JPS61140018A - Display unit for wiring 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 Field of the Invention The present invention relates to improvements in display devices for molded circuit breakers.

In general, molded circuit breakers are arranged so as to operate in a single unit or in a plurality of units adjacent to each other. A case of a hardwire circuit breaker or interrupter is provided with a handle that projects from the inside. This handle can be moved to two specific positions and one intermediate position. When an overload occurs in the load circuit connected in series to the molded circuit breaker, the circuit is cut off and the operating handle moves from the closed position to the intermediate position.
Current supply to the load is cut off. Since several of the molded circuit breakers are typically placed together as a group, it is difficult to ascertain which molded case circuit breaker handle or contact interrupted the overload, especially since most This is especially true since many molded circuit breakers are located in basements or similar low-light locations. In addition, even if a molded case circuit breaker is installed in a location with high illumination, it is often difficult to determine which molded case circuit breaker has tripped. Of course, when a circuit is interrupted due to an overload, it is important to find and correct the cause before returning the circuit by moving the operating handle from the special OFF position to the ON position.

U.S. Patent 405 granted to Raul Guim
No. 6816 discloses a molded circuit breaker that includes a light emitting diode that indicates that the molded circuit breaker has tripped.

A circuit containing a resistor connected in series with a light emitting diode is connected in parallel to the main switch 1 of the molded circuit breaker. However, it is known that the patent granted to Guim has difficulties with maximum withstand voltage. These devices must withstand up to 1500 volts to simulate the surge voltages that would occur on the public line or in the testing laboratory. In the disconnected situation, the high voltage appearing across the terminals of the molded circuit breaker is actually applied to the load consisting of the light emitting diode and the voltage drop resistor of the light emitting diode connected in series. The combined impedance of the light emitting diode and the resistor is approximately 25,000 ohms, which is many times greater than the circuit impedance. Therefore, all the surge voltage is applied across this resistor during 1/2 cycle when the light emitting diode is conducting. Thus, there is no heat dissipation from the resistor in the Guim patent because there is essentially no venting or thermally conductive passageway or venting to the interior of the molded circuit breaker. Therefore, resistors with ratings of several watts are used. In addition, it must be long enough to withstand the electric current (i7M degrees) that appears along the length of the resistor.Due to the volume limitations of molded circuit breakers, it must be possible to It is absolutely impossible to arrange a resistor that is perfect for this purpose.Therefore, resistors that are commonly used tend to crack, arc, or both due to high temperatures.

[Purpose of the Invention] The present invention solves the problems in the prior art, and the purpose of the present invention is to solve the problems in the prior art, and to solve the problem of abnormal surges that occur when an overload or a similar situation is created by testing and is shut off. Provided is a light emitting display device for a general molded case circuit breaker that can provide one voltage protection.This circuit has a reactance element such as a capacitor connected in series with a light emitting diode, and this display The circuit is connected in parallel to the main switch of the molded case circuit breaker. When the molded case circuit breaker performs a breaking operation, the movable contacts are moved away from the fixed contacts by a thermal or electromagnetic trip element and disconnected from the load circuit. At the same time as the circuit between the power supply terminals is opened, a circuit containing a capacitor and a light emitting diode is connected in parallel between the tR'1 terminal and the load circuit.At this point, the light emitting diode lights up and multiple circuit breakers are activated. It can be easily confirmed which one of the two has performed the blocking operation.

[Embodiment] A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

1 and 2 show a thermally sensitive molded circuit breaker provided by a case 10 of a suitable insulating material. The cover on the surface of this molded circuit breaker has been removed so that the inside can be seen clearly. The illustrated case and cover are generally produced by molding of insulating plastic, but this is not a critical part of the invention. housing! A handle 14 is provided that extends through a portion of 2.

As shown in FIG. 1, the handle 14 is shown in the off position by a solid line, and the off position is shown by a line. Note that FIG. 2 is a side view showing a state in which the handle 14 is in the blocking position.

There is a fixed contact 1 on the power line connection piece 18 that engages with the 1' bus when the molded circuit breaker is inserted into the distribution board, which is generally located in a dark or poorly illuminated location.
6 is placed. Further, the movable contact 2 ( ) is arranged on the contact driving member 22 .

