JP2000173160A - Rotation monitor mechanism and recording/reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low cost rotation monitor mechanism and a recording/ reproducing device capable of monitoring the rotation without being affected by the kind of disks. SOLUTION: The rotation monitor mechanism is furnished in a recoridng/ reproducing device which is provided with the mechanism such as the disk 990 is inserted and held between a turntable part 910 and a clamper part 170 when the disk 990 using as an information recording disk is rotated, and it is provided with the structure 175 to be detected arranged on the clamper part 170 and a sensor part 140 arranged so as to be confronted with this structure 175 to be detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a DVD, a CD-R,
A DVD device having a mechanism for clamping an information recording disk between a turntable section and a clamper section when an information recording disk such as an OM, a CD, a CD-R, and an LD rotates;
The present invention relates to recording / reproducing devices such as a ROM device, a CD device, a CD-R device, and an LD device, and a rotation monitoring mechanism provided in these devices.

[0002]

2. Description of the Related Art Conventionally, for example, in a DVD device,
A rotation monitoring mechanism for monitoring how the DVD as an information recording disk is rotating is provided. The role of the rotation monitoring mechanism is, for example, to form a signal used to detect whether or not the rotation of the DVD has reliably stopped after the user has pressed the STOP / EJECT button to remove the DVD from the DVD device.

Another role of the rotation monitoring mechanism is, for example, to form a signal used for detecting whether the rotation of the DVD is abnormally high. Still another role of the rotation monitoring mechanism is to form a signal used for the rotation servo.

A conventional rotation monitoring mechanism for this purpose is as follows.
As shown in FIG. 2 (a schematic side view schematically illustrating a rotation monitoring mechanism of a conventional recording / reproducing apparatus and a peripheral portion thereof), a turntable unit 910 that supports and rotates a disk (DVD) 990. In some cases, the rotation status of the disk 990 is indirectly detected by detecting the rotation status. This conventional rotation monitoring mechanism includes a turntable unit 910 and a DC driving the turntable unit 910.
A magnetic sensor 940 mounted on a small substrate 930 provided in a slight gap between the upper surface of the motor 920 and
A magnetic body (not shown) which is provided on the lower surface side of the turntable unit 910 and is embedded at a constant interval on a concentric circle at a position passing directly above the magnetic sensor 940. .

[0005] A reference numeral 970 in FIG. 2 is a clamper portion having a substantially man-shaped cross-section (a substantially H-shaped side). The disc 990 is sandwiched between the clamper section 970 and the turntable section 910. The clamper 970 is normally provided in a front loading DVD device.

On the lower surface side of the clamper section 970, a turn
The upper part of the convex part 910a on the center side of the table part 910 is fitted.
A recess 972 that fits is provided. This recess 972
Is usually provided with a magnet 971 (or a magnetic force of an iron plate or the like)
(A metal plate to be adsorbed) is embedded. Turntable
An iron plate 910a is provided on an upper portion of the convex portion 910a of the portion 910. ₁
(Or magnet) is attached. This magnet 971
And iron plate 910a₁Means the clamper 970 and the turn
Holds disk 990 sandwiched between cable section 910
To do this, the clamper section 970 and the turntable section 9
In order to make magnetic contact with 10 (or attract by magnetic force)
Is provided.

Reference numeral 980 denotes a chucking plate that rotatably holds the clamper 970. A main board (not shown) of the DVD device (not shown)
0) is usually provided below the DC motor 920.

When the user sets the disk 990 on the plate of the front loading mechanism (not shown) of the DVD device, the disk 990 is transported to a predetermined position on the back side by the plate. Thereafter, the DC motor 920, the turntable unit 910, and the magnetic sensor 940 mounted on the substrate 930, which were located on the lower side not in contact with the plate unit, were provided on the plate unit by a vertical movement mechanism (not shown). The inside of the opening is raised to a predetermined position (a position where the surface supporting the disk 990 of the turntable portion 910 is higher than the surface of the plate portion).

In this predetermined position, a turntable 910 is mounted on the disk 990 instead of the plate, and the lower surface of the clamper 970 is
0 is in pressure contact with the upper surface on the center side. That is, the disk 990 is sandwiched between the turntable unit 910 and the clamper unit 970. The magnetic sensor 940 of the conventional rotation monitoring mechanism detects the rotation state of the turntable unit 910 based on a change in a magnetic field from the magnetic body of the rotation monitoring mechanism provided on the lower surface side of the turntable unit 910.

