JPH03231411A - Resin case storage type current transformer - Google Patents

Abstract

PURPOSE:To enable assembly property to be improved by holding a current transformer which is stored into a case using opposing resin case surfaces and a terminal plate by mounting the terminal plate to an opening surface of the resin case. CONSTITUTION:A terminal plate 15 with a recessed part 17 is mounted to an opening surface of a resin case 11 through a protruding stripe part 14 and a current transformer main body 18 to be stored within the case 11 is sandwiched between a terminal plate 15 and a surface 11d of the opposing case 11. Then, a resin 24 is filled into a space of the case 11, thus forming a resin case storage type current transformer and thus enhancing assembly property with this configuration.

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention (Industrial Field of Application) The present invention relates to a resin case housing type flow meter in which a current transformer main body is housed in a resin case and filled with resin.

(Prior art) A method for manufacturing a current transformer in which the current transformer body is covered with resin is to place the current transformer body in a mold and inject resin so as to cover the outer periphery of the current transformer body. After solidifying, the current transformer body is taken out from the mold, and the current transformer body is housed in a synthetic resin case, and resin is injected into the resin case so as to cover the outer periphery of the current transformer body and then solidified. There is. In the former method, the use of the mold is restricted until the resin hardens, so the latter method of using a resin case is advantageous for mass-produced products.

The latter conventional example is shown in FIGS. 5 and 6. That is, the case 1 made of synthetic resin is shaped like a container with one side open (the left side as shown in FIG. 7), and a cylindrical part 3 through which the primary conductor passes is formed on the side 1c opposite to the open side 1a. It protrudes inward.

Further, a mounting opening 2 is formed on the side surface 1b adjacent to the open surface 1a of the case 1, and a terminal plate 4 having a plurality of terminals 5, for example, six terminals 5, is provided in the mounting opening 2 so as to close the mounting opening 2. are attached and sealed by adhesive. The current transformer main body 6 housed in this case 1 has an annular iron core 7
The secondary coil 8 is wound around the secondary coil 8, and is fitted into the cylindrical part 3 via a fixing spacer 9, and each solar wire 8a of the secondary coil 8 is connected to the terminal 5 of the terminal board 4. There is. Then, a resin 1 is placed inside the case 1 so as to cover the outer periphery of the current transformer main body 6.
0 is injected and solidified.

(Problems to be Solved by the Invention) According to the above configuration, when the current transformer main body 6 moves due to the injected resin 10, the lead wire 8a of the secondary coil 8 may be disconnected, or the secondary coil 8 may be connected to the terminal 5. Since there is a problem that contact may cause dielectric breakdown, it is common to fix the current transformer main body 6 to the case 1. For this reason, when fitting the current transformer main body 6 to the cylindrical part 3, a spacer 9 is inserted between the inner peripheral part and the cylindrical part 3, but due to an error in assembling the current transformer main body 60, Since a dimensional error occurs between the spacer 9 and the shaped portion 3, the thickness of the spacer 9 must be changed each time.
There was a problem of poor assembly.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a resin-cased current transformer that can improve ease of assembly.

[Structure of the Invention] (Means for Solving the Problems) The resin-cased current transformer of the present invention has a container shape with one side open, and the other side has a mounting opening connected to the opening. At the same time, a resin case having a cylindrical part through which the primary conductor passes protrudes inward is provided on a surface facing the opening, and is fitted into the resin case on the outer periphery of the cylindrical part. The current transformer main body is housed, a terminal plate is attached to the case so as to close the mounting opening from the inside, and the case is filled with resin, and the terminal plate is attached to the opposite case. The present invention is characterized in that the current transformer main body is sandwiched between the side surfaces.

(Function) According to the resin case storage type current transformer of the present invention, when the current transformer main body is stored in the resin case, the current transformer main body is sandwiched between the terminal board and the side surface of the case that faces the terminal board. Therefore, there is no need to insert a spacer to fix the current transformer body to the case.

