Vibration Generator

Abstract

To provide a vibration generator that has high impact resistance and low production cost and can be easily assembled.SOLUTION: A vibration generator 1 has a frame 20, four coils 40 (40a, 40b, 40c, 40d) and a holder 50. The holder 50 has four columnar bodies 51 (51a, 51b, 51c, 51d) fixed to the frame 20, four arm parts 53 (53a, 53b, 53c, 53d), and one oscillator holding part 55. The holding part 55 holds a plate-like oscillator 80 constituted of a magnet 60 and a yoke 70. Each of the arm parts 53 connects each of the columnar bodies 51 to the oscillator holding part 55, and the oscillator 80 is supported displaceably relative to the columnar body 51. Each of the coils 40 is arranged to face the oscillator 80. The oscillator 80 can move at least in directions parallel and vertical to the horizontal plane when each of the coils 40 is energized.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vibration generator, and more particularly to a vibration generator that generates vibrations by passing a current through a coil to move a vibrator. [Background technology]

[0002] Various types of vibration generators that generate vibrations by moving a vibrator have been used, each of which has a structure in which a vibrator including a magnet and a weight is supported by a housing via a spring. This type of vibration generator has a coil placed near the magnet. When electricity is applied to the coil, a magnetic field is generated, and the vibrator moves while deforming the spring.

[0003] Patent Document 1 below discloses a vibration generator having a structure in which a vibrating unit having a magnet is supported via a leaf spring. In this vibration generator, a single flat coil is arranged so as to face the magnet of the vibrating unit. One end of the leaf spring is fixed to the housing using a screw. The other end of the leaf spring is fixed to the weight of the vibrating unit by caulking.

[0004] Patent Document 2 listed below discloses a vibration generator in which a magnet is attached to a mover block, and a coil is wound around a rod-shaped yoke body that is arranged along the magnet.

[0005] In addition, Patent Document 3 listed below discloses a vibration generator in which a coil is placed around the outer periphery of a shaft, a magnet is placed outside of that, and the vibration generating part of the magnet is held by upper and lower leaf springs, and when electricity is applied, it moves back and forth in the vertical direction. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-24871 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-94567 [Patent Document 3] Japanese Patent Application Laid-Open No. 2011-189337 Summary of the Invention [Problem to be solved by the invention]

[0007] [Means for solving the problem]

[0008] According to one aspect of the present invention to achieve the above object, a vibration generator includes a housing having a coil, a vibrator having a magnet, and an elastic body made of resin that holds the vibrator displaceably relative to the housing, the housing having a top surface, a bottom surface, and front, rear, left and right side surfaces, the vibrator is surrounded by the housing, and a weight is arranged in the center of the vibrator, the elastic body made of resin includes an annular holding part that holds the vibrator, a fixed part that is fixed to the housing, and a part that connects the holding part and the fixed part, the vibrator is displaceable in the axial direction of the annular holding part, and the part that connects the holding part and the fixed part is made of an elastic body made of resin. Department or Extends radially from The holding portion and the portion connecting the holding portion and the fixing portion are made of different materials. . According to another aspect of the present invention, a vibration generator comprises a frame, a coil fixed to the frame, a vibrator having a magnet, and an elastic body made of resin that holds the vibrator so that it can be displaced relative to the frame, the frame having a top surface, a bottom surface, and front, back, left and right sides, the vibrator is surrounded by the frame and has a weight placed in the center of the vibrator, the elastic body made of resin has an annular holding portion that holds the vibrator, a fixed portion fixed to the frame, and a portion that connects the holding portion and the fixed portion, the vibrator is displaceable in the axial direction of the annular holding portion, the portion that connects the holding portion and the fixed portion extends radially from the annular holding portion, and the end of the outer periphery of the vibrator is radially inside the annular holding portion. Preferably, the holding portion and the portion connecting the holding portion and the fixing portion are formed from different materials. Preferably, the vibrator includes a magnet having a space, and a weight is disposed in the space of the magnet. Preferably, the dimension in the circumferential direction of the portion connecting the holding portion and the fixed portion is the same as or different from the dimension in the axial direction of the portion connecting the holding portion and the fixed portion.

[0009] Preferably, the vibrator includes a magnet having a space, and a weight is disposed in the space of the magnet.

[0010] Preferably, the holding portion and the portion connecting the holding portion and the fixing portion are formed from different materials.

[0011] Preferably, the dimension in the circumferential direction of the portion connecting the holding portion and the fixed portion is the same as or different from the dimension in the axial direction of the portion connecting the holding portion and the fixed portion. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a plan view showing a vibration generator according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Figure 3] FIG. 2 is an exploded perspective view of the vibration generator. [Figure 4] FIG. 4 is an exploded perspective view of the vibration generator, seen from a direction different from that of FIG. 3. [Figure 5] FIG. 2 is a plan view showing a substrate, a back yoke, and a coil. [Figure 6] FIG. 2 is a cross-sectional view of the frame taken along line BB in FIG. [Figure 7] FIG. 7 is a cross-sectional view of the frame taken along line CC in FIG. 6. [Figure 8] FIG. 10 is a plan view showing a substrate, a back yoke, and a coil of a vibration generator according to a second embodiment of the present invention. [Figure 9] FIG. 10 is a plan view showing an example of a holder and a vibrator when the vibrator includes a weight. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, a vibration generator according to an embodiment of the present invention will be described.

