WO2006022010A1

WO2006022010A1 - Eccentric weight, method of producing the same, vibration motor, and portable apparatus

Info

Publication number: WO2006022010A1
Application number: PCT/JP2004/012291
Authority: WO
Inventors: Kenichi Shimodaira; Takaomi Tanaka; Yoshito Hirata; Hidehiko Ichikawa; Akira Shimojima; Hikaru Yoshizawa; Kenichi Kusano
Original assignee: Nanshin Co., Ltd.
Priority date: 2004-08-26
Filing date: 2004-08-26
Publication date: 2006-03-02
Also published as: WO2006022354A1

Abstract

An eccentric weight (120) comprising a weight (140) that is made of a high specific gravity metal and a shaft body (130) that has a hole (134) for holding the weight (140) and a hole (132) for holding a motor shaft and is made of a material having a specific gravity lower than that of the high specific gravity metal, wherein the weight (140) is held in the weight holding hole (134) over the entire circumference. Since the weight (140) of the eccentric weight (120) is held in the weight holding hole (134), of the shaft body (130), over the entire circumference, reduction in reliability in the bonding between the weight and the shaft body is suppressed even when a vibration motor is used for a long time.

Description

Eccentric weight, manufacturing method thereof, vibration motor and portable device

TECHNICAL FIELD [0001] The present invention relates to an eccentric weight, a manufacturing method thereof, a vibration motor, and a portable device.

In mobile phones and PDAs, vibration motors are used to notify incoming calls by vibration. FIG. 12 is a diagram for explaining such a vibration motor and an eccentric weight used in such a vibration motor. Fig. 12 (a) is a perspective view of a vibration motor, Fig. 12 (b) is a cross-sectional view of an eccentric weight cut along a plane perpendicular to the motor shaft, and Fig. 12 (c) is an eccentric weight on the motor shaft. It is sectional drawing cut by the plane which followed. In FIGS. 12 (b) and 12 (c), the position of the eccentric weight in FIG. 12 (a) in the rotational direction is changed.

[0003] As shown in FIG. 12, the vibration motor 1100 includes a small cylindrical motor main body 1110 and an eccentric weight 1120 having a substantially fan shape and also having a force such as a sintered body of tandastane. The motor shaft 1112 of the motor body 1110 is passed through and held in the motor shaft holding hole 1122 of the eccentric weight 1120. Eccentric weight 1120 is the tip of the motor shaft 1112 with a caulking stop by deforming the motor shaft holding hole 1122 by deforming the motor shaft holding hole 1122 by measuring the side force of the thin direction force of the motor shaft holding hole 1122 that passes through the motor shaft 1112. (For example, see Patent Document 1).

[0004] By the way, for a mobile phone, a PDA, and the like, there is a demand for a vibration motor that can obtain a necessary amount of vibration with low power consumption and light weight. For this reason, another eccentric weight as shown in FIG. 13 has been proposed as an eccentric weight used in such a vibration motor. FIG. 13 is a diagram for explaining another conventional eccentric weight. Fig. 13 (a) is a front view, Fig. 13 (b) is an A-A cross-sectional view of Fig. 13 (a), Fig. 13 (c) is a front view of the component, and Fig. 13 (d ) Is a sectional view taken along line BB in FIG. 13 (c). In FIG. 13 (a) and FIG. 13 (b), a part of the motor body 1210 is also shown.

As shown in FIG. 13, another conventional eccentric weight 1220 includes a motor shaft 1 of a motor body 1210. A cylindrical shaft 1230 having a motor shaft holding hole 1232 for holding 212 and having a low specific gravity metal force, and a substantially half-pipe weight 1240 having a high specific gravity metal force (for example, Patent Document 1). (Refer to) o For this reason, since the weight 1240 also has a high specific gravity metal force, the center of gravity of the eccentric weight 1220 is disposed at a position where the center axial force of the motor shaft holding hole 1232 is also separated. As a result, the amount of eccentricity in the eccentric weight 1220 increases, and by using such other conventional eccentric weight 1220, a vibration motor that can obtain a required vibration amount with light weight and low power consumption can be configured. .

[0006] Patent Document 1: JP 2001-129479 A

Disclosure of the invention

Problems to be solved by the invention

However, in the other conventional eccentric weight 1220 described above, the weight 1240 is integrally joined and fixed to a part of the outer surface 1234 of the shaft body 1230 via the brazing portion 1250. When the motor is used for a long time, there is a problem that the reliability of the connection between the weight and the shaft is lowered.

[0008] Therefore, the present invention has been made to solve such problems, and is a vibration motor that can obtain a necessary amount of vibration with light weight, low V, and power consumption. The vibration motor can be used for a long time. It is an object of the present invention to provide an eccentric weight in which the reliability of the connection between the weight and the shaft body is suppressed even when used. It is another object of the present invention to provide a vibration motor and a portable device having such an excellent eccentric weight.

Means for solving the problem

(1) The eccentric weight of the present invention has a weight made of a high specific gravity metal key, a weight holding hole for holding the weight, and a motor shaft holding portion for holding the motor shaft, And a shaft body made of a material having a specific gravity lower than that of the high specific gravity metal constituting the weight, wherein the weight is held in the weight holding hole over the entire circumference.

For this reason, in the eccentric weight of the present invention, the weight is held in the weight holding hole in the shaft over the entire circumference. Therefore, according to the eccentric weight of the present invention, when the vibration motor is used for a long time, it is suppressed that the reliability of the connection between the weight and the shaft body is lowered.

[0011] Further, according to the eccentric weight of the present invention, the specific gravity is lower than the high specific gravity metal constituting the weight. Since the shaft body having material force is provided, the center of gravity of the eccentric weight is arranged at a position further away from the center axis of the motor shaft holding portion. For this reason, the amount of eccentricity in the eccentric weight increases, and by using such an eccentric weight, it becomes possible to configure a vibration motor that can obtain a large amount of vibration with light weight and low power consumption.

[0012] In the eccentric weight of the present invention, the entire circumference is the entire circumference of the weight in a plane perpendicular to the longitudinal direction of the weight, and the weight is not necessarily in the weight holding hole at both ends in the longitudinal direction of the weight. It does not have to be retained. Further, as will be described later, the weight does not necessarily have to be held in the weight holding hole in the shaft over the entire length of the weight.

(2) The eccentric weight of the present invention has a weight made of a high specific gravity metal key, a weight holding recess for holding the weight and a motor shaft holding portion for holding the motor shaft, And a shaft body made of a material having a specific gravity lower than that of the high specific gravity metal constituting the weight, wherein the weight is held in the weight holding recess for more than half a circumference.

