JP2003141981A - Leakage protection plug - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve operation reliability and realize cost reduction by performing mechanically display of operation of the leakage protection plug by interlocking with the reset button. SOLUTION: The trip display board 20 provided inside the trip display aperture 6 of the cover 2 is contacted to a cam 5e formed on a reset button 5 through a slant face 20c and interlocked with the upward and downward movement of the reset button 5, and the trip display board 20 is depressed to the reset button 5 by a return spring 21. When tripping happens, the reset button 5 is released from the latch and goes up by the repulsive force of a main spring 19 and the trip display board 20 moves to the trip display position by the repulsive force of the return spring 21. Compared with the conventional part of electrical trip display using an auxiliary contact, there is no concern of contact failure of the auxiliary contact, and thereby the operation reliability is high.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth leakage protection plug used for household hot water toilet seats and the like, and more particularly to trip display means for informing the occurrence of trip when the power is cut off due to the occurrence of earth leakage.

[0002]

2. Description of the Related Art As a leakage protection plug, when a reset button is pushed against a main spring from a trip position to a reset position, the reset button is latched at the reset position and the main contact is repulsed by the main spring. When the trip coil is energized and held in the ON state and the leakage detection signal is activated in this state, the latch of the reset button is released and the main contact is turned OFF, and the reset button is pushed to the reset position by the repulsive force of the main spring. Some are pushed back. An indicator lamp including an LED or a neon lamp is generally used for the trip display of the leakage protection plug. This indicator light is turned on / off via an auxiliary contact that works with the main contact.
It is normally turned off, but is turned on when the power is cut off to notify the occurrence of a trip.

[0003]

Such a conventional trip display means requires an auxiliary contact in addition to the main contact. However, in the auxiliary contact circuit whose current value is smaller than that of the main contact, special consideration needs to be given to the contact material and manufacturing process in order to maintain the contact reliability of the auxiliary contact for a long time. Therefore, conventionally, there was a problem that the cost had to be high. Therefore, an object of the present invention is to obtain an inexpensive and highly reliable trip display means for an earth leakage protection plug.

[0004]

In order to solve the above-mentioned problems, according to the present invention, when the reset button is pushed from the trip position to the reset position against the main spring, the reset button is latched in the reset position. At the same time, the main contact is O due to the repulsive force of the main spring.
When the trip coil is energized and held in the N state and the trip coil is energized by the leakage detection signal in this state, the latch is released and the main contact is turned off, and the reset button is reset by the repulsive force of the main spring. In the earth leakage protection plug pushed back to the position, a display window is provided near the reset button, and a display plate that slides in conjunction with the reset button is provided inside the display window (claim 1).

According to claim 1, when a trip occurs,
Focusing on the point that the reset button is released from the latch and pushed back from the reset position to the trip position, the up / down movement of the reset button is used to mechanically display the operation. It is possible to display a trip without using it.

[0006] In the present invention, the display plate is pushed by contact between an inclined surface formed on one side of the reset button and the display plate and a cam portion formed on the other side, and the display plate is arranged above the display plate. It is preferable to provide a return spring for pressing the reset button (claim 2). In that case,
The return spring may be formed integrally with the display plate (claim 3).

Further, in claim 1, it is possible that the display plate is made of a flexible plate material and the display plate is connected to the reset button (claim 4).

On the other hand, in any one of claims 1 to 4, the display plate is provided with ON and OFF indications, and the ON display and the OFF display are displayed from the display window at the reset position and the trip position of the reset button. Either by making them look into each other (Claim 5), by displaying different colors of green and red on the display plate, and displaying the green display and red display from the display window at the reset position and trip position of the reset button. It is advisable to let each of them look (claim 6).

The trip display window may be provided with a lens for enlarging the display of the trip display plate or making it visible from the side so as to facilitate visual recognition (claim 7).
This makes it easier to view the trip display board even when the earth leakage protection plug is inserted into an outlet near the floor.

[0010]

1 to 4 show an embodiment of the present invention, FIG. 1 is a longitudinal sectional view of a leakage protection plug in an ON state, FIG. 2 is a longitudinal sectional view of the same in a trip state, and FIG. Similarly, FIG. 4 is a vertical sectional view at the time of reset operation, and FIG. 4 is a perspective view showing the appearance of the leakage protection plug. First, in FIG. 4, the leakage protection plug is integrally formed in an insulating container composed of a case 1 and a cover 2, and a pair of plugs 3 to be inserted into a power outlet (not shown) are arranged on the upper back surface so as to project. A lead wire 4 is connected to a load device (not shown) such as a toilet seat. On the other hand, a reset button 5 covered with waterproof rubber is provided on the front surface of the cover 2, and a trip display window 6 is arranged on the upper right of the reset button 5.
A test button 7 is arranged at the lower right. As will be described later, the reset button 5 is used to turn on the main contact again after the main leakage is detected by the earth leakage protection plug and the main contact is opened to shut off the power (trip). It is for displaying the occurrence of a trip. In addition, the test button 7 is used to generate an electric leak in a simulated manner and confirm the operation of the electric leakage protection plug.

