Vibration actuator and electrical instrument

Abstract

To provide a vibration actuator and an electrical instrument that are enhanced in robustness, thinned and reduced in manufacturing cost.SOLUTION: A vibration actuator comprises: a movable body which has a disk-like magnet, a pair of weight parts that are magnetic materials fixed to both sides of the magnet in an axial direction and a pair of spring connection parts provided at both ends in the axial direction; and a fixed body having a cylindrical body having an annular coil arranged on an outer periphery thereof, and storing the movable body so that the body can be vibrated to reciprocate in the axial by a pair of elastic support bodies connected to the pair of spring connection parts away from each other in the axial direction, and a case. The case has a pair of cylindrical cases with a bottom having case lid parts at one ends thereof and having case opening parts at the other ends thereof. Each of the pair of cylindrical cases with the bottom is made to overlap on the cylindrical body from both sides in the axial direction thereof and the case opening parts of the pair of cylindrical cases with the bottom are joined to each other to store the cylindrical body. The pair of cylindrical cases with the bottom is common members whose shapes are the same.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a vibration actuator and an electrical device equipped with the same. [Background technology]

[0002] Conventionally, electronic devices with a vibration function are equipped with a vibration actuator as a vibration generating source. By driving the vibration actuator and transmitting vibration to the user to make the user feel it, the electronic device can give the user a stimulus, notify the user of an incoming call, and improve the sense of operation and realism. The electronic device is mainly a handheld electric device including a portable game terminal, a controller (game pad) for a stationary game machine, a portable communication terminal such as a mobile phone or a smartphone, a portable information terminal such as a tablet PC, etc. In addition, a vibration actuator may also be implemented in a wearable terminal that is attached to clothing or an arm, etc.

[0003] As an example of a vibration actuator having a structure that can be miniaturized and mounted on a portable device, a vibration actuator used in a pager or the like is known, as shown in Patent Document 1.

[0004] This vibration actuator has a pair of elastic plates arranged to face each other and supported by the opening edges of a cylindrical frame. In addition, this vibration actuator has a yoke with a magnet attached fixed to a raised central portion of one of the pair of elastic plates, which has a spiral shape, and the yoke is supported within the frame.

[0005] The yoke and the magnet form a ring-shaped magnetic field generator, and the coil is attached to the other plate-like elastic body and disposed within the magnetic field of the magnetic field generator. Currents of different frequencies are applied to the coils through an oscillator circuit, causing the pair of plate-like elastic bodies to selectively resonate and generate vibrations, and the yoke vibrates within the frame in the direction of the center line of the frame.

[0006] In this vibration actuator, the distance between the magnet and the coil, and between the yoke and the coil, is made larger than the distance between the yoke and the inner peripheral wall of the frame. As a result, in the event of an external impact, the yoke hits the inner peripheral wall of the frame first, preventing the yoke or magnet from coming into contact with the coil, thereby preventing damage to the coil. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 3748637 Summary of the Invention [Problem to be solved by the invention]

[0008] Incidentally, a vibration actuator as a vibration generator is required to have a small design dimensional error, be thin, and ensure high output, and furthermore, it is required that the structure be able to withstand external shocks such as if it is dropped. In a configuration in which a plate-shaped elastic body is provided to close one opening of the frame body in a configuration in which a yoke is vibrated within a frame body as in Patent Document 1, when the vibration actuator is dropped and receives an external impact, the plate-shaped elastic body closing one opening of the frame body may collide with the yoke, which is a movable body, in addition to colliding with the outside. This causes a problem in that the plate-shaped elastic body itself is damaged, making it impossible to achieve stable vibration and high output.

[0009] The present invention has been made in view of the above-mentioned points, and has an object to provide a vibration actuator and an electrical device that are highly robust, thin, and inexpensive to manufacture. [Means for solving the problem]

[0010] One aspect of the vibration actuator of the present invention is a movable body including a disk-shaped magnet, a pair of weight portions that are magnetic bodies fixed to both sides of the magnet in an axial direction, and a pair of spring connection portions provided at both ends in the axial direction; a fixed body including a cylindrical body having an annular coil disposed on an outer periphery thereof and housing the movable body so as to be capable of reciprocating vibration in the axial direction by a pair of elastic support parts spaced apart in the axial direction and connected to the pair of spring connection parts; and a fixed body including a case. Equipped with the case includes a pair of bottomed cylindrical cases, each of which has a case lid at one end and a case opening at the other end, and the pair of bottomed cylindrical cases are each placed over the cylindrical body from both sides in the axial direction, and the case openings of the pair of bottomed cylindrical cases are joined together to accommodate the cylindrical body; The pair of bottomed cylindrical cases are configured to be common members having the same shape.

