JPS599906A - Rotary transformer - Google Patents

Abstract

PURPOSE:To attain a transformer with small crosstalk and high mechanical rigidity by a construction wherein a rotary transformer is composed of plate-like conductors each formed with one or more concentric projections, and annular cores having one or more windings concentrically fitted therein and being mounted to the conductor on both sides of each projection. CONSTITUTION:Disc-like conductors 15, 16 are formed of brass, and concentric projections 15-1, 15-2 are formed on the conductor 15. A rotary shaft 1 is fitted to penetrate through the projection 15-2 and to be fixed thereto. On both sides of the projection 15-1 of the disc-like conductor 15, an annular first rotary-side core 2-1 is fixed between the projections 15-1 and 15-2 using adhesives and an annular second rotary-side core 2-2 is fixed on the outer peripheral side of the projection 15-1 similarly using adhesives. Next, windings 4, 5 constituting one group are respectively fitted in two grooves formed in the first rotary-side core 2-1, while windings 6, 7 constituting the other group are respectively fitted in grooves formed in the second rotary-side core 2-2. After constituting the conductor 16 in the substantially same manner, these conductors are combined with stationary-side cores 3-1, 3-2 being fitted to the conductor 16.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flat plate type rotary transformer used for signal transmission between a rotary magnetic head of a magnetic recording/reproducing device for video signals and the like and an electric circuit such as an amplifier.

In the case of a conventional flat plate rotary transformer, for example, in the case of a 4-channel type, it is fixed concentrically to a rotating shaft 1 as shown in FIG. The disk-shaped stationary side core 3 is freely penetrated through the disk-shaped stationary side core 3, and the rotating side winding 4.5.
6 and 7, and the stationary side windings 8, 9, respectively installed in the grooves of the stationary side core 3 provided opposite to the grooves of the rotating side core 2.
10 and 11. Further, the windings 4 and 5 are set as one group, and the windings 6 and 7 are set as another group, and the rotating side iron core 2 between the windings 5 and 6 and between the windings 9 and 10 is
Further, annular short rings 12 and 13 are separately attached to the stationary side iron core 3 to reduce crosstalk between one group and another group.

However, the crosstalk in the case of a conventional rotary transformer equipped with a short ring as described above is as shown in Fig. 2.
It was -65 dB at 3 MHz and about -50 dB at 5 MHz. In addition, in Figure 2 (f)
is the signal (assumed to be OdB) to winding 9 of the rotating transformer in Figure 1.
(b) is the output that appears in the winding 6 due to crosstalk at this time.

In addition, in order to reduce the above-mentioned crosstalk, the iron core 2.3 of the rotating transformer shown in Fig. 1 is divided into the inner and outer parts at the short ring part, and the short ring is placed between the inner and outer annular cores. I tried to construct it by gluing it together. When a rotary transformer was configured in this manner, crosstalk was improved, but mechanical strength could not be maintained due to the difference in thermal expansion coefficient between the annular core and the short ring due to temperature rise during use.

The present invention has been made in view of the above, and provides a mechanically strong flat plate rotating transformer that can reduce crosstalk to about -80 dB or less with a simple configuration and eliminates the above drawbacks. The purpose is to provide

This purpose consists of a plate-shaped conductor on which one or more protrusions are formed concentrically, and an annular iron core on which at least one winding is attached concentrically and attached to the conductor with the protrusion of the conductor in between. This is achieved by having the following.

The present invention will be explained below using examples.

FIG. 3 is a sectional view showing one embodiment of the present invention.

In FIG. 3, 15 and 16 are disc-shaped conductors made of brass or the like. The disc-shaped conductor 15 has concentric protrusions 1.
5-1 and 15-2 are formed, the rotation shaft 1 is passed through the projection 15-2, and the rotation shaft 1 is connected to the projection 15-2.
is fixed.

On the other hand, an annular first rotating side iron core 2-1 is fixed to the disc-shaped conductor 15 by narrowing the protrusion 15-1 between the protrusion 15-1 and the protrusion 15-2 with adhesive or the like. , protrusion 15-1
An annular second rotating side iron core 2-2 is fixed to the outer circumferential side of the rotor with an adhesive or the like.

In addition, windings 4 and 5 constituting one group are respectively installed in the two grooves provided in the first rotating side iron core 2-1, and the windings 4 and 5 forming one group are respectively installed in the two grooves provided in the first rotating side iron core 2-1. The windings 6 and 7 constituting the other group are respectively mounted in the grooves.

On the other hand, the disc-shaped conductor 16 also has protrusions 1 like the conductor 15.
Protrusions 16-1 and 1 opposite to 5-1 and 15-2
6-2 are formed concentrically, and the protrusions 16-2
The rotating shaft 1 is rotatably inserted through the hole. On the other hand, an annular first stationary side iron core 3-1 is fixed to the disc-shaped conductor 16 with the protrusion 16-1 between the protrusion 16-1 and the protrusion 16-2 with adhesive or the like. An annular second stationary side iron core 3-2 is fixed to the outer peripheral side of the protrusion 16-1 with adhesive or the like. The first stationary side core 3-1 has windings 8 and 9 each constituting one group installed in a groove provided opposite to the groove of the first rotating side core 2-1. Second
Windings 10 and 11 constituting the other group are similarly attached to the stationary side iron core.

Further, the lead wires A, B, C and D of the windings 4.5.6 and 7 are drawn out through the plate-like part of the conductor 15, and the drawn wires A1 of the windings 8.9.10 and 11 are drawn out. ,Bl,
C1 and Dl extend through the plate-like portion of the conductor 16.