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

The resin case 11 is made of thermoplastic resin such as polyethylene terephthalate or thermosetting synthetic resin such as polyester premix, and is formed into a rectangular container shape.
The upper surface shown in Figure 4) is open and the open part is indicated by lla)
A cylindrical portion 12 through which a primary conductor passes upward is provided on the bottom surface 11b, and a rectangular portion 12 is provided on the other surface 11c (the front surface shown in FIG. 4) and is continuous with the open portion 11a and opens upward. A mounting opening 13 is formed. This attachment opening 13 is a portion to which a terminal plate 15, which will be described later, is attached, and protrusions 14, 14 are protruded inward from both edges. The terminal board 15 is molded from a thermoplastic resin such as polyethylene terephthalate or a thermosetting synthetic resin such as a polyester premix, and has a plurality of, for example, six, terminals 16 embedded in a thick terminal mounting portion 15a. A recess 17.17 is formed at the edge, into which the protrusion 14.14 fits. The current transformer main body 18 is formed by winding a secondary coil 20 around an annular iron core 19, and an insulator (not shown) is wound around the outside of the secondary coil 2o. The external dimensions of the current transformer main body 18 can be adjusted by changing the number of turns of the insulator.
The distance between the terminal plate 1d and the terminal plate 15 attached to the case 11 is set to be slightly larger, for example, by about 1 to 3 mm. Therefore, now, with each solar wire 21 of the secondary coil 20 of the current transformer body 18 connected to the terminal 16 of the terminal plate 15, the current transformer body 18 is fitted into the cylindrical portion 12 again. By storing the terminal board 15 in the resin case 11 so that the concave part 17 fits into the protrusion part 14, the terminal board 15 is arranged so that the terminal mounting part 15a faces the mounting opening part 13, and the lower end part 15b is attached to the resin case 11 so as to be in close contact with the edge of the mounting port 13 and to close the mounting port 13 from the inside, and the current transformer main body 1'8 is connected to the terminal plate 15 and the surface 11d of the resin case 11. It is held between Note that the current transformer main body 18 is restricted from moving from side to side in FIG. 1 by protrusions 22.degree. In this way, the current transformer main body 18
A resin 24 such as an epoxy resin is injected and solidified into the resin case 11 containing the terminal board 15 through the opening 11a.

According to the above embodiment, the following effects are achieved. That is, when the current transformer main body 18 is housed in the resin case 11, the current transformer main body]8 is sandwiched between the surface 1.1d of the resin case 11 and the terminal plate 15 and fixed to the resin case 11. There is no problem that the current transformer main body 18 is moved by the injected resin 24 and the lead wire 21 of the secondary coil 20 is disconnected, or that the secondary coil 20 contacts the terminal 16 and causes dielectric breakdown. Since there is no need to insert the spacer 9 between the inner peripheral part of the current transformer main body 6 and the cylindrical part 3 as in the conventional case, the assembly work of storing the current transformer main body 18 in the resin case 11 is easy. become. Further, the terminal plate 15 is pressed by the outer circumferential portion of the current transformer main body 18 and is elastically pressed against the circumferential edge of the mounting opening portion 13, and as in the above embodiment, the concave portion 17
By fitting the protruding portion 14 with the protruding portion 14, the injected resin 24 will not leak from the joint surface. Therefore, there is no need to adhere the terminal board to the mounting opening of the resin case, and there is no need to seal the periphery, as in the conventional case, making the assembly work easier.

In the above embodiment, the concave portion 17 and the protruding portion 14 are provided and fitted together, but they may be formed into a deck shape and pressed into contact with each other. Further, if the current transformer main body 18 is held with sufficient force by the terminal plate 15 and the surface lid of the resin case 11, the protrusion 2223 may be provided as necessary.

[Effects of the Invention] As is clear from the above description, the resin case-housed current transformer of the present invention has a resin case that is open on one side, and has a mounting opening connected to the open area formed on the other side of the resin case, When installing the terminal board so as to close this installation opening from the inside, the current transformer body is sandwiched between the terminal board and the surface of the resin case facing it, so the current transformer body can be stored in the resin case. This has the effect that it can be fixed with just one step, and the ease of assembly can be significantly improved.

[Brief explanation of drawings]

1 to 4 show one embodiment of the present invention, in which FIG. 1 is a cross-sectional view, FIG. 2 is a vertical cross-sectional view, FIG. 3 is a cross-sectional view showing enlarged details, and FIG. Figure 4 is a perspective view of the case and terminal board, and Figures 5 and 6 are the conventional example of Figures 1 and 2.
It is a figure equivalent figure. In the figure, 11 is a resin case, lla is an open part, 11c and lld are surfaces of the resin case, 13 is a mounting opening, 14 is a protrusion, 15 is a terminal plate, 17 is a concave part, and 18 is the current transformer body ,
24 indicates resin.

Claims (1)

[Claims] 1. A resin case that is shaped like a container with one side open, has a mounting opening connected to the opening on the other side, and has a cylindrical part through which the primary conductor penetrates protruding inward on the surface facing the opening. a current transformer main body housed in the resin case so as to fit around the outer periphery of the cylindrical portion; and a side surface of the resin case that is attached to the resin case so as to close the mounting opening from the inside and faces the resin case. A resin case-housed current transformer comprising a terminal plate that sandwiches the current transformer main body therebetween, and a resin filled in the resin case.