JPS63225912A - Rotary magnetic head device - Google Patents

Abstract

PURPOSE:To easily obtain the optimum torsional resonance frequency, by deviating the end ring of a rotary magnetic head device from the center of the hole of a locking screw in an axial direction, and forming both end faces in the same shape. CONSTITUTION:The upper and lower end faces of the end ring 9 in the rotary magnetic head device are formed in the same shape, and the hole of the locking screw 10 of the end ring 9 is provided by deviating from the center in the axial direction, and the torsional resonance frequency can be varied by deviating the position of the locking screw 10 of the end ring 9 fixing a flywheel 11 on a shaft 3 by varying the mounting direction of the end ring 9, and varying the torsion length of the rotary shaft 3. In the rotary magnetic head device, the optimum torsional resonance frequency can be obtained by varying the torsion length of the shaft by varying the assembling direction of the end ring 9 mounting a flywheel 7 without changing the shape of a component and the number of components.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotating magnetic head device for a magnetic recording device.

[Conventional technology]

FIG. 3 is a sectional view showing a conventional rotating magnetic head device, in which (1) is a rotating upper drum, (2) is a rotating upper drum;
is a lower drum that is fixedly supported and does not rotate, (3) is a rotating shaft, and (4) is a 7-lunge that is press-fitted and fixed to the rotating shaft (3).
) is firmly supported. (5) is the lower drum (2)
a bearing (6) rotatably supporting the rotating shaft (3);
) is a stator fixedly supported on the lower side of the lower drum (2), σ) is a flywheel that also serves as the rotor of the rotary drive motor, (8) is a magnetic head attached to the upper drum (1), and (9) is a Rotate the flywheel (7) to the rotating shaft (3)
The end ring (10) attached to the end ring (9
) is a set screw that fixes the rotary shaft (3), and (11) is a screw that fixes the end ring (9) to the flywheel (7).

Next, the operation will be explained. In the rotating magnetic head device, when the flywheel (7), which also serves as a rotary drive motor, is rotated by an electric signal, the rotational force is applied to the screw (ll), the end ring (9), the set screw (lO), and the rotation. Axis (3 n,
7 lunge (4) and then to the upper drum (1) to rotate the magnetic head [F]) to obtain recording and reproduction signals.

[Problem that the invention seeks to solve]

Conventional rotating magnetic head devices are constructed as described above, so if there are variations in machining accuracy or the number of magnetic heads, the torsional resonance frequency of the shaft (3) will shift, causing problems.
In order to set the torsion resonance frequency to the optimum value, change the shape of either the upper drum (1) or the flywheel (7) to change the moment of inertia (%) and set the torsion resonance frequency to the optimum value. It's not easy because you have to do it.

This invention was made in order to solve the above-mentioned problems.In a rotating magnetic head device having an inappropriate torsional resonance frequency, it is possible to improve the number of parts without changing the shape and number of all parts. The object of the present invention is to obtain a rotating magnetic head device that can change the optimum resonant wave number by simply changing the assembly direction.

[Means for solving problems]

The rotating magnetic head device according to the present invention has an end ring (
9) have the same shape, and the hole for the set screw (1o) of the end ring (9) is offset from the center in the axial direction.By changing the mounting direction of the end ring (9), the shaft (3 N wears 7 Laihoi/k(11)
Set screw (lO) of the end ring (9) that secures the
The twisting length of the rotating shaft (3) is changed by shifting the position of the rotating shaft (3), thereby changing the torsional resonance frequency.

[Effect]

In the rotary magnetic head device according to the second aspect of the present invention, the torsional resonance frequency of the shaft can be adjusted without changing the shape of the parts or the number of parts.
9) By changing the assembly direction, the twisted length of the shaft is changed to obtain the optimum torsional resonance frequency.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In Figure 1, 3 (υ is the upper drum fixedly attached to the 7 langes (4), (2) is the lower drum that supports the bearing (5), (3) is the rotating shaft, and (4) is the rotating 7 langes press-fitted into the shaft (3), (5) is the bearing, (6) is the stator,
(7) is a flywheel that also serves as the rotor of the rotary drive motor, (8) is a magnetic head attached to the upper drum (υ), and (9) is an end ring.

Both end faces of the end ring (9) have the same shape, and the position of the hole for the set screw (10) is offset from the center in the axial direction. (10) rotates the end ring (9) to the rotation axis Q(3)1ζ
The fixing screw (11) is a screw that fixes the flywheel (7) to the end ring (9).

The torsional resonance frequency 7 of the shaft (3) of the rotating magnetic head device varies roughly as follows. What is the moment of inertia of the upper drum (1), the moment of inertia of the J1s flywheel ('7) -72, the twisted length of the shaft (3), and the proportional constants X and T? =1/2×f%×[toX(, TI+
, T2 ))/(LX(, TI+, r2)). As can be seen from the above equation, in order to change the torsional resonance frequency, it is sufficient to change the moment of inertia of the upper drum wheel or change the twisted length of the rotating shaft (3).

The rotating magnetic head device of the present invention includes an end ring (9)
Both end faces of the end ring (9) are made to have the same shape, and the set screw hole of the end ring (9) is offset from the center in the axial direction. Therefore, in order to change the torsional resonance frequency of the shaft (3), By changing the mounting direction of the ring, the shaft (
3) Change the torsional resonance frequency by changing the position of the set screw of the end ring that fixes the flywheel (7) and changing the twisted length of the shaft (3).

〔Effect of the invention〕

As described above, according to the present invention, the end ring (9) of the rotating magnetic head device has the hole for the set screw (1o) shifted from the center in the axial direction, and both end faces of the end ring (9) are formed in the same shape. Because of this, it is possible to change the resonant station wave number without changing the part shape or the number of parts, and without unnecessary machining.
Since this can be done simply by reversing the end ring (9) without adding any additional moisture, it is possible to obtain a rotating magnetic head device that is inexpensive and can change the torsional resonance frequency at any time.

[Brief explanation of drawings]

FIG. 1 is a T cross-sectional view of a rotating magnetic head device according to an embodiment of the present invention, and FIG. 2 is a diagram showing the torsional resonance wave number of the rotating shaft of the present invention changed. FIG. 3 is a diagram T0 showing a conventional rotating magnetic head device, in which (1) is an upper drum, (2) is a lower drum, (
3) is the rotating shaft, (4) is the 7 lange, (5) is the bearing, (6
) is the stator, (7) is the flywheel, (8) is the magnetic head, (9) is the end ring, (10) is the set screw, (
11) is a screw. In addition, in the figures, the same reference numerals indicate the same or corresponding parts T0 Agent Patent Attorney Masuo Oiwa Figure 1 Figure t42
.

Claims (3)

[Claims] (1) A rotating magnetic head device used in a magnetic recording/reproducing device, in which the torsional resonance frequency of a rotating shaft can be easily changed. (2) The rotating magnetic head device according to claim 1, wherein the torsional resonance frequency of the rotating shaft can be easily changed by changing the twisting length of the rotating shaft. (3) Both upper and lower end surfaces of the end ring that attaches the flywheel, which also serves as the rotor of the rotary drive motor for rotationally driving the rotating upper drum, to the rotating shaft have the same shape, and this end ring is fixed to the rotating shaft. Claims in which the end ring is provided with a hole for a mounting screw shifted from the center in the axial direction, and by changing the mounting direction of the end ring, the twisting length of the rotating shaft can be changed. 3. The rotating magnetic head device according to claim 2.