JP2703195B2 - Disc player braking system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the rotation of an optical disk in an optical disk device such as a CD-ROM drive.
LV (Constant Linear Veloci)
ty) The present invention relates to a disc player braking device employing the ty) method.

[0002]

2. Description of the Related Art Conventionally, in an optical disk device such as a CD-ROM drive, a track recorded in the circumferential direction of a disk is read while irradiating light with an optical pickup. Since the linear velocity constantly changes on the inner and outer circumferences of the disk (the linear velocity is faster on the outer circumference and slower on the inner circumference), the CLV method adjusts the number of rotations of the motor so that the linear velocity traced in a certain time is always constant. Has been adopted.

[0003] For example, CD-ROMs rotating at a high speed of 2 times or 4 times
In order to enable high-speed access by the optical pickup at the time of retrieval, cueing, and the like in the ROM device, the rotation speed of the disk must be quickly adjusted when the optical pickup moves. Therefore, it is necessary to use a motor having a high torque. Specifically, in an existing quadruple-speed CD-ROM device, a large current of about 700 mA is supplied to an expensive brushless DC motor using a rare-earth magnet at a power supply voltage of +12 V to increase the torque.

[0004]

When a motor having a high torque is used, the motor is expensive, so that the manufacturing cost is increased, and the motor is large and the apparatus becomes large. Also,
Since the power consumption of the motor is large, the temperature of the motor and the drive IC may increase significantly.

When the optical pickup moves from the outer circumference to the inner circumference of the disk, the rotation speed of the motor must be increased. However, by using an IC having a wide cap challenge, data can be read even at a low rotation speed. . However, when the optical pickup moves from the inner circumference to the outer circumference of the disk, data is read with the motor rotating at a high speed. In this case, data cannot be read unless the number of rotations of the motor is reduced to a range that can be processed by the IC.

When a motor having a low torque is used,
It takes time to reduce the number of rotations of the motor, and the access time of the optical pickup for reading data is delayed.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a disk player brake device capable of controlling the rotation speed of a motor in a short time and shortening an access time for reading disk data. It is in.

[0008]

A typical means for solving the problems of the prior art and applied to the embodiments described below is to rotate the disk in order to keep the linear velocity of the disk constant between the inner and outer circumferences. In a brake device of a disk player for controlling the number of rotations of a motor to be driven, when a reading means for reading data from the disk moves from an inner circumferential direction to an outer circumferential direction of the disk, a predetermined time is applied to a rotor of the motor. The rotation speed of the motor is adjusted to be reduced to a predetermined speed by bringing the brake pad into contact with the brake pad.

[0009]

According to the above construction, for example, the brake pad supported by the brake arm is brought into contact with the rotor of the motor for a predetermined period of time by rotating the brake arm by driving a solenoid to contact the rotor for a predetermined time. It is possible to reduce the motor to a desired rotation speed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a disc player braking device according to the present invention will be described below with reference to the drawings.
FIG. 1 is an explanatory diagram showing a schematic configuration of a brake device of a disc player, and FIG. 2 is an explanatory diagram of a solenoid drive circuit and control signals.

First, a schematic configuration of a brake device for a disc player will be described with reference to FIG. Note that a known CD-ROM device or the like is used as the disc player, and a detailed description thereof will be omitted. The following description will focus on the brake device. Reference numeral 1 denotes a spindle motor rotor as a rotor of a spindle motor (not shown).
As the spindle motor, for example, the power supply voltage is +5.
A low-cost brushed DC motor with a current consumption of about 300 mA at V is used.

Reference numeral 2 denotes a brake arm, which is supported rotatably about a fulcrum 3 provided on a frame (not shown) of the optical disk device. A brake pad 4 is attached and fixed to the brake arm 2 at a position close to and opposed to the spindle motor rotor 1. As the brake pad 4, a rubber pad or the like is used. The mounting position of the brake pad 4 is determined so that the brake pad 4 can be brought into contact with the spindle motor rotor 1 at the shortest distance from the viewpoint of speeding up the braking operation.

