JP2001029889A - Cylindrical microvibration motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a large-diameter portion of a revolving shaft which withstands greater impact even when the impact is exerted thereon from the outside of a cylindrical microvibration motor as this portion has a sash weight at a portion which is large in the diameter of a shaft and is pivotally supported at a bearing. SOLUTION: The cylindrical micromotor 1 has the bearing 4 at its one end, has the sash weight 20 at the revolving shaft 3 projected with this bearing 4 and generates vibrations by rotation of the centroid of the sash weight 20 around the revolving shaft 3 together with the rotation of the revolving shaft 3. In such a case, a portion where the diameter is large and a portion where the diameter is small exist at the revolving shaft 3. The revolving shaft 3 has the sash weight 20 in the large-diameter portion and is pivotally supported at the bearing 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for producing a material having a diameter of 3 to
When a cylindrical micro-vibration motor is configured using a super-fine cylindrical micro-motor such as about 4 mm, it is used for a function of transmitting a call such as an incoming call of a mobile phone, a PHS, a pager or the like by vibration, and the like. ,
It is used for functions such as generating vibrations in game machines and having a bodily sensation effect.

[0002]

2. Description of the Related Art For example, as one prior art of the present invention, there is a cylindrical micro vibration motor invented by the present applicant and disclosed in Japanese Patent Application Laid-Open No. H11-69746.

With reference to FIG. 6, a description will be given of a cylindrical micro vibration motor which is one of the prior art. FIG. 6 shows a longitudinal sectional view of a cylindrical micro vibration motor as one of the prior arts. Incidentally, in the cylindrical micro vibration motor which is one of the prior arts, the parts common to the cylindrical micro vibration motor of the embodiment of the present invention are the same as those of the cylindrical micro vibration motor of the embodiment of the present invention. Numbering is omitted and explanation is omitted.

[0004] Cylindrical micro-vibration motors incorporated in portable telephones, PHSs, pagers and the like are ultra-fine with an outer diameter of about 4 mm. Therefore, the rotating shaft used in the cylindrical micro vibration motor has a diameter of about 0.6 mm. The rotating shaft 3-1 has a diameter of 0.6 mm, and the portion including the weight 20, the portion supported by the bearing 4, and the portion including the commutator have a diameter of 0.6 mm.

When an impact is applied to the thin rotary shaft from the outside of the cylindrical micro-vibration motor, the weight is attached to the cylindrical micro-vibration motor, the rotary shaft is swung, and the rotary shaft is bent. As a result, there is a problem that the rotation shaft does not rotate and the cylindrical micro vibration motor does not function.

[0006]

It is an object of the present invention to solve the above problems.

[Means for Solving the Problems]

In order to solve the above-mentioned problem, the invention according to claim 1 is provided with a bearing at one end of a cylindrical micromotor, a weight provided on a rotating shaft protruding the bearing, and a center of gravity of the weight being the weight. A cylindrical micro-vibration motor that generates vibration by rotating around a rotating shaft with the rotation of the rotating shaft, the rotating shaft has a large diameter portion and a small diameter portion, and has a large diameter portion. , The weight is provided, and the weight is supported by the bearing.

According to the first aspect of the present invention, since the weight is provided at the thick portion of the rotating shaft and the rotating shaft is supported by the bearing, a shock is applied from the outside of the cylindrical micro vibration motor. However, it can withstand a larger impact.

In order to solve the above-mentioned problem, the invention according to claim 2 is provided with a bearing at one end of a cylindrical micromotor, a weight provided on a rotating shaft protruding the bearing, and a center of gravity of the weight being the weight. A cylindrical micro-vibration motor that generates vibration by rotating around the rotation axis together with rotation of the rotation axis, the rotation axis having two diameters, and including the weight at a thick part. A commutator is provided at a portion having a small diameter and is supported by the bearing.

According to the second aspect of the invention, since the weight is provided at the thick portion of the rotating shaft and is supported by the bearing, a shock is applied from the outside of the cylindrical micro vibration motor. However, it can withstand a larger impact.

