JP2624052B2 - Rotary drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary drive for rotating a magnetic disk having a rigid center hub at the center.

[0002]

2. Description of the Related Art As shown in FIG. 5, a conventional magnetic disk for recording and reproducing information magnetically includes a magnetic disk 4 for performing magnetic recording and a center hub 3 for rotating the magnetic disk 4. The center hub 3 has a main shaft insertion hole 3b and a substantially rectangular positioning hole 3a. A conventional magnetic disk rotation driving device for rotating and driving such a magnetic disk has a main shaft 5 inserted into a main shaft insertion hole 3b of a center hub 3 provided at the center of a magnetic disk 4, and fixed to the main shaft 5. A spindle hub 8 and a drive pin 6 elastically supported by a leaf spring 7 are provided. As shown in the plan view of FIG. 5 (a), the leaf spring 7 supporting the drive pin 6 is formed by forming a U-shaped hole 7a in a rectangular thin metal plate. It can bend in the direction.

[0006] When the magnetic disk 4 is inserted into the rotary drive and the center hub 3 is pressed against the spindle hub 8, the positioning of the center hub 3 is performed as shown in FIGS. When the drive pin 6 is not inserted into the hole 3a, the drive pin 6 pushes down the leaf spring 7 even if it contacts the back surface of the center hub 3, and the center hub 3 and the spindle hub 8 rotate relatively. Tolerate.

Next, when the main shaft 5 and the spindle hub 8 start rotating, the load on the magnetic disk 4 causes
The spindle hub 8 of the main shaft 5 rotates relatively to the center hub 3, and as shown in FIGS.
When the positioning holes 3a of the center hub 3 match,
The drive pin 6 is pushed upward by the restoring force of the leaf spring 7 and inserted into the positioning hole 3a. When the rotation continues, as shown in FIG.
The center hub 3 and the disc 4 rotate at the same speed as the main shaft 5 thereafter.

At this time, the drive pin 6 is pressed radially outward by the leaf spring 7 so that the center of the main shaft 5 and the center of the magnetic disk 4 are always coaxial.

In such a conventional rotary drive device, the drive pin 6 is supported by a single leaf spring 7 and elasticity in the radial and axial directions is given to the drive pin 6.

[0007]

When the drive pin 6 is supported by a leaf spring 7 having a U-shaped hole 7a, the leaf spring 7
When the magnetic disk is mounted, the amount of displacement of the drive pin 6 is affected by the accuracy of the mounting position of the drive pin 6 with respect to the magnetic disk, the variation in the elasticity of the leaf spring 7, and the accuracy of the mounting position of the leaf spring 7 with respect to the spindle hub 8. In other words, there is a problem that the force for pushing and expanding the main shaft 5 is not constant and varies. Further, since the support member of the drive pin 6 also serves as a spring, the degree of freedom in the shape of the spring is poor. To obtain appropriate spring elasticity, a certain size of dimension is required, and miniaturization is required. It was difficult.

Further, the axis of the drive pin 6 must always be parallel to the axis of the main shaft 5, but due to fluctuations in the load torque of the magnetic disk 4 and a decrease in the elasticity of the spring due to aging of the spring, the magnetic disk 4 does not move. When the disk is mounted and rotated, the axis of the roller 6 may be inclined, and the position of the magnetic disk 4 in the circumferential direction may fluctuate during rotation.

Since the timing of writing and reading on the magnetic disk 4 is based on the driving pin 6, if the driving pin 6 is inclined and its position in the circumferential direction fluctuates, the timing is shifted and recording / reproduction becomes impossible. There was a problem.

[0010]

Accordingly, the present invention has been conceived in order to solve such a problem. A main shaft insertion hole is formed at a center portion, and the main shaft insertion hole is formed in a radial direction from the main shaft insertion hole. A rotary drive having a main spindle inserted into the main spindle insertion hole and a position regulating member engaged with the positioning hole for rotationally driving a magnetic disk having a center hub having a positioning hole formed at a separated position. In the device, a lever member having a rotation fulcrum at a position eccentric in the radial direction from the main shaft and supporting the position restricting member at a position distant from the rotation fulcrum; A spring for providing elasticity and pressing the position restricting member against the back surface of the center hub, the position restricting member being engaged with the positioning hole, and rotating the magnetic disk to prevent the position. The position regulating member is configured to engage with the deepest position in the direction connecting the position regulating member and the pivot point to regulate the position of the center hub with respect to the main shaft. I do.

[0011]

As a support for the position restricting member, a lever member having rigidity that is rotatable about a pivot point is used to prevent the position restricting member from tilting, and to apply elastic force in a radially outward direction to the lever member and restrict the position. A spring that gives elasticity to press the member against the back of the center hub is provided separately from the lever member,
By making both the lever member and the spring independent,
The size of the lever member and the setting of the spring elasticity become free,
It is easy to cope with downsizing of the device.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS. 1 and 2, a spindle hub 8 fixed to a spindle 5 and a pin 9 provided at a position radially eccentric from the spindle 5 of the spindle hub 8 are shown.
And a lever 1 that rotates with the pin 9 as a rotation fulcrum and is difficult to expand and contract. The lever 1 supports a drive pin 6 at a position separated from the rotation fulcrum 9.

If the gap existing between the head 9a of the pin 9 and the back surface of the spindle hub 8 is set to be larger than the thickness of the plate-like lever 1, the lever 1
, And can rotate about the pin 9 as an axis.

A wire spring 2 having one end engaged with the lever 1 and the other end fixed to the spindle hub 8 is provided. It is configured to provide outward elasticity.

