JPH0123930B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rotary transformer formed by adhesively fixing a ferrite core equipped with a coil on its inner peripheral surface and a terminal having a terminal pin.

Structure of conventional example and its problems A conventional rotary transformer is shown in FIG. 1 as a partially sectional perspective view and FIG. 2 as a cross-sectional view, and as shown in FIG. The side ferrite core 1 is fitted into a cylindrical recess 2a provided in an insulating rotating side terminal 2 and fixed with an adhesive.
is fixed. On the other hand, the fixed-side ferrite core 5 is fixed to the fixed-side terminal 6 and installed on a fixed base 7. Further, the rotating shaft 3 is supported by a bearing 12 provided on the inner periphery of the stationary ferrite core 5.

Winding grooves are provided on the inside of the rotating side ferrite core 1 and on the outside of the stationary side ferrite core 5, and a ring-shaped coil 8 is provided in the winding groove.
a, 8b, 9a, 9b, 10a, 10b, 11
a and 11b are arranged to face each other, and the rotating side ferrite core 1 and the fixed side ferrite core 5
are arranged with gaps of several tens of microns in between.
The lead wires 13 of the coils 8a, 9a, 10a, 11a installed in the rotating ferrite core 1 are connected to the lead wire guide groove 14 formed in the axial direction on the inner diameter surface of the rotating ferrite core 1 and the rotating terminal 2.
The lead wire is led out along a lead wire guide groove 15 formed in the lead wire, and is wound around a conductive terminal pin 16 and soldered.

Further, the lead wires 17 of the coils 8b, 9b, 10b, and 11b equipped on the fixed side ferrite core 5 are led out along the lead wire guide groove 18 formed in the axial direction on the outer diameter surface of the fixed side ferrite core 5, and are fixed. It is connected to a conductive terminal pin 19 provided on the side terminal 6.

With the above configuration, the rotation of the rotating shaft 3 is directly transmitted to the rotating ferrite core 1.

However, in the above configuration, adhesive is applied to a part of the outer peripheral surface and end face of the rotating side ferrite core, and when the rotating side ferrite core is fixed to the rotating side terminal 2, the excess adhesive swells up on the rotating side terminal end face.
Alternatively, it may flow out, chuck the outer diameter surface of the rotating side ferrite core 1, and form the coils 8a, 9a, 10.
When winding wires a and 11a, there is a risk of curling at the chucking position, so the amount of adhesive applied must be reduced to prevent the adhesive from flowing out, which has the disadvantage of making it difficult to securely bond. Was.

OBJECTS OF THE INVENTION The present invention was made in view of the above-mentioned drawbacks, and an object of the present invention is to prevent the adhesive from flowing out or swelling, and to perform reliable adhesion.

Structure of the Invention According to the present invention, a chamfered portion is provided at the end of the cylindrical recess of the terminal into which the core is fitted, which forms an adhesive reservoir between the core and the outer diameter surface of the core. It is possible to prevent the liquid from accumulating in the chamfer, flowing out, or forming a bulge.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 is a perspective view of a terminal of a rotary transformer according to an embodiment of the present invention, and FIG. 5 is a sectional view of an assembled state of a terminal and a ferrite core according to an embodiment of the present invention. In the figure, 20 is a ring-shaped terminal made of an insulator, and conductive terminal pins 21a, 21b, 22a, 22b, 23a,
Projection part 26 to which 23b, 24a, 24b are fixed
a, 26b, 26c, and 26d are formed on the outer peripheral surface 25, and the end surface 27 has lead wire guide grooves 28a,
28b, 28c, 28d, while the inner peripheral surface 2
9 has the lead wire guide grooves 28a, 28b, 28
Lead wire guide grooves 30a, 3 connected to c, 28d
0b, 30c, and 30d are provided. Further, the other end surface 31 is formed with a cylindrical recess 34 in which a cylindrical rotation-side ferrite core 32 is fitted and a chamfered portion 33 is provided on the end surface 31 .

Therefore, excess adhesive coming out of the cylindrical recess 34 where the terminal 20 and the ferrite core 32 fit together accumulates in the chamfered part 33 that forms an adhesive reservoir between the outer diameter surface of the ferrite core 32 and the outer diameter surface of the ferrite core 32.

In addition, in this example, there are four protrusions, eight terminal pins, and four lead wire guide grooves, and the lead wire guide grooves are provided at the positions of the protrusions, but the positional relationship between the protrusions and the lead wire guide grooves and the terminal The number of pins and lead wire guide grooves may be arbitrary. Furthermore, the terminal pin may protrude in any direction as long as the lead wire can be wound around it.

Effects of the Invention As described above, the present invention has a configuration in which the outer diameter surface of a cylindrical core is fitted into a cylindrical recess formed in the inner circumferential portion of a terminal and fixed with an adhesive. A chamfered part that forms an adhesive reservoir between the cylindrical recess and the outer diameter surface of the core is provided, which prevents excess adhesive from dripping or swelling, stabilizing product quality, and improving adhesive properties. It has great practical effects, such as being able to sufficiently apply the agent and achieve reliable adhesive fixation.

[Brief explanation of drawings]

FIG. 1 is a partially sectional perspective view of a conventional rotary transformer, FIG. 2 is a sectional view of FIG. 1, FIG. 3 is a perspective view of a conventional terminal, and FIG. 4 is a rotary transformer according to an embodiment of the present invention. FIG. 5 is a perspective view of the terminal and a sectional view of the assembled state of the terminal and ferrite core of the rotary transformer in the embodiment of the present invention. 20...Terminal, 21a, 21b, 22a,
22b, 23a, 23b, 24a, 24b...terminal pin, 29...inner peripheral surface, 32...ferrite core, 33...chamfered portion, 34...cylindrical recessed portion.

Claims (1)

[Claims] 1 A ring-shaped terminal made of an insulator having a plurality of terminal pins parallel to the central axis, the outer diameter surface of which fits into a cylindrical recess formed on the inner circumference of the terminal, and is fixed by adhesive using an adhesive. a cylindrical recess into which the core is fitted, the coil being installed in a winding groove formed on the inner circumferential surface of the core and electrically connected to the terminal pin; A rotary transformer including a chamfered portion forming an adhesive reservoir portion between the end portion and the outer diameter surface of the core.