JPH09275650A - Vibrationproof structure of motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dissolve the influence of vibration and noise at operation by stacking plate-shaped core plates as to a stacked core, and interposing an adhesive for damping between the core plate. SOLUTION: A stacked core 9 is constituted by stacking plural sheets of core plates 9a. Then, an adhesive 9b is interposed between the core plate 9a and the core plate 9a stacked, and the plural core plates 9a are fixed integrally by these adhesives 9b for damping so as to form a stacked core 9. Hereby, space created between each core plate 9a and the next is blocked completely, so it becomes hard for each core plate 9a to vibrate, and the noise caused by vibration can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping structure for a motor applicable to, for example, a floppy disk drive device.

[0002]

2. Description of the Related Art For example, as shown in FIG. 4, there is known a floppy disk drive motor applied to a floppy disk drive device or the like. In FIG. 4, a hole 38 formed in the center of a substrate 38 made of a magnetic material.
A bearing holder 37 is fixed to a by caulking or the like. The center portion of the bearing holder 37 is concave, and a hole 37c is formed in the center of the bottom plate 37a in this concave portion. The bearing 36 is fitted and fixed inside the concave portion of the bearing holder 37. The bearing 36 is a ball bearing, and the center hole of the inner ring of the bearing 36 is the bearing holder 3.
7 through hole 37c.

A laminated core 39 is provided on the outer peripheral surface of the bearing holder 37.
Is attached. The laminated core 39 is configured by laminating a plurality of silicon steel plates, has a plurality of radially salient poles on the outer periphery, and has a coil 4 on the arm portion of each salient pole.
0 is wound. The silicon steel plate constituting the laminated core 39 for preventing iron loss due to eddy current is 0.3
It has a thickness of 5 mm to 0.5 mm. Further, as shown in FIG. 5, each silicon steel plate to be laminated has a concave half-cut portion 39.
b and a convex portion 39a generated by forming the half-blanked portion 39b. When the silicon steel sheets are stacked, the convex portion 39a is fitted to the half-blanked portion 39b of another silicon steel sheet. The respective silicon steel plates are integrally fixed by caulking to form a laminated core 39.

On the other hand, as shown in FIG. 4, a center shaft 31 is fitted to the inner ring of the bearing 36. The central shaft 31 includes a bearing 36, a bearing holder 37, a laminated core 39, and a substrate 3.
It is rotatably supported by a stator composed of eight components. A hub base 42, on which a media hub such as a floppy disk (not shown) is mounted, is attached to the outer peripheral surface of the central shaft 31 above the bearing 36. Hub stand 4
A cup-shaped rotor case 32 is fixed to the outer edge portion of the end surface of the second bearing 36 side by caulking or the like. A support member (not shown) is attached to the surface of the rotor case 32 on the laminated core 39 side, and one end of a swing arm (not shown) is attached to the support member. The support member allows the swing arm to swing in a plane parallel to the plane of the hub base 42. A drive pin 34 is attached to the other end of the swing arm. The drive pin 34 has a hole 3 formed in the upper end surface of the rotor case 32.
It projects upward from 2a. Further, the drive pin 34 has a groove on the outer peripheral surface thereof, and this groove has a form in which a part of the rotor case 32 is bitten. Since the hole 32a is larger than the driving pin 34, the driving pin 34 is swung by the swing arm (not shown).
It can be moved within 2a.

A hub base 42 is provided on the upper surface of the rotor case 32.
And a chucking magnet 35 is attached so as to avoid the drive pin 34 protruding from the upper surface of the rotor case 32. An index magnet 43 for position detection is attached to the lower surface of the rotor case 32, that is, the surface on the laminated core 39 side.

A drive magnet 33 is attached to the inner surface of the peripheral wall of the rotor case 32. Drive magnet 3
The inner peripheral surface of 3 faces the salient poles of the laminated core 39 with a constant gap. Therefore, when the coil 40 wound around the arm of the salient pole is energized, the drive magnet 33 is urged, and the hub base 42 on which the media shaft such as the central shaft 31 and the floppy disk is mounted is rotationally driven. .

