JP2816010B2 - Earth leakage breaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention] (Industrial application field) The present invention relates to an earth leakage breaker in which a zero-phase current transformer and an earth leakage detection unit are integrated.

(Prior Art) In recent years, downsizing of an earth leakage breaker has been required. For this reason, conventionally, for example, one disclosed in Japanese Patent Application Laid-Open No. 2-135643 has been considered, which is shown in FIGS. 5 and 6. That is, reference numeral 1 denotes a case made of an insulating material, and a power terminal block 2 and a load terminal block 3 are integrally formed at both ends thereof, and the power terminal block 2 and the load terminal block 3 are connected to the power terminal block. 4 and a load-side terminal 5 are provided. A main circuit conductor 9 composed of a fixed contact 6a, a movable contact 6b, a movable contact 7 and a flexible conductor 8, which are main circuit contacts, is formed between the power supply terminal 4 and the load terminal 5. 10 is an overcurrent detection device interposed in the main circuit conductor 9, 11
Is a zero-phase current transformer having the main circuit conductor 9 as a primary conductor, and 12 is a leakage detecting unit for detecting a leakage based on the output of the zero-phase current transformer 11. 13 is an opening formed in the bottom of the case 1, 14 is a storage recess formed below the load-side terminal block 3,
Reference numeral 15 denotes a back cover attached to the bottom of the case 1. This conventional example includes an overcurrent detection device 10, a main circuit conductor 9, a zero-phase current transformer 11
Then, the electric leakage detector 12 is assembled, inserted into the case 1 from above, and the electric leakage detector 12 is pulled out of the case 1 through the opening 13 (at this time, the back cover 15 is not attached). Then, the leakage detecting unit 12 is housed in the housing recess 14 below the load-side terminal block 3.

(Problems to be Solved by the Invention) In the above-described configuration, the leakage detection unit is provided in a narrow work space.
Since the storage 12 must be stored in the storage recess 14, there is a problem that workability is extremely poor.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an earth leakage breaker with improved workability in assembly.

[Effects of the Invention] (Means for Solving the Problems) The earth leakage breaker of the present invention includes a case made of an insulating material,
A main circuit conductor disposed in the case, having a main circuit contact, one end of which is connected to a power supply terminal and the other end of which is connected to a load terminal; and a zero-phase transformer having this main circuit conductor as a primary conductor. Current source, a leakage detection unit that opens the main circuit contact according to the secondary side current of the zero-phase current transformer, and an overcurrent that detects the overcurrent of the main circuit conductor and opens the main circuit contact An opening is formed in the case where the zero-phase current transformer, the leakage detector, the overcurrent detector, and the load terminal are mounted in the case, and the zero-phase current After the detector, the leakage detector, the overcurrent detector and the load terminal are mounted on the case, the load side terminal block having the inter-electrode insulating wall separating the overcurrent detector and the load terminal is attached to the opening. It is characterized by having such a configuration.

(Operation) According to the earth leakage breaker of the present invention, since the zero-phase current transformer, the earth leakage detection unit, the overcurrent detection device, and the load side terminal are located at the open part of the case, assembly work can be performed in a wide work space. And assemblability is improved. In addition, since the load-side terminal block having the inter-electrode insulating wall portion that partitions between the overcurrent detection devices and the load-side terminals is attached to the opening after the mounting, the insulation performance is improved.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