[0014] [First embodiment]

[0015] The vibration generator has a structure in which a vibrator holding a magnet is supported by a housing so as to be displaceable relative to the housing. A coil is disposed near the vibrator. The vibration generator generates vibration force by exciting the coil and repeatedly changing at least one of the position and orientation of the vibrator relative to the housing.

[0016] Fig. 1 is a plan view showing a vibration generator in a first embodiment of the present invention. Fig. 2 is a cross-sectional view taken along line AA in Fig. 1. Fig. 3 is an exploded perspective view of the vibration generator. Fig. 4 is an exploded perspective view of the vibration generator as seen from a different direction than Fig. 3.

[0017] In FIG. 1, to facilitate understanding of the configuration of vibration generator 1, holder 50 and other components that are normally hidden by the upper surface of frame 20 are partially shown in solid lines.

[0018] In the following description, with regard to vibration generator 1, the X-axis direction of the coordinate system shown in Fig. 1 may be referred to as the left-right direction (the positive direction on the X-axis when viewed from the origin of the coordinate system is the rightward direction), and the Y-axis direction of the coordinate system shown in Fig. 2 may be referred to as the front-to-back direction (the positive direction on the Y-axis when viewed from the origin of the coordinate system is the backward direction). Also, the Z-axis direction in Fig. 2 (the direction perpendicular to the XY plane in Fig. 1) may be referred to as the up-down direction (the positive direction on the Z-axis when viewed from the origin of the coordinate system is the upward direction).

[0019] 1, vibration generator 1 broadly includes substrate 10, frame (an example of a housing) 20, back yoke 30, four coils 40 (40a, 40b, 40c, 40d), and holder 50. In the present embodiment, holder 50 includes four pillars (an example of a fixing portion) 51 (51a, 51b, 51c, 51d), four arm portions 53 (53a, 53b, 53c, 53d), and one vibrator holding portion (hereinafter sometimes simply referred to as the holding portion) 55. Holding portion 55 holds vibrator 80, which is configured from magnet 60 and yoke (an example of a magnetic plate) 70.

[0020] Vibration generator 1 is formed as a whole in the shape of a thin, approximately rectangular parallelepiped with relatively small vertical dimensions. In the present embodiment, the left-right dimension and the front-rear dimension of vibration generator 1 are approximately equal, excluding the portion of substrate 10. Vibration generator 1 is small, with external dimensions in the left-right and front-rear directions each being only about 10 to 20 mm, for example. Vibration generator 1 has a box-like external shape, with front, rear, left, and right side surfaces and a top surface formed by frame 20, and the bottom surface covered by substrate 10 and back yoke 30.

[0021] FIG. 5 is a plan view showing the substrate 10, the back yoke 30, and the coil 40. As shown in FIG.

[0022] As shown in Fig. 5, back yoke 30 in this embodiment has a flat plate shape. Back yoke 30 is attached to the bottom side of frame 20 and fixed to frame 20. A notch 31 is provided at the right edge of back yoke 30. As a result, with back yoke 30 fixed to frame 20, the interior and exterior of vibration generator 1 communicate with each other through the portion where notch 31 is provided. Back yoke 30 is made of a non-magnetic material such as stainless steel.

[0023] The substrate 10 is, for example, a flexible printed circuit board (FPC). The substrate 10 is formed so as to cover substantially the entire upper surface of the back yoke 30. The substrate 10 has a protruding piece 10b that protrudes rightward from a portion on the back yoke 30. A terminal portion 10c that can be attached to an external connector or a solder land on an external substrate is provided at the tip of the protruding piece 10b. The substrate 10 is disposed on the back yoke 30 so that the protruding piece 10b passes through the cutout portion 31 and protrudes to the outside of the frame 20. The substrate 10 is fixed to the back yoke 30 via, for example, an adhesive sheet or adhesive.

[0024] Lands 12 corresponding to each coil 40 are provided on the substrate 10. In this embodiment, a total of eight lands 12 are provided, two for each coil 40. Each land 12 is connected to a terminal of the terminal portion 10c. As a result, a drive current supplied from the outside to the terminal portion 10c is sent to each coil 40 via the lands 12.

[0025] Each of the four coils 40 is an air-core coil that is generally triangular and flat, and is formed by winding a conductor wire, for example. That is, each coil 40 is a thin coil whose dimension in the direction of the winding axis is smaller than its dimension in the direction perpendicular to the winding axis. Note that the coil 40 may be formed by slicing a wound metal foil or by stacking sheet coils. Furthermore, the coil 40 may have an elliptical shape including a circle, or a polygonal shape such as a rectangle, when viewed from above.