Further, a flange is formed on the peripheral wall of the rotor case 41 having the drive magnet 33 mounted on the inner peripheral surface thereof, and the frequency generating magnet 41 is mounted on the lower end surface of the flange. Also, of the substrate 38,
A frequency power generation pattern (not shown) is formed at a position facing the frequency power generation magnet 41 with a gap.

[0008]

When the coil 40 is energized to drive the motor, the coil 40 and the substrate 38 made of a magnetic material are electromagnetically coupled to each other, and as a result, the rotor case 36 vibrates to generate noise. However, since the motor for driving the above-mentioned floppy disk has a low rotation speed, the vibration and noise are so small that they can be ignored.

However, in recent years, the capacity of floppy disks has been increased and the access speed has been improved. As a result, it has become necessary to rotationally drive the disks at a high speed. However, when the motor of the floppy disk drive having the above structure is rotated at high speed, the substrate 38 by electromagnetic coupling is used.
However, there is a problem that the vibration of the machine becomes large and the noise increases.

Further, the plurality of silicon steel plates constituting the laminated core 39 are integrally fixed by half blanking, but there are gaps between the silicon steel plates one by one,
This gap causes the silicon steel plate to vibrate and generate noise.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a vibration damping structure for a motor that eliminates the effects of vibration and noise during operation.

[0012]

According to the first aspect of the present invention,
A vibration damping structure for a motor, comprising: a laminated core in which a plurality of salient poles are wound with a coil; a substrate supporting the laminated core; and a rotor having a driving magnet arranged to face the laminated core and rotationally driven. The laminated core is characterized in that flat plate-shaped core plates are laminated, and a damping adhesive is interposed between the core plates.

According to a second aspect of the present invention, there are provided a laminated core in which coils are wound around a plurality of salient poles, a substrate for supporting the laminated core, and a rotor having a driving magnet arranged to face the laminated core and rotationally driven. A vibration damping structure of a provided motor, characterized in that the substrate is formed by joining two base plates, at least one of which is a metal material, via a damping adhesive.

According to a third aspect of the invention, the vibration damping adhesive is
It is a double-sided adhesive.

The invention according to claim 4 is characterized in that the laminated core and the substrate are coupled by a fastening member.

The invention according to claim 5 is characterized in that the substrate is formed of a vibration-damping steel plate.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a vibration damping structure for a motor according to the present invention will be described below with reference to the drawings. 1 and 2 show a motor for rotationally driving a high-capacity floppy disk, which is a type of floppy disk. In FIGS. 1 and 2, the hole 13 is formed in the center of the substrate 13.
a is formed, and the bearing holder 1
The lower end protruding portion 11c of No. 1 is fitted. The bearing holder 11 includes a central cylindrical portion 11a, a flange 11b provided on the lower outer peripheral surface of the cylindrical portion 11a, a protruding portion 11c protruding downward from the cylindrical portion 11a, and a step formed on the inner peripheral surface of the cylindrical portion 11a. It is composed of each part of the part 11d. By inserting the protruding portion 11c of the bearing holder 11 into the hole 13a of the base body 13 and bringing the lower surface of the flange 11b into contact with the upper surface of the base body 13, the bearing holder 11 is moved to the base body 13
The bearing holder 11 is fixed to the base 13 by staking the above-mentioned protruding portion 11c.

