JPH1169746A - Tubular micro oscillation motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ultrathin tubular micro oscillation motor producing a large oscillation while limiting the overall length. SOLUTION: One end part of a motor housing 3 is formed into a fine pipe and a bearing house 5 for housing a bearing 4 is formed integrally while projecting one end outward. A protrusion 6 for regulating axial movement of the bearing 4 is provided between the bearing house 5 and a field magnet 9. An oscillation generating eccentric weight 11 of reverse L-shaped cross-section having outside diameter substantially equal to or smaller than that of the motor housing 3 is fixed to a shaft 10 passed through the axially extending shaft insertion hole 7 of a hollow stator yoke 8 while projecting one end part from the bearing house 5 such that the extended bend 12 thereof faces the bearing house 5 having thin outside diameter and the outer circumferential part of the motor housing 3 continuous thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a diameter of 3 to 4 m.
In the case of forming a cylindrical vibration motor using an ultra-fine cylindrical micromotor such as m, a cylindrical microvibration motor in which the vibration motor is short and large in the axial direction can be obtained. (Paging device), massager, vibration alarm device such as mobile phone, etc. are used for devices requiring a vibration source.

[0002]

2. Description of the Related Art For example, in a pager (so-called a pager) or a portable telephone, in order to notify that a telephone call has been made, in recent years, it has been selected to use a vibration method instead of a sound. Have been. A pager, a cellular phone, or the like of a type that generates this vibration has a built-in cylindrical micro vibration motor.

[0003] In recent years, the size of a pager or a cellular phone has become smaller and lighter, so that the diameter is 3 to 4 mm.
It is advisable to use an ultra-fine cylindrical micro vibration motor.

In an ultra-fine cylindrical micro-vibration motor having a diameter of 3 to 4 mm, a shaft protruding from one end of the ultra-fine cylindrical micro motor has a vibration having an open angle width of 180 degrees or less in a circumferential direction. The generation eccentric weight is fixed.

When the shaft rotates, the eccentric weight rotates with partial circular eccentricity, and the vibration is transmitted to the motor casing of the cylindrical micromotor. Therefore, the case of a pager or a cellular phone housing the cylindrical microvibration motor with the eccentric weight is built in. The vibration propagates to the body, and a person wearing a pager or a mobile phone feels the vibration and can know that there is a telephone call.

Here, in the case of the cylindrical micro-vibration motor, when its length is limited, a shaft slightly protruding from one end of the cylindrical motor casing of the cylindrical micro-motor has a small plane semicircle having the same radius as that of the cylindrical micro-motor. The eccentric weight cannot be extended in the axial direction, and a large vibration cannot be obtained due to insufficient weight.

In order to obtain a super-fine cylindrical micro-vibration motor capable of obtaining a large vibration, it is necessary to rotate the motor at a high speed and to use a heavy eccentric weight for generating vibration which is long in the axial direction. There is.

When such a motor is rotated at a high speed, an eccentric weight for generating a heavy vibration whose length is increased in the axial direction is used, and an extremely thin shaft having a small radius is used. Shaft bending occurs, starting failure of the cylindrical micro vibration motor occurs,
fall into disrepair. Further, when the eccentric weight which is long in the axial direction and heavy is used, there is a disadvantage that the vibration motor becomes long in the axial direction.

Particularly, in the case of a pager or a cellular phone using such a cylindrical micro vibration motor, if a drop or an impact from the outside is applied, a shaft bend protrudes from one end of the cylindrical micro vibration motor body. In addition, there is a disadvantage that starting failure of the cylindrical micro-vibration motor occurs and the possibility of damage is further increased.

More specifically, the structure of a conventional vibration motor will be described with reference to FIGS.

A cylindrical micro vibration motor 1 'shown in FIG.
Is formed by extending a central portion of one end of the motor housing 3 'inwardly to form a bearing house support portion 5', and a bearing house 8 'integrally formed with the stator yoke 8' in the bearing house support portion 5 '. a, and the bearing 4 is inserted into the bearing house 8'a. The axial movement of the bearing 4 is regulated by the bearing house 8'a.

Reference numeral 2 'indicates a cylindrical micromotor, 9 indicates a field magnet, 10' indicates a shaft, and 11 'indicates an eccentric weight 11' attached to the shaft 10 '.

