Vibration actuator

Abstract

To provide a vibration actuator reduced in thickness.SOLUTION: A vibration actuator 10 includes a plate-shaped magnet 22, 23, 24 including: a magnet back surface 22a, 23a, 24a attached to a movable plate 21; and a magnet front surface 22b, 23b, 24b located on an opposite side of the magnet back surface and facing a fixed plate 31. The vibration actuators 10 includes a plate-shaped coil including: a coil back surface 33a, 34a attached to the fixed plate 31; and a coil front surface 33b, 34b located on an opposite side of the coil back surface and facing the movable plate 21. The coil front surface of the plate-shaped coil is located closer to the magnet back surface than the magnet front surface of the plate-shaped magnet.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to vibration actuators. [Background technology]

[0002] Devices such as smartphones, tablets, and game controllers are equipped with a vibration feedback function that provides users with a tactile sensation through vibration. To realize this vibration feedback function, a linear vibration actuator that vibrates a mover using electromagnetic force has been proposed (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 151232 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the linear vibration actuator described in Patent Document 1 has a coil and a magnet that are stacked in the thickness direction. However, stacking the coil and the magnet in the thickness direction causes the thickness of the vibration actuator, which is called a linear vibration actuator, to increase. Since devices such as smartphones are required to be thin, there is also a demand for the vibration actuators incorporated in the devices to be thin. [Means for solving the problem]

[0005] According to the present disclosure, a vibration actuator has a first plate and a second plate facing the first plate. The vibration actuator has a plate-shaped magnet having a magnet back surface attached to the first plate and a magnet front surface located on the opposite side of the magnet back surface and facing the second plate. The vibration actuator has a plate-shaped coil having a coil back surface attached to the second plate and a coil front surface located on the opposite side of the coil back surface and facing the first plate. The vibration actuator has an elastic member having a first end portion attached to the first plate and a second end portion attached to the second plate. The coil front surface of the plate-shaped coil is located closer to the magnet back surface than the magnet front surface of the plate-shaped magnet. Effect of the Invention

[0006] According to the present disclosure, a thinner vibration actuator can be achieved. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view showing a smartphone equipped with a vibration actuator according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a perspective view showing the vibration actuator. [Diagram 3] FIG. 3 is an exploded perspective view showing the internal structure of the vibration actuator. [Figure 4] FIG. 4 is a cross-sectional view showing the vibration actuator taken along the line AA in FIG. [Diagram 5] FIG. 5 is a cross-sectional view showing the vibration actuator shown in FIG. 4 in an exploded state. [Figure 6] FIG. 6 is a perspective view showing the vibration actuator with the movable plate removed. [Figure 7] FIG. 7 is a diagram showing an operating state of the vibration actuator. [Figure 8] FIG. 8 is a diagram showing an operating state of the vibration actuator. [Figure 9A]FIG. 9A is a simplified diagram showing a vibration actuator according to another embodiment of the present disclosure. [Figure 9B] FIG. 9B is a simplified diagram showing a vibration actuator according to another embodiment of the present disclosure. [Figure 9C] FIG. 9C is a simplified diagram showing a vibration actuator according to another embodiment of the present disclosure. [Figure 9D] FIG. 9D is a simplified diagram showing a vibration actuator according to another embodiment of the present disclosure. [Figure 10] FIG. 10 is a perspective view showing a vibration actuator according to another embodiment of the present disclosure. [Figure 11] FIG. 11 is an exploded perspective view showing the internal structure of the vibration actuator. [Figure 12] FIG. 12 is a diagram showing the positional relationship between the openings formed in the movable plate and the fixed plate, and the plate magnets and plate coils. [Figure 13] FIG. 13 is a cross-sectional view showing the vibration actuator taken along line BB in FIG. [Figure 14A] FIG. 14A is a perspective view showing a movable plate and a fixed plate provided in a vibration actuator according to another embodiment of the present disclosure. [Figure 14B] FIG. 14B is a perspective view showing a movable plate and a fixed plate provided in a vibration actuator according to another embodiment of the present disclosure. [Figure 15A] FIG. 15A is a perspective view showing a movable plate and a fixed plate provided in a vibration actuator according to another embodiment of the present disclosure. [Figure 15B] FIG. 15B is an exploded perspective view of the movable plate and the fixed plate shown in FIG. 15A. [Figure 16] FIG. 16 is a diagram showing the positional relationship between the auxiliary plate, the plate magnet, and the plate coil. [Figure 17A] FIG. 17A is a perspective view showing a movable plate and a fixed plate provided in a vibration actuator according to another embodiment of the present disclosure. [Figure 17B]FIG. 17B is an exploded perspective view of the movable plate and the fixed plate shown in FIG. 17A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, the same or substantially the same configurations and elements will be denoted by the same reference numerals and repeated description will be omitted.

[0009] <Embodiment 1> <Devices equipped with vibration actuators> FIG. 1 is a perspective view showing a smartphone 11 equipped with a vibration actuator 10 according to an embodiment of the present disclosure. As shown in FIG. 1, the vibration actuator 10 is attached to a display 12 of the smartphone 11, which is an electronic device. By controlling the vibration pattern of the display 12 using the vibration actuator 10, a user who touches the display 12 can be given a tactile sensation such as a click sensation due to vibration. In the above description, the vibration actuator 10 is attached to the display 12, but this is not limited to this, and the vibration actuator 10 may be attached to the housing of the smartphone 11. In this case, the vibration pattern of the smartphone 11 can be controlled using the vibration actuator 10, and a tactile sensation due to vibration can be given to a user who touches the smartphone 11. These vibration feedback technologies are also called haptics technologies. The vibration actuator 10 is also called a linear vibration actuator, a linear vibration motor, or the like.

