JPS631404Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an earth leakage detection unit for an earth leakage breaker.

Conventionally, there was a device of this kind as seen in Japanese Patent Application Laid-Open No. 51-4813. Generally, since a drop impedance is installed at one end of the earth leakage detection circuit, heat generation may adversely affect other electronic components.
Also, there was a mixture of high pressure and low pressure.

Therefore, a step-down impedance has to be provided externally, but it is often attached to the sensor case, which is still not sufficient to prevent heat generation, and the assembly is troublesome. Also, the sensor assembly process includes steps such as installing a test switch, fixing a resistor, and connecting. Furthermore, zero-phase current transformer (hereinafter referred to as ZCT)
) are connected by lead wires, so
There was a problem that the work involved fixing the ZCT.

The present invention was developed in view of these problems, and its purpose is to prevent the heat generation of the impedance element from affecting the sensor unit through the intervention of a current transformer storage case (hereinafter referred to as the ZCT storage case). In addition, it prevents high current parts and low current parts from
To provide an earth leakage detection unit for an earth leakage breaker which is separated by a ZCT storage case to prevent cross-contact, and which is easy to assemble by being made into blocks and whose parts can be easily managed.

The configuration of the present invention will be explained below with reference to the illustrated embodiments.As shown in FIGS. 1 to 6, one end 1, two
The upper ends 8 of the connecting fittings 7 are caulked and connected to the other ends 5 and 6 of the step-down capacitor 3 and the surge absorbing resistor 4, respectively, which are connected to an AC power supply.
Bend both edges 9 below the center into a U-shape,
The elastic clamping piece 13 is formed by leaving the upper end 11 of the U-shaped bent part 10 and providing a cut 12 along the folding line from the lower end, and bending the central part 14 of both elastic clamping pieces 13 inward. A cut-and-raised part 17 with the tip 16 facing upward is formed on the back of the U-shaped bent part 10 of the connection fitting 7, and a raised part 17 is formed on the end of the ZCT storage case 18. At least four connecting pins 19, 20 are planted, and the upper and lower ends 21, 22 of each connecting pin 19, 20 are ZCT
Protruding from both upper and lower surfaces 23 and 24 of the storage case 18,
The upper end portions 21 of two specific connecting pins 19 and 20 of the storage case 18 are fitted into the upper end surface of the flat external component fixing base 25 attached to the upper surface 23 side of the ZCT storage case 18. A cylindrical socket portion 26 is formed to protrude, and the cylindrical socket portion 26
Insert the connecting fitting 7 into the connecting fitting 7 , engage the tip 16 of the cut-and-raised portion 17 of the connecting fitting 7 with the lower surface 27 of the external component fixing base 25 , and attach the two specific connecting pins 19 to the connecting pin holding portion 15 . The upper end 21 is inserted, the winding end 29 of the ZCT 28 is connected to the upper end 21 of the remaining connecting pin 20, and the lower end 22 of each connecting pin 19, 20 is connected to the sensor case 31 in which the earth leakage detection circuit 30 is built. Insert into terminal holes 32 and 33 and connect ZCT2
8 and the earth leakage detection circuit 30, and also supplies power to the earth leakage detection circuit 30. In FIG. 1, 35 is a test winding for passing an unbalanced current, and 36 is a test switch. FIG. 2 shows a side cross-sectional view of the earth leakage detection unit shown in FIG. After being locked to the lower surface 27 of the accessory fixing base 25, it is fitted to the connecting pin 19 of the ZCT storage case 18. Figure 3 shows the ZCT storage case 18 with the external component fixing base 25 attached in the same process as above, and the earth leakage detection circuit 30.
FIG. 3 is a side cross-sectional view showing how the sensor case 31 is connected to the sensor case 31 containing the sensor. Furthermore, Figures 4 and 6a
are top views of the external component fixing base 25 and the ZCT storage case 18, respectively. As shown in the figure, the connection between the ZCT 28 and the earth leakage detection circuit 30 is made by the connection pin 19 on one side, and the connection on the other side is made using the connection pin 19. Power is supplied to the earth leakage detection circuit 30 through the connection pin 20 of.

Since the present invention is constructed as described above, the ZCT storage case prevents the heat generated by the impedance element from affecting the sensor unit, and the strong current part consisting of the external component fixing base and the weak current part consisting of the sensor case Since the parts are separated by the ZCT storage case, it is possible to prevent cross-contact, resulting in high safety.Furthermore, since the parts are made into blocks, assembly is easy, and parts management is also easy.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of an earth leakage detection unit according to an embodiment of the present invention, Fig. 2 is an exploded side sectional view of the same essential parts, Fig. 3 is a side sectional view showing the connection state of the above, and Fig. 4 is A plan view of the external component fixing base used in the above, FIG. 5a is a perspective view of the connection fitting used in the above,
Figure b is a front view of the same as above, and Figure 6 a is used for the same as above.
A plan view of the ZCT storage case, Figure b is a side view of the same, and Figure c is a front view of the same. 3 is a capacitor, 4 is a resistor, 7 is a connection fitting,
13 is an elastic clamping piece, 17 is a cut-and-raised part, and 18 is a
ZCT storage case, 19 and 20 are connection pins, 25
26 is the external parts fixing base, 26 is the cylindrical socket part,
31 is a sensor case, and 32 and 33 are terminal holes.

Claims (1)

[Scope of utility model registration request] a current transformer storage case that houses a zero-phase current transformer that detects leakage current and has two connection pins that connect the winding ends of the zero-phase current transformer and two other connection pins that protrude upward and downward; a sensor case that abuts against the bottom surface of the current transformer storage case and has terminal holes through which at least four connection pins are inserted, and has a leakage current detection circuit connected to the connection pins; and a sensor case that abuts against the top surface of the current transformer storage case and has
A leakage current detection unit for a leakage current breaker, characterized in that it comprises a step-down impedance element having one end connected to a connecting fitting which is inserted into and connected to the other two connecting pins, and an external component fixing base equipped with a current-limiting resistor and a test switch connected to a test winding which passes through a zero-phase current transformer.