A laminated core 9 is attached to the outer peripheral surface of the cylindrical portion 11a of the bearing holder 11. In FIG.
The laminated core 9 is configured by laminating a plurality of core plates 9a having the same shape of 0.35 to 0.5 mm.
A damping adhesive 9b is interposed between the laminated core plates 9a and 9a, and the plurality of core plates 9a are integrally fixed by the damping adhesive 9b to form a laminated core 9a. Are formed. As the vibration-damping adhesive 9b, for example, an epoxy-based adhesive, or a double-sided adhesive having a soft value of 70 degrees or less measured by a Barcol hardness tester is used. Further, the laminated core 9 has a plurality of salient poles on the outer periphery thereof, and the coil 8 is wound around each salient pole. In the laminated core 9, the lower surface on the inner peripheral side is in contact with the upper surface of the flange 11b of the bearing holder 11, and the tip portion of the fastening member 12 penetrating the base 13 and the flange 11b is screwed into the laminated core 9. As a result, the base body 13, the bearing holder 11, and the laminated core 9 are integrated, and the bearing holder 11 and the laminated core 9 are fixed on the base body 13. A member such as the base body 13, the bearing holder 11, and the laminated core 9 as described above constitutes a motor stator.

Further, in FIG. 1, ball bearings 10 and 10 are vertically mounted on the inner peripheral surface of the cylindrical portion 11a of the bearing holder 11 with the step portion 11d as a boundary. Cylindrical part 11
Outer rings of ball bearings 10 and 10 'are fitted and fixed to the inner peripheral surface of a. The shaft 1 is fitted and fixed to the inner rings of the ball bearings 10 and 10 '. Shaft 1 is ball bearing 1
Therefore, it is rotatable with respect to the stator.

A hub base 2 on which a medium such as a floppy disk is mounted is attached to the outer peripheral surface on the upper side of the shaft 1. A portion of the lower surface of the hub base 2 on the inner peripheral side is a protruding portion 2a protruding downward.
The lower end surface of a is in contact with the upper surface of the inner ring of the ball bearing 10.

A flat cup-shaped rotor case 6 is attached to the lower surface of the hub base 2 by caulking. The rotor case 6 has a peripheral wall on the outer peripheral side and is configured to cover the laminated core 9 from above. A drive magnet 7 is attached to the inner surface of the peripheral wall. The inner peripheral surface of the driving magnet 7 faces the tip surfaces of the salient poles of the laminated core 9 with a certain gap. Therefore, by energizing the coil 8 wound around the salient poles of the laminated core 9, the driving magnet 7 is biased in the circumferential direction, and the rotor case 6 is rotationally driven.

On the other hand, the outer edge portion of the upper surface of the hub base 2 is a disk mounting portion 2b which projects a little higher than other portions, and the hub of media such as a floppy disk is mounted on the upper end surface of the disk mounting portion 2b. Will be installed. The hub base 2 and the rotor case 6 are the turntable 3
Is composed.

A chucking magnet 4 is attached by adhesion or the like on the upper surface of the turntable 3 including the rotor case 6 and on the outer peripheral side of the hub base 2. The chucking magnet 4 has an annular shape that is concentric with the shaft 1 and has a shape in which the width in the radial direction is substantially equal over the entire circumference, that is, the outer shape is a perfect circle and the inner shape is a perfect circle. Has become. This chucking magnet 4
Then, the metal hub of the medium mounted on the hub base 2 is sucked and the medium is fixed on the hub base 2.

The rotor of the motor is composed of the shaft 1, the hub base 2, the rotor case 6, the chucking magnet 7, the driving magnet 7 and the like.

According to the motor having the above-described structure, by interposing the vibration damping adhesive 9b between the core plates 9a constituting the laminated core 9, the gaps generated between the core plates 9a Is completely closed, each core plate 9a
Is less likely to vibrate, and noise generated by the vibration can be reduced. Further, since the vibration damping adhesive 9b made of a material different from that of the core plate 9a is interposed between the core plates 9a, even if vibration occurs, the vibration damping adhesive 9b absorbs the vibration. This also makes it possible to reduce noise.

Further, since the laminated core 9 is formed by interposing the vibration damping adhesive 9b between the core plates 9a and 9a, it is not necessary to fix it by half blanking caulking, so that it is fixed by half blanking caulking. Then, even the thin core plate 9a having a problem in strength can be sufficiently used as a material of the laminated core 9.