[0010] An electronic control unit (not shown) including a microcontroller, a drive circuit, and the like is connected to the vibration actuator 10. By using this electronic control unit to control the current flowing through a plate-shaped coil (described later), the vibration actuator 10 can be vibrated in a predetermined vibration pattern. In the illustrated example, the vibration actuator 10 is incorporated in a smartphone 11, but this is not limiting, and the vibration actuator 10 may be incorporated in other devices. For example, the vibration actuator 10 may be incorporated in a mobile device such as a tablet, the vibration actuator 10 may be incorporated in an in-vehicle display mounted in a vehicle, or the vibration actuator 10 may be incorporated in an operating device such as a game controller or a joystick.

[0011] <Vibration actuator structure> Fig. 2 is a perspective view showing vibration actuator 10, and Fig. 3 is an exploded perspective view showing the internal structure of vibration actuator 10. Fig. 4 is a cross-sectional view showing vibration actuator 10 taken along line AA in Fig. 2, and Fig. 5 is a cross-sectional view showing the disassembled state of vibration actuator 10 shown in Fig. 4. Furthermore, Fig. 6 is a perspective view showing vibration actuator 10 with movable plate 21 removed.

[0012] As shown in Figures 2 and 3, the vibration actuator 10 has a mover unit 20 including plate-shaped magnets 22, 23, and 24, and a stator unit 30 including plate-shaped coils 33 and 34. As shown in Figures 3 and 5, the mover unit 20 has a movable plate (first plate) 21 made of a non-magnetic material, three plate-shaped magnets 22, 23, and 24 attached to the movable plate 21, and a frame-shaped weight 25 attached to the movable plate 21. The stator unit 30 has a fixed plate (second plate) 31 made of a non-magnetic material, a flexible printed circuit board 32 attached to the fixed plate 31, and two plate-shaped coils 33 and 34 attached to the flexible printed circuit board 32. As shown in Figures 3, 4, and 5, the movable plate 21 and the fixed plate 31 face each other.

[0013] Incidentally, austenitic stainless steel such as SUS301 or SUS304 can be used as the non-magnetic material forming the movable plate 21 and the fixed plate 31. The non-magnetic material is not limited to austenitic stainless steel, and the movable plate 21 and the fixed plate 31 may be formed using titanium, copper, aluminum, or the like. The plate-shaped magnets 22, 23, 24 and the weight 25 are attached to the movable plate 21 by adhesion or the like, and the plate-shaped coils 33, 34, the flexible printed circuit board 32, and the like are attached to the fixed plate 31 by adhesion or the like.

[0014] 5, the plate-shaped magnets 22, 23, 24 serving as permanent magnets constituting the mover unit 20 have magnet back surfaces 22a, 23a, 24a attached to the movable plate 21, and magnet front surfaces 22b, 23b, 24b located on the opposite side of the magnet back surfaces 22a, 23a, 24a and facing the fixed plate 31. Furthermore, the width dimension W1 of the plate-shaped magnet 23 located in the center is larger than the width dimension W2 of the plate-shaped magnets 22, 24 located at both ends. In other words, the magnetic force of the plate-shaped magnet 23 located in the center is stronger than the magnetic force of the plate-shaped magnets 22, 24 located at both ends.

[0015] The plate coils 33 and 34 constituting the stator unit 30 have coil back surfaces 33a and 34a attached to the fixed plate 31 via the flexible printed circuit board 32, and coil front surfaces 33b and 34b located on the opposite side of the coil back surfaces 33a and 34a and facing the movable plate 21. As shown in FIG. 3, the plate coil 33 has a pair of straight portions 40 and 41 parallel to each other, and a pair of bent portions 42a and 42b connecting the straight portions 40 and 41. The plate coil 34 has a pair of straight portions 44 and 45 parallel to each other, and a pair of bent portions 46a and 46b connecting the straight portions 44 and 45. These plate coils 33 and 34 are air-core coils formed by winding electric wires, and air-core portions 43 and 47, which are elongated hole-shaped spaces, are provided in the center of the plate coils 33 and 34.

[0016] As shown in FIG. 3 and FIG. 5, the vibration actuator 10 has four rubber dampers (elastic members) 48 that connect the movable plate 21 and the fixed plate 31. The rubber dampers 48 have a first end 48a that is attached to the movable plate 21 by adhesion or the like, and a second end 48b that is attached to the fixed plate 31 by adhesion or the like. In this way, the movable plate 21 and the fixed plate 31 are connected via the rubber dampers 48, so that the movable plate 21 can be displaced relative to the fixed plate 31 by a stroke according to the amount of elastic deformation of the rubber dampers 48. As shown in FIG. 4 and FIG. 5, the fixed plate 31 is attached to the display 12 or the like that constitutes the smartphone 11. When the vibration actuator 10 is attached to the housing of the smartphone 11, the fixed plate 31 is attached to the housing of the smartphone 11.

[0017] 4 and 5, the plate magnets 22, 23, 24 and the plate coils 33, 34 are arranged so that the magnet surfaces 22b, 23b, 24b and the coil surfaces 33b, 34b do not face each other in the thickness direction of the vibration actuator 10. In other words, as shown in Figures 4 and 6, when the movable plate 21 and the fixed plate 31 are connected via the rubber damper 48, the plate coil 33 is housed between the plate magnet 22 and the plate magnet 23, and the plate coil 34 is housed between the plate magnet 23 and the plate magnet 24. That is, the magnet surfaces 22b, 23b, 24b of the plate-shaped magnets 22, 23, 24 are located closer to the fixed plate 31 than the coil surfaces 33b, 34b of the plate-shaped coils 33, 34, and the coil surfaces 33b, 34b of the plate-shaped coils 33, 34 are located closer to the movable plate 21 than the magnet surfaces 22b, 23b, 24b of the plate-shaped magnets 22, 23, 24.