[0014] For this reason, in the eccentric weight of the present invention, the weight is held in the weight holding recess in the shaft over a half circumference or more. Therefore, even with the eccentric weight of the present invention, it is possible to suppress a decrease in the reliability of the connection between the weight and the shaft body when the vibration motor is used for a long time.

[0015] Further, according to the eccentric weight of the present invention, since the shaft body having a material force having a specific gravity lower than that of the high specific gravity metal constituting the weight is provided, the center of gravity of the eccentric weight is the central axis of the motor shaft holding portion. It will be arranged in a position further separated. For this reason, the amount of eccentricity in the eccentric weight increases, and by using such an eccentric weight, it becomes possible to configure a vibration motor that can obtain a large amount of vibration with light weight and low power consumption.

[0016] In the eccentric weight of the present invention, the half or more means a half or more of the weight in a plane perpendicular to the longitudinal direction of the weight, and the weight is formed in the weight holding recess at both ends in the longitudinal direction of the weight. It is not necessarily held. Further, as will be described later, the weight does not necessarily need to be held in the weight holding recess in the shaft over the entire length of the weight.

[0017] In the eccentric weight of the present invention, a motor shaft holding portion for holding the motor shaft; The motor shaft holding hole for holding the motor shaft over the entire circumference and the motor shaft holding both the motor shaft, for example, also with a three-way force, and after inserting the motor shaft, both the motor shaft holding recess for joining by pressing the opening Including the case.

[0018] (3) In the eccentric weight described in (2) above, the width of the opening in the weight holding recess is preferably narrower than the maximum length parallel to the width direction of the opening in the weight.

With this configuration, the weight is more firmly held in the weight holding recess.

[0020] (4) In the eccentric weight described in (2) or (3) above, the maximum distance from the central axis of the motor shaft holding portion in the shaft body to the outer peripheral portion of the weight is in the shaft body. The central axial force of the motor shaft holding part is preferably larger than the maximum distance to the outer peripheral part of the shaft body.

With this configuration, the center of gravity of the eccentric weight is disposed at a position where the center axial force of the motor shaft holding portion is further away from the center of gravity of the shaft body. For this reason, the amount of eccentricity in the eccentric weight becomes large, and by using such an eccentric weight, it becomes possible to configure a vibration motor that can obtain a large amount of vibration with light weight and low power consumption.

[0022] (5) In the eccentric weight according to any one of (1) and (4) above, the material is preferably a metal having a specific gravity lower than that of the high specific gravity metal constituting the weight.

[0023] With this configuration, since the material having a specific gravity lower than that of the high specific gravity metal constituting the weight is a metal, the durability of the shaft body is improved and the shaft body and the weight are more firmly integrated. As a result, the reliability of the connection between the weight and the shaft can be further suppressed when the vibration motor is used for a long time.

(6) In the eccentric weight according to any one of the above (1) and (5), the material is preferably a stainless steel having a specific gravity lower than that of the high specific gravity metal constituting the weight. .

[0025] In general, a material constituting a weight (for example, tungsten, tungsten alloy, etc.) has a low corrosion resistance and tends to crack, so that the eccentric weight as a whole has a high corrosion resistance and is difficult to crack (for example, nickel. ). However, in such a case, the joint between the eccentric weight and the plating film and the plating film itself can easily crack. As a result, it becomes easy to generate creases due to such cracks. For this reason, there has been a problem that the reliability related to holding the motor shaft in the motor shaft holding portion decreases. On the other hand, stainless steel is originally a material with high corrosion resistance and resistance to cracking, so it is not necessary to apply a plating. For this reason, cracks do not occur at the joint between the eccentric weight and the plating film, and it is possible to suppress a decrease in reliability related to holding the motor shaft in the motor shaft holding portion.

[0026] In addition, there is a problem that a material (for example, tungsten, tungsten alloy, etc.) generally constituting a weight is fragile and easily cracked. On the other hand, since stainless steel is sticky, holding a brittle and fragile weight with stainless steel over the entire circumference or over a half circumference makes it easier for the material constituting the weight to break. Problems are also suppressed.

[0027] In addition, since materials (for example, tungsten and tungsten alloys) constituting weights are generally expensive, there has been a problem that it is not easy to reduce the manufacturing cost of eccentric weights. On the other hand, stainless steel is less expensive than tungsten and tungsten alloys, and so the cost of manufacturing eccentric weights can be reduced by using a relatively inexpensive stainless steel shaft. Become.

[0028] (7) In the eccentric weight according to any one of (1) and (6) above, the weight is selected from tandasten, tungsten alloy, osmium, osminium alloy, gold, gold alloy, iridium or iridium alloy. It is preferable to be powerful.

[0029] With this configuration, tungsten, tungsten alloy, osmium, osmium-um alloy, gold, gold alloy, iridium or iridium alloy has a very high specific gravity, so the center of gravity of the eccentric weight is the motor shaft holding part. It is arranged at a position further away from the central axis of the. For this reason, the amount of eccentricity in the eccentric weight is further increased. By using such an eccentric weight, it is possible to configure a vibration motor that can obtain a larger amount of vibration with light weight and less power consumption.

[0030] In the eccentric weight of the present invention, since the weight does not need a function for holding the motor shaft, the weight has a very simple shape (for example, a cross-section such as a circle, an ellipse, or a sector). Can be adopted. For this reason, as a weight, It is necessary to use a sintered body that has been sintered into the shape of a weight, or a sintered body that has the same cross-sectional shape as the cross-sectional shape of the weight (for example, a circle, an ellipse, a fan shape, etc.) that has been cut short. In addition, it is possible to use a weight obtained by cutting a sintered body made of a round bar into a cross-sectional shape that is the same as the cross-sectional shape of the weight. In addition, when the cross-sectional shape of the weight is a circle, it is possible to use a material obtained by cutting a sintered body having a round bar force as it is.

[0031] (8) In the eccentric weight according to any one of (1) and (7), the weight has a predetermined first plane including a central axis of the motor shaft holding portion as a symmetry plane. It is preferable to have a plane-symmetric shape.

[0032] With this configuration, the weight can be inserted into any end side force weight holding hole or weight holding recess, so that the weight is disposed in the weight holding hole or weight holding recess. The degree of freedom when doing so increases, and the workability improves. For this reason, the manufacturing cost at the time of manufacturing an eccentric weight can be made low.

[0033] In the eccentric weight of the present invention, the central axis of the motor shaft holding portion is the central axis of the motor shaft that is held by the motor shaft holding portion.

(9) In the eccentric weight described in (8), it is preferable that the weight has a plane-symmetric shape with a predetermined second plane orthogonal to the first plane as a plane of symmetry.