Another conventional rotation monitoring mechanism is as follows.
As described in Japanese Patent Publication No. 7-56726,
In some cases, a rotation synchronization mark is attached to a disk in advance, and the rotation state of the disk itself is detected using the rotation synchronization mark. Another conventional rotation monitoring mechanism includes an optical sensor that detects the rotation synchronization mark, at a position on the lower surface side of the disk, outside the DC motor that drives the disk, and at a position where the rotation synchronization mark passes. It is provided at a relatively lower position on the lower side.

[0011]

In the case of such a conventional rotation monitoring mechanism, the rotation shaft 9 of the DC motor 920 is used.
Since an increase in the length of the length 21 causes rotation blur, the length of the rotation shaft 921 is usually as short as about 5 mm. Note that the diameter of the turntable 910 is
It is necessary not to cover the part where the 90 information is recorded. Also, the DC motor 920 is
It must be large enough to have enough torque to rotate zero. Therefore, the diameter of the DC motor 920 and the diameter of the turntable unit 910 are substantially the same. Therefore, as described above, the magnetic sensor 940 mounted on the small substrate 930 is connected to the turntable unit 910 in order to detect a change in the magnetic field from the magnetic material provided on the lower surface side of the turntable unit 910. 5 m between the top surface of the DC motor 920 that drives the turntable unit 910
It is provided in a slight gap of about m.
Therefore, an expensive Hall element is used as a thin rotation detection sensor that can be mounted on the substrate 930 (that is, the magnetic sensor 940 is a Hall element).

Accordingly, in the case of the conventional rotation monitoring mechanism,
A relatively inexpensive optical sensor could not be used, and an expensive Hall element (and an amplifier circuit for amplifying a weak Hall element signal as needed) had to be used. Further, the substrate 930 necessary for mounting the Hall element is different from the main substrate in terms of the position to be provided and the movable type. These have been obstacles to cost reduction.

On the other hand, in the case of another conventional rotation monitoring mechanism, although a relatively inexpensive optical sensor can be used, it is necessary to attach a rotation synchronization mark to the disk in advance, so that the production of the disk is It drives up costs. In addition, the rotation status cannot be detected for a disk to which the rotation synchronization mark is not attached in advance. In addition, because of the position of the optical sensor, a substrate on which the optical sensor is mounted is required separately from the main substrate, which is an obstacle to cost reduction.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a low-cost rotation monitoring mechanism and a recording / reproducing apparatus capable of monitoring rotation regardless of the type of a disk.

[0015]

According to the present invention, there is provided a rotation monitoring mechanism provided in a device having a mechanism for holding an information recording disk between a turntable section and a clamper section when the information recording disk rotates. The monitoring mechanism includes a structure to be detected provided in the clamper unit, and a sensor unit provided to face the structure to be detected.

Further, it is preferable that the sensor section is a pair of a light emitting element and a light receiving element. In this case, it is preferable that the detected structure is a light shielding plate portion and a light passing portion that are provided on the upper side of the clamper portion.

Further, it is preferable that the sensor section is provided on a main board of the apparatus.

The recording / reproducing apparatus according to the present invention may include the rotation monitoring mechanism.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rotation monitoring mechanism and a recording / reproducing apparatus according to an embodiment of the present invention will be described with reference to FIG. FIG. 1A is a schematic partial perspective view showing a rotation monitoring mechanism of a recording / reproducing apparatus according to an embodiment of the present invention and a peripheral portion thereof, and FIG. 1B is an embodiment of the present invention. FIG. 3 is a schematic plan view for explaining a rotation monitoring mechanism according to the embodiment. The same parts as those of the related art at the peripheral portions are denoted by the same reference numerals as those described above.

When the disk (DVD) 990 as an information recording disk rotates, the rotation monitoring mechanism holds the disk 990 between the turntable unit 910 and the clamper unit 17.
Front-loading type D having a mechanism for clamping with zero
It is provided in a VD device (recording / reproducing device).

First, portions related to the rotation monitoring mechanism in the DVD device will be described. The DVD device has a substantially box shape, and operation buttons (not shown) such as a Play button, a Stop button, and an Eject button are provided on a front surface thereof. On the front side of the DVD device, a plate portion of a front loading mechanism (not shown) is provided movably forward and backward. An opening is provided in the center of the dish. On the lower side where the opening is located when the plate portion is stored in the DVD device, a substantially two-stage disc-shaped turntable portion 910 having a convex portion 910a whose center is circular in plan view is provided. A DC motor 920 for driving the turntable unit 910 from below, a vertical movement mechanism (not shown) for vertically moving the two, and an optical pickup mechanism (not shown) are provided. The structure so far is exactly the same as a general DVD device.