[0018] In other words, the coil surfaces 33b, 34b of the plate-shaped coils 33, 34 are located closer to the magnet back surfaces 22a, 23a, 24a than the magnet surfaces 22b, 23b, 24b of the plate-shaped magnets 22, 23, 24, and the magnet surfaces 22b, 23b, 24b of the plate-shaped magnets 22, 23, 24 are located closer to the coil back surfaces 33a, 34a than the coil surfaces 33b, 34b of the plate-shaped coils 33, 34. In this way, the plate-shaped magnets 22, 23, 24 and the plate-shaped coils 33, 34 are arranged in parallel in the thickness direction of the vibration actuator 10, so that the thickness dimension of the vibration actuator 10 can be reduced, and the vibration actuator 10 can be made thinner. In addition, various devices in which the vibration actuator 10 is incorporated can be made smaller and thinner. The thickness direction of the vibration actuator 10 is a direction perpendicular to the movable plate 21 and the fixed plate 31.

[0019] As shown in Figs. 4 and 6, the plate-shaped magnet 22 is disposed adjacent to the straight portion 40 of the plate-shaped coil 33, and the plate-shaped magnet 23 is disposed adjacent to the straight portion 41 of the plate-shaped coil 33. Similarly, the plate-shaped magnet 23 is disposed adjacent to the straight portion 44 of the plate-shaped coil 34, and the plate-shaped magnet 24 is disposed adjacent to the straight portion 45 of the plate-shaped coil 34. Furthermore, the side surface 22c of the plate-shaped magnet 22 and the side surface 40a of the straight portion 40 face each other, and the side surface 23c of the plate-shaped magnet 23 and the side surface 41a of the straight portion 41 face each other. Similarly, the side surface 23d of the plate-shaped magnet 23 and the side surface 44a of the straight portion 44 face each other, and the side surface 24c of the plate-shaped magnet 24 and the side surface 45a of the straight portion 45 face each other.

[0020] <Operation of vibration actuator> Figures 7 and 8 are diagrams showing the operating conditions of the vibration actuator 10. Also, Figures 7 and 8 show the same parts as those shown in Figure 4. Note that, in order to facilitate understanding of the operation of the vibration actuator 10, Figures 7 and 8 show the vibration actuator 10 enlarged in the thickness direction. Also, Figure 7 shows a state in which current is passed through the plate coils 33, 34 in the direction of arrow A1 in Figure 6, and Figure 8 shows a state in which current is passed through the plate coils 33, 34 in the direction of arrow A2 in Figure 6.

[0021] As shown in FIG. 7, the plate-shaped magnets 22, 24 arranged at both ends are magnetized so that the N pole appears on the magnet surfaces 22b, 24b, and the plate-shaped magnet 23 arranged in the center is magnetized so that the S pole appears on the magnet surface 23b. In this way, the plate-shaped magnets 22, 24 arranged at both ends and the plate-shaped magnet 23 arranged in the center are magnetized with opposite polarities. As a result, a magnetic field H1 directed from the fixed plate 31 toward the movable plate 21 is generated in the straight portion 40 of the plate-shaped coil 33, and a magnetic field H2 directed from the movable plate 21 toward the fixed plate 31 is generated in the straight portion 41 of the plate-shaped coil 33. Similarly, a magnetic field H3 directed from the movable plate 21 toward the fixed plate 31 is generated in the straight portion 44 of the plate-shaped coil 34, and a magnetic field H4 directed from the fixed plate 31 toward the movable plate 21 is generated in the straight portion 45 of the plate-shaped coil 34. The width dimension W1 of the plate-shaped magnet 23 arranged in the center is larger than the width dimension W2 of the plate-shaped magnets 22, 24 arranged at both ends. This makes it possible to increase the magnetic force of the plate-shaped magnet 23, and to generate sufficient magnetic fields H2, H3 in the two straight portions 41, .

[0022] When current flows through the straight portions 40, 41, 44, and 45 of the plate coils 33 and 34 as shown by the arrow A1 in Fig. 6 while the magnetic fields H1 to H4 are generated, as shown in Fig. 7, a Lorentz force F1a is generated in the straight portion 40, and a thrust F1b is generated in the plate magnet 22 in a direction toward the straight portion 40 due to the reaction. A Lorentz force F2a is generated in the straight portion 41, and a thrust F2b is generated in the plate magnet 23 in a direction away from the straight portion 41 due to the reaction. A Lorentz force F3a is generated in the straight portion 44, and a thrust F3b is generated in the plate magnet 23 in a direction toward the straight portion 44 due to the reaction. A Lorentz force F4a is generated in the straight portion 45, and a thrust F4b is generated in the plate magnet 24 in a direction away from the straight portion 45 due to the reaction. In this way, thrusts F1b, F2b, F3b, and F4b act on the plate-like magnets 22, 23, and 24 of the mover unit 20, so that the mover unit 20 is displaced in the direction of arrow X1 while deforming the rubber damper .

[0023] On the other hand, when a current flows through the straight portions 40, 41, 44, and 45 of the plate coils 33 and 34 as shown by the arrow A2 in Fig. 6, a Lorentz force F1c is generated in the straight portion 40, and a thrust F1d is generated in the plate magnet 22 in a direction away from the straight portion 40 due to the reaction, as shown in Fig. 8. A Lorentz force F2c is generated in the straight portion 41, and a thrust F2d is generated in the plate magnet 23 in a direction toward the straight portion 41 due to the reaction. A Lorentz force F3c is generated in the straight portion 44, and a thrust F3d is generated in the plate magnet 23 in a direction away from the straight portion 44 due to the reaction. A Lorentz force F4c is generated in the straight portion 45, and a thrust F4d is generated in the plate magnet 24 in a direction toward the straight portion 45 due to the reaction. In this way, thrusts F1d, F2d, F3d, and F4d act on the plate-like magnets 22, 23, and 24 of the mover unit 20, so that the mover unit 20 is displaced in the direction of arrow X2 while deforming the rubber damper .