The tripping arm 24 is in the on position shown in FIG.
It is pivoted on a boss 26 within the case 10 so as to be pivoted between the cutoff positions shown in the figure. One end of the tension spring 2 is connected to the contact drive member 22 so as to move beyond the center point, and the other end is connected to the tension arm 24ζ.

The handle 14, 1, the point driving member 22 and the tension spring 28 form an operating 8N groove with a toggle-like arrangement so as to extend beyond the center point, and are attached to one side of the pivot support 30 as shown in FIG. When the tension spring 28 is placed, it operates to urge the movable contact 20 toward the fixed contact 16. The toggle or center point crossing mechanism is the handle 14.
．． It is composed of a contact drive part 22 and a tension spring 28, and as shown in FIG. 2, when the boss 26 is located at the curved end of the shaft support 30, the movable contact 20 is urged to the open position. . A load terminal connection screw 32 for connecting the molded circuit breaker to a load circuit is disposed within the case 10. The load terminal connecting screw 32 is screwed or bolted into the case 10 at a portion 36 via a bus bar 34.

A flexible conductor 40, typically made of pure copper, electrically connects the contact drive member 22 and the latch member 38.

The latch member 38 is generally a hook-shaped bimetallic thermostatic element having at least two metal layers having different coefficients of thermal expansion and bending as temperature increases. - of the flexible conductor 40
one end is directly connected to one end of the latch member 38 and +1!
! The end is connected to the contact drive member 22 . Further, the bent end of the latch member 38 is connected to the load terminal connecting screw 32 via the bus bar 34.

A light emitting diode 5o is provided in a circuit connected in parallel to a main switch of a molded circuit breaker disposed between the power line connection piece 18 and the load terminal connection screw 32. Insulated wire 42
is connected to one end of the back side of the power line connection piece 18, and the other end is connected to the current limiting capacitor 44. The current limiting capacitor 44 is connected to one end 48 of the light emitting diode 50 via a conductive wire 46. The light emitting diode F' 50 is embedded in the housing 12 through a hole and is exposed on the surface. One end of the light emitting diode 5o is connected to a conductor 52 to an arm 54 on which a contact 56 is provided. Contact 56 electrically connects trip arm 24 when arm 54 is in the upright position shown at 24' as shown in FIG. , the contact drive member 22 has a portion 22
’ flows. Current then flows from the contact drive member 22 through the flexible conductor 40 and the latch member 38 to the load terminal connection screw 32 to which the load is connected.

Conventional molded circuit breakers are known to open and close in a known manner and to operate to trip under overload. Although the molded circuit breaker itself is important to the present invention, a general one having the structure shown in US Pat. No. 39,302 No. 1 is used. For example, a hook-like member having an end formed on the latch member 38 operates to hold the tripping arm 24 away from the contact 56. However, it is likely to become overloaded.
1If5 +$ 38 hl l< 49 )I=
17) Is: if C=°”C9L”1 bent contact 56
The tripping arm 24 connecting the is released.

FIGS. 5 and 6 are circuit diagrams showing the operation of an electromagnetic type molded case circuit breaker which is similar in many parts to the molded case circuit breaker shown in FIGS. 1 to IK4.

In FIGS. 5 and 6, the same reference numbers as those shown in FIGS. 1 to 4 are given to parts having similar functions. Here, an armature 60 that is deployed via an electromagnetic coil 62 is pivotally supported. This armature 60 and electromagnetic coil 62 are substituted for the tripping arm 24 and latch member 3 shown in FIGS. 1 to 4. Armature 60 electrically connects contact drive member 22 to contact 64 after the load circuit is interrupted. Armature 60 forms a circuit connected from light emitting diode 50 to conductor 52 . When an overload is detected, armature 60
releases the contact drive member 22 from the fixed contact 16, and! As shown in FIG. 6, the contact 64 is moved to a position where it forms a circuit with the contact 56. This movement causes the current limiting capacitor 44. A circuit comprising conductor wire 46 and light emitting diode 50 is connected to a circuit comprising power line connection piece 18 and flexible conductor 40 . Subsequently, the light emitting diode 50 is energized and lights up. Continuity of the circuit is provided by armature 60. Contact drive member 22.
and is formed toward the power supply connection line 66 via the electromagnetic coil 62.