As the vibration damping adhesive 9b, epoxy, double-sided adhesive or the like is used. Especially, the double-sided adhesive having the adhesive layers provided on both surfaces of the fiber lattice reduces a large noise. The effect can be obtained.

Next, a method of forming the laminated core 9 will be described. First, a damping adhesive 9b is coated (printed) on one surface of a sheet-shaped core material (silicon steel plate).
Next, the core material having the vibration damping adhesive 9b coated on one surface is pressed to press the core plate 9 having the vibration damping adhesive 9b.
a is formed. A plurality of such core plates 9a are laminated, and each core plate 9a is integrally fixed by the damping adhesive 9b formed on one surface to form the laminated core 9.

A method of manufacturing another laminated core 9 will be described. First, a sheet-shaped core material (silicon steel plate) is pressed to form the core plate 9a. Next, an adhesive sheet material that has been previously cured and has no adhesive property is pressed to form a vibration damping adhesive 9b having the same shape as the core plate 9a. Next, the core plate 9a-the vibration damping adhesive 9b-the core plate 9a-the vibration damping adhesive 9b-. . . To be laminated in this order to form a laminated body. Next, after heating the laminated body to melt the vibration damping adhesive 9b, the laminated body is cooled to cure the vibration damping adhesive 9b, and the plurality of core plates 1a are integrated by the vibration damping adhesive 9b. The fixed laminated core 9 is formed.

Further, another method of manufacturing the laminated core 9 will be described. A sheet-shaped core material (silicon steel plate) is pressed to form the core plate 9a. Next, the core plates 9a are laminated to form a laminated body. It should be noted that there is a gap between each core plate 9a that constitutes this laminated body. After immersing such a laminated body in a liquid adhesive, the air is removed by vacuum or the like to allow the adhesive to penetrate into the gaps between the core plates 9a to form the vibration damping adhesive 9b. The adhesive 9b is cured. By doing so, the core plate 9a is integrated and the laminated core 9 is formed.

Next, a vibration isolation structure of the motor for reducing noise generated from the substrate will be described with reference to FIG.
Since the motor of FIG. 3 has the same basic configuration as the motor of FIG. 1 described above, the same parts are designated by the same reference numerals,
Description is omitted.

In FIG. 3, the substrate 20 on which the stator of the motor such as the bearing holder 11 is attached has a three-layer structure. A portion of the substrate 20 on the stator side is a first-layer ground plate 20a, and a second layer is provided below the ground plate 20a.
A layer vibration damping adhesive 20c is formed. Further, a bottom layer 20b of a third layer is formed below the vibration damping adhesive 20c. The base plates 20a and 20b are made of a material such as aluminum, brass, plastic, or rubber.
Further, the base plate 20a and the base plate 20b are integrally fixed by a vibration damping adhesive 20c interposed therebetween to form the substrate 20. The vibration damping adhesive 20c has a value measured by a Barcol hardness meter of 7 such as an epoxy adhesive or a double-sided adhesive having adhesive parts on both sides of a fiber lattice.
A soft one of 0 degrees or less is used.

A laminated core 19 is attached to the outer peripheral surface of the cylindrical portion 11a of the bearing holder 11. The laminated core 9 is configured by laminating a plurality of core plates 19a made of magnetic plates, has a plurality of salient poles on the outer circumference, and the coil 8 is wound around each salient pole.

The lower surface of the laminated core 19 on the inner peripheral side is in contact with the upper surface of the flange 11b of the bearing holder 11,
Moreover, the substrate 20, the bearing holder 11, and the laminated core 19 are integrated by screwing the tip portion of the fastening member 12 penetrating the base 13 and the flange 11b into the laminated core 19, and the bearing holder 11 and the laminated bearing holder 11 are laminated on the substrate 20. Core 9
Has been fixed. The base member 20, the bearing holder 11, the laminated core 19 and other members constitute a motor stator.

