JPS6240342Y2 - - Google Patents

Description

[Detailed description of the invention] This invention accurately regulates the installation position of the zero-phase current transformer used for earth leakage detection in the earth leakage breaker to eliminate variations in the distance to the heat generating part, thereby reducing variations in characteristics. The present invention relates to an earth leakage detection unit of an earth leakage breaker which is designed to reduce the amount of electricity.

As shown in FIG. 1, the earth leakage detection unit of a conventional earth leakage breaker includes a zero-phase current transformer 1 for detecting earth leakage and a sensor circuit board 15 that processes the signal from the current transformer 1.
and a sensor case 11 in which the board 15 is housed, but since the connection between the zero-phase current transformer 1 and the sensor circuit board 15 is made by a lead wire 17 The disadvantage is that the position of the current transformer 1 is not stable, and as shown in Fig. 2, the position of the current transformer 1 relative to the overcurrent detection section made of bimetal 19 when installed in the earth leakage breaker 18 depends on the product. This has the disadvantage that the earth leakage detection level of the earth leakage breaker 18 varies due to the difference in the earth leakage breaker 18, and also prevents the zero-phase current transformer 1 from hitting movable parts such as the contact 21 and the tripping mechanism 20 in the earth leakage breaker 18. Therefore, it is necessary to attach the lead wire 17 of the zero-phase current transformer 1 as shown in A in FIG. 2, which has the drawback of complicating the assembly process.

The present invention was devised to eliminate these drawbacks of the conventional example, and instead of connecting the zero-phase current transformer and the sensor circuit board using the conventional lead wire, a connecting pin is used to connect the two, and both The purpose of this is to maintain a constant positional relationship after assembly to eliminate contact and proximity with other heat-generating parts and moving parts, to stabilize quality and to improve assembly workability.

The structure of the present invention will be described below with reference to the illustrated embodiment. As shown in FIGS. A plurality of connecting pins 5 parallel to the through hole 3 are implanted at the end of the zero-phase current transformer storage case 4 which has a through hole 3 in the center of the recess 2, and the connecting pins 5 are connected at both upper and lower ends. The winding end portion 10 of the zero-phase current transformer 1 is connected to the upper end portion 6 of the connecting pin 5, and the lower end portion of the connecting pin 5 is connected to the winding end portion 10 of the zero-phase current transformer 1. 7 to the bottom surface 1 of the sensor case 11
a first insertion hole 13 opened at two ends, and a second insertion hole opened at the end of the sensor circuit board 15 mounted on the inner bottom surface 14 of the sensor case 11 so as to vertically overlap with the first insertion hole 13; 16 to connect the lower end 7 of the connecting pin 5 to the sensor circuit board 15, and the connecting pin 5 connects the zero-phase current transformer storage case 4 and the sensor case 11 in parallel with each other. It was designed so that Fig. 3 shows the assembled state of the earth leakage detection unit of the present invention, and as shown in the figure, the zero-phase current transformer storage case 4 and the sensor case 11 are connected to each other in parallel with each other by the connecting pin 5. Furthermore, since a through hole 3 is provided in the center of the zero-phase current transformer storage case 4, a conductive wire for detecting earth leakage can be easily inserted. Further, the zero-phase current transformer storage case 4 and the sensor case 11 are mechanically connected by the connecting pin 5, and electrically, the winding ends 10 of the zero-phase current transformer 1 are connected to the respective sensor circuit boards. 15. At this time, in order to easily connect the winding end 10 of the zero-phase current transformer 1 to the connecting pin 5, a recess is provided on the top surface of the zero-phase current transformer storage case 4 into which the winding end 10 is inserted. Article 22
is installed. In order to assemble the zero-phase current transformer 1, first, as shown in FIG. The lower end 7 of the pin 5 is press-fitted into the insertion hole 23 formed at the end of the storage case 4, so that the lower end 7 protrudes toward the lower surface of the storage case 4. Next, attach the lower end 7 to the bottom surface 1 of the sensor case 11.
2 and the sensor circuit board 15 through the first and second insertion holes 13 and 16, and soldering is performed. The connection pin 5 that is not connected to the winding end 10 of the zero-phase current transformer 1 is used to attach a power supply line or the like.

As described above, in the present invention, the zero-phase current transformer is positioned and stored in the current transformer storage case, and the current transformer storage case and the sensor case are mechanically connected by the connection pin. It is said that the position of the zero-phase current transformer in the earth leakage breaker is stable and that it does not come close to or come into contact with heat-generating or moving parts, which causes the earth leakage detection level to fluctuate due to heat. Furthermore, the connection pins used here not only mechanically connect the sensor case and current transformer storage case, but also connect the sensor circuit board and zero-phase current transformer housed in the sensor case. The sensor circuit board is also electrically connected to the sensor case and the sensor circuit board is fixed to the sensor case, which greatly reduces the effort involved in electrical connection and mechanical coupling when assembling the sensor as a unit for earth leakage detection. It has this advantage.

In addition, among the connection pins installed at the end of the zero-phase current transformer, connect the test winding of the zero-phase current transformer to the connection pin that is not used for connection with the zero-phase current transformer to measure the unbalanced current. If a detection test is performed, the practical value will be further improved.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional earth leakage detection unit.
FIG. 2 is a schematic circuit diagram of the same as above, FIG. 3 a is a perspective view of an earth leakage detection unit according to an embodiment of the present invention, FIG. 3 b is a perspective view of the same when the above is turned over, and FIG. 4a, b, and c are side sectional views showing the same components; FIG. 5a is a plan view of a zero-phase current transformer storage case used in the above; FIG. Figure c is a front view of the same. 1 is a zero-phase current transformer, 4 is a storage case, 5 is a connection pin, 11 is a sensor case, and 15 is a sensor circuit board.

Claims (1)

[Scope of utility model registration request] This end is passed through the end of the current transformer storage case, which has an annular recess on one side into which a toroidal coil-shaped zero-phase current transformer is inserted and has a through hole in the center of the annular recess. One end of the connection pin is connected to the winding end of the current transformer, and the other end of the connection pin is inserted through the bottom plate of the sensor case containing the sensor circuit board at the bottom and the sensor circuit board. and an earth leakage detection unit of an earth leakage breaker that electrically connects and mechanically connects the connection pin and the sensor circuit board.