Next, to explain the present invention in detail, the contact drive member 22 is moved by operating the handle 14, and a circuit is connected and opened via the fixed contact 16 and the power line connection piece. In the circuit shown in FIGS. 1-4, when an overload is detected, the tripping arm 24 is moved to the position shown at 24';
A circuit connected from the fixed contact 16 to the movable contact 20 is opened by the movement of the latch portion t38, and the movable contact 20 is opened. Due to this movement, a circuit is formed from the conductor 52 via the arm 54, and the operating handle 14 of the molded circuit breaker
The parallel circuit including the light emitting diode 50 is connected and lights up until it is operated again. Similarly, overload occurs in the 5th and 6th
When detected by the electromagnetic type circuit breaker shown in the figure, the armature 60 is moved by the electromagnetic coil 62, the fixed contact 16 and the movable contact 20 are closed, and the load circuit is interrupted. This movement creates a circuit between contacts 64 and 56 to energize light emitting diode 50, which remains illuminated until handle 14 is actuated to a position that closes the molded circuit breaker.

When used in both the electromagnetic type molded case circuit breakers shown in Figures 5 and 6 and the thermal type molded case circuit breakers shown in Figures 1 to 14, when an overload is detected, the reactance The current-limiting capacitor 44 that limits the t current has an impedance many times higher than the impedance of the load. Therefore, the AC voltage supplied from most h lines is r
? It is applied in parallel to the display circuit provided by a four-way capacitor 44. Since a circuit that does not use current limiting capacitor 44 and a resistor is used as a current limiting device, problems caused by heat do not occur as well. Additionally, special capacitors with high breakdown voltages, such as ceramic capacitors, are available.

It is clear that many modifications can be made to the present invention in addition to those described above without departing from the spirit of the invention. The display circuit connected in parallel is not limited to the above-mentioned molded case circuit breaker.
* '-' * ('l' e IT O[ii! m
It is clear that "l 0u ", i can be applied. In addition, although the present invention has been illustrated using a light emitting diode as the display means of the display circuit, liquid crystal or electrophoretic display means may be used. Furthermore, although the present invention has been described with respect to a single molded case circuit breaker, it is also possible to connect a plurality of adjacent molded case circuit breakers and provide a display device on each of the molded case circuit breakers that are integrally configured. considered as the scope of the present invention.

[Effects of the Invention] In addition to the above, the present invention provides an element that limits the current by reactance in series with the display element, and connects this circuit in parallel between the contacts at the time of interruption, so that high This has the effect that the display circuit of the molded circuit breaker can be turned on without any problem in response even when voltage is applied.

[Brief explanation of drawings]

Fig. 1 is a side view of a general molded circuit breaker that clears the display circuit according to the present invention, and Fig. 2 is a side view of a general molded case circuit breaker equipped with the display circuit according to the present invention, showing the state after the circuit is shut off. , 3rd
Figure 4 is a circuit diagram of the molded case circuit breaker shown in Figure 2 in both the on and off positions; Figure 5 is a circuit diagram of the molded case circuit breaker shown in Figure 2 in both the on and off positions. FIG. 6 is a circuit diagram of the electromagnetic molded case circuit breaker shown in FIG. 5 after the circuit breaker has been disconnected. Code explanation

Claims (1)

[Claims] 1. A first fixed contact connected to an input terminal;
a movable contact mounted on a contact arm movable between a closed position in direct contact with the fixed contact of the contact arm and an open position remote from the first fixed contact; Detecting the presence of an overload condition of a load terminal that is connected to a load via a movable contact and is disconnected from the first fixed contact in an operating state due to an overload, and a molded case circuit breaker connected to the load terminal. a second fixed contact, a tripping means for detecting movement of the detection means and connecting to the second fixed contact when the detection means detects an overload condition, and the input a display circuit that is parallel to the terminal and the load terminal, is in series with the second fixed contact and the tripping means, and includes a light emitting element therein;
A display device for a molded circuit breaker, wherein the display circuit includes a reactance current limiting element provided in series with the light emitting element so that the light emitting element operates when an overload is detected. 2. The display device for a molded circuit breaker according to claim 1, wherein the reactance current limiting element is a capacitor. 3. The display device for a molded circuit breaker according to claim 1, wherein the detection means is a thermally energized bimetal element. 4. The display device for a molded circuit breaker according to claim 1, wherein the detection means is electromagnetically energized.