The turntable section 910 is provided with the convex section 91.
Iron 910a ₁ is attached to the upper portion of 0a.

On the upper side of the turntable section 910, a clamper section 970 and a strip-shaped chucking plate 9 for rotatably holding the clamper section 970 are provided.
80 are provided. A main substrate 200 of the DVD device is provided above the clamper 970 and the plate 980. On the main board 200, a circuit (not shown) such as a control unit for controlling and driving the entire DVD device and a sensor unit 140 described later are mounted. Main board 200, vertical movement mechanism and plate 9
80 is fixed to a chassis (not shown) of the DVD device.

The rotation monitoring mechanism includes a sensor section 140 fixed on the upper side of the clamper section 170 and on a lower side of the main board 200 by a sensor to be detected provided on the clamper section 170 so as to face the sensor section 110. And a structure 175.

The sensor section 140 is a so-called transmission type optical sensor, and has a pair of light emitting element 140A and light receiving element 14A.
0B. The light emitting element 140A is, for example, an infrared light emitting diode, and the light receiving element 140B is, for example, a phototransistor.

The sensor section 140 is fixed to the main board 200 by soldering as described above. However, the light emitting element 140A and the light receiving element 140B have the optical axis and the lead in the same direction before molding. Therefore, the structure to be detected 175, the light emitting element 140A, and the light receiving element 14
In order to oppose OB, the lead portions of the light emitting element 140A and the light receiving element 140B are formed to be bent in a substantially L-shape. Then, the light emitting device 140 thus formed
A and the light receiving element 140B are fitted and fixed to the holder 148 so as to face each other such that the optical axes of the light receiving element 140B and the light receiving element 140B are the same. In this state, the light emitting element 140A and the light receiving element 140B are fixed to the main substrate 200 together with the holder 148 by the solder.

The structure to be detected 175 provided on the clamper 170 is provided to extend above the conventional clamper 970. The detected structure 175 is provided on an extension of the optical axis of the light emitting element 140A and the light receiving element 140B. The detected structure 175 is a light shielding plate portion 175A that is a plurality of rectangular convex portions provided at a constant pitch.
And a light passing portion 1 which is a concave portion between the light shielding plate portions 175A.
75B.

Therefore, the sensor section 140 is provided between the light emitting element 140A and the light receiving element 140B to detect the structure 17 to be detected.
No. 5 detects light passing / blocking due to alternate passage of the light passing portions 175B and the light shielding plate portions 175A.

The clamper section 170 has a lower portion 170A having a substantially man-shaped cross section (a shape in which an H-shape is laid down), and the structure to be detected extending around the upper surface of the lower portion 170A. 175.

The lower portion 170A is connected to the turntable 91.
0 presses the upper surface on the center side of the disk 990 placed on the disk 990. A concave portion 172 into which the upper side of the convex portion 910a of the turntable portion 910 is fitted is provided on the lower surface side of the lower side portion 170A. At the bottom of this recess 172,
Usually, the magnet 171 is embedded. This magnet 171
The iron plate 910a ₁ of the turntable unit 910 and,
In order to hold the disk 990 sandwiched between the clamper unit 170 and the turntable unit 910, the disk 990 is provided to bring the clamper unit 170 and the turntable unit 910 into close contact with each other by magnetic force (or to attract by magnetic force).

In such a DVD device, the rotation monitoring mechanism works as follows. The role of the rotation monitoring mechanism is to use a signal used to detect whether or not the rotation of the disk 990 has stopped reliably after the user presses the STOP / EJECT button to remove the disk 990 from the DVD device. That is, a signal used for detecting whether the rotation of the 990 is abnormally high-speed rotation and a signal used for the rotation servo are formed.

When the user presses the Eject button, the plate of the front loading mechanism projects toward the front of the DVD device. The user sets the disk 990 on the plate. Eje again by the user
When the ct button is pressed, the plate returns to its original position in the DVD device. That is, the disk 990 is transported to a predetermined position on the back side by the plate portion of the front loading mechanism. Thereafter, the DC motor 920 and the turntable unit 910, which are located on the lower side not in contact with the plate portion, move the inside of the opening provided in the plate portion by a vertical movement mechanism to a predetermined position (the position of the plate portion). Turntable unit 91 than surface
0 disk 990).

