JPS5922270A - Restoring mechanism of reference position - Google Patents

Abstract

PURPOSE:To obtain an unexpensive reference position restoring mechanism with a simple structure, by using a spiral spring and a holder and adjusting the strength of the turning torque optionally. CONSTITUTION:A moving part 6 to which a magnetic head is fitted positions around a rotational shaft 7 through a bearing 8. The moving part 6 is fixed by a check plate 4 at the holder 3. The end part of the external periphery of the spiral spring 1 is fixed on the locking part 2 of the rotational shaft 7. The locking part 2 is fixed on the rotational shaft 7 at the cut part so as not to move around the rotational shaft 7. The holder 3 has plural projection parts 3' and at the position where required rotational torque is obtained by turning the holder 3 around the rotational shaft 7, the holder is fixed by the check plate 4 having holes to be fitted to the projection parts 3'. Thus, the previous setting of the rotational torque enables the moving part 6 to restore the reference position even if the rotation of the magnetic disc is stopped because of the failure of a controlling device or the magnetic disc collides with a hard stopper due to runaway.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a reference position return mechanism. Particularly, the present invention relates to a reference position rN and a return mechanism used in a positioning mechanism for rotating a magnetic disk drive, such as a tract mechanism.

In general, a voice coil motor system is used to position magnetic disks in a magnetic disk drive.
This is done by passing an electric current through the circuit.

On the contrary, in these magnetic disk devices, t''1,
The rotation of the magnetic disk may stop due to the magnetic head position (when determining 1 to 1), the rotation of the magnetic disk may stop due to abnormalities such as control device failure, stoppage, etc., and data may be written in droplets. The magnetic head is left behind on the magnetic disk that has been removed, and the magnetic disk and the magnetic head adhere to each other, damaging the data surface or making it impossible to perform the next positioning or determining operation.

Normally, magnetic disc devices have a mechanism that allows the magnetic head to always return to a certain reference position when the above-mentioned abnormality occurs, and information on that position is detected. Only then does the next positioning operation begin.

A conventional reference position return mechanism uses a condenser method. In other words, a charge is stored in a capacitor, and when an abnormality occurs, this charge is sent to the voice coil, and the resulting force returns the magnetic head to a certain reference position.Then, a magnet or the like is used to drive the magnetic head. holds the department.

However, with such a reference position return mechanism, if the drive part's moment of inertia (moment of inertia) and operating distance are long, the capacity of the capacitor becomes large, and since it always stores the same electric charge, it may become abnormal. The acceleration that acts on the drive unit at the time of occurrence is constant regardless of the operating distance, so the longer the operating distance, the faster the drive unit will be, and when the drive unit collides with the stopper to prevent runaway, it will bounce back and It goes back to.

As a result, the design of the hard stopper becomes complicated and the design becomes T7, which requires extra mounting space.

That is, the conventional reference position return mechanism t''1 has the drawbacks of being complicated in structure and expensive.

SUMMARY OF THE INVENTION An object of the present invention is to provide an entire reference position return mechanism that is simple in structure and inexpensive.

That is, an object of the present invention is to return a rotary drive part having a magnetic head to a reference position using a simple and inexpensive machine and tools, and to return it to a reference position. ff: An object of the present invention is to provide a reference position return mechanism capable of holding K.

Reference position return mechanism d1 of the present invention, Δ that achieves the above object
For this purpose, a spring-like spring is used, and the amount of rotational torque can be freely adjusted.

The reference position return mechanism of the present invention includes a retainer that has a plurality of protrusions and is rotatably attached to a rotating shaft, and a retainer that is attached to a movable part and that engages with any one of the protrusions. It is constructed to include a stop plate for locking the retainer, and a spiral spring having one end attached to the retainer and the other end attached to the locking portion of the rotating shaft.

