JPH04349290A - Optical disk device - Google Patents

Abstract

PURPOSE:To prevent the warp of an optical disk from generating and to prevent the recording and reproducing error of information from generating by opening/ closing periodically a door attached to a cartridge port as necessary. CONSTITUTION:The level of a voltage signal is raised when detecting temperature is high. By a comparator 18, an output signal is turned on when a reference voltage V1 is exceeded by the voltage signal. By this signal, a stepping motor 6 is driven with an opening/closing repeat signal generator 19 when the repeating signal of a specified period is inputted. Thus, the forward and backward revolution of a specified angle is repeated by the stepping motor 6. Thus, a door 2 is opened/closed at the specified period and the air of the inside of the equipment is agitated. Consequently, the ambient temperature distribution of an optical disk 9a is uniform. Thus, the generation of the warp to the optical disk by the ununiformity of the ambient temperature distribution is prevented.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to various cartridge-type optical disk devices that use an optical disk or a magneto-optical disk (hereinafter also simply referred to as an optical disk) as an information recording medium.

0002

2. Description of the Related Art In an optical disc device, a laser beam is irradiated onto an optical disc when recording or reproducing information. At this time, the optical pickup that emits the laser beam and the surface of the optical disk irradiated with the laser beam generate heat. Also, the seek motor that moves the optical pickup generates heat. Furthermore, when recording information on a magneto-optical disk, the magnetic head also generates heat.

0003

Problems to be Solved by the Invention In optical disc devices, the temperature distribution within the device tends to be non-uniform because of the heat generated in each part.

[0004] Optical disks are formed into a layered structure by overlapping various materials, and each material has a different coefficient of thermal expansion.

[0005] Conventionally, therefore, there has been a problem in that during information recording/reproducing operations, the temperature distribution becomes uneven within the device, which may cause warping of the optical disc, resulting in information recording/reproducing errors. was there.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an optical disc device that can solve the above problems and prevent information recording/reproducing errors caused by warping of the optical disc.

[0007]

[Means for Solving the Problems] To this end, the present invention is characterized in that a door attached to a cartridge insertion slot into which an optical disc cartridge is inserted is configured to periodically open and close as necessary. .

[0008]

[Operation] By opening and closing the door, the air whose temperature has risen inside the device is stirred, and the temperature distribution inside the device is made uniform. This eliminates the occurrence of warping of the optical disc and prevents information recording/reproducing errors from occurring.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a front view of an optical disc device according to an embodiment of the present invention. In the figure, a front panel 1 of an optical disc device is formed with a cartridge insertion slot 1a into which an optical disc cartridge is inserted, and a door 2 is attached to that portion. this door 2
is a rectangular plate and is fixed to a shaft 3 passing through its upper part. One end of the shaft 3 is rotatably supported by a side plate 4, and the other end is supported by a gear mechanism 5.

A stepping motor 6 is disposed below the gear mechanism 5, and its shaft 6a is connected to the gear mechanism 5. At the bottom of the front panel 1 are a display 7 and operation buttons 8.
is installed.

FIG. 2 shows the inside of the gear mechanism 5. A gear 5a is fixed to the shaft 3, and the gear 5a meshes with a gear 5c fixed to the shaft 5b. The gear 5c meshes with a gear 5d fixed to the shaft 6a of the stepping motor 6.

FIG. 3 is a side sectional view of this optical disc device, showing a state in which an optical disc cartridge 9 is inserted. In the figure, the front panel 1 is fixed to one end of a lower chassis 10. As shown in FIG. On the upper surface of the lower chassis 10 is a circuit board 11 on which various electronic circuits are mounted.
and a spindle motor 12 are fixed. An optical disc 9a in an optical disc cartridge 9 is chucked onto the spindle motor 12.

A carriage 14 on which an optical pickup 13 is mounted is slidably disposed beside the spindle motor 12. A temperature sensor 15 is fixed to the side of the optical pickup 13 to detect ambient temperature. This temperature sensor 15 is, for example, a known element such as a thermistor or a thermocouple.

The above-mentioned parts are housed in a box-shaped inner chassis 16 that is open only on the door 2 side. The entire device is covered with an upper cover 17. Although not shown, in addition to the above, a seek motor for driving the carriage 14, a loading mechanism for pulling in and ejecting the optical disk cartridge 9 into the apparatus, and the like are provided in the middle chassis 16.

FIG. 4 shows a block diagram of a door drive circuit for opening and closing the door 2. As shown in FIG. In the figure, the comparator 18 includes the detection signal of the temperature sensor 15 and the reference voltage V1.
is entered. The output of the comparator 18 is input to a switching repeat signal generation circuit 19. The output and the opening/closing signal S are input to the door opening/closing control circuit 20. The stepping motor 6 is driven by the door opening/closing control circuit 20.

When using the optical disc device of this embodiment with the above configuration, the operator turns on the power of the device and inserts the optical disc cartridge 9 through predetermined operations. At this time, a predetermined opening/closing signal S is inputted to the door opening/closing control circuit 20 from a control circuit (not shown). The door opening/closing control circuit 20 then drives the stepping motor 6. As a result, the stepping motor 6 rotates by a certain angle, and the power is transmitted to the shaft 3 by the gear mechanism 5, thereby opening the door 2.

In this state, when the optical disc cartridge 9 is inserted by the operator, the loading mechanism is operated and the optical disc cartridge 9 is set in the apparatus as shown in FIG.

When the optical disc cartridge 9 is set, a predetermined opening/closing signal S is inputted to the door opening/closing control circuit 20 again, the stepping motor 6 is driven, and the door 2 is closed. The optical disc 9a in the optical disc cartridge 9 is rotationally driven by a spindle motor 12, and information is recorded and reproduced by an optical pickup 13.