[0026] 2, each coil 40 is disposed on the upper surface of the substrate 10 with the winding axis direction being the up-down direction. That is, each coil 40 is disposed so as to face the vibrator 80 as will be described later.

[0027] As shown in FIG. 1 , the four coils 40 are arranged so that the direction of motion of vibrator 80 changes when the state of current supply to the four coils is changed, as described below. That is, in the present embodiment, coil 40a is arranged at the rear of the left-right center of vibration generator 1. Coil 40b is arranged to the right of the front-to-back center of vibration generator 1 in a plan view. Coil 40c is arranged at the front of the left-to-right center of vibration generator 1 in a plan view. Coil 40d is arranged to the left of the front-to-back center of vibration generator 1 in a plan view. Each coil 40 is arranged so that one vertex of its triangular shape faces the front-to-back, left-to-right center.

[0028] One of the two winding ends of each coil 40 is connected to a land 12 disposed so as to be located inside the coil 40, and the other is connected to a land 12 disposed so as to be located outside the coil 40. The winding ends of each coil 40 are respectively connected to the land 12 using, for example, solder. This allows current to flow through each coil 40 via the terminal portion 10c.

[0029] As shown in FIG. 1, the frame 20 has an overall rectangular parallelepiped shape with an open bottom. The frame 20 is formed, for example, by drawing an iron plate, but is not limited to this. In a plan view, the corners (portions between each side surface) of the frame 20 are connected via a rounded surface. As shown in FIG. 2, the frame 20 is disposed above the substrate 10 so as to cover the upper surface of the substrate 10. The frame 20 is fixed to the back yoke 30 by gluing or welding the lower portions of each side surface to the back yoke 30. In other words, the back yoke 30 is attached to the frame 20. The frame 20 may be fixed to the back yoke 30 by engaging with a protrusion provided on the back yoke 30, being fitted into the back yoke 30, or by other methods.

[0030] As described above, vibration generator 1 has a structure surrounded by frame 20, and is therefore less susceptible to the influence of surrounding magnetic fields, etc. Furthermore, the magnetic flux within vibration generator 1 is relatively less likely to leak to the outside, and is less likely to affect external devices, circuits, etc.

[0031] Furthermore, vibration generator 1 is enclosed in a box shape by frame 20 and bottom plate 30, which increases the rigidity of vibration generator 1 itself. Therefore, vibration generator 1 can reliably generate vibration. Furthermore, vibration generator 1 is easy to handle when attaching it to an external device or the like.

[0032] Holder 50 is integrally molded together with magnet 60 and yoke 70 by insert molding. That is, holder 50 and vibrator 80 are integrally molded. In the present embodiment, columnar body 51, arm portion 53, and holding portion 55 are integrally molded using an elastic body (an example of resin). For example, heat-resistant fluorine-based or silicon-based rubber can be used as the elastic body. Forming holder 50 using such rubber can improve the heat resistance of vibration generator 1. The elastic body is not limited to this, and various other elastic bodies can be used.

[0033] 3, each pillar 51 has a cylindrical shape with its height direction being the up-down direction. The height of each pillar 51 is, for example, approximately the same as or slightly smaller than the vertical dimension inside the frame 20.

[0034] 1, the four pillars 51 are arranged at positions that correspond to the four corners of the holder 50 in a plan view. The pillars 51 are arranged on the rounded portions of the side surfaces of the frame 20.

[0035] As shown in FIGS. 1 and 2, the vibrator 80 has a plate shape that is parallel to a horizontal plane (the XY plane in FIG. 1). The vibrator 80 is formed in a substantially rectangular shape with each side parallel to the front-to-back or left-to-right direction in a plan view. In particular in this embodiment, the vibrator 80 is substantially square in a plan view, but is not limited to this. The vibrator 80 may be circular, elliptical, or another polygonal shape in a plan view.

[0036] 1, vibrator 80 is disposed in the center of holder 50 in plan view, i.e., in the center of vibration generator 1. As shown in FIG. 2, vibrator 80 is disposed substantially parallel to coil 40 and faces opposite coil 40.

[0037] The magnet 60 is a permanent magnet and has a thin rectangular parallelepiped shape. The magnet 60 is magnetized, for example, so that the bottom surface portion facing the coil 40 is one pole, either an N pole or an S pole, and the top surface portion facing the yoke 70 is the other pole. However, the magnetization mode of the magnet 60 is not limited to this. For example, the bottom surface portion may be magnetized into two poles, with the N pole and the S pole separated in the front-to-rear direction, or the magnet 60 may be magnetized into four poles, with the N pole and the S pole corresponding to each coil 40 (for example, the portion close to coil 40a may be magnetized as the N pole, the portion close to coil 40b as the S pole, the portion close to coil 40c as the N pole, and the portion close to coil 40d as the S pole).

