Linear vibration motor

Abstract

The invention provides a linear vibration motor. This linear vibration motor is provided with: an actuator having a mover and a stator, the mover having a magnet and a back yoke; a housing that accommodates the actuator; and an elastic member that is fixed to the mover and the housing and that supports the mover so that the mover can vibrate with respect to the housing. The elastic member includes a pair of first extending portions extending in a first direction, a pair of second extending portions extending in a second direction, and a fixing portion connected to the first extending portions. The fixing portion is located between the pair of first extension portions and the pair of second extension portions and is provided at a position overlapping a central portion of the elastic member. The fixing portion is fixed to the back yoke at a plurality of fixing points. The plurality of fixing points are provided at positions symmetrical with respect to a first reference line that passes through the central portion and is parallel to the first direction, and at positions symmetrical with respect to a second reference line that passes through the central portion and is parallel to the second direction.

Description

Technical Field

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

[0002] Conventionally, there is known a linear vibration motor that is provided in a switch or the like operated by a user and generates vibration when the user operates the switch.

[0003] Patent Document 1 discloses a linear vibration motor in which an elastic support body for elastically supporting a mover is provided on an upper portion of a frame.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2022-88960

[0005] However, due to the connection between the elastic support body and the mover, stress is concentrated on a specific portion of the elastic support body during vibration, which may cause damage to the elastic support body. Summary of the Invention

[0006] A linear vibration motor according to one embodiment of the present invention comprises: an actuator having a mover and a stator, the mover having a magnet and a back yoke; a housing that houses the actuator; and an elastic member fixed to the mover and the housing, supporting the mover so that it can vibrate relative to the housing. The elastic member comprises: a pair of first extensions extending in a first direction intersecting the vibration direction of the mover; a pair of second extensions extending in a second direction intersecting the first and vibration directions; and a fixing portion connected to the first extensions. The fixing portion is located between the pair of first extensions and the pair of second extensions and is positioned overlapping with the center portion of the elastic member. The fixing portion is fixed to the back yoke at multiple fixing points. The multiple fixing points are located at positions symmetrical with respect to a first reference line passing through the center portion and parallel to the first direction, and at positions symmetrical with respect to a second reference line passing through the center portion and parallel to the second direction.

[0007] According to the present invention, it is possible to suppress the concentration of stress caused by vibration of the elastic member. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a perspective view of the appearance of a linear vibration motor according to an embodiment.

[0009] Figure 2 This is an exploded perspective view of the linear vibration motor.

[0010] Figure 3 It is a three-dimensional diagram of the shell.

[0011] Figure 4 is a top view of the elastic component.

[0012] Description of labels

[0013] 10: Linear vibration motor; 20: Housing; 30: Actuator; 31: Stator; 32: Mover; 40: Elastic component; 41: Frame; 42: Fixing portion; 44, 45, 46: Bending portion; 50: Flexible printed circuit board (FPC); 201: Bottom panel; 202, 203: First side wall; 204, 205: Second side wall; 206, 207: Connecting plate; 320: Back yoke; 321: Magnet; 322: Pole piece; 323: Counterweight; 410, 411: First extension; 410a, 411a: External Edge; 412, 413: second extension part; 412a, 413a: protrusion; 414: notch part; 421: main fixing part; 421a, 421b, 422a, 422b, 423a, 423b: end edges; 422, 423: connecting parts; C: central part; D1, D2: step parts; G1: first fixing point group; G2: second fixing point group; G3: third fixing point group; RL1: first reference line; RL2: second reference line; WP1, WP2, WP3, WP4, WP5, WP6: fixing points. DETAILED DESCRIPTION

[0014] <Implementation Method>

[0015] Hereinafter, a linear vibration motor according to an embodiment will be described in detail with reference to the drawings.

[0016] Linear vibration motors are, for example, installed in various user-operated switches. Examples of switches equipped with linear vibration motors include the switch panels for air conditioning systems and power window controls found in automobiles. When a user operates one of these switches, the linear vibration motor vibrates, causing the switch to vibrate. In other words, when a user operates the switch, the linear vibration motor provides feedback to the user through vibration.

[0017] Overall Structure

[0018] Figure 1 1 is a perspective view of the appearance of the linear vibration motor 10 according to the embodiment. Figure 2 2 is an exploded perspective view of the linear vibration motor 10 . The linear vibration motor 10 includes a housing 20 , an actuator 30 , and an elastic member 40 .

[0019] <Casing 20>

[0020] Figure 3 2 is a perspective view of the housing 20. The housing 20 is made of a metal material such as stainless steel (SUS). The housing 20 includes a bottom plate 201, first side wall plates 202 and 203, second side wall plates 204 and 205, and connecting plates 206 and 207.

