JPH033160A - Index detector and disk rotating mechanism for data recording and reproducing device - Google Patents

Abstract

PURPOSE:To surely execute the read/write operation of data to a storage medium to always execute a rotary movement at a stationary rotating speed by outputting a sure INDEX signal when the spindle mechanism of a data recording and reproducing device reaches a stationary rotary condition. CONSTITUTION:A motor-on signal to activate a motor 13 is outputted from a control circuit FDMC 24 of a floppy disk device FDD 22, and the driving force of the motor 13 is transmitted through a belt 12 to a pulley 11 of the spindle mechanism. Thus, a slit plate 20 is rotatingly driven, and a slit 20a for a rotation control and a slit 20b for an index detection formed to a plate 20 are detected by a photosensor 21. The photosensor 21 outputs an FG signal according to the detection of the slit 20a, the pulley 11 of the spindle mechanism is gradually accelerated from a low speed, and it is made to reach a constant speed drive. At such a time, the FG signal is changed in a prescribed period, the fact that the period reaches a set value is decided by a pulse period deciding part 23, and the INDEX signal is outputted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to an index detection device and a disk rotation mechanism of a data recording/reproducing device such as a floppy disk device.

(Prior Art) Conventionally, for example, in a floppy disk device (FDD), there is a device that uses a belt-driven mechanism as a disc rotation mechanism for rotating a recording medium. As shown in FIG. 10, this type of mechanism has a belt attached to a pulley connected to a spindle shaft 10.
2 is hung, and the motor 1 is connected via this belt 12.
It is configured so that the driving force of No. 3 is transmitted. A spindle shaft 10 is supported by a bearing 14, and a chucking table 1 for chucking a recording medium 15 is provided.
It has B. As shown in FIG. 9, the belt 12 connects the pulley 17 of the motor 13 and the pulley 11 of the spindle mechanism, and transmits the driving force of the motor 13 to the pulley 11.

By the way, in an FDD, when the recording medium 15 is rotated by a spindle mechanism, it is necessary to perform rotation control and index detection. For this reason, in the belt drive system, as shown in Figure 3, the pulley 1 of the spindle mechanism
1 is provided with a slit plate 20, and an optical sensor 21 for detecting the slit of this slit plate 20 is provided. As shown in FIG. 4, the slit plate 20 has
A plurality of rotation control slits 20a and one index detection slit 20b are formed. Optical sensor 2
1, when the slit plate 20 rotates, as shown in FIG. 5, it outputs an FG multiplied signal which is a detection signal corresponding to the detection of the rotation control slit 20a and the index detection slit 20b. The FG multiplied signal from the optical sensor 21 is output to the FDMC, which is a control circuit of the FDD.

As shown in FIG. 5, the FDMC generates an index detection signal D corresponding to the FG multiplication signal index detection slit 20b based on the internal counter signal and the FG multiplication signal.
FD as an INDEX signal which is an interface signal
It will be output to C.

However, as shown in FIG. 6, when the motor-on signal for starting the motor 13 is output from the FDMC and the above-mentioned INDEX signal is generated, an erroneous pulse P, which is an erroneous INDEX signal, occurs. There are things to do. This is because when the motor 13 approaches constant-speed rotation drive, the index detection signal ID is not at the original index position due to variations in the reset time Ta of the internal counter signal and differences in the duty ratio of the FG signal. This is because it may be output.

On the other hand, in the belt drive system, as shown in FIG. 7, the pulley 11 and belt 12 are in contact and engaged, but in order to prevent slippage between the two, in other words, to obtain a stable rotational state. Therefore, it is necessary to increase the tension of the belt to some extent. However, if the belt tension is too strong, the bearing 14 in the spindle mechanism and the spindle shaft l
There is a problem that the friction between the spindle mechanism and the spindle mechanism becomes large and the life of the spindle mechanism is shortened. Furthermore, since the load during rotational driving increases, the current consumption of the motor 13 increases.

