Vibration motor

Abstract

To improve durability of an elastic member so as to enhance reliability of a vibration motor.SOLUTION: A vibration motor 1A includes: a housing 10; a vibrator 50 stored in the housing 10 and reciprocating in the longitudinal direction in the housing 10; and a pair of elastic members 60 supporting the vibrator 50 so that it can reciprocate in the longitudinal direction in the housing 10. The elastic members 60 are each a metal plate including a first fixing portion 63 fixed to the vibrator 50 and a second fixing portion 64 fixed to the housing 10. The first fixing portion 63 and the second fixing portion 64 are bent in the same direction and face each other in the front-back direction. The first fixing portion 63 and the second fixing portion 64 have a pair of bent portions extending to the inside, and the pair of bent portions face each other in the vertical direction.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a vibration motor. [Background technology]

[0002] Nowadays, various electronic devices such as smartphones and tablet terminals are equipped with vibration motors. One example of a vibration motor equipped in an electronic device is described in Patent Document 1. The vibration motor described in Patent Document 1 is a linear vibration motor in which a vibrating body vibrates linearly. The vibrating body of the vibration motor described in Patent Document 1 is housed in a housing and is supported by an elastic member so as to be able to vibrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-176688 A Summary of the Invention [Problem to be solved by the invention]

[0004] In order to increase the reliability of the vibration motor, it is desirable to improve the durability of the elastic member. [Means for solving the problem]

[0005] A vibration motor according to an embodiment includes a housing, a vibrating body accommodated in the housing and reciprocating in a first direction inside the housing, and a pair of elastic members supporting the vibrating body so that the vibrating body can reciprocate in the first direction inside the housing. Each of the elastic members is a metal plate including a first fixed portion fixed to the vibrating body, a second fixed portion fixed to the housing, and an intermediate portion connecting the first fixed portion and the second fixed portion. The first fixed portion and the second fixed portion are bent in the same direction with respect to the intermediate portion and face each other in a second direction perpendicular to the first direction. At least one of the first fixed portion and the second fixed portion includes a pair of bent portions extending toward one side or the other side of the second direction, and the pair of bent portions face each other in a third direction perpendicular to the first direction and the second direction. Effect of the Invention

[0006] According to the present invention, a highly reliable vibration motor in which the durability of the elastic member is improved is realized. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view showing the appearance of a vibration motor. [Diagram 2] FIG. 2 is a perspective view showing the structure of the vibration motor. [Diagram 3] FIG. 3 is an exploded perspective view showing the structure of the vibration motor. [Figure 4] FIG. 4 is an exploded perspective view showing the structure of the housing. [Diagram 5] FIG. 5 is a plan view showing a state in which the vibrating body is supported by an elastic member. [Figure 6A] FIG. 6A is an enlarged perspective view of one of the elastic members. [Figure 6B] FIG. 6B is an enlarged perspective view showing another elastic member. [Figure 7] FIG. 7 is an enlarged cross-sectional view taken along line AA in FIG. [Figure 8] FIG. 8 is an enlarged cross-sectional view taken along line BB in FIG. [Figure 9] FIG. 9 is a plan view showing a modified example of the arrangement of the elastic members. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an example of an embodiment will be described in detail with reference to the drawings. In all drawings for describing the embodiment, the same or substantially the same configurations and elements are designated by the same reference numerals. In addition, as a rule, once a configuration or element has been described, it will not be described repeatedly.

[0009] <Vibration motor overview> Fig. 1 is a perspective view showing the appearance of a vibration motor 1A according to this embodiment, Fig. 2 is a perspective view showing the structure of the vibration motor 1A, and Fig. 3 is an exploded perspective view showing the structure of the vibration motor 1A.

[0010] The vibration motor 1A has a housing 10 that forms the outer shell of the motor. The housing 10 is a metal box having a substantially rectangular planar shape. The housing 10 contains components of the vibration motor 1A, such as a substrate 30, a coil 40, and a vibrating body 50.