[0021] The bottom panel 201 is rectangular or substantially rectangular with a pair of long sides and a pair of short sides. In the following description, the direction along the long sides of the bottom panel 201 is referred to as the X direction, and the direction intersecting (perpendicular to) the X direction and along the short sides of the bottom panel 201 is referred to as the Y direction. Furthermore, the direction intersecting (perpendicular to) the X and Y directions is referred to as the Z direction. The X direction is sometimes referred to as the first direction, and the Y direction is sometimes referred to as the second direction.

[0022] A double-sided adhesive tape 51 (see Figure 2 The linear vibration motor 10 is fixed to the operation switch by attaching the double-sided adhesive tape 51 to the operation switch.

[0023] The first side wall panels 202 and 203 and the second side wall panels 204 and 205 are connected to the respective sides of the bottom panel 201 at their ends (one end) on the - side in the Z direction. Specifically, the first side wall panel 202 is connected to one long side (the + side in the Y direction) of the bottom panel 201, and the first side wall panel 203 is connected to the other long side (the - side in the Y direction) of the bottom panel 201. In other words, the first side wall panels 202 and 203 extend along the X direction (the first direction).

[0024] The second side wall plate 204 is connected to one short side (X direction + side) of the bottom plate 201, and the second side wall plate 205 is connected to the other short side (X direction - side) of the bottom plate 201. That is, the second side wall plates 204 and 205 extend along the Y direction (second direction).

[0025] The length (height) of the first side wall panels 202 and 203 along the Z direction is shorter (lower) than the length (height) of the second side wall panels 204 and 205 along the Z direction. That is, the height of the first side wall panels 202 and 203 from the bottom panel 201 is lower than the height of the second side wall panels 204 and 205 from the bottom panel 201. In other words, the first side wall panels 202 and 203 are connected to the second side wall panel 204 by a step portion D1 on the positive side in the Z direction. Similarly, the first side wall panels 202 and 203 are connected to the second side wall panel 205 by a step portion D2 on the positive side in the Z direction. The step portions D1 and D2 have a size (length) of approximately 0.8 [mm] to 1.2 [mm] along the Z direction, and more preferably a size (length) of approximately 1 [mm].

[0026] An actuator 30, described later, is housed within a space S enclosed by the bottom panel 201, the first sidewall panels 202 and 203, and the second sidewall panels 204 and 205. Specifically, the housing 20 houses the actuator 30. An opening 204a is formed in the second sidewall panel 204, extending through the space S and the exterior of the housing 20. A flexible printed circuit board (FPC) 50, which supplies power to the actuator 30 through this opening 204a, is inserted from outside the housing 20 into the space S. The opening 204a can be increased in size within a range that maintains the strength of the second sidewall panel 204.

[0027] A protruding surface 201a is formed below the X-direction positive side edge of the bottom panel 201, i.e., the opening 204a formed in the second side wall 204, protruding toward the X-direction positive side relative to the X-direction positive side edge of the bottom panel 201. Therefore, the protruding surface 201a has a size along the X-direction corresponding to the X-direction size of the opening 204a. The FPC 50 is fixed to the upper surface (the Z-direction positive side surface) of the protruding surface 201a by bonding or the like. The opening 204a can be increased within a range that maintains the strength of the second side wall 204, thereby increasing the X-direction size of the protruding surface 201a and ensuring the area of ​​the protruding surface 201a. As a result, the fixing strength of the FPC 50 can be improved, thereby preventing the FPC 50 from peeling off.

[0028] The connecting plate 206 is formed at the end (the other end) on the positive side in the Z direction of the second side wall plate 204. The connecting plate 206 is a surface that intersects the Z direction, that is, parallel to the XY plane. The connecting plate 206 protrudes further toward the positive side in the X direction than the second side wall plate 204. In other words, the end on the negative side in the X direction of the connecting plate 206 is connected to the end on the positive side in the Z direction of the second side wall plate 204.

[0029] The connecting plate 207 is formed at the end (the other end) on the positive side in the Z direction of the second side wall plate 205. The connecting plate 207 is a surface that intersects the Z direction, that is, is parallel to the XY plane. The connecting plate 207 protrudes further toward the negative side in the X direction than the second side wall plate 205. In other words, the positive end of the connecting plate 207 in the X direction is connected to the positive end of the second side wall plate 205 in the Z direction.

[0030] The connecting plates 206 and 207 are connected to the elastic member 40 described later to support the elastic member 40. In this case, the connecting plates 206 and 207 are joined to the elastic member 40 by welding. That is, the elastic member 40 is fixed to the end portion (the other end) on the positive side in the Z direction of the second side wall plates 205 and 204.

[0031] The connecting plates 206 and 207 protrude in the X direction from the second side wall plates 204 and 205 to a size larger than the welding diameter of 0.8 mm and capable of avoiding excessive enlargement of the housing 20 in the X direction.