[0024] That is, by switching the current flow direction of the plate coils 33, 34, the thrust acting on the mover unit 20 can be switched between the direction of the arrow X1 and the direction of the arrow X2. This allows the mover unit 20 to reciprocate at a predetermined stroke, and the vibration actuator 10 can be vibrated. By using this vibration actuator 10 to control the vibration pattern of the display 12, for example, a user who touches the display 12 can be given a tactile sensation such as a clicking sensation due to vibration. In the above description, both the movable plate 21 and the fixed plate 31 are made of a non-magnetic material, but this is not limited thereto, and either one of the movable plate 21 and the fixed plate 31 may be made of a non-magnetic material. That is, it is sufficient that at least one of the movable plate 21 and the fixed plate 31 is made of a non-magnetic material.

[0025] <Embodiments 2, 3, 4, 5> The vibration actuator 10 described above includes three plate-shaped magnets 22, 23, 24 and two plate-shaped coils 33, 34, but the number of plate-shaped magnets and plate-shaped coils may be changed. Here, Fig. 9A, Fig. 9B, Fig. 9C, and Fig. 9D are simplified diagrams showing vibration actuators 50, 60, 70, and 80 according to other embodiments of the present disclosure. Note that Fig. 9A, Fig. 9B, Fig. 9C, and Fig. 9D show only the plate-shaped magnets and plate-shaped coils, and do not show the movable plate 21, the fixed plate 31, the weight 25, and the like.

[0026] As shown in FIG. 9A, the vibration actuator 50 has one plate-shaped magnet 51 attached to the movable plate 21 and one plate-shaped coil 52 attached to the fixed plate 31. The plate-shaped magnet 51 is disposed adjacent to the straight portion 53 of the plate-shaped coil 52. Even when the vibration actuator 50 is configured with one plate-shaped magnet 51 and one plate-shaped coil 52, the vibration actuator 50 can be thinned by arranging the plate-shaped magnet 51 and the plate-shaped coil 52 in parallel in the thickness direction of the vibration actuator 50, as in the structure shown in FIG. 4. Even when the vibration actuator 50 is configured with one plate-shaped magnet 51 and one plate-shaped coil 52, a Lorentz force can be generated with respect to the straight portion 53, and the vibration actuator 50 can be vibrated.

[0027] As shown in FIG. 9B, the vibration actuator 60 has two plate-shaped magnets 61 and 62 attached to the movable plate 21 and one plate-shaped coil 63 attached to the fixed plate 31. The plate-shaped magnet 61 is disposed adjacent to the straight portion 64 of the plate-shaped coil 63, and the plate-shaped magnet 62 is disposed adjacent to the straight portion 65 of the plate-shaped coil 63. That is, the plate-shaped coil 63 is disposed between the plate-shaped magnet 61 and the plate-shaped magnet 62. In this way, even if the vibration actuator 60 is configured with two plate-shaped magnets 61 and 62 and one plate-shaped coil 63, the vibration actuator 60 can be made thinner by arranging the plate-shaped magnets 61 and 62 and the plate-shaped coil 63 in parallel in the thickness direction of the vibration actuator 60, as in the structure shown in FIG. 4. Even if the vibration actuator 60 is configured with two plate-shaped magnets 61 and 62 and one plate-shaped coil 63, a Lorentz force can be generated on the straight portions 64 and 65, and the vibration actuator 60 can be vibrated.

[0028] As shown in FIG. 9C, the vibration actuator 70 has one plate-shaped magnet 71 attached to the movable plate 21 and two plate-shaped coils 72, 73 attached to the fixed plate 31. The plate-shaped magnet 71 is disposed adjacent to the straight portion 74 of the plate-shaped coil 72 and adjacent to the straight portion 75 of the plate-shaped coil 73. That is, the plate-shaped magnet 71 is disposed between the plate-shaped coil 72 and the plate-shaped coil 73. Even if the vibration actuator 70 is configured with one plate-shaped magnet 71 and two plate-shaped coils 72, 73 in this way, the vibration actuator 70 can be made thinner by arranging the plate-shaped magnet 71 and the plate-shaped coils 72, 73 in parallel in the thickness direction of the vibration actuator 70, as in the structure shown in FIG. 4. Even if the vibration actuator 70 is configured with one plate-shaped magnet 71 and two plate-shaped coils 72, 73, a Lorentz force can be generated on the straight portions 74, 75, and the vibration actuator 70 can be vibrated.

[0029] As shown in FIG. 9D, the vibration actuator 80 has four plate-shaped magnets 81, 82, 83, and 84 attached to the movable plate 21, and three plate-shaped coils 85, 86, and 87 attached to the fixed plate 31. The four plate-shaped magnets 81, 82, 83, and 84 and the three plate-shaped coils 85, 86, and 87 are arranged in the following order: plate-shaped magnet 81, plate-shaped coil 85, plate-shaped magnet 82, plate-shaped coil 86, plate-shaped magnet 83, plate-shaped coil 87, and plate-shaped magnet 84. As a result, the plate-shaped magnet 81 is arranged adjacent to the straight portion 85a of the plate-shaped coil 85. The plate-shaped magnet 82 is arranged adjacent to both the straight portion 85b of the plate-shaped coil 85 and the straight portion 86a of the plate-shaped coil 86. The plate-shaped magnet 83 is arranged adjacent to both the straight portion 86b of the plate-shaped coil 86 and the straight portion 87a of the plate-shaped coil 87. Furthermore, the plate-shaped magnet 84 is disposed adjacent to the straight portion 87 b of the plate-shaped coil 87 .