1 to 3, particularly in the ON state of FIG. 1, the energizing path is connected to the plug 3 → the movable plate spring 8 whose one end is connected to the plug 3 → the free end of the movable plate spring 8. Movable contact 9 → fixed contact 10 with which the movable contact 9 contacts → fixed contact base 11 with the fixed contact 10 coupled to one end → a penetrating conductor that rises from the other end of the fixed contact base 11 and penetrates the zero-phase current transformer 12 13 → the printed circuit board 14 of the leakage detection circuit to which the tip of the through conductor 13 is connected → the lead wire 4 connected to the printed circuit board 14 in this order. Needless to say, these energizing paths are provided adjacent to each other. Now, a crossbar 15 made of an insulating material is in contact with the lower surface of the movable leaf spring 8 in FIG. 1, and the crossbar 15 is guided by the case 1 so as to be slidable in the vertical direction in FIG. The crossbar 15 has arms 15b on the left and right of a block-shaped body 15a.
Is projected, the arm 15b contacts the movable leaf spring 8, and the main body 15a is in sliding contact with the case 1.

An actuator 16 made of a thin plate is slidably inserted in the crossbar 15 in the left and right directions in FIG. 1, and the right end of the actuator 16 is engaged with a plunger 17a of a trip coil 17 so as to be vertically slidable. A compression coil spring 18 inserted between the left end and the case 1 urges it to the left in FIG. On the other hand, the main body 15a of the crossbar 15 is hollow in the vertical direction, and the actuator 16 faces the hollow portion.
Although not shown in the drawing, a square engaging hole is formed. The reset button 5, which is held on the cover 2 so that it can be pressed down,
It is a mushroom shape having a shaft portion 5a and is urged upward in FIG. 1 by a main spring 19 which is a compression coil spring.
In the trip state shown in FIG. 2, it is locked in place by the claw 5b. Further, in FIG. 2, the shaft portion 5 of the reset button 5 is
A hook 5d is formed at the tip of a by a notch 5c. Reference numeral 25 is a rubber waterproof cover.

Inside the portion of the cover 2 where the trip display window 6 is provided, a trip display plate 20 is slidably guided and held in the left-right direction in FIG. The trip display plate 20 includes a display portion 20a along the cover 2 and an operation portion 20b extending in a letter-shape toward the reset button 5. The trip display plate 20 is biased to the left in FIG. 1 by a return spring 21 formed of a compression coil spring inserted between the trip display plate 20 and the cover 2, and is integrally formed with the reset button 5 in the ON state of FIG. It hits the cam portion 5e. Here, although not shown, on the upper surface of the display unit 20a, green and red color-coded displays are provided on the left and right in FIG. 1, and the green display is visible through the trip display window 6 in the ON state of FIG.

In such an earth leakage protection plug, as shown in FIG.
In the ON state of, the reset button 5 is latched at the reset position in FIG. 2 against the main spring 19. In this state, the reset button 5 has the shaft portion 15a.
Has entered the hollow portion of the crossbar 15 and is engaged with the engagement hole of the actuator 16 via the hook 5d. Therefore, the actuator 16 receives the repulsive force of the main spring 19 via the reset button 5, and this repulsive force is transmitted to the movable leaf spring 8 via the crossbar 5,
The movable leaf spring 8 is lifted upward to bring the movable contact 9 into contact with the fixed contact 10.

Now, when a leakage occurs, an output is generated in the zero-phase current transformer 12, and this output is amplified by the leakage detection circuit mounted on the printed board 14 and added to the trip coil 17. As a result, the trip coil 17 is moved to the plunger 17
a is attracted, and the actuator 16 is slid rightward in FIG. 1 against the compression coil spring 18. As a result, the reset button 5 and the actuator 16 are disengaged,
The movable leaf spring 8 moves downward together with the crossbar 15 and the actuator 16 by its own repulsive force, and separates the movable contact 9 from the fixed contact 11. This turns off the main contact
However, the exciting current is also cut off in the trip coil 17 which is supplied with power from the load side of the main contact. On the other hand, the reset button 5 which is released from the latch is
It is pushed up by the repulsive force of and is locked at the trip position by the claw 5b. At the same time, the trip display plate 20, which had hit the cam portion 5e of the reset button 5 until then, is pushed to the left by the repulsive force of the return spring 21 to stop, and the red display of the display portion 20a can be seen through the trip display window 6a. At the same time, the inclined surface 20c of the operation portion 20b faces the cam portion 5e of the reset button 5. FIG. 2 shows this trip state.

