JPH0384768A - Optical disk device - Google Patents

Abstract

PURPOSE:To effectively prevent a temp. rise in the subject device and also to reduce the access time of an optical head for making its high speed by controlling an electric current to be supplied to a linear motor based on a temp. obtained by a temp. sensor with a drive controller. CONSTITUTION:The optical disk device is provided with the temp. sensor 9, and the current to flow into the linear motor 7 is controlled based on a temp. detected by this temp. sensor 9. Consequently, the temp. in the device can be maintained below a fixed temp. by suppressing heating of the linear motor 7 in making a driving current to flow into the linear motor 7 diminised when the temp. in the device exceeds a certain value. By this method, heat susceptible parts, such as a semiconductor laser and an optical disk, etc., can be prevented from deteriorating, while the access time of the optical head 4 can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an optical disc device for recording and reproducing code data, images, audio, etc.

2. Description of the Related Art Conventionally, this type of optical disk device has an optical system that includes an optical system equipped with an objective lens, etc., which generates a light spot of a semiconductor laser on a recording medium, and an electromagnetic drive system, etc., which positions the light spot in a minute range at high speed. From the head, a linear motor that moves the optical head to a target position on the recording medium, an electromagnetic motor that rotates the recording medium, and a drive controller that controls the driving of the optical head and each motor as well as signal processing, etc. Become.

Optical heads are often driven by linear motors in order to shorten access time, and are usually driven by passing a current within a certain allowable range. Further, since the semiconductor laser in the optical disc device and the optical disc as the recording medium are sensitive to heat, the temperature environment in which they can be used is limited.

However, recently, in order to further shorten the access time, a large amount of current has been passed through the linear motor, which can cause the temperature inside the optical disk device to rise and exceed the operating temperature for semiconductor lasers and optical disks. be. Conventionally, therefore, a cooling device such as a fan was installed to limit the maximum current flowing through the linear motor to prevent the temperature from rising.

Problems to be Solved by the Invention However, among the conventional methods of preventing temperature rise inside optical disk devices, the method of limiting the maximum current flowing to the linear motor does not contribute to speeding up the access time of the optical head. There is a problem that it cannot be done. Furthermore, the method of cooling using a fan or the like has the problem that dust and the like are blown onto the lens of the optical head and the optical disk, degrading the optical characteristics of the device.

The present invention solves the above-mentioned problems, and aims to provide an optical disk device that can effectively prevent temperature rise within the device and contribute to speeding up the access time of an optical head.

Means for Solving the Problems In order to achieve the above object, the present invention provides a temperature sensor within an optical disk device, and controls the current flowing to the linear motor based on the temperature detected by the temperature sensor. It is.

Therefore, according to the present invention, when the temperature inside the device exceeds a certain value, the drive current applied to the linear motor is reduced to suppress the heat generation of the linear motor, thereby keeping the temperature inside the device below a certain temperature. I can do it. This has the effect of preventing deterioration of heat-sensitive components such as semiconductor lasers and optical disks, and shortening the access time of the optical head.

The embodiment diagram schematically shows the configuration of an embodiment of the present invention. In the figure, 1 is an ESDi interface, 2 is a drive controller that controls the entire optical disk device,
3 is a laser drive circuit for driving the semiconductor laser of the optical head, and 4 is an optical head, which includes an optical system such as a semiconductor laser and an objective lens, and an electromagnetic drive system for supporting these optical systems and performing focusing and tracking. ing. 5 is an amplifier for amplifying the signal read by the optical disc 4; 6 is a signal processing circuit for processing the signal amplified by the head amplifier 5; 7 is a linear unit for moving the optical head 4 at high speed in the radial direction of the optical disc. Motor, 8 is optical disk 4
9 is a temperature sensor provided in the device; 10 is a control circuit that controls the rotation of a spindle motor that rotates the optical disk; 11 is a control circuit that controls the rotation of the spindle motor that rotates the optical disk; A control circuit for the loading mechanism for ejecting the disc, and 12 are the identifiers of the cartridges containing the optical discs.

Next, the operation of the above embodiment will be explained. The ESDi interface 1 is connected to the drive controller 2 by a pass line 13, and the ESDi interface 1
All signals input and output through the drive controller 2 are controlled by the drive controller 2. Also, a laser drive circuit 3, a signal processing circuit 6, a servo circuit 8, a temperature sensor 9, a spindle motor control circuit 10. Loading mechanism control circuit 11
and cartridge identifier 12 are also controlled by drive controller 2.

When recording, the semiconductor laser of the optical head 4 is modulated by the laser drive circuit 3 in response to a signal from the ESD i-interface 1, and the optical head 4 is moved in the radial direction by the linear motor 7 while driving the modulated light spot onto the spindle. The motor control circuit 10 irradiates the surface of the rotating optical disk to form a pit array thereon in accordance with the input signal.

When reproducing, the optical head 4 moves the surface of the optical disk rotating by the spindle motor control circuit 10 in the radial direction by the linear motor 7, optically reading the bit string on the surface of the optical disk and converting it into an electric signal, which is then sent to the head amplifier. 5 and processed by the signal processing circuit 6.
Output via i-interface 1.

The temperature inside the apparatus rises due to the heat generated by the linear motor 7 that drives the optical head 4, which is supplied with a large capacity current for high-speed access, among several heat generating elements. When the temperature inside the device exceeds a certain set value that adversely affects the semiconductor laser of the optical head 4 and the optical disk, the temperature sensor 9 detects the temperature and outputs a signal to the drive controller 2. Based on this signal, the drive controller 2 reduces the drive current flowing to the linear motor 7 via the servo circuit 8 to a certain value to suppress heat generation in the linear motor 7. As a result, when the temperature inside the device falls below a certain set temperature, the drive controller 2 returns the drive current supplied to the linear motor 7 to the original large capacity current in response to a signal from the temperature sensor 9, thereby reducing the access time. Try to speed it up.

Effects of the Invention As is clear from the above embodiments, the present invention detects the temperature inside the optical disk device and controls the current flowing to the linear motor that generates a large amount of heat. This has the advantage that deterioration can be prevented and the access time of the optical head can be increased.

[Brief explanation of drawings]

The figure is a schematic block diagram showing the configuration of an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... ESD i interface, 2... Drive controller, 3... Laser drive circuit, 4... Optical head, 5... Head amplifier, 6... Signal processing circuit,
7... Linear motor, 8... Servo circuit, 9...
Temperature sensor 10... spindle motor control circuit,
11... Loading mechanism control circuit, 12... Cartridge identifier, 13... Pass line.

Claims (1)

[Claims] An optical head that reproduces and/or records signals from a recording medium, a linear motor that drives the optical head, an electromagnetic motor that rotates the recording medium, and controls driving and signal processing of the optical disk and each of the motors. An optical disc device comprising: a drive controller; and a temperature sensor that detects a temperature inside the device, the drive controller controlling a current supplied to the linear motor based on the temperature obtained by the temperature sensor.