[0030] In this way, even when the vibration actuator 80 is configured with four plate-shaped magnets 81, 82, 83, 84 and three plate-shaped coils 85, 86, 87, it is possible to achieve a thin vibration actuator 80 by arranging the plate-shaped magnets and plate-shaped coils in parallel in the thickness direction of the vibration actuator 80, similar to the structure shown in Fig. 4. Furthermore, even when the vibration actuator 80 is configured with four plate-shaped magnets 81, 82, 83, 84 and three plate-shaped coils 85, 86, 87, it is possible to generate a Lorentz force on the straight portions 85a, 85b, 86a, 86b, 87a, 87b, and it is possible to vibrate the vibration actuator 80.

[0031] 9D, when the numbers of plate-shaped magnets 81, 82, 83, 84 and plate-shaped coils 85, 86, 87 are increased, the excitation force of the vibration actuator 80 can be sufficiently ensured, so the plate-shaped magnets 81, 84 arranged at both ends may be reduced from the perspective of reducing the size of the vibration actuator 80. In other words, when the numbers of plate-shaped magnets 81, 82, 83, 84 and plate-shaped coils 85, 86, 87 are large, the effect on the decrease in the excitation force is limited, so it is possible to reduce the plate-shaped magnets 81, 84 arranged at both ends.

[0032] <Embodiment 6> In the examples shown in Figs. 2 to 5, the movable plate 21 and the fixed plate 31 are used without slits, but the present invention is not limited thereto, and slits for adjusting the magnetic field may be formed in the movable plate 21 and the fixed plate 31. Here, Fig. 10 is a perspective view showing a vibration actuator 90 according to another embodiment of the present disclosure, and Fig. 11 is an exploded perspective view showing the internal structure of the vibration actuator 90. Fig. 12 is a diagram showing the positional relationship between the slits 95, 96, 97, 98, and 99 formed in the movable plate 93 and the fixed plate 94, the plate-shaped magnets 22, 23, and 24, and the plate-shaped coils 33 and 34. Fig. 13 is a cross-sectional view showing the vibration actuator 90 along the line BB in Fig. 10. Note that Fig. 13 shows the same parts as those shown in Fig. 7, and shows the vibration actuator 90 enlarged in the thickness direction. In Figs. 10 to 13, the same reference numerals are used for the same parts and parts as those shown in Fig. 3, and the description thereof will be omitted.

[0033] As shown in Fig. 10 and Fig. 11, the vibration actuator 90 has a mover unit 91 including plate-shaped magnets 22, 23, and 24, and a stator unit 92 including plate-shaped coils 33 and 34. As shown in Fig. 11, the mover unit 91 has a movable plate (first plate) 93 made of a ferromagnetic material, three plate-shaped magnets 22, 23, and 24 attached to the movable plate 93, and a frame-shaped weight 25 attached to the movable plate 93. The stator unit 92 has a fixed plate (second plate) 94 made of a ferromagnetic material, a flexible printed circuit board 32 attached to the fixed plate 94, and two plate-shaped coils 33 and 34 attached to the flexible printed circuit board 32. As shown in Fig. 11 and Fig. 13, the movable plate 93 and the fixed plate 94 face each other.

[0034] The ferromagnetic material constituting the movable plate 93 and the fixed plate 94 may be, for example, ferritic stainless steel such as SUS430 or martensitic stainless steel such as SUS410. The ferromagnetic material is not limited to ferritic stainless steel or martensitic stainless steel, and the movable plate 93 and the fixed plate 94 may be made of iron, nickel, or the like.

[0035] 11 and 12, the movable plate 93 and the fixed plate 94 are provided with coil slits (coil openings) 95, 96 that open toward the hollow core portions 43, 47 of the plate-shaped coils 33, 34. The coil slits 95, 96 are not only open toward the hollow core portions 43, 47 of the plate-shaped coils 33, 34, but also extend to overlap the bent portions 42a, 42b, 46a, 46b of the plate-shaped coils 33, 34. The movable plate 93 and the fixed plate 94 are also provided with first magnet slits (magnet openings) 97 that open near both ends 23e, 23f of the plate-shaped magnet 23, that is, near both ends of the plate-shaped magnet 23 in the longitudinal direction. Furthermore, the movable plate 93 and the fixed plate 94 are provided with second magnet slits (magnet openings) 98, 99 that open near both ends 22d, 22e, 24d, 24e of the plate-shaped magnets 22, 24, i.e., near both longitudinal ends of the plate-shaped magnets 22, 24. The second magnet slits 98, 99 open not only near both ends 22d, 22e, 24d, 24e of the plate-shaped magnets 22, 24, but also near the side portions 22f, 24f of the plate-shaped magnets 22, 24.

[0036] In this way, by forming the coil slits 95, 96, the first magnet slit 97, and the second magnet slits 98, 99 in the movable plate 93 and the fixed plate 94, the magnetic circuit of the vibration actuator 90 can be improved. That is, as shown in FIG. 12, the second magnet slit 98 and the coil slit 95 can substantially surround the plate-shaped magnet 22 and the straight portion 40, and the magnetic flux from the plate-shaped magnet 22 to the straight portion 40 can be increased. Furthermore, the first magnet slit 97 and the coil slits 95, 96 can substantially surround the plate-shaped magnet 23 and the straight portions 41, 44, and the magnetic flux from the plate-shaped magnet 23 to the straight portions 41, 44 can be increased. Furthermore, the second magnet slit 99 and the coil slit 96 can substantially surround the plate-shaped magnet 24 and the straight portion 45, and the magnetic flux from the plate-shaped magnet 24 to the straight portion 45 can be increased.

[0037] As described above, since the magnetic circuit of the vibration actuator 90 can be improved, as shown in FIG. 13, the magnetic field H1x acting on the straight portion 40 can be made stronger than the magnetic field H1 shown in FIG. 7, and the magnetic field H2x acting on the straight portion 41 can be made stronger than the magnetic field H2 shown in FIG. 7. Similarly, the magnetic field H3x acting on the straight portion 44 can be made stronger than the magnetic field H3 shown in FIG. 7, and the magnetic field H4x acting on the straight portion 45 can be made stronger than the magnetic field H4 shown in FIG. 7. As a result, the Lorentz forces F1e, F2e, F3e, and F4e generated in the plate coils 33 and 34 can be made stronger than the Lorentz forces F1a, F2a, F3a, and F4a shown in FIG. 7. And the thrust forces F1f, F2f, F3f, and F4f generated in the plate magnets 22, 23, and 24 can be made stronger than the thrust forces F1b, F2b, F3b, and F4b shown in FIG. 7.

