JPH0249261A - Disc motor device - Google Patents

Abstract

PURPOSE:To make the whole of a device into a thin type by using a magnet for driving a motor also as the magnet for clamping in a motor device for a disk to clamp the disk by a magnetic attractive force. CONSTITUTION:The clamping of the disk 1 is performed by also using a driving magnet 8, and by utilizing the attractive force between the magnet 8 and a disk hub 3. In other words, the hub 3 is a magnetic material, and is attracted to the magnet 8 by leakage magnetic field that flows from the magnet 8 via a turntable 14, then, the disk 1 is clamped. A mounting flange 4 holds a circuit board 7 on which a driving coil 6 is provided, and also, which forms the outer race of a motor rotating bearing 11. At the upper side of the board 7, the magnet 8 used also as the one for clamping is fixed on a driving coil yoke 5 via a rotary shaft, and is rotated by coupling with the inner race of the bearing 11.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a disk motor device in which the structure of the rotating portion and clamp portion of the disk is improved to allow for thinning and simplification.

[Conventional technology]

Optical discs are used in many information devices because of their large recording capacity. Depending on the choice of recording material, the types include magneto-optical disks, phase change reversible disks, and write-once disks. The above-mentioned optical disk is used as a compact recording device built into a personal computer or the like, but it is important to make the device thinner, and in particular, making the disk motor device thinner is a technical issue.

A conventional example of the above disk motor device is shown in FIG. This disk motor device consists of a motor section that rotates the disk 1 at, for example, 1800 rpm, and a clamp section that connects the disk 1 to the rotating section. The disk 1 is normally loaded automatically, and the clamp generally utilizes the attractive force between a clamping magnet 2 and a disk hub 3 made of a magnetic material.

The structure is as shown in Fig. 5, with a rotor of a drive magnet yoke 9 having radially magnetized drive magnets 8, and a stator wound approximately triangularly as shown in Fig. 6 for commutation. The mounting for holding the drive coil 6 having a Hall element, the printed circuit board 7, and the drive coil yoke 5 is composed of a flange 4, on which a rotating part of a turntable 14 for disc clamping is arranged, and a stator is sandwiched therebetween. The drive magnet rotor and the disk clamp rotating section are separated. The disc is clamped using a special clamp magnet 2 on the disc clamp part.
Since it is necessary to configure a closed magnetic circuit with the motor alone, an iron drive coil yoke S is mounted within the flange 4. The magnetic circuit is connected via the drive coil yoke 5.
A closed circuit is formed between adjacent different polarities of the drive magnets 8.

[Problem to be solved by the invention]

In the above conventional technology, the mounting consists of a drive magnet rotor and a disk clamp rotor with a flange 4 in between.
For installation, the drive coil yoke 5 at the bottom of the flange 4 is made of necessary iron that forms a closed magnetic circuit, and a special clamp magnet is required to clamp the disk 1, so the entire mechanism of the motor device is The disadvantages were that it was thick, had a large number of parts, and had a complicated structure. For example, the height of the disc part was 2.7 m, the rotating part was 13.4 mm, and the total height was 16.1 m.

An object of the present invention is to provide a disk motor device that clamps a disk by magnetic attraction force, which is a simpler disk clamp device than a mechanical clamp, and which enables a disk rotation mechanism that is thinner and has a simpler structure. The purpose of this invention is to obtain a motor device for use.

[Means to solve the problem]

The above object is achieved in a disk motor device that clamps a disk using magnetic attraction force, by using both the motor drive magnet and the clamping magnet, and by integrating the drive magnet rotor and the disk clamp rotating section. Ru.

In a conventional disk motor device that clamps a disk using magnetic attraction force, two magnets are used in one rotating mechanism: a motor drive magnet and a clamping magnet for clamping the disk. In the present invention, a single magnet serves as both of these two magnets, and the drive magnet rotor and the disk clamp rotation part, which were separated vertically relative to the stator of the flange, are integrated into one. In other words, in order to install a drive coil, a turntable is rotatably provided to the stator of the flange, a motor drive magnet is arranged on one side of the turntable, and a disk placed on the other side is connected to the drive magnet. The disk is clamped by the attraction force generated by the leakage magnetic field that acts on the disk hub through the turntable.

In order to clamp the disk and prevent it from coming off during rotation, a suction force of 100 g or more is required.