[0011] The vibrating body 50, which is one of the components of the vibration motor 1A, reciprocates inside the housing 10. More specifically, the vibrating body 50 reciprocates inside the housing 10 in the long side direction (longitudinal direction) of the housing 10. From another perspective, the vibrating body 50 generates vibrations in the long side direction of the housing 10. In other words, the vibration motor 1A is a horizontally driven linear vibration motor that generates vibrations in the long side direction of the housing 10.

[0012] Here, the direction of the long side of the housing 10 is defined as the "left-right direction," and the direction of the short side of the housing 10 is defined as the "front-rear direction." Additionally, the direction perpendicular to both the left-right direction and the front-rear direction is defined as the "up-down direction." According to these definitions, the vibrating body 50 generates vibrations in the left-right direction.

[0013] From another perspective, the left-right direction is the direction of reciprocating motion of the vibrating body 50 and corresponds to the first direction of the present invention. The front-rear direction is one of the directions perpendicular to the left-right direction and corresponds to the second direction of the present invention. The up-down direction is a direction perpendicular to the front-rear direction and the left-right direction and corresponds to the third direction of the present invention.

[0014] <Case> 4 is an exploded perspective view showing the structure of the housing 10. The housing 10 has a top wall 11 and a bottom wall 12 that face each other in the up-down direction, a front wall 13 and a rear wall 14 that face each other in the front-rear direction, and a right wall 15 and a left wall 16 that face each other in the left-right direction. In other words, a vibrating body 50 that vibrates in the long side direction (left-right direction) of the housing 10 vibrates between the right wall 15 and the left wall 16 in the opposing direction. In the following description, the front wall 13, the rear wall 14, the right wall 15, and the left wall 16 may be collectively referred to as a "periphery wall 17."

[0015] The housing 10 is formed of sheet metal (e.g., stainless steel plate). However, the top wall 11, the bottom wall 12, and the peripheral wall 17 are formed of separate pieces of sheet metal. In other words, the housing 10 is formed of multiple integrated sheets of sheet metal.

[0016] The peripheral wall 17 is formed into a rectangular tube shape by a band-like metal plate whose both ends are fixed to each other. Both ends of the metal plate forming the peripheral wall 17 are located on the rear wall 14. More specifically, both ends of the metal plate forming the peripheral wall 17 are located at the longitudinal center (center in the vibration direction) of the rear wall 14. By arranging both ends of the metal plate fixed to each other on the rear wall 14, it is possible to improve the impact resistance of the vibration motor 1A.

[0017] For example, when the vibration motor 1A (housing 10) is subjected to an impact due to being dropped or the like, the vibrating body 50 is less likely to come into contact with both ends (fixing portions) of the metal plate forming the peripheral wall portion 17. Although both ends of the metal plate forming the peripheral wall portion 17 are fixed by caulking, they may be fixed by welding or other fixing methods.

[0018] The top wall 11 and the bottom wall 12 are each formed of a flat metal sheet punched into a substantially rectangular shape. The top wall 11 closes an opening on one end side of the peripheral wall 17, and the bottom wall 12 closes an opening on the other end side of the peripheral wall 17. The peripheral edge of the metal sheet forming the top wall 11 is welded to one end of the metal sheet forming the peripheral wall 17. In addition, the peripheral edge of the metal sheet forming the bottom wall 12 is welded to the other end of the metal sheet forming the peripheral wall 17.

[0019] A pair of restricting portions 11a, 11b are provided on the left and right sides of the top wall portion 11. The restricting portions 11a, 11b are located on the left and right sides of the vibrating body 50 and restrict the reciprocating motion of the vibrating body 50 within a predetermined range. From another perspective, the vibrating body 50 can vibrate between the restricting portions 11a and 11b.

[0020] However, in a normal vibration state, the vibrating body 50 does not come into contact with the restricting portion 11a or the restricting portion 11b. If the vibrating body 50 vibrates (moves) more than normal for some reason, the vibrating body 50 comes into contact with the restricting portion 11a or the restricting portion 11b. As a result, excessive vibration (movement) of the vibrating body 50 is prevented. Note that restricting portions similar to the restricting portions 11a and 11b may be provided on the bottom wall portion 12.