[0038] As described above, the magnetic circuit of the vibration actuator 90 can be improved by forming the slits 95, 96, 97, 98, and 99 in the movable plate 93 and the fixed plate 94. In other words, since the magnetic resistance of the slits 95 to 99 is higher than that of other parts, the magnetic flux is easily concentrated in the parts where the slits 95 to 99 are not formed, and as a result, the magnetic circuit can be improved. This makes it possible to increase the thrusts F1f, F2f, F3f, and F4f acting on the plate-shaped magnets 22, 23, and 24, and to increase the excitation force of the mover unit 91. In other words, from the viewpoint of making the vibration actuator 90 thinner, the plate-shaped magnets 22, 23, and 24 and the plate-shaped coils 33 and 34 are arranged in parallel in the thickness direction of the vibration actuator 90, but even with such an arrangement, the excitation force of the mover unit 91 can be sufficiently secured.

[0039] In the example shown in Figs. 10 to 13, the coil slits 95, 96, the first magnet slits 97, and the second magnet slits 98, 99 are formed in both the movable plate 93 and the fixed plate 94, but the present invention is not limited to this. In other words, the coil slits 95, 96, the first magnet slits 97, and the second magnet slits 98, 99 may be formed only in the movable plate 93 out of the movable plate 93 and the fixed plate 94. Also, the coil slits 95, 96, the first magnet slits 97, and the second magnet slits 98, 99 may be formed only in the fixed plate 94 out of the movable plate 93 and the fixed plate 94. In other words, it is sufficient that at least one of the movable plate 93 and the fixed plate 94 is made of a ferromagnetic material and is a plate in which the coil slits 95, 96, the first magnet slits 97, and the second magnet slits 98, 99 are formed.

[0040] <Embodiment 7> 10 to 13, coil slits 95, 96, first magnet slit 97, and second magnet slits 98, 99 are formed in movable plate 93 and fixed plate 94, but the present invention is not limited to this. Fig. 14A is a perspective view showing movable plate 100 and fixed plate 101 provided in a vibration actuator according to another embodiment of the present disclosure. Fig. 14B is a perspective view showing movable plate 110 and fixed plate 111 provided in a vibration actuator according to another embodiment of the present disclosure.

[0041] 14A, the movable plate 100 and the fixed plate 101 made of a ferromagnetic material are provided with coil slits (coil openings) 95, 96 that open into the air-core portions 43, 47 of the plate-shaped coils 33, 34. This makes it possible to improve the magnetic circuit of the vibration actuator, and to increase the excitation force of the vibration actuator.

[0042] Although the coil slits 95, 96 are formed in both the movable plate 100 and the fixed plate 101, the present invention is not limited to this. That is, the coil slits 95, 96 may be formed in either the movable plate 100 or the fixed plate 101. In other words, it is sufficient that at least one of the movable plate 100 and the fixed plate 101 is made of a ferromagnetic material and is a plate in which the coil slits 95, 96 are formed.

[0043] 14B, the movable plate 110 and the fixed plate 111 made of a ferromagnetic material are provided with a first magnet slit (magnet opening) 97 that opens near both ends 23e, 23f of the plate-shaped magnet 23, i.e., near both longitudinal ends of the plate-shaped magnet 23. The movable plate 110 and the fixed plate 111 are also provided with second magnet slits (magnet openings) 98, 99 that open near both ends 22d, 22e, 24d, 24e of the plate-shaped magnets 22, 24, i.e., near both longitudinal ends of the plate-shaped magnets 22, 24. This makes it possible to improve the magnetic circuit of the vibration actuator, and to increase the excitation force of the vibration actuator.

[0044] Although the first magnet slit 97 and the second magnet slits 98, 99 are formed in both the movable plate 110 and the fixed plate 111, the present invention is not limited to this. That is, the first magnet slit 97 and the second magnet slits 98, 99 may be formed in either the movable plate 110 or the fixed plate 111. That is, it is sufficient that at least one of the movable plate 110 and the fixed plate 111 is made of a ferromagnetic material and is a plate in which the first magnet slit 97 and the second magnet slits 98, 99 are formed.

[0045] <Embodiment 8> Fig. 15A is a perspective view showing a movable plate 120 and a fixed plate 121 provided in a vibration actuator according to another embodiment of the present disclosure, and Fig. 15B is an exploded perspective view of the movable plate 120 and the fixed plate 121 shown in Fig. 15A. Fig. 16 is a diagram showing the positional relationship between the auxiliary plates 123, 124, and 125, the plate magnets 22, 23, and 24, and the plate coils 33 and 34. In Fig. 16, the auxiliary plates 123, 124, and 125 are shown by dashed lines to facilitate understanding of the positional relationship.

[0046] 15A and 15B, the movable plate 120 and the fixed plate 121 include a plate body 122 made of a non-magnetic material, and three auxiliary plates 123, 124, and 125 made of a ferromagnetic material and attached to the plate body 122. As shown in Fig. 16, the auxiliary plate 123 is disposed overlapping the plate magnet 22 and the straight portion 40. In addition, the auxiliary plate 124 is disposed overlapping the plate magnet 23 and the straight portions 41 and 44, and the auxiliary plate 125 is disposed overlapping the plate magnet 24 and the straight portion 45.