[0032] As described above, the Z-direction height of the first sidewall panels 202 and 203 is lower than that of the second sidewall panels 204 and 205. Therefore, the connecting panels 206 and 207 connected to the second sidewall panels 204 and 205 are provided on the Z-direction positive side relative to the first sidewall panels 202 and 203.

[0033] <Actuator 30>

[0034] Figure 2 The actuator 30 shown includes a stator 31 and a mover 32. The actuator 30 is housed in a space S of the housing 20 in a state where the actuator 30 is engaged with an elastic member 40 to be described later.

[0035] <Stator 31>

[0036] The stator 31 is fixed to the Z-direction positive side surface of the bottom plate 201 of the housing 20 by bonding or other means. The stator 31 is a cylindrical, air-core coil formed by winding an electric wire. The stator 31 is arranged so that the coil axis is aligned or approximately aligned with the Z-direction. The cylindrical stator 31 houses a magnet 321 and pole pieces 322, described later. The stator 31 is electrically connected to the FPC 50. This allows power to be supplied to the stator 31 from the outside.

[0037] <Motor 32>

[0038] The mover 32 has the following structure: when the stator 31 is energized, the mover 32 can move (vibrate) in the positive and negative directions in the Z direction relative to the stator 31. Specifically, the mover 32 has a back yoke 320, a magnet 321, a pole piece 322, and a counterweight 323. In the following description, the Z direction is sometimes referred to as the vibration direction of the mover 32. That is, the first direction, which is the X direction, is a direction intersecting the vibration direction, and the second direction, which is the Y direction, is a direction intersecting the first direction and the vibration direction.

[0039] <Back yoke 320>

[0040] The back yoke 320 is a flat plate-shaped component made of a magnetic material such as ferritic stainless steel. It has a rectangular shape with two long sides extending in the X direction and two short sides extending in the Y direction. A magnet 321 is fixed to the Z-side surface of the back yoke 320 by adhesive or other means.

[0041] <Magnet 321>

[0042] The magnet 321 is formed into a columnar shape having an axis along the Z direction. Figure 2 , a cylindrical magnet 321 is shown, but the magnet 321 may also be a prism. The end surface of the magnet 321 on the positive side in the Z direction is fixed to the surface on the negative side in the Z direction of the back yoke 320 by bonding or the like.

[0043] The diameter of the magnet 321 is smaller than the inner diameter of the cylindrical stator 31. Therefore, the magnet 321 is housed in the stator 31 so as to be vibrable in the Z direction.

[0044] <Pole piece 322>

[0045] The pole piece 322 is formed into a disk shape with an outer diameter smaller than that of the magnet 321. The pole piece 322 is fixed to the Z-side end surface of the magnet 321 by adhesive bonding or the like. Therefore, the pole piece 322 is housed within the stator 31 so as to vibrate along the Z direction along with the magnet 321. The pole piece 322 is not limited to a disk shape and may also be a polygonal plate.

[0046] <Counterweight 323>

[0047] The weight 323 is a prism having a rectangular bottom with long sides along the X direction and short sides along the Y direction. The weight 323 is fixed to the Z-side surface of the back yoke 320 by bonding or the like.

[0048] The counterweight 323 has a through-hole 324 formed therein, extending through the counterweight 323 in the Z direction. The through-hole 324 has a diameter larger than the outer diameter of the cylindrical stator 31. Therefore, the stator 31, magnet 321, and pole piece 322 are housed within the through-hole 324. In other words, the through-hole 324 serves as a storage area for the stator 31, magnet 321, and pole piece 322.

[0049] By housing the stator 31 in the through-hole 324, the counterweight 323, which is connected to the magnet 321 via the back yoke 320, can also vibrate in the Z direction relative to the stator 31. Since the stator 31 is fixed to the bottom plate 201, the back yoke 320, the magnet 321, the pole piece 322, and the counterweight 323 can vibrate in the Z direction relative to the housing 20 within the space S.

[0050] <Elastic member 40>

[0051] Figure 4 This is a top view of the elastic member 40. The elastic member 40 is made of a metal material such as stainless steel. The elastic member 40 is in the form of a plate parallel to the XY plane. As described above, the elastic member 40 is fixed to the housing 20. A film 52, such as a resin material, is provided on the surface of the elastic member 40 on the positive side in the Z direction.

[0052] The back yoke 320 is joined to the Z-direction-side surface of the elastic member 40 by welding or the like. Specifically, the mover 32, including the back yoke 320, is fixed to the elastic member 40. As described above, the mover 32 vibrates in the Z-direction relative to the housing 20. Therefore, it can be said that the elastic member 40, fixed to the housing 20, supports the mover 32 so that it can vibrate relative to the housing 20. The elastic member 40 deforms (vibrates) in response to the vibration of the mover 32.