[0011] One aspect of the electrical device of the present invention is A handheld or wearable electrical device, The vibration actuator having the above-described configuration is mounted on the part that comes into contact with the user. Effect of the Invention

[0012] According to the present invention, it is possible to achieve high robustness, a thinner design, and reduced manufacturing costs. [Brief description of the drawings]

[0013] [Figure 1] 1 is an external perspective view of a vibration actuator according to an embodiment of the present invention; [Diagram 2] Cross-sectional view taken along line AA in Figure 1. [Diagram 3] 1 is an exploded perspective view showing a case and a drive unit of a vibration actuator according to an embodiment of the present invention. [Figure 4] FIG. 2 is an external perspective view of a drive unit. [Diagram 5] FIG. [Figure 6]FIG. 4 is an exploded perspective view showing a movable body and an elastic support part in the drive unit. [Figure 7] 13 is a diagram showing a state in which the outer yoke is removed from the coil assembly in fixing the drive unit. FIG. [Figure 8] FIG. [Figure 9] 3 is a diagram showing a schematic diagram of a magnetic circuit configuration of the vibration actuator. FIG. [Figure 10] 13 is a perspective view showing a modified example of the spacer in the vibration actuator. FIG. [Figure 11] 13 is a longitudinal sectional view of a vibration actuator including a modified spacer. FIG. [Figure 12] FIG. 12 is an enlarged view of a portion X in FIG. [Figure 13] 1 is a diagram showing an example of an electrical device in which a vibration actuator according to an embodiment of the present invention is mounted. [Figure 14] 1 is a diagram showing an example of an electrical device in which a vibration actuator according to an embodiment of the present invention is mounted. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0015] [Overall configuration of vibration actuator] Fig. 1 is an external perspective view of a vibration actuator according to an embodiment of the present invention, Fig. 2 is a cross-sectional view taken along line AA in Fig. 1, and Fig. 3 is an exploded perspective view showing a case and a drive unit of a vibration actuator according to an embodiment of the present invention. Note that the terms "upper" and "lower" in this embodiment are given for the sake of convenience to make it easier to understand, and refer to one side and the other side in the vibration direction of a movable body in the vibration actuator. In other words, when the vibration actuator is mounted on an electrical device (see Figs. 13 and 14), it does not matter if it is upside down or left to right.

[0016] The vibration actuator 1 is mounted as an electrical device as a vibration generating source in electronic devices such as portable game terminal devices (for example, the game controller GC shown in FIG. 13) and realizes the vibration function of the electronic device. Such electronic devices also include mobile devices such as smartphones (for example, the mobile terminal M shown in FIG. 14). The vibration actuator 1 is mounted in each device such as a portable game terminal device or a mobile device, and vibrates when driven to notify the user of an incoming call or to provide a sense of operation or realism.

[0017] 1, the vibration actuator 1 is a vibrating body formed into a cylindrical shape as a whole and has a case 10. The diameter of the case 10 is longer than the length in the axial direction (vibration direction).

[0018] 2 and 3, in this embodiment, the case 10 is a hollow cylindrical body formed by combining a first case piece (hereinafter also referred to as the "first case") 11-1 and a second case piece (hereinafter also referred to as the "second case") 11-2. A detailed description of the case 10 will be given later.

[0019] 2 and 3, the vibration actuator 1 is constructed by housing a drive unit 15 having a vibrating movable body 20 in a case 10. When the movable body 20 moves, the vibration actuator 1 itself functions as a vibrator. In this embodiment, the drive unit 15 is cylindrical corresponding to the case 10, and its central axis (not shown) is parallel to or coaxial with the central axis (not shown) of the case 10, which is also cylindrical. The vibration direction of the movable body 20 is a linear direction extending along the extension direction of the central axis of the cylindrical drive unit 15, including the F direction and the -F direction (see FIG. 9).

[0020] The vibration actuator 1 has a movable body 20 having a magnet 21, a first weight portion 23 and a second weight portion 25, a fixed body 40 having a coil (a pair of coils 61, 62), and plate-shaped elastic support portions 81, 82 that support the movable body 20 so that it can freely vibrate back and forth relative to the fixed body 40.

