JPS62208462A - Driving system for spindle motor in non-sandwiching type floppy disk driving device - Google Patents

Abstract

PURPOSE:To improve a writing track density by interrupting a driving electric current or a voltage at least one time at the time of starting and stopping and coasting a spindle motor. CONSTITUTION:When a starting command (a) is inputted from a system device 11 to a time control IC13, the time control IC13 outputs a rotating command signal (b) to a motor control IC14, a spindle motor 8, from when it is started, is topped and coasted for a constant time after a constant time or after 2-3 rotations and next, shifted to a stationary rotation. Consequently, the unfair chucking of the floppy disk is corrected, the chucking performance is widely improved and the problem of an error due to the unfair chucking, which comes to be the problem for the driving device of a micro-floppy at present, can be cancelled.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a spindle motor drive system in a non-clamping floppy disk drive device (hereinafter referred to as an FDD device) in which a floppy disk is driven by a drive pin. It is related to.

[Prior art and its problems]

Traditionally, 5.25' and 8' floppy disks (hereinafter referred to as FDs) have been the mainstream magnetic recording media, but as office automation equipment has become smaller, 3 and 5' floppy disks called micro floppies have become mainstream. The demand for FD is increasing.

Since this 3.5' FD is small, it is similar to the conventional 5.25' FD.
Instead of using the spindle hub and collet sandwich method like the ', 8' FD, it is placed in a hard cassette case.
As shown in FIGS. 1 and 2, the FDD device employs a system in which a drive pin 4 provided in a spindle hub 7 is engaged with a drive hole 3 provided in an FDI to drive the device.

In the figure, 2 is a hub metal fitting provided with a drive hole 3 and a center hole 6, 5 is a spindle shaft driven by a spindle motor 8, and the spindle hub 7 is connected to this spindle shaft 5.

In the illustrated example, the drive pin 4 is fixed to one side of the ring-shaped spring piece 9 with adhesive so that the drive pin 4 can be easily engaged with the drive hole 3, and the other side of the ring-shaped spring piece 9 is fixed with adhesive. It is fixed to the spindle hub 7 with screws 10.

However, this non-pinching type FD driven by drive pin 4
The drive system of the D device does not have the hub metal fitting 2 in close contact with the spindle hub 7 unlike the conventional clamp-type FDD device, and in addition, Since there is play between the center hole 5 and the center hole 6, there is a problem that the chucking is not constant, and the writing/writing may not be performed stably.

SUMMARY OF THE INVENTION Therefore, the present invention provides a spindle motor drive system that allows each FD to be chucked in a constant state depending on its manufacturing state even if the manufacturing accuracy of the FDs varies.

[Means for solving problems]

The present invention has been made to solve the above problems, and is designed to stop or coast the spindle motor by cutting off the drive current or voltage at least once during startup.

[For production]

If such a drive method is adopted, incorrect chucking is corrected by forcibly moving the FD in the rotational direction relative to the drive unit when the spindle motor is temporarily stopped or coasting, and the spindle motor is restarted. By rotating, chucking is always performed in a constant positional relationship.

Therefore, according to this method, read/write errors can be reduced and write trunk density can be improved.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 3 shows a spindle motor drive circuit according to an embodiment of the present invention. When a start command a as shown in FIG. 4 Outputs a rotation command signal as shown in Figure 4, and controls the spindle motor 8.
After a certain period of time or two or three revolutions after starting, the motor stops or coasts, and then shifts to steady rotation.

In addition, although the above-mentioned embodiment showed the principle circuit by hardware, in the case of practical use, it can also be incorporated into control software so that similar control is performed.

〔Effect of the invention〕

By controlling the rotation and stopping of the spindle motor 8 or coasting one rotation, incorrect chucking of the FD can be corrected, and the chucking performance can be greatly improved.
The problem of errors caused by incorrect chucking, which is currently a problem with the D device, will be resolved.

[Brief explanation of drawings]

Fig. 1 is a plan view showing the relationship between the FD and the drive pin in a known FDD device, Fig. 2 is a partially cutaway side view of the same, and Fig. 3
The figure is a process diagram of an embodiment of the present invention, and FIG. 4 is a time chart of a start signal and a rotation command signal. 8...Spindle motor 11...System device 12...Spindle motor control device 13...Time control IC 14...Motor control IC Fig. 1 Fig. 2 Fig. 6 Fig. 4 Fig. α 8...・Spindle morph 11...System device 12...Spindle motor control device 13...Time control IC 14...Motor control IC

Claims (1)

[Claims] A method for driving a spindle motor in a non-clamping type floppy disk drive device, characterized in that the drive current or voltage is cut off at least once during startup to stop or coast the spindle motor.