JPH10162525A - Disk unit - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To accurately calculate the number of tracks even on a disc whose track pitch is not a standard average value, and to shorten the processing time for accessing a target time address. A linear velocity measuring means shifts a track at a position of a time address of 0 seconds, and obtains a linear velocity measurement value by using a time address before and after the time and a track shift time. The track pitch measuring means 13 performs a track shift at a position of a certain time address, and a track pitch measured value 16 is obtained from the time addresses before and after the track shift and the track shift time. The calculating means 10 calculates the number of tracks between the current time address and the target time address from the obtained linear velocity and track pitch, and the access means 9 shifts the track by the track, thereby obtaining the target time address of the disk 1. To access.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk device used for reproducing and recording information on a disk in which information such as music and images is recorded on spiral tracks by digital signals.

[0002]

2. Description of the Related Art Generally, on a disk in which information such as music and images is recorded on a spiral track by a digital signal, a time address is recorded along the track. In order for the pickup that reads and writes data on the disk to access the position of the target time address from the time address of the current position, the number of tracks between the current time address and the target time address is calculated, and the number of tracks is calculated. By performing the track shift, the target time address of the disc can be accessed.

FIG. 6 is a block diagram showing the configuration of a conventional disk drive. 6, reference numeral 1 denotes a disk on which information is recorded on a spiral track by digital signals,
2 is a spindle motor for rotating the disk 1, 3 is a pickup for reading digital signals recorded on the disk 1, and 4 is a pickup driving device for changing the position of the pickup 3 for reading digital signals recorded on the disk 1. Numeral 5 denotes a signal processing device for converting a digital signal read from the disk 1 by the pickup 3 into information or a current time address.

Reference numeral 6 denotes a pickup driving device 4 and a spindle motor 2 for driving the pickup 3 and the disk 1 in the focus direction, the tracking direction, and the rotation direction.
A servo processing device for controlling the driving of the signal processing device;
A means for reading the current time address from the CPU, 8 means for shifting the set number of tracks to the servo processor 6, 11 means for measuring the linear velocity of the disk 1, 12
Is a means for measuring the track shift time, 14 is the radius value from the center of the disk 1 to the start time of the time address 0 second, 15 is the measured linear velocity of the disk 1, 61 is the average value of the track pitch standard of the disk 1, 10 is Is a means for calculating the number of tracks between the current time address and the target time address according to the access instruction, and 9 is a means for accessing the target time address.

An example of a method of calculating the number of tracks on the disk 1 by the number-of-tracks calculating means 10 will be described with reference to FIG.

Reference numeral 31 denotes a position of a time address 0 second of the disk 1, and an area A of a circle whose radius from the center of the disk 1 is r (mm) can be obtained by the following equation.

[0007]

(Equation 1)

Reference numeral 32 denotes a time address ta (s) of the disk 1.
At the position of ec), the area Aa of a circle whose radius from the center of the disk 1 is ra is obtained by the following equation.

[0009]

(Equation 2)

Reference numeral 33 denotes an area when the time address 0 (sec) to the time address ta (sec) are linear, so that the linear velocity is v (mm / sec) and the average value of the track pitch standard is d ₀ mm. Then, the area Aa from the equation (1) to the time address ta (sec) is obtained by the following equation.

[0011]

(Equation 3)

From equations (2) and (3), the radius ra (mm) from the center of the disk 1 to the time address ta (sec)
Is obtained by the following equation.

[0013]

(Equation 4)

The radius of the position of the current time address t1 (sec) is r1 (mm), and the target time address t2 (sec)
Assuming that the radius of the position c) is r2 (mm), the number of tracks DTN between the current time address and the target time address
Is obtained by the following equation.

[0015]

(Equation 5)

From equations (4) and (5), the current time address t
The number of tracks DTN between 1 (sec) and the target time address t2 (sec) is obtained by the following equation.

[0017]

(Equation 6)

An example of a method of calculating a measured value of the linear velocity by the linear velocity measuring means 11 will be described with reference to FIG.

Radius ra (mm) from the center of the disk 1
When one track shift 41 is performed near 45, the time address 42 before one track shift is set to ta1 (se).
c), the time address 43 after one track shift is set to ta2 (sec), and the track shift time 44 is set to ta.
Assuming that the time is 3 (sec), the time tla (sec) for one round near the radius ra (mm) is obtained by the following equation.

[0020]

(Equation 7)

Then, the radius value r from the center of the disk 1 is
(Mm) is known, and one track is shifted near 0 second, the time address before one track shift is set to ts1 (sec), and the time address after one track shift is set to ts2 (sec). Assuming that the shift time is ts3 (sec), the time tls (sec) for one round near the time address 0 (sec) is obtained from the equation (7).
It is obtained by the following equation.