[0021] Fig. 4 is an external perspective view of the drive unit 15, specifically, Fig. 4 is a view of the drive unit 15 as seen from the terminal binding portion (which may be called the "terminal connection portion" together with the terminal pull-out portion) side. Fig. 5 is an exploded perspective view of the drive unit, showing the coil holding portion, the movable body, and the elastic support portion.

[0022] 2 to 5 includes a coil holding portion 42, an outer yoke 50, a movable body 20, and elastic support portions 81 and 82. The coil holding portion 42, together with the coils 61 and 62, constitutes a coil assembly that is a part of the fixed body, and the coil assembly, together with the outer yoke 50, constitutes a part of the fixed body.

[0023] The drive unit 15 supports the movable body 20 arranged in the coil holding portion 42 so that it can vibrate freely in a suspended state relative to the coil holding portion 42 via elastic support portions 81, 82 arranged opposite and spaced apart in the axial direction (vibration direction).

[0024] The drive unit 15 is connected to an external device via a terminal connecting portion (wire connection portion) 43 arranged on the outer circumferential surface thereof, and receives a supply of power from the external device.

[0025] <Movable body 20> As shown in Figs. 2 and 5, the movable body 20 is arranged inside the cylindrical coil holding portion 42 of the fixed body 40 with a gap therebetween in the circumferential direction. The movable body 20 is columnar, and the outer shapes of both ends (upper and lower ends) separated in the axial direction, i.e., the vibration direction, are formed smaller than the outer shape of the center portion. Both ends of the movable body 20 are connected to the inner periphery of the elastic support portions 81 and 82. The elastic support portions 81 and 82 cover both open ends (corresponding to the open end faces 427a and 428a) of the cylindrical coil holding portion 42. The movable body 20 is supported along the inner periphery 42a of the coil holding portion 42 so as to be reciprocatable in the axial direction (vibration direction).

[0026] FIG. 6 is an exploded perspective view showing a movable body and an elastic support portion in the drive unit.

[0027] As shown in Figures 2 and 5 to 6, the movable body 20 has a pair of weight portions (e.g., a first weight portion 23 and a second weight portion 25) and a pair of connection portions (a first spring connection portion 31 and a second spring connection portion 33) arranged on both sides of the magnet 21.

[0028] In this embodiment, the magnet 21 is disposed in the center of the movable body 20 in the vibration direction, that is, at the center of the movable body 20. On both sides of the vibration direction of the magnet 21 (the front surface 21a side and the back surface 21b side, which are the up-down direction in each drawing), the first weight portion 23, the second weight portion 25 and the spring connection portions 31 and 33 are disposed symmetrically with respect to the magnet 21. A first weight portion 23 and a second weight portion 25 are provided on both sides of the magnet 21 in the vibration direction, respectively, and a spring connection portion 31 is inserted into and joined to the first weight portion 23, and a connection portion 33 is inserted into and joined to the second weight portion 25.

[0029] <Magnet 21> 5 and 6, magnet 21 is a solid columnar (including plate-shaped) magnetized in the vibration direction. For example, magnet 21 has a magnetization direction that is the vibration direction, and front and back surfaces 21a and 21b that are spaced apart in the vibration direction have different polarities. The magnet 21 is formed, for example, in a cylindrical shape (which may also be called a flat disk shape or a disk shape) whose diameter (width) is longer than its length (height) in the vibration direction. The magnet 21 is, for example, a neodymium sintered magnet.

[0030] The magnet 21 is arranged so as to be positioned with a gap between it and the coil (a pair of coils 61, 62) held by the coil holding portion 42 (details will be described later) on the radial inside of the coil (a pair of coils 61, 62). Here, the "radial direction" also means a direction perpendicular to the axial direction (vibration direction) of the coil (a pair of coils 61, 62). In other words, the magnet 21 is arranged so as to face the center position in the vibration direction on the inner peripheral surface of the coil holding portion 42 on the radial outside. The pair of coils 61, 62 will also be referred to as "coils 61, 62" hereinafter.

[0031] This radial "spacing" is the spacing between the coils 61, 62 and the magnet 21 when the cylindrical main body portion 422 around which the coils 61, 62 are wound is positioned radially inside the coils 61, 62, between the coils 61, 62 and the magnet 21. Moreover, this interval is set to a distance that allows movement without contacting each other in the vibration direction of movable body 20. The "interval" in the embodiment refers to a predetermined distance between coil holding portion 42 (particularly cylindrical main body portion 422) and magnet 21 shown in FIG.