(Problems to be Solved by the Invention) In a conventional belt-driven FDD, an erroneous INDEX signal may be output near when the motor 13 reaches constant rotational speed. In FDD, two consecutive valid index intervals (160ms to 240ms) result in (
(See FIG. 6), since the READY signal is output to the FDC, there is an inconvenience that reading/writing is started before the recording medium 15 reaches a steady rotation state.

Also, the belt 12 is connected to the pulley 11 of the spindle mechanism.
It is difficult to adjust the tension. If the tension of the belt 12 is weak, slippage is likely to occur between the two; if it is too strong, the friction between the bearing 14 and the spindle shaft 10 increases.

An object of the present invention is to provide an index detection device for a data recording/reproducing device that can output a reliable INDEX signal when a spindle mechanism reaches a steady rotation state. Furthermore, it is an object of the present invention to provide data recording that can reliably prevent slippage between the pulley and belt in the spindle mechanism and provide a stable rotational state without increasing the tension of the belt that much. An object of the present invention is to provide a disk rotation mechanism for a playback device.

[Structure of the Invention] (Means and Effects for Solving the Problems) The present invention detects a detection target provided in the spindle mechanism when the spindle mechanism is rotationally driven, and outputs a rotation control detection pulse and an index detection pulse. and a control means for outputting an index detection pulse outputted from the sensor means as an index signal when the period of the detection pulse for rotation control outputted from the sensor means is within a preset tolerance range. This is an index detection device.

Further, in the belt drive system of the present invention, the pulley has a pulley whose surface that engages and contacts the belt member is made of a rubber member or a plastic member with a relatively large coefficient of friction, and the motor is transmitted through the belt member. This is a disk rotation mechanism equipped with a spindle mechanism that rotates a recording medium using a driving force.

(Example) The present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a floppy disk system according to a first embodiment.

As shown in FIG. 1, the FDD 22 of the same embodiment is provided with a control circuit (FDMC) 24 having a pulse period determining section 23. FDM C24 is the spindle mechanism and carriage mechanism 2 of FDD22 as shown in FIG.
5 drive control is executed, and various interface signals (STEP signal) are sent to the FDC2B.

INDEX, INDEX signal, DY signal, etc.) are exchanged.

The pulse period determination unit 23 is a key element of the embodiment, and determines whether the FG double signal period output from the optical sensor 21 is within a preset tolerance range, and determines whether or not it is within the tolerance range. In this case, the INDEXNDEX signal is output to C2B.

Next, the operation of this embodiment will be explained. First, the power is turned on and the motor 13 is transferred from the FDM C24 of the FDD22.
When a motor-on signal for starting the motor is output, the driving force of the motor 13 is transmitted to the pulley 11 of the spindle mechanism via the belt 12. As a result, as shown in FIG.
0a and the index detection slit 20b will be detected. The optical sensor 21 is a rotation control slit 2
In response to the detection of 0a, an FG multiplied signal as shown in FIG. 2 is output. Spindle machine (Nano pulley 11 is gradually accelerated from low speed to reach constant speed drive, so the period is Tb, Tc, Td, Te (T
b>Tc>Td>Te). When the period of the FC signal reaches Te within a preset allowable range, the pulse period determination unit 23 inputs an index signal according to the detection by the index detection slit 20b of the FC signal.
DEXNDEX signal Output to D026. This period Te is a period corresponding to constant speed driving of the pulley 11 of the spindle mechanism. The pulse period determining section 23 includes, for example, a gate circuit, and when the FG multiplied signal period reaches Te within a preset allowable range, it outputs an M signal, which is a gate control signal, and outputs an INDEXNDEX signal from the gate circuit.

When the INDEX signal is output for several pulses, the FDC24 determines that the spindle mechanism holding the recording medium has reached a constant speed drive state, and sends the REA to the FDC2B.
Outputs DY signal. Upon receiving the READY signal, the FDC2B activates the 5 for driving the carriage mechanism 25.
Output the TEP signal to the FDMC24. In response to this 5TEP signal, the stepping motor of the carriage mechanism 25 is driven, and the carriage mechanism 25 carrying the head 27 moves in the radial direction (arrow A) of the recording medium (see FIG. 3).