If the adsorption force is too large, it will be difficult to remove it, so about 200 g is preferable.3 According to one feature of the present invention, in order to obtain the above-mentioned leakage magnetic field, the material of the turntable is made of a non-magnetic material or a low-magnetic material. Made of magnetically permeable material. Examples of the nonmagnetic material or low magnetic permeability material include aluminum, brass, resin, and the like.

Additionally, in order to improve the motor characteristics, a driving magnetic yoke can be installed on the turntable. If sufficient leakage magnetic field cannot be obtained, a clamp magnet can also be placed on the surface of the turntable where the disk is placed. .

[For production]

The disk hub is attracted and fixed by the leakage magnetic field that acts on the disk hub from the motor drive magnet through the turntable, so the motor drive magnet can also be used as a clamp magnet, and the disk motor can be used as much as the clamp magnet is removed. The height of the device can be reduced, the thickness of the device can be reduced, and a device with a simplified structure can be obtained.

For example, the height of the rotating mechanism can be made thinner by about 5 ffl than in the conventional example, and a compact disk motor device can be obtained in which the overall height with the disk mounted is about 10.8 on+. Furthermore, by using both the chassis and the flange for mounting the device, the device can be further reduced in thickness and made thinner than the 10,8 cabinet.

Moreover, even when a clamp magnet is further provided, the thickness reduction is not impaired by embedding and integrating the clamp magnet into the turntable.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing one embodiment of a disk motor device according to the invention, and FIGS. 2 and 3 are sectional views showing other embodiments of the invention.

Embodiment 1 In FIG. 1, a drive magnet 8 is used to clamp the disk 1, and the attraction force between the drive magnet 8 and the disk hub 3 is utilized. That is, the disk hub 3 is made of a magnetic material (for example, iron), and the drive magnet 8
Due to the leakage magnetic field flowing through the turntable 14, the disk hub 3 is attracted to the drive magnet 8, and the disk 1 is clamped. In this embodiment, the flange 4 holds the circuit board 7 on which the drive coil 6 is mounted and forms the outer race of the motor rotation bearing 11. On the upper side of the circuit board 7, a driving magnet 8 which also serves as a clamp is fixed to the driving coil yoke 5 via a rotating shaft, and is coupled to the inner race of the bearing 11 to rotate. As described above, in this embodiment, the rotor part of the motor device integrates the drive magnet part rotor and the disk clamp rotating part, and when the disk 1 having the hub 3 made of a magnetic material is attached, the rotor part of the motor device functions as a closed magnet as a motor. It forms a circuit. That is, the magnetic circuit forms a closed circuit between adjacent different polarities of the driving magnet 8 via the metallic disk hub 3. Therefore, by mounting the disk 1, a closed magnetic circuit as a motor is configured, and the drive magnet 8
The disk 1 is attracted by the leakage magnetic field from the magnetic field. By forming the material of the turntable 14 from aluminum, which is a non-magnetic material, its attraction force is 100 g or more in vertical force.
For example, it is about 200g.

In addition, in this embodiment, the ball bearing 11, the printed circuit board 7, and the drive coil 6 are mounted to the stator of the flange 4, and the drive magnet 8 and the FG magnet 1
Turntable 14 made of aluminum with 0
is used as a rotor, and the drive coil yoke 5 is of a rotating type in order to reduce eddy current loss that occurs during motor rotation. The driving magnet 8 and the driving coil 6 are similar to the driving magnet shown in FIG. 5 and the driving coil shown in FIG. 6 in the conventional motor device.

The principle of motor rotation for the above magnetic circuit is that the rotational position of the drive magnet 8 is detected by the commutation Hall element, and the logic inside the motor control IC is used to detect the rotational position of the drive magnet 8.
As the drive magnet 8 rotates, a current is supplied to a predetermined drive coil 6, and by sequentially switching the excited coils, the motor rotates. By detecting the rotation speed of the motor as a frequency using the zigzag pattern and matching the reference frequency with the detected frequency, stable rotation of 1800 rpm and wow/flutter of 0.1% can be obtained.

In this embodiment, by using the drive magnet 8 as a clamping magnet as described above, the thickness of the rotation mechanism can be reduced by about 5 on compared to the conventional example, and the overall height of the disk motor device can be reduced. Approximately 10.8r
We were able to downsize it to r1rl.