[0053] In the following description, an imaginary line passing through the center portion C (the center point and its surroundings) of the elastic member 40 and parallel to the X direction is referred to as a first reference line RL1. Furthermore, an imaginary line passing through the center portion C (the center point and its surroundings) of the elastic member 40 and parallel to the Y direction is referred to as a second reference line RL2.

[0054] The elastic member 40 includes a frame portion 41 and a fixing portion 42. In the elastic member 40, the frame portion 41 and the fixing portion 42 are integrally formed.

[0055] The frame portion 41 is composed of a pair of first extension portions 410 and 411 extending along the X direction (first direction) and a pair of second extension portions 412 and 413 extending along the Y direction (second direction). The X-direction positive end of the first extension portion 410 is connected to the Y-direction positive end of the second extension portion 412. The X-direction negative end of the first extension portion 410 is connected to the Y-direction positive end of the second extension portion 413. The X-direction positive end of the first extension portion 411 is connected to the Y-direction negative end of the second extension portion 412. The X-direction negative end of the first extension portion 411 is connected to the Y-direction negative end of the second extension portion 413.

[0056] The length of the first extensions 410 and 411 along the X direction is equal to or substantially equal to the length of the first sidewall plates 202 and 203 of the housing 20 along the X direction. The length of the second extensions 412 and 413 along the Y direction is equal to or substantially equal to the length of the second sidewall plates 204 and 205 of the housing 20 along the Y direction.

[0057] The width of the first extension portions 410 and 411 along the Y direction is smaller than the width of the fixing portion 42 (described later) along the Y direction. Specifically, the width of the first extension portions 410 and 411 is, for example, 0.73 mm. However, the width of the first extension portions 410 and 411 is not limited to the above values ​​and may be larger depending on the size of the linear vibration motor, etc.

[0058] A protrusion 412a is formed at the X-direction positive end of the second extension portion 412, protruding toward the X-direction positive side relative to the X-direction positive ends of the first extension portions 410 and 411. Furthermore, a protrusion 413a is formed at the X-direction negative end of the second extension portion 413, protruding toward the X-direction negative side relative to the X-direction negative ends of the first extension portions 410 and 411. The length along the X-direction between the X-direction positive end of protrusion 412a and the X-direction negative end of protrusion 413a is equal to or substantially equal to the length along the X-direction between the X-direction positive end of connection plate 206 and the X-direction negative end of connection plate 207 of housing 20.

[0059] As described above, in the X direction, the lengths of the first extensions 410 and 411 are equal to or substantially equal to the lengths of the first sidewall plates 202 and 203. Therefore, when the elastic member 40 is disposed on the housing 20, the protrusions 412a and 413a are positioned on the connecting plates 206 and 207. The protrusions 412a and 413a are joined to the connecting plates 206 and 207 by welding or the like, thereby securing the elastic member 40 to the housing 20.

[0060] As described above, the protrusions 412a and 413a are formed on the second extensions 412 and 413, and the connecting plates 206 and 207 are formed on the second side wall plates 204 and 205. Therefore, it can be said that the elastic member 40 is fixed to the end portion (the other end) on the positive side in the Z direction of the second side wall plates 204 and 205 via the second extensions 412 and 413.

[0061] As described above, the connecting plates 206 and 207 protrude from the second sidewall plates 204 and 205 in the X-direction by a greater amount than the weld diameter. Therefore, the connection between the connecting plates 206 and 207 and the elastic member 40 is strengthened. Consequently, as will be described later, even if the elastic member 40 vibrates in the positive and negative directions in the Z-direction due to vibration of the mover 32, it is possible to prevent the elastic member 40 from falling off the housing 20.

[0062] Arc-shaped curved portions 44 are formed at the four corners of the frame portion 41, where the first extensions 410 and 411 connect to the second extensions 412 and 413. Specifically, the first extensions 410 and 411 connect to the second extensions 412 and 413 via the curved portions 44. Therefore, the positive and negative ends of the first extensions 410 and 411 in the X direction are not parallel to the X direction, and the positive and negative ends of the second extensions 412 and 413 in the Y direction are not parallel to the Y direction. Furthermore, the protrusions 412a and 413a of the second extensions 412 and 413 connect to the curved portion 44 via the arc-shaped curved portions 45.

[0063] The fixed portion 42 is formed between the first extension portion 410 and the first extension portion 411, and between the second extension portion 412 and the second extension portion 413. More specifically, the interior of the fixed portion 42 on the XY plane includes the central portion C of the elastic member 40. In other words, the fixed portion 42 is provided at a position overlapping with the central portion C of the elastic member 40. The fixed portion 42 is joined to the back yoke 320 of the mover 32 by welding or the like, details of which will be described later.

