JPS6115564Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a simple circuit breaker that is used, for example, in submersible pumps, etc., and automatically cuts off the electrical circuit by detecting overload, short circuit, electric leakage, etc. The purpose of this invention is to simplify the internal structure and wiring work, as well as to make the circuit section more compact, thereby providing a circuit breaker that is smaller overall.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings, which are examples of the present invention.

The drawing shows an earth leakage breaker, which is roughly composed of a base 1, a relay body 24, a circuit section 40, a zero-phase current transformer 52, a case 60, and a terminal cover 81.

The base 1 is integrally molded of synthetic resin, plugs 2, 2 serving as power terminals are insert molded therein, and a stepped portion 3 is provided at the outer peripheral end over the entire circumference. In addition, there are two through holes 4 on the top surface,
5, 6, 7, 8, square holes 9, 9, recesses 10, 11, a barrier 12, and a cylindrical circuit housing part 13 are provided, and inside the housing part 13 there is a groove in the vertical direction. 13a is formed. Load terminals 14 and 17 are each punched out from a single conductive metal plate and bent as appropriate, and are fitted into the recesses 10 and 11 and positioned. Fixed contacts 15, 18 are fixed to one end of the load terminals 14, 17, screw holes 16, 19 are screwed to the other end, and terminal screws 20, 21 are screwed into the screw holes 16, 19. I'm starting to do that.

The relay body 24 includes a yoke 25, a spool 29 around which a coil 28 is wound, an iron core 30 (see FIG. 3), a movable iron piece 31, and an insulating stand 32 on the upper surface of the movable iron piece 31.
Two movable contact pieces 33, 35 fixed via
The protrusion 26 provided at the lower end of the yoke 25 is fitted into the square hole 9 of the base 1 for positioning, and a fixing screw (not shown) is inserted into the through hole 4 from the bottom surface of the base 1. The relay body 24 is fixed on the base 1 by inserting and screwing it into the lower end 27 (see FIG. 3) of the yoke 25. When the relay main body 24 is fixed, the movable contacts 34 provided at the tips of the movable contact pieces 33, 35,
36 is the fixed contact 1 due to the urging force of the return spring 37.
5 and 18.

The circuit section 40 consists of a printed circuit board 41 and a control circuit 42 configured by connecting appropriate electronic components (for example, SCR, etc.) to the printed circuit board 41. It is inserted into the housing section 13 and positioned by the groove 13a provided inside the storage section 13. The circuit section 40 is insulated from the relay main body 24, contacts, etc. when it is housed in the circuit housing section 13. Two pairs of movable pieces 43, 45 and fixed pieces 44, 46 connected to the control circuit 42 are provided at the upper end of the printed circuit board 41.
A reset button 47 and a test button 48 are in contact with the upper surface of the button 45, respectively. Furthermore, an earth leakage indicator lamp 49 made of a light emitting diode is attached to the center of the upper end of the printed circuit board 41.

Since the entire outer peripheral surface of the zero-phase current transformer 52 is coated with synthetic resin, it has a through hole 53 in the center, and a main circuit conductor 54 with one end connected to the plug 2, 2 in the through hole 53, 55 is inserted and wound several times,
The zero-phase current transformer 52 is mounted in a floating state from the upper surface of the base 1 due to the rigidity of the main circuit conductors 54 and 55. The other ends of the main circuit conductors 54 and 55 are connected to the movable contact pieces 33 and 35 of the relay body 24. Terminals 56 of the secondary winding protrude from the upper surface of the zero-phase current transformer 52, and these terminals are connected to the control circuit 42 by lead wires (not shown).

The case 60 is integrally molded from synthetic resin, and has a recess 62 on the top surface for mounting a nameplate 61 (see Figure 3), and this recess 62 has three holes 63, 64, and 65. It is provided. Above hole 6
A reset button 47 and a test button 48 protrude from holes 3 and 64, respectively, and another hole 65 corresponds to an earth leakage indicator lamp 49. Large diameter recesses 6 are provided around the holes 63, 64, and 65.
6, 67, and 68 are provided, and by fitting caps 69, 70 and transparent plate 71 made of rubber into these recesses, and pressing the name plate 61 from above, the upper surface of the case 60 is sealed. It becomes a structure. A presser piece 72 is integrally provided at one end of the case 60, and the outline of the case 60 including this presser piece 72 is the same as that of the base 1.
The case 60 and the base 1 are integrated by pressing them onto the upper surface of the base 1 through the screws and screwing fixing screws (not shown) into the case 60 from the lower surface of the base 1 through the through holes 5 and 6. be done. The lower surface of the holding piece 72 presses the load terminals 14 and 17 when the case 60 and the base 1 are integrated, thereby preventing the load terminals from wobbling. Two exposure holes 73 and 74 are provided in the holding piece 72, and the load terminals 14 and 1 are connected through the holes 73 and 74.
7 and terminal screws 20, 21 are exposed.

The terminal cover 81 is box-shaped with an open bottom and is integrally molded from synthetic resin. A conduit 82 made of a rubber material is fitted into the terminal cover 81, and a cord 83 connected to a load such as a submersible pump passes through the conduit 82 and connects the load terminals 14, 17 exposed from the holding piece 72.
connected to. Then, the terminal cover 81 is crimped onto the holding piece 72 with the packing 80 in between, and a fixing screw (not shown) is inserted from the bottom surface of the base 1 through the through holes 7 and 8 of the base 1 and through the holding piece 72. By screwing the terminal cover 81 through the holes 75 and 76, the terminal cover 81 is fixed onto the presser piece 72.