[0022]

(Equation 8)

Let the linear velocity of the disk 1 be v (mm / sec)
Then, the circumference L of a circle whose radius from the center of the disk 1 is r (mm) is obtained by the following equation.

[0024]

(Equation 9)

From the equation (9), the linear velocity v (m
m / sec) is obtained by the following equation.

[0026]

(Equation 10)

Therefore, the measured value of the linear velocity can be obtained by the equations (8) and (10). Next, an access operation according to the conventional example will be described with reference to a flowchart shown in FIG.

The start of the disk 1 is started (step 2
0), focus / tracking /
The pull-in process of the pickup 3 is performed by the rotation servo process (step 21). Next, the track is shifted by one track near the time address 0 second by the linear velocity
Time address ts1 (sec) before this track shift
And the time address ts2 (se
c) and the track shift time ts3 (sec), the time ts (se) for one round near the time address 0 (sec).
c) is obtained by Expression (8), and the linear velocity measurement value 15 of the disk 1 is obtained from Expressions (8) and (10) and the radius value 14 at the time address 0 second (Step 22).

If there is an instruction to access the target time address (step 24), the track number calculating means 1
At 0, equation (6), current time address t1 (sec),
From the target time address t2 (sec), the linear velocity measurement value 15 of the disk 1, the track pitch standard average value 61 of the disk 1, and the radius value 14 of the time address 0 second, the number of tracks between the current and target time addresses (Step 71), and the track shift means 8 performs a track shift on the number of tracks calculated in step 71 (step 2).
6). It is checked whether the current time address after the track shift matches the target time address (step 2).
7) If they match, the access is terminated (step 2)
8) If the current time address is not equal to the target time address, the process returns to step 71 again to calculate the number of tracks, shift the track, and repeat until the current time address becomes equal to the target time address, thereby ending the access. .

As described above, in the above-described conventional disk device, the linear velocity is obtained by the linear velocity measuring process of the disk 1, and the number of tracks between the current time address and the target time address is obtained according to the linear velocity of the disk 1. Then, the target time address of the disk 1 can be accessed by performing the track shift by the number of tracks.

[0031]

However, in the above-mentioned conventional disk device, the track number calculating means 10 between the current time address and the target time address calculates using the track pitch standard average value 61. Therefore, the number of tracks cannot be accurately calculated on the disk 1 having a track pitch other than the standard average value, and there is a problem that it takes time to access the target time address.

The present invention solves such a conventional problem, and can accurately calculate the number of tracks even on a disk having a track pitch other than the standard average value, thereby shortening the processing time for accessing the target time address. It is an object of the present invention to provide a disk device capable of performing such operations.

[0033]

According to the present invention, to achieve the above object, the track is shifted at a position where the radius value from the center of the disk is known, and the disk linear velocity is calculated from the time addresses before and after the track shift. A linear velocity measuring means for measuring the disk speed and a track pitch measuring means for shifting the track at a position where the radius value from the center of the disk is unknown, and measuring the track pitch of the disk from the time addresses before and after the track shift, The number of tracks between the current time address and the target time address of the disc is obtained from the measured values of the linear velocity and the track pitch of the disc, the number of tracks is set from the calculated number of tracks, and the track is shifted to the target time address of the disc. It is configured to access.

As a result, it is possible to obtain a disk device in which the number of tracks can be accurately calculated and the processing time for accessing the target time address can be reduced.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, a current time address reading means for reading a time address of a current position of a disk based on a time address on the disk, and a set track number of the disk are shifted. A track shift means for performing a track shift at a position where a radius value from the center of the disc is known, and a linear velocity measuring means for measuring a linear velocity of the disc from time addresses before and after the track shift; Track pitch measuring means for shifting the track at a position where the radius value is unknown and measuring the track pitch of the disc from the time addresses before and after the track shift, and the current time address of the disc from the measured values of the linear velocity of the disc and the track pitch Track number calculating means for calculating the number of tracks between the target time address and An access means for setting the number of tracks from the calculated number of tracks and performing a track shift to access a target time address of the disk. Since the track pitch is determined by the measurement process, the number of tracks between the current time address of the disk and the target time address of the disk is calculated according to the linear velocity of the disk and the track pitch of the disk at the time of the access process to the target time address. It has the effect that it can be determined.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a disk device according to an embodiment of the present invention.

In FIG. 1, 1 is a disk on which information is recorded on a spiral track by a digital signal, 2 is a spindle motor for rotating the disk 1, 3 is a pickup for reading a digital signal recorded on the disk 1, 4 Is a pickup driving device for changing the position of the pickup 3 for reading a digital signal recorded on the disk 1. Reference numeral 5 denotes a signal processing device for converting a digital signal read from the disk 1 by the pickup 3 into information or a current time address. Reference numeral 6 denotes a pickup driving device for driving the pickup 3 and the disk 1 in a focusing direction, a tracking direction, and a rotating direction. 4 is a servo processor for controlling the driving of the spindle motor 2 and the spindle motor 2.