[0064] The length of the fixed portion 42 in the X direction is shorter than the length of the first extensions 410 and 411 in the X direction. Furthermore, the length (width) of the fixed portion 42 in the Y direction is smaller than the distance between the first extensions 410 and 411, and larger than the width of the first extensions 410 and 411 in the Y direction. In other words, the width of the first extensions 410 and 411 in the Y direction is smaller than the width of the fixed portion 42 in the Y direction. As described later, this prevents stress concentration in specific locations that could damage the elastic member 40 when the elastic member 40 vibrates together with the mover 32.

[0065] The fixing portion 42 is connected to the pair of first extension portions 410 and 411. Specifically, the fixing portion 42 includes a main fixing portion 421 and a pair of connecting portions 422 and 423. The main fixing portion 421 is formed into a rectangular shape centered on the center portion C and having long sides extending along the X direction. In other words, the main fixing portion 421 extends along the first direction. The shape of the main fixing portion 421 is not limited to a rectangle; it may also be a circle or an ellipse.

[0066] A pair of connecting portions 422 and 423 extend along the Y direction and connect the main fixing portion 421 and the pair of first extension portions 410 and 411, respectively. Specifically, the connecting portion 422 connects the Y direction positive side of the main fixing portion 421 and the first extension portion 410. The connecting portion 423 connects the Y direction negative side of the main fixing portion 421 and the first extension portion 411. Figure 4 As shown, the length of the connecting portions 422 and 423 along the X direction is shorter than the length of the main fixing portion 421 in the X direction.

[0067] The arc-shaped curved portion 46 is formed at the junction of the first extension portions 410 and 411 and the connecting portions 422 and 423. In other words, near the second reference line RL2, the first extension portions 410 and 411 are not parallel to the X direction, and the Y-direction positive end of the connecting portion 422 and the Y-direction negative end of the connecting portion 423 are not parallel to the Y direction. Therefore, outside of the curved portion 46, the width (length along the Y direction) of the first extension portions 410 and 411 is smaller than the width (length along the Y direction) of the curved portion 46.

[0068] A notch 414 is formed at the intersection of the outer edges 410a and 411a of the first extensions 410 and 411 with the second reference line RL2. This notch 414 is a curved portion formed in an arc shape. The formation of the curved portions 44, 45, and 46 and the notch 414, as described later, prevents stress concentration in a specific portion of the elastic member 40, which could lead to damage, when the elastic member 40 vibrates together with the mover 32.

[0069] The elastic component 40 having the above-mentioned shape is joined and fixed to the back yoke 320 by welding. Specifically, the elastic component 40 is joined to the surface of the back yoke 320 on the + side in the Z direction. That is, the elastic component 40 is arranged at a position above the back yoke 320. In this embodiment, the fixing portion 42 of the elastic component 40 is Figure 4 The six fixing points WP1 to WP6 shown are spot-welded to the back yoke 320, thereby fixing the fixing portion 42 to the back yoke 320. The number of fixing points is not limited to six.

[0070] <Fixed points WP1 to WP6>

[0071] like Figure 4 As shown, the fixing points WP1 and WP2 are provided at the connecting portion 422 of the fixing portion 42, the fixing points WP3 and WP4 are provided at the main fixing portion 421 of the fixing portion 42, and the fixing points WP5 and WP6 are provided at the connecting portion 423. Figure 4 In the figure, for the convenience of illustration, the fixed points WP1 to WP6 are represented by circles, and small dots are given inside to represent them.

[0072] Of the multiple fixed points WP1 to WP6, two fixed points WP1 and WP2 arranged along the X direction are included in the first fixed point group G1, two fixed points WP3 and WP4 arranged along the X direction are included in the second fixed point group G2, and two fixed points WP5 and WP6 arranged along the X direction are included in the third fixed point group G3. Furthermore, the first fixed point group G1, the second fixed point group G2, and the third fixed point group G3 are arranged along the Y direction (second direction) on the fixed portion 42. More specifically, a fixed point group is provided on each of the main fixed portion 421 and the pair of connecting portions 422 and 423.

[0073] The first fixed point group G1 includes fixed points WP1 and WP2, which are located in the connecting portion 422. Fixed points WP1 and WP2 are located symmetrically with respect to the second reference line RL2. Specifically, fixed points WP1 and WP2 are located at equal or substantially equal distances from the second reference line RL2 in the X direction in the connecting portion 422. More specifically, fixed point WP1 is located closer to the positive side of the second reference line RL2 in the X direction, while fixed point WP2 is located closer to the negative side of the second reference line RL2 in the X direction. In other words, the distance between fixed point WP1 and the positive-side edge 422a of the connecting portion 422 is equal to or substantially equal to the distance between fixed point WP2 and the negative-side edge 422b of the connecting portion 422 in the X direction.

