JPS59167934A - Circuit breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] This invention relates to a circuit breaker, and in particular aims to improve the breaking performance of a circuit breaker in which a contactor of a nameplate is housed in an insulating case for each name together with an arc extinguishing device. It is something.

Generally, an air circuit breaker generates an air arc when interrupting current. This generated arc is arc plasma generated from a metal electrode, and the center is a gas containing high-temperature, high-pressure metal ions.

This gas will tend to diffuse into the surrounding area if no measures are taken, but in order to shut it off safely, it is necessary to suck it into the arc extinguishing device in the arc extinguishing room and cool it as quickly as possible. . There are various types of arc extinguishing devices, but the de-ion grid system is usually used, in which a large number of magnetic plates with U-shaped notches are insulated from each other, with the notches facing the arc. There is. The generated arc is drawn into the arc extinguishing device by the magnetic attraction force of these arc extinguishing devices. This attraction effect may be made more effective by the magnetic effect that the interrupted currents flowing through the fixed and movable conductors have on the arc. Furthermore, the breaking part of the air circuit breaker is completely shielded by an insulating case for each multi-pole, so when an arc occurs, the pressure rises in the space other than the arc extinguishing chamber and the exhaust port, and the arc is exhausted. It has been thought that this makes it easier to diffuse toward the arc-extinguishing chamber side where the opening is located, thus providing an effective cooling effect. This type of circuit breaker is manufactured as a distribution circuit breaker (molt case circuit breaker), and the insulator case of this circuit breaker is a rectangular parallelepiped insulator case consisting of a molded base and a molded cover. In general, a movable contact device is opened and closed by rotational movement around an axis located on the base side, and in the open state, it stands still at an inclined position with respect to the rectangular parallelepiped insulator case, so the movable contact device The side surface shape creates an X' triangular space on the back surface.

It is well known that this space is used to attach accessories such as auxiliary switches and voltage tripping devices as necessary.

However, the existence of this triangular space reduces the internal pressure in the arc extinguishing chamber when an arc occurs, and airflow is generated from the arc extinguishing chamber toward this space, which reduces the arc that occurs between the fixed and movable contacts. This has the disadvantage that it has the opposite effect on the originally intended action of attracting it into the arc extinguishing chamber and exhausting it through the exhaust port, reducing the blocking performance. In addition, the above-mentioned accessories are often exposed to high-temperature, high-pressure gas and lose their functionality, and on top of that, the movable contact device has a crossbar around the shaft that connects multiple poles, and the insulating case has multiple parts. Although it penetrates the partition of the electrode chamber, it has the disadvantage that the insulation between the electrodes is not threatened by the arc gas that flows back as described above.

Therefore, the purpose of the present invention is to eliminate the above-mentioned conventional drawbacks, prevent arc gas from flowing back into the space created on the back side of the movable contact device, and improve interrupting performance by preventing a drop in the internal pressure of the arc extinguishing chamber. It is an object of the present invention to provide a circuit breaker that prevents damage to accessories and a decrease in dielectric strength between the poles.

To summarize the invention, a wide movable arc gas restraining member includes an arcuate surface attached to a contact holder of a movable contact device rotating about a fixed shaft, and extends in the direction of movement when opening the circuit; A space is formed on the back surface of the movable contact device by a fixed arc gas suppressing member formed on the inner circumferential wall of the insulator case so as to have a surface facing the circular arc surface of the movable arc gas suppressing member and extending inward. , a shielding partition is provided between the arc extinguishing chamber side space and the arc extinguishing chamber side space.

The above objects and other objects and features of the invention will become more apparent from the following detailed description with reference to the drawings.

Figures 1 to 9 show an embodiment of a three-pole circuit breaker according to the present invention. It is formed. This mold base l and mold cover 21 are provided with storage grooves partitioned by different polarity insulating partition walls /a for storing the main multi-pole components, and by combining the mold base / and mold cover - A multi-polar main conductor is housed in a room partitioned by a completely rounded partition wall.

In FIGS. 1 and 2, to explain the center pole equipped with an opening/closing mechanism, the main fixed conductor 3 is connected to the mold base/
An opening in the bottom wall of! It is attached so that the bottom surface is exposed on b.
A main fixed contact element and an arc runner 5 are added to the upper surface thereof, and the arc fixed contact element B is attached to the arc runner S. A rear connecting terminal conductor is detachably attached to the exposed portion of the bottom surface of the main fixed conductor 3 and is led out in the right angle direction.

A multi-pole protruding from the vicinity of the opening /b in the bottom wall of the mold base / to the back side of the bottom wall so as to be at the same height as the central bottom wall protrusion /C and extending toward the side edge of the insulator case. A groove wall /d forming a groove that partitions the groove is integrally formed. This is due to the specifications of the main fixed conductor 3 as shown in Figure 3.
Remove the back side connecting terminal conductor, and attach the front side connecting terminal conductor g to the exposed part of the main fixed conductor 3 along the back side of the bottom wall so that it fits in the groove wall /C that partitions the multipole, and insulate the other end. It is made replaceable so that it protrudes from the side edge of the object case.