[0047] In this way, by overlapping the auxiliary plates 123, 124, 125 made of a ferromagnetic material with the plate-shaped magnets 22, 23, 24 and the straight portions 40, 41, 44, 45, it is possible to increase the magnetic flux from the plate-shaped magnets 22, 23, 24 toward the straight portions 40, 41, 44, 45. This improves the magnetic circuit of the vibration actuator, thereby increasing the vibration force of the vibration actuator. Although the auxiliary plates 123, 124, 125 are attached to both the movable plate 120 and the fixed plate 121, this is not limiting. In other words, the auxiliary plates 123, 124, 125 may be attached to either the movable plate 120 or the fixed plate 121. That is, at least one of the movable plate 120 and the fixed plate 121 may be a plate constituted by the plate body 122 made of a non-magnetic material, and the auxiliary plates 123, 124, and 125 attached to the plate body 122 and made of a ferromagnetic material.

[0048] <Embodiment 9> 15A and 15B, three auxiliary plates 123, 124, and 125 are attached to the surface of the plate body 122, but this is not limited thereto, and the auxiliary plates 123, 124, and 125 may be attached to openings formed in the plate body. Here, Fig. 17A is a perspective view showing a movable plate 130 and a fixed plate 131 provided in a vibration actuator according to another embodiment of the present disclosure, and Fig. 17B is an exploded perspective view of the movable plate 130 and the fixed plate 131 shown in Fig. 17A.

[0049] As shown in Figures 17A and 17B, the movable plate 130 and the fixed plate 131 include a plate body 132 having three openings formed therein and made of a non-magnetic material, and three auxiliary plates 123, 124, and 125 made of a ferromagnetic material and attached to the openings 133, 134, and 135 of the plate body 132. In the auxiliary plates 123, 124, and 125 shown in Figures 17A and 17B, the auxiliary plate 123 is also arranged overlapping the plate-shaped magnet 22 and the straight portion 40, as shown in Figure 16 above. The auxiliary plate 124 is also arranged overlapping the plate-shaped magnet 23 and the straight portions 41 and 44, and the auxiliary plate 125 is arranged overlapping the plate-shaped magnet 24 and the straight portion 45.

[0050] In this way, by overlapping the auxiliary plates 123, 124, 125 made of a ferromagnetic material with the plate-shaped magnets 22, 23, 24 and the straight portions 40, 41, 44, 45, the magnetic flux from the plate-shaped magnets 22, 23, 24 toward the straight portions 40, 41, 44, 45 can be increased. This improves the magnetic circuit of the vibration actuator, thereby increasing the vibration force of the vibration actuator. Although the auxiliary plates 123, 124, 125 are attached to both the movable plate 130 and the fixed plate 131, this is not limiting. That is, the auxiliary plates 123, 124, 125 may be attached to either one of the movable plate 130 or the fixed plate 131. That is, it is sufficient that at least one of the movable plate 130 and the fixed plate 131 is a plate constituted by the plate main body 132 made of a nonmagnetic material and the auxiliary plates 123, 124, 125 attached to the plate main body 132 and made of a ferromagnetic material.

[0051] <Other embodiments> The present disclosure is not limited to the above embodiment, and various modifications are possible without departing from the gist of the present disclosure. In the example shown in Fig. 3 and Fig. 11, the plate-shaped magnets 22, 23, 24 are attached to the movable plates 21, 93, and the plate-shaped coils 33, 34 are attached to the fixed plates 31, 94, but the present disclosure is not limited to this, and the plate-shaped magnets 22, 23, 24 may be attached to the fixed plates 31, 94, and the plate-shaped coils 33, 34 may be attached to the movable plates 21, 93. In addition, the weight 25 is attached to the movable plates 21, 93, but the present disclosure is not limited to this, and if the movable plates 21, 93 and the plate-shaped magnets 22, 23, 24 have sufficient mass, the weight 25 may be removed from the movable plates 21, 93.

[0052] In the examples shown in Figs. 3 and 11, the rubber damper 48 is used as an elastic member connecting the movable plate 21, 93 and the fixed plate 31, 94, but this is not limited thereto, and a spring may be used as the elastic member. In the examples shown, the vibration actuator 10, 90 is provided with four rubber dampers 48, but this is not limited thereto, and the number of rubber dampers 48 of the vibration actuator 10, 90 may be set to three or less as long as the movable unit 20, 91 can be appropriately supported. Needless to say, five or more rubber dampers 48 may be provided in the vibration actuator 10, 90. In the examples shown, the rubber damper 48 is formed in a thin cylindrical shape, but this is not limited thereto, and the rubber damper 48 may be formed in another shape. For example, the rubber damper 48 may be formed in a thin cylindrical shape, or the rubber damper 48 may be formed in a thin rectangular column shape or rectangular tube shape.

[0053] In the examples shown in Fig. 7 and Fig. 13, the plate-shaped magnets 22, 24 arranged at both ends are magnetized so that the N pole appears on the magnet surfaces 22b, 24b, and the plate-shaped magnet 23 arranged at the center is magnetized so that the S pole appears on the magnet surface 23b, but this is not limited to this. In other words, the plate-shaped magnets 22, 24 arranged at both ends may be magnetized so that the S pole appears on the magnet surfaces 22b, 24b, and the plate-shaped magnet 23 arranged at the center may be magnetized so that the N pole appears on the magnet surface 23b. In the example shown in Fig. 5, the width dimension W1 of the plate-shaped magnet 23 arranged at the center is set larger than the width dimension W2 of the plate-shaped magnets 22, 24 arranged at both ends, but this is not limited to this. For example, the width dimension W1 of the plate-shaped magnet 23 arranged at the center and the width dimension W2 of the plate-shaped magnets 22, 24 arranged at both ends may be made to match each other.

[0054] In the above description, the fixed plate 31 constituting the vibration actuator 10 is attached to the display 12 or housing of the smartphone 11, but this is not limited to this. For example, the movable plate 21 constituting the vibration actuator 10 may be attached to the display 12 or housing of the smartphone 11.