[0032] Magnet 21 may have a shape other than a solid columnar shape, such as a cylindrical shape or a plate shape, as long as it is disposed inside coils 61, 62 with two magnetized surfaces facing the extension direction (vibration direction) of the axes of coils 61, 62. In addition, it is preferable that the axial center of magnet 21 coincides with the axial center of movable body 20.

[0033] <First weight portion 23 and second weight portion 25> The first weight portion 23 and the second weight portion 25 each function as a weight that increases the vibration output of the movable body 20, and also function as a yoke.

[0034] The first weight portion 23 and the second weight portion 25 are formed in the same shape and are a common annular component having weight openings 232, 252, are arranged so as to sandwich the magnet 21 in the vibration direction, and are fixed to the front and back surfaces 21a, 21b of the magnet 21, respectively.

[0035] The first weight portion 23 and the second weight portion 25 are preferably made of a material with a high specific gravity (metal material). The first weight portion 23 and the second weight portion 25 are preferably made of, for example, tungsten (19.3 g / cm 3 The first weight portion 23 and the second weight portion 25 are formed as a ferromagnetic body by processing the material with a high specific gravity (for example, a specific gravity of 16 to 19 g / cm 3 It is preferable that the thickness is about 100 nm.

[0036] Since the first weight portion 23 and the second weight portion 25 are made of a material with a high specific gravity as a weight, the mass of the movable body 20 can be increased relatively easily even if the external dimensions of the movable body 20 are set in the design, etc.

[0037] The first weight portion 23 and the second weight portion 25 are made, for example, from tungsten that has been ferromagnetically treated, so that a single component can function as both a weight and a yoke, and by increasing the weight of the moving part, stronger vibrations can be obtained, improving the vibration characteristics.

[0038] In addition, since the first weight portion 23 and the second weight portion 25 are made of ferromagnetic material, together with the magnet 21, coil (a pair of coils 61, 62), and outer yoke 50 as a yoke, they form a magnetic circuit having an ideal magnetic path with little magnetic flux leakage and high magnetic efficiency.

[0039] The first weight portion 23 and the second weight portion 25 concentrate the magnetic flux of the magnet 21 and allow it to flow efficiently without leakage, effectively distributing the magnetic flux flowing between the magnet 21 and the coil (the pair of coils 61, 62).

[0040] The first weight portion 23 and the second weight portion 25 have large diameter portions 234, 254 having the same outer diameter and surface shape as the magnet 21, and small diameter portions 236, 256 having smaller outer diameters than the large diameter portions 234, 254.

[0041] The first weight portion 23 and the second weight portion 25 are fixed to the magnet 21 so that the outer peripheral surfaces of the large diameter portions 234, 254 are flush with the outer peripheral surface of the magnet 21, and the outer peripheral surfaces of the large diameter portions 234, 254, together with the outer peripheral surface of the magnet 21, form the outer peripheral surface of the movable body 20.

[0042] In the first weight portion 23 and the second weight portion 25, the small diameter portions 236, 256 are formed so as to be coaxially stacked on the large diameter portions 234, 254, and the small diameter portions 236, 256 form a shape in which the corners (outer peripheral portions) of both end portions that are separated in the vibration direction as the movable body 20 are cut out.

[0043] The shape of the corners (outer peripheral portions) of the upper end portion of the first weight portion 23 formed by the small diameter portion 236 ensures a deformation area for the elastic support portion 81, and ultimately a movable area for the movable body 20, so that the elastic support portion 81, which deforms when the movable body 20 moves, does not come into contact with the corners (outer peripheral portions) of the upper end portion of the first weight portion 23.

[0044] The shape of the corners (outer periphery) of the lower end portion of the small diameter portion 256 of the second weight portion 25 ensures a deformation area for the elastic support portion 82, and therefore a movable area for the movable body 20, so that the elastic support portion 82, which deforms when the movable body 20 moves, does not come into contact with the elastic support portion 82. As a result, when the movable body 20 vibrates, the movable body 20 is less likely to come into contact with the elastic support portions 81, 82, and can vibrate favorably. This makes it possible to ensure high vibration output while miniaturizing the vibration actuator 1.