[0021] <Substrate> Referring again to Fig. 3, the substrate 30 is a flexible printed circuit board on which electrical wiring is formed for supplying power to the coil 40 shown in the figure. The substrate 30 is disposed on the bottom wall portion 12 of the housing 10. Most of the substrate 30 is disposed inside the housing 10, but a portion of the substrate 30 is extended to the outside of the housing 10.

[0022] In the following description, the majority of the board 30 arranged inside the housing 10 will be referred to as the "main body portion," and the portion of the board 30 that extends outside the housing 10 will be referred to as the "connection portion," to distinguish between the two.

[0023] The connection portion of the substrate 30 is provided with a connection terminal 33 that is electrically connected to an input end of the electrical wiring formed in the main body. The connection portion extends across one (left) short side of the housing 10 to the outside of the housing 10 (see Figs. 1 and 2). Specifically, the connection portion is pulled out to the left side of the housing 10 through between the bottom wall portion 12 and the left side wall portion 16 shown in Fig. 4. However, the pull-out direction of the connection portion can be changed as appropriate.

[0024] <Coil> The coil 40 shown in Figures 2 and 3 is formed by a conductive wire wound around a plate-shaped iron core. The coil 40 is connected to the output end of an electrical wiring formed in the main body of the substrate 30. Therefore, when a voltage is applied to the connection terminal 33 of the substrate 30, the voltage is applied to the coil 40 via the electrical wiring. Note that the coil 40 can also be replaced with an air-core coil.

[0025] <Vibration body> The vibrating body 50 includes a weight 51 and two magnet groups 52. The weight 51 is a block of a metal alloy (for example, a tungsten alloy). The weight 51 is surrounded by the peripheral wall portion 17 of the housing 10, and has a side surface 53 facing the peripheral wall portion 17. The weight 51 further has an upper surface 54 connected to one peripheral edge of the side surface 53, and a lower surface 55 connected to the other peripheral edge of the side surface 53.

[0026] A magnet housing portion 56 is formed in the center of weight 51, penetrating weight 51 in the vertical direction, and magnet groups 52 are housed in magnet housing portion 56. Each magnet group 52 includes three plate-shaped permanent magnets aligned in the left-right direction.

[0027] The two magnet groups 52 face each other with the coil 40 sandwiched between them in the magnet housing portion 56. A back yoke 57 is disposed behind each magnet group 52, and pole pieces 58 are disposed on both axial sides of the coil 40.

[0028] When a voltage is applied to coil 40 via electrical wiring provided on substrate 30, coil 40 is magnetized and generates magnetic flux. Then, due to magnetic interaction between the magnetic flux generated around coil 40 and the magnetic flux generated around magnet group 52, vibrating body 50 including weight 51 and magnet group 52 reciprocates (vibrates) in the left-right direction.

[0029] <Elastic material> The vibrating body 50 is supported so as to be capable of reciprocating motion by a pair of elastic members 60. In the following description, the elastic member 60 disposed on one side (right side) of the vibrating body 50 in the left-right direction may be referred to as the "elastic member 61," and the elastic member 60 disposed on the other side (left side) of the vibrating body 50 in the left-right direction may be referred to as the "elastic member 62." However, this distinction is merely made for the sake of convenience.

[0030] Fig. 5 is a plan view showing a state in which the vibrating body 50 is supported by the elastic members 60. Fig. 6A is an enlarged perspective view of the elastic member 61, and Fig. 6B is an enlarged perspective view of the elastic member 62.

[0031] The elastic member 60 is a metal plate having a thickness of 1.0 mm or less. From another perspective, the elastic member 60 is a leaf spring having a thickness of 1.0 mm or less. However, the thickness of the metal plate serving as the elastic member 60 is not limited to 1.0 mm or less. In addition, the material of the metal plate is not limited to a specific material.

[0032] A first fixed portion 63 is provided on one end side of the elastic member 60, and a second fixed portion 64 is provided on the other end side of the elastic member 60. In addition, the first fixed portion 63 and the second fixed portion 64 are connected via an intermediate portion 65.