[0038] The yoke 70 is a magnetic plate that is approximately square in plan view and is attached so as to cover the upper surface of the magnet 60. The yoke 70 and the magnet 60 are joined to each other by, for example, spot welding or adhesive bonding to form an integrated vibrator 80. In this embodiment, the vibrator 80 and the holder 50 are integrally molded by insert molding, with the yoke 70 and the magnet 60 joined to form the vibrator 80. For example, the yoke 70 may have ears (not shown) that partially protrude outward laterally from each of two opposing sides, and the vibrator 80 may be attached to the holder 50 so that the ears fit into the holding portions 55 of the holder 50. This makes it difficult for the vibrator 80 to fall off the holder 50.

[0039] The four arms 53 are formed so as to connect each side surface of the rectangular parallelepiped holding portion 55 to the columnar body 51 closest to that side surface. Each arm 53 is formed like a beam extending substantially perpendicularly from each side surface of the holding portion 55. As shown in FIG. 3 and other figures, the arm 53 is formed of an elastic material and therefore easily bends in response to displacement or changes in posture of the vibrator 80. In other words, the dimensions of the arm 53 are set so that the arm 53 bends appropriately when the vibrator 80 is vibrated, as will be described later. For example, in this embodiment, the width dimension of each arm 53 (the direction parallel to each side of the holding portion 55 in a plan view) is smaller than the vertical dimension (up-down direction). This makes each arm 53 more likely to bend horizontally than vertically. Note that the relationship between the width dimension and the vertical dimension of each arm 53 is not limited thereto. The width dimension of each arm 53 may be equal to or greater than the vertical dimension.

[0040] In this way, the four arm portions 53 are each formed to be easily flexible in the horizontal and vertical directions, and therefore the vibrator 80 can be displaced in the horizontal and vertical directions relative to the columnar body 51. In other words, the vibrator 80 is supported by the arm portions 53 so as to be displaceable in directions substantially parallel to the horizontal plane and directions substantially perpendicular to the horizontal plane.

[0041] Holder 50 is attached to frame 20 by fixing each of four pillars 51 to frame 20. This forms the basic structure of vibration generator 1 in which vibrator 80 is supported by holder 50, which is integrally molded separately from frame 20, so as to be displaceable relative to frame 20.

[0042] In the present embodiment, the pillars 51 are attached to the frame 20 by engaging with the engaging portions 21 (21a, 21b, 21c, 21d) provided on the frame 20. This allows the holder 50 to be easily attached to the frame 20.

[0043] Fig. 6 is a cross-sectional view of the frame 20 taken along line BB in Fig. 1. Fig. 7 is a cross-sectional view of the frame 20 taken along line CC in Fig. 6.

[0044] 7, in this embodiment, the engagement portions 21 are provided at the corners of the frame 20 in a plan view. Each of the four engagement portions 21 has two claw portions 22, 23: a first claw portion 22 (22a, 22b, 22c, 22d) and a second claw portion 23 (23a, 23b, 23c, 23d).

[0045] 6, in each engagement portion 21, the two claws 22, 23 are each formed by providing a U-shaped notch in a part of the side surface of the frame 20 and pressing the inside of the notch toward the inside of the frame 20. Therefore, each of the claws 22, 23 is molded integrally with the frame 20. By forming each of the claws 22, 23 in this manner, gaps 25 (25a, 25b, 25c, 25d) are partially provided on the side surface of the frame 20.

[0046] In this embodiment, the claws 22, 23 are formed in a shape corresponding to the shape of the columnar body 51. That is, while the columnar body 51 is cylindrical, the claws 22, 23 are formed in a shape that fits along the side peripheral surface of the columnar body 51. As shown in Fig. 7 , each engagement portion 21 is formed so that, in a plan view, the rounded surface portion between the claws 22, 23 and the side surface of the frame 20 surrounds at least half of the outer peripheral surface of the columnar body 51 that is placed in that engagement portion 21.

[0047] When the holder 50 is placed on the frame 20, first, the four pillars 51 are fitted into the four engagement portions 21. As a result, each pillar 51 is sandwiched between the claw portions 22, 23 of the engagement portion 21 (an example of engagement). In other words, the side peripheral surface of each pillar 51 is gripped by the claw portions 22 and 23 of the engagement portion 21 (an example of engagement). By engaging the pillars 51 with the engagement portions 21 in this way, the pillars 51 are fixed to the frame 20, and the holder 50 is attached to the frame 20.

[0048] Each of the claws 22, 23 is crimped to the columnar body 51 with each columnar body 51 fitted into the engagement portion 21. As shown by the arrows in Fig. 7, for example, with respect to engagement portion 21d, first claw 22d is pushed forward (downward in Fig. 7), and second claw 23d is pushed rightward (rightward in Fig. 7). By crimping the claws 22, 23 in this manner, the claws 22, 23 bite into each columnar body 51, and the columnar body 51 is fixed to the frame 20 more firmly.

