GB2097590A - Circuit breaker - Google Patents

Abstract

A circuit breaker comprises an insulating casing comprising a base 1 and a cover 2 mounting a stationary contact 3, a movable contact 4, a switching mechanism 6 for actuating said movable contact 4, a disconnecting mechanism 7 for permitting movement of said switching mechanism 6, and an electromagnetic release mechanism 8 for actuating said disconnecting mechanism in response to overload current in the circuit breaker. A pair of openings 1a, 1b are formed in said base 1, and secured thereto is a substantially U-shaped iron yoke 9 to which has its projecting legs 9a, 9b inserted through the openings 1a, 1b from the back of said base so as to surround a conductor 12 and attract a tripping armature 15 under overload conditions. <IMAGE>

Description

SPECIFICATION Circuit breaker Background of the invention Field of the invention The present invention relates to a mold type circuit breaker. More particularly, it relates to a fitting device of the stationary iron core of the automatical electromagnetic disconnecting mechanism in the circuit breaker.

Description of the prior art: Figures 1 and 2 show the conventional circuit breaker in which a mold casing comprising a base (1) and a cover holds a stationary contactor (3), a movable contactor (4), an extinguishing device (5), a switching mechanism (6), an automatic disconnecting mechanism (7) and so on. A statinary iron core (9), which is a part of an electromagnetic disconnecting section (8) of the automatic disconnecting mechanism (7), is secured by a screw (13) on the upper surface of a filter metal (10) which is embedded in the bottom of the base (1)so as to project therefrom, together with a conductor (12) which has one end connected to the movable contactor (4) and the other end connected to a bimetal (11).

In the conventional circuit breaker, the filler metal (10) is embedded when the base (1) is moulded. This causes disadvantages of requiring much time and labor for the molding and of difficulty in employing an automatic molding operation.

Summary ofthe invention It is an object of the present invention to overcome the disadvantages of the conventional circuit breaker by eliminating the filler metal.

The foregoing and the other objects of the present invention have been attained by providing a circuit breaker which comprises an insulation casing comprising a base and a cover and holding a stationary contactor, a movable contactor being detachable to said stationary contactor, a switching mechanism for actuating said movable contactor, a disconnecting mechanism for permitting mvoement of said switching mechanism, and an electromagnetic disconnecting mechanism for actuating said disconnecting mechanism in response to overlaod current in the conductor connected to said movable contactor, wherein a pair of openings are formed in said base, said stationary iron core is substantially U-shaped to give a pair of projecting portions facing said movable iron core, said stationary iron core being inserted from the back said of said base so as to surround said conductor and said iron core is secured to said base by a fitting means.

Brief description of the drawings: Figure lisa side sectional view of the conventional circuit breaker; Figure 2 is an enlarged fragmentary sectional view of Figure 1; Figure 3 is a side sectional view of an embodiment of the circuit breaker of the present invention; Figure 4 is an enlarged fragmentary sectional view of the circuit breaker shown in Figure 3; Figure 5 is a right side view of Figure 4; and Figure 6 is a plan view of Figure 6.

Detailed description of the preferred embodiment: An embodiment of the circuit breaker of the present invention will be described with reference to Figures 3to 6.

In the figures, a base (1) has a thin-walled portion (1c) in the bottom wherein a pair of rectangular openings (1 a), (1 b) are formed. A stationary iron core (9) is in a substantial U shape so as to give a pair of projections (9a), (9b) which are respectively passed through each opening (1 a) or (1 b) to face a movable iron core (15). A tapped hole (9d) is formed in the connecting part (9c) of the stationary iron core. A conductor (12) having one end connected to the movable contactor (4) and the other end connected to a bimetal (11) is held in the recessed portion of the stationary iron core (9). The conductor (12) is secured to the base (1) by screwing a screw (13) through a hole formed in a thin-walled portion (ic) of the base (1) into the tapped hole (9b) of the stationary iron core (9).The reference numeral (14) designates a washer.

With this structure of the present invention eliminating a filler metal, a base can be easily molded and manufacturing cost can be reduced by using automatic molding. Turning of the stationary iron core is prevented because the iron core is inserted into a pair of openings formed in the base whereby positional relationship of the stationary iron core to the movable iron core can be maintained. The distance between the stationary iron core and the movable iron core can be varied by putting spacers therebetween so that current intensity for the attractive force can be easily changed.

1. In a circuit breaker comprising an insulation casing including a base and a cover and holding a stationary contactor, a movable contactor being detachable to said stationary contactor, a switching mechanism for actuating said movable contactor, a disconnecting mechanism for permitting movement of said switching mechanism, and an electromagnetic disconnecting mechanism for actuating said disconnecting mechanism in response to overload current in the conductor connected to said movable contactor, an improvement characterized in that a pair of openings are formed in said base, said stationary iron core is substantially U-shaped to give a pair of projecting portions facing said movable iron core, said stationary iron core being inserted from the back side of said base so as to surround said conductor and said iron core is secured to said base by a fitting means.

