JPH03276484A - Optical disk driving device - Google Patents

Abstract

PURPOSE:To keep the inside of a device main body in the clean state by providing a stain detecting means which optically detects the degree of stain in the device main body in accordance with the degree of scattering light due to dust in air in the device main body. CONSTITUTION:A part of the air current in a device main body 13 passes a pipe 21 and receives the emitted light from a light emitting part 22, and scattering light due to dust in air is received by a light receiving part 23. It is judged whether the output of the light receiving part 23 is larger than a threshold level or not by a first comparator 25. When the output exceeds the threshold level, an analog switch 26 is operated, and a current exceeding the threshold flows to an integrating circuit 27; and when the energy stored in the circuit 27 exceeds a reference value, a signal is outputted from a second comparator 28 to a control means 29 to operate a warning means or stop the operation of the device. Thus, the inside of the device main body is kept clean to prevent an optical means from being dirtied, and therefore, information is accurately recorded on and reproduced from an optical disk.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an optical disc drive device equipped with a drive means for recording, reproducing, and erasing information on an optical disc.

(Prior Art) A conventional optical disk drive device is provided with many driving means such as a spindle motor for rotating a disk, a seek motor for driving an optical head, and a motor for driving an objective lens. It has many heat sources such as drive circuits, control circuits, and interface circuits.

With standard drive, the temperature rise inside the device body reaches several tens of bases.

However, the optical discs and laser diodes used in optical disc drives have a maximum allowable temperature due to their durability and service life, and the above-mentioned temperature rise of several tens of bases is not acceptable. Cooling is required. The common method for this cooling is air cooling using a fan or the like, but the air outside the device body used for cooling contains a lot of dust, and this dust can cause the inside of the device body to The problem is that it gets dirty.

In particular, if dust adheres to the optical system installed inside the device main body, it may cause a decrease in recording/reproducing power or disturbance of the optical wavefront, leading to rapid deterioration of recording characteristics, reproduction characteristics, or light focusing performance. .

Therefore, as shown in Japanese Utility Model Application No. 63-29292, a dustproof cover is provided on a part of the front cover of the main body of the device where the air inlet is present, or
As shown in Japanese Patent Laid-open No. 485 and Japanese Patent Laid-open No. 63-255828, a configuration has been proposed in which the playback output from an optical disk is compared with a reference output to detect dirt inside the apparatus main body.

(Problem to be Solved by the Invention) However, in the optical disk drive device, there are many gaps through which air can flow not only in the front cover but also in other parts. It is difficult to maintain the inside of the device in a clean condition due to the increase in air flowing in from the machine and the inflow of dust that cannot be removed by the dust cover, and it is also difficult to determine the degree of dirt inside the device. Therefore, there is a problem that the inside of the device main body cannot be cleaned efficiently.

Additionally, devices that detect contamination due to dust based on playback output from optical discs only detect contamination when the inside of the device itself becomes quite dirty.
There is a problem in that there is a delay in dealing with stains.

An object of the present invention is to provide an optical disk drive device that can keep the inside of the device body clean.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an optical means for recording, reproducing, and erasing information on an optical disk, a driving means, and a device main body that takes in external air. An optical disk drive device comprising a cooling means for cooling the inside, a light emitting part provided to emit light in a direction perpendicular to the direction of air flow inside the device main body, and a light emitting part provided in a direction perpendicular to the direction of the light emission. The present invention is characterized in that it is provided with a dirt detection means comprising a light receiving section which is provided and receives scattered light from dust in the air.

(Function) By adopting the above method, the degree of contamination due to dust in the air inside the main body of the device can be measured by measuring the light emitted from the light emitting part of the contamination detection means and the light emitted from the light emitting part, but by measuring the light scattered by the dust. The light is detected optically by the light receiving section.

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

FIG. 3 is a sectional view of an embodiment of the present invention, in which 1 is an exterior cover, 2 is installed on the left side of the exterior cover 1, and includes an optical disk 3 and a spindle motor 4 which is a driving means for rotating the optical disk 3. and a drive unit body housing an optical pickup 5, which is an optical means, and a front bezel 6 provided on the left side of the exterior cover 1, in which an optical disk insertion lower and a plurality of ventilation holes 8 are formed. 9 is a dust cover attached to the front bezel 6 and has a built-in filter 10; 11 is a through hole formed in the bottom of the exterior cover 1;
12 is provided on the right side of the exterior cover 1.

A fan is a cooling means that takes air into the inside 13 of the apparatus main body through the dust cover 92 through holes 11 and the like and sends it out to the outside of the apparatus main body, 14 is a power source, and 15 is a dirt detection means to be described later.

FIG. 4 is a perspective view showing the external appearance of the drive unit main body 2, in which the front bezel 6 on the left front section includes the optical disc insertion lower, the first ventilation hole 8, the eject button 16, and an LED (light emitting diode) for display indicating the drive state. ) 17, a base 19 on which various circuit elements 18 are mounted is fixed to the upper part, and a loading mechanism 20 for the optical disc 3 is provided on the side.

FIG. 1 is a block diagram of the contamination detection means 15, in which 21 is a pipe whose axis e is parallel to the air flow A generated inside the device body 3, 22 is a light source such as a lamp, and the pipe A light emitting section installed so as to emit light in a direction a perpendicular to the axis Q of 21.