By the way, during this operation, the surface of the disk 9a that is irradiated with the laser beam, the optical pickup 13, the seek motor that drives the carriage 14, etc. generate heat. As a result, the temperature below the optical disc 9a becomes higher than above.

The temperature sensor 15 detects the temperature below the optical disk 9a and outputs a voltage signal to the comparator 18 in accordance with the detected temperature. Comparator 18 compares the voltage signal with reference voltage V1.

[0022] When the detected temperature is low, the output signal of the comparator 18 is off, and the switching repeat signal generating circuit 19 does not operate. On the other hand, as the detected temperature increases, the level of the voltage signal increases. Comparator 18 turns on its output signal when its voltage signal level exceeds reference voltage V1. In response to this signal, the opening/closing repetition signal generation circuit 19 starts outputting a repetition signal of a constant period. The door opening/closing control circuit 20 is
When the repeated signal is input, the stepping motor 6 is driven in accordance with the signal. As a result, the stepping motor 6 repeats normal rotation and reverse rotation at a constant angle. As a result, the door 2 opens and closes at regular intervals, and the air inside the device is stirred.

As a result, the high temperature air below the optical disc 9a is uniformly dispersed within the apparatus, and the temperature distribution around the optical disc 9a becomes uniform. This prevents the optical disc 9a from warping due to non-uniform surrounding temperature distribution.

[0024] Next, suppose that the temperature inside the apparatus falls due to, for example, stopping the recording/reproducing operation of information or the inflow of outside air. In this case, the voltage signal level of the temperature sensor 15 decreases and the output signal of the comparator 18 is turned off. When the output signal is turned off, the opening/closing repetition signal generation circuit 19 stops generating the repetition signal with the door 2 closed. Thereby, the door 2 is held in a closed state.

Next, another embodiment of the present invention will be described.

In this embodiment, as shown in FIG. 5, in addition to the temperature sensor 15 that detects the temperature below the optical disk 9a, a temperature sensor 21 that detects the temperature above it is installed on the bottom surface of the middle chassis 16. It is installed.

Further, in the door drive circuit, as shown in FIG. 6, the detection signals of the two temperature sensors 15 and 16 are respectively input to the level difference detection circuit 22. The output of the level difference detection circuit 22 and the reference voltage V2 are input to the comparator 18.

With this configuration, in this embodiment, the temperature sensors 15 and 16 detect the temperature on both sides of the optical disk 9a during operation of the optical disk device. The level difference detection circuit 22 outputs the detected temperature difference as a voltage signal. Comparator 18 turns on its output signal when its voltage signal exceeds reference voltage V2. When the output signal of the comparator 18 is turned on, the opening/closing repetition signal generating circuit 19 and the door opening/closing control circuit 20 operate, and the opening/closing operation of the door 2 is executed as in the previous embodiment.

In this embodiment, the door 2 is opened and closed to stir the air only when the temperature difference between the two sides of the optical disk 9a in the apparatus becomes large. That is, even if a high temperature is detected, if the temperature distribution within the device is uniform, air agitation is not performed. Therefore, it is possible to prevent the door 2 from being opened/closed unnecessarily when the environmental temperature is high. Conversely, even if the environmental temperature is low, if the temperature distribution within the device becomes uneven, air is stirred to prevent the optical disc 9a from warping. .

Note that in each of the above embodiments, the temperature sensor 1
5 and 21, the detected temperature is output as a voltage signal and a predetermined control is performed based on the voltage signal. However, for example, the detected temperature is extracted as a contact signal using a bimetal, and the detected temperature is output as a contact signal. Similar control can also be performed based on

[0031]Although the explanation has been given using an example of an optical disk as an information recording medium, it goes without saying that the same applies to a case where a magneto-optical disk is used.

[0032]

As described above, according to the present invention, the door attached to the cartridge insertion slot is opened and closed periodically as needed, so the air inside the device is stirred and the temperature is lowered. Since the distribution is made uniform, warping of the optical disc is eliminated, and information recording/reproducing errors can be prevented from occurring.

[Brief explanation of drawings]

FIG. 1 is a front view of an optical disc device according to an embodiment of the present invention.

FIG. 2 is an internal front view of the gear mechanism.

FIG. 3 is a side sectional view of the optical disc device.

FIG. 4 is a block diagram of a door drive circuit.

FIG. 5 is a side sectional view of the optical disc device according to another embodiment of the present invention.

FIG. 6 is a block configuration diagram of a door drive circuit in the above embodiment.

[Explanation of symbols]

1 Front panel 1a Cartridge insertion slot 2 Door 3,6a axis 4 Side plate 5 Gear mechanism 6 Stepping motor 9 Optical disc cartridge 9a Optical disc 10 Lower chassis 12 Spindle motor 13 Optical pickup 14 Carriage 15, 21 Temperature sensor 18 Comparator 19 Opening/closing repetitive signal generation circuit 20 Door opening/closing control circuit 22 Level difference detection circuit

Claims (3)

[Claims] 1. An optical disc device in which a door is attached to a cartridge insertion slot into which an optical disc cartridge is inserted, characterized in that the optical disc device is provided with a door driving means for periodically opening and closing the door as required. Device. [Claim 2] A claim characterized in that the device comprises temperature detection means for detecting the temperature inside the device, and control means for causing the door driving means to operate when the detected temperature exceeds a certain value. Item 1. The optical disk device according to item 1. 3. Temperature detection means for detecting the temperature inside the apparatus at positions on the upper surface side and lower surface side of the optical disk in the inserted optical disk cartridge; 2. The optical disk device according to claim 1, further comprising control means for causing the door driving means to operate when the difference exceeds a certain value.