In addition, since the commutator is provided in the portion where the diameter of the rotating shaft is small, the outer circumference of the commutator is not increased, and the peripheral speed at the contact point between the commutator and the brush that comes into sliding contact with the commutator is suppressed. Can be. This can reduce the wear of the commutator and the brush at the contact.

Splashes from the brush commutator at the contacts cause fireworks discharge, which results in black powder containing carbon as a main component at the contacts, which prevents conduction between the brush and the commutator. . The fact that the peripheral speed at the contact point between the commutator and the brush that comes into sliding contact with the commutator can be reduced allows the splash to be reduced and fireworks discharge at the contact point can be suppressed.

According to a third aspect of the present invention, a cylindrical micromotor has a rotating shaft and a motor housing made of a magnetic material, and the motor housing is provided at both ends. A bearing for rotatably supporting the rotating shaft is provided. The field magnet and the brush are fixed inside. The rotating shaft is rotated together with the rotating shaft in a radial gap between the motor housing and the field magnet. A cylindrical micro-vibration comprising a cylindrical coreless armature, wherein a weight is provided on the rotating shaft projecting from one end of the bearing, and a center of gravity of the weight is rotated around the rotating shaft together with the rotating shaft to generate vibration. In the motor, the rotating shaft has a thick part and a thin part adjacent to each other in the axial direction, of which the weight is provided at the thick part and the commutator is supported by the bearing at the thin part. Characterized in that it comprises.

According to the third aspect of the present invention, since the weight is provided in the portion where the diameter of the rotating shaft is large and the rotating shaft is supported by the bearing, an impact is applied from the outside of the cylindrical micro vibration motor. However, it can withstand a larger impact.

Further, since the commutator is provided at the portion where the diameter of the rotating shaft is small, the outer circumference of the commutator is not increased, and the peripheral speed at the contact point between the commutator and the brush that slides on the commutator is suppressed. Can be. This can reduce the wear of the commutator and the brush at the contact.

[0016] Splashes from the brush commutator at the contacts cause fireworks discharge, which results in black powder containing carbon as a main component at the contacts, which prevents conduction between the brush and the commutator. . The fact that the peripheral speed at the contact point between the commutator and the brush that comes into sliding contact with the commutator can be reduced allows the splash to be reduced and fireworks discharge at the contact point can be suppressed.

In order to solve the above-mentioned problem, the invention according to claim 4 is characterized by comprising the following constituent elements or the like. One end side of the cylindrical micromotor of the motor housing of the cylindrical micromotor is formed in a thin outer diameter pipe shape, and a bearing house for accommodating the bearing is integrally formed and protruded outward at one end. A bearing is provided on one end side of the cylindrical micromotor of the bearing house. The field magnet is built in the motor housing. A hollow magnet holder having a restricting portion for restricting axial movement of the bearing between the bearing house and the field magnet and having a rotary shaft insertion hole extending in the axial direction. The restricting portion abuts on the other end face of the cylindrical micromotor of the bearing and the one end face of the cylindrical micromotor of the field magnet fixed to the outer periphery of the magnet holder. Restricting axial movement. A weight is provided on the rotating shaft, through which the bearing is projected through the rotating shaft insertion hole, such that the center of gravity turns around the rotating shaft. The other end of the rotating shaft on the other side of the cylindrical micromotor has a reduced diameter and includes a commutator hub and a commutator, and the cylindrical coreless armature is fixed to the commutator hub. The cylindrical coreless armature is provided so as to rotate together with the rotating shaft in a radial gap between the motor housing and the field magnet. A brush holder for holding the brush is provided at the other end of the cylindrical micromotor of the motor housing, and a bearing portion for rotatably supporting the rotating shaft is integrally formed at the center of the brush holder. That you are.

According to the fourth aspect of the present invention, since the weight is provided at the thick portion of the rotating shaft and is supported by the bearing, an impact is applied from the outside of the cylindrical micro vibration motor. However, it can withstand a larger impact.