[0074] The second fixed point group G2 includes fixed points WP3 and WP4, which are located on the first reference line RL1 in the main fixing portion 421. Furthermore, fixed points WP3 and WP4 are located symmetrically with respect to the second reference line RL2. That is, fixed points WP3 and WP4 are located at equal or substantially equal distances from the second reference line RL2 in the main fixing portion 421. More specifically, fixed point WP3 is located closer to the positive side of the second reference line RL2 in the X direction, while fixed point WP4 is located closer to the negative side of the second reference line RL2 in the X direction. In other words, the distance between fixed point WP3 and the positive-side edge 421a of the main fixing portion 421 is equal or substantially equal to the distance between fixed point WP4 and the negative-side edge 421b of the main fixing portion 421 in the X direction.

[0075] The fixed points WP5 and WP6 included in the third fixed point group G3 are located in the connection portion 423 at positions symmetrical with respect to the second reference line RL2. Specifically, the fixed points WP5 and WP6 are located in the connection portion 423 at equal or substantially equal distances from the second reference line RL2 along the X direction. More specifically, the fixed point WP5 is located on the positive side of the second reference line RL2 in the X direction, and the fixed point WP6 is located on the negative side of the second reference line RL2 in the X direction. In other words, the distance between the fixed point WP5 and the positive-side edge 423a of the connection portion 423 is equal or substantially equal to the distance between the fixed point WP6 and the negative-side edge 423b of the connection portion 423 in the X direction.

[0076] As described above, in each of the fixed point groups G1, G2, and G3, the distances between the fixed points WP1, WP3, and WP5 on one side and the end edges 421a, 422a, and 423a of the fixed portion 42 (on the positive side in the X direction) are equal or substantially equal to the distances between the fixed points WP2, WP4, and WP6 on the other side and the end edges 421b, 422b, and 423b on the negative side in the X direction) of the fixed portion 42. This prevents stress concentration on specific locations of the connecting portions 422 and 423 when the mover 32, including the back yoke 320 connected to the elastic component 40, vibrates in the Z direction. As a result, damage to the elastic component 40 can be suppressed. Furthermore, by arranging the fixed points WP3 and WP4 of the second fixed point group G2 in the aforementioned positional relationship, vibration of the main fixed portion 421 on the positive and negative sides in the Z direction in opposite directions due to secondary resonance can be suppressed.

[0077] Furthermore, fixed point WP1 and fixed point WP5 are located symmetrically with respect to first reference line RL1. Specifically, fixed point WP1 and fixed point WP5 are located at equal or substantially equal distances from first reference line RL1 in the Y direction. More specifically, fixed point WP1 is located on the positive side of first reference line RL1 in the Y direction, while fixed point WP5 is located on the negative side of first reference line RL1 in the Y direction.

[0078] Fixed point WP2 and fixed point WP6 are located symmetrically with respect to first reference line RL1. Specifically, fixed point WP2 and fixed point WP6 are located at equal or substantially equal distances from first reference line RL1 in the Y direction. More specifically, fixed point WP2 is located on the positive side of first reference line RL1 in the Y direction, while fixed point WP6 is located on the negative side of first reference line RL1 in the Y direction.

[0079] As described above, the fixed points WP3 and WP4 are located on the first reference line RL1. Therefore, the fixed point WP3 and the fixed point WP4 can be considered to be located symmetrically with respect to the first reference line RL1.

[0080] As described above, the multiple fixing points WP1 to WP6 are provided on the fixing portion 42 at positions symmetrically spaced relative to the first reference line RL1 and the second reference line RL2. Therefore, when the mover 32, including the back yoke 320 joined to the elastic member 40, vibrates in the Z direction, stress concentration on specific locations of the elastic member 40 is suppressed. As a result, damage to the elastic member 40, such as breakage, caused by the vibration of the mover 32 can be suppressed. In other words, the durability of the elastic member 40 can be improved.

[0081] <Operation of the Linear Vibration Motor 10>

[0082] When current flows through the FPC 50, the stator 31 is excited, generating a magnetic field that acts on the magnet 321. As described above, the stator 31 is oriented so that the coil axis is aligned or approximately aligned with the Z direction. Therefore, the direction of the magnetic field generated by the stator 31 is toward either the positive or negative side along the Z direction. This magnetic field causes the mover 32, which includes the magnet 321, and the elastic member 40, which is coupled to the back yoke 320, to move toward either the positive or negative side along the Z direction.

[0083] When the direction of the current flowing through the stator 31 is switched, the direction of the magnetic field generated by the stator 31 switches to the other of the positive and negative directions along the Z direction. As a result, the direction of the magnetic field acting on the magnet 321 is switched, and the movement direction of the mover 32 and the elastic member 40 is switched. Each time the direction of the current flowing through the stator 31 is repeatedly switched, the movement direction of the mover 32 and the elastic member 40 switches, causing the mover 32 and the elastic member 40 to vibrate along the Z direction.

