JPS63268115A - Rotary head device - Google Patents

Abstract

PURPOSE:To contrive a low cost by arranging a first core and a first coil at the rotary drum to rotate in a single body with a shaft and arranging a second core and a second coil at the fixed drum not to rotate and constituting a rotary transformer of these. CONSTITUTION:A magnetic flux A to flow from a magnetic gap 53 into a core 51 flows at the core 51, flows out from the core 51 and flows B into a protruding part 31 as a bridge core. Next, a magnetic flux B flows in the protruding part 31, flows out from the joining surface of a core 52 and flows C into the core 52. Next, a magnetic flux C flows in the core 52 and flows D from a magnetic gap 53. Into the magnetic flux B path to flow out from the core 51 and flow into a bridge core 31, a loop 41 is arranged and into the magnetic flux C path to flow out from the bridge core 31 and flow into the core 52, a loop 42 is arranged. Consequently, the electromotive force to occur in loops 41 and 42 is added and a current flows at a coil 32. Since for the oil 32, the extended tip comes to be a coil 13, the current of the coil 32 flows at the coil 13 as it does and the corresponding current is outputted from a coil 14 to constitute the rotary transformer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotary head device suitable for use in a magnetic recording/reproducing device typified by R-DAT.

[Summary of the invention]

In the present invention, a protrusion is formed on the core constituting the rotor of the rotary transformer, and the head is fixed to the protrusion.

The height position of the head is adjusted by pressing the protrusion with a screw.

[Background technology]

Figure 12 shows a conventional video tape recorder, R-DAT.
This figure shows the configuration of a rotary head device of a magnetic recording/reproducing device such as . In the figure, 1 is a shaft rotated by a motor (not shown), and a flange 2 is fixed thereto.

3 is a rotating drum, which is fixed to the flange 2 with washers 5 and screws 4. 6 is head, dime 7
is fixed. The dime 7 is fixed to the rotating drum 3 together with a dime base plate 19 by screws 8 and washers 9.

Reference numeral 10 denotes a screw, which is screwed onto the rotating drum 3.

By rotating this screw 10 and moving it forward and backward, it is possible to press the dime 7 and adjust the height position of the head 6. The flange 2 has a core 11 with coils 13 and 15.
is fixed with adhesive. Coil 14 facing core 11
．． A core 12 having a diameter of 16 is fixed to a stationary drum 17. The fixed drum 17 is attached to the shaft 1 so as not to rotate integrally therewith. Core 11. The coil 13.15 connects the rotor, and the core 12 and the coil 14
．． 16 constitutes a stator, and both constitute a rotary transformer. The head 6 is electrically connected to the coil 13 (or 15) via a dime board 19 or a relay board 18.

FIG. 13 shows the structure of the head 6. The pair of cores 21 are arranged to face each other so that one end forms a magnetic gap 22 . Further, the other ends 23 of the cores 21 are connected to each other, and the cores 21 form a closed magnetic path. Furthermore, a coil 24 connected to the coil 13 (or 15) is wound around the core 21.

When the shaft 1 rotates, the rotating drum 3, head 6, core 11. Coils 13.15 rotate together. Magnetic flux from a magnetic tape (not shown) flows into one core 21 from the magnetic gap 22, flows to the other core 21, and flows out from the magnetic gap 22.

Therefore, an electromotive force is generated in the coil 24, and a signal flows to the coil 13 (or 15). This reproduced signal B is output to a circuit (not shown) via the other coil 14 (or 16) constituting the rotary transformer.

Although not shown, there is another opening 180 degrees apart from the head 6.
Two heads are attached, and the reproduction output thereof is similarly supplied to an external circuit via coil 15 (or 13) and coil 16 (or 14).

When recording a signal, current flows through a path opposite to that described above.

[Problem that the invention seeks to solve]

In this way, in the conventional rotating head device, the head 6 is fixed to the dime 7, and the dime 7 is fixed to the rotating drum 3, which not only requires a large number of parts and increases the cost, but also increases the cost of the device. The disadvantage is that it becomes larger.

Therefore, the present invention aims to reduce the number of parts, thereby realizing cost reduction and miniaturization.

