle main body, made of an insulating material, for ON/OFF operation of the multipole breaker. Movable fingers having respective movable contacts are provided for opening and closing of respective circuits, and a connecting section is interposed between the handle main body and the movable fingers for transmitting ON/OFF operation of the handle main body to the movable fingers. The connecting section has at upper positions thereof one of: (i) openings for receiving shafts formed on side walls and a center wall of a breaker case, and (ii) shafts to be fitted in recesses defined in the side walls and the center wall of the breaker case. In addition, the handle main body has, on a bottom portion thereof, a partition for insulating adjacent poles.

Abstract: A molded-case multicircuit breaker which suffers insufficient contact pressure at no poles and which is free from damage. The molded-case multicircuit breaker having at least two circuits comprises a handle which performs on-off operation of the circuits simultaneously, a first finger having a movable contact for a first circuit, and another finger having a movable contact for a circuit other than the first circuit, wherein the first finger is designed to be switched on and off directly by the handle, and the finger for a circuit other than the first circuit is electrically insulated from the first finger and is attached resiliently to the first finger. The second finger may be pivotally attached or spring loaded to the first finger.

Abstract: An earth leakage breaker has a case, a handle protruding from the case, a cradle for determining stable positions of the handle, and a movable finger including a movable contact at a bottom portion of the movable finger. The movable finger is pivotally jointed to the handle at a protrusion provided on a lower side of the handle. An extension spring spans between the cradle and the movable finger, and a top-end swinging trigger plate is provided for engaging the cradle. The trigger plate has a fulcrum at a bottom portion thereof, and a test button and a leak trip solenoid are adjacently arranged at a top portion of the case, with the leak trip solenoid having a trip piece engaged with a contact portion formed on a top portion of the trigger plate for effecting circuit breaking due to a leak.

Abstract: A distribution circuit breaker for two circuits operated by a common handle, in which an arc gas generated in one circuit is prevented from flowing into the other circuit includes a breaking mechanism chamber (A) for a first circuit and another breaking mechanism chamber (B) for a second circuit are defined in a single circuit breaker case on each side of a partition (3a). Contact driving means (8) is forked at the lower end portion to have two fingers which are positioned on each side of the partition and to be spaced from each other, and movable contacts (10a,10b) are attached to the lower end portions of the fingers, respectively. An arc gas suppressing barrier is provided with respect to at least one movable contact.