[0084] As described above, the length of the first extensions 410 and 411 of the elastic member 40 along the X direction is equal to or substantially equal to the length of the first side wall panels 202 and 203 of the housing 20 along the X direction. The length of the second extensions 412 and 413 along the Y direction is equal to or substantially equal to the length of the second side wall panels 204 and 205 of the housing 20 along the Y direction. However, the height of the first side wall panels 202 and 203 in the Z direction is lower than the height of the second side wall panels 204 and 205 in the Z direction.

[0085] Therefore, even when the elastic member 40 vibrates in the positive and negative directions along the Z direction along with the mover 32, the first extensions 410 and 411 are prevented from colliding with the first sidewalls 202 and 203 of the housing 20. In other words, the elastic member 40 can vibrate without being hindered by the housing 20. In other words, the length of the steps D1 and D2 along the Z direction is formed to be greater than the maximum amplitude of vibration of the elastic member 40 along the Z direction. Specifically, the length of the steps D1 and D2, which is approximately 1.0 mm, is determined based on the maximum amplitude of vibration of the elastic member 40.

[0086] Although various embodiments and modifications have been described above, the present invention is not limited to these contents, and other aspects that can be considered within the scope of the technical concept of the present invention are also included in the scope of the present invention.

[0087] The main fixing portion 421 of the fixing portion 42 is connected to the first extension portions 410 and 411 via the connecting portions 422 and 423. However, the fixing portion 42 may not include the connecting portions 422 and 423, and the main fixing portion 421 may be connected to the first extension portions 410 and 411. In this case, the main fixing portion 421 and the first extension portions 410 and 411 are connected via the bent portion 46. Furthermore, in this case as well, the plurality of fixing points WP1 to WP6 are provided on the main fixing portion 421 so as to have the positional relationship described above.

[0088] According to the above-described embodiment, at least one of the following effects can be obtained.

[0089] (1) The linear vibration motor 10 includes a housing 20 that houses an actuator 30, and an elastic member 40 that is fixed to a mover 32 constituting the actuator 30 and the housing 20, and supports the mover 32 so that it can vibrate relative to the housing 20. The elastic member 40 includes a pair of first extensions 410 and 411 extending in a first direction (X direction), a pair of second extensions 412 and 413 extending in a second direction (Y direction), and a fixing portion 42 connected to the first extensions 410 and 411. The fixing portion 42 is located between the pair of first extensions 410 and 411 and the pair of second extensions 412 and 413, and is provided at a position overlapping with the center portion C of the elastic member 40. The fixing portion 42 is fixed to the back yoke 320 at a plurality of fixing points WP1 to WP6. The plurality of fixed points WP1 to WP6 are provided at positions symmetrical to a first reference line RL1 passing through the center portion C and parallel to the first direction, and at positions symmetrical to a second reference line RL2 passing through the center portion C and parallel to the second direction.

[0090] As a result, when the mover 32, including the back yoke 320 joined to the elastic member 40, vibrates in the Z direction, stress concentration on specific locations of the elastic member 40 is suppressed. Consequently, damage to the elastic member 40, such as breakage, caused by the vibration of the mover 32 can be suppressed. Consequently, the durability of the elastic member 40 can be improved, thereby extending the product life of the linear vibration motor 10.

[0091] (2) The fixing portion 42 is provided with a plurality of fixing point groups G1 to G3 along the second direction (Y direction), each of which includes two fixing points provided along the first direction (X direction). This can suppress stress concentration near the location where the fixing portion 42 connects to the first extension portions 410 and 411.

[0092] (3) The distances between the fixed points WP1, WP3, and WP5 on one side and the end edges 421a, 422a, and 423a on one side (the positive side in the X direction) of the fixed portion 42 are equal or substantially equal to the distances between the fixed points WP2, WP4, and WP6 on the other side and the end edges 421b, 422b, and 423b on the other side (the negative side in the X direction) of the fixed portion 42. Thus, when the mover 32 including the back yoke 320 joined to the elastic member 40 vibrates in the Z direction, stress concentration on a specific portion of the fixed portion 42 can be suppressed. As a result, damage to the elastic member 40 can be suppressed.

[0093] (4) A fixed point group is provided on each of the main fixing portion 421 and the pair of connecting portions 422 and 423 of the fixing portion 42. This prevents stress from concentrating on specific locations of the connecting portions 422 and 423 when the mover 32, including the back yoke 320 joined to the elastic member 40, vibrates in the Z direction. Consequently, damage to the elastic member 40 can be prevented. Furthermore, by arranging the fixed points WP3 and WP4 of the second fixed point group G2 to have the aforementioned positional relationship, vibration in opposite directions along the Z direction on the X-direction positive side and the X-direction negative side of the main fixing portion 421 due to secondary resonance can be prevented.

[0094] (5) The first extensions 410 and 411 are connected to the second extensions 412 and 413 and the connection parts 422 and 423 via the bent parts 44 and 46. This prevents stress from concentrating on a specific portion and causing damage to the elastic member 40 when the elastic member 40 vibrates together with the mover 32.