According to the motor having the substrate 20 having the above-described structure, the vibration of the substrate 20 caused by the electromagnetic coupling between the coil 8 and the substrate 20 can be reduced by the vibration damping adhesive 20c. The generated noise can be reduced.

The base plate 20a and the base plate 20b forming the substrate 20 may be made of the same material or different materials. However, if the base plate 20a and the base plate 20b are made of different materials, the internal loss of vibration becomes large, so that the level of resonance is significantly lowered and noise can be greatly reduced. Even if the base plate 20a and the base plate 20b are made of the same material, a high vibration damping effect can be obtained depending on the type of the vibration damping adhesive 20c used.

Further, the substrate 20 is a vibration-damping steel plate (for example, VGDC manufactured by Nippon Steel Co., Ltd.) which is an iron plate that absorbs vibrations.
Series). Since the vibration damping steel plate has a vibration damping effect, the noise of the motor can be reduced.

[0038]

According to the first aspect of the present invention, the laminated core is formed by laminating the flat core plates, and the vibration damping adhesive is interposed between the core plates. ,
Each core plate is less likely to vibrate, and noise generated by the vibration of the core plate can be reduced. Further, since the vibration damping adhesive made of a material different from that of the core plates is interposed between the core plates, the vibration damping adhesive absorbs the vibrations and noise can be reduced.

According to the second aspect of the present invention, the substrate is formed by bonding two base plates, at least one of which is a metal material, through a vibration damping adhesive. It is possible to reduce the noise, and it is possible to reduce the noise generated when the motor is driven. In particular, if the two base plates are made of different materials, the internal loss of vibration becomes large, so that the level of resonance is significantly lowered, and noise can be greatly reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a vibration damping structure for a motor according to the present invention.

FIG. 2 is an enlarged cross-sectional view showing a main part of the vibration isolating structure of the motor.

FIG. 3 is a cross-sectional view showing another embodiment of a vibration damping structure for a motor according to the present invention.

FIG. 4 is a sectional view showing an example of a conventional motor.

FIG. 4 is an enlarged cross-sectional view showing a main part of the same motor.

FIG. 5 is an enlarged cross-sectional view showing a main part of the same motor.

[Explanation of symbols]

 7 Drive magnet 8 Coil 9 Laminated core 9b Damping adhesive 13 Substrate

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[Procedure amendment]

[Submission date] July 12, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a vibration damping structure for a motor according to the present invention.

FIG. 2 is an enlarged cross-sectional view showing a main part of the vibration isolating structure of the motor.

FIG. 3 is a cross-sectional view showing another embodiment of a vibration damping structure for a motor according to the present invention.

FIG. 4 is a sectional view showing an example of a conventional motor.

FIG. 5 is an enlarged cross-sectional view showing a main part of the same motor.

[Explanation of reference numerals] 7 Drive magnet 8 Coil 9 Laminated core 9b Vibration-damping adhesive 13 Substrate

Claims (5)

[Claims] 1. A motor comprising: a laminated core having coils wound around a plurality of salient poles; a substrate for supporting the laminated core; and a rotor having a driving magnet arranged to face the laminated core and rotationally driven. The vibration-damping structure is characterized in that the laminated core is formed by laminating flat core plates, and a vibration-damping adhesive is interposed between the core plates. Swing structure. 2. A motor having a laminated core in which coils are wound around a plurality of salient poles, a substrate for supporting the laminated core, and a rotor having a driving magnet arranged to face the laminated core and rotationally driven. An anti-vibration structure for a motor, characterized in that the base plate is formed by joining two base plates, at least one of which is a metal material, through a damping adhesive. 3. The vibration damping structure for a motor according to claim 1, wherein the vibration damping adhesive is a double-sided adhesive. 4. The vibration isolating structure for a motor according to claim 1, wherein the laminated core and the substrate are connected by a fastening member. 5. The vibration damping structure for a motor according to claim 2, wherein the substrate is formed of a vibration damping steel plate.