That is, the reference position return mechanism of the present invention uses a spiral spring as the reference position return mechanism for a drive unit having a magnetic head, and is configured so that the magnitude of its rotational torque can be freely adjusted.

Next, embodiments of the present invention will be described with reference to the drawings.

FIGS. 1A and 1B are a plan view and a front partial sectional view showing an embodiment of the present invention.

In the reference position return mechanism shown in Figure 1 (al, (bl), the magnetic head (not shown) is
The moving part 6t is positioned around the rotating shaft 7 via the bearing 8. This movable part 6 has a spiral spring 1
A holder 3 for holding the is fixed by a stop plate 4. The outer peripheral end V of the spiral spring 1, the retainer 3
(not shown), and the other end of the inner circumference is fixed to a locking part 2 of the rotating shaft 7, and this locking part 2 is fixed to the rotating shaft 7. Rotating shaft 7 so that it does not move
Completely renovated and installed.

The cage 3 has a plurality of protrusions 3', and when adjusting the magnitude of one rotation torque, rotate the cage 3 about the rotating shaft 7, and at the position where the required torque is reached, Projection 3
Fix it with a stopper plate 4 with a hole that matches '.

In this way, you can set the rotation torque in advance,
Even if the magnetic disk stops rotating due to an abnormality in the control device or runs out of control and hits a hard stopper and bounces off, the movable part 6 containing the magnetic head must return to the reference position.

By changing the glue, the wire diameter and the number of turns of the spiral spring 1, the magnitude of the torque and the difference between them can be freely set with respect to the rotation angle.

'Also, compared to coil springs, the required torque is
The stress applied to the wire is very small, so it has a long life.
Considering the shape of the mainspring, the mounting space is small.

FIG. 2 is a front view showing an example of the use of the embodiment shown in FIG.

That is, as shown in FIG.
r, arm assembly 11 installed vertically and equipped with a magnetic head;
If there is a weight imbalance with respect to the reference position return mechanism 12 shown in detail in Figure 1 (81, BL), an off-senohl may occur in the positioning of the magnetic head due to an external excitation force (for example, an earthquake). However, if the rotational torque of the weight-unbalanced shellfish is applied in advance by a spiral spring that generates rotational moment) Ml , M2'<
The arm assembly 11 can be normally positioned around the outer periphery of the magnetic disk 9.

Fig. 2 describes the case where the reference position return mechanism shown in Fig. 1 (ta), (131) is mounted vertically, but by mounting it horizontally and setting the reference position on the inner or outer periphery of the magnetic disk. It can also be used to automatically return to the reference position using the restoring force of a spiral spring.

The reference position return mechanism of the present invention uses a spiral spring and a retainer to freely adjust the magnitude of rotational torque, so it has the advantage of being simple in structure and inexpensive.

That is, the reference position return mechanism of the present invention has the advantage that by using a mainspring in the positioning mechanism section of a magnetic disk drive, it is possible to obtain a reference position return mechanism that is inexpensive, has a long life, and requires a small mounting space. be.

[Brief explanation of drawings]

Figures (R1 and (bl) are a plan view and a front partial sectional view showing an embodiment of the present invention, and Figure 2 is a front view for explaining an example of use of the embodiment shown in Figure 1. 1... Spring-like spring, 2... Locking part, 3... Retainer, 3'... Protrusion, 4
...Stopping plate, 5...Set screw, 6.
...Movable part, 7...Rotation Ql+, 8...
...)" IJ song 9...magnetic disk, 10...magnetic disk device, 11...
・Arm assembly, 12...Reference position return mechanism,
Ml, R2...Rotating moment. Kaya 1 figure R7 Kaya Z times

Claims (1)

[Claims] A retainer having a plurality of protrusions and rotatably attached to a rotating shaft;
a stop plate for engaging with and locking the retainer, and a spiral spring having one end engaged with the retainer and the other end engaged with a retaining portion of the rotating shaft. koto'fc
Reference position return mechanism with ltYi4a.