[0035] With this configuration, the weight can be inserted into the weight holding hole or the weight holding recess in any direction. Therefore, when placing the weight in the weight holding hole or the weight holding recess, The degree of freedom is further increased, and workability is further improved. For this reason, the manufacturing cost at the time of manufacturing an eccentric weight can be made still lower.

[0036] (10) In the eccentric weight according to any one of (1) and (9), the shaft body has a structure in which a plurality of thin plate members having a shape corresponding to the shaft body are stacked. I like it.

[0037] By configuring in this way, workability when placing a weight in the weight holding hole or weight holding recess of the shaft body is improved, and the manufacturing cost when manufacturing an eccentric weight is further reduced. Can do.

[0038] (11) The method for producing an eccentric weight of the present invention includes the eccentricity according to any one of (1) and (10) above. A method of manufacturing an eccentric weight for manufacturing a weight, comprising the step of caulking the shaft body in a state where the weight is inserted into the weight holding hole or the weight holding recess in the shaft body. Features.

[0039] Therefore, according to the eccentric weight manufacturing method of the present invention, the weight is held in the weight holding hole over the entire circumference, or is held in the weight holding recess over the half circumference. The weight is held firmly on the shaft. For this reason, when the vibration motor is used for a long time, it is further suppressed that the reliability of the connection between the weight and the shaft is lowered.

[0040] (12) An eccentric weight manufacturing method of the present invention is an eccentric weight manufacturing method for manufacturing an eccentric weight according to any one of (1) and (10) above, wherein the weight is It includes a step of press-fitting with a margin into the weight holding hole or the weight holding recess in the shaft body.

[0041] For this reason, the weight is also held in the weight holding hole over the entire circumference, or is held in the weight holding recess over the entire circumference by the eccentric weight manufacturing method of the present invention. The weight is firmly held by the shaft. For this reason, when the vibration motor is used for a long time, it is further suppressed that the reliability of the connection between the weight and the shaft is lowered.

[0042] (13) An eccentric weight manufacturing method of the present invention is an eccentric weight manufacturing method for manufacturing an eccentric weight according to any one of (1) and (10) above, The method includes a step of inserting the weight into the weight holding hole or the weight holding recess in the shaft while the temperature is higher than the temperature of the weight.

[0043] For this reason, also in the manufacturing method of the eccentric weight of the present invention, the weight is held in the weight holding hole over the entire circumference or is held in the weight holding recess over the half circumference. The weight is firmly held by the shaft. For this reason, when the vibration motor is used for a long time, it is further suppressed that the reliability of the connection between the weight and the shaft is lowered.

(14) An eccentric weight manufacturing method of the present invention is an eccentric weight manufacturing method for manufacturing an eccentric weight according to any one of (1) and (10) above, wherein the weight and the weight It includes a step of joining the shaft body.

[0045] For this reason, the weight is also held in the weight holding hole over the entire circumference, or is held in the weight holding portion over the entire circumference by the eccentric weight manufacturing method of the present invention. The weight is held firmly on the shaft. For this reason, when the vibration motor is used for a long time, it is further suppressed that the reliability of the connection between the weight and the shaft is lowered.

[0046] The step of joining the weight and the shaft can be performed by adhering the weight and the shaft, or by brazing the weight and the shaft. It can also be performed, or can be performed by welding the weight and the shaft.

[0047] Further, in the method for producing an eccentric weight of the present invention, the above-described steps can be used in combination. For example, an adhesive may be applied after crimping, an adhesive may be applied after brazing, spot welding may be performed after caulking, or brazing may be performed after spot welding.

(15) An eccentric weight manufacturing method of the present invention is an eccentric weight manufacturing method for manufacturing an eccentric weight according to any one of (1) and (9) above, The method includes the step of inserting the material of the shaft into the mold in a state where a part or all of the mold is put in a predetermined mold.

[0049] For this reason, the weight is also held in the weight holding hole over the entire circumference, or is held in the weight holding portion over the entire circumference by the eccentric weight manufacturing method of the present invention. The weight is held firmly on the shaft. For this reason, when the vibration motor is used for a long time, it is further suppressed that the reliability of the connection between the weight and the shaft is lowered.

[0050] (16) A vibration motor according to the present invention includes a motor body and the eccentric weight according to any one of (1) and (10) above.

[0051] Therefore, according to the vibration motor of the present invention, as described above, when the vibration motor is used for a long period of time, it is possible to suppress a decrease in the reliability of the connection between the weight and the shaft body. Since it has an eccentric weight, it becomes a vibration motor with high reliability for a long time.

[0052] (17) A portable device of the present invention includes the vibration motor according to (16).

[0053] For this reason, according to the portable device of the present invention, since the long-time reliable vibration motor is provided, the portable device is highly reliable for a long time.

Brief Description of Drawings

[FIG. 1] A view for explaining an eccentric weight according to the first embodiment. FIG. 2 is a view for explaining the vibration motor according to the first embodiment.

FIG. 3 is a view for explaining an eccentric weight according to the second embodiment.

FIG. 4 is a view for explaining an eccentric weight according to a third embodiment.

FIG. 5 is a view for explaining an eccentric weight according to a fourth embodiment.

FIG. 6 is a view for explaining a weight used for the eccentric weight according to the embodiment 1-4.

FIG. 7 is a view for explaining an eccentric weight according to the fifth embodiment.

FIG. 8 is a view for explaining an eccentric weight according to the sixth embodiment.

FIG. 9 is a view for explaining an eccentric weight according to the seventh embodiment.

FIG. 10 is a view for explaining an eccentric weight according to an eighth embodiment.

FIG. 11 is a view for explaining an eccentric weight according to the ninth embodiment.

FIG. 12 is a view for explaining a conventional vibration motor and an eccentric weight.

FIG. 13 is a view for explaining another conventional eccentric weight.

BEST MODE FOR CARRYING OUT THE INVENTION

[0055] Hereinafter, an eccentric weight, a manufacturing method thereof, a vibration motor, and a portable device of the present invention will be described based on the embodiments shown in the drawings.

[Embodiment 1]

FIG. 1 is a view for explaining an eccentric weight according to the first embodiment. Fig. 1 (a) is a view of the eccentric weight according to Embodiment 1 from the front, and Fig. 1 (b) is a view of the eccentric weight according to Embodiment 1 from the side. FIG. 1 is a perspective view of an eccentric weight according to the first embodiment, and FIG. 1 (d) is a perspective view of the eccentric weight according to the first embodiment viewed from an angle different from that in FIG. 1 (c).