[Means for solving problems]

The present invention provides a rotating head device including a rotating drum attached to rotate integrally with a shaft, a first core fixed to the rotating drum, and a first coil disposed on the first core. a fixed drum mounted so as not to rotate integrally with respect to the shaft; a second core fixed to the fixed drum; a second coil disposed on the second core; a protrusion provided in the core of the
It is characterized by comprising a head fixed to the protrusion and a screw that presses the protrusion.

[Effect]

A first core is fixed to a rotating drum that rotates integrally with the shaft, and a first coil is disposed on the first core. Further, a second core is fixed to the fixed drum that does not rotate integrally with the shaft, and a second core is fixed to the fixed drum that does not rotate integrally with the shaft.
coils are arranged. A rotary transformer is configured by the first core, the first coil, the second core, and the second coil. A protrusion is formed in the first core, and the head is fixed to the protrusion. The height of the head is adjusted by pressing the protrusion with a screw.

〔Example〕

The present invention will be described in detail below with reference to the drawings.

In the following figures, the same reference numerals are given to the parts corresponding to those in the above case, and detailed description thereof will be omitted.

FIG. 9 and FIGS. 2 and 3 show a first embodiment of the invention. In this embodiment, a protruding portion 31 that protrudes toward the outer periphery is integrally molded onto a core 11 constituting a rotor of a rotary transformer.

A part of the coil 13 of the rotary transformer is extended as it is to form a coil 32 constituting the magnetic head. Similarly, a coil 33 is formed in the coil 15 of the other channel.

The coils 32 , 33 are placed on the projection 31 .

Therefore, in this state, the coil 13.15 as the rotary transformer and the coil 32.33 as the magnetic head are located on substantially the same plane.

Coil 32 (as well as coil 33) has two loops 41, 42 as shown in FIG. The loops 41 and 42 are wound so that when current flows through the coil 32, the magnetic flux output from one loop and the magnetic flux output from the other loop are in opposite directions in FIG. A head chip 50 as shown in FIGS. 4 to 6 is bonded and fixed onto the coils 32 and 33 as shown in FIG. 3.

The head chip 50 is composed of a pair of cores 51 and 52 made of ferrite or other magnetically permeable material.
1.52 are arranged to face each other so that a part thereof constitutes a magnetic gap 53. However, the portions of the cores 51 and 52 other than the magnetic gap 53 are sufficiently separated to prevent magnetic flux from flowing directly between them. In order to more effectively prevent this direct inflow and outflow of magnetic flux, a member 54 made of a non-magnetic material such as glass, metal, ceramic, etc. is filled between the cores 51 and 52 as necessary (fourth
Alternatively, a conductive plate 61 made of metal, foil, conductive paint, etc. is arranged on the core 51, 52 to reduce upward leakage of magnetic flux due to eddy currents (Fig.
(FIG. 5), the head chip 50 is attached with a conductive adhesive 62.
A similar effect can be obtained by adhering and fixing the coil 32 onto the protrusion 31 (FIG. 6).

Therefore, as shown in FIG.
The magnetic flux (A) flowing into the core 51 flows through the core 51.

The protrusion 31 flows out from the core 51 and serves as a bridge core.
(B), magnetic flux flowing from the protrusion 31 (B)
flows inside the protrusion 31 and flows out from the joint surface of the core 52,
Flowing into the core 52 (C), magnetic flux flowing into the core 52 (
C) flows through the core 52 and flows out of the magnetic gap 53 (D); magnetic flux flows out of the core 51 and flows into the protrusion (bridge core) 31 (B); a loop 41 is arranged in the path; 31 and flows into the core 52 (
C) A loop 42 is placed in the path. - Therefore, the electromotive forces generated in the loops 41 and 42 are added, and a current flows through the coil 32. Since the extended end of the coil 32 is the coil 13, the current in the coil 32 flows directly to the coil 13, and a corresponding current is output from the coil 14 forming the rotary transformer.

Similarly, the signal of the coil 33 of the other channel is output from the coil 15.

In the figure, the number of turns of the coils 13, 14, 15, 16, 32, and 33 is 1 turn, but it is of course possible to have 2 turns or more. Further, these coils can be formed using ordinary conductive wires, but since so-called winding work is not required, they can also be formed by printed coils, metallization, sheet metal punching, etc. In the case of the latter three, there is no need for wiring work.