At this predetermined position, the turntable 9
10 has a disk 990 mounted thereon. In this predetermined position, the upper side of the convex portion 910a of the turntable portion 910 is fitted into the concave portion 172 on the lower surface side of the clamper portion 170, and the lower surface of the magnet 171 of the clamper portion 170 is connected to the convex portion of the turntable portion 910. It is in contact with or just before the upper surface of 910a. Since the top portion of the convex portion 910a of the turntable 910 iron plate 910a ₁ is mounted, the iron plate 910a ₁ and magnet 1
71 (or attracted) by magnetic force. Therefore, the disk 990 is sandwiched between the turntable unit 910 and the clamper unit 170.

When the Play button (not shown) is pressed by the user, the DC motor 920 starts a predetermined rotation, and the sensor unit 140 also starts working. At the start of this rotation, the clamper 170 slightly slides on the upper surface of the disk 990, so that the first minute
Although the number of rotations of the 0 and the clamper unit 170 do not slightly match, they thereafter match.

Therefore, the signal from the sensor unit 140 does not slightly coincide with the rotation speed of the disk 990 for the first minute time. However, there is no problem even if the control unit uses the signal as it is for the rotary servo since it does not slightly match. On the other hand, there is no possibility that the rotation of the disk 990 becomes abnormally high speed within the first minute time. For this reason, the control unit controls the sensor unit 14
There is no problem even if abnormal high-speed rotation is detected using the signal from 0. However, the control unit may not use the signal for the first minute time.

Next, when the Stop button is pressed by the user, the control unit supplies a reverse current to the DC motor 920 to rapidly stop the rotation of the DC motor 920. Therefore, immediately after the Stop button is pressed, the clamper 170 slightly slides on the upper surface of the disk 990 for a very short time, but thereafter, the clamper 170 and the disk 990 rotate at the same speed and stop at a reduced speed. Therefore,
The rotation speed indicated by the signal from the sensor unit 140 is slightly larger than the actual rotation speed of the disk 990 during this minute time.

However, the degree of the increase is very small and does not become larger than the rotation number immediately before the Stop button is pressed. Therefore, there is no problem even if the control unit uses the signal as it is for the rotary servo. On the other hand, there is no possibility that the rotation of the disk 990 becomes abnormally high speed within this minute time. Therefore, the control unit uses the signal from the sensor unit 140,
There is no problem even if abnormal high speed rotation is detected. However, the control unit may not use the signal for the first minute time.

When the controller presses the Eject button after judging that the signal from the sensor unit 140 is zero, the controller immediately activates the Eject function. That is, the control unit instructs the vertical movement mechanism to lower the turntable unit 910 and the DC motor 920, and advance the plate of the front loading mechanism to the front side of the DVD device. Further, the control unit is a sensor unit 14.
Before judging the signal from 0 to be the rotation speed zero, Eject
When the t button is pressed, the control unit activates the sensor unit 140
The eject function does not operate until the signal from the controller is determined to be zero in rotation speed.
The ct function works.

On the other hand, when the control unit detects the abnormal high-speed rotation state using the signal from the sensor unit 140,
Reset the power supply.

In the rotation monitoring mechanism according to the embodiment of the present invention, each of the light emitting element 140A and the light receiving element 140B is a side-view type infrared light emitting diode whose optical axis and lead are perpendicular to each other. It may be a phototransistor. In this case, a holder such as the holder section 148 may be omitted.

In the rotation monitoring mechanism according to the embodiment of the present invention, the light passing portion 175B need not be a concave portion. That is, the detected structure 175 provided in the clamper section 170
May be formed so as to extend at the same height as the light shielding plate portion 175A around the entire upper surface of the conventional clamper portion 970. In this case, the light-passing portion and the light-shielding plate portion are continuous and have the same height, and a portion that determines whether or not light passes (transmits) is formed at a constant pitch. is there. The part of whether or not this light passes (transmits)
The whole structure to be detected 175 may be transparent, and a zebra-shaped seal may be attached as a part of the structure to be detected 175. Further, the light transmitting portion and the light shielding plate portion may be formed of a light transmitting material and a light non-transmitting material, respectively.

In the rotation monitoring mechanism according to the embodiment of the present invention, the sensor section 140 may be a so-called reflection type optical sensor. In this case, the structure to be detected provided in the clamper unit may be, for example, a material having a different reflectance differently printed concentrically on the upper surface of the clamper portion, or a seal having a different reflectance differently stuck on the concentric circle. do it. Alternatively, a recessed portion and a non-dented portion may be provided on the upper surface of the clamper portion so that the reflectance differs alternately on concentric circles.

In the rotation monitoring mechanism according to the embodiment of the present invention, the sensor unit 140 may use a magnetic sensor such as a Hall element. In this case, it is preferable that magnetic materials are provided on the clamper portion at a constant interval on concentric circles.