Another conventional cylindrical micro-vibration motor 1 ″ uses a cylindrical motor housing 3 ″ as shown in FIG. 8, and has a lid / stator yoke for closing one end opening. 8 ", the recess formed at the upper end of the stator yoke 8" is used as a bearing house 5 ", and the bearing 4 is inserted into the recess for the bearing house 5" to rotate the shaft 10 '. It is movably supported. 2 ″ indicates a cylindrical micromotor.

[0014]

In each of the conventional cylindrical micro vibration motors 1 'and 1 "shown in FIGS. 7 and 8, the total length of the cylindrical micro vibration motors 2' and 2" is limited. In this case, as described above, the eccentric weight 11 ′ can be used only in a short length in the axial direction, and has a disadvantage that large vibration cannot be obtained.

If an eccentric weight 11 'which is long in the axial direction is used in order to obtain a large vibration, only a cylindrical micromotor 2' having a short length in the axial direction can be used this time. The vibration motor 1 '
And 1 '' cannot be rotated at a high speed, and a large amount of vibration cannot be obtained.

[0016]

SUMMARY OF THE INVENTION The object of the present invention is as follows.
One end of the motor housing 3 of the cylindrical micromotor 2 is formed in a thin outer diameter pipe shape, and a bearing house 5 for accommodating the bearing 4 is integrally formed and protruded outward at one end. A hollow stator having a built-in bearing 4, a projection 6 for restricting axial movement of the bearing 4 between the motor housing 5 and the field magnet 9, and having a shaft insertion hole 7 extending in the axial direction. The projection 4 of the stator yoke 8 is located between the other end surface of the bearing 4 and one end surface of a field magnet 9 fixed to the outer periphery of the stator yoke 8. The axial movement of the magnet 9 is restricted, and the shaft insertion hole 7 is restricted.
Shaft 10 protruding at one end of bearing house 5
A vibration generating eccentric weight 11 having an outer diameter substantially equal to or smaller than the outer diameter of the motor housing 3 and having an inverted L-shaped longitudinal section is attached to the motor housing 3. This can be achieved by providing a cylindrical micro-vibration motor in which an extended bent piece 12 formed by further extending a part of the portion toward the lower end portion is opposed to the outer peripheral portion of the bearing housing 3 having a small outer diameter. .

[0017]

In the cylindrical micro-vibration motor 1 of the present invention, the bearing 4 mounted in the bearing house 5 on the side of the eccentric weight 11 and the stator yoke 8 serving also as a magnet holder are coaxially arranged in parallel with the motor housing 3. The extended bent piece 12 of the eccentric weight 11 can be opposed to the outer periphery of 5.

Since the eccentric weight 11 has an inverted L-shape, the eccentric weight 11 can protrude from the eccentric weight 11 by the length of the bearing 4 in the axial direction. That is, it is not necessary to shorten the length of the portion required for generating torque in the cylindrical micromotor 2, in other words, it is not necessary to substantially change the overall length of the cylindrical micromotor 2 in the axial direction, and it is large. Since the eccentric weight 11 having a long length in the axial direction can be used to obtain the vibration, a larger vibration can be obtained as the cylindrical micro-vibration motor 1 whose length is limited.

In addition, the eccentric weight 11 has an inverted L-shape, and the bearing house 5 and the bearing 4 are located in the concave portion 13, but the concave portion 13 does not contribute to vibration, Conversely, since the portion is inversely proportional to the increase in the vibration, the provision of the concave portion 13 has an effect that a larger vibration can be obtained.

The eccentric weight 11 can be formed to have a longer axial length without limiting the overall length of the cylindrical micromotor 2, so that the weight of the eccentric weight 11 can be increased, and the eccentric weight 11 can be increased in the axial direction. It is designed not only to increase the length but also to obtain a larger vibration, and it is possible to generate a larger vibration as compared with the conventional one.