[0049] In vibration generator 1, each coil 40 generates a magnetic field for moving vibrator 80 relative to frame 20. That is, each coil 40 is excited when a current is passed through it. This generates a magnetic field in the vertical direction. When a magnetic field is generated, magnet 60 is affected by this magnetic field, generating a repulsive and attractive force. As a result, a force acts on vibrator 80, displacing and changing the posture of vibrator 80 in a direction that depends on the direction of the magnetic field and the arrangement of the magnetic poles of magnet 60. As a result, vibrator 80 is displaced while bending each arm portion 53. Therefore, when an alternating current is passed through at least one of the four coils 40, vibrator 80 performs periodic motion, such as a reciprocating motion, relative to frame 20. As a result, vibration generator 1 generates a vibration force.

[0050] When the AC current value decreases and the magnetic field weakens or disappears, the restoring force of arm portion 53 causes vibrator 80 to return to the center of vibration generator 1 in a plan view. At this time, arm portion 53 is an elastic body, and the energy consumed by arm portion 53 is relatively large. Therefore, the vibration is quickly damped.

[0051] In this embodiment, magnet 60 is magnetized so that the bottom surface portion facing coil 40 has one pole, either an N pole or an S pole. Therefore, by applying an AC current to each of four coils 40 in the following manner, vibrator 80 can be caused to reciprocate relative to frame 20 in a predetermined direction, such as the X-axis direction (first movement direction), the Y-axis direction (second movement direction), or the Z-axis direction (third movement direction).

[0052] To cause vibrator 80 to reciprocate in the X-axis direction, for example, first, a clockwise current is passed through coil 40d, and a counterclockwise current is passed through coil 40b. This causes vibrator 80 to move in one direction, either left or right. Thereafter, a counterclockwise current is passed through coil 40d, and a clockwise current is passed through coil 40b. This causes vibrator 80 to move in the opposite direction. By repeatedly passing a current alternately through coils 40d and 40b in this manner, vibrator 80 can be caused to reciprocate repeatedly in the X-axis direction, thereby generating vibrations.

[0053] To reciprocate vibrator 80 in the Y-axis direction, for example, first, a clockwise current is passed through coil 40a, and a counterclockwise current is passed through coil 40c. This causes vibrator 80 to move in one direction, either forward or backward. Thereafter, a counterclockwise current is passed through coil 40a, and a clockwise current is passed through coil 40c. This causes vibrator 80 to move in the opposite direction. By repeatedly passing a current alternately through coil 40a and coil 40c in this manner, vibrator 80 can be repeatedly reciprocated in the Y-axis direction, generating a vibration pattern different from that generated when vibrator 80 is reciprocated in the X-axis direction.

[0054] When vibrator 80 is caused to reciprocate in the Z-axis direction, for example, clockwise current is first passed through all coils 40a, 40b, 40c, and 40d. This causes vibrator 80 to move in one direction, either up or down. Then, counterclockwise current is passed through all coils 40a, 40b, 40c, and 40d. This causes vibrator 80 to move in the opposite direction. By repeating this process of alternately passing current through all coils 40a, 40b, 40c, and 40d, vibrator 80 can be caused to repeatedly reciprocate in the Z-axis direction. Because vibrator 80 is moved in the Z-axis direction, it is possible to generate vibrations with a different pattern than when vibrator 80 is reciprocated in the axial or Y-axis directions.

[0055] Note that vibrator 80 is displaced by being attracted to or repelled by each coil 40. Therefore, when vibrator 80 is displaced in the X-axis, Y-axis, or Z-axis directions parallel to the horizontal plane, strictly speaking, it tilts slightly from a horizontal position or displaces up or down. However, the amount of such displacement or change in position is relatively small and does not particularly affect the effect, so this is expressed here without taking this into consideration.

[0056] Furthermore, in vibration generator 1 configured in this manner, by passing current through the four coils at different times, vibrator 80 can be made torsionally move in the rotational direction. For example, by applying current to each coil 40 with a 90-degree phase shift of the AC current, vibrator 80 can be made torsionally move. That is, first, a clockwise current is passed through coil 40d and a counterclockwise current is passed through coil 40b. Next, a clockwise current is passed through coil 40a and a counterclockwise current is passed through coil 40c. After that, a counterclockwise current is passed through coil 40d and a clockwise current is passed through coil 40b. Then, a counterclockwise current is passed through coil 40a and a clockwise current is passed through coil 40c. When currents are passed in this manner, the corners of vibrator 80 located above each coil 40 rise up one by one in a clockwise direction in a plan view, and simultaneously, the corners corresponding to the opposite corners sink down. In this way, oscillator 80 periodically changes its posture around an axis that is parallel to the Z axis and passes through approximately the center of oscillator 80. In other words, oscillator 80 performs torsional motion around an axis that is parallel to the Z axis and passes through approximately the center of oscillator 80, while maintaining a posture that is tilted from the horizontal.

[0057] The reciprocating motion of the vibrator 80 in the X-axis direction, the Y-axis direction, the Z-axis direction, and the torsional motion as described above can be easily switched in the same vibration generator 1 by changing the mode of current flow to each coil 40.

