JPS6336654Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a core for a rotary transformer used in a rotary transformer that transmits and receives electrical signals in a non-contact manner while making relative rotational motion.

Conventionally, this type of rotary transformer has been used in V/T/R equipment that records and plays back images of home television equipment, for example, a rotary transformer made of a high magnetic permeability material such as ferrite molded into a flat cylindrical shape. cores are known.

These rotary transformers usually consist of a pair of transformer cores with substantially the same shape on the fixed side and the rotating side, and concentric grooves are formed on the opposing surfaces of the transformer core, and a coil for transmitting and receiving electrical signals is installed. The transformer core was attached to the cylinder member, etc., and each transformer core was fixed to the cylinder member or the like. As a fixing means, the back side of the transformer core is formed into the same flat surface, and this surface is bonded to the cylinder member or the like using an adhesive.

In this case, the gap between the opposing surfaces of the fixed and rotating transformer cores is usually 50 to 100 microns, and the fixed and rotating transformer cores are required to have precise parallelism.

However, with the conventional fixing means described above, differences in adhesive application conditions can cause variations in the gap between the fixed and rotating transformer cores, and careful work is required to maintain uniform parallelism. It was necessary to perform quantitative and qualitative control of the adhesive.

This idea was devised in view of these problems, and its purpose is to provide a core for a rotating transformer that maintains stable adhesion even under temperature changes and can be bonded in a highly accurate position. There is a particular thing.

Preferred embodiments of this invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of the rotary transformer core according to this invention.

In this embodiment, the transformer core 1 is formed into a flat cylindrical shape using a high magnetic permeability material such as ferrite, and a drive shaft for rotationally driving the transformer core 1 is inserted into the center of the transformer core 1. A shaft hole 2 is bored with a predetermined diameter. A concentric groove is formed on the upper surface of the transformer core 1, and a coil 3 having a predetermined shape is fixed in the groove with an adhesive or the like.

On the back side of the transformer core 1, there is a step part 4 cut out in a ring shape with a predetermined depth and width along the outer periphery of the transformer core 1, and the remaining part forms a ring-shaped step part 4 concentric with the shaft hole 2. A convex portion 5 is formed.

In order to fix the transformer core 1 formed in this way to the cylinder 6 etc., when the transformer core 1 is brought into contact with a predetermined position on the cylinder 6, the stepped portion 4
This is done by pouring the adhesive into the stepped portion 4 from this opened portion.
In this case, if the installation surface of the transformer core 1 of the cylinder 6 and the convex part 5 on the back side of the transformer core 1 are processed into a good flat state by polishing or the like, then when pouring the adhesive into the step part 4, By pressing the transformer core 1 lightly from above, the adhesive is prevented from flowing into the convex portion 5, and the transformer core 1 is fixed onto the cylinder 6 while maintaining its parallelism accurately. It is.

In addition, normally the work of fixing the transformer core 1 is done while controlling the quantity of adhesive, but in the case of the transformer core according to this invention, since the stepped portion 4 is opened outward, the adhesive Even if an excessive amount of adhesive is poured, the excess adhesive flows outward and does not affect the parallelism of the transformer core 1.

FIG. 2 shows a second embodiment of this invention.
Stepped portions 4 are formed at two locations on the outer peripheral edge of the transformer core 1 and the inner peripheral edge of the transformer core 1 along the inner shaft 2.
The transformer core 1 is fixed to the cylinder 6 by pouring adhesive into the cylinder 6.

FIG. 3 shows a third embodiment of this invention, in which a plurality of concave grooves having a predetermined width and depth are formed radially from the center on the back side of the transformer core 1,
By pouring adhesive into the stepped portion 4, the transformer core 1 is fixed as in the previous embodiment.

FIG. 4 shows a fourth embodiment of this invention, in which a concave groove having a predetermined width and depth is formed on the back side of the transformer core 1 so as to surround the shaft hole 2 from all sides. Then, the transformer core 1 is fixed by pouring adhesive.

FIG. 5 shows a fifth embodiment, in which a spiral groove is formed on the back side of the transformer core 1 from the shaft hole 2 to the peripheral end to form a stepped portion 4. . Note that this invention can also be implemented by, for example, combining the first embodiment and the third embodiment.

As described above, the rotary transformer core according to the present invention has a stepped portion or a groove portion formed on the back surface of the transformer core on the fixed side of the rotary transformer, which is opened to the outside while in contact with the cylinder, for filling with adhesive. Therefore, the adhesive area between the transformer core and the cylinder is limited to the step or groove, which reduces the area, which prevents peeling due to differences in the coefficient of thermal expansion of these parts, and allows for highly accurate positioning of the transformer core. can.

[Brief explanation of drawings]

FIG. 1 shows a first embodiment of the rotary transformer core according to this invention, in which a is a sectional view and b is a sectional view.
is a back view. 2 to 5 are back views showing other embodiments of this invention. 1...Transformer core, 2...Shaft hole, 3...Coil, 4...Step portion.

Claims (1)

[Scope of utility model registration request] It is equipped with a pair of transformer cores made of a high magnetic permeability material such as ferrite formed into a flat cylindrical shape and consisting of a stationary side and a rotating side that are arranged opposite each other, and a coil installed in the transformer core to allow relative rotational movement. In a rotary transformer that transmits and receives electrical signals in a non-contact manner, a step or groove for filling adhesive is formed on the back surface of the transformer core on the fixed side, which opens outward while in contact with the cylinder. A core for rotating transformers featuring: