JP4259292B2 - Circuit breaker - Google Patents

Description

  The present invention relates to a circuit breaker applied to overcurrent protection and ground fault protection for a low piezoelectric circuit, such as a circuit breaker for wiring, a leakage breaker, and the like. Related to insulation structure.

For the circuit breakers and earth leakage circuit breakers listed above, the rated sensitivity current and operation time are switched in the earth leakage circuit breaker, for example, so that the user can selectively change the circuit breaker characteristics according to the intended use. Equipped with a manual changeover switch.
Next, a conventional circuit breaker structure equipped with a changeover switch for switching the setting of the sensitivity current and the operating time is shown in FIGS. In the figure, 1 is a circuit breaker case (molded case) comprising a lower case 1a, an upper cover 1b, and an auxiliary cover 1c attached to the upper cover 1b, 2 is a main circuit terminal, 3 is an opening / closing operation handle, 1 of the auxiliary cover 1c is arranged in a trip coil unit (an electromagnetic solenoid that trips a switching mechanism (not shown) of a main circuit contact in response to a leakage detection signal) 4 and is arranged for the sensitivity current and operating time of the circuit breaker. Changeover switches 5 and 6 are installed.

These change-over switches 5 and 6 are slide switches, and as shown in FIGS. 7 and 8, a flexible board 7 for internal wiring (wiring board for connection to an electronic control circuit (leakage detection circuit) not shown). After being mounted and connected to the top of the trip coil unit 4, it is disposed on the upper side of the trip coil unit 4 together with the flexible substrate 7.
Further, in order to manually switch the changeover switches 5 and 6 from the outside of the circuit breaker case 1, an operation window hole 1d corresponding to the changeover switches 5 and 6 is opened in the auxiliary cover 1c shown in FIG. deep. On the other hand, the changeover switches 5 and 6 are covered with a switch cover (resin molded product) 8 having an operation knob which also serves as a dustproof cover for the window hole 1d and connected to the switch knobs 5a and 6a (the back side of the switch cover 8). After forming a recess (just below the operation knob) and fitting it to the knob of the switch, the operation knob 8a protruding from the upper surface side of the switch cover 8 is connected to the operation window hole. It is arranged facing 1d (see, for example, Patent Document 1).
When changing the setting of the operating characteristics (sensitivity current, operating time) of the earth leakage breaker, the operation knob 8a of the switch cover 8 exposed in the operation window hole 1d is manually moved.
JP 2002-208341 A

In recent years, with regard to circuit breakers for wiring and earth leakage circuit breakers, there has been a tendency for safety required for circuit breakers to be strengthened from the viewpoint of electric shock prevention. It is specified to increase the insulation (insulation creepage distance) to more than twice the basic insulation. By the way, an example of the insulation defined in the latest standard is expressed by numerical values. When the rated impulse withstand voltage (Uimp) is 6 kV, the pollution degree is 3, and the rated voltage is 400 V, the space insulation distance is 8 mm, and the creeping insulation distance is 12. It is determined to ensure 6mm or more.
Considering the change-over switches 5 and 6 from this point of view, the change-over switch is an electronic control circuit having a voltage of about several tens of volts (the electronic control circuit is supplied with power supplied by stepping down the interphase voltage of the main circuit via the power supply circuit. In general, there is no risk of electric shock, but if an unexpected trouble such as a short circuit of the power supply circuit of the electronic control circuit occurs during use, the main circuit is connected to the changeover switches 5 and 6. There is a possibility that a voltage (for example, 400 V) is directly applied.

For this reason, the switch cover 8 incorporated in the circuit breaker case 1 in combination with the changeover switches 5 and 6 is also provided between the main body of the changeover switches 5 and 6 and the operation knob 8a of the switch cover 8 that is directly operated by a person. It is necessary to ensure the space insulation distance and creepage insulation distance specified in the standard. In this case, as a means for increasing the insulation distance, the protrusion-like operation knob 8a provided on the switch cover 8 is simply lengthened (increased in height) to increase the insulation distance from the operation end face. Can be considered. However, if the operation knob 8a of the switch cover 8 is extended long upward without changing the assembly structure in which the changeover switches 5 and 6 are arranged on the trip coil unit 4 as shown in FIG. 7, the auxiliary cover 1c of the circuit breaker case 1 is extended. It is necessary to change the operation window hole 1d opened in accordance with the height of the operation knob 8a. As a result, the height dimension of the circuit breaker case 1 increases and the circuit breaker becomes large.

