JPS58220410A - Rotary transformer - Google Patents

Abstract

PURPOSE:To eliminate cross-talk by making the opposing faces of rotor and stator convex and concave faces to engage each other with a specified distance and dividing those faces and providing non-magnetic bodies between those faces in rotor and stator that rotate relatively to each other and are provided with a plurality of coils on their opposing faces in order to give electromagnetic coupling between them. CONSTITUTION:When a stator 5 and rotor 6 that are opposite to each other form a rotary transformer, a plurality of annular magnetic bodies 81 and 82 are fit on the outer circumferential face of the stator 5 with a distance between them, and coils 111 and 112 are provided on the tip ends of those magnetic bodies. Further, annular magnetic bodies 91 and 92 that enclose the annular magnetic bodies 81 and 82 are provided on the rotor 6 in such a fashion that the magnetic bodies are positioned opposite to the stator 5, and on the inside of the magnetic bodies 91 and 92 coils 121 and 122 are formed that are opposite to the coils 111 and 112 respectively. In the gap between the separated magnetic bodies 91 and 92 a non-magnetic material layer 10 is inserted. With this construction magnetic coupling becomes large and cross-talk is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary transformer, and particularly to a rotary transformer with less crosstalk.

Rotary transformers are widely used to transmit signals between rotating and stationary circuit parts, such as signal reception and reception between the rotating head of a video recorder and a stationary circuit part, and control equipment. It has applications such as connecting rotating sensors and stationary circuit parts. In these applications, if there are a plurality of heads or sensors, the four-tally transformer is also configured into a plurality of channels. Fig. 1 shows a conventional example of a multi-channel disk-shaped rotary transformer, in which a highly permeable disk-shaped rotor 1 supported by a rotating shaft 3 has a number of concentric centers corresponding to the number of channels (two in the figure) on the surface of a highly permeable disk-shaped rotor 1. Cut a groove in it and insert the winding 4 to connect to the heads H* and H2, respectively.
Similarly, a highly permeable disc-shaped stator 2 is provided with concentric grooves and windings corresponding to the four-way grid on the surface of the stator 2 to form a p-tally transformer. Since the rotor and the stator are each manufactured from a single piece of ferrite, permanent iron, etc., it is impossible to avoid interlinkage of magnetic flux between the windings of adjacent channels, so crosstalk cannot be avoided.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the problem of p-stoke between channels and to provide a single-tally transformer.

Briefly stated, the present invention divides the magnetic material constituting the rotor and stator into a plurality of parts by interposing a non-magnetic material layer between the channels, and assigns each channel a respective one.
Moreover, the plurality of divided magnetic bodies are formed into concave or convex shapes, and the magnetic bodies of the opposing rotor or stator are fitted with gaps, and windings are applied to these concave and convex parts. It is a rotary transformer. The present invention substantially prevents crosstalk between channels by interposing a non-magnetic layer between the magnetic materials, and the magnetic field generated by the winding for each channel is directed toward the magnetic material around which it is wound and the magnetic field opposing it. The cause of crystal talk is further eliminated by having an intricate structure with convexes and convexes so that it is localized only to the magnetic material that causes crystallization. Thus, the four-cell transformer of the present invention has high performance.

The invention will now be described in detail in conjunction with the drawings.

FIG. 2 shows a vertical cross-sectional view of an actual coaxial rotary transformer 1, in which 5 is a stator and 6 is a stator (depending on the application, 5 and 6 may be used as a stator). The stator 5 includes annular magnetic bodies a, arranged at predetermined intervals around a fixed cylindrical body 7 made of a ceramic material such as alumina or crystallized glass.
, 8. (6 or more depending on the application). Magnetic material B
S,81 can be manufactured from materials such as high permeability sintered ferrite and permalloy. For example, it is possible to stack sheets of ferrite powder paste punched into annular shapes and fire them, to mold them using a powder press and fire them, or to stack them using a printing method and then fire them. Then, the stator can be manufactured by fitting and bonding the annular body thus obtained into a predetermined position of the non-magnetic cylindrical body 7.