In the above state, the rotary transformer according to the embodiment of the present invention differs from the conventional rotary transformer shown in FIG. , and a conductor plate electrically connected to the conductor is fixed to the outer surface, and the function as a rotary transformer is exactly the same.

In other words, the windings 4, 8.5, and 9 are connected to the windings 6, 10.7, and 11 by the electromagnetic induction effect in cooperation with the iron core 2-1.3-1.
Signal transmission is performed by electromagnetic induction in cooperation with the iron core 2-2, 3-2.

However, the rotating side iron cores 2-1 and 2-2 and the stationary side iron core 3 forming the magnetic circuit of the first group and the second group
-1 and 3-2 are separated by protrusions 15-1 and 16-1, and the group windings are electrostatically shielded by connecting the conductor 15.16 to a predetermined potential point, such as a ground point. Also windings 4, 5, 6 and 7 and lead wires A, B, ,C
and D are electrostatically shielded and winding 8.9.10
and 11 and the lead wires A1, B1, C1 and Dl are also electrostatically shielded. In this state, we measured the crosstalk between the windings in the first group and the windings in the second group, and as shown in Figure 4, the crosstalk was between 0.1 M, Hz and 5 MHz. JFl is always improved by more than 0 dB than the conventional case, and 5M
Even between Hz and 1QMHz, there was always an improvement of more than 20 dB.

Note that (a) and (b) in FIG. 4 are the outputs generated at the winding 5.6, as in the case of FIG.

Also, the protrusions 15-2 and 1G-2 are omitted, and the iron core 2-
The iron core 3-1 may be fixed to the rotating shaft 1 by the inner circumferential surface of the iron core 3-1, and a predetermined gap may be provided between the inner circumferential surface of the iron core 3-1 and the rotating shaft 1.

Further, in one embodiment of the present invention described above, the drawer M
A, B, C, and D will be explained using the case where they are drawn out by penetrating the plate-like part of the conductor 15, and the case where the leader wires A1, B1, C1, and A are drawn out by passing through the plate-like part of the conductor 15. However, the lead wires C and I] were not taken out through the plate-shaped part of the conductor 15, and
and the rotating side iron core 2-2.
1 and Dl are not taken out through the plate-shaped part of the conductor 16, but the plate-shaped part of the conductor 16 and the second stationary side iron core 3-2 are removed.
You may also pull it out along the line between. The crosstalk in this case is the same as in the embodiment of the present invention described above.

Further, the lead wire entry and B are connected to the protrusion 15- of the conductor 15.
1 through the conductor 150 and drawn out along between the disk portion and the second rotating side iron core 2-2, and the lead wires A1 and B1
may be passed through the protrusion 16-1 of the conductor 16 and drawn out between the disk portion of the conductor 160 and the second stationary side iron core 3-2. In this case, crosstalk is somewhat lower than in one embodiment of the present invention.

In addition, although the above explanation is based on an example in which four windings forming four channels are divided into two groups, a similar structure can be created by providing a protrusion on a disc-shaped conductor to separate the windings forming each channel. The same applies to cases.

In addition, as shown in FIG. 3, the rotating side iron cores 2-1 and 2-
The surface of the protrusion 15-1 is recessed from the surface of the stationary side cores 3-1 and 3-2, and the surface of the protrusion 15-1 is recessed from the surface of the stationary side cores 3-1 and 3-2. This is to prevent the brass part of the protrusion 15-1 from digging into the abrasive material and being unable to be polished due to the difference in hardness when polishing the surface of the stationary side iron core 3-2. This is to prevent the same problem when polishing the surfaces of Nos. 1 and 3-2.

As explained above, according to the present invention, since a ring-shaped iron core having at least one or more windings concentrically attached to the protrusion formed on the plate-shaped conductor is attached to the conductor with the interstices X7,
Mechanical strength can be maintained even when the temperature rises due to use.

Additionally, since the windings installed on different cores are separated by a protrusion and the conductor is connected to a predetermined potential point, the windings installed on different cores are electrostatically shielded. Crosstalk between lines is reduced.

In addition, it is easy to draw out part or all of the lead wires of the windings through the conductor, and in this way, the windings attached to different cores are electrostatically shielded, and the windings Both the lead wire and the lead wire can be electrostatically shielded, and crosstalk between windings attached to different iron cores is improved.

Further, when the present invention is used in a video signal magnetic recording/reproducing device, etc., a plate-shaped conductor may be connected to ground.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the configuration of a conventional flat plate rotary transformer. FIG. 2 is a diagram showing the crosstalk characteristics of the conventional flat plate rotary transformer shown in FIG. FIG. 3 is a sectional view showing the configuration of an embodiment of the present invention. FIG. 4 is a diagram showing crosstalk characteristics of an embodiment of the present invention. 1...Rotating shaft, 2-1 and 2-2 Rotating side iron core, 3
-1 and 3-2... Stationary side core, 4 to 11 windings, 1
5 and 16... conductor, 15-1 and 16-1...
・Protrusions, A-DXA1 to Dl...Leader lines. Figure 1 Figure 2 Figure 6 Figure 4

Claims (3)

[Claims] (1) A flat plate-type rotary transformer, in which a plate-shaped conductor having one or more protrusions concentrically and equipped with a lead-out means, and at least one or more windings concentrically attached. and an annular iron core attached to the conductor with a protrusion of the conductor interposed therebetween, and the conductor is connected to a predetermined potential point. (2) The rotary transformer according to claim 1, wherein the lead wire lead-out means is a through hole provided in the conductor. (3) The rotary transformer according to claim 1, wherein the surface of the protrusion is recessed relative to the surface of the iron core.