JPS5810344A - Shortcircuit sensor coil - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a short-circuit sensor coil for a circuit breaker.

A conventional example is shown in FIGS. 1 and 2. That is,
Consisting of a first coil piece 1 and a second coil piece 2.3, the first coil piece l is a U-shaped plate made of %+1 with a predetermined plate width W and plate thickness T. It is curved, and notches 6 and 7 are formed on opposite sides of both ends 4.5 in the width direction. The widthwise depth D of this notch 6.7 is less than the width W of the board. The second coil piece 2.3 is made of a copper plate having a plate thickness corresponding to the depth D of the notch 6.7, and is formed into a two-figure shape on a plane, with one end 8.9 having a fail ￥u
k has a width W' corresponding to JφT, and the other end has a relief part 1
0.11. This second coil piece 2-3
Fit the one end portions 8 and 9 into the notch portion 6.7, and remove the relief portion 10.
゜11 is the opposing part of the first coil piece 1, that is, the escape part 1
0 to the end 5 and the relief part 11 to the end 6, an insulating gap of P is formed between them, and since -iW>D as described above, the An insulating gap of a distance P2 is also formed between the two coil pieces 2 and 3 facing each other. In this state, if the first coil piece 1 and the second coil piece 2.3 are brazed at the notch 6°7, the result will be as shown in Fig. 1, viewed from the other end 12.13. A closed-loop coil with a perfect circle inside is formed.

However, this short circuit sensor coil is, for example, 225
When applied to a circuit breaker with a large current and large capacity such as an ampere frame, the first coil piece 1 and the second coil piece 1. The third coil piece 2.3 was joined at the punched end face of the thick sheet metal, which had the disadvantage of causing local heat generation during energization due to unstable contact. Another drawback is that the processed products of these members are expensive.

Therefore, an object of the present invention is to provide a short-circuit sensor coil that can be easily and inexpensively processed and can reduce local heat generation.

A 225 ampere frame circuit breaker to which a first embodiment of the present invention is applied is shown in FIGS. 3 to 5. That is, in the figure, 14 is a device stand, 15 is a cover, 16 is a power supply side terminal device, 17 is a load side terminal device, 18... fixed contacts, 19 is a movable contact, 20 is a movable contact, and 21 is a tri-tube. 22 is a handle, 23 is a tripping lever, 24 is a copper stranded wire connected to the movable contact 9, 25
26 is the coil of the plunger type short-circuit sensor A connected to the relay fitting 25; 27 is the second relay fitting connected to the coil 26; 28
is a bimetallic heater connected to the relay fitting 27, 2
9 is a bimetal for overcurrent detection, and 30 is an arc extinguishing amount.

In this configuration, the coil 26 is formed of first to third coil pieces 31 to 33 as shown in FIGS. 4 and 5 in detail. The first coil piece 31 is made by laminating a plurality of copper thin plates 34. Each thin plate 34 has a square outer shape with a leg plate 35 extending from the lower end to the side, and an oval hole in the center by one minute at each corner. 36 is formed by punching, and the corner 36a is located close to the leg plate 35, and a slit 37 is formed which is the opening of the hole 36 extending from the corner 36a to the outer edge of the corner 36a, thereby forming a G-shape in plan. A large number of connecting holes 38 are formed around the periphery of the hole 36 . The second coil piece 32 is a thin copper plate punched into a U-shape in plan, and the inside is formed into an arc with the same radius as the circular arc hole 36, and its vertical dimension H0 is the same as that of the first coil piece 31. The longitudinal dimension H3 from the upper end edge to the slit 37 is the same as the vertical dimension H3, and a connecting hole 38' is formed corresponding to the connecting hole 38. Third coil piece 3
3 is the same as the first coil piece 31.

Therefore, if the center of curvature of the arc of the second coil piece 32 is aligned with the center of the circular arc hole 36 of the first coil piece 31, and the second coil piece 32 is overlapped with the first coil piece 31. ,
The lower end of the second coil piece 32 is the first coil piece 31
The upper edge of the slit 37 coincides with the upper edge of the slit 37, and the third coil element 33 is oriented oppositely to the first coil element 31 as shown in FIG. 4, and the hole center is aligned with the second coil element 32. The rivets 39 are passed through the connecting holes 38 and 38' to be crimped and connected together to form a coil.