As shown in FIG. 1, the eccentric weight 120 according to the first embodiment includes a weight 140 and a shaft body 130. Weight 140 has high specific gravity metal power. The shaft body 130 has a weight holding hole 134 for holding the weight 140 and a motor shaft holding hole 1 32 for holding the motor shaft 112 (see FIG. 2). However, the material strength is low. In the eccentric weight 120 according to the first embodiment, the weight 140 is held in the weight holding hole 1 34 over the entire circumference.

[0058] For this reason, according to the eccentric weight 120 according to the first embodiment, the weight 140 has a shaft extending over the entire circumference. Since the weight 130 is held in the weight holding hole 134 in the body 130, it is possible to suppress a decrease in the reliability of the connection between the weight 140 and the shaft body 130 when the vibration motor is used for a long time.

In addition, according to the eccentric weight 120 according to the first embodiment, since the shaft body 130 having a material force having a specific gravity lower than that of the high specific gravity metal constituting the weight 140 is provided, the center of gravity of the eccentric weight 120 is Therefore, it is arranged at a position further away from the central axis of the data shaft holding hole 132. For this reason, the amount of eccentricity in the eccentric weight 120 becomes large. By using such an eccentric weight 120, it is possible to construct a vibration motor that can obtain a large amount of vibration with light weight and low power consumption. Become.

[0060] Here, "the entire circumference" is the entire circumference of the weight 140 in a plane perpendicular to the longitudinal direction of the weight 140, and as shown in FIG. 1, at both ends of the weight 140 in the longitudinal direction. Is not necessarily held in the weight holding hole. Further, as shown in FIG. 1, the weight 140 does not necessarily have to be held in the weight holding hole 134 in the shaft body 130 over the entire longitudinal direction of the weight 140.

Further, “the central axis of the motor shaft holding hole 132” is the central axis of the motor shaft 112 (see FIG. 2) that the motor shaft holding hole 132 holds.

In the eccentric weight 120 according to the first embodiment, the weight 140 is a tungsten alloy force, and the shaft body 130 is also a stainless steel force having a specific gravity lower than that of the tungsten alloy.

[0063] For this reason, the shaft body 130 is made of a metal (stainless steel) having a specific gravity lower than that of the high specific gravity metal (tungsten alloy) constituting the weight 140, so that the durability of the shaft body is improved and the shaft body and The weight can be more firmly integrated, and further reduction in the reliability of the connection between the weight and the shaft when the vibration motor is used for a long time is further suppressed.

[0064] Further, since stainless steel is originally a material with high corrosion resistance and resistance to rustling, even if it is used as a shaft, it is not necessary to apply a plating. As a result, the joint between the shaft body and the plating film and the plating film itself are not cracked, and no cracks are generated due to the crack, and the motor shaft in the motor shaft holding hole is not cracked. Decrease in reliability regarding retention is suppressed.

[0065] Since stainless steel is sticky, it is brittle and easily cracked like a tungsten alloy! / Min By holding copper all over the circumference with sticky stainless steel, the problem of the weight being prone to cracking is also suppressed.

[0066] Further, since stainless steel is less expensive than tungsten alloy and the like, it is easy to lower the manufacturing cost of the eccentric weight by configuring the shaft body 130 with such relatively inexpensive stainless steel. Become.

[0067] As a manufacturing method of the weight 140, a manufacturing method in which a weight is obtained by sintering a tandasten alloy into a weight shape having a relatively complicated shape can be adopted. However, the eccentricity according to the first embodiment is used. For the weight 120, it is possible to employ a manufacturing method in which a tungsten alloy is sintered to form a round bar having a simple shape, and the round bar is cut out to obtain a weight. By doing so, the amount of the additive (for example, copper) contained in the tungsten alloy can be reduced, so that the specific gravity can be increased and the amount of eccentricity in the eccentric weight can be further increased. It ’s like this.

[0068] The eccentric weight 120 according to the first embodiment can be manufactured, for example, by the following method.

(1) A tungsten alloy round bar having a cross section larger than that of the weight 140 is prepared.

(2) Next, the outer periphery of the round bar is cut to produce a bar having a cross-sectional shape corresponding to the cross-sectional shape of the weight 140.

(3) Next, a weight having an outer shape corresponding to the weight 140 is manufactured by cutting the bar material to a predetermined length.

[0070] (4) A shaft body having an outer shape corresponding to the shaft body 130 is prepared separately from the above-described weight, and the shaft is inserted in the weight holding hole in the shaft body. By holding the body outward, the weight is held on the shaft.

(5) Thereby, the eccentric weight 120 in which the weight 140 is held in the weight holding hole 134 in the shaft body 130 over the entire circumference is manufactured.

[0071] By adopting such a method, the weight 140 is held by the weight holding hole 134 in the shaft body 130 over the entire circumference, so that the vibration motor is used for a long time. In addition, it is possible to suppress a decrease in the reliability of the connection between the weight and the shaft.

FIG. 2 is a view for explaining the vibration motor according to the first embodiment. Figure 2 (a) is real FIG. 2B is a perspective view of the vibration motor according to Embodiment 1, FIG. 2B is a view of the eccentric weight as viewed from the front, and FIG. 8C is a view of the eccentric weight as viewed from the side.

The vibration motor 100 according to the first embodiment is a vibration motor including a motor body 110 and an eccentric weight 120. Then, as described above, the vibration motor 100 according to the first embodiment is an excellent eccentric weight in which the reliability of the connection between the weight and the shaft body is suppressed when the vibration motor is used for a long time. 120. For this reason, since the vibration motor 100 according to the first embodiment is a vibration motor including such an excellent eccentric weight 120, it becomes a vibration motor with high reliability for a long time.

Therefore, by using the excellent vibration motor 100 having high reliability for a long time as the vibration motor of the portable device in this way, the portable device can be made a portable device having high reliability for a long time.

[Embodiment 2]

FIG. 3 is a view for explaining the eccentric weight according to the second embodiment. Fig. 3 (a) is a diagram of the eccentric weight according to Embodiment 2 as viewed from the front, and Fig. 3 (b) is a diagram of the eccentric weight as viewed from the side.

As shown in FIG. 3, the eccentric weight 220 according to the second embodiment has an eccentric weight according to the first embodiment in which the shape of the weight 240 (and the shape of the weight holding hole 234 in the shaft body 230) is the same. Different from 120. That is, in the eccentric weight 220 according to the second embodiment, the weight 240 has a substantially fan shape.

As described above, the eccentric weight 220 according to the second embodiment is the case where the weight 240 (and the accompanying shape of the weight holding hole 234 in the shaft body 230) is the eccentric weight 120 according to the first embodiment. However, since the weight 240 is held in the weight holding hole 234 in the shaft body 230 over the entire circumference, the vibration motor is lengthened as in the case of the eccentric weight 120 according to the first embodiment. When used for a long time, it is possible to suppress a decrease in the reliability of the connection between the weight and the shaft.