[0033] However, the distinction between the first fixed portion 63, the second fixed portion 64, and the intermediate portion 65 is merely for the sake of convenience of explanation. In other words, the first fixed portion 63 is a part of a single metal plate, the second fixed portion 64 is another part of the single metal plate, and the intermediate portion 65 is yet another part of the single metal plate.

[0034] The first fixing portion 63 and the second fixing portion 64 are bent at a right angle or approximately a right angle in the same direction with respect to the intermediate portion 65, and face each other in the front-rear direction. As a result, the elastic member 60 has a substantially U-shaped planar shape.

[0035] The middle portion 65 of the elastic member 60 becomes gradually narrower from both outer sides toward the inside in the longitudinal direction. From another perspective, the vertical dimension (width) of the middle portion 65 becomes gradually narrower from both outer sides toward the inside in the longitudinal direction.

[0036] The first fixing portion 63 has a pair of bent portions 66a, 66b extending toward one side (front side) in the front-rear direction. The second fixing portion 64 has a pair of bent portions 67a, 67b extending toward the other side (rear side) in the front-rear direction.

[0037] From another perspective, the first fixing portion 63 includes a pair of bent portions 66a, 66b bent inward, and the second fixing portion 64 also includes a pair of bent portions 67a, 67b bent inward.

[0038] The bent portions 66a and 66b of the first fixing portion 63 are bent inward by 90 degrees. As a result, the bent portions 66a and 66b face each other in the vertical direction. Similarly, the bent portions 67a and 67b of the second fixing portion 64 are bent inward by 90 degrees. As a result, the bent portions 67a and 67b face each other in the vertical direction.

[0039] As described above, the elastic members 61 and 62 have the same shape and structure. Furthermore, the elastic members 61 and 62 have in common that the first fixed portion 63 is fixed to the weight 51 of the vibrating body 50 and the second fixed portion 64 is fixed to the peripheral wall portion 17 of the housing 10.

[0040] However, the first fixed portion 63 of the elastic member 61 is welded to the right side of the weight 51, while the first fixed portion 63 of the elastic member 62 is welded to the left side of the weight 51. More specifically, the first fixed portion 63 of the elastic member 61 is welded to the right side of the rear surface of the weight 51, which faces the rear wall portion 14 of the housing 10. On the other hand, the first fixed portion 63 of the elastic member 62 is welded to the left side of the rear surface of the weight 51, which faces the rear wall portion 14 of the housing 10. In addition, the second fixed portion 64 of the elastic member 61 is welded to the right side of the inner surface of the front wall portion 13 of the housing 10, while the second fixed portion 64 of the elastic member 62 is welded to the left side of the inner surface of the front wall portion 13 of the housing 10.

[0041] 7 is an enlarged cross-sectional view taken along line AA in FIG. 5, and FIG. 8 is an enlarged cross-sectional view taken along line BB in FIG.

[0042] As shown in Fig. 7, a pair of bent portions 66a, 66b provided in the first fixed portion 63 of the elastic member 61 face each other in the vertical direction with the weight 51 between them. As shown in Fig. 8, a pair of bent portions 66a, 66b provided in the first fixed portion 63 of the elastic member 62 also face each other in the vertical direction with the weight 51 between them.

[0043] As described above, each first fixed portion 63 is fixed to weight 51 by welding. However, bent portions 66a, 66b which are part of first fixed portion 63 are not welded to weight 51. In other words, a portion of each first fixed portion 63 other than bent portions 66a, 66b (a portion facing the back surface of weight 51) is welded to weight 51.

[0044] Incidentally, a recess 59 that is one step lower than other portions is formed on the upper surface 54 and the lower surface 55 of the weight 51. The bent portion 66a is superimposed on the bottom surface of the recess 59 formed on the upper surface 54 of the weight 51, and the bent portion 66b is superimposed on the bottom surface of the recess 59 formed on the lower surface 55 of the weight 51.

[0045] As a result, the upper surface of bent portion 66a is flush or approximately flush with upper surface 54 of weight 51, and the lower surface of bent portion 66b is flush or approximately flush with lower surface 55 of weight 51. In other words, the thicknesses of bent portions 66a and 66b are absorbed by recess 59. As a result, the provision of bent portions 66a and 66b does not result in an increase in the vertical dimensions (height / thickness) of housing 10.