[0058] When vibrator 80 is moved in the Z-axis direction, it is conceivable that holder 50 may come into contact with coil 40, or that holder 50 may come into contact with frame 20. For this reason, it is preferable to provide a protective member on at least one side of holder 50 in the Z-axis direction, i.e., above or below holder 50.

[0059] For example, if the holder 50 and the coil 40 come into contact with each other, the coil 40 may be damaged. To prevent damage to the coil 40, a protective member such as the following may be provided. That is, a soft silicone member (an example of a protective member) may be attached to the bottom surface of the holder 50 (the surface facing the coil 40) in advance. The coil 40 may also be protected by being coated with silicone resin (an example of a protective member). Another protective member may be provided between the coil 40 and the holder 50, such as cellophane or a rubber member. For example, as shown in FIG. 2, the coil 40 may be protected by attaching a silicone sheet 600 (an example of a protective member) to the upper surface of the coil 40.

[0060] The same applies to contact between the holder 50 and the frame 20. That is, for example, another member such as cellophane or a rubber member may be placed between the frame 20 and the holder 50 as a protective member.

[0061] In the vibration generators having the structures described in Patent Documents 1 to 3, the vibration direction of the vibrator is determined by the arrangement of the magnets and coils, the shape of the leaf spring that holds the vibrator, and the like. That is, in these vibration generators, the vibration direction of the vibrator is limited to one direction. Therefore, when generating vibrations with these vibration generators, there is a problem in that the mode of vibration generation (vibration pattern) tends to be monotonous.

[0062] As described above, in this embodiment, four coils 40 are arranged face-to-face with vibrator 80, and vibrator 80 can move in response to excitation of each coil 40. Providing four coils allows current to be applied to each coil 40 in various ways. Therefore, using the same vibration generator 1, the direction of movement and vibration strength of vibrator 80 can be changed in various ways, and vibrations of various patterns can be generated. Vibration generator 1 can also be easily made thin, allowing it to be used for a wide range of applications.

[0063] Conventional vibration generators support a vibrator using a leaf spring attached to a housing. However, for example, the leaf spring is attached to the housing using screws, which creates a complex structure for attaching the leaf spring to the housing. This increases the assembly time and number of components, thereby increasing the manufacturing cost of the vibration generator. This problem has become more pronounced as demand for smaller and thinner vibration generators increases. As vibration generators become smaller, the components also become smaller, necessitating the use of attachment methods such as spot welding instead of screw fastening or crimping, which complicates the structure of the attachment between the components. For example, when spot welding is used to attach the leaf spring to the housing, welding is required at many locations to maintain high reliability of the vibration generator, which can be time-consuming during manufacturing. This is because spot-welded areas are relatively vulnerable to impact forces. In contrast, conventional structures in which the spring and the frame are integrally molded do not present the above-mentioned problems associated with the method of joining the spring and the housing. However, in this case, there is a problem in that the material used for the housing is limited to those that can be molded integrally with the spring portion.

[0064] To address these problems, in the present embodiment, holder 50 including pillar-shaped body 51 is integrally molded, and holder 50 is attached to frame 20 by fitting pillar-shaped body 51 into engaging portion 21. Holder 50 can be easily attached to frame 20, and the number of parts can be kept small, thereby reducing the manufacturing cost of vibration generator 1. Furthermore, because holder 50 and frame 20 are each integrally formed, the attachment portion between holder 50 and frame 20 does not become brittle. This improves the reliability of vibration generator 1 against impact. Because no additional members such as screws are required to attach holder 50 to frame 20, vibration generator 1 can be made smaller, thinner, and lighter.

[0065] When using a conventional structure in which the spring portion supporting the vibrator and the housing are integrally molded from resin, there is a problem in selecting the material, as the spring portion and the housing must be made of the same material. However, in this embodiment, the holder 50 and the frame 20 are made of separate parts, which reduces the number of parts. Furthermore, while maintaining a simple structure that is easy to assemble, the material of the frame 20 can be selected appropriately. Therefore, for example, the frame 20 can be configured to fulfill its role without providing a separate component that functions as a magnetic circuit or magnetic shield.

[0066] Holder 50 is configured by integrally molding columnar body 51, arm portion 53, and vibrator holding portion 55 using an elastic body. This reduces the number of parts and enables holder 50 to be manufactured easily. In the present embodiment, magnet 60 and yoke 70 are insert-molded together with holder 50, making it possible to easily configure holder 50 in a state where vibrator 80 is held, and further simplifying the manufacturing process of vibration generator 1.

[0067] The engagement portion 21 is formed integrally with the frame 20 by providing notches in parts of the side surfaces of the frame 20 to form the claw portions 22, 23. This allows for a reduction in the number of parts, further reducing manufacturing costs.

[0068] The mounting structure of holder 50 to frame 20 is such that cylindrical pillar body 51 is gripped by two claws 22, 23. Therefore, while simplifying the structure of vibration generator 1, pillar body 51 can be reliably positioned on frame 20, improving the mounting accuracy of holder 50 to frame 20. Claws 22, 23 are configured to be crimped to pillar body 51, so holder 50 can be mounted more firmly to frame 20.