In addition, in the case of a cylindrical micro-vibration motor having a very fine shape such as Φ3 to φ4, the shaft used for this motor has a small radius, so that simply extending the eccentric weight in the axial direction has the advantage that a large vibration can be obtained. However, because the shaft is extremely thin, if it is simply formed long in the axial direction, if a pager or mobile phone with a built-in cylindrical micro-vibration motor is dropped, the eccentric weight is made of a heavy alloy such as tungsten. Bend, the shaft will bend, the eccentric weight will not rotate,
In the case of the cylindrical micro vibration motor 1, the center of gravity W of the eccentric weight 11 is the upper surface of the bearing 4, that is, between the center of gravity W and the upper surface of the bearing 4. Is close to the distance L, so that it is resistant to the drop impact as described above, and it is possible to prevent the cylindrical micro vibration motor 1 from being unable to start due to bending of the shaft 10 or the like.

Particularly, regarding the bending of the shaft, the distance between the lower end portion of the extended bent portion 12 and the upper end surface of the motor housing 13 can be maintained at a distance which can be held down to the bending within which the bending of the shaft occurs.

[0023]

FIG. 1 is a longitudinal sectional view of a cylindrical micro-vibration motor 1 of the present invention, FIG. 2 is an explanatory view when a brush holder 14 is viewed from the inner surface direction, and FIG. FIG. 4 is a side longitudinal sectional view of the brush holder 14, FIG. 4 is an explanatory diagram of a contact relationship between the commutator 15 and the brush 16, and FIG. 5 is an explanatory diagram of a contact state between the commutator 14 and the brush tips 16a and 16b. Is shown. Hereinafter, the first embodiment of the present invention will be described with reference to FIGS.
A description will be given of a cylindrical micro vibration motor 1 as an embodiment.

Referring mainly to FIG. 1, a cylindrical micro-vibration motor 1 of the present invention has a cylindrical micro-vibration motor 2 having an outer diameter of 4 mm and a thickness of 0.2 m made of a magnetic material having the other end opened.
One end of the motor housing 3 having a cylindrical shape of about m is formed to have a thin outer diameter by protruding outwardly from the one end, thereby integrally forming the bearing house 5, and a shaft 10 is attached to one end in the bearing house 5. The bearing 4 is rotatably supported. From the direction of the other end of the motor housing 3,
A hollow stator yoke 8 is inserted, and a press-fit portion 17 having a narrow upper end portion is press-fitted into a lower end portion of the bearing house 5.

The length of the press-fit portion 17 is
, The bearing 4 such as the sleeve bearing can be accommodated in the upper part of the bearing house 5.

The main body of the cylindrical micro-vibration motor 1 is constructed by mounting a brush holder 14 constituting an end cap in which the lower end of the motor housing 7 is formed of resin or the like.

As described above, the hollow stator yoke 8 is inserted from the other end of the motor housing 3, and the press-fit portion 17 having a narrow upper end is pressed into the lower end of the bearing house 5. Since the protrusion 6 is formed at the upper end of the yoke 8, the bearing house at the upper end of the press-fit portion 17 of the stator yoke 8 is located at a position where the upper end of the protrusion 6 is in contact with the upper end surface of the motor housing 3. 5 is regulated.

The cylindrical field magnet 9 is positioned on the outer periphery of the stator yoke 8 until it comes into contact with the lower end of the projection 6. In this state, a field is applied to the outer periphery of the stator yoke 8 by using an adhesive or the like. The magnet 9 is fixed.

As a result, the field magnet 9 is arranged and fixed concentrically with the motor housing 3. The field magnet 9 is a two-pole magnet having N and S poles in the circumferential direction. In order to generate a sufficiently large torque in the cylindrical micro vibration motor 1 having a small diameter, the magnetic force is increased. It is formed using a strong magnet such as neodymium, boron or iron.

A cylindrical coreless armature 18 constituting a rotor is interposed in a radial gap between the motor housing 7 and the field magnet 9, and the shaft 10 provided on the coreless armature 18 holds the bearing 4 at that position. And brush holder 1
4 is rotatably supported by a center through hole provided in the base member 4. In this embodiment, the cylindrical coreless armature 18 has a known turtle-shaped winding, and an adhesive tape (not shown) is wound around the center of the outer periphery. However, another winding method may be used.

The lower end (the other end) of the cylindrical coreless armature 18 is fixed to the outer periphery of the commutator hub 19 by using an adhesive or the like. The commutator hub 19 is formed of a resin, and has a commutator 15 formed of a group of commutator pieces on an outer periphery of a lower end portion thereof.