[0046] In this embodiment, a first fixing portion 63 of an elastic member 60 fixed to the vibrating body 50 is provided with bent portions 66a, 66b extending in a direction perpendicular to the vibration direction (left-right direction) of the vibrating body 50. A second fixing portion 64 of the elastic member 60 fixed to the housing 10 is also provided with bent portions 67a, 67b extending in a direction perpendicular to the vibration direction (left-right direction) of the vibrating body 50.

[0047] As a result, stress occurring in the elastic member 60 due to movement of the vibrating body 50 is dispersed. More specifically, stress concentration on or near the base of the first fixed portion 63 and the second fixed portion 64 is suppressed. Therefore, even if the vibrating body 50 moves significantly more than usual, damage or deformation of the elastic member 60 is suppressed or prevented.

[0048] In other words, the elastic member 60 in this embodiment has superior durability to other elastic members that do not include the bent portions 66a, 66b and the bent portions 67a, 67b. As a result, there is no need to improve the durability of the elastic member 60 by using a reinforcing member, a restricting member, or the like, and the number of parts and the number of assembly steps can be reduced.

[0049] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit and scope of the present invention. For example, if a bent portion is provided in at least one of the first fixing portion 63 and the second fixing portion 64, the stress generated in the elastic member 60 is dispersed, and damage or deformation of the elastic member 60 can be suppressed or prevented.

[0050] From another perspective, either one of the bent portions 66a, 66b or the bent portions 67a, 67b may be omitted. However, from the viewpoint of more reliably suppressing or preventing damage or deformation of the elastic member 60, it is preferable to provide a bent portion in the first fixed portion 63 fixed to the vibrating body 50. In addition, it is preferable to provide a reinforcing plate in the second fixed portion 64 from which a bent portion is omitted.

[0051] The bent portions 66a, 66b and the bent portions 67a, 67b may extend in the opposite direction to that in the above embodiment. For example, the bent portions 66a, 66b may extend toward the rear side, and the bent portions 66a, 66b may extend toward the front side.

[0052] In addition, the bending angles of the bending portions 66a, 66b and the bending portions 67a, 67b are not limited to 90 degrees. They may be greater than 90 degrees or less than 90 degrees. By not limiting the bending angles of the bending portions 66a, 66b and the bending portions 67a, 67b to 90 degrees, the required accuracy of the bending process is lowered, which may facilitate processing and assembly.

[0053] In addition, the bending angle of the bent portions 66a, 66b and the bending angle of the bent portions 67a, 67b may be the same or different. For example, the bending angle of one of the bent portions 66a, 66b and the bent portions 67a, 67b may be 90 degrees or more, and the bending angle of the other may be less than 90 degrees.

[0054] However, by bending the bent portions 66a, 66b and the bent portions 67a, 67b inward by 90 degrees, it is possible to prevent the housing 10 from becoming large, and therefore the vibration motor 1A from becoming large. On the other hand, if the bending angle of the bent portions 66a, 66b is set to less than 90 degrees, it becomes easier to arrange the weight 51 between the bent portions 66a, 66b, and the workability of assembly can be improved.

[0055] Either one of the elastic members 61, 62 may be reversed. Fig. 9 is a plan view showing a modified arrangement of the elastic members 61, 62. The elastic member 61 shown in Fig. 9 is rotated 180 degrees with respect to the elastic member 61 shown in Fig. 5. In this case, the first fixing portion 63 of the elastic member 61 is welded to the right side of the front surface of the weight 51 facing the front wall portion 13 of the housing 10, and the second fixing portion 64 is welded to the right side of the inner surface of the rear wall portion 14 of the housing 10.

[0056] The present invention can have the following configurations.