[0069] Because substrate 10 is an FPC, the vertical dimension of vibration generator 1 can be reduced compared to when a double-sided substrate is used. Furthermore, the shape of back yoke 30 can be simplified, allowing for reduced manufacturing costs.

[0070] [Second embodiment]

[0071] The basic configuration of the vibration generator in the second embodiment is the same as that in the first embodiment, and therefore description thereof will not be repeated here. In the second embodiment, the arrangement of the coils is different from that in the first embodiment.

[0072] FIG. 8 is a plan view showing a substrate, a back yoke, and a coil of a vibration generator according to a second embodiment of the present invention.

[0073] 8, four coils 140 (140a, 140b, 140c, 140d) are also arranged in the second embodiment. The four coils 140 are arranged so that the direction of motion of the vibrator 80 changes when the state of current supply to the four coils 140 is changed, as will be described later.

[0074] In the second embodiment, coil 140a is disposed at the rear left of vibration generator 1. Coil 140b is disposed at the rear right of vibration generator 1 in a plan view. Coil 140c is disposed at the front right of vibration generator 1 in a plan view. Coil 140d is disposed at the front left of vibration generator 1 in a plan view. That is, in a plan view, two coils 140b and 140d are disposed at positions corresponding to a direction rotated 45 degrees around an axis perpendicular to the horizontal plane from a first direction of movement (left-right direction) of vibrator 80, and the other two coils 140a and 140c are disposed at positions corresponding to a direction rotated 45 degrees around an axis perpendicular to the horizontal plane from a third direction of movement (front-back direction) of vibrator 80. Each coil 140 is disposed so that one vertex of its triangular shape faces the center in the front-rear and left-right directions.

[0075] One of the two winding ends of each coil 140 is connected to a land 12 disposed so as to be located inside the coil 140, and the other is connected to a land 12 disposed so as to be located outside the coil 140. The winding ends of each coil 140 are respectively connected to the land 12 using, for example, solder. This allows current to flow through each coil 140 via the terminal portion 10c.

[0076] In the second embodiment, coil 140 is thus positioned offset from the direction of movement of vibrator 80, and vibrator 80 can be driven as follows. That is, to reciprocate vibrator 80 in the X-axis direction, for example, first, a clockwise current is passed through coils 140a and 140d, and a counterclockwise current is passed through coils 140b and 140c. This causes vibrator 80 to move in one direction, either left or right. Thereafter, a counterclockwise current is passed through coils 140a and 140d, and a clockwise current is passed through coils 140b and 140c. This causes vibrator 80 to move in the opposite direction to the above.

[0077] In this way, by repeatedly passing a current alternately through the combination of coils 140a and 140d and the combination of coils 140b and 140c, it is possible to repeatedly reciprocate vibrator 80 in the X-axis direction, thereby generating vibrations. In this case, compared to the first embodiment, the magnitude of the magnetic field that can be generated by coil 140 is doubled, and it is possible to generate larger vibrations.

[0078] To reciprocate vibrator 80 in the Y-axis direction, for example, first, a clockwise current is passed through coils 140a and 140b, and a counterclockwise current is passed through coils 140c and 140d. This causes vibrator 80 to move in either the forward or backward direction. Thereafter, a counterclockwise current is passed through coils 140a and 140b, and a clockwise current is passed through coils 140c and 140d. This causes vibrator 80 to move in the opposite direction to the above.

[0079] In this way, by repeatedly passing a current alternately through the combination of coils 140a and 140b and the combination of coils 140c and 140d, it is possible to repeatedly reciprocate vibrator 80 in the Y-axis direction, generating a vibration pattern different from that generated by reciprocating vibrator 80 in the X-axis direction. In this case, compared to the first embodiment, the strength of the magnetic field that can be generated from coil 140 is doubled, and it is possible to generate larger vibrations.

[0080] When vibrator 80 is caused to reciprocate in the Z-axis direction, current can be passed through the coil in the manner described in the first embodiment. This allows vibrator 80 to move up and down. Vibration can be generated by repeatedly reciprocating vibrator 80 up and down.

[0081] In the second embodiment, the arrangement of coils 140 is not limited to the above. For example, at least two of the multiple coils may be arranged at positions shifted from the direction of movement of vibrator 80 so as to be symmetrical with respect to the direction of movement of vibrator 80 in a plan view.

[0082] [others]

[0083] The frame is not limited to iron and may be made of other materials. For example, it may be made of resin and formed separately from the holder. The frame may not have a top or bottom surface and may surround the holder in a plan view. The frame may have a shape other than a square in a plan view.

[0084] The back yoke and circuit board may not be provided. For example, a member made of another material may be provided instead of the back yoke. The circuit board may also be a printed wiring board such as a double-sided board. In this case, the back yoke is not necessary, and a terminal portion for supplying electricity to the coil may be provided, for example, on the bottom surface of the vibration generator.

