JP3404698B2 - Iron core for clamp type transformer - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an iron core for a clamp-type transformer for obtaining a signal output and a power supply by penetrating an existing electric wire without cutting it. 2. Description of the Related Art Conventionally, a clamp type current transformer composed of two split iron cores has been engaged with an existing power line for current measurement and power measurement. The technique for making the joining surfaces of the two split cores in close contact is difficult, and the means for tightening the two split cores is complicated and large, and there is a drawback that the labor for construction is troublesome. SUMMARY OF THE INVENTION An object of the present invention is to improve the above-mentioned drawbacks of the conventional device, and to provide a very good adhesion between the two divided cores and a simple structure. An object of the present invention is to provide a clamp-type transformer core that is small, lightweight, easy to handle, and does not require installation work. [0004] In order to solve the above-mentioned object, a clamp-type transformer core according to the present invention is provided outside of one of two divided cores obtained by dividing an annular core into two parts. At the position, two elastic metal plates sandwiching the two divided cores in the thickness direction are provided to form a hinge portion for rotatably connecting the two divided cores to each other, and the two divided cores are disposed outside the other divided portion. The two elastic metal plates constituting the hinge portion each have a bent portion orthogonal to the longitudinal direction at an intermediate portion in the longitudinal direction, and each of the two elastic metal plates constituting the hinge portion has one end portion in the longitudinal direction. And the other end is axially attached to the end of the other split core. When the fixing portion of the clamp-type transformer core is removed, the existing electric wire is passed through the divided portion, and the fixing portion is tightened, the bent portions of the two elastic metal plates of the hinge portion are extended. The joint surface is brought into close contact by applying a pressing force to the joint surface on the hinge portion side of the split core. At this time, the bent portions of the two elastic metal plates are extended by different lengths so as to correct mounting and other slight dimensional errors, so that a uniform pressing force can be applied to the entire joint surface, thereby joining. Make sure the surfaces are in close contact. In addition, the bonding surface on the fixing portion side is also brought into close contact by tightening the fixing portion. An embodiment of a clamp type transformer core according to the present invention will be described with reference to the drawings. FIG. 1 is a front view, and FIG. 2 is a bottom view showing a hinge portion side. Two divided cores 1 and 2 obtained by dividing an annular core made of a well-known core material such as ferrite by two divided portions A and B are respectively housed in a metal case and connected to a secondary winding (not shown). The lead 3 thus obtained is derived. Two elongated elastic metal plates 4 and 5 are provided on both side surfaces of the metal case at positions outside the division portion B so as to straddle the division iron cores 1 and 2, respectively, and these rotatably couple the division iron cores 1 and 2 to each other. It constitutes a hinge part. [0007] The two elastic metal plates 4 and 5 have the same shape and are provided with bent portions 4a and 5a perpendicular to the longitudinal direction at the intermediate portions in the longitudinal direction, respectively. It can be expanded and contracted. The two elastic metal plates 4 and 5 are arranged to face each other so as to sandwich the metal case of the split cores 1 and 2, and one ends 4 b and 5 b are fixed to the split core 1 side, and the other ends 4 c and 5 c are fixed. 5c
Are axially mounted on the divided core 2 side, whereby the two divided cores 1 and 2 are rotatably coupled in the direction indicated by the arrow C in FIG. A well-known spring-type buckle 6 is provided on the metal case of the split cores 1 and 2 located outside the split portion A, and by engaging this, the joining surface of the split portion A can be strongly pressed and fixed. I can do it. In addition,
This fixing portion is not limited to the spring type buckle, but may be replaced with other known fixing means such as a bolt and a nut. Next, the operation will be described. When the buckle 6 of the clamp-type transformer core is removed, an existing electric wire is passed through the annular core from the divided portion A, and then the buckle 6 is tightened, the two elastic metal plates 4 and 5 of the hinge portion are formed.
Of the split cores 1 and 2
Is applied to press the joint surface of the divided portion B to bring the joint surface into close contact. At this time, since the bent portions 4a and 5a can extend by different lengths, a slight dimensional error such as a mounting error between the two elastic metal plates 4 and 5 can be corrected, and the joining surface of the divided portion B can be corrected. A uniform pressing force can be applied throughout. In addition, the joint surface on the side of the divided portion A is accurately pressed and adhered by the tightening of the buckle 6. As described above, the clamp-type transformer core of the present invention has a simple structure and does not break down, and the adhesion between the two sets of joining surfaces of the two split cores is extremely good. It has a remarkable effect that it is small, lightweight, easy to handle and does not require labor for construction. You can do it.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of a clamp-type transformer core of the present invention. FIG. 2 is a bottom view showing a hinge side thereof. Lead
4, 5 Elastic metal plate 4a, 5a bent portion 6 Spring type buckle A, B Split portion of split core

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01F 27/26 H01F 38/28

Claims (1)

(57) [Claims 1] Two elastic cores for holding both split cores in the thickness direction at positions outside one of the two split cores obtained by dividing the annular core into two. A metal plate is provided to form a hinge portion for rotatably connecting the two split cores to each other, and a fixing portion for detachably connecting the two split cores to each other is provided at a position outside the other split portion to form the hinge portion. Each of the two elastic metal plates has a bent portion at a middle portion in the longitudinal direction and a bent portion orthogonal to the longitudinal direction, and is fixed to one end of the longitudinal direction to the end of one of the divided cores in the thickness direction. A clamp-type transformer core, wherein the other ends are axially attached to the ends of the other split core.