JPS63232406A - Rotary transformer - Google Patents

Abstract

PURPOSE:To miniaturize a rotary transformer without deteriorating transmission gains and increasing a low-path cut-off frequency by forming coils on the mutually opposed magnetic surfaces of magnetically coupling primary and secondary each body by conductive materials through a non-magnetic electric insulating material. CONSTITUTION:Coils 5-8 for each body on the primary side 1 and the secondary side 2 are shaped onto magnetic surfaces through insulators 9-12 through a technique such as printing, sputtering, steam, etc. In a rotary transformer having such constitution, the coils need not be wound, and the winding width of the coils can be reduced. Accordingly, the size of groove width can be scaled down, thus ensuring performance, inductance and a coupling efficiency at the time of operation at fixed values even when the rotary transformer is miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rotating transformer commonly used in magnetic recording and reproducing devices.

BACKGROUND OF THE INVENTION In recent years, magnetic recording and reproducing devices have become smaller in size at a remarkable rate, and the components constituting these devices are also required to be smaller and have higher density. In particular, in recording and reproducing systems using rotating heads such as video tape recorders, the size of the device is limited by the size of the cylinder used, and the main volume of this cylinder is occupied by the internal rotating transformer. . Therefore, in order to miniaturize magnetic recording and reproducing devices, it is important to miniaturize the rotary transformer.

FIGS. 4, B, and Cj respectively show a side view, a plan view, and a sectional view of a rotary transformer as a conventional example. 1 is a primary main body of a rotating transformer made of magnetic material; 2 is a secondary main body; 3 is a gap that separates the primary and secondary sides of the rotating transformer; 4 is a magnetic surface that is magnetically coupled through the gap; 5; 6 marks the signal 7Xl
Alternatively, the primary coils 7 and 8 are secondary coils for reproducing signals.

A magnetic head is connected to the beginning and end of each of the primary coils 5 and 6, and the secondary coils are connected to each other.

An amplifier for signal reproduction is connected to the start and end terminals of each of the circuits 8 and 8.

In such a configuration, the primary body 1 of the rotary transformer rotates, and the reproduction signal from the magnetic head is transmitted to the primary coil 5.
6, a magnetic flux is generated through the magnetic surface 4 of the air gap 3 between the rotary transformer 1.2. This magnetic flux generates an induced voltage in each of the secondary coils 7 and 8 installed facing each other, and the reproduction output can be transmitted to the amplifier without rotating the secondary main body 2. Similarly, the recording signal is applied to each of the secondary coils 7.8, an induced voltage is generated in each of the primary coils 6.6, each signal flows to the magnetic head, and is recorded on the magnetic tape. can do.

Problems to be Solved by the Invention However, in order to miniaturize such a rotating transformer, the outer dimensions of the coils 5', 6, 7.8 must be reduced,
It is necessary to change the width of the groove in which these are installed. As a result, in order to obtain the same performance as in the past, the wire diameter of the coil must be reduced, resulting in problems such as wire breakage, difficulty in winding the coil, and deterioration of productivity during assembly.

The present invention solves the problem of deterioration in productivity caused by downsizing a rotary transformer.

Means for Solving the Problems In order to solve the problems with the conventional technology, the rotary transformer according to the present invention uses printing, sputtering, vapor deposition, or other techniques for the coils of each main body on the primary and secondary sides. It is characterized in that it is formed on a magnetic surface with an insulating material interposed therebetween.

Effect □ In a rotary transformer with such a configuration, there is no need to wind a coil, and the winding width of the coil can be reduced. Therefore, the groove width can be reduced, and even if the rotary transformer is downsized, it is possible to maintain predetermined values for performance, inductance, and coupling coefficient during operation.

Embodiment As an embodiment of the present invention, FIGS. 1, B, and C show a side view, a plan view, and a sectional view of a rotary transformer, respectively. In Fig. 1, 1 is the primary body of the rotary transformer, 2 is the secondary body of the rotary transformer, 3 is the gap separating the primary and secondary bodies of the rotary transformer, and 4 is the gap that separates the primary and secondary bodies of the rotary transformer. A magnetic surface for magnetic coupling, 5.6 is a primary coil formed for marking or reproducing a signal, and 7.8 is a secondary coil formed for printing or reproducing a signal. 9,10゜11.12 is the primary coil 6.6 and the secondary coil 7.8
and a primary body 1° and a secondary body 2 made of magnetic material.
It is an insulating material that insulates magnetic and electrical conduction.

