JPH04265596A - Optical card device - Google Patents

Abstract

PURPOSE:To prevent an objective lens from being dirty by the dust entering from a shutter part or the dust stuck to an optical card when the optical card is put in and out into and from the optical card device of the closed structure. CONSTITUTION:At the position away from an objective lens 25 of an optical card device, an air inducing port 24 to travel the space in the device near the position where a card mounting device 11 is inverted is provided at a first frame 1, an air flow in the optical card device is divided, the flow velocity is reduced, and the dirt due to the dust of the objective lens 25 can be decreased.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical card device for recording and/or reproducing information, and more particularly to a contamination prevention mechanism for an objective lens used in the optical card device.

0002

2. Description of the Related Art Optical cards have a storage capacity several thousand to ten thousand times larger than magnetic cards, and can be widely used as bank passbooks, portable maps, prepaid cards, and the like. Card devices that utilize light generally enable high-density recording, but if the optical path is blocked by dust or the like, recording and/or reproduction tends to fail due to a decrease in the amount of light. In conventional information equipment, such as hard disk drives, the inside of the device is sealed to prevent dust floating in the air from entering the device, thereby preventing the occurrence of bit errors and almost completely protecting the magnetic head. .

[0003] Sealing as in hard disk devices is also effective in optical card devices, and a structure as shown in FIG. 2 is adopted. That is, as shown in FIG. 2, a guide shaft 2 is fixed to the first frame 1, and an optical pickup 6 is movably installed along this shaft 2. A lead screw 3, a motor 4, and a worm gear set 5 are installed in the first frame 1 so as to apply thrust to the optical pickup 6. The position of the optical pickup 6 is
A set of linear encoders 7 detects the signal in the form of an electrical signal and supplies it to a control circuit (not shown) outside the device. The optical pickup 6 and the linear encoder 7 are electrically connected to the control circuit (not shown) via a flexible substrate 8. A guide shaft 10 is fixed to the second frame 9,
A card placement device (hereinafter referred to as a shuttle) 11 is movably installed along this axis 10. In order to increase the data read/write speed, it is necessary to move the shuttle 11 at high speed, so a linear motor 12 is provided on the second frame 9 as a driving source.

[0004] Also, like the optical pickup 6, the position of the shuttle 11 is detected in the form of an electrical signal by a set of linear encoders 13, and is supplied to the control circuit (not shown). The first frame 1 and the second frame 9 constitute an exoskeleton of the device, and an elastic member 14 is disposed at the joint of these frames to close the joint gap. The signal of the linear encoder 7 and the drive signal of the linear motor 12 are led out from the joint between the frames 1 and 9 to the outside of the device and supplied to the control circuit. Since it is surrounded by a sandwich-like structure, there are no gaps. The first frame 1 has a cover 1 above it.
6, and an elastic member 17 is attached to the joint portion thereof both on the first frame side and the cover side to fill the gap.

That is, these elastic members 17 sandwich the flexible substrate 8 from both the upper and lower directions, making it possible to electrically connect the inside and outside of the device without creating any gaps. Therefore, there are no holes or joints in the frames 1 and 9 that communicate the inside and outside of the device, and when the frames are joined together and the cover 16 is attached, the only opening is at the front of the device where the optical card entrance is located.

As shown in FIG. 3, on the front side of the device, gaps that occur where the frames 1 and 9 and the housing (bezel) come into contact are closed by an elastic member 19 provided on the bezel 18.

Furthermore, as shown in FIGS. 4 and 5, the bezel 1
8 is provided with an entrance 20 for the optical card 23, and this entrance 2
An elastic member 21 is attached to the back side of 0. Entrance/exit 20
A shutter 22 is disposed on the back side of the card, and the entrance/exit 20 is opened only when accepting and ejecting an optical card 23. At other times, the shutter 22 is biased by a spring (not shown) in the direction of pressing the elastic member 21 to prevent a gap from forming at the entrance/exit 20.

[0008] With the above configuration, the inside of the device can be almost completely sealed except when accepting and ejecting optical cards.

[0009]

[Problems to be Solved by the Invention] However, even with such a sealed structure, dust that adheres to the optical card and dust that enters through the shutter that is opened when the optical card is inserted into and taken out of the device can be prevented. cannot be prevented. Therefore, it is inevitable that dust will accumulate inside the device, albeit in small amounts.

As shown in FIG. 6, when the shuttle 11 makes a reciprocating motion, a portion A in the device where the shuttle 11 approaches
The air in the air is pushed by the shuttle 11 and its pressure increases. On the other hand, negative pressure will occur at the opposite position B, so
Air moves from A to B to try to balance the pressure. As a result, the air moves at high speed around the objective lens 25 located at the tip of the optical pickup 6. In addition, at this time, the air inside the device is stirred, so that dust that has adhered and accumulated on the inner walls of the device is blown up. Therefore, the objective lens 25 is exposed to the high-speed airflow containing the dust that has flown up, and the dust is reattached to its surface. As the objective lens becomes more contaminated, the intensity of the light beam irradiated onto the optical card 23 decreases, leading to a situation where the medium on the optical card does not change sufficiently during data writing, that is, data cannot be written. Also, when reading data,
The light beam reflected from the optical card to the optical pickup becomes so weak that data cannot be detected.

