JPS6323790Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The present invention is a rotating magnetic head suitable for use in recording and reproducing low frequency signals such as VTR or audio signals using PCM, or recording and reproducing video signals. Regarding equipment.

Background Art and Problems Conventionally, in rotating magnetic head devices such as VTRs, the magnetic head (head chip) is attached to a rotating drum attached to a rotating shaft or a rotating plate formed as a rigid body. Another disadvantage is that the magnetic head has poor contact with the magnetic tape during use, deteriorating the responsiveness of the magnetic head-magnetic tape system, and particularly when the frequency of the recording signal is 5 MHz or higher, spacing loss becomes noticeable.

Purpose of the Invention The present invention is designed to eliminate the above-mentioned drawbacks, reduce spacing loss as much as possible, and simplify the overall configuration to increase mass productivity.

Summary of the invention In this invention, a head mounting plate made of a thin plate is provided, and a cutout is formed inward from the side edge of the head mounting plate. At least two bridges extending in a direction that intersects the straight line are formed so as to be integrated with the head mounting plate, and the bridge itself has elasticity. An electro-mechanical conversion element is attached across the bridge, and a magnetic head (head chip) is attached to the tip of this element.By making the bridge possess elasticity, the elasticity is applied to the magnetic head in a straight line passing through the center of rotation. This is to reduce spacing loss.

Embodiment An example of the apparatus according to the present invention will be described below with reference to the drawings. In the figure, 1 and 2 are an upper drum and a lower drum, and in this example, both are constructed as fixed drums. 3 is a rotating shaft, which is connected to a motor (not shown) and rotated at a rotational speed of, for example, 1800 rpm. 4 is a bearing. 5 is a disk attached to the rotating shaft 3, and a head mounting plate 6 is attached to this disk. 7 is its mounting screw.

The head mounting plate 6 can be formed into a circular shape as shown in FIG.
A center hole 8 is formed through which the position can be determined by inserting the hole 8 through the hole 8 and then fitting it. 9 is a through hole for the above-mentioned mounting screw 7.

This head mounting plate 6 is formed with a notch 10 cut inward from the side edge, and at least two bridges 11 are spanned within this notch 10. Each bridge 11 is configured to extend in a direction intersecting (orthogonal to in this example) a straight line 12 passing through the center of rotation of the head mounting plate 6, and is formed integrally with the head mounting plate 6.
It is itself designed to be elastic.

To explain an example of the manufacturing process of such a head mounting plate 6, a circular plate made of stainless steel with a thickness of approximately 0.1 mm to 0.5 mm is prepared, and a portion other than the notch 10 shown in FIG. Etching is performed by masking the portion (thus also masking the portion that will become the bridge 11). As a result, it is possible to easily obtain a shape in which two bridges 11 are sandwiched within the notch 10. The width W of the bridge 11 in this case is
You can choose around 0.1mm. Incidentally, since the notches 10 are actually separated by two bridges 11, they are shown with reference numerals 10a, 10b, and 10c, respectively, for ease of understanding. In this way, the head mounting plate 6 is formed of a thin disk, and the width W of the bridge 11 is also selected to be about 0.1 mm, so that the bridge 11 itself is imparted with elasticity.

An electro-mechanical conversion element 13 is mounted on the bridge 11 thus formed. A so-called bimorph element can be used as the electro-mechanical conversion element 13, and can be attached to the bridge 11 by adhesive. And although not shown,
Electrodes 14a and 14b on both sides of each of the pair of bimorph elements 13 are connected to a control circuit (not shown) through a slip ring (not shown).

A magnetic head (head chip) 14 is attached to the tip of each of the bimorph elements 13.
This can be attached by gluing. When attaching the magnetic heads 14 to the bimorph element 13, as shown in FIG. It is necessary to install them so that they have an angular spacing of .degree., that is, with accurate angular division. Also, the magnetic head 14 is attached to the bimorph element 13 in advance, and this is attached to the bridge 1.
When installing on 1, accurate angle division may be used.

According to such a configuration, since the magnetic head 14 is mounted on the bridge 11, it has elasticity in the radial direction of the head mounting plate 6, so that it makes very good contact with the magnetic tape during use. As a result, spacing loss can be reduced, and signals in high frequency bands can also be recorded and reproduced favorably. Further, by using the bimorph element 13, it is possible to bend the bimorph element 13 by applying a control signal from the control circuit, that is, the magnetic head 14 can be biased in the height direction. Therefore, conventional so-called mechanical height adjustment is not necessary.

Effects of the invention According to the invention explained above, the magnetic head 14
Since it is attached to the head mounting plate 6 with accurate angle division in advance, there is no need for any subsequent so-called angle adjustment, and by using the bimorph element 13, so-called mechanical height adjustment is also possible. This is completely unnecessary, and tracking can be easily performed using signals from the control circuit. Furthermore, since the head mounting plate 6 is imparted with elasticity in the radial direction, contact with the magnetic tape is improved, and high frequency signals can also be recorded and reproduced favorably.

Furthermore, when the head mounting plate 6 according to the present invention is manufactured by etching as described above, it is relatively easy to manufacture, and together with the elimination of head adjustment, it has the advantage of being suitable for mass production. be.

Incidentally, the rotating magnetic head device according to the present invention is
In addition to VTR, it can also be used for recording and playing PCM.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a magnetic head device according to the present invention, FIG. 2 is a plan view showing an example of a head mounting plate that can be used in the present invention, and FIG. 3 is an A of FIG.
- It is a sectional view on the A line. 6 is a head mounting plate, 10 is a notch, 11 is a bridge, 13 is an electro-mechanical conversion element, and 14 is a magnetic head.

Claims (1)

[Scope of utility model registration request] A head mounting plate made of a material that can be used as a spring material is provided with a plurality of notches to form at least two bridges extending in a direction perpendicular to a straight line passing through the center of rotation of the head mounting plate; A rotating magnetic head device comprising an electro-mechanical transducer mounted on the bridge and a magnetic head mounted at the tip of the electro-mechanical transducer.