In order to reset the leakage protection plug from the trip state shown in FIG. 2, the reset button 5 is pushed down against the main spring 19 with a finger as shown in FIG. The pushed down reset button 5 hits the actuator 16 through the hollow portion of the crossbar 15, pushes the actuator 16 rightward in FIG. 3 by the inclined surface of the tip of the hook 5d, and still advances. As a result, the actuator 16 that has passed over the hook 5d receives the compression coil spring 18
By the repulsive force of, it falls into the notch 5c (FIG. 2) of the reset button 5 and engages with the hook 5d. When you release your finger, the main spring 19 lifts the movable leaf spring 8,
The ON state of FIG. 1 is entered. On the other hand, the trip display plate 20 is pushed rightward by the cam portion 5e of the reset button 5 to the position shown in FIG. 1 through the inclined surface 20c of the operation portion 20b, and the green display can be seen through the trip display window 6.

FIG. 5 shows a different embodiment of the present invention. In this embodiment, the trip display plate 20 is made of an elastic resin material, and a return spring 21 formed of a serpentine leaf spring is formed integrally with the trip display plate 20. As a result, the number of parts is reduced and the cost is reduced. Other configurations are the same as those in FIG.

FIG. 6 shows a further different embodiment of the present invention. In this embodiment, the trip display plate 20 is made of a flexible resin material such as vinyl chloride and is connected to the reset button 5 via a shaft 22 at the left end of FIG. The trip display plate 20 is bent while the reset button 5 is moved up and down, and is covered by the cover 2
It goes in and out of the groove 23 and switches the display. According to this embodiment, the return spring 21 is unnecessary and the number of parts is reduced. Other configurations are the same as those in FIG.

FIG. 7 shows a further different embodiment of the present invention. In this embodiment, the trip display window 6 is provided with a lens 24 that helps the trip display plate 20 to be visually recognized. The lens 24 has a function of enlarging the ON / OFF display or the color-coded display of the trip display board 20 or making it visible from the side. By the way, since the earth leakage protection plug is inserted into an outlet near the floor surface, the trip display window 6 is often difficult to see, and the trip display plate 20 can be easily viewed by mounting the lens 24. Other configurations are the same as those in FIG.

[0020]

As described above, according to the present invention, the operation display is mechanically performed by utilizing the vertical movement of the reset button, so that an inexpensive and highly reliable trip display can be performed without using auxiliary contacts. Can be realized.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a leakage protection plug in an ON state showing an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of the leakage protection plug of FIG. 1 in a tripped state.

FIG. 3 is a vertical cross-sectional view showing a reset operation of the earth leakage protection plug of FIG.

FIG. 4 is a perspective view showing an external appearance of the leakage protection plug of FIG.

FIG. 5 is a vertical cross-sectional view of a leakage protection plug in a tripped state showing another embodiment of the present invention.

FIG. 6 is a vertical cross-sectional view of a leakage protection plug in a tripped state showing a still another embodiment of the present invention.

FIG. 7 is a vertical cross-sectional view of a leakage protection plug in a tripped state showing still another embodiment of the present invention.

[Explanation of symbols]

1 case 2 cover 3 plugs 4 lead wire 5 Reset button 5e Cam part 6 Trip display window 8 Movable leaf spring 9 movable contacts 10 fixed contacts 12 Zero-phase current transformer 17 Trip coil 19 main spring 20 Trip display board 20c slope 21 Return spring 24 lenses

Claims (7)

[Claims] 1. When the reset button is pushed from the trip position to the reset position against the main spring,
The reset button is latched at the reset position, and the main contact is turned on and held in the ON state by the repulsive force of the main spring. In this state, when the trip coil is biased by the leakage detection signal, the latch is released. In the earth leakage protection plug in which the main contact is turned off and the reset button is pushed back to the trip position by the repulsive force of the main spring, a trip display window is provided near the reset button, and inside the display window. A leakage protection plug comprising a trip display plate that slides in conjunction with the reset button. 2. The trip display plate is pushed by contact between an inclined surface formed on one side of the reset button and the trip display plate and a cam portion formed on the other side, and the trip display plate is formed by the aforesaid operation. 2. A return spring for pressing the reset button side is provided.
The earth leakage protection plug described. 3. The leakage protection plug according to claim 2, wherein the return spring is formed integrally with the trip display plate. 4. The leakage protection plug according to claim 1, wherein the trip display plate is made of a flexible plate material, and the display plate is connected to the reset button. 5. The trip display plate is provided with ON and OFF displays, and the ON display and the OFF display can be seen from the trip display window at the reset position and the trip position of the reset button, respectively. The leakage protection plug according to any one of claims 1 to 4. 6. The trip display plate is provided with different displays of green and red so that the green display and the red display can be seen through the trip display window at the reset position and the trip position of the reset button, respectively. The leakage protection plug according to any one of claims 1 to 4. 7. The leakage protection plug according to claim 1, wherein the trip display window is provided with a lens that helps the trip display plate to be visually recognized.