JPH0578100B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for rotationally driving a disk used for magnetic recording or the like.

[Conventional technology]

6 to 9 are diagrams showing a conventional disk rotation drive device disclosed in, for example, Japanese Utility Model Application Publication No. 60-3950, in which FIG. 6 is a plan view and FIG.
Line sectional view, Figure 8 is a plan view with the rotating plate removed,
FIG. 9 is an enlarged cross-sectional view taken along the line - in FIG. 8.

In the figure, a recording medium 2 such as a disc-shaped magnetic disk is a rotary plate fixed at the center of the recording medium 1, and a square center hole 2a is provided in the center.
A nearly rectangular window hole 2 is located eccentrically with respect to a.
b is provided. 3 is a motor (not shown)
A pedestal 5 fixed to the rotating shaft 4 of the pedestal 3 is arranged on the back side of the pedestal 3, and one end of the pedestal 5 is pivoted to a pin 6 planted on the back side of the pedestal 3 so that it can rotate and be displaced in the axial direction. 7 is a driving pin consisting of a roller supported on the other end of the arm plate 5, and 8 is arranged on the back surface of the pedestal 3, one end of which is fixed to the pedestal 3, and the other end of which is fixed to the pedestal 3. It is an elastic body made of a wire spring that engages with and presses the other end of the arm plate 5.

A conventional disk rotation drive device is configured as described above, and the recording medium 1 is moved from the side,
The center hole 2a of the rotating plate 2 is fitted into the tip of the rotating shaft 4. At this time, the drive pin 7 is at position 7A in FIG.
, it is pushed down by the back surface of the rotary plate 2. Next, when the rotating shaft 4 starts rotating by the motor, the pedestal 3 also rotates, and the driving pin 7 slides on the back surface of the rotating plate 2, moving to a position 7 corresponding to the window hole 2b.
When it reaches B, it is pushed up by the restoring force of the elastic body 8 and inserted into the window hole 2b. When the pedestal 3 further rotates, the drive pin 7 rolls along the inner edge of the window hole 2b and comes to the end of the window hole 2b as shown in FIG.
Thereafter, the rotating plate 2 and the pedestal 3 rotate at a constant speed. At this time, the driving pin 7 is pressed against the inner edge of the window hole 2b by the elastic body 8, and applies a force to the rotary plate 2 in the radial direction. As a result, the rotating plate 2 relative to the rotating shaft 4,
That is, the recording medium 1 is positioned.

[Problem that the invention seeks to solve]

In the conventional disk rotation drive device as described above, the elastic body 8 always presses the arm plate 5, and the reaction force of the drive pin 7 is large, so the external force applied to the recording medium 1 becomes large, causing its fatigue. The problem is that it gets bigger.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a disk rotation drive device that can reduce external force applied to a recording medium and reduce its fatigue.

[Means for solving problems]

In the disk rotation drive device according to the present invention, an arm plate is provided on a suction plate made of a permanent magnet driven by a rotating shaft, and a drive pin protrudes through the suction plate on the arm plate and engages with a window hole in the rotary plate. An elastic body is provided on the back surface of the suction plate, and when the drive pin moves beyond a certain distance, it comes into contact with the arm plate and applies a force in the radial direction to the rotary plate.

[Effect]

In this invention, when the drive pin is pushed down by the rotary plate, the elastic body does not act, so
The pressing force is small. When the suction plate rotates and the drive pin contacts the inner edge of the window hole, the elastic body and the arm plate come into contact and apply force to the rotary plate.

〔Example〕

Figures 1 to 6 are views showing one embodiment of the present invention, where Figure 1 is a plan view with the rotating plate removed, Figure 2 is a sectional view taken along the line - - of Figure 1, and Figure 3 is a front view. , 4th
The figure is a back view, FIG. 5 is an explanatory diagram of the operation, and FIG. 6 is a diagram similar to the conventional device.

Note that the same parts as in the conventional device are indicated by the same reference numerals.