FIGS. 7 and 8 show a second embodiment. In this embodiment, the coils 32 and 33 constituting the two heads are connected in series, and the rotary transformer has only one channel (only the coil 13). As a result, the current flowing through the coil 32 also flows through the coil 33. However, in R-DAT, 1
The two rotating heads, spaced 80 degrees apart, contact the magnetic tape only 90 degrees each, ensuring that when one is in use the other is not, thus reducing the human power of one channel of rotary transformer. By dividing, signals can be recorded and reproduced in the same way as in the case of two channels. In this way, the diameter of the rotary transformer and, therefore, the diameter of the rotating drum 3 can be made smaller.

The second embodiment is less efficient than the first embodiment.

However, there are practically no problems particularly when recording and reproducing signals digitally, such as with R-DAT.

The method of connecting two rotating heads in series is to connect the coil 32.
．． Of course, the present invention can also be applied to the case where 33 is configured as shown in FIGS. 2 and 3. FIG. 1 shows a cross-sectional view of such a configuration.

In this embodiment, a rotating drum 3 is directly attached to the shaft 1, and a core 11 is bonded and fixed to the rotating drum 3 with an adhesive. Then, by moving the screw 1o forward and backward, the core 11 is pressed, and the head chip 5
0 height position can be adjusted. The distance between the cores 11 and 12 that make up the Tali transformer is usually 40μ.
m to about 50 μm, whereas the head height adjustment distance is about 5 μm to 10 μm, so even if the head height is adjusted, a sufficient clearance between the cores 11 and 12 is ensured. With such a configuration, the number of parts can be significantly reduced.

Figures 10 and 11 are similar to Figure 9 and Figures 2 and 3.
An embodiment is shown in which a groove 81 is formed laterally in the protrusion 31 of the embodiment shown in the figure. This embodiment has the advantage that since the stress caused by the screw 10 is concentrated in the groove 81, the clearance D between the cores 11 and 12 hardly changes even if the height of the head is adjusted, and the characteristics as a rotary transformer do not deteriorate. have

The head height adjustment mechanism of the present invention can also be applied to a conventional magnetic head having a structure in which a coil is wound around a core. In this case as well, the number of parts can be reduced compared to the conventional case, the rotary head device can be made more compact, and costs can be reduced.

〔effect〕

As described above, the present invention relates to a rotary head device.

a rotating drum attached to rotate integrally with respect to the shaft; a first core fixed to the rotating drum; a first coil disposed on the first core; a fixed drum attached so as not to rotate; a second core fixed to the fixed drum; a second coil disposed on the second core; and a protrusion provided on the first core. Since it includes a head fixed to the protrusion and a screw that presses the protrusion, the number of parts can be reduced and the cost and size can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the rotating head device of the present invention, FIG. 2 is a perspective view of its coil, FIG. 3 is an assembled perspective view of the head chip and coil, and FIG. 4 is a perspective view of the head chip. 5 and 6 are assembled perspective views of the head chip and the conductive member, FIG. 7 is a perspective view of the rotor, and FIG. 8 is a perspective view of the coil. FIG. 9 is a perspective view of a rotor according to another embodiment, and FIG. 10 is a perspective view of still another embodiment of the rotor. FIG. 11 is a sectional view of the rotary head device, FIG. 12 is a sectional view of the conventional rotary head device, and FIG. 13 is a plan view of the head. 1...Shaft 2...Flange 3...Rotating drum 4...Screw 5...Washer 6...Head 7...Dime 8...Screw 9...Washer 10... Screws 11, 12...Core 13 to 16...Coil 17...Fixed drum 18...Relay board 19...Dime board 21...Core 22...Magnetic gap 23...End part 24... Coil 31... Projection 32.33... Coil 41.42... Loop 50... Head chip 51.52... Core 53... Magnetic gap 54... Member 61 ...Conductive plate 62...Adhesive 71...Groove 72, 73...Loop 81...More than groove

Claims (1)

[Claims] a rotating drum attached to rotate integrally with respect to the shaft; a first core fixed to the rotating drum; a first coil disposed on the first core; a fixed drum attached so as not to rotate integrally with the fixed drum; a second core fixed to the fixed drum; a second coil disposed on the second core; and a second coil disposed on the first core. What is claimed is: 1. A rotary head device comprising: a protruding portion, a head fixed to the protruding portion, and a screw for pressing the protruding portion.