When the leg plate 35 is brazed to the leg 40.41i (5) to the relay fitting 25.27, the current flows from the leg 40 of the first coil piece 31 as shown by the arrow P to the second coil piece 31.
The current flows to the coil element 32, and further flows to the third coil element 33.
It flows to its leg 41.

This means that the loop for the first volume will be drawn. Therefore, if a coil cylinder having one plunger is passed through the circular arc hole 36 and supported by the yoke 26', the plunger can be driven by the magnitude of the current.

This circuit breaker connects the terminal device ft16.17 to the wiring path, and when the handle 22 is turned on, the coil 26. Contact points 18.19. The rated current of the wiring path is applied to the internal circuit including the heater 28 . If an accident occurs in the wiring path and overcurrent flows, the heater 28 generates heat and the bimetal 29
, and operate the tripping lever 23. This action releases the latch of the mechanism section 21, the n1 balance is disrupted, and the movable contact 20 is opened.

On the other hand, if a short-circuit accident occurs in the wiring path, the short-circuit current flows through the coil 26, attracts the granger, and directly forcibly opens the movable contact 20, and (6) similarly to the bimetal 29, the tripping lever 23 is activated. This action causes the movable contact 20 to open.

Because of this configuration, this short circuit sensor coil is
The coil can be formed by punching out two types of simple-shaped thin plates and laminating and polymerizing them, and can be manufactured at low cost. Moreover, since they conduct electricity through surface contact with each other, local heat generation can be reduced compared to the conventional method. In addition, fluctuations in coil length and coil cross-sectional area due to variations in thin plates are
By adjusting the plate thickness of the coil piece 32, it is possible to reduce the cost by adjusting the plate thickness of the coil element 32, and to make the length and cross-sectional area of the coil uniform (2) υ,
It is possible to stabilize heat generation.

A second embodiment of the invention is shown in FIGS. 6 and 7.

That is, in this short-circuit sensor coil, half-open uneven portions 42.43 are formed on a thin plate 34' as in the first embodiment by changing the direction of protrusion, and when superimposed, the uneven portions 42.4
3i As shown in FIG. 7, they are press-fitted and stacked, and then the connecting holes 38 and 38' are caulked with caulking studs 39. With this configuration, in addition to the contact on the plate surface of the thin plate 34', press-fit contact between the concavo-convex portions 42 and 43 is ensured, so that a stable reduction in contact resistance can be maintained. The rest is the same as the first embodiment.

Note that the first and third coils of the short-circuit sensor coil of the present invention
The coil element may be punched out of a single plate.

In addition, it can be applied not only to solenoids but also to pot types.

As described above, the short end sensor coil of the present invention has the first
Since the third coil piece is formed into a G-shaped plane and the second coil piece is formed into a U-shaped plane and then overlapped, they can be formed easily and inexpensively (by simple punching and caulking rivets). Moreover, it has the effect of reducing local heat generation.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a conventional example, Fig. 2 is an exploded perspective view thereof, Fig. 3 is a partially cutaway side view of a circuit breaker to which the first embodiment of the present invention is applied, and Fig. 4 is a diagram of a coil. Exploded perspective view, 5th
The figure is a perspective view, FIG. 6 is a perspective view of the thin plate of the second embodiment, and FIG. 7 is a sectional view of the laminated state of the thin plates. 31... First coil piece, 32 Second coil piece, 33... Third coil piece, 34... Thin plate, 35
... leg plate, 36 ... hole, 37 ... slit, 38
, 38'... connecting hole, 39... caulking stud, 40,
4]...Leg, 42°43...Uneven part (9) 19 Bi2 Fig. 1 Fig. 2 Fig. 6 Fig. 7 201-

Claims (3)

[Claims] (1) A first coil piece formed by forming a flat plate into a G-shaped plane;
The flat plate is formed into a U-shape in plan, and when the center of the concave portion of the plate is aligned with the center of the hole of the first coil piece, and the both ends of the plate are overlapped with the center of the hole of the first coil piece. a second coil piece that does not reach the opening; and a second coil piece that has the same shape as the first coil piece and is inverted with respect to the first coil piece. A coil for a short circuit sensor, comprising a third coil piece that is superposed in the same manner as the first coil piece. (2) The short-circuit sensor coil according to claim 1, wherein the first and third coil pieces are laminated. (3) The first and third coil pieces are formed with uneven portions in the thickness direction by half punching, and the uneven portions of each plate are fitted together. Coil for short circuit sensor.