[0045] The first weight portion 23 and the second weight portion 25 are positioned inside (radially inside) the coil (a pair of coils 61, 62) so as to face each of the coils (a pair of coils 61, 62) in a direction perpendicular to the axial direction of the coil (a pair of coils 61, 62).

[0046] It is preferable that the first weight portion 23 and the second weight portion 25 are each positioned inside (radially inside) the pair of coils 61, 62, in a direction perpendicular to the vibration direction, and facing the center of the vibration direction of the pair of coils 61, 62 when the movable body 20 is not vibrating.

[0047] Moreover, the first weight portion 23 and the second weight portion 25 are preferably arranged such that the height position of the upper surface of the large diameter portion 234 of the first weight portion 23 on the upper side of the magnet 21 is located lower (closer to the center) than the upper end position of the upper coil 61. In addition, the height position of the lower surface of the large diameter portion 254 of the second weight portion 25 on the lower side of the magnet 21 is preferably located higher (closer to the center) than the lower end position of the lower coil 62.

[0048] The first weight portion 23 and the second weight portion 25 may be fixed to the magnet 21 by being attracted to the magnet 21 by the large diameter portions 234, 254, or may be fixed to the magnet 21 by a thermosetting adhesive such as epoxy resin or an anaerobic adhesive.

[0049] The spring connecting parts 31, 33 (also referred to as the first spring connecting part 31 and the second spring connecting part 33) are inserted into the weight openings 232, 252. For example, the spring connecting parts 31, 33 may be fitted into the weight openings 232, 252, or may be joined after insertion.

[0050] The weight openings 232, 252 are provided so that the axes of the spring connecting parts 31, 33, in other words, the central axes of the elastic support parts 81, 82 described later, are positioned on the central axis of the movable body 20. The weight openings 232, 252 are formed with dimensions that fit in accordance with the outer shapes of the spring connecting parts 31, 33, but are not limited to this. The weight openings 232, 252 may be supported so as to be fixed by contacting the outer peripheral surfaces of the inserted spring connecting parts 31, 33 at three or four points and positioned on the axis of the movable body 20. The weight openings 232, 252 may be formed in a concave shape that does not penetrate in the axial direction and closes the magnet side that is fixed in the axial direction, and the spring connecting parts 31, 33 may be joined in this concave shape.

[0051] The mass of the first weight portion 23 and the second weight portion 25 can be adjusted according to the vibration output of the movable body 20 by changing the size (height dimension, which is the length in the vibration direction, and radial dimension perpendicular to the vibration direction) of the large diameter portions 234, 254 and the small diameter portions 236, 256 to a degree that does not interfere with the elastic support portions 81, 82 when the movable body 20 vibrates.

[0052] In the movable body 20, the outer peripheral surface 20a of the central portion (the outer peripheral surfaces of the magnet 21, first weight portion 23, and second weight portion 25) faces the inner peripheral surface 42a of the coil holding portion 42 at a predetermined distance inside.

[0053] In addition, the first weight portion 23 and the second weight portion 25 may have a function as a weight and a function as part of the magnetic circuit, as well as a function as the main body portion of the movable body 20 and a function of positioning and fixing the spring connection portions 31, 33 relative to the magnet 21.

[0054] <Spring connection parts 31, 33> The spring connection portions 31 and 33 connect the magnet 21, the first weight portion 23 and the second weight portion 25 to the elastic support portions 81 and .

[0055] The spring connection parts 31 and 33 are sleeves, and are provided at both ends in the vibration direction (both ends in the axial direction) of the movable body 20. The spring connection parts 31 and 33 constitute the ends of the movable body 20 that are located away from the magnet 21 on both sides in the vibration direction.

[0056] The spring connection parts 31, 33 are cylindrical bodies arranged along the central axis of the movable body 20, and are arranged so as to protrude along the axial direction from the center of each of the front and back surfaces 21a, 21b of the magnet 21, penetrating the first weight part 23 and the second weight part 25. The spring connection parts 31 and 33 are fixed to the first weight part 23 and the second weight part 25, respectively. The spring connection parts 31 and 33 may further be fixed to the magnet 21.

[0057] The spring connection portions 31, 33 have connection bodies 312, 332 provided on the other axial end side and inserted into the first weight portion 23 and the second weight portion 25, and support fixing portions 314, 334 provided on one end side and protruding from one end of the connection bodies 312, 332.