[0057] (1) A housing and a vibrator housed in the housing and reciprocating in a first direction inside the housing; a pair of elastic members supporting the vibrator so as to be capable of reciprocating in the first direction inside the housing; each of the elastic members is a metal plate including a first fixed portion fixed to the vibrating body, a second fixed portion fixed to the housing, and an intermediate portion connecting the first fixed portion and the second fixed portion; the first fixing portion and the second fixing portion are bent in the same direction with respect to the intermediate portion and are opposed to each other in a second direction perpendicular to the first direction, At least one of the first fixed portion and the second fixed portion includes a pair of bent portions extending toward one side or the other side in the second direction, The pair of bent portions face each other in a third direction perpendicular to the first direction and the second direction.

[0058] (2) the first fixing portion and the second fixing portion each include a pair of the bent portions, The vibration motor according to (1), wherein the pair of bent portions of the first fixed portion face each other with the vibrating body interposed therebetween.

[0059] (3) The vibration motor according to (1) or (2), wherein one of the elastic members is arranged on one side of the vibrating body in the first direction, and the other of the elastic members is arranged on the other side of the vibrating body in the first direction.

[0060] (4) Each of the first fixing portions is welded to a weight of the vibrating body, The vibration motor according to any one of (1) to (3), wherein each of the second fixed portions is welded to the housing.

[0061] (5) Each of the second fixing portions is welded to a peripheral wall portion of the housing that surrounds the weight, Each of the first fixing portions is welded to a side surface of the weight that faces the peripheral wall portion of the housing, One of the bent portions of each of the first fixing portions overlaps with a lower surface of the weight that is connected to the side surface of the weight, The vibration motor according to (4), wherein the other bent portion of each of the first fixed portions overlaps an upper surface of the weight that is connected to the side surface of the weight. [Explanation of symbols]

[0062] DESCRIPTION OF THE PREFERRED EMBODIMENTS 1A... vibration motor, 10... housing, 11... top wall portion, 11a, 11b... restricting portion, 12... bottom wall portion, 13... front wall portion, 14... rear wall portion, 15... right side wall portion, 16... left side wall portion, 17... peripheral wall portion, 30... substrate, 33... connection terminal, 40... coil, 50... vibrating body, 51... weight, 52... magnet group, 53... side surface, 54... upper surface, 55... lower surface, 56... magnet storage portion, 57... back yoke, 58... pole piece, 59... recess, 60, 61, 62... elastic member, 63... first fixed portion, 64... second fixed portion, 65... middle portion, 66a, 66b, 67a, 67b... bent portion

Claims

1. A housing and A vibrator that is accommodated in the housing and reciprocates in a first direction inside the housing; a pair of elastic members supporting the vibrator so as to be capable of reciprocating in the first direction inside the housing; each of the elastic members is a metal plate including a first fixed portion fixed to the vibrating body, a second fixed portion fixed to the housing, and an intermediate portion connecting the first fixed portion and the second fixed portion; the first fixing portion and the second fixing portion are bent in the same direction with respect to the intermediate portion and opposed to each other in a second direction perpendicular to the first direction, At least one of the first fixing portion and the second fixing portion includes a pair of bent portions extending toward one side or the other side in the second direction, A vibration motor, wherein the pair of bent portions face each other in a third direction perpendicular to the first direction and the second direction.

2. the first fixing portion and the second fixing portion each include a pair of the bent portions, The vibration motor according to claim 1 , wherein the pair of bent portions of the first fixed portion face each other with the vibrating body interposed therebetween.

3. The vibration motor according to claim 1 , wherein one of the elastic members is disposed on one side of the vibrating body in the first direction, and the other of the elastic members is disposed on the other side of the vibrating body in the first direction.

4. Each of the first fixing portions is welded to a weight provided on the vibrating body, The vibration motor according to claim 3 , wherein each of the second fixed portions is welded to the housing.

5. Each of the second fixing portions is welded to a peripheral wall portion of the housing that surrounds the weight, Each of the first fixing portions is welded to a side surface of the weight that faces the peripheral wall portion of the housing, One of the bent portions of each of the first fixing portions overlaps a lower surface of the weight that is connected to the side surface of the weight, The vibration motor according to claim 4 , wherein the other of the bent portions of each of the first fixed portions overlaps an upper surface of the weight that is connected to the side surface of the weight.

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