21 is a case, which is an upper case made of insulating material.
, A lower case 23, and a back cover 24 attached to the bottom surface 23a of the lower case 23.
Side wall portions 23b, 23b are erected from both side surfaces of 23a. Reference numeral 25 denotes three fixed contact blocks mounted on one end (the left side in FIG. 1) of the lower case 23. One end of the fixed contact block is bent in a U-shape and fixed here as a main circuit contact. A contact 26 is attached, and a power supply side terminal 27 is integrally formed at the other end. The lower case 23 has a shield 2 between the fixed contact blocks 25, 25.
An insulating wall portion 28 is provided upright from the bottom portion 23a, and an opening portion on the right side of FIG.
29 are formed. Reference numeral 30 denotes a movable contact base for three phases which is arranged so as to correspond to the fixed contact base 25 for three phases. A movable contact 31 which is a main circuit contact is attached to these ends. Guide grooves 23c, 23c are formed in the side walls 23b, 23b of the lower case 23, and the three-phase movable contact stand 30 is operated integrally with a movable insulating stand 32 guided by the guide grooves 23c, 23c. It is normally urged upward by the separating spring 33. Reference numeral 34 denotes an operating mechanism, which includes a frame 35 attached to the walls 23d, 23d of the lower case 23, a handle 37 supported by the frame 35 via pins 36, and projecting upward through the upper case 22. ,
One end of the first link 39 is connected to the handle 37 via a pin 38, and the intermediate portion is connected to the other end of the first link 39 via a pin 40. And an L-shaped second link 41 to be pressed. Further, a catch 42 is rotatably supported on the frame 35 via a shaft 43 at an intermediate portion. A catch pin 44 is provided at one end of the catch to be engaged with the other end 41b of the second link 41. A trip rod 45 is provided at the other end. 46 is an overcurrent detection device for three phases, which is a core fixed to a frame 47
48, a coil 49 wound around the core 48, and a frame 47
A movable iron piece 50 that is rotatably supported by the coil 49 and is attracted by the core 48 when an overcurrent flows through the coil 49 to drive the trip rod 45 of the catch 42, and a spring that constantly urges the movable iron piece 50 in the opening direction. It is composed of 51. 52 is a three-phase load-side terminal attached to one end of the coil 49 of the overcurrent detection device 46. Reference numeral 53 denotes flexible conductors for three phases, each of which has an insulating tube on the outer periphery and penetrates through the zero-phase current transformer 54 to serve as a primary conductor thereof.
, And the other end is connected to the other end of the coil 49 of the overcurrent detection device 46. The main circuit conductor 55 is constituted by the fixed contact stand 25, the movable contact stand 30, and the flexible conductor 53. Reference numeral 56 denotes a leakage detection unit, which is connected to the zero-phase current transformer 54 through a lead wire (not shown).
Detects a leakage current, operates a leakage extraction relay (not shown) according to the secondary current to drive the catch 42.

Reference numeral 57 denotes a load-side terminal block made of an insulating material, on which two inter-electrode insulating walls 58 are formed to partition between the overcurrent detection device 46 and the load-side terminals 52. The load-side terminal block 57 has a tip protruding ridge 58a of the inter-electrode insulating wall 58 and a wall 23d.
Is arranged in the open portion 29 so as to fit into the concave ridge portion 23e, and is fixed to the bottom surface portion 23a by a screw 59 inserted from below.

 Incidentally, reference numeral 60 denotes an arc extinguishing device of the Darion grid type.

 Next, an assembling procedure will be described.

(1) Perform the following temporary assembly. That is, the load side terminal 52 is attached to the coil 49 of the overcurrent detection device 46 for three phases, and the flexible conductor 53 for three phases passes through the zero-phase current transformer 54 and one end is connected to the movable contact stand 30. And the other end of the coil 49 of the overcurrent detection device 46.
Connect to In addition, a leakage detector is installed on the secondary side of the zero-phase current transformer 54.
56 is connected via a lead wire, and the movable contact stand 30 for three phases is assembled to the movable insulating stand 32.

(2) The fixed contact blocks 25 for the three phases are placed in the lower case 23 with insulating walls 28.
Is fixed with screws 61 so that the back cover 24 is attached to the bottom surface 23a of the lower case 23.

(3) Insert the separation spring 33 into the lower case 23.

(4) Connect both ends of the movable insulating table 32 to the guide grooves 23 of the lower case 23.
c, 23c from above, and insert both ends of the frame 47 of the overcurrent detection device 46 of each phase into the grooves 23f, 23f formed in the wall 23b or 23d of the lower case 23 from above, and Overcurrent detector 46, zero-phase current transformer 54, and leakage detector 56
To the opening 29, and assemble.