One end of the brake arm 2 (right side in the drawing)
, A brake return spring 5 is connected, and urges the brake pad 4 supported by the brake arm 2 in a direction away from the spindle motor rotor 1 (clockwise around the fulcrum 3). The above-mentioned brake arm 2
A solenoid 6 is connected to the other end (left side in the drawing). This solenoid 6 rotates the brake arm 2 counterclockwise around the fulcrum 3 against the elastic force of the brake return spring 5 by attracting the plunger by energization, thereby causing the brake pad 4 to contact the spindle motor rotor 1. Contact

FIG. 2A shows a drive circuit of the solenoid 6. A transistor Tr is connected to the solenoid 6, and when a control signal is input to the base of the transistor Tr, the transistor Tr is turned on and a current flows through the solenoid 6. The control signal input to the transistor Tr is a C signal (not shown).
It is input in response to a command issued from a CPU provided in the control unit of the D-ROM device.

FIG. 2B shows a control signal for driving the solenoid 6.
Indicates that the contact time with the spindle motor rotor 1 is about 5 to 30 ms. Accordingly, when an optical pickup (not shown) as a reading unit moves from the inner peripheral side to the outer peripheral side when performing a CD search, cueing, or the like, for example, in a 4 × speed mode, the CD radius is 25 mm (maximum). When moving from the inner circumference) to a radius of 58 mm (outermost circumference), the rotation speed of the spindle motor is set to about 2000 rpm or more.
It becomes possible to drop to about 860 rpm.

As a result, it is anticipated that it will be difficult to quickly control the spindle motor speed as the disk rotates at a higher speed (4 × speed, 6 × speed, etc.) in the future. By using
Since the speed control can be realized in a shorter time than when the rotation of the disk is reduced only by the motor, the access time of the optical pickup can also be reduced.

Further, since there is no need to supply a reverse current to the motor, heat generation is reduced, and it is not necessary to use a motor having an extremely high torque, which can contribute to cost reduction.

The means for contacting the brake pad 4 with the spindle motor rotor 1 is not limited to the solenoid 6, but it is also possible to bring the brake arm 2 into contact with a cam or the like by rotating the brake arm 2. is there.

The brake device according to the present invention can be effectively used not only for locating a disk, but also for stopping the rotation of the disk by stopping the drive of the device. .

[0020]

As described above, according to the present invention, when the reading means for reading data from the disk moves from the inner circumferential direction to the outer circumferential direction of the optical disk, the brake pad is brought into contact with the rotor of the motor for a predetermined time. By adjusting the rotation speed of the motor to a predetermined rotation speed, speed control can be realized in a shorter time than when the rotation of the disk is reduced only by the motor, so that the access time of the reading means can be shortened. As a result, the speed of the motor can be quickly controlled as the disk rotates at a higher speed (4 times speed, 6 times speed, etc.) in the future.

Further, since it is not necessary to supply a reverse current to the motor, heat generation of the device is reduced, and safety can be improved. Further, it is not necessary to use a motor having an extremely high torque, and the cost can be reduced. It is possible to contribute.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a brake device of a disc player.

FIG. 2 is an explanatory diagram of a solenoid drive circuit and control signals.

[Explanation of symbols]

 1 spindle motor rotor 2 brake arm 3 fulcrum 4 brake pad 5 brake return spring 6 solenoid

Claims (2)

(57) [Claims] 1. A disk player brake device for controlling the rotation speed of a motor for rotating the disk so as to keep the linear velocity of the disk constant at the inner and outer circumferences, wherein a reading means for reading data from the disk is provided. When moving from the inner circumferential direction to the outer circumferential direction of the disc, the brake pad is brought into contact with the rotor of the motor for a predetermined time,
A brake device for a disc player, wherein the rotation speed of the motor is adjusted to be reduced to a predetermined speed. 2. The brake pad is supported on a brake arm, and the brake arm is rotated by driving a solenoid to contact the brake pad with a rotor of the motor for a predetermined time. 2. The brake device for a disc player according to claim 1.