2. A circuit breaker according to Claim 1 wherein said fitting means is a fitting screw which engaged said stationary iron core with said base through said conductor.

3. A circuit breaker according to Claim 1 or 2 wherein a spacer is put between the connecting portion of said iron core and said base.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Circuit breaker Background of the invention Field of the invention The present invention relates to a mold type circuit breaker. More particularly, it relates to a fitting device of the stationary iron core of the automatical electromagnetic disconnecting mechanism in the circuit breaker. Description of the prior art: Figures 1 and 2 show the conventional circuit breaker in which a mold casing comprising a base (1) and a cover holds a stationary contactor (3), a movable contactor (4), an extinguishing device (5), a switching mechanism (6), an automatic disconnecting mechanism (7) and so on. A statinary iron core (9), which is a part of an electromagnetic disconnecting section (8) of the automatic disconnecting mechanism (7), is secured by a screw (13) on the upper surface of a filter metal (10) which is embedded in the bottom of the base (1)so as to project therefrom, together with a conductor (12) which has one end connected to the movable contactor (4) and the other end connected to a bimetal (11). In the conventional circuit breaker, the filler metal (10) is embedded when the base (1) is moulded. This causes disadvantages of requiring much time and labor for the molding and of difficulty in employing an automatic molding operation. Summary ofthe invention It is an object of the present invention to overcome the disadvantages of the conventional circuit breaker by eliminating the filler metal. The foregoing and the other objects of the present invention have been attained by providing a circuit breaker which comprises an insulation casing comprising a base and a cover and holding a stationary contactor, a movable contactor being detachable to said stationary contactor, a switching mechanism for actuating said movable contactor, a disconnecting mechanism for permitting mvoement of said switching mechanism, and an electromagnetic disconnecting mechanism for actuating said disconnecting mechanism in response to overlaod current in the conductor connected to said movable contactor, wherein a pair of openings are formed in said base, said stationary iron core is substantially U-shaped to give a pair of projecting portions facing said movable iron core, said stationary iron core being inserted from the back said of said base so as to surround said conductor and said iron core is secured to said base by a fitting means. Brief description of the drawings: Figure lisa side sectional view of the conventional circuit breaker; Figure 2 is an enlarged fragmentary sectional view of Figure 1; Figure 3 is a side sectional view of an embodiment of the circuit breaker of the present invention; Figure 4 is an enlarged fragmentary sectional view of the circuit breaker shown in Figure 3; Figure 5 is a right side view of Figure 4; and Figure 6 is a plan view of Figure 6. Detailed description of the preferred embodiment: An embodiment of the circuit breaker of the present invention will be described with reference to Figures 3to 6. In the figures, a base (1) has a thin-walled portion (1c) in the bottom wherein a pair of rectangular openings (1 a), (1 b) are formed. A stationary iron core (9) is in a substantial U shape so as to give a pair of projections (9a), (9b) which are respectively passed through each opening (1 a) or (1 b) to face a movable iron core (15). A tapped hole (9d) is formed in the connecting part (9c) of the stationary iron core. A conductor (12) having one end connected to the movable contactor (4) and the other end connected to a bimetal (11) is held in the recessed portion of the stationary iron core (9). The conductor (12) is secured to the base (1) by screwing a screw (13) through a hole formed in a thin-walled portion (ic) of the base (1) into the tapped hole (9b) of the stationary iron core (9).The reference numeral (14) designates a washer. With this structure of the present invention eliminating a filler metal, a base can be easily molded and manufacturing cost can be reduced by using automatic molding. Turning of the stationary iron core is prevented because the iron core is inserted into a pair of openings formed in the base whereby positional relationship of the stationary iron core to the movable iron core can be maintained. The distance between the stationary iron core and the movable iron core can be varied by putting spacers therebetween so that current intensity for the attractive force can be easily changed. CLAIMS

1. In a circuit breaker comprising an insulation casing including a base and a cover and holding a stationary contactor, a movable contactor being detachable to said stationary contactor, a switching mechanism for actuating said movable contactor, a disconnecting mechanism for permitting movement of said switching mechanism, and an electromagnetic disconnecting mechanism for actuating said disconnecting mechanism in response to overload current in the conductor connected to said movable contactor, an improvement characterized in that a pair of openings are formed in said base, said stationary iron core is substantially U-shaped to give a pair of projecting portions facing said movable iron core, said stationary iron core being inserted from the back side of said base so as to surround said conductor and said iron core is secured to said base by a fitting means.

2. A circuit breaker according to Claim 1 wherein said fitting means is a fitting screw which engaged said stationary iron core with said base through said conductor.

3. A circuit breaker according to Claim 1 or 2 wherein a spacer is put between the connecting portion of said iron core and said base.

4. A circuit breaker substantially as herein particularly described with reference to and as illustrated in Figures 3 to 6 of the accompanying drawings.