Further, since the commutator is provided at the portion where the diameter of the rotating shaft is small, the outer circumference of the commutator is not increased, and the peripheral speed at the contact point between the commutator and the brush that comes into sliding contact with the commutator is suppressed. Can be. This can reduce the wear of the commutator and the brush at the contact.

Splashes from the brush commutator at the contacts cause fireworks discharge, which causes black powder containing carbon as a main component at the contacts to prevent conduction between the brush and the commutator. . The fact that the peripheral speed at the contact point between the commutator and the brush that comes into sliding contact with the commutator can be reduced allows the splash to be reduced and fireworks discharge at the contact point can be suppressed.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a longitudinal sectional view of a cylindrical micro-vibration motor 1, FIG. 2 is a drawing of a brush holder 17 used in the motor 1 viewed from the inside, and FIG. 3 is a brush holder used in the motor 1. Shows a longitudinal sectional view of
FIG. 4 shows the commutator 15 and the brush 16 (16-
1, 16-2) is an explanatory view, and FIG.
FIG. 3 is an explanatory diagram showing a state in which the commutator 15 is in contact with the brush 16 (16-1, 16-2).

The cylindrical micro-vibration motor 1 has a weight 2 attached to a rotating shaft 3 protruding from one end of the cylindrical micro-motor 2.
0 is fixed using means such as adhesion, press-fitting, caulking, and welding. The weight 20 has a sector shape with an opening angle of 180 degrees or less in cross section, and the rotating shaft 3 is fixed at the center of the sector shape. The weight 20 is made of a high specific heavy metal, for example, a tungsten alloy. The outer peripheral portion of the weight 20 extends in the axial direction, and the weight 20 rotates together with the rotating shaft 3 to contribute to an increase in generated vibration.

The motor housing 5 of the cylindrical micromotor 2 has a cylindrical shape, and one end is formed in a thin outer diameter pipe shape, and a bearing house 9 is integrally formed and one end protrudes outward. The motor housing 5 is made of a magnetic metal and has a function as a yoke.

A bearing 4 for supporting the rotating shaft 3 is built in one end of the bearing house 9. As the bearing 4, a sintered oil-impregnated bearing is used. In addition, a plain bearing or a ball bearing made of resin or the like can be used. The bearing 4 is fixed to the bearing house 9 by press-fitting, but there are other fixing methods such as adhesion, press-fitting, and caulking.

A magnet holder 7 is inserted into the other end of the bearing house 9. The axial movement of the bearing 4 is restricted by matching the other end surface of the bearing 4 with one end surface of the magnet holder 7. One end of the magnet holder 7 is fixed to the bearing house 9 by press-fitting, but there are other fixing methods such as bonding and caulking. The magnet holder 7 extends in the axial direction, and a rotation shaft insertion hole 19 penetrates the center portion. The magnet holder 7 has a cylindrical field magnet 10 fixed to the other end. The magnet holder 7 is fitted to the air core portion of the field magnet 10 and fixed by bonding, press fitting, or the like.

The magnet holder 7 is made of a magnetic material for the purpose of having a function as a yoke. Further, the bearing 4 and the magnet holder 7 can be integrated by using a resin or the like. The restricting portion 8 is formed integrally between the bearing house 9 of the magnet holder 7 and the field magnet 10. By contacting the motor housing 5 at one end surface of the restricting portion 8, the axial movement of the magnet holder 7 is restricted, and by contacting the field magnet 10 at the other end surface of the restricting portion 8.
Is regulated in the axial direction.

The field magnet 10 uses a samarium-cobalt magnet which is one of rare earth magnets. As another magnet, a rare earth magnet such as a neodymium-iron-boron magnet may be used. The field magnet 10 is magnetized to two magnetic poles of an N pole and an S pole so as to be adjacent in the circumferential direction. The outer diameter of the field magnet 10 is substantially the same as or larger than the outer diameter of the magnet holder 7.

The rotating shaft 3 has two tapered portions in the axial direction.
Have two different diameters. The tapered portion may be a step having an acute angle.