Reference numeral 23 denotes a light receiving section consisting of a photomultiplier tube or a high-sensitivity light receiving element installed in a direction perpendicular to the light emission direction a from the light emitting section 22, and 24 is installed between the light receiving section 23 and the pipe 21. 25 is a first comparator that compares the output of the light receiving section 23 with a threshold level to be described later, 26 is an analog switch operated by a signal from the first comparator 25, 27 is an integrating circuit, and 28 is an integrating lens. A second circuit that compares the output of the circuit 27 with a predetermined reference value.
A comparator 29 is a control means consisting of a CPU (central processing unit) that receives the output of the second comparator 28.

In the embodiment with the above configuration, after the optical disc 3 is inserted into the drive main body 2 from the optical disc insertion lower, the dustproof cover 9 is attached to the front bezel 6. While the optical pickup 5 is performing known recording, playback, and erasing on the optical disk 3, the fan 12 drives the inside of the main body of the device.
Intake air to 3.

Each part of the inside 13 of the apparatus main body is cooled by the air flow.

A portion of the air flow passes through the pipe 21 and receives the light emitted from the light emitting section 22 . Then, the emitted light is scattered by dust in the air, and this scattered light is received by the light receiving section 23. At the time of this light reception, the light receiving section 23 does not directly receive the emitted light from the light emitting section 22 because it is provided in a direction perpendicular to the light emitting direction a from the light emitting section 22 .

By the way, it is well known that when particles such as dust are irradiated with light, the light is scattered by the particles, and the magnitude of the scattering is proportional to the concentration of particles at the location where the light is irradiated. Therefore, as shown in the explanatory diagram showing an example of the temporal change in dust concentration shown in FIG. The waveform shown is the same as that in Figure 2 (the vertical axis represents the current).

Therefore, the first comparator 25 determines that the output of the light receiving section 23 is (
For example, with level S in Figure 2 as the threshold level),
A comparison is made to see if the value has exceeded the threshold level S, and if it has exceeded the threshold level S, the analog switch 2
6 is activated to cause a current exceeding the threshold level S to flow to the integrating circuit 27. A certain amount of energy is stored in this integration circuit 27, and the value of this energy is transferred to the second comparator 2.
8, it is compared with a standard value (for example, determined based on the measurement of dust concentration in the general environment or the performance of an optical disk drive determined in an experiment), and if it is higher than the standard value, that is, the dust concentration is high. Then.

A signal is output from the second comparator 28 to the control means 29, and the control means 29 operates, for example, a warning means (not shown) to notify the operator that the dirt due to dust inside the main body 13 of the apparatus exceeds the standard and that cleaning is necessary. Notify the user of a certain situation or stop the operation of the device.

This can prevent serious problems such as insufficient recording on the optical disc 3 and data loss caused by dust affecting the optical pickup 5.

Note that the pipe 212 of the dirt detection means 15 mentioned above
2. Light receiving section 23. The optical system consisting of the condensing lens 24 is housed in a box in a dark room to prevent the influence of external light, and the surface of the pipe 21 facing the light emitting section 22 is equipped with deflection means such as a prism or an optical fiber. By using this, the dust concentration can be detected more accurately by preventing the reflected light flux from entering the light receiving section 23.

Furthermore, the integration circuit 27 and the second comparator 28 of the dirt detection means 15 are provided to cope with the situation where the bottom of the dust box suddenly rises from time to time.

The integration circuit 27 and the second comparator 28 are omitted.

The value of threshold level S in Fig. 2 is used as a reference value.

When the dust concentration reaches the threshold level S or higher (the shaded area in FIG. 2), the first comparator 25 may output the above-mentioned warning to the control means 29 or a signal to stop the operation. ).

As a result of the above-mentioned detection of the dust concentration by the dirt detection means I5, the dust concentration increases due to the secondary scattering of dust from the filter 10 that captures dust from the outside, and the filter 1
It is also possible to determine the lifespan of 0.

Further, the dirt detection means 15 can be installed in any part of the inside 13 of the apparatus main body where an air flow occurs;
The direction and degree of air flow in step 3 may be changed as appropriate depending on specifications.

(Effects of the Invention) According to the present invention, the degree of dirt inside the device main body is optically detected by the degree of scattered light due to dust in the air inside the device main body, and the inside of the device main body is kept in a clean state. Since the optical means can be prevented from becoming dirty, it is possible to provide an optical disc drive device that can accurately and reliably record and reproduce information on an optical disc.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a dirt detection means used in an embodiment of the optical disk drive device of the present invention, FIG. 2 is an explanatory diagram showing an example of a change in dust concentration over time, and FIG. 3 is an optical disk drive of the present embodiment. A sectional view of the device, and FIG. 4 is a perspective view showing the external appearance of the drive unit main body. 2... Drive unit body, 3... Optical disk. 4...driving means, 5...optical means. 7... Optical disc insertion slot, 8... Ventilation hole, 11
. . . Through hole, 12 . . . Cooling means, 13 . . . Inside the main body of the device, 15 . 21... Pipe, 22... Light emitting section, 23... Light receiving section, 24... Condensing lens, 25... First comparator, 26... Analog switch, 27... Integrating circuit, 28... Second comparator, 29... Control means.

Claims (2)

[Claims] (1) An optical disk drive device comprising an optical means for recording, reproducing, and erasing information on an optical disk, a driving means, and a cooling means for cooling the inside of the device main body by taking in external air. A light emitting part provided to emit light in a direction perpendicular to the direction of internal air flow, and a light receiving part provided in a direction perpendicular to the direction of light emission and receiving scattered light from dust in the air. What is claimed is: 1. An optical disc drive device comprising a dirt detection means. (2) The optical disk drive device according to claim (1), further comprising a control means for stopping the operation of the device or issuing a warning when the output from the light receiving section increases above a predetermined reference value. .