[0058] The outer diameter of the connection bodies 312, 332 is formed into a cylindrical shape having a diameter (the same diameter) that allows them to be inserted into the weight openings 232, 252 of this embodiment. The connection bodies 312, 332 may be fixed to both the first weight portion 23 and the second weight portion 25 by press-fitting them into both. The spring connection parts 31, 33 may be bonded to the first weight portion 23 and the second weight portion 25 using, for example, a thermosetting adhesive such as epoxy resin or an anaerobic adhesive.

[0059] The connection bodies 312, 332 may be joined by abutting against the magnet 21 at one end surface facing the magnet 21. The connection bodies 312, 332 are arranged so that the axis of the movable body 20 coincides with their central axes.

[0060] The support fixing parts 314, 334 join the movable body 20 to the elastic support parts 81, 82 via the connection bodies 312, 332 of the spring connection parts 31, 33.

[0061] The support fixing parts 314, 334 are protruding parts that protrude from the surface of one end side in the axial direction (vibration direction) of the connection main bodies 312, 332 and have an outer diameter smaller than the outer diameter of the connection main bodies 312, 332. Annular recesses 316, 336 are provided around these protruding parts and function as an adhesive reservoir, a welding reservoir, a part to be engaged during crimping, etc. in order to firmly join the support fixing parts 314, 334 to the inner periphery of the elastic support parts 81, 82.

[0062] Specifically, the support fixing part 314 constitutes one end of the movable body 20 in the vibration direction, i.e., the upper end of the movable body 20, and is joined to an inner circumferential part 802 which is the end on the inner diameter side of the upper leaf spring which is the elastic support part 81. On the other hand, the support fixing part 334 constitutes the other end of the movable body 20 in the vibration direction, i.e., the lower end of the movable body 20, and is joined to an inner circumferential part 802 which is the end on the inner diameter side of the lower leaf spring which is the elastic support part 82.

[0063] In a state where the support fixing parts 314, 334 are fitted and joined to the inner periphery parts 802, 802 of the elastic support parts 81, 82, the surface around the support fixing parts 314, 334, which is the surface on one end side of the connection main body 312, 332, is arranged to face the inner periphery parts 802, 802. Note that the connection main body 312, 332 may be joined to the elastic support parts 81, 82 joined to the support fixing parts 314, 334 at the part around the support fixing parts 314, 334 at one end. For example, the connection main body 312, 332 and the elastic support parts 81, 82 may be joined via an adhesive or by welding or the like. Also, the connection main body 312, 332 may be joined to the elastic support parts 81, 82 by sandwiching the elastic support parts 81, 82 between other members such as rivets. This allows the connection bodies 312, 332 and the inner circumferential portions 802, 802 to be reliably joined to each other, and allows the elastic support portions 81, 82 and the movable body 20 to be joined more reliably.

[0064] Furthermore, the elastic support parts 81, 82 and the support fixing parts 314, 334 may be connected by crimping or a combination of welding, bonding and crimping. The spring connecting parts 31, 33 are formed of, for example, a sintered copper material. The spring connecting parts 31, 33 may be made of a non-magnetic material or a magnetic material. If the spring connecting parts 31, 33 are made of a magnetic material, leakage magnetic flux can be prevented.

[0065] <Fixed body 40> 2, fixed body 40 has a pair of coils 61, 62, and accommodates movable body 20 having magnet 21 radially inside of the pair of coils 61, 62. Fixed body 40 supports movable body 20 via elastic support parts 81, 82 so as to be freely movable in the axial direction (which is the vibration direction and also the coil axial direction).

[0066] FIG. 7 is a diagram showing a state in which the outer yoke is removed from the coil assembly in the fixed body of the drive unit.

[0067] 2 to 5 and 7, the fixed body 40 includes a case 10, spacers (first spacer 13-1, second spacer 13-2), and coils (a pair of coils 61, 62), as well as a coil holding portion 42 that holds the coils 61, 62, and an outer yoke 50. The coil assembly including the coils 61, 62 and the coil holding portion 42 constitutes the drive unit 15 together with the outer yoke 50, the movable body 20, and the elastic support portions 81, 82.

[0068] The coil holding portion 42 is a cylindrical body formed of a resin such as a phenol resin, polybutylene terephthalate (PBT), etc. In the present embodiment, the coil holding portion 42 is formed of a material containing a phenol resin such as bakelite, which has high flame retardancy.