  The present invention has been made in view of the above points, and without changing the breaker case and the assembly structure and layout inside the case, the switch cover operating portion of the switch for switching the breaking characteristic mounted on the circuit breaker is provided. An object of the present invention is to provide an improved circuit breaker that secures a required insulation distance and enhances safety.

In order to achieve the above-mentioned object, according to the present invention, a changeover switch for switching the breaking operation characteristic according to the use application of the circuit breaker is mounted, and connected to a knob of the changeover switch, a resin molding is formed on the switch body. Cover the switch cover with the operation knob that will be the product, and then turn the switch knob manually so that the operation knob of the switch cover faces the operation window hole opened in the cover of the circuit breaker case. In the vessel
After having extended end of the switch cover to the side, the operation knob at a position apart from the change-over switch on its cover extension portion is provided, arranged said changeover switch and extension of the switch cover in the circuit breaker case A guide rail is formed on the case surface of the unit, and the extension portion of the switch cover is guided and supported in the switch switching operation direction along the guide rail. Item 1 ).

With the changeover switch as a slide switch, the switch is connected to a wiring board that communicates with the electronic control circuit, and the switch cover that covers the slide switch is formed into a plane L shape, and an operation knob is provided at the tip of the extension part. The slide switch is arranged on a trip coil unit arranged in a circuit breaker case, and a convex guide rail parallel to the slide switch is formed on the surface of the trip coil unit, and the switch cover is provided on the guide rail. It was formed on the extended portion back surface grooves fitted slidably guided support the switching operation direction of the switch (claim 2).

According to the above configuration, the operation knob of the switch cover over the changeover switch is provided on the cover extension that extends laterally (on the same surface) from the end of the switch cover and is separated from the switch body. Thus, a required insulation creepage distance regulated by the standard can be ensured between the operation knob and the changeover switch body. Moreover, with an assembly structure in which each part is incorporated in the same layout as the conventional circuit breaker case with the same external dimensions as conventional products, the switch cover operation knob faces the operation window hole opened in the circuit breaker case cover, In this state, the changeover switch can be safely switched by manual operation from outside without fear of electric shock.
In this case, the switch cover extension is guided and supported in the direction of the switching operation of the switch along the guide rail formed on the surface of the case (insulator) of the trip coil unit, for example, in another circuit breaker case. As a result, the switch switching operation can be performed stably and smoothly.

Embodiments of the present invention will be described below based on the examples shown in FIGS. In addition, in the figure of an Example, the same code | symbol is attached | subjected to the member corresponding to FIGS. 5-8, and the description is abbreviate | omitted.
The circuit breaker (leakage breaker) of the illustrated embodiment is basically the same assembly structure as the conventional product shown in FIGS. 4 to 8, and the rated sensitivity current and operating time of the leakage breaker are used. Slide switches are used as the change-over switches 5 and 6 for switching according to the application, and each switch is arranged on the flexible substrate 7 in a straight line and mounted and connected to the trip coil unit 4. And incorporated in the circuit breaker case 1.
On the other hand, the switch cover 8 of a resin molded product that is connected to the knobs 5a and 6a of the changeover switches 5 and 6 and is placed on the switch body has the following configuration. That is, the switch cover 8 has an L-shaped planar shape as shown in FIGS. 2 (a) and 2 (b), and its operation knob (a knob portion for holding a finger) 8a extends laterally from the area of the switch body. It is formed so as to protrude from the tip portion of the existing extension portion 8b to the upper surface. In addition, 8c is a recess (recess) formed on the back side of the switch cover 8 so as to be fitted and coupled to the knobs 5a and 6a of the changeover switches 5 and 6, and 8d is a trip coil unit having an extension 8b of the cover as described later. 4 is a guide groove (concave groove) formed on the back side of the operation knob 8a so as to be slidably guided along the guide rail 4a formed on the upper surface of the case 4 (resin case). 6 is formed in a direction parallel to the switching operation direction 6 (the operation direction of the slide switch knob).