The diameter of the rotary shaft insertion hole 19 penetrating through the center of the magnet holder 7 is changed according to the diameter of the rotary shaft 3. In the portion where the diameter of the rotating shaft 3 is small, the diameter of the rotating shaft insertion hole 19 is reduced. Thus, the thickness of the field magnet 10 can be increased. As the thickness of the field magnet 10 increases, the obtained magnetic force increases. If the magnetic force of the field magnet 10 becomes larger, the cylindrical micro vibration motor 1 can obtain larger vibration if the flowing current is the same,
Also, less current is required to generate vibrations of the same magnitude.

A stop ring 13 is press-fitted into a portion of the rotary shaft 3 having a small diameter and protruding from the rotary shaft insertion hole 19. This is a thin iron plate. This stop ring 1
The commutator hub 14 is resin-molded so as to include the three. The commutator hub 14 is fixed to the rotating shaft 3, but uses the stop ring 13 to increase the fixing force. The stock ring 13 and the commutator hub 14 rotate together with the rotating shaft 3. The commutator hub 14 is formed by integrally molding the commutator 15. The commutator 15 is composed of five pieces, one of which is substantially L-shaped, one side of which is fixed to the commutator hub 14 and the other side of which is the outer periphery of the rotating shaft 3. The brush 16 extends along the surface in the axial direction.
A sliding contact with (16-1, 16-2) is provided.
The material of the commutator 15 is a gold alloy in order to improve the electrical conductivity at the sliding contact. Brush 16 (1
The materials 6-1 and 16-2) are also gold alloys.

The commutator hub 14 is molded from a liquid crystal polymer. A liner 12 is provided between the field magnet 10 and the magnet holder 7 and between the stop ring 13 and the commutator hub 14 in order to prevent or reduce sliding friction. The liner 12 is a thin film having excellent slidability and abrasion properties.

One end of the cylindrical coreless armature 6 is fixed to the outer periphery of the commutator hub 14. The cylindrical coreless armature 6 constitutes a coil in which a conductive wire is wound in a winding method called a “tortoise winding”. Cylindrical coreless armature 6
Are provided in a radial gap between the field magnet 10 and the motor housing 5. The cylindrical coreless armature 6 is electrically connected to the commutator 15.

The other end of the motor housing 5 is open, and a brush holder 17 is fixed to the open end. The brush holder 17 is resin-molded with a liquid crystal polymer, and has a through hole at the center thereof. The through hole serves as a bearing for rotatably supporting the rotating shaft 3.

The brush holder 17 includes two brushes 16
(16-1, 16-2) are fixed. Brush 16
A sliding contact is made by slidingly contacting the commutator 15 at the tip of (16-1, 16-2). Brush holder 1
7 fixes the lead wires 18-1 and 18-2. A lead wire 18-
Electric power is supplied to the cylindrical micro-vibration motor 1 via 1, 18-2. The lead wires 18-1 and 18-2 are
It is electrically connected to the brush 16 (16-1, 16-2).

The brush holder 17 will be described in detail with reference to FIGS. FIG. 2 is a view of the brush holder 17 viewed from the inside of the cylindrical micro vibration motor 1 in the axial direction. The brushes 16-1 and 16-2 are positioned 180 degrees symmetrically. The brush holders 21-1 and 21-2 are formed integrally with the brush holder 17. Brush 16-1, 1
6-2 is bent, and the front end is pressed against the commutator 15 using the bending pressure of the bending. The brushes 16-1 and 16-2 are brush holders 21-1, 21-
2 and is fixed. Brushes 16-1, 16-
2 form bifurcated portions 23-1 and 23-2.
-1, 24-2. Lead wires 18-1, 18
-2 conductors 22-1, 22-2 are slits 24-1,
24-2, and is fixed by welding, soldering, caulking, or the like.

A commutator 15 is provided on the outer peripheral surface of the rotating shaft 3. A sliding contact formed between the brushes 16-1 and 16-2 and the commutator 15 is formed on the outer peripheral surface of the commutator 15.
If the distance between the sliding contact and the rotation center is small, the brushes 16-1 and 16-2 and the commutator 15
Relative speed is reduced, and wear is reduced.