A main movable contact // corresponding to the main fixed contact DA and an arc movable contact /2 corresponding to the arc fixed contact +6 are provided at one end of the movable contact preliminary 10 of the movable contact device 9, and the other The end is connected to the fixed conductor /q via the flexible conductor /3. In addition, the movable contact holder 10 is integrally attached to the contact holder/S by means of a bottle/B, and this contact holder 15 is pivotally supported by a contact holder shaft/g supported on a fixed frame/R. By rotating the insulating crossbar /q that connects the multi-pole contact boulders 15 so as to operate as one, all the movable contact previews 10 are operated to the open/close position by the open/close operation mechanism via the contact holder/S. . If the rated current carrying capacity increases as in the illustrated embodiment, the movable contact preliminary 10 can be changed to a movable contact preliminary 10F3. equipped with a main movable contact // according to the current. ，
10b may be divided and provided in parallel with the movable contact preview 10.

The current transformer penetrating fixed conductor 20 is overlapped and connected to the upper surface of the fixed conductor /ll-, and the terminal fixed conductor 2/ is connected to the lower surface of the current transformer penetrating fixed conductor 0 by contacting with the lower surface of the current transformer penetrating fixed conductor 0. A connecting terminal conductor is detachably attached thereto, and the back connecting terminal conductor is led out so as to protrude from the bottom wall in a perpendicular direction. According to the specifications, the back side connecting terminal t' and the terminal fixed conductor 20 are removed, and as shown in Fig. 3, one end of the front side connecting terminal conductor 2- is connected to the current transformer penetrating fixed conductor 201, and the other end is connected to an insulator. It can be replaced so that it protrudes from the side edge of the case.

An operating handle 23 made of an insulating material as an opening/closing operation mechanism is attached integrally with an opening/closing lever 25 rotatably supported on a shaft 2 fixed to a molded base of an insulating case, and its tip is attached to a molded base. It protrudes from cover 2.

Toggle link 2 B is another toggle link Koku and bottle: 1g
It is also connected via a trip lever 29, which rotates about a fixed shaft 9A, via a pin 30. On the τ side, the toggle link λ7 is connected to the contact holder/S via the pin 27A. Open/close lever 2
An operating spring 3/ is installed between the lever and the toggle link connecting bin 2g. A contact spring 32 (J
, 2a, 32b) are provided, and the multi-pole contact boulder 1 can be opened and closed by opening and closing the operation handle 23.
5 to the open/close position simultaneously using the contact holder shaft/g as a fulcrum. The arc extinguishing chamber 33 is divided to accommodate the arc extinguishing device 3V, and the insulator case at the end is provided with an exhaust port 35, and the arc extinguishing device 3V has an arc extinguishing grid made of a magnetic plate. F& are arranged at intervals so that the arc movable contact 2 moves and hangs within the notch groove of the arc extinguishing grid.

The inert hook 36, which is a part of the tripping mechanism together with the tripperco 9, is provided in the trip unit case 3g that accommodates a thermal and electromagnetic automatic tripping overcurrent response device via a secondary hook 37. The locking claw of the tripper 39. and releasably engage to form a releasable device. The trip unit case 3 is made of an insulator that can be divided into two parts, and the overcurrent response device includes a tripper 39 having lζ locking claws 39, a thermal bimetal tag,
It is composed of a current transformer 12, an instantaneous tripping type magnet 3, and an instantaneous tripping Rondo KF.

As for the other electrodes which do not have an opening/closing operation mechanism, as shown in Fig. 3 and Fig. A fixed contact device consisting of a main fixed conductor 3 and an arc runner S on which a sub-contact pin and an arc fixed contact B are attached, a movable contact preliminary 10 equipped with a main movable contact// and an arc movable contact/2 are integrated. A movable contact device consisting of a supporting contact holder/S and an arc extinguishing device 33 are provided. The crossbar/q is attached to the central pole contact holder/S that is operated by an opening/closing operation mechanism, and is extended through various different polarity insulating partitions/a to be used as a contact holder for poles that do not have an opening/closing mechanism. The various movable contact guides 10 are integrally connected to the upper end of the movable contact guide 15, and are integrally rotated to the open/close position by an open/close operation mechanism provided at the center pole. When the movable contact device is in the open or closed state, a large space S is formed between the back side of the movable contact device in the component storage chamber and the insulator case. A movable arc gas stopper member 5 is attached to the back surface of the contact hole holder/S of the movable contact device so as to partition this space S from the arc extinguishing chamber side. The movable arc gas restraining members v and r are wide restraining plates that have one arcuate surface substantially centered on the contact holder axis/g and extend in the direction of movement when the circuit is opened in the storage compartment of the insulator case. .