[0069] In addition, since the coil holding portion 42 is made of a material containing phenolic resin, the flame retardancy is improved, and the safety during operation can be improved even if the held coil (the pair of coils 61, 62) generates heat due to Joule heat when a current flows through the coil. In addition, the dimensional accuracy is improved, and the positional accuracy of the coil (the pair of coils 61, 62) is improved, so that the variation in vibration characteristics can be reduced.

[0070] As shown in Figures 2 and 7, the coil holding portion 42 has a cylindrical main body portion 422, flange portions 426-428 protruding radially from the outer peripheral surface of the cylindrical main body portion 422, a wiring portion 41 having a terminal pull-out portion (terminal connection portion) 46 and a connecting groove portion 47, and engaging protrusions 44, 45.

[0071] The coil holding portion 42 has coils 61, 62 arranged on the outer periphery of the cylindrical main body portion 422. The coil holding portion 42 is formed into a coil bobbin shape by the cylindrical main body portion 422 and flange portions 426-428.

[0072] The cylindrical main body 422 is located radially inside the pair of coils 61, 62, and has an inner circumferential surface 42a that faces the outer circumferential surface of the movable body 20 at a predetermined interval. This predetermined interval is a distance that allows the movable body 20 to move without coming into contact with the inner circumferential surface 42a when moving in the vibration direction.

[0073] The cylindrical main body 422 is positioned between the magnet 21 and the pair of coils 61, 62, thereby preventing contact between the magnet 21 and the pair of coils 61, 62. The cylindrical main body 422 guides the movable body 20 so that the movable body 20 can reciprocate along the inner circumferential surface 42a.

[0074] That is, cylindrical main body 422 functions as a protective wall that protects movable body 20 from collision with pair of coils 61, 62 when movable body 20 is driven.

[0075] The coil holding portion 42 has coils (a pair of coils 61, 62) disposed on coil attachment portions 42b, 42c (see FIGS. 2 and 7) provided on the outer circumferential side of the cylindrical main body portion 422. The coil attachment portions 42b, 42c (see FIGS. 2 and 7) are formed in a concave shape by the outer circumferential surface of the cylindrical main body portion 422 and flange portions 426-428 so as to open radially outward from the outer circumferential surface of the cylindrical main body portion 422 to the outer circumferential side. The pair of coils 61, 62 are disposed between flange portions (also referred to as "end flange portions") 427, 428 so as to sandwich a central flange portion (hereinafter also referred to as "central flange portion") 426 in the vibration direction.

[0076] The coils 61 and 62 are positioned side by side in the coil axial direction so as to surround the outer circumferential surfaces of the first weight portion 23 and the second weight portion 25 of the movable body 20 .

[0077] The central flange portion 426 is provided in an annular shape protruding radially outward from the outer circumferential surface of the cylindrical main body portion 422 .

[0078] The diameter of the central flange portion 426 excluding the terminal lead-out portion 46, i.e., the diameter of the outer circumferential portion 426a, is shorter than the maximum diameter of the other flange portions (end flange portions 427, 428). As a result, a concave portion 420 is formed in the outer circumferential surface of the coil holding portion 42, located in the central portion in the vibration direction, and at the open ends of the coil attachment portions 42b, 42c (see FIGS. 2 and 7).

[0079] As a result, the outer yoke 50 fits into the recessed portion 420, and the outer yoke 50 covers the coil mounting portions 42b, 42c on which the coils 61, 62 are arranged, with its outer surface positioned flush with the outer surfaces of the end flange portions 427, 428.

[0080] The wiring part 41 is provided on a part of the outer periphery of the central flange part 426, and is used for wiring the windings that constitute the coils 61, 62. The wiring part 41 is disposed in the central part in the axial direction (vibration direction) on the outer periphery of the drive unit 15 or the coil assembly.

[0081] The wiring portion 41 projects outward so as to pass through the outer yoke 50, and processes the ends (winding 63) of the coils 61, 62 into a state connectable to an external device via the terminal pull-out portion 46 having a flat tip surface, and the connecting groove portion 47 guides the coil winding 64. As a result, the coil winding (for example, winding 64) is wired so that the coil holding portion 42 appropriately holds the coils 61, 62.