The commutator hub 19 electrically connects the commutator pieces of the commutator 15 to the armature 18. Commutator 15
, A brush 15 provided on a brush holder 14 is slidably contacted to rectify the energized armature 18.

The center of the lower end of the vibration generating eccentric weight 11 is formed in a concave portion 13 serving as a concave portion, and the vibration generating eccentric weight 11 is made of a high specific gravity metal such as an inverted L-shaped tungsten alloy. Between the part 13 and one end of the motor housing 3 via the liner 21 the shaft 10
The eccentric weight 11 for generating an inverted L-shaped vibration is attached to
An extended bent piece 12 obtained by extending and bending an outer peripheral portion of a lower end of the eccentric weight 11 in a lower end direction is opposed to an outer peripheral portion of the bearing house 5.

According to the extension bending piece 12, the cylindrical micromotor 2 can be formed to be longer than the cylindrical micro vibration motor 1 'by about the length of the extension bending piece 12, so that the cylindrical micromotor 2 can be formed as before. Thus, a cylindrical micro-vibration motor 1 capable of obtaining a larger vibration can be obtained even if it is designed to have a length.

Next, the brush holder 14 and the commutator 15 will be described with reference to FIGS.

FIG. 2 is a view of the brush holder 14 as viewed from the inner surface in the axial direction, and FIG. 3 is a side longitudinal sectional view of the brush holder 14 for holding a pair of U-shaped brushes 16-1 and 16-2. Part 2
Brush holder 14 in which 2-1 and 22-2 are formed of resin
And the brush holders 22-1 and 22-2.
Brushes 16-1 and 16-2 are held by the commutator 15
At its tip is in sliding contact. [See FIGS. 2 and 4]

An insertion hole for passing the shaft 10 is formed at the center of the brush holder 14, and the shaft 10 is passed through the insertion hole.

As shown in FIG. 2, the lead wire 23- led to the outside at a position symmetrical with respect to 180 degrees is provided on the brush holder 14.
In addition to providing through holes 25-1 and 25-2 for passing through the holes 23-1 and 23-2, the conductors 24-1 and 24-2 of the lead wires 23-1 and 23-2 are provided.
Small diameter through-holes 26-1 and 26-2 for passing 4-2 are formed, and the conducting wires 24-1 and 24-2 are implanted.

One end of a pair of brush holders 22-1 and 22-2 projecting from the inner surface of the brush holder 14 is
Each of the brushes 16-1 and 16-2 is supported so as to be in sliding contact with the commutator 15, and each of the brushes 16-1 and 16-2 has a good rectifying characteristic as shown in FIG. The brush tips 16-1 and 16-2 are axially 2
It is slid into contact with the commutator 15 by using one divided into stages.

The other end of each of the brushes 16-1 and 16-2 is provided with a forked piece 28- integrally formed of the same conductive material.
1, 28-2 are formed by extension, and the forked piece 24-
The coreless armature 18, the commutator 15, and the brush 22-1 are sandwiched between the conductive wires 25-1 and 25-2 passed through the slits 27-1 and 27-2 of 1,24-2.
Or 22-2 and the conductive wire 24-1 or 24-2 are electrically conductively connected.

After the lead wires 25-1 and 25-2 pass through the slits 27-1 and 27-2 of the forked pieces 28-1 and 28-2, the conductive material is connected by means such as soldering. Are electrically connected to the forked pieces 28-1 and 28-2.

[0042]

Second Embodiment In the above embodiment, the case of a cylindrical micro vibration motor as a first embodiment of the present invention using a wire system has been described. Here, a contact type cylindrical micro vibration motor is shown. The case of is shown.

The description of the common portions will be omitted, and only the different portions will be described. Therefore, the second embodiment will be described with reference to FIGS. 8 and 9.

In the case of the cylindrical micro-vibration motor of the second embodiment, since the connection method is the same as that of the above-mentioned wire method, the same reference numerals are used for the common parts, and duplicate explanations are omitted.

The brush holder 14 has through-holes 25-1 and 25-2 formed at 180-degree symmetrical positions penetrating in the axial direction of the same size as in the case of the wire type, and a protrusion having a diameter smaller than the diameter. 29-1, 29-2, and the through hole 25
The conductive terminals 30-1 and 30-2 having an outer diameter substantially coincident with the inner diameters of the through holes 25-1 and 25-2.
Into the brush holder 14 so that the protrusion 2
9-1 and 29-2 are formed to protrude.

