JPS6136059Y2 - - Google Patents

Description

[Detailed explanation of the idea] This idea is related to electrical leakage and disconnection.

In general, an earth leakage or disconnection device is constructed by amplifying the current generated on the secondary side of a zero-phase current transformer, which is the earth leakage detection part, and supplying it to a tripping coil, and driving the plunger. Trip is working.
In case of such leakage or disconnection, an interlocking contact that turns off in conjunction with the tripping operation is inserted into the power supply for the current amplification circuit, and when the tripping coil is energized, the power supply circuit is cut off. There are some that allow measurements of insulation. In this case, conventionally, as shown in FIG. 1, a structure has been adopted in which the microswitch B together with the tripping coil A is supported by a switch base C, and the base C is attached to a device stand.

However, this structure simply adds a switch base C and a micro switch B to the device stand, so the number of parts increases for the device as a whole.
The problem was that it took up a lot of space.

Therefore, the purpose of this invention is to provide an earth leakage and disconnection device that can reduce the number of parts and space.

An embodiment of this invention is shown in FIGS. 2 to 8. That is, first, the relay for earth leakage and disconnection is made by integrally molding three protrusions 6 to 8 that form press-fit mounting slits 3 to 5 on the end surface 2 of the tripping coil bobbin 1, and attaching the fixing parts that form the contact parts to these protrusions 6 to 8. The contact plate 9 and the movable contact plate 10 are press-fitted and fixed. In other words, the L-shaped fixed contact plate 9 is inserted into the slits 3 and 5 of the protrusions 6 and 8.
One end of the movable contact plate 10 is press-fitted into the slit 4 of the protrusion 7, and the fixed contact 11 of the fixed contact plate 9 and the movable contact 12 of the movable contact plate 10 are opposed to each other. The plunger 13 is moved by engaging the movable contact plate 10 with the inner surface of the bent tip 14.
A normally closed contact is established by a return spring 15. 16
is the yoke, 17 is the coil, 18 is the lock rod, 19
is a lock release button, which is supported by a return spring 19a. 20 is a lead wire for the amplified earth leakage detection current that is energized to the coil 17, and 21 is a lead wire for the power supply circuit for the amplifier circuit connected to the contact plates 9 and 10.

Figures 6 and 7 show this relay incorporated into an earth leakage or disconnection switch, and Figure 8 shows its control circuit. That is, 22 is a power supply side connection terminal, 23 is a load side connection terminal, 24 is a fixed contact, 25 is a movable contact, 26 is an arc extinguishing grid, 27 is a switchgear with a tripping mechanism, 28 is a tripping operation part thereof, 29 30 is a handle, 30 is a test button, ZCT is a zero-phase current transformer, and an amplifier circuit Amp is built into the block.Relay P has its plunger 14 disposed opposite to the tripping operation part 28.

This leakage or disconnection occurs because there is no leakage current in the normal state, so no current flows to the tripping coil 17 in FIG. 8, the plunger 13 is supported by the return spring 15, and the movable contact 12 is Therefore, since it is in contact with the fixed contact 11, the amplifier circuit
Power is being supplied to the Amp. If there is an electrical leak,
A secondary current is generated in the zero-phase current transformer ZCT, and the amplifier circuit
The magnetic force is amplified by the amplifier, energizes the coil 17, generates magnetic force in the plunger 13, and operates the plunger 13 against the return spring 15. plunger 13
This action pushes the tripping portion 28 of the shearing mechanism (not shown) facing the outer surface of the bent tip 14 of the plunger 13 to cause the circuit to break, and the movable contact 12 to open and separate. The operating state of 13 is locked by a locking rod 18. By pressing button 19, the lock is released and the system returns to normal.

With this configuration, the conventional micro switch and its mounting base are no longer necessary, the number of parts can be reduced, assembly can be simplified and the cost can be reduced, and the movable contact plate 10 and fixed contact plate 9 are replaced by a tripping coil bobbin. 1 and opened and closed by the plunger 13, the space can be significantly reduced. Moreover, both contact plates 9,
If 10 is attached by press-fitting, the attachment work will be extremely simple.

As described above, the earth leakage and disconnection device of this invention includes a zero-phase current transformer, an amplifier circuit that amplifies the output of this zero-phase current transformer, and a switchgear with a tripping mechanism that has a tripping operation part. , a bobbin wound with a coil excited by the output of the amplifier circuit, a plunger with a return spring inserted through the bobbin and actuated by the excitation of the coil to drive the tripping operation part, and one end surface of the bobbin. The number of parts can be reduced compared to the conventional relay because the relay is press-fitted into a protrusion with a slit provided in the relay and is opened by actuation of the plunger and turns off the power to the amplifier circuit. This has the effect of simplifying the structure, reducing the size, and simplifying the work of attaching the contact portion.

[Brief explanation of drawings]

Figure 1 is a perspective view of a conventional tripping coil and micro switch used for leakage and disconnection, Figure 2 is an exploded perspective view of an embodiment of this invention, and Figure 3 is its installed state in normal condition. Fig. 4 is a side view thereof, Fig. 5 is a plan view thereof, Fig. 6 is a partially cutaway plan view of an earth leakage or disconnection circuit to which this relay is applied, and Fig. 7 is a longitudinal sectional view thereof. FIG. 8 is a control circuit diagram for leakage and disconnection. ZCT...Zero-phase current transformer, Amp...Amplification circuit, P
...Relay, 1...Bobbin, 2...End face, 3-5
...Slit, 6-8...Protrusion, 9,10...
A contact plate constituting a contact portion, 13...plunger,
15...Return spring, 17...Coil, 27...Switching device with tripping mechanism, 28...Tripping operation section.

Claims (1)

[Claims for Utility Model Registration] (1) A zero-phase current transformer, an amplifier circuit that amplifies the output of the zero-phase current transformer, a switchgear with a tripping mechanism having a tripping operation part, and the amplifier circuit. a bobbin wound with a coil excited by the output of the bobbin, a plunger with a return spring inserted into the bobbin and actuated by the excitation of the coil to drive the tripping operation part, and a slit provided on one end surface of the bobbin. A relay comprising a contact portion press-fitted into a protruding portion and opened by actuation of the plunger and turns off power to the amplifier circuit. (2) The return spring is interposed between the other end surface of the bobbin and one end of the plunger, a bent part is formed at the other end of the plunger, and the inner surface of the bent part is connected to the contact part. The electric leakage or disconnection device according to claim (1) of the registered utility model, wherein the driving portion is a driving portion and the outer surface thereof is the driving portion of the tripping operation portion.