JPH04324607A - Method for protecting annular core - Google Patents

Abstract

PURPOSE:To protect an annular core even when the core is not housed in a case and, at the same time, to use a hard epoxy resin. CONSTITUTION:A protective layer 4 is formed on the outer periphery of an annular core 1 by winding a tape of insulating cloth 2 around the annular core 1 and hardening a soft resin 3 after dipping the core in the a soft resin 3.

Description

[Detailed description of the invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for protecting an annular core that is a component of a toroidal transformer for consumer use.

0002

2. Description of the Related Art Conventionally, to protect this type of annular core, the annular core is protected by: (1) housing the annular core in a case; Alternatively, (1) a coil was wound around the outer circumference of the annular core using a winding machine, and then the coil was impregnated into a soft resin.

0003

[Problem to be solved by the invention] However, the above ■
This structure uses a case in which the annular core is housed, which poses a problem in that the overall size becomes large.

[0004] In the latter structure (2), it is preferable to use an epoxy resin which has excellent insulation and heat resistance as the resin to be impregnated, but since this epoxy resin is hard, it is difficult to impregnate it. As stress due to internal stress is applied to the annular core during contraction during the subsequent hardening process, the properties of the annular core deteriorate, making it undesirable to use it in this respect. The problem was that inferior soft resin had to be used.

[0005]

[Object of the Invention] The present invention has been proposed in view of the above circumstances, and its purpose is to be able to protect the annular core without using a case, and to protect the annular core without using a case. It is an object of the present invention to provide a method for protecting an annular core that does not adversely affect the annular core even when used.

[0006]

[Means for Solving the Problems] The present invention involves taping an insulating cloth 2 around an annular core 1, impregnating the annular core 1 in a soft resin 3, and hardening the resin 3 to form the annular core. The above object is achieved by forming the protective layer 4 on the outer periphery of the protective layer 4 .

[0007]

[Operation] The present invention is constructed as described above, and a protective layer 4 made of an insulating cloth 2 impregnated with a soft resin 3 is provided on the outer periphery of the annular core 1, and the annular core 1 is protected by this protective layer 4. That's what I do.

[0008] Therefore, although this may be housed in a case, it is not necessary to use a case, and in this case, it is possible to prevent the size from increasing.

Furthermore, even when impregnated with a hard epoxy resin, since the protective layer 4 is provided around the outer periphery of the annular core 1, the protective layer 4 absorbs the internal stress caused by shrinkage that occurs when the resin hardens, and the annular core 1 stress can be prevented.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 to 4 show one embodiment of the present invention. Therefore, in the present invention, first, as shown in FIG. 1, at least one layer of tape-shaped insulating cloth 2 is taped around a ring-shaped core 1 made of, for example, a silicon steel plate, which is previously formed in a ring shape. The entire outer periphery of the annular core 1 is covered.

Next, as shown in FIG. 2, the annular core 1 with the insulating cloth 2 wound thereon is wrapped in a soft resin 3 such as silicone rubber.
The resin 3 is soaked into the insulating cloth 2.

After impregnation, it is taken out and the resin 3 is cured to form a protective layer 4, as shown in FIG. In this case, since the resin 3 is soft, it does not adversely affect the annular iron core 1.

[0013] On the outer periphery, as shown in FIG.
By winding the coil 5, a toroidal transformer is completed. This transformer may be impregnated in a hard epoxy resin, or may be coated, molded, etc.

In this case, since there is a protective layer 4 inside, the annular iron core 1 can be protected by this protective layer 4. Note that the protective layer 4 also acts as a cushioning material against external impact, and can protect the annular core 1.

[0015]

As described above, according to the present invention, since the protective layer 4 is provided around the annular core 1, the annular core 1 can be protected by the protective layer 4 without using a case. Note that it is of course possible to put it in a case.

[0016] Furthermore, the annular core 1 can be protected by the protective layer 4 even if it is impregnated with an epoxy-based hard resin 3.
Desired insulation and heat resistance can be obtained without applying stress to the annular core 1.

[0017]

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of taping of an annular core according to the present invention.

FIG. 2 is an explanatory diagram of impregnating a ring-shaped core taped with insulating cloth into a hard resin.

FIG. 3 is an explanatory diagram showing the formation of a protective layer according to the present invention.

FIG. 4 is a perspective view of a transformer completed by winding a coil on a protective layer.

[Explanation of symbols]

1 Annular iron core 2 Insulating cloth 3 Resin 4 Protective layer 5 Coil

Claims (1)

[Claims] 1. An insulating cloth 2 is taped around the annular core 1, the annular core 1 is impregnated in a soft resin 3, and the resin 3 is hardened to form a protective layer 4 on the outer periphery of the annular core 1.
A method for protecting an annular iron core characterized by forming.