[0077] In addition, in the eccentric weight 220 according to the second embodiment, the shaft 230 having a material force having a specific gravity lower than that of the high specific gravity metal constituting the weight 240 is provided as in the case of the eccentric weight 120 according to the first embodiment. Since the center of gravity of the eccentric weight 220 is from the center axis of the motor shaft holding hole 232 Furthermore, it will be arrange | positioned in the position spaced apart. For this reason, the amount of eccentricity in the eccentric weight 220 becomes large, and by using such an eccentric weight 220, it is possible to configure a vibration motor that can obtain a large amount of vibration with light weight and low power consumption.

In the eccentric weight 220 according to the second embodiment, since the weight 240 has a substantially fan shape, the distance between the motor shaft holding hole 232 and the weight holding hole 234 is a predetermined distance. As a result, it is possible to obtain an effect that the deterioration of the motor shaft holding characteristic and the weight holding characteristic due to the interference between the motor shaft holding hole 232 and the weight holding hole 234 can be minimized.

[Embodiment 3]

FIG. 4 is a view for explaining the eccentric weight according to the third embodiment. Fig. 4 (a) is a view of the eccentric weight according to Embodiment 3 as viewed from the front, and Fig. 4 (b) is a view of the eccentric weight as viewed from the side.

As shown in FIG. 4, the eccentric weight 320 according to the third embodiment has a weight 340 shape (and a shape of the weight holding hole 334 in the shaft body 330) according to the first or second embodiment. Different from eccentric weight 120, 220. In other words, in the eccentric weight 320 according to the third embodiment, the weight 340 has a long and hexagonal shape along the substantially circumferential direction of the eccentric weight 320.

As described above, the eccentric weight 320 according to the third embodiment has an eccentric weight 1 in which the shape of the weight 340 (and the shape of the weight holding hole 334 in the shaft 330) is the same as in the first or second embodiment. Unlike the case of 20, 220, since the weight 340 is held in the weight holding hole 334 in the shaft 330 over the entire circumference, it is different from the case of the eccentric weight 120, 220 according to the embodiment 1 or 2. Similarly, when the vibration motor is used for a long time, it is possible to suppress a decrease in the reliability of the connection between the weight and the shaft body.

In addition, in the eccentric weight 320 according to the third embodiment, as in the case of the eccentric weights 120 and 220 according to the first or second embodiment, the material having a specific gravity lower than that of the high specific gravity metal constituting the weight 340. Since the shaft body 330 having the force is provided, the center of gravity of the eccentric weight 320 is arranged at a position where the center axial force of the motor shaft holding hole 332 is further separated. For this reason, the amount of eccentricity in the eccentric weight 320 is increased, and by using such an eccentric weight 320, it is possible to configure a vibration motor that can obtain a large amount of vibration with low power consumption. Become.

[Embodiment 4]

FIG. 5 is a view for explaining the eccentric weight according to the fourth embodiment. FIG. 5 (a) is a view of the eccentric weight according to Embodiment 4 as viewed from the front, and FIG. 5 (b) is a view of the eccentric weight as viewed from the side.

As shown in FIG. 5, the eccentric weight 420 according to the fourth embodiment includes the number and shape of weights 440, 442, 442 (and the number of weight holding holes 434, 436, 436 in the shaft body 430). And the shape) are different from those of the eccentric weights 120, 220, 320 according to the first to third embodiments. That is, in the eccentric weight 420 according to the fourth embodiment, the weight is composed of three weights 440, 442, and 4 42, and these three weights 440, 442, and 442 all have a circular cross section, and 1 Two weights 440 and weight 440 / J, and two weights 442, 442 power.

As described above, the eccentric weight 420 according to the fourth embodiment includes the number and shape of the weights 440, 442, 442 (and the number and shape of the weight holding holes 434, 436, 436 in the shaft body 430 accordingly). Is different from the eccentric weights 120, 220, 320 according to Embodiment 1-3, but each weight 440 is the same as the eccentric weight 120, 220, 320 according to Embodiment 1-13. , 442, and 442 are held in the weight holding holes 434, 436, and 436 in the shaft body 430 over the entire circumference, so that the reliability of the weight-shaft joint can be maintained when the vibration motor is used for a long time. The decline in sex is suppressed.

[0086] Further, in the eccentric weight 420 according to the fourth embodiment, as in the case of the eccentric weights 120, 220, and 320 according to the first and third embodiments, the high weight heavy metal constituting the weights 440, 442, and 442 is used. Since the shaft body 430 having a low specific gravity and a material force is provided, the center of gravity of the eccentric weight 420 is arranged at a position further separated from the center axis of the motor shaft holding hole 432. For this reason, the amount of eccentricity in the eccentric weight 420 becomes large, and by using such an eccentric weight 420, it is possible to configure a vibration motor that can obtain a large amount of vibration with light weight and low power consumption.

Further, in the eccentric weight 420 according to the fourth embodiment, the weights 440, 442, and 442 are all circular in cross section, so that the weight can be easily manufactured and the manufacturing cost can be reduced.

FIG. 6 is a diagram for explaining a weight used for the eccentric weight according to the first to fourth embodiments. The 6 (a) is a cross-sectional view of the weight in Embodiment 1, FIG. 6 (b) is a cross-sectional view of the weight in Embodiment 2, and FIG. 6 (c) is a cross-sectional view of the weight in Embodiment 3. FIG. 6D is a sectional view of the weight in the fourth embodiment.

In the eccentric weights 120, 220, 320, and 420 according to Embodiments 1 and 4, as shown in FIG. 6, the weights of the weights 140, 240, 340, 440, and 442! It has a plane-symmetric shape with a predetermined first plane As including the axis as a plane of symmetry.

[0090] Therefore, in the eccentric weights 120, 220, 320, 420 according to Embodiment 1-14, the weights 140, 240, 340, 440, 442 are connected to either end (the end shown in FIG. 1 (b)). See S and S.)

1 2 Since the force can be inserted into the weight holding hole 134, 234, 334, 434, 436, the weight holding hole 134, 234, 334, 434, 436 has the weight 140, 240, 340, 440, 442 This increases the degree of freedom when placing the battery and improves workability. For this reason, the manufacturing cost at the time of manufacturing an eccentric weight can be made low.

[0091] In the eccentric weights 120, 320, and 420 according to the first, third, and fourth embodiments, any of the weights 140, 340, 440, and 442 has a predetermined first plane orthogonal to the predetermined first plane As described above. 2 It has a plane-symmetric shape with plane Bs as the plane of symmetry.