[0011] The present invention improves the high-speed air flow near the objective lens by providing an air flow path in the optical card device at a position away from the objective lens that connects the space near the position where the card placement device is reversed. The objective is to reduce the amount of dust in the air that adheres to the objective lens, thereby minimizing contamination of the objective lens.

0012

[Means for Solving the Problems] The present invention prevents outside air from flowing through an optical pickup device, a card placement device that carries an optical card and moves back and forth, and a mechanical section including the pickup device and the optical card placement device. An optical card device having a sealed structure for use in the present invention is characterized in that an air flow path communicating with a space near a position where the card placement device is reversed is provided at a position away from the optical pickup.

[0013]

[Operation] In the optical card device of the present invention, the objective lens 25
An air guide port 24 is provided in the first frame 1 to communicate the space inside the device near the position where the card placement device 11 is reversed at a position away from the card placement device 11, so that the air flow in the second frame 9 is directed to the first frame. The objective lens 25 of the optical pickup 6 is prevented from being contaminated by dust by dividing the flow into the optical pickup 1 and reducing its flow velocity.

[0014]

Embodiment An embodiment based on the present invention is shown in FIG. Since most of the configuration of the optical card device shown in FIG. 1 is substantially the same as that of the conventional example shown in FIGS. 2 to 6, especially FIG. 6, a detailed explanation thereof will be omitted and only the differences will be explained.

According to the present invention, an air guide port 24 in the first frame 1 is provided in the vicinity of the stroke end of the shuttle 11. When the shuttle 11 carrying the optical card 23 performs a reciprocating motion, the air in the portion A' of the apparatus where the shuttle 11 approaches is pushed by the shuttle 11 and its pressure increases.

On the other hand, since a negative pressure is generated at the opposite position B', air moves from position A' to position B' in an attempt to maintain pressure equilibrium. At this time, the passage passes through a flow path with less resistance than the narrow space sandwiched between the shuttle 11 and the first frame 1, that is, the space surrounded by the first frame and the cover 16 using the air guide port 24 as an entrance and exit, Most of the air moves. Moreover, since the flow path is wide, the velocity is smaller than the air flow that conventionally occurs near the objective lens of the device. Therefore, high-speed airflow is no longer generated near the objective lens 25 as in the conventional case. Furthermore, the reduction in air flow velocity weakens the agitation of air within the device, making it difficult for dust that has once adhered and accumulated on the inner walls of the device to fly up.

In this way, air that is cleaner than before moves around the optical pickup at a slower speed (that is, a smaller amount) than before, so the amount of dust to which the objective lens 25 is exposed is significantly reduced. As a result, the objective lens 25 has the advantage of being unaffected by contamination even when used for a longer period of time.

In this embodiment, a hole, ie, an air guide port 24, is formed in the first frame to set the flow path at a position away from the objective lens 25. Similar effects can be obtained at other locations as long as a flow path can be created. For example, the same effect as described above can be obtained by creating a tunnel in the center yoke portion of the linear motor 12 of the second frame 9 and opening both ends.

[0019]

[Effects of the Invention] As described above, according to the present invention,
It is possible to prevent the generation of high-speed airflow near the optical pickup 6, reduce the amount of dust in the air adhering to the objective lens, and reduce contamination of the objective lens.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view showing the configuration of an optical card device of the present invention.

FIG. 2 is an exploded perspective view showing the configuration of main parts of a conventional optical card device.

FIG. 3 is a perspective view showing an assembled state of a conventional optical card device.

FIG. 4(a) is a cross-sectional view showing the configuration of an optical card entrance/exit provided in the housing of the optical card device. (b) is a sectional view showing a state in which the optical card is inserted.

FIG. 5 is a perspective view of the optical card entrance/exit shown in FIG. 4;

FIG. 6 is a partially sectional side view showing the configuration of a conventional optical card device.

[Explanation of symbols]

1 First frame 2 Guide shaft 3 Lead screw 4 Motor 5 Worm gear set 6. Optical pickup 7 Linear encoder 8 Flexible board 9 Second frame 10 Guide shaft 11 Card placement device (shuttle) 12 Linear motor 13 Linear encoder 14 Elastic member 15 Flexible board 16 Cover 17 Elastic member 18 Bezel 19 Elastic member 20 Entrance/exit 21 Elastic member 22 Shutter 23. Optical card 24 Air induction port 25 Objective lens

Claims (1)

[Claims] 1. An optical card having an optical pickup device, a card placement device that carries an optical card and moves back and forth, and a sealed structure to prevent outside air from flowing through a mechanical section including the pickup device and the optical card placement device. An optical card device, characterized in that an airflow path connecting a space near a position where the card placement device is reversed is provided at a position away from the optical pickup.