[0085] The number of pillars and the number of arms are not limited to those described above. Furthermore, the pillars do not have to be cylindrical, and may be polygonal. The holder may not be integrally molded, but may be formed by assembling multiple members.

[0086] The structure for attaching the holder to the frame is not limited to the structure in which the pillars are engaged with two claws that sandwich the pillars, but may be any structure in which a fixing portion of another shape on the holder engages with an engaging portion formed on the frame. For example, the frame may be formed with a hole-shaped engaging portion, and a protrusion on the holder may be fitted into the engaging portion to attach the holder to the frame. Alternatively, each pillar may be provided with a through-hole or a bottomed hole, and four support posts may be provided at the four corners of the frame, with the support posts passing through the through-holes or bottomed holes to secure the holder to the frame.

[0087] The holder is not limited to being formed by single-color molding, but may be formed by integrally molding the columnar body and holding portion, and the arm portion by two-color molding using different materials.

[0088] The structure for attaching the vibrator to the holder, i.e., the structure for attaching the magnet and yoke to the holder, is not limited to insert molding. For example, in a process separate from the molding of the holder, the magnet and yoke joined to each other by welding or the like may be incorporated into the integrally molded holder and then glued. Alternatively, the holder and yoke may be integrally formed, and then the magnet may be attached to the yoke portion.

[0089] The vibrator may include a weight in addition to the magnet. This allows for a large vibration force to be obtained. Furthermore, the required vibration force can be easily adjusted regardless of the size and length of the arm or the material of the elastic body.

[0090] FIG. 9 is a plan view showing an example of a holder and a vibrator in the case where the vibrator includes a weight.

[0091] As shown in FIG. 9 , the configuration of the holder 50 and the yoke 70 is the same as that in the above-described embodiment. The vibrator 180 shown in the figure includes a weight 185. That is, the vibrator 180 has a magnet 160, a yoke 70, and a weight 185. A space for arranging the weight 185 is provided in the magnet 160, and the weight 185 is disposed so as to be embedded in the magnet 160. By providing the weight 185 in this manner, the weight of the vibrator 180 can be increased while avoiding an increase in the size of the vibration generator. In the example shown in FIG. 9 , the weight 185 is disposed in the center of the magnet 160, away from the coil 40. Therefore, compared to the above-described embodiment in which the weight 185 is not provided, there is not much impact on the generation of force for moving the vibrator 180.

[0092] The above-described embodiments should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0093] 1 vibration generator 10 Substrate 20 Frame (example of a housing) 21(21a,21b,21c,21d) Engagement part 22(22a, 22b, 22c, 22d) First claw 23(23a, 23b, 23c, 23d) Second claw 40(40a, 40b, 40c, 40d), 140(140a, 140b, 140c, 140d) coil 50 holder 51 (51a, 51b, 51c, 51d) columnar body (an example of a fixing part) 53 (53a, 53b, 53c, 53d) Arm part 55 Vibrator holding part 60,160 magnets 70 York 80,180 transducers 600 Silicone sheet (an example of a protective material)

Claims

1. a housing having a coil; a vibrator having a magnet; an elastic body made of resin that holds the vibrator displaceably relative to the housing; The housing has a top surface, a bottom surface, and front, rear, left, and right side surfaces, the vibrator is enclosed in the housing, A weight is placed at the center of the vibrator, the elastic body made of resin includes an annular holding portion that holds the vibrator, a fixed portion that is fixed to the housing, and a portion that connects the holding portion and the fixed portion, the vibrator is displaceable in an axial direction of the annular holding portion, A vibration generator, wherein a portion connecting the holding portion and the fixed portion extends radially from the annular holding portion, and the holding portion and the portion connecting the holding portion and the fixed portion are formed of different materials.

2. A frame, a coil fixed to the frame; a vibrator having a magnet; an elastic body made of resin that holds the vibrator displaceably relative to the frame; The frame has a top surface, a bottom surface, and front, rear, left, and right side surfaces, the vibrator is surrounded by the frame, A weight is placed at the center of the vibrator, the elastic body made of resin includes an annular holding portion that holds the vibrator, a fixing portion that is fixed to the frame, and a portion that connects the holding portion and the fixing portion, the vibrator is displaceable in an axial direction of the annular holding portion, a portion connecting the holding portion and the fixing portion extends radially from the annular holding portion, an end of an outer circumferential portion of the vibrator is located inside the annular holding portion in the radial direction; Vibration generator.

3. A vibration generator as described in Claim 2, wherein the holding portion and the portion connecting the holding portion and the fixed portion are formed of different materials.

4. the vibrator includes the magnet having a space therebetween, The vibration generator according to claim 1 , wherein the weight is disposed in the space surrounding the magnet.

5. 5. The vibration generator according to claim 1, wherein a circumferential dimension of a portion connecting the holding portion and the fixed portion is the same as or different from an axial dimension of the portion connecting the holding portion and the fixed portion.

Images