[0092] For this reason, in the eccentric weights 120, 320, and 420 according to the first, third, and fourth embodiments, the weights 140, 340, 440, and 442 are! The weight holding holes 134, 334, 434, and 436 in the direction of deviation. [Because it can also be inserted, the degree of freedom when placing the weights 140, 340, 440, 442 in the weight holding holes 134, 334, 434, 436 is further increased, and the workability is further improved. For this reason, the manufacturing cost at the time of manufacturing an eccentric weight can be made still lower.

[Embodiment 5]

FIG. 7 is a view for explaining the eccentric weight according to the fifth embodiment. FIG. 7 (a) is a diagram of the eccentric weight according to Embodiment 5 as viewed from the front, and FIG. 7 (b) is a diagram of the eccentric weight as viewed from the side.

As shown in FIG. 7, the eccentric weight 520 according to the fifth embodiment is different in the structure of the shaft body 530 from the eccentric weight 120 according to the first embodiment. That is, in the eccentric weight 520 according to the fifth embodiment, the shaft body 530 serves as a weight holding portion, and holds the weight over a half circumference instead of the weight holding hole 134 that holds the weight over the entire circumference. Has a weight retaining recess 534 The

This weight holding recess 534 has a shape such that a part of the weight holding hole 1 34 in the eccentric weight 120 according to the first embodiment is opened along the central axis of the motor shaft holding hole 132. Yes.

As described above, the eccentric weight 520 according to the fifth embodiment is different from the case of the eccentric weight 120 according to the first embodiment in the structure of the shaft body 530. The weight weight 540 is applied to the shaft body 530 over a half circumference. Since the weight is retained in the weight retaining recess 534, the reliability of the connection between the weight and the shaft is reduced when the vibration motor is used for a long time, as in the case of the eccentric weight 120 according to the first embodiment. Is suppressed.

In addition, in the eccentric weight 520 according to the fifth embodiment, as in the case of the eccentric weight 120 according to the first embodiment, the shaft body 530 having a material force having a specific gravity lower than that of the high specific gravity metal constituting the weight 540 is provided. Therefore, the center of gravity of the eccentric weight 520 is arranged at a position further away from the center axis of the motor shaft holding hole 532. For this reason, the amount of eccentricity in the eccentric weight 520 becomes large, and by using such an eccentric weight 520, it becomes possible to configure a vibration motor that can obtain a large amount of vibration with light weight and low power consumption.

[0098] Here, "half or more" means more than half of the weight 540 in a plane perpendicular to the longitudinal direction of the weight 540, and as shown in FIG. 7, both ends of the weight 540 in the longitudinal direction. The part does not necessarily have to be held by the weight holding part. Further, as shown in FIG. 7, the weight 540 does not necessarily have to be held by the weight holding portion 534 in the shaft body 530 over the entire longitudinal direction of the weight 540.

In the eccentric weight 520 according to the fifth embodiment, the width L of the opening in the weight holding recess 534 is set narrower than the maximum length L parallel to the width direction of the opening in the weight 540.

twenty one

The For this reason, according to the eccentric weight 520 according to the fifth embodiment, the weight 540 is further held in the weight holding recess 534 with a greater force.

[Embodiment 6]

FIG. 8 is a view for explaining the eccentric weight according to the sixth embodiment. FIG. 8 (a) is a view of the eccentric weight according to Embodiment 6 as viewed from the front, and FIG. 8 (b) is a view of the eccentric weight as viewed from the side. As shown in FIG. 8, the eccentric weight 620 according to the sixth embodiment is different from the eccentric weight 120 according to the first embodiment in the structure of the shaft body 630. That is, in the eccentric weight 620 according to the sixth embodiment, the shaft body 630 serves as a motor shaft holding portion that holds the motor shaft, instead of the motor shaft holding hole 132 that holds the motor shaft over the entire circumference. A motor shaft holding recess 632 for holding the shaft also in three-way force is provided. The motor shaft is joined to the shaft body 630 by inserting the motor shaft into the motor shaft holding recess 632 and then applying force to the opening.

As described above, the eccentric weight 620 according to the sixth embodiment is different from the case of the eccentric weight 120 according to the first embodiment in the structure of the shaft body 630. The weight weight 640 is provided in the shaft body 630 over the entire circumference. Since the weight is held in the weight holding hole 634, as in the case of the eccentric weight 120 according to the first embodiment, when the vibration motor is used for a long time, the reliability of the connection between the weight and the shaft body decreases. It is suppressed.

Further, in the eccentric weight 620 according to the sixth embodiment, as in the case of the eccentric weight 120 according to the first embodiment, the shaft body 630 having a material force having a specific gravity lower than that of the high specific gravity metal constituting the weight 640 is provided. Thus, the center of gravity of the eccentric weight 620 is arranged at a position further away from the center axial force of the motor shaft holding recess 632. For this reason, the amount of eccentricity in the eccentric weight 620 becomes large, and by using such an eccentric weight 620, a vibration motor that can obtain a large amount of vibration with light weight and low power consumption can be configured.

It should be noted that “the central axis of the motor shaft holding recess 632” is the central axis of the motor shaft that the motor shaft holding recess 632 holds.

[Embodiment 7]

FIG. 9 is a view for explaining the eccentric weight according to the seventh embodiment. FIG. 9 (a) is a view of the eccentric weight according to Embodiment 7 as viewed from the front, and FIG. 9 (b) is a view of the eccentric weight as viewed from the side.

As shown in FIG. 9 (b), the eccentric weight 720 according to the seventh embodiment is different from the eccentric weight 120 according to the first embodiment in the structure of the shaft body 730. That is, in the eccentric weight 720 according to the seventh embodiment, the shaft body 730 has a structure in which a plurality of thin plate members 731 having a shape corresponding to the shaft body 730 are stacked.

As described above, in the eccentric weight 720 according to the seventh embodiment, the structure of the shaft body 730 is related to the first embodiment. Since the weight 740 is held in the weight holding hole 734 in the shaft body 730 over the entire circumference, as in the case of the eccentric weight 120 according to the first embodiment, When the vibration motor is used for a long time, it is possible to suppress a decrease in the reliability of the connection between the weight and the shaft.

In addition, in the eccentric weight 720 according to the seventh embodiment, as in the case of the eccentric weight 120 according to the first embodiment, the shaft body 730 having a lower specific gravity than the high specific gravity metal constituting the weight 740 is provided. Therefore, the center of gravity of the eccentric weight 720 is arranged at a position further away from the center axis of the motor shaft holding hole 732. For this reason, the amount of eccentricity in the eccentric weight 720 becomes large, and by using such an eccentric weight 720, a vibration motor that can obtain a large amount of vibration with light weight and low power consumption can be configured.