In the assembled state as described above, the inside of the earth leakage breaker is sealed by the case 60, the base 1, and the packing 59, making it waterproof, and the terminal part is made up of the terminal cover 81, the holding piece 72, the packing 80, and the packing 59. It is sealed with a conduit 82. Therefore, even if the earth leakage breaker is installed near the submersible pump, there is no fear that water droplets will enter the earth leakage breaker.

Here, the operation of the earth leakage breaker will be explained.

First, the plug 2 is inserted into an outlet, and one end of the cord 83 is connected to a load such as a submersible pump. In this state, the movable contact 3 of the relay body 24
4 and 36 are in contact with fixed contacts 15 and 18,
The load circuit is in the on state.

Next, when a leakage occurs in the load, the zero-phase current transformer 5
2 through the control circuit 42
is excited, and the movable iron piece 31 is attracted to the iron core 30 and rotates clockwise in FIG. As a result, the movable contacts 34, 36 are separated from the fixed contacts 15, 18, the main circuit is cut off, and power supply to the load is stopped. At the same time, the leakage indicator lamp 49 lights up to indicate that a leakage has occurred. When interrupting a large current, there is a risk that an arc will occur and an arc short circuit will occur between the contacts of each pole. Since it separates the contacts, insulation is ensured and there is no need to worry about arc short circuits.

Even after the main circuit is cut off, the coil 28 is kept in an excited state by the action of the control circuit 42, and the movable iron piece 31 continues to be attracted to the iron core 30. and,
When resetting the load after repairing the earth leakage point, press the cap 69 of the reset button 47 protruding from the front of the case 60, bend the movable piece 43 attached to the printed circuit board 41, and release the fixed piece 44. bring into contact with. As a result, the control circuit 42
is released, the coil 28 is demagnetized, and the movable iron piece 31 is rotated counterclockwise in FIG.
36 and fixed contacts 15 and 18 are closed again, and the load circuit is turned on. Then, the earth leakage indicator lamp 49 is also turned off.

To test the operation of this earth leakage breaker, press the cap 70 of the test button 48,
The coil 28 is excited by bringing the movable piece 45 attached to the printed circuit board 41 into contact with the fixed piece 46 . As a result, the movable contacts 34, 36 and the fixed contacts 15, 1
8 and at the same time, the earth leakage indicator lamp 49 lights up, so that it can be confirmed that the operation has been performed.

As is clear from the above explanation, according to the present invention, the control circuit is provided on the printed circuit board to constitute the circuit section, and this circuit section is housed in the cylindrical circuit storage section provided on the base. It is compact and can be miniaturized as a whole, and can be insulated from the outside. In addition, the contacts for reset and testing, as well as the operation indicator lamp, are integrated into the printed circuit board, and the printed circuit board is positioned in the groove of the circuit storage section, so all you have to do is store the printed circuit board in the circuit storage section. The button and each movable button and the window hole can be made to correspond accurately to the lamp, which facilitates assembly and also simplifies the internal structure and wiring work.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a circuit breaker according to the present invention, FIG. 2 is a plan view with the case and terminal cover removed, and FIG. 3 is a sectional view taken along the line -- in FIG. 2. 1...Base, 2...Plug (power terminal), 1
0, 11...Recess, 13...Circuit storage part, 13a
...Groove, 14, 17...Load terminal, 15, 18...
... Fixed contact, 24 ... Relay body, 25 ... Yoke, 28 ... Coil, 30 ... Iron core, 31 ... Movable iron piece, 33, 35 ... Movable contact piece, 34, 36
...Movable contact, 40...Circuit section, 41...Printed circuit board, 42...Control circuit, 43, 45...Movable piece, 44, 46...Fixed piece, 47...Reset button, 48...Test button , 49...Earth leakage indicator lamp (operation indicator lamp), 52...Zero-phase current transformer, 54, 55...Main circuit conductor, 60...Case, 72...Holding piece part, 81...Terminal cover, 8
2... Conduit.

Claims (1)

[Scope of utility model registration request] A pair of plug-shaped power terminals are protruded from the bottom of the base, a zero-phase current transformer and the relay body are attached to the top of the base, and a cylindrical circuit storage part with a groove on the inside of the top of the base. is integrally protruded, and in this circuit storage part, a printed circuit board on which a control circuit for operating and self-maintaining the relay main body according to the output of the zero-phase current transformer is mounted is mounted so that both edges of the printed circuit board are engaged with the groove. A movable piece and a fixed piece that constitute the reset contact, a movable piece and a fixed piece that constitute the test contact, and an operation indicator lamp are attached to the upper end of the printed circuit board, and the base The upper surface of the case that covers the upper surface is provided with a window hole through which the operation indicator lamp is exposed, and a reset button and a test button that can operate the reset movable piece and the test movable piece, and the power terminal and the relay body can be moved. A circuit breaker characterized in that the contact piece is connected to the contact piece via a zero-phase current transformer, and the secondary winding of the zero-phase current transformer is connected to the control circuit.