Next, the rotor 6 is made of a current magnetic material 91. which has a U-shaped cross section.
91 and a nonmagnetic layer 10 interposed between them. The ring-shaped magnetic body 91.9g is made of high magnetic permeability ferrite, permalloy, etc., and can be manufactured by the same method as described for the stator. The nonmagnetic layer 1o may be made of alumina, crystalline glass, or silicone rubber, and is bonded to the annular magnetic body using an adhesive such as a synthetic resin or by baking.

Stator and rotor annular magnetic bodies 81.81 and 9.
,? As shown in the figure, one side is formed in a convex shape and the other side is formed in a concave shape, and the shapes and dimensions are such that these concave and convex portions fit together with a constant gap.

A winding 111 is provided on the outer peripheral surface of the convex annular magnetic body 81.81.
．． 11'l is wound, and a concave annular magnetic body 9
．． ．． 9. Winding wires 121 and 121 are wound around the inner circumferential surface of.

According to the above uneven structure, the volume @11. Or, the magnetic flux generated by 12.degree. is restricted to the inside of the magnetic body 81. It is possible to increase the bond with Similarly, the coupling of volume 1!111.121 also increases. This also means that the coupling between neighboring channels is reduced. Furthermore, since each annular magnetic body is separated by a non-magnetic layer between adjacent channels, the cause of crosstalk is further reduced. FIG. 3 shows an example in which the present invention is applied to a disk type rotary transformer. The stator 20 has a fixed shaft 22 supporting a non-magnetic disc 23 made of alumina, crystalline glass, etc., and two annular magnetic bodies 24 concentrically arranged on the surface of the non-magnetic disc 23. ．． Fix 24t,
251.25 windings on their top surfaces! are fixed respectively. The four-piece 21 is rotatably supported by a stator shaft 22 by suitable bearing means, and has a ring-shaped non-magnetic layer 2.
Concentrically arranged annular magnetic bodies 26, . 2
6. Each of the annular magnetic bodies 263, 26 has a square U-shape, and a winding 271, 27* is fixed to each recess thereof. A reinforcing plate 2 can be used on the top surface of the sweater.

Moreover, the magnetic body 24 of the stator. ．． 24. and the convex part of
Evening magnetic material 26. ．． 26. The recesses are manufactured in a shape and size that fit each other with a certain gap between them. The method of manufacturing these quadruplets and stators may be the same as in the example shown in FIG. For example, stator 20
In this method, a high permeability magnetic material, such as Fephite sintered material, is pasted on the surface of an alumina disk, silver foil is pasted on top of it, and windings are formed by etching, or these parts are printed using a printing method. It is clear that the rotary transformer according to this embodiment has the same effect as the above-mentioned example.

[Brief explanation of the drawing]

1. FA is a cross-sectional view of a conventional rotary transformer, FIG. 2 is a cross-sectional view of a rotary transformer according to a first embodiment of the present invention, and FIG. 3 is a cross-sectional view of a rotary transformer according to a second embodiment of the present invention. The main parts in the figure are as follows. 5.20 Nischi Taro, 21:0-Tough: Non-magnetic cylindrical body ai, 8. : Annular magnetic body 9m, 9t: Annular magnetic body 1 10: Non-magnetic layer 111.111.121.12! ': Winding wire 26: Non-magnetic disk 24, . 24. : Annular magnetic material 251.252: Winding wire 26: Non-magnetic material layer 261.26! 'Annular magnetic body 271.271' winding

Claims (2)

[Claims] (1) A rotary transformer in which a plurality of windings are provided on opposing surfaces of a rotor and a stator, which are supported so as to rotate relative to each other, so that electromagnetic coupling occurs between opposing pairs of windings. A rotary transformer comprising a high magnetic permeability magnetic material whose opposing surfaces are formed as concave and convex surfaces that fit into each other at a predetermined interval. (2) The four-tally transformer according to item 1, wherein the magnetic bodies of each of the theta and stator are divided in the middle between the plurality of windings, and a non-magnetic body is interposed therebetween.