At the other end of each of the brushes 16-1 and 16-2, a forked piece 31- integrally formed of a conductive material having a shape suitable for sandwiching the projections 29-1 and 29-2.
1, 31-2 is formed to be extended, and this forked piece 31-
The coreless armature 18, 31-2 sandwiches the protrusions 29-1, 29-2 and sandwiches the conductive contacts.
The commutator 15, the brush 16-1 or 16-2, and the conductive terminal conductor 30-1 or 30-2 are conductively connected.

The other ends of the conductive terminals 30-1 and 30-2 are formed with a large-diameter flange 32 so as not to come off from the other end of the brush holder 14, thereby facilitating electrical contact with an external power supply. I have to.

[0048]

According to the present invention, a large vibration can be obtained even with a very small cylindrical micromotor having a limited length.
In addition, since there is little shaft bending and a remarkable effect on quality improvement can be exerted, it is particularly effective for a size having an outer diameter of 3 to 4 mm.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a cylindrical micro vibration motor showing an embodiment of the present invention.

FIG. 2 is a drawing of a brush holder used in the motor, viewed from an inner surface.

FIG. 3 is a side longitudinal sectional view of the brush holder.

4 and 5 are diagrams showing a contact relationship between a commutator and a brush.

FIG. 6 is a view of a brush holder used in a motor according to a second embodiment of the present invention, viewed from an inner surface.

FIG. 7 is a side longitudinal sectional view of the brush holder.

8 and 9 are explanatory views of a conventional cylindrical micro vibration motor.

[Explanation of symbols and symbols]

 1, 1 ', 1' 'cylindrical micro vibration motor 2, 2', 2 '' cylindrical micro motor 3, 3 ', 3' 'motor housing 4 bearing 5, 5', 5 '' bearing house 6 protrusion 7 Shaft insertion hole 8, 8 'Stator yoke 8' 'Closing lid / stator yoke 8'a Bearing house 9 Field magnet 10, 10' Shaft 11 Eccentric weight for vibration generation 12 Extended salient pole piece 13 Dented portion 14 Brush holder 15 Commutator 16 Brush 16a, 16b Brush tip 17 Press-fit portion 18 Cylindrical coreless armature 19 Commutator hub 20 Sliding sliding member 21 Liner 22-1, 22-2 Brush holding part 23-1, 23-2 Re- Wire 24-1, 24-2 Conductor 25-1, 25-2, 26-1, 26-2 Through-hole 27-1, 27-2 Slit 28-1, 28-2 Crotch 29-1 and 29-2 projections 30-1 and 30-2 Shirubedenta - Terminal 31-1 bifurcated portion 32 flange

[Procedure amendment]

[Submission date] November 14, 1997

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] All figures

[Correction method] Added

[Correction contents]

FIG.

FIG. 2

FIG. 3

FIG. 4

FIG. 5

FIG. 7

FIG. 8

FIG. 9

FIG. 6

Claims (1)

[Claims] 1. A cylindrical micro-vibration motor (1) comprising: One end of the motor housing (3) of the cylindrical micromotor (2) is formed into a small-diameter pipe shape, and a bearing house (5) for accommodating the bearing (4) is integrally formed and protruded outward at one end. That you are. A bearing (4) is built into one end of the bearing house (5). A projection (6) for restricting axial movement of the bearing (4) is provided between the motor housing (5) and the field magnet (9), and has a shaft insertion hole (7) extending in the axial direction. It has a hollow stator yoke (8). The protrusion (6) of the stator yoke (8) is positioned between the other end surface of the bearing (4) and one end surface of a field magnet (9) fixed to the outer periphery of the stator yoke (8). (4) The axial movement of the field magnet (9) is restricted. The outer diameter of the shaft (10) protruding from one end of the bearing house (5) through the shaft insertion hole (7) is formed to be substantially the same as or smaller than the outer diameter of the motor housing (3). The eccentric weight (11) for generating vibration having an inverted L-shape in vertical section is attached. The vibration generating eccentric weight (4) is formed by extending and bending a part of a lower end portion of the eccentric weight (4) in the direction of the lower end portion. Part.