[0082] The terminal pull-out portion 46 has a terminal entangling portion 43 protruding from the flat surface. As shown in Fig. 7, the terminal entangling portion 43 entangles the winding 63 at the end of the winding that connects the pair of coils 61, 62, and functions as a connector connecting portion that connects to an external device. The terminal entangling portion 43 connects the pair of coils 61, 62 to an external device (for example, a power supply unit such as a drive control unit), and enables power to be supplied from the external device to the pair of coils 61, 62. The terminal entangling portion 43 is conductive and has a rod-shaped body for entangling the coil windings.

[0083] The terminal winding portion 43 has a base end press-fitted into the terminal pull-out portion 46 protruding from the outer periphery of the coil holding portion 42. The terminal winding portion 43 is connected to the winding 63 at the end of the winding that constitutes the coils 61, 62, and this connection portion is securely joined by a ferrule 432 formed by soldering.

[0084] Terminal pull-out portion 46 protrudes from the outer circumferential surface of central flange portion 426, and is provided at central flange portion 426 with a predetermined radial length, a thickness in the vibration direction, and a width along the circumferential direction, thereby ensuring a press-fitting margin for terminal entangling portion 43. The horizontal side of the tip surface of terminal pull-out portion 46 is parallel to a tangent to the outer periphery of central flange portion 426, and here, both ends of coils 61, 62 connected to terminal entangling portion 43 protrude from the tip surface of terminal pull-out portion 46.

[0085] Since the terminal pull-out portion 46 has a sufficient press-fitting margin for the terminal tying portion 43, the terminal tying portion 43 can be firmly held, and the terminal tying portion 43 can be stably fixed when assembled to the coil holding portion 42.

[0086] Terminal pull-out portion 46 pulls out the ends of the windings forming the coils (pair of coils 61, 62) to the outside of vibration actuator 1 via terminal fastening portion 43 for connection to a power supply. Terminal pull-out portion 46 passes through outer yoke 50, exposing terminal fastening portion 43 to the outside of outer yoke 50 and therefore to the outside of case 10.

[0087] Since the terminal lashing portion 43 is provided on the terminal pull-out portion 46, even if the outer yoke 50 comes into contact with the terminal lashing portion 43 and applies a load to the outer yoke 50 when the terminal lashing portion 46 is inserted through the outer yoke 50, the load can be received by the terminal pull-out portion 46. This prevents the load applied when the outer yoke 50 is attached from being applied to the terminal lashing portion 43, prevents deformation of the terminal lashing portion 43 due to the load, and enables the vibration actuator to be manufactured stably.

[0088] A coil winding 64 that connects the coils (a pair of coils 61, 62) is inserted into the communication groove portion 47. In the communication groove portion 47 of the present embodiment, the winding directions of the coil windings that form the coils 61 and 62 are reversed above and below the communication groove portion 47.

[0089] The communication groove portion 47 is formed so as to open radially outward at the outer periphery of the central flange portion 426 and to penetrate along the vibration direction. Specifically, the communication groove portion 47 has a bottom wall portion 47a forming a groove-shaped bottom, and a side wall portion (one side wall portion) 47b of the bottom wall portion 47a that is far from the terminal binding portion 43.

[0090] The communication groove 47 communicates the coil mounting parts 42b and 42c in the vibration direction on the radial inside of the outer yoke 50 even when the central flange part 426 is covered by the outer yoke 50. The communication groove 47 is disposed close to or adjacent to the terminal pull-out part 46. The notch-shaped part has a function of locking the winding so that it does not come off when one of the coils 61 and 62 is wound and disposed, and then the other is wound and disposed in the reversed winding direction. The communication groove 47 of this embodiment is formed in a U-shape in a plan view with both side walls standing on both ends separated in the circumferential direction with the bottom wall part 47a as the bottom surface. Therefore, when the pair of coils 61 and 62 are disposed by winding the coil winding around the coil mounting parts 42b and 42c in the up-down inverted direction, the coil winding 64 is reliably engaged with and retained in the communication groove part 47 so as not to come off from the communication groove part 47.

[0091] In addition, the wiring portion 41 has a coil guide portion 412 in the central flange portion 426 that guides the coil winding 63 from the terminal winding portion 43 to the position of the first turn (e.g., a corner) in the coil winding portion (one of the coil mounting portions 42b, 42c) of the coil holding portion 42 (see Figure 7).

[0092] The coil guide portion 412 is formed in a stepped shape on at least one of the upper and lower surfaces (surfaces separated in the vibration direction) of the central flange portion 426, at the upper surface portion of