On the other hand, in the auxiliary cover 1c (see FIG. 4) of the circuit breaker case 1, the operation knobs 8a of the switch cover 8 and the corresponding operation window holes 1d are opened in a line. The assembly of the trip coil unit 4, the changeover switches 5, 6, the flexible substrate 7 and the switch cover 8 shown in FIG. The operation knob 8a of the switch cover 8 is disposed so as to face.
The changeover operation of the changeover switches 5 and 6 with the above configuration is the same as that of the conventional product, and the operation knob 8a of the switch cover 8 facing the operation window hole 1d opened in the auxiliary cover 1c of the circuit breaker case 1 is moved with the fingertip. By doing so, the sensitivity current and operating time of the circuit breaker can be switched. In addition, since the operation knob 8a is located away from the main bodies of the changeover switches 5 and 6 and a required insulation distance is secured between them, for example, the changeover switch is based on an accident occurring in the electronic control circuit. Even if the operation knob 8a of the switch cover 8 is touched with the main circuit voltage applied to the switches 5 and 6 as they are, there is no risk of electric shock and safety can be ensured. In addition, the extension portion 8b of the switch cover 8 extends laterally on the same surface as the cover, so that it can be arranged in a limited height space of the circuit breaker case 1.

  In the illustrated embodiment, the shape of the cover 8 of the changeover switches (slide switches) 5 and 6 is a flat L-shape, and the operation knob 8a is provided at the bent tip, but the cover is moved in the sliding direction of the changeover switch. The same effect can be obtained by simply extending and implementing an operation knob on the extension.

The disassembled perspective view showing the assembly structure of the principal part containing the changeover switch by the Example of this invention FIG. 2 is an enlarged view of the configuration of the switch cover in FIG. The perspective view showing the assembly state of the principal part structure corresponding to FIG. FIG. 3 is an external perspective view of a circuit breaker in a state where the assembly of FIG. 3 is assembled in a breaker case. External perspective view of a conventional circuit breaker The perspective view of the circuit breaker showing the internal structure in the state which removed the auxiliary cover of FIG. FIG. 6 is an external perspective view showing the assembly structure of the main part including the changeover switch in FIG. 7 is an exploded perspective view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Circuit breaker case 4 Trip coil unit 4 Guide rail 5,6 Changeover switch 5a, 6a Knob 7 Flexible board (wiring board)
8 Switch cover 8a Operation knob 8b Cover extension 8d Guide groove

Claims (2)

A changeover switch that switches the breaking operation characteristics according to the intended use of the breaker is installed, and the switch cover is covered with a switch cover with an operation knob connected to the knob of the changeover switch. In the circuit breaker in which the operation switch is manually switched by facing the operation window hole opened in the cover of the circuit breaker case,
After extending one end of the switch cover on the same surface, an operation knob is provided on the cover extension at a position separated from the main body of the changeover switch, and the changeover switch and the extension of the switch cover are provided in the circuit breaker case. And a guide rail is formed on the case surface of the unit, and the extension portion of the switch cover is slidably guided and supported in the switch switching operation direction along the guide rail. circuit breaker, characterized in that the the like. 2. The circuit breaker according to claim 1 , wherein the change-over switch is a slide switch, the switch cover is mounted and connected to a wiring board that leads to the electronic control circuit, and the shape of the switch cover that covers the slide switch is a planar L-shape. As described above, an operation knob is provided at the tip of the extension, and the slide switch is disposed on the trip coil unit disposed in the circuit breaker case, and the trip coil unit has a convex surface parallel to the slide switch. A circuit breaker characterized in that a guide rail of a strip is formed, and a guide groove formed on the back surface of the extension portion of the switch cover is fitted to the guide rail so as to be guided and supported so as to be slidable in the switching operation direction of the switch.

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