[0055] The present technology can be configured as follows. [1] A vibration actuator comprising a first plate and a second plate opposed to the first plate, a plate-shaped magnet having a magnet back surface attached to the first plate and a magnet front surface located on the opposite side of the magnet back surface and facing the second plate; a plate-shaped coil including a coil back surface attached to the second plate and a coil front surface located on the opposite side of the coil back surface and facing the first plate; a resilient member having a first end attached to the first plate and a second end attached to the second plate; having The coil surface of the plate-shaped coil is located closer to the magnet back surface than the magnet surface of the plate-shaped magnet. Vibration actuator. [2] In the vibration actuator according to the above [1], The plate-shaped magnet is disposed adjacent to the straight portion of the plate-shaped coil. Vibration actuator. [3] In the vibration actuator according to the above [1] or [2], a weight attached to the first plate; Vibration actuator. [4] In the vibration actuator according to any one of the above [1] to [3], 2. The vibration actuator according to claim 1, A plurality of the plate-shaped magnets are attached to the first plate. Vibration actuator. [5] In the vibration actuator according to any one of the above [1] to [4], A plurality of the plate-shaped coils are attached to the second plate. Vibration actuator. [6] In the vibration actuator according to any one of the above [1] to [5], At least one of the first plate and the second plate is made of a non-magnetic material. Vibration actuator. [7] In the vibration actuator according to any one of the above [1] to [5], At least one of the first plate and the second plate is made of a ferromagnetic material and has a coil opening that opens into the hollow core portion of the plate-shaped coil. Vibration actuator. [8] In the vibration actuator according to any one of the above [1] to [5], At least one of the first plate and the second plate is made of a ferromagnetic material and has magnet openings that open near both ends of the plate-shaped magnet in the longitudinal direction. Vibration actuator. [9] In the vibration actuator according to any one of the above [1] to [5], At least one of the first plate and the second plate is A plate body made of a non-magnetic material; an auxiliary plate attached to the plate body and made of a ferromagnetic material; Equipped with The auxiliary plate is disposed so as to overlap the straight portion of the plate coil and the plate magnet. Vibration actuator. [Explanation of symbols]

[0056] 10... vibration actuator, 21... movable plate (first plate), 22, 23, 24... plate-shaped magnet, 22a, 23a, 24a... magnet back surface, 22b, 23b, 24b... magnet front surface, 22d, 22e, 23e, 23f, 24d, 24e... end portion, 25... weight, 31... fixed plate (second plate), 33, 34... plate-shaped coil, 33a, 34a... coil back surface, 33b, 34b... coil front surface, 40, 41... straight portion, 43... air core portion, 44, 45...straight portion, 47...air-core portion, 48...rubber damper (elastic member), 48a...first end portion, 48b...second end portion, 50...vibration actuator, 51...plate-shaped magnet, 52...plate-shaped coil, 53...straight portion, 60...vibration actuator, 61, 62...plate-shaped magnet, 63...plate-shaped coil, 64, 65...straight portion, 70...vibration actuator, 71...plate-shaped magnet, 72, 73...plate-shaped coil, 74, 75...straight portion, 80...vibration Moving actuator, 81, 82, 83, 84... plate-shaped magnets, 85, 86, 87... plate-shaped coils, 85a, 85b, 86a, 86b, 87a, 87b... straight portions, 90... vibration actuator, 93... moving plate (first plate), 94... fixed plate (second plate), 95, 96... coil slits (coil openings), 97... first magnet slits (magnet openings), 98, 99... second magnet slits (magnet openings), 1 00...movable plate (first plate), 101...fixed plate (second plate), 110...movable plate (first plate), 111...fixed plate (second plate), 120...movable plate (first plate), 121...fixed plate (second plate), 122...plate body, 123, 124, 125...auxiliary plates, 130...movable plate (first plate), 131...fixed plate (second plate), 132...plate body

Claims

1. A vibration actuator comprising a first plate and a second plate opposed to the first plate, a plate-shaped magnet including a magnet back surface attached to the first plate and a magnet front surface located on the opposite side of the magnet back surface and facing the second plate; a plate-shaped coil including a coil back surface attached to the second plate and a coil front surface located on the opposite side of the coil back surface and facing the first plate; a resilient member having a first end attached to the first plate and a second end attached to the second plate; having The coil surface of the plate-shaped coil is located closer to the magnet back surface than the magnet surface of the plate-shaped magnet. Vibration actuator.

2. 2. The vibration actuator according to claim 1, The plate-shaped magnet is disposed adjacent to the straight portion of the plate-shaped coil. Vibration actuator.

3. 2. The vibration actuator according to claim 1, a weight attached to the first plate; Vibration actuator.

4. 2. The vibration actuator according to claim 1, A plurality of the plate-shaped magnets are attached to the first plate. Vibration actuator.

5. 2. The vibration actuator according to claim 1, A plurality of the plate-shaped coils are attached to the second plate. Vibration actuator.

6. 2. The vibration actuator according to claim 1, At least one of the first plate and the second plate is made of a non-magnetic material. Vibration actuator.

7. 2. The vibration actuator according to claim 1, At least one of the first plate and the second plate is made of a ferromagnetic material and has a coil opening that opens into the air-core portion of the plate-shaped coil. Vibration actuator.

8. 2. The vibration actuator according to claim 1, At least one of the first plate and the second plate is made of a ferromagnetic material and has magnet openings that open near both ends of the plate-shaped magnet in the longitudinal direction. Vibration actuator.

9. 2. The vibration actuator according to claim 1, At least one of the first plate and the second plate is A plate body made of a non-magnetic material; an auxiliary plate attached to the plate body and made of a ferromagnetic material; Equipped with The auxiliary plate is disposed so as to overlap the straight portion of the plate coil and the plate magnet. Vibration actuator.

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