Further, in the eccentric weight 720 according to the seventh embodiment, the shaft body 730 has a structure in which a plurality of thin plate members 731 having a shape corresponding to the shaft body 730 are stacked. The workability when the weight 740 is arranged in the weight holding hole 734 of the 730 is improved, and the manufacturing cost when the eccentric weight is manufactured can be further reduced.

[0110] The eccentric weight 720 according to Embodiment 7 can be manufactured, for example, by the following method.

(1) A tungsten alloy round bar having a cross section larger than that of the weight 740 is prepared.

(2) Next, the outer periphery of the round bar is cut to produce a bar having a cross-sectional shape corresponding to the cross-sectional shape of the weight 740.

(3) Next, a weight having an outer shape corresponding to the weight 740 is manufactured by cutting the above-described bar material into a predetermined length.

(4) Apart from the above-described weight, a plurality of thin plate members having an outer shape corresponding to the shaft body 730

(Thin plate member that finally becomes a shaft body 730 in the eccentric weight 720 by laminating) 731 is prepared, and the weight is inserted into the weight holding hole in each thin plate member 731 (i.e., In a state in which a plurality of thin plate members 731 are put on the weight), the plurality of thin plate members 731 are clamped from the outside to hold the weights in the laminated members 731 stacked.

(5) As a result, the weight 740 was held in the weight holding hole 734 of the shaft body 730 over the entire circumference. An eccentric weight 720 is produced.

[Embodiment 8]

FIG. 10 is a view for explaining the eccentric weight according to the eighth embodiment. Fig. 10 (a) is a front view of the eccentric weight according to Embodiment 8, Fig. 10 (b) is a CC sectional view of Fig. 10 (a), and Fig. 10 (c) is Embodiment 8. FIG. 10 (d) is a perspective view of the eccentric weight according to the eighth embodiment, and also shows an angular force different from that in FIG. 10 (c).

[0114] As shown in FIG. 10, the eccentric weight 820 according to the eighth embodiment has the number and shape of the weights 840, 840, 840 (and the shape of the shaft 830 accordingly) as the eccentric weight according to the first embodiment. Different from 120. That is, in the eccentric weight 820 according to the eighth embodiment, the number of weights 840, 840, and 840 is three, and each weight 840, the shaft 830 is held as a first cylindrical force. It is held by the central portion 842 and the shaft body 830, so that it becomes 844 forces at both ends which are two second cylindrical forces! Further, the shaft body 830ί has weight holding recesses 834, 834, 834 for holding three weights 840, 840, 840. The shaft body 830 is set slightly smaller than the shaft body 130.

[0115] As described above, the eccentric weight 820 according to the eighth embodiment has the same number and shape of the weights 840, 840, 840 (and the shape of the shaft body 830) as the eccentric weight 120 according to the first embodiment. Unlike the case, each weight 840 is held in the weight holding recess 834 in the shaft body 830 for more than half a circle, so that the vibration motor is lengthened as in the case of the eccentric weight 120 according to the first embodiment. When used for a long time, it is possible to suppress a decrease in the reliability of the connection between the weight and the shaft.

In addition, in the eccentric weight 820 according to the eighth embodiment, as in the case of the eccentric weight 120 according to the first embodiment, the shaft body 830 also has a material force having a specific gravity lower than that of the high specific gravity metal constituting each weight 840. Therefore, the center of gravity of the eccentric weight 820 is arranged at a position further away from the center axial force of the motor shaft holding hole 832. For this reason, the amount of eccentricity in the eccentric weight 820 increases, and by using such an eccentric weight 820, a vibration motor that can obtain a large amount of vibration with light weight and low power consumption can be configured.

[0117] In the eccentric weight 820 according to the eighth embodiment, the width of the opening in each weight holding recess 834 is set to be narrower than the maximum length parallel to the width direction of the opening in each weight 840. . For this reason, according to the eccentric weight 820 according to the eighth embodiment, each weight 840 is further held by each weight holding recess 834.

Further, as described above, in the eccentric weight 820 according to the eighth embodiment, the shaft body 830 is set to be somewhat smaller than the shaft body 130, so that the motor shaft holding hole 832 in the shaft body 830 Central axial force The maximum distance to the outer periphery of each weight 840 is set so that the central axial force of the motor shaft holding portion 832 in the shaft body 830 is also larger than the maximum distance to the outer periphery of the shaft body 830.

Therefore, according to the eccentric weight 820 according to the eighth embodiment, the center of gravity of the eccentric weight 820 is arranged at a position further away from the center axis of the motor shaft holding hole 832 than the center of gravity of the shaft body 830. It will be. For this reason, the amount of eccentricity in the eccentric weight 820 increases, and by using such an eccentric weight 820, it is possible to configure a vibration motor that can obtain a large amount of vibration with light weight and low power consumption.

[Embodiment 9]

FIG. 11 is a view for explaining the eccentric weight according to the ninth embodiment. FIG. 11 (a) is a diagram of the eccentric weight according to the ninth embodiment, in which the shaft before the integral weight is seen is also viewed from the front, and FIG. 10 (b) is the front view of the eccentric weight according to the ninth embodiment. FIG.

As shown in FIG. 11, the eccentric weight 920 according to the ninth embodiment is different from the eccentric weight 820 according to the eighth embodiment in the structure of the shaft body 930. That is, in the eccentric weight 920 according to the ninth embodiment, two notches 936 are formed between the three weight holding recesses 934, 934, 934 in the shaft body 930 !.

As described above, the eccentric weight 920 according to the ninth embodiment is different from the case of the eccentric weight 820 according to the eighth embodiment in the structure of the shaft body 930. Each weight 940 has a shaft body 930 over a half circumference. Therefore, when the vibration motor is used for a long time, the reliability of the connection between the weight and the shaft body is improved, as in the case of the eccentric weight 820 according to the eighth embodiment. Decrease is suppressed.

Further, in the eccentric weight 920 according to the ninth embodiment, similarly to the eccentric weight 820 according to the eighth embodiment, the shaft body 930 also has a material force having a specific gravity lower than that of the high specific gravity metal constituting each weight 940. The center of gravity of the eccentric weight 920 is the center axis of the motor shaft holding hole 932. The force will also be located at a further distance. For this reason, the amount of eccentricity in the eccentric weight 920 becomes large, and by using such an eccentric weight 920, a vibration motor that can obtain a large amount of vibration with light weight and low power consumption can be configured.