7 is a means for reading the current time address from the signal processing device 5, 8 is a means for shifting the set number of tracks to the servo processing device 6, 11 is a means for measuring the linear velocity of the disk 1, and 12 is a track. Means for measuring the shift time; 13 means for measuring the track pitch of the disc 1; 14 the radius value from the center of the disc 1 to the start position of the time address 0 second; 15 the measured linear velocity of the disc 1; Is a track pitch measurement value of the disk 1, 10 is means for calculating the number of tracks between the current time address and the target time address according to an access instruction, 9
Is a means for accessing the target time address.

An example of a method of calculating the number of tracks on the disk 1 by the number-of-tracks calculation processing means 10 will be described with reference to FIG.

Numeral 31 denotes a position of the disk 1 at a time address of 0 second, and the area A of a circle whose radius from the center of the disk 1 is r (mm) is obtained by the above equation (1). Reference numeral 32 denotes a position of the time address ta (sec) of the disk 1, and an area Aa of a circle having a radius from the center of the disk 1 as ra is obtained by the above equation (2). 33 is a time address 0 (se
Since the area is a straight line from c) to the time address ta (sec), the linear velocity v (mm / sec)
Assuming that the track pitch is d (mm), the area Aa from the equation (1) to the time address ta (sec) is obtained by the following equation.

[0041]

[Equation 11]

From equations (2) and (11), the radius ra (m) from the center of the disk 1 to the time address ta (sec)
m) is obtained by the following equation.

[0043]

(Equation 12)

The radius of the position of the current time address t1 (sec) is defined as r1 (mm), and the target time address t2 (sec) is set.
When the radius of the position c) is r2 (mm), the number of tracks DTN between the current time address and the target time address is obtained by the following equation.

[0045]

(Equation 13)

From the equations (12) and (13), the number of tracks DTN between the current time address t1 (sec) and the target time address t2 (sec) can be obtained by the following equation.

[0047]

[Equation 14]

An example of a method of calculating the measured linear velocity and the measured track pitch by the linear velocity measuring means 11 and the track pitch measuring means 13 will be described with reference to FIG.

Radius ra (mm) from the center of disk 1
When one track shift 41 is performed near 45, the time address 42 before one track shift is set to ta1 (se).
c), the time address 43 after one track shift is set to ta2 (sec), and the track shift time 44 is set to ta.
Assuming that the time is 3 (sec), the time tla (sec) for one round near the radius ra (mm) is obtained by the above equation (7).

Therefore, the radius value r from the center of the disk 1 is
(Mm) is known, and one track is shifted near 0 second, the time address before one track shift is set to ts1 (sec), and the time address after one track shift is set to ts2 (sec). Assuming that the shift time is ts3 (sec), the time tls (sec) for one round near the time address 0 (sec) is obtained from the equation (7).
It is obtained by the above equation (8).

The linear velocity of the disk 1 is set to v (mm / sec)
Then, the circumference L of the circle whose radius from the center of the disk 1 is r (mm) is obtained by the above equation (9), and the equation (9)
From equation (10), the linear velocity v (mm / sec) of the disk 1 is obtained by the above equation (10).
Gives the measured value of the linear velocity.

The radius value re from the center of the disk 1 is
One track is shifted near the last time address where (mm) is unknown, the time address before one track shift is set to te1 (sec), the time address after one track shift is set to te2 (sec), and the track shift is performed. Assuming that the time is te3 (sec), the final time address te
The time tle (sec) for one round near (sec) is obtained by the following equation.

[0053]

(Equation 15)

1 near the last time address te (sec)
The circumference Le of the circle having the radius re (mm) at the time tle (sec) of the circumference is obtained by the following equation.

[0055]

(Equation 16)

From the equations (12) and (16), the track pitch d (mm) of the disk 1 can be obtained by the following equation.

[0057]

[Equation 17]

[0058]

(Equation 18)

Therefore, the measured value of the track pitch is obtained by the equations (15) and (18). Next, an access operation according to the above embodiment will be described with reference to a flowchart shown in FIG.

The start of the disk 1 is started (step 2
0), focus / tracking /
The pull-in process of the pickup 3 is performed by the rotation servo process (step 21). Next, the track is shifted by one track near the time address 0 second by the linear velocity
Time address ts1 (sec) before this track shift
And the time address ts2 (se
c) and the track shift time ts3 (sec), the time ts (se) for one round near the time address 0 (sec).
c) is obtained by Expression (8), and the linear velocity measurement value 15 of the disk 1 is obtained from Expressions (8) and (10) and the radius value 14 at the time address 0 second (Step 22).