Next, the operation of the embodiment of the present invention will be described in comparison with the operation of the conventional apparatus shown in FIG.

When the driving pin 6 is not inserted into the positioning hole 3a of the center hub 3, as shown in FIG.
A resilient force is applied to the drive pin 6 to push it upward by the wire spring 2.

When the main shaft 5 rotates and the spindle hub 8 rotates with respect to the stationary center hub 3, and when the drive pin 6 reaches a position where it can be inserted into the positioning hole 3 a, the elastic force of the wire spring 2 causes it. When the drive pin 6 is pushed upward and inserted into the positioning hole 3a and continues to rotate, the drive pin 6 moves along the outside of the inner peripheral surface of the positioning hole 3a, and as shown in FIG. It engages with the deepest position of the positioning hole 3a in the direction connecting the pin 6 and the pin 9, and thereafter,
The magnetic disk 4 attached to the center hub 3 rotates at the same speed as the main shaft 5.

At this time, the drive pin 6 is connected to the center hub 3
When the wire spring 2 is rotated, it receives a reaction to generate a force for expanding and expanding in a radially outward direction, and furthermore, the elastic force of the linear spring 2 generates a force for expanding and expanding in a radially outward direction.
By changing the structure and dimensions of the spring 1, the spring characteristics can be freely set without affecting other members such as the lever 1.

Further, since the lever 1 is rotatable around the pivot 9 and has relatively high rigidity, the lever 1 is engaged in a state as shown in FIG. When combined, the lever 1 does not expand and contract and the drive pin 6 does not tilt, so that the center hub 3 of the magnetic disk 4 is accurately positioned with respect to the main shaft 5, and even if there is a change in load torque or a secular change of the spring, the magnetic force is reduced. An error does not occur in the set angle between the disk 4 and the main shaft 5, and the reliability of signal recording / reproduction is significantly improved.

When the driving pin 6 is engaged and rotated as shown in FIG. 6F, an outward component is generated by the reaction of the load torque without the wire spring 2, so that The position of the center hub 3 is accurately regulated with respect to the main shaft 5.

Therefore, the wire spring 2 that urges the lever 1 in the radially outward direction is only required to generate a force such that the drive pin 6 simply contacts the outside of the inner peripheral surface of the positioning hole 3a of the center hub 3. This is sufficient and does not necessarily require a large force for positioning the center hub 3.

(Other Embodiments) A compression spring as shown in FIG. 4 is mounted as the spring 2 for applying an elastic force in a radially outward direction while pressing the drive pin 6 supported by the lever 1 against the back surface of the center hub 3. This makes it easier to manufacture a spring having desired characteristics.

Positioning holes for drive pin 6 and center hub 3
If it is desired to reduce the sliding resistance with respect to the inner circumference of 3a, a rotating roller may be used for the drive pin.

[0024]

As described above, according to the rotary drive device of the present invention, the lever 1 for supporting the drive pin 6 and the spring 2 for biasing the lever 1 are formed separately. Therefore, the accuracy required for each member is reduced, and
Since the elasticity of the spring can be freely set, the size can be easily reduced without lowering the positioning accuracy of the magnetic disk.

The lever 1 for supporting the drive pin 6 is a rigid body and can rotate with the pin 9 as a fulcrum, so that the drive pin 6 tilts even if there is a change in load torque or aging of the spring. As a result, a stable rotation operation can be obtained in which the circumferential position of the magnetic disk 4 fluctuates during rotation and there is no time lag between recording and reproduction.

Further, since a substantially large positioning force does not act until the magnetic disk is positioned at the proper position, friction between the drive pin and the inner peripheral surface of the positioning hole 3a before the drive pin reaches the proper position. It is also possible to avoid a situation in which the positioning is stopped halfway by the force and the positioning cannot be performed accurately.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of a rotary drive device of the present invention;
(a) is a plan view and (b) is a longitudinal sectional view.

FIG. 2 is a perspective view of a main part of the device shown in FIG.

FIG. 3 is a longitudinal sectional view illustrating an operation state.

FIG. 4 is a longitudinal sectional view showing another embodiment.

5A and 5B are views showing an example of a conventional rotary drive device, wherein FIG. 5A is a plan view and FIG. 5B is a longitudinal sectional view.

6 (a) to 6 (c) are longitudinal sectional views, and FIGS. 6 (d) to 6 (f) are plan views, explaining the operation of the conventional apparatus shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Lever 2 ... Spring 3 ... Center hub 3a ... Positioning hole 3b ... Spindle insertion hole 4 ... Disc 5 ... Spindle 6 ... Drive pin 7 ... Support spring 8 ... Spindle hub 9 ... Pin (rotation fulcrum)

Claims (1)

(57) [Claims] A spindle insertion hole is formed at a center portion, and said spindle insertion hole is provided for rotating a magnetic disk having a center hub having a positioning hole formed at a position radially separated from said spindle insertion hole. A rotary drive device comprising: a main shaft inserted into a hole; and a position regulating member engaged with the positioning hole. The rotary drive device has a rotation fulcrum at a position radially eccentric from the main shaft, and is separated from the rotation fulcrum. A rigid member supporting the position restricting member at a position, and a spring for applying elasticity in a radially outward direction to the lever member and for applying elasticity for pressing the position restricting member against the back surface of the center hub; A regulating member is engaged with the positioning hole,
When the magnetic disk rotates and receives a reaction, the position regulating member engages with the deepest position in the direction connecting the position regulating member and the rotation fulcrum, and the center hub is attached to the main shaft. A rotary drive device for regulating the position of the rotary drive.