Further, in the eccentric weight 920 according to the ninth embodiment, as described above, two notches 936 are formed between the three weight holding recesses 934, 934, 934 in the shaft body 930. Therefore, after placing the three weights 940, 940, 940, the two notches 936, 936 are crushed by caulking the shaft body 930 with external force. It will be. As a result, each opening in the weight holding recess 934, 934, 934 becomes smaller, so that according to the eccentric weight 920 according to the ninth embodiment, each weight 940 is further held and held in each weight holding recess 934. Will come to be.

[0125] Although the eccentric weight, the manufacturing method thereof, the vibration motor, and the portable device of the present invention have been described based on the above embodiments, the present invention is not limited to each of the above embodiments. Without departing from the gist, the present invention can be carried out in various modes within the scope, and for example, the following modifications are possible.

(1) In the eccentric weights 120-920 of the above embodiments, the force using tungsten alloy as the weight is not limited to this. For example, tungsten, osmium, osmium alloy, gold, gold alloy, iridium, iridium alloy, and other metals having higher specific gravity than the shaft body can be used.

(2) In the eccentric weight 120-920 of each of the above embodiments, a sintered body made of a round bar is cut as a weight, and the cut body processed into the same cross-sectional shape as the weight is cut short. However, the present invention is not limited to this. For example, as a weight, a sintered body sintered in the shape of a weight, or a sintered body with a deformed bar force that has the same cross-sectional shape as a weight (for example, a circle, an ellipse, a fan, etc.) is cut short. Can be used. In addition, when the cross-sectional shape of the weight is a circle, for example, a sintered body having a round bar force can be used as it is cut short.

(3) The manufacturing method of the eccentric weight according to Embodiment 1 includes the step of pressing the shaft body 130 in a state where the weight 140 is inserted into the weight holding hole 1 34 of the shaft body 130 at a predetermined position. The present invention is not limited to this. For example, weight 140 is used to hold weight 140 in shaft body 1 The manufacturing method may include a step of press-fitting to 34 with a margin, and the weight 140 is inserted into the weight holding hole 134 in the shaft body 130 while the temperature of the shaft body 130 is higher than the temperature of the weight 140. The manufacturing method including the process to do may be sufficient. Further, the manufacturing method may include a step of joining the weight 140 and the shaft body 130 by brazing, bonding, or welding. Further, the manufacturing method may include a step of inserting the material of the shaft body 130 into the mold in a state where a part or all of the weight 140 is placed in a predetermined mold. Moreover, the manufacturing method which used the above-mentioned process together may be used. For example, a manufacturing method including a step of bonding after crimping, a manufacturing method including a step of bonding after cuffing, a manufacturing method including a step of spot welding after crimping, brazing after spot welding, etc. A manufacturing method including a process is also possible.

(4) The vibration motor of the present invention can also be suitably used for a remote control of a game machine, a pachinko operation unit, an electric toothbrush and the like suitably used for portable devices such as mobile phones and PDAs.

Claims

The scope of the claims

[1] High specific gravity metal weight,

A shaft having a weight holding hole for holding the weight and a motor shaft holding portion for holding the motor shaft, and having a specific gravity lower than that of the high specific gravity metal constituting the weight. ,

The eccentric weight is characterized in that the weight is held in the weight holding hole over the entire circumference.

[2] A high specific gravity metal weight,

A weight holding concave portion for holding the weight and a motor shaft holding portion for holding the motor shaft, and a shaft body made of a low specific gravity material rather than a high specific gravity metal constituting the weight,

The eccentric weight is characterized in that the weight is held in the weight holding recess for more than half a circumference.

[3] In the eccentric weight according to claim 2,

An eccentric weight, wherein the width of the opening in the weight holding recess is narrower than the maximum length parallel to the width direction of the opening in the weight.

[4] The eccentric weight according to claim 2 or 3, wherein the central axial force of the motor shaft holding portion in the shaft body and the maximum distance to the outer peripheral portion of the weight are the central axial force of the motor shaft holding portion in the shaft body. An eccentric weight characterized by being larger than the maximum distance to the outer periphery of the shaft body.

[5] The eccentric weight according to any one of claims 1 to 4,

An eccentric weight, characterized in that the material having a lower specific gravity than the high specific gravity metal constituting the weight is a metal.

[6] The eccentric weight according to any one of claims 1 to 5,

An eccentric weight characterized by having a specific gravity lower than that of the high specific gravity metal constituting the weight and made of stainless steel.

[7] In the eccentric weight according to any one of claims 1 to 6,

The weights are tungsten, tungsten alloy, osmium, osmium alloy, gold, An eccentric weight made of gold alloy, iridium or iridium alloy.

[8] In the eccentric weight according to any one of claims 1 to 7,

2. The eccentric weight according to claim 1, wherein the weight has a plane-symmetric shape with a predetermined first plane including the central axis of the motor shaft holding portion as a plane of symmetry.

[9] The eccentric weight according to claim 8,

The eccentric weight is characterized in that it has a plane-symmetric shape with a predetermined second plane orthogonal to the first plane as a plane of symmetry.

[10] The eccentric weight according to any one of claims 1 to 9,

The eccentric weight is characterized in that the shaft body has a structure in which a plurality of thin plate members having a shape corresponding to the shaft body are laminated.

[11] A method for manufacturing an eccentric weight for manufacturing an eccentric weight according to any one of claims 1 to 10, comprising:

The manufacturing method of the eccentric weight characterized by including the process which crimps the said shaft body in the state which inserted the said weight in the said weight holding hole or the said weight holding recessed part in the said shaft body.

[12] A method of manufacturing an eccentric weight for manufacturing an eccentric weight according to any one of claims 1 to 10,

The manufacturing method of the eccentric weight characterized by including the process which press-fits the said weight in the said weight holding hole or the said weight holding recessed part in the said shaft body with a margin.

[13] A method for producing an eccentric weight for producing an eccentric weight according to any one of claims 1 to 10, comprising:

A method for producing an eccentric weight, comprising the step of inserting the weight into the weight holding hole or the weight holding recess in the shaft in a state where the temperature of the shaft is higher than the temperature of the weight. .

[14] A method for producing an eccentric weight for producing an eccentric weight according to any one of claims 1 to 10, comprising:

The manufacturing method of the eccentric weight characterized by including the process of joining the said weight and the said shaft.

[15] A method for producing an eccentric weight for producing the eccentric weight according to any one of claims 1 to 9. Law,

A method for producing an eccentric weight, comprising a step of inserting a material of the shaft into the mold in a state where a part or all of the weight is put in a predetermined mold.

[16] A vibration motor comprising the motor main body and the eccentric weight according to any one of claims 1 to 10.

17. A portable device comprising the vibration motor according to claim 16.