By determining the cycle of the FC signal from the optical sensor 21 in this way, the INDEXNDEX signal can be output when the spindle mechanism reaches a constant speed drive state. In other words, it is possible to reliably prevent a situation in which an erroneous pulse of the IN D'EX signal occurs before the spindle mechanism reaches the constant speed drive state.

FIG. 8 is a plan view of the second embodiment.

In the second embodiment, in a belt-driven spindle mechanism as shown in FIGS. 3 and 10, a rubber member 31 having a relatively large coefficient of friction is provided on the surface of a pulley 30 that engages with the belt 12. Or a plastic member is provided. That is, the belt 12 engages with the pulley 30 via the member 31 having a relatively large coefficient of friction, and transmits the rotational driving force of the pulley 17 of the motor 13 to the pulley 30.

With such a configuration, a stable rotational state can be obtained. That is, since the friction between the belt 12 and the pulley 30 increases, it is possible to prevent a situation where the belt 12 and the pulley 30 easily slip. In this case, since it is not necessary to make the tension of the belt 12 so strong, the bearing 14 and the spindle shaft 10
It is possible to prevent a situation where the friction between the spindle mechanism and the spindle mechanism becomes large and the life of the spindle mechanism is shortened. Further, since it is possible to prevent a situation in which the load during rotational driving becomes particularly large due to the tension of the belt 12, it is possible to prevent the current consumption of the motor 13 from increasing.

[Effects of the Invention] As described in detail above, according to the present invention, a reliable INDEX signal can be output when the spindle mechanism reaches a steady rotation state. Therefore, data write/write operations can be reliably performed on a recording medium that is always rotating at a steady rotational speed.

Furthermore, it is possible to reliably prevent slippage between the pulley and belt in the spindle mechanism without increasing the tension of the belt in the belt drive system, reducing the lifespan of the spindle mechanism or damaging the motor. Since an increase in current consumption can be prevented, a stable rotational state can be obtained.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the configuration of a floppy disk system according to a first embodiment of the present invention, Fig. 2 is a timing chart for explaining the operation of the same embodiment, and Fig. 3 is a conventional belt drive system. A conceptual diagram showing the configuration of an FDD,
FIG. 4 is a partial detailed view of FIG. 3, FIGS. 5 and 6 are timing charts for explaining the conventional system, and FIGS. 7, 9, and 10 are respectively conventional spindle mechanisms. FIG. 8 is a diagram showing the construction of a spindle mechanism according to a second embodiment of the present invention. 11, 30...Pulley, 12...Belt, 13...
- Motor, 15... Recording medium, 20... Slit plate, 21... Optical sensor, 23... Pulse period determination section. Figure 1 Figure 5 Figure 2 Figure 6

Claims (2)

[Claims] (1) A belt-driven data recording and reproducing device includes a spindle mechanism that holds and rotates a recording medium and has a detection target for rotation control and index detection, and detects the detection target when the spindle mechanism is rotationally driven. and a sensor means for outputting a rotation control detection pulse and an index detection pulse, and an output from the sensor means when the period of the rotation control detection pulse outputted from the sensor means is within a preset tolerance range. An index detecting device for a data recording/reproducing device, comprising: a control means for outputting the index detecting pulse as an index signal. (2) In a disk rotation mechanism of a belt-driven data recording and reproducing device, a motor is a rotational drive source for a recording medium, and a belt member engages with a pulley of this motor to transmit the driving force of the motor. and a pulley whose surface that engages and contacts the belt member is made of a rubber member or a plastic member with a relatively large coefficient of friction, and the recording medium is driven by the driving force of the motor transmitted through the belt member. 1. A disk rotation mechanism for a data recording/reproducing device, comprising: a spindle mechanism for rotationally moving the disk.