Embodiment 2 FIG. 2 is a sectional view showing another embodiment of the present invention. In the first embodiment described above, since the drive coil yoke 5 is of the rotary type, when installed in the device, the lower part of the yoke μ coil 5 is 0.3 to 0.
A space of 5 mm is required. In this embodiment, the configurations of the magnet 8, which serves both as a drive and a disk clamp, the turntable 14, and the disk hub 3 are the same as those in the previous embodiment, but a drive coil yoke 5 is mounted below the drive coil 6, and the flange is attached to the drive coil 6. 4, and the drive coil yoke 5 is of a fixed type. Further, in some cases, by using the flange 4 for both the chassis and the mounting of the device, the overall thickness of the disk motor device can be made even thinner than the height of 10.8 m+n in the embodiment shown in FIG.

As in the first embodiment, the magnetic circuit includes a hub 3 made of a magnetic material.
A closed circuit is formed between adjacent different polarities of the drive magnets 8 via the drive magnets 8.

Embodiment 3 FIG. 3 is a diagram showing still another embodiment of the disc motor device according to the present invention, in which a clamp magnet 2 is integrated and arranged in a disc clamp section on a turntable 14 on which a driving magnet 8 is installed. It has a similar structure. If a drive magnet yoke 9 is attached to improve the motor characteristics, the leakage magnetic field from the drive magnet 8 flowing through the turntable will be reduced, and the clamping effect of the disc hub will not be sufficiently achieved. In this embodiment, the disc 1 is attracted by the magnet 2, and the clamp magnet 2 is attached to the turntable 1.
Since it is embedded in and integrated with 4, it is possible to obtain a compact disk motor device with a total height of about 10.8 mm without compromising its thinness.

〔Effect of the invention〕

As mentioned above, in the disk motor device according to the present invention, in a disk motor device that clamps a disk by magnetic attraction force, there is a limit to thinning the motor with a structure in which a magnetic circuit is formed as a single motor. Instead of configuring a closed magnetic circuit, a closed magnetic circuit is formed by attaching a disk with a hub made of magnetic material, and the disk is attracted by the attraction force of the drive magnet, which eliminates the clamp that was previously necessary. Since no magnet is required, the overall thickness of the device can be made thinner, and the structure of the motor can be simplified, so the manufacturing cost of the device can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of a disk motor device according to the present invention, FIG. 2 is a sectional view showing another embodiment of the invention, and FIG. 3 is a sectional view showing still another embodiment of the invention. cross section,
FIG. 4 is a sectional view showing a conventional disk motor device, FIG. 5 is a perspective view showing a driving magnet, and FIG. 6 is a plan view showing a portion of a driving coil. 1...Disc 2...Magnet for clamp

Claims (1)

[Scope of Claims] 1. In a disk motor device that clamps a disk to which a hub is attached by magnetic attraction force, a turntable is provided rotatably with respect to a stator of a mounting flange on which a drive coil is arranged, and the above-mentioned A drive magnet is disposed on one side of the turntable, and the disk disposed on the other side is clamped by a magnetic attraction force acting on the hub from the drive magnet through the turntable. A disk motor device, characterized in that the disk is rotated by action. 2. The disc motor device according to claim 1, wherein a clamping magnet is disposed on one side of the turntable on which the disc is disposed. 3. The disk motor device according to claim 1, wherein the turntable is made of a non-magnetic material or a low magnetic permeability material. 4. The disk motor device according to claim 1, wherein the magnetic attraction force is 100 g or more. 5. In a disk motor device that clamps a disk by magnetic attraction, a turntable is rotatably provided to a stator of a mounting flange on which a drive coil is arranged, and a motor drive magnet is mounted on one side of the turntable. A disc motor device characterized in that the motor drive magnet is also used as a magnet for clamping the disc disposed on the other side of the turntable. 6. In a disk motor device that clamps a disk by magnetic attraction, a turntable is rotatably provided to a stator of a mounting flange on which a drive coil is arranged, and a motor drive magnet is mounted on one side of the turntable. The motor drive magnet is also used as a magnet for clamping the disk placed on the other side of the turntable, and the height is set to 10.
A disc motor device characterized by having a diameter of 8 mm or less. 7. In a disk motor device that clamps a disk with a hub made of a magnetic material attached to the center by magnetic attraction force, a non-magnetic material or a low magnetic permeability material is attached to the stator of the mounting flange on which the drive coil is arranged. A turntable made of
A disc motor device characterized in that a disc clamp part is arranged on the other side. 8. The disk motor device according to claim 7, wherein the disk clamp section is configured to utilize magnetic attraction force acting on the motor drive magnet and the hub. 9. The disk motor device according to claim 8, wherein the magnetic attraction force is 100 g or more.