[0095] (6) Arc-shaped notches 414 are provided at the outer edges 410a and 411a of the first extensions 410 and 411 at positions intersecting the second reference line RL2. This can suppress the concentration of stress caused by the vibration of the elastic member 40, thereby preventing damage to the elastic member 40.

[0096] (7) The width of the first extension portions 410 and 411 along the second direction (Y direction) is smaller than the width of the fixing portion 42 along the second direction. This can suppress the concentration of stress caused by vibration of the elastic member 40, thereby suppressing damage to the elastic member 40.

[0097] In addition, the present technology can adopt the following configurations.

[0098] (1) A linear vibration motor comprising: an actuator having a mover and a stator, the mover having a magnet and a back yoke; a housing for accommodating the actuator; and an elastic member fixed to the mover and the housing for supporting the mover so as to be able to vibrate relative to the housing, the elastic member comprising: a pair of first extensions extending along a first direction intersecting a vibration direction of the mover; a pair of second extensions extending along a second direction intersecting the first direction and the vibration direction; and a fixing member connected to the first extension, the fixing member being located between the pair of first extensions and the pair of second extensions and being arranged at a position overlapping with a central portion of the elastic member, the fixing member being fixed to the back yoke at a plurality of fixing points, the plurality of fixing points being arranged at positions symmetrical with respect to a first reference line passing through the central portion and parallel to the first direction, and at positions symmetrical with respect to a second reference line passing through the central portion and parallel to the second direction.

[0099] (2) The linear vibration motor according to (1), wherein a plurality of fixing point groups are provided in the fixing portion along the second direction, and the fixing point groups include the two fixing points provided along the first direction.

[0100] (3) A linear vibration motor according to (2), wherein the fixed portion has a pair of end sides along the second direction, and the distance between the fixed point on one side included in the fixed point group and the end side on one side of the fixed portion is equal to the distance between the fixed point on the other side included in the fixed point group and the end side on the other side of the fixed portion.

[0101] (4) A linear vibration motor according to (3), wherein the fixing portion comprises: a main fixing portion extending along the first direction with the central portion as the center; and a pair of connecting portions connecting the main fixing portion and the pair of first extending portions, respectively, wherein the fixing point groups are respectively provided on the main fixing portion and the pair of connecting portions.

[0102] (5) The linear vibration motor according to (4), wherein the first extension portion is connected to the second extension portion and the connection portion via a bent portion.

[0103] (6) The linear vibration motor according to any one of (1) to (5), wherein an arc-shaped notch is provided on the outer edge of the first extending portion at a position intersecting with the second reference line.

[0104] (7) The linear vibration motor according to any one of (1) to (6), wherein a width of the first extension portion along the second direction is smaller than a width of the fixing portion along the second direction.

Claims

1. A linear vibration motor comprising: an actuator having a mover and a stator, the mover having a magnet and a back yoke; a housing for receiving the actuator; as well as an elastic member fixed to the movable element and the housing, and supporting the movable element so as to be able to vibrate relative to the housing; The elastic component has: a pair of first extension portions extending along a first direction intersecting with a vibration direction of the mover; a pair of second extending portions extending along a second direction intersecting the first direction and the vibration direction; and a fixing portion connected to the first extending portion, The fixing portion is located between the pair of first extending portions and the pair of second extending portions and is provided at a position overlapping with the center portion of the elastic member. The fixing portion is fixed to the back yoke at a plurality of fixing points. The plurality of fixing points are provided at positions symmetrical to a first reference line passing through the central portion and parallel to the first direction, and are also provided at positions symmetrical to a second reference line passing through the central portion and parallel to the second direction.

2. The linear vibration motor according to claim 1, wherein The fixing portion is provided with a plurality of fixing point groups along the second direction, and the fixing point groups include the two fixing points provided along the first direction.

3. The linear vibration motor according to claim 2, wherein: The fixing portion has a pair of end sides along the second direction, A distance between one of the fixed points included in the fixed point group and one end side of the fixed portion is equal to a distance between the other fixed point included in the fixed point group and the other end side of the fixed portion.

4. The linear vibration motor according to claim 3, wherein: The fixing portion has: a main fixing portion extending along the first direction with the central portion as the center; and a pair of connecting portions, the pair of connecting portions respectively connecting the main fixing portion and the pair of first extending portions, The fixing point groups are respectively provided at the main fixing portion and the pair of connecting portions.

5. The linear vibration motor according to claim 4, wherein: The first extension portion is connected to the second extension portion and the connection portion via a bent portion.

6. The linear vibration motor according to claim 5, wherein: An arc-shaped notch is provided on the outer edge of the first extending portion at a position intersecting the second reference line.

7. The linear vibration motor according to any one of claims 1 to 6, wherein: A width of the first extension portion along the second direction is smaller than a width of the fixing portion along the second direction.

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