Next, one track is shifted near the last time address by the track pitch measuring means 13, and the time address te1 (sec) before the one track shift is obtained.
Time address te2 (sec) after one track shift
And the track shift time te3 (sec), the time tre (s) for one round near the final time address te (sec)
ec) is obtained by Expression (15), and Expressions (15) and (18) are obtained as follows:
From the linear velocity measurement value 15 of the disk 1 and the radius value 14 of the time address 0 second, the track pitch measurement value 1 of the disk 1 is obtained.
6 is calculated (step 23).

If there is an instruction to access the target time address (step 24), equation (14), the current time address t1 (sec), and the target time address t2 (s)
ec), the linear velocity measurement value 15 of the disk 1, the track pitch measurement value 16 of the disk 1, and the radius value 14 of the time address 0 second are used to calculate the number of tracks between the current and target time addresses (step 25). ), The track shift means 8 shifts the number of tracks calculated in step 25 (step 26).

It is checked whether or not the current time address after the track shift matches the target time address (step 27), and if they match, the access ends (step 2).
8) If the current time address is not equal to the target time address, the process returns to step 25 again, calculates the number of tracks, shifts the track, and repeats until the current time address becomes equal to the target time address, thereby ending the access. .

As described above, according to the above embodiment, as shown in FIG. 2, the linear velocity is obtained in the linear velocity measuring processing step 22 of the disk 1, and the track pitch is determined in the track pitch measuring processing step 23 of the disk 1. Therefore, the number of tracks between the current time address and the target time address in step 25 is calculated according to the linear velocity and the track pitch of the disk 1, and accurate calculation is performed on the disk 1 in which the linear velocity and the track pitch are different from the standard average value. Since the number of tracks can be obtained and the number of track shifts in step 26 in one access process to the target time address is reduced, there is an advantage that the access processing time can be reduced.

In the above embodiment, step 22
23 after the linear velocity measurement processing of the disk 1 by
5, the track pitch measurement process of the disk 1 may be performed after the end of the access in step 28, as shown in step 52 in FIG. In this case, the first access processing to the target time address after the start of the disk drive in step 20 does not perform the track pitch measurement processing step 23 of the disk 1 in FIG. Since the startup time of the disk device is the same as that of the conventional disk device, and the second and subsequent access processing to the target time address is performed by measuring the track pitch at step 52 at the previous access end address position. The number of tracks can be obtained accurately, and the processing time for accessing the target time address of the disk 1 is advantageously reduced.

[0066]

As described above, according to the present invention, since the linear velocity is obtained by the disk linear velocity measurement processing and the track pitch is obtained by the disk track pitch measurement processing, the access processing to the target time address of the disk is performed. In this case, the number of tracks between the current time address and the target time address is calculated according to the linear velocity and the track pitch of the disk, and the accurate number of tracks is calculated on a disk having a linear velocity and a track pitch different from the standard average value. Since the number of track shifts is reduced in the first access processing to the target time address, the access processing time can be shortened.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing a disk device according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining an access operation in the disk device.

FIG. 3 is a schematic diagram of a process of calculating the number of tracks on a disk in the disk device.

FIG. 4 is a schematic diagram of a calculation process of a linear velocity measurement value and a track pitch measurement value in the disk device.

FIG. 5 is a flowchart for explaining another access operation in the same disk device.

FIG. 6 is a schematic block diagram showing a conventional disk device.

FIG. 7 is a flowchart for explaining an access operation in the disk device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Disc 3 Pickup 7 Current time address reading means 8 Track shift means 9 Access means 10 Track number calculation means 11 Disc linear velocity measurement means 12 Track shift time measurement means 13 Disc track pitch measurement means 14 Radius value of time address 0 second 15 Measured linear velocity 16 Measured track pitch 31 Position of time address 0 32 Position of time address ta 33 Area from time address 0 to ta 41 One track shift 42 Time address ta1 before one track shift 43 One track Time address after shift ta2 44 One track shift time ta3 46 Time tra for one round near radius ra

Claims (1)

[Claims] 1. A current time address reading means for reading a time address of a current position of a disk based on a time address on a disk, a track shift means for shifting a set number of tracks on the disk, and a radius value from a center of the disk. Linear velocity measuring means for measuring the linear velocity of the disk from time addresses before and after the track shift at a known position, and track shifting at a position where the radius value from the center of the disk is unknown. Track pitch measuring means for measuring the track pitch of the disk from the previous and subsequent time addresses, and the number of tracks for obtaining the number of tracks between the current time address and the target time address of the disk from the measured values of the linear velocity and the track pitch of the disk Calculation means and the number of tracks from the calculated number of tracks Access means for accessing the target time address of the disk by setting and track shifting.