(5) Advance the load-side terminal block 57 from the side of the lower case 23 to the left as shown in FIG. 1, and insert the two inter-electrode insulating walls 58 between the overcurrent detector 46 and the load-side terminals 52. And the tip ridge 58a
Is fitted into the concave strip 23e. And this load side terminal block 57
Is fixed to the bottom surface 23a by inserting the screw 59 from below. In this case, the leakage detecting section 56 is housed in a housing recess 62 formed in the load-side terminal block 57.

(6) The arc extinguishing device 60 is disposed in the lower case 23 so as to cover the fixed contacts 26 and 31 serving as the main circuit contacts, and the operating mechanism 34 is attached to the walls 23d and 23d of the lower case 23 by screwing.

(7) Finally, the upper case 22 is attached to the lower case 23 from the side.

Reference numeral 63 denotes a power supply terminal screw screwed into the power supply terminal 27, and reference numeral 64 denotes a load terminal screw screwed to the load terminal block 57 via the load terminal 52.

According to the above embodiment, the following effects can be obtained. That is, an open portion 29 is formed in the lower case 23, and in this open portion 29, an overcurrent detection device 46 for three phases, a load-side terminal 52, a flexible conductor 53, a zero-phase current transformer 54, and a leakage detection portion Because I tried to assemble 56,
It is easy to assemble, and the workability of assembling is improved.
The insulation tube is not damaged. Thus, since the two inter-electrode insulating walls 58 are interposed between the overcurrent detection devices 46 and between the load-side terminals 52, the insulation performance is improved.

[Effect of the Invention] The earth leakage breaker of the present invention is a zero-phase current transformer in a case,
An open part is formed in the area where the leakage detector, overcurrent detector and load terminal are mounted, and after these zero-phase current transformer, leakage detector, overcurrent detector and load terminal are mounted on the case, Since the load-side terminal block having the inter-electrode insulating wall portion that partitions between the overcurrent detection devices and the load-side terminals is attached to the open portion, an effect of improving the workability of assembly can be obtained.

[Brief description of the drawings]

1 to 4 show an embodiment of the present invention. FIG. 1 is an exploded perspective view, FIG. 2 is a vertical sectional front view, FIG. 3 is a plan view of a lower case, and FIG. FIG. 5 is a longitudinal sectional front view in the middle, and FIG. 5 is a diagram corresponding to FIG. 2 and FIG. 6 is a diagram corresponding to FIG. In the figure, 21 is a case, 26 is a fixed contact (main circuit contact), 27 is a power supply side terminal, 29 is an open portion, 31 is a movable contact (main circuit contact), 46 is an overcurrent detection device, and 52 is a load side terminal Reference numeral 54 denotes a zero-phase current transformer, reference numeral 55 denotes a main circuit conductor, reference numeral 56 denotes a leakage detection unit, reference numeral 57 denotes a load-side terminal block, and reference numeral 58 denotes an inter-electrode insulating wall.

Claims (1)

(57) [Claims] 1. A case made of an insulating material, a main circuit conductor having a main circuit contact disposed in the case, one end connected to a power supply terminal and the other end connected to a load terminal, A zero-phase current transformer having the main circuit conductor as a primary side conductor, a leakage detecting unit for opening the main circuit contact according to a secondary side current of the zero-phase current transformer, and an overcurrent of the main circuit conductor And an overcurrent detection device that detects the current and opens the main circuit contact, wherein the zero-phase current transformer, the leakage detection unit, the overcurrent detection device, and the load-side terminal in the case are mounted. Forming an open part, these zero-phase current transformer,
After the overcurrent detection device and the load-side terminal are attached to the case, a load-side terminal block having a pole insulating wall portion that partitions between the overcurrent detection device and the load-side terminal is attached to the opening. Characteristic earth leakage breaker.