The movable arc gas stopper ring 5 has an opposing surface having a radius X larger than one arcuate surface, substantially concentric with the arc, and protruding inward from the inner wall surface of the mold cover Ω of the insulator case. A fixed arc gas suppressing member ≠6 is provided, and as shown in FIG. ,
As shown in FIG. 7, even when the circuit breaker is closed, the movable and fixed arc gas suppressing members 'IS, '14 are formed so that part of their arc surfaces face each other, and the movable contact device The space S on the back side and the space on the arc extinguishing chamber side are shielded to prevent backflow of arc gas. If a horizontal groove is provided on the opposing surface of the fixed side arc gas suppressing member 'IA', movable and fixed arc gas suppressing members'1. It is preferable to provide the lateral groove Z4 because the airflow passing through the gap between the facing surfaces of t and '14 becomes turbulent and increases fluid resistance, making it more effective to prevent the arc gas from flowing backwards.

As described above, this invention forms a shielding partition between the space S formed on the back surface of the movable contact device and the arc extinguishing chamber side space by the movable arc gas suppression member lI5 and the fixed arc gas suppression member tIB. This has the effect of preventing arc gas generated at the time of shutoff from flowing back into the space S on the back side of the movable contactor device, preventing a drop in the internal pressure of the arc extinguishing chamber, and improving the shutoff performance.

In a circuit breaker with a relatively large rated current carrying capacity, it is effective not only to improve the performance of interrupting large currents, but also to improve the interrupting performance of small currents, which have relatively poor interrupting performance compared to small circuit breakers. It is something. Moreover, it is possible to prevent damage to accessories installed in the space on the back side of the movable contact device and a decrease in interelectrode dielectric strength.

In addition, as an embodiment of the present invention, a central pole equipped with an opening/closing operation mechanism is shown without a shielding partition.
This is difficult to install due to space constraints.11 The opening/closing mechanism has a relatively large fluid resistance and has the function of blocking arc gas, and it is relatively space-saving without the opening/closing mechanism.
Although the objective could be achieved by implementing only the other pole with a larger value, it is of course preferable to similarly provide a shielding partition on the pole provided with the opening/closing operation mechanism.

[Brief explanation of the drawing]

Fig. 1 is a plan view with a part of the insulating cover cut away of a three-pole circuit breaker showing an embodiment of the present invention, and Fig. Ω is a 1-1' of Fig. 1 of the central pole equipped with an opening/closing operation mechanism. 3 is a sectional view showing a closed circuit state at the line nn' of FIG. 1 of a pole without an opening/closing mechanism, and FIG. It is a main part sectional view showing a state. In the figure, l: mold base 1.2: mold force bar, 3: main fixed conductor, g: main fixed contact, 5: arc runner, O: arc fixed contact, 9: movable contact device, //: Main movable contact, /uniarc movable contact, /S
: Contact holder, /q: Crossbar, 3: Operation handle, 25: Opening/closing lever, 2 Ni dokuru link, 2q = trip lever, 33: Arc extinguishing chamber, 3 tick arc extinguishing device, 3 O: Main hook, 37: Secondary hook, 3q nitrite tube bar, ri/: thermal bimetal, ttx: current transformer, t
1J: Electromagnet, 1I: Instantaneous displacement rod, ps, ψO: Arc gas control member, S: Space. Patent applicant: Terasaki Electric Industry Co., Ltd.

Claims (1)

[Scope of Claims] / A movable contact device comprising at least a pair of contacts that can be opened and closed in relation to each name, a movable contact holder and a contact holder to which one of the contacts is attached;
A crossbar that integrally interlocks the multi-pole movable contact device.
, an opening/closing operation mechanism for opening and closing the multi-pole movable contact device, and a releasable device operatively connected to the opening/closing operation mechanism in response to an overcurrent. In a circuit breaker housed in an insulating case, an arc extinguishing chamber having an arc extinguishing device and an exhaust port corresponding to the pair of contacts is provided in a compartment partitioned by name of the insulating case. is formed, and includes a circular or arc-shaped surface that is attached to a contact boulder of the movable contact device that rotates around a fixed axis within a compartment divided into each name mark when opening and closing,
and a wide movable arc gas suppressing member extending in the direction of movement when the circuit is opened, and a fixed fixed member formed on the inner circumferential wall of the insulator case so as to extend inward and having a surface facing the circular arc surface of the movable arc gas suppressing member. A circuit breaker in which a shielding partition is provided between a space formed on the back side of a movable contact device by an arc gas suppressing member and a space on the arc extinguishing chamber side. The circuit breaker according to claim 1, wherein the fixed arc gas restraining member is provided with a lateral groove.