The commutator 15 and the brush 1 will be described with reference to FIGS.
The state of contact with 6-1 and 16-2 will be described in detail. The commutator 15 includes a first piece 29-1, a second piece 29-2, a third piece 29-3, a fourth piece 29-4, and a fifth piece 29-5. The brush tips 28-1 and 28-2 are bifurcated. This suppresses the contact area between the brushes 16-1 and 16-2 and the commutator 15 to reduce friction, and secures conductive contact by making contact at two points.

If the distance between the sliding contact and the center of rotation is small, when the sliding contact moves from one piece of the commutator 15 to another piece, the commutator of the brush tips 28-1 and 28-2. It is possible to suppress the jump from the pinion 15 and to reduce the spark discharge caused by the jump. The brush tip portions 28-1 and 28-2 are formed in an arc-shaped cross section so that the rotation center side becomes convex. This reduces the contact area between the brush tips 28-1 and 28-2 and the commutator 15,
This is for reducing the sliding friction resistance of the rotating shaft 3.

[0039]

According to the first aspect of the present invention, since the weight is provided at the thick portion of the rotating shaft and is supported by the bearing, an impact from the outside of the cylindrical micro vibration motor is provided. Even if added, it can withstand a larger impact.

According to the second aspect of the present invention, the weight is provided at a portion where the diameter of the rotating shaft is large, and the rotating shaft is supported by the bearing. Therefore, an impact is applied from the outside of the cylindrical micro vibration motor. However, it can withstand a larger impact.

Further, since the commutator is provided in the portion where the diameter of the rotating shaft is small, the outer periphery of the commutator is not increased, and the peripheral speed at the contact point between the commutator and the brush that slides on the commutator is suppressed. Can be. This can reduce the wear of the commutator and the brush at the contact.

Splashes from the brush commutator at the contact point cause fireworks discharge, which generates black powder containing carbon as a main component at the contact point, which impedes conduction between the brush and the commutator. . The fact that the peripheral speed at the contact point between the commutator and the brush that comes into sliding contact with the commutator can be reduced allows the splash to be reduced and fireworks discharge at the contact point can be suppressed.

According to the third aspect of the present invention, since the weight is provided at the thick portion of the rotating shaft and is supported by the bearing, an impact is applied from the outside of the cylindrical micro vibration motor. However, it can withstand a larger impact.

Further, since the commutator is provided at the portion where the diameter of the rotating shaft is small, the outer circumference of the commutator does not become large, and the peripheral speed at the contact point between the commutator and the brush that slides on the commutator is suppressed. Can be. This can reduce the wear of the commutator and the brush at the contact.

Splashes from the commutator of the brush at the contact point cause fireworks discharge, which causes black powder containing carbon as a main component at the contact point, which prevents conduction between the brush and the commutator. . The fact that the peripheral speed at the contact point between the commutator and the brush that comes into sliding contact with the commutator can be reduced allows the splash to be reduced and fireworks discharge at the contact point can be suppressed.

According to the fourth aspect of the present invention, since the weight is provided at the thick portion of the rotating shaft and is supported by the bearing, an impact is applied from the outside of the cylindrical micro vibration motor. However, it can withstand a larger impact.

Further, since the commutator is provided in the portion where the diameter of the rotating shaft is small, the outer periphery of the commutator is not increased, and the peripheral speed at the contact point between the commutator and the brush that slides on the commutator is suppressed. Can be. This can reduce the wear of the commutator and the brush at the contact.

Splashes from the brush commutator at the contact point cause fireworks discharge, which causes black powder containing carbon as a main component at the contact point, which prevents conduction between the brush and the commutator. . The fact that the peripheral speed at the contact point between the commutator and the brush that comes into sliding contact with the commutator can be reduced allows the splash to be reduced and fireworks discharge at the contact point can be suppressed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a cylindrical micro vibration motor 1. FIG.