In the above description, the detected structure is provided on the upper side of the clamper portion, but may be provided on the side surface or the like, for example. In that case, the sensor section may be provided so as to face the structure to be detected.

In the rotation monitoring mechanism according to the embodiment of the present invention, a magnet is embedded in the clamper portion, and an iron plate (of course, a metal plate other than an iron plate that is attracted by a magnetic force) is provided in an upper portion of the turntable portion. Although the magnet is attached, the magnet may be attached to the upper portion of the turntable instead of the iron plate. Further, a metal plate such as an iron plate that is attracted by a magnetic force may be embedded in the clamper portion, and a magnet may be attached to an upper portion of the turntable portion.

Although the rotation monitoring mechanism according to the embodiment of the present invention has been described as being provided in a DVD device in which the disk 990 is taken in a horizontal state, the rotation monitoring mechanism according to the present invention has a structure in which the disk 990 is vertical. For example, it may be provided in a DVD device of a type that is taken in a state other than horizontal. Further, a rotation monitoring mechanism according to the present invention may be provided in a structure in which the above-described DVD device is upside down.

[0047]

As described above, the rotation monitoring mechanism according to the present invention is provided in an apparatus having a mechanism for holding the information recording disk between the turntable and the clamper when the information recording disk rotates. A rotation monitoring mechanism provided with a structure to be detected provided in the clamper portion, and a sensor portion provided to face the structure to be detected.

In the rotation monitoring mechanism according to the present invention, the rotation state of the information recording disk is detected by the sensor unit via the clamper unit. Therefore, there is no need to previously attach a rotation synchronization mark to the information recording disk itself. Therefore, the rotation monitoring mechanism according to the present invention can monitor the rotation status of any information recording disk. In addition, the area facing the structure to be detected of the clamper part where the sensor part is provided is a part that can take a relatively large space, so there is no restriction that the sensor part must be small, and a relatively low-cost sensor should be used. Therefore, the cost of the rotation monitoring mechanism can be reduced.

The sensor section may be a pair of a light emitting element and a light receiving element. In this case, the structure to be detected may be a light shielding plate portion and a light passing portion that are provided on the upper side of the clamper portion.

In this case, since the light emitting element and the light receiving element used in the sensor section are very low-cost, the cost of the rotation monitoring mechanism according to the present invention can be reduced. Further, by using the light-shielding plate portion and the light passing portion as the structures to be detected, the SN ratio of the sensor portion can be increased. Therefore, even if the output of the light emitting element is slightly reduced due to aging, the sensor section does not hinder the output, and the life of the rotation monitoring mechanism can be extended.

Further, the sensor section may be provided on a main board of the apparatus.

In this case, the main board is provided above the clamper. Since a separate substrate on which the sensor unit is provided is not required, the cost of the rotation monitoring mechanism according to the present invention can be further reduced.

The recording / reproducing apparatus according to the present invention includes the rotation monitoring mechanism. Therefore, since the recording / reproducing apparatus according to the present invention has the effect of the rotation monitoring mechanism according to the present invention, the cost can be reduced as described above.

[Brief description of the drawings]

FIG. 1A is a diagram illustrating a recording / reproducing method according to an embodiment of the present invention.
FIG. 3 is a schematic side view partially illustrating the rotation monitoring mechanism of the reproducing apparatus and its peripheral portion, and FIG. 2B is a schematic plan view illustrating the rotation monitoring mechanism according to the embodiment of the present invention. .

FIG. 2 is a schematic partial side view explanatory view showing a rotation monitoring mechanism of a conventional recording / reproducing apparatus and a peripheral portion thereof.

[Explanation of symbols]

 140 Sensor section 170 Clamper section 175 Detected structure 990 Disc (information recording disk)

Claims (5)

[Claims] 1. A rotation monitoring mechanism provided in a device having a mechanism for holding the information recording disk between a turntable section and a clamper section when the information recording disk rotates, wherein the rotation monitoring mechanism is provided on the clamper section. A rotation monitoring mechanism, comprising: a detection structure; and a sensor unit provided to face the detected structure. 2. The rotation monitoring mechanism according to claim 1, wherein the sensor unit includes a pair of a light emitting element and a light receiving element. 3. The rotation monitoring mechanism according to claim 2, wherein the structure to be detected is a light shielding plate portion and a light passing portion extending above the clamper portion. 4. The rotation monitoring mechanism according to claim 1, wherein the sensor unit is provided on a main board of the apparatus. 5. A recording / reproducing apparatus comprising the rotation monitoring mechanism according to claim 1, 2, 3, or 4.