In the figure, reference numeral 11 denotes an adsorption plate made of a disc-shaped permanent magnet fixed to the pedestal 3. A space 11a is provided near the periphery to pass through, and one end of the arm plate 5 is attached to a pin 6 erected on the back surface. is pivotally supported so that it can rotate and be displaced in the axial direction. A drive pin 7 supported at the other end of the arm plate 5 projects from the cavity 11a. Further, two support shafts 12 are provided on the back surface of the suction plate 11, and an elastic body 8 made of a wire spring is hooked onto these.
As shown in FIG.
A gap A is created by contact with the inner edge of 1a.

In the disk rotation drive device configured as described above, when the rotating plate 2 is not present,
The arm plate 5 is attracted to the suction plate 11, and there is a gap A between the arm plate 5 and the tip of the elastic body 8. Therefore, when the drive pin 7 is pushed down by the rotary plate 2 as shown by the chain line in FIG. 3, the elastic body 8 does not act, so the pushing down force may be small, which is desirable because the external force applied to the recording medium 1 is small. becomes. At this time, since no force in the radial direction is required yet, there is no friction due to this force in the radial direction, and the drive pin 7 is pushed down with a light force, reducing the possibility that it will not recover due to friction. When the suction plate 11 rotates and the drive pin 7 comes to a position corresponding to the window hole 2b, the arm plate 5 is attracted to the suction plate 11 and the drive pin 7 is inserted into the window hole 2b. Further, the suction plate 11 rotates, and the drive pin 7 moves into the window hole 2b.
When the arm plate 5 comes into contact with the inner edge of the
Similar to the conventional device, a centering force is applied to the centering force.

〔Effect of the invention〕

As explained above, in this invention, an arm plate is provided on a suction plate made of a permanent magnet driven by a rotating shaft, and the arm plate supports a drive pin that protrudes through the suction plate and engages with a window hole in the rotary plate. An elastic body is provided on the back of the adsorption plate, and when no external force is acting on the drive pin, the arm plate has a gap between it and the elastic body, and when the drive pin moves more than a certain distance, it contacts the elastic body and rotates. Since force is applied to the plate in the radial direction, the external force applied to the recording medium can be reduced, fatigue caused by it can be reduced, and the drive pin can be reliably returned to its normal position. be.

[Brief explanation of drawings]

1 to 5 are diagrams showing one embodiment of a disk rotation drive device according to the present invention, and FIG.
Figure 2 is a plan view with the rotating plate removed from the figure, Figure 2 is a sectional view taken along the - line in Figure 1, Figure 3 is a front view, and Figure 4 is a front view.
5 is an explanatory view of the operation of FIG. 4, FIG. 6 is a plan view showing the present invention and a conventional disk rotation drive device, and FIGS. 7 to 9 are conventional disk rotation Figure 7 is a cross-sectional view taken along the - line in Figure 6, Figure 8 is a plan view with the rotating plate removed from Figure 6, and Figure 9 is an enlarged cross-sectional view taken along the line - in Figure 8. be. In the figure, 1 is a recording medium, 2 is a rotating plate, 2a is a center hole, 2b is a window hole, 4 is a rotating shaft, 5 is an arm plate, 7 is a drive pin, 8 is an elastic body, and 11 is a suction plate. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] 1. A rotary plate fixed to a plate-shaped recording medium, having a central hole in the center into which the tip of a rotating shaft of an electric motor is loosely fitted, and a window hole located eccentrically with respect to the central hole, and this rotary plate. an adsorption plate made of a permanent magnet and fixed to the rotating shaft; an arm plate disposed on the back side of the adsorption plate and having one end pivoted to the adsorption plate so as to be movable in the axial direction; a drive pin that is supported by the other end of the arm plate and projects through the suction plate while the arm plate is attracted to the suction plate, engages with a window hole in the rotary plate, and moves toward the center of the rotary plate; , an elastic body provided on the back surface of the adsorption plate, which contacts the arm plate and applies a force in the radial direction to the rotary plate through the drive pin and the window hole when the drive pin moves beyond a certain distance; A disk rotation drive device equipped with.