FIG. 2 shows a drawing of a brush holder 17 used in the motor 1 as viewed from the inside.

FIG. 3 is a vertical sectional view of a brush holder used in the motor 1. FIG.

FIG. 4 shows a commutator 15 and a brush 16 (16) of the motor 1.
(-1, 16-2) shows an explanatory diagram.

FIG. 5 shows a commutator 15 and a brush 16 (16) of the motor 1.
(-1, 16-2).

FIG. 6 is a longitudinal sectional view of a cylindrical micro vibration motor which is one of the prior arts.

[Explanation of symbols]

 1, 1-1 Cylindrical micro vibration motor 2, 2-1 Cylindrical micro motor 3, 3-1 Rotary shaft 4, Bearing 5, Motor housing 6, Cylindrical coreless armature 7, Magnet holder 8, Regulator 9, Bearing house 10, field magnet 14, commutator hub 15, commutator 16 (16-1, 16-2), brush 17, brush 18-1, 18-2, lead wire 19, rotary shaft insertion hole 20, weight

Claims (4)

[Claims] 1. A cylindrical micromotor having a bearing at one end thereof, a rotating shaft protruding from the bearing being provided with a weight, and a center of gravity of the weight rotating around the rotating shaft together with the rotation of the rotating shaft. A cylindrical micro-vibration motor that generates vibration by the rotation shaft, wherein the rotation shaft has a large diameter portion and a small diameter portion,
A cylindrical micro-vibration motor characterized in that the large-diameter portion includes the weight and is supported by the bearing. 2. A cylindrical micromotor having a bearing at one end thereof, a rotating shaft protruding the bearing being provided with a weight, and a center of gravity of the weight revolving around the rotating shaft together with the rotation of the rotating shaft. A rotary micro-vibration motor that generates vibration by the rotary shaft, the rotary shaft has two diameters, the weight is provided with the weight at a thick portion, and the commutator is supported by the bearing at a narrow portion. A cylindrical micro vibration motor, comprising: 3. A cylindrical micromotor has a rotating shaft and a motor housing made of a magnetic material. The motor housing has bearings at both ends for rotatably supporting the rotating shaft. A magnetic core and a brush are fixed inside, and a cylindrical coreless armature that rotates with the rotating shaft is provided in a radial gap between the motor housing and the field magnet, and one end of the bearing protrudes. A rotary micro-vibration motor, wherein a weight is provided on the rotating shaft, and the center of gravity of the weight is rotated about the rotating shaft together with the rotating shaft to generate vibration. A micro-vibration motor comprising: a weight portion having a large diameter; a weight; a commutator supported by the bearing; and a commutator in a portion having a small diameter. . 4. A cylindrical micro-vibration motor comprising the following components or components. One end of the cylindrical micromotor of the motor housing of the cylindrical micromotor is formed in a thin pipe shape having a small outer diameter, and a bearing house for accommodating the bearing is integrally formed and protruded outward at one end. A bearing is provided on one end side of the cylindrical micromotor of the bearing house. The field magnet is built in the motor housing. A hollow magnet holder having a restricting portion for restricting axial movement of the bearing between the bearing house and the field magnet and having a rotary shaft insertion hole extending in the axial direction. The restricting portion abuts on the other end face of the cylindrical micromotor of the bearing and the one end face of the cylindrical micromotor of the field magnet fixed to the outer periphery of the magnet holder. Restricting axial movement. A weight is provided on the rotating shaft, through which the bearing is projected through the rotating shaft insertion hole, such that the center of gravity turns around the rotating shaft. The other end of the rotating shaft on the other side of the cylindrical micromotor has a reduced diameter and includes a commutator hub and a commutator, and the cylindrical coreless armature is fixed to the commutator hub. The cylindrical coreless armature is provided so as to rotate together with the rotating shaft in a radial gap between the motor housing and the field magnet. A brush holder for holding the brush is provided at the other end of the cylindrical micromotor of the motor housing, and a bearing portion for rotatably supporting the rotating shaft is integrally formed at the center of the brush holder. That you are.