In such a configuration, the operation of connecting the magnetic head and the recording/reproducing amplifier will be explained. During reproduction, the signal current generated from the magnetic head is applied to each of the secondary coils 6.6 and magnetically coupled to each of the opposing secondary coils 7.8 via the magnetic surface 4 of the air gap 3. A signal voltage is induced and transmitted to a regenerative amplifier. During recording, a signal from the recording amplifier causes a recording current to flow into the secondary coils 7 and 8, induces a signal voltage in the magnetically coupled primary coils 5 and 6, and causes a current to flow through the magnetic head, causing the magnetic tape to recorded in

In this way, the rotary transformer converts an electric signal into magnetic flux, which is then reconverted and used as an electric signal. The performance of this rotary transformer is determined by the self-inductance L1 of the primary coil. The low cutoff frequency f is determined by the loss resistance R1, the winding ratio n of the primary and secondary sides, the coupling coefficient k, the self-inductance Lh of the magnetic head, and the loss resistance Rh. The gain G in the middle range is. Therefore, the self-inductance L of the primary coil
By increasing the value of 1, the cutoff frequency is lowered and the gain G is increased. Primary side self-inductance L
1 becomes μ08N2 L1~□ from the number of turns N, the magnetic permeability 11o in air, the length g of the gap, and the area S of the opposing magnetic surfaces. From this, in the rotating transformer of this example,
If the external dimensions are the same as the conventional one, the self-inductance can be doubled by increasing the number of turns N on the primary side.

Furthermore, by making the self-inductance the same, it becomes possible to dramatically downsize the rotary transformer.

A specific example of the configuration of the primary and secondary coils of the present invention is shown in the second section.
As shown in Fig. 3.

Figure 2 is an enlarged view of the grooves on the opposing magnetic surfaces, 1 is the primary side of the rotary transformer, 2 is the secondary side of the rotary transformer, and 3 is the air gap separating the primary and secondary sides of the rotary transformer. , 4 is a magnetic surface magnetically coupled through an air gap, 10.11 is a non-magnetic electrical insulating material formed at the bottom of the groove of the magnetic surface, and 6.8 is formed on the insulating material 11.10. It is a spiral coil.

Figure 3 is an enlarged view of the grooves on the opposing magnetic surfaces, 1 is the primary side of the rotary transformer, 2 is the secondary side of the rotary transformer, and 3 is the air gap separating the primary and secondary sides of the rotary transformer. , 4 is a magnetic surface that magnetically couples through an air gap, 10.11 is a non-magnetic electrical insulating material laminated in the groove of the magnetic surface, and 6.8 is an insulating material 1
This is a coil made of conductive material alternately laminated with 0.11.

By forming the coil as described above, the number of turns can be increased, making it possible to create a small-sized rotating transformer.

Effects of the Invention The present invention forms the primary and secondary coils on magnetic surfaces with an insulator interposed therebetween, thereby eliminating the need to wind wires to form coils, making it possible to reduce the winding width. This makes it possible to downsize the rotary transformer without deteriorating the transmission gain or increasing the low cutoff frequency.

Therefore, by using the rotary transformer of the present invention, the magnetic recording/reproducing device itself can be made smaller, and its characteristics will not deteriorate due to the smaller size.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the rotary transformer of the present invention, where M is a side view, B is a plan view, C is a sectional view, and FIG. 2 is a groove on a magnetic surface showing the configuration of a coil of the rotary transformer of the present invention. FIG. 3 is an enlarged sectional view of the groove portion of the magnetic surface showing the configuration of the coil of the rotary transformer of the present invention; FIG. 4 is an enlarged sectional view of the groove portion;
C is a side view, a plan view, and a sectional view showing a conventional rotary transformer. 1...Primary body, 2...Secondary body, 3
... air gap, 4 ... magnetic surface, 5, 6 ...
...Primary coil, 7.8...Secondary coil,
9,10,11.12...Insulating material. Name of agent: Patent attorney Toshio Nakao and 1 other person/-
/ Combined 1 (F3) (C) Figure 2 @ Figure 3 10 1° Figure 4 (Han? (S6 δ 41)

Claims (4)

[Claims] (1) A rotary transformer characterized in that a coil is formed of a conductive material on the opposing magnetic surfaces of the primary and secondary main bodies that are magnetically coupled through a non-magnetic electrical insulating material. (2) The rotary transformer according to claim 1, wherein the coil is formed in a spiral shape with an insulating material interposed in the groove. (3) The coil is formed by laminating a conductive material in the groove with an insulating material interposed therebetween.
Rotating transformer as described in section. (4) The rotary transformer according to claim 1, wherein the coil is formed in a spiral shape through a non-magnetic electrical insulating material without forming a groove on opposing magnetic surfaces.