JPS6236264Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a rotary transformer, particularly a multi-channel rotary transformer, and more particularly to a shield structure that reduces crosstalk between channels.

Figure 1 is a longitudinal cross-sectional view of this type of rotary transformer, where 1 is a rotary core, 2 is a stator core,
3 is the ch ₁ rotor side coil, 4 is the ch ₂ rotor side coil, 5 is the ch ₁ stator side coil, 6 is the ch ₂ stator side coil, 7 is the hole provided to pull out the coil, 8 is the hole provided to pull out the coil. A conductive thin film shield formed in an annular shape, 9 a support plate for fixing the stator core,
10 is a rotation shaft for rotating the rotor core.

This type of rotary transformer reduces crosstalk between channels by annularly depositing a conductive thin film shield 8 on both or one of the rotary core surface and the stator core surface. In the structure in which an annular thin film shield 8 is provided on the plane of this polished core,
Because the gap between both cores must be set to a small value of several tens of micrometers or less, the thin film shield is often damaged by mistake during assembly and adjustment, and the thickness of this thin film shield is about 1 micrometer. Because it is extremely thin, the thin film shield, which was formed in a continuous ring shape, may become locally thin, or in extreme cases, the ring may become discontinuous, significantly weakening the effect of reducing crosstalk between channels. Put it away.

This invention was made with the aim of eliminating the drawbacks of the conventional ones as described above.

Figure 2 is a vertical sectional view of one embodiment of this invention;
The figure is a plan view of the rotary core seen from the line in Figure 2, and Figure 4 is a sectional view of the rotary core seen from the line in Figure 3. 11 is formed on the surface between the channels of cores 1 and 2, respectively. It is a shallow ring-shaped depression with an arc-shaped cross section. Reference numeral 12 denotes a shield formed in an annular shape from conductive resin within this recess.

The width of this depression 11 is m between the coils 3 and 4.
The width is approximately the same as or narrower than this.
Furthermore, the thickness g of the conductive resin shield 12 is equal to the depression 1
It is formed to be shallower than the depth h of 1. Further, as shown in FIG. 2, the cores 1 and 2 are fixed to a rotating shaft 10 and a support plate 9, respectively, so as to face each other with a narrow gap of several tens of micrometers in between.

The rotary transformer configured in this way is
The problem of damage to the conductive thin film shield, which was a drawback of the conventional example, can be solved without sacrificing the performance (crosstalk characteristics) and the advantages of miniaturization of the conventional example, which simply adheres a thin film shield on a flat surface. The transformer can be easily assembled and adjusted.

In the above embodiment, a rotary transformer in which the ch ₁ and ch ₂ coils are taken out from separate holes is shown as an example, but the rotary transformer is not limited to this example. Even in rotary transformers that have grooves 13 formed on the core surface to take out the ch ₁ and ch ₂ coils from the same location,
The same effect can be obtained by filling the groove with the insulator 14 and forming an annular conductive resin shield thereon in the same way as in the above embodiment.

In other words, if you use a rotary transformer that has split grooves as shown in Figure 5 on the Roku drum side that has the middle diameter of the body, you can bundle the ch ₁ and ch ₂ coils in one place and take them out in the radial direction of the core. The coil can be disposed inside the body diameter, which is advantageous for downsizing.

The annular conductive resin shield 12 may be formed by adhering a conductive resin tape into the recess, or by applying conductive resin paint to the recess or by printing.

In this case, the cross-sectional shape of the depression is arc-shaped,
Since there are no corners, when pouring conductive resin into the recess, it is difficult for air to be drawn into the recess, resulting in a shield with good performance. Furthermore, when adhering the conductive resin tape, since the cross section is arcuate, the tape, which normally exhibits a curled state, can be adhered to the recess with better adhesion along the arc.

In the above embodiment, an example was shown in which the conductive resin shield was formed on both the rotor side and the stator side, but the conductive resin shield is not limited to this example, and may be formed only on either one. Further, the present invention is not limited to the case of two channels as in this example, but can be similarly applied to the case of multiple channels.

Note that a thickness of about 0.1 mm is sufficient for the conductive resin shield, but it goes without saying that the thicker the shield, the more effective it is.

Furthermore, it goes without saying that what has been described above can be similarly applied to a coaxial rotary transformer.

This idea consists of a rotary core fixed to a rotating shaft, a plurality of rotary coils coaxially arranged on one surface of this core, and supported so as to face the coil arrangement surface of the rotary coils with a gap in between. a stator core, a plurality of stator coils disposed on opposing surfaces of the core so as to face the plurality of rotary coils, and a core surface between these stator coils or a core surface between the rotary coils. It is equipped with an annular depression having an arcuate cross section formed on both or one of the surfaces, and a shield made of conductive resin within the depression, and on the polished core plane, Compared to a method in which a conductive thin film is applied in an annular shape, there is no risk of damaging the thin film during assembly and adjustment, and assembly and adjustment are easy, reducing costs and improving reliability.

Furthermore, since the recess in which the shield is formed has an arcuate cross section, a shield with better performance can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view of a conventional rotary transformer, Fig. 2 is a longitudinal sectional view of an embodiment of this invention, Fig. 3 is a plan view of the rotary core seen from the line of Fig. 2, and Fig. 4 is a longitudinal sectional view of a conventional rotary transformer. 3 is a sectional view taken along the line in FIG. 3, FIG. 5 is a plan view of a rotary core according to another embodiment, and FIG. 6 is a sectional view taken along the line in FIG. In the figure, 1 is a rotary core, 2 is a stator core, 5 and 6 are stator side coils, 11 is an annular depression, and 12 is a shield made of conductive resin.

Claims (1)

[Scope of utility model registration request] A rotary core fixed to a rotating shaft, a plurality of rotary coils coaxially arranged on one surface of the core, and a stator core supported so as to face the coil arrangement surface of the rotary coil with a gap therebetween. , a plurality of stator coils arranged to face the plurality of rotary coils on the opposing surface of the core, and a core surface between these stator coils and/or a core surface between the rotary coils. A rotary transformer that has an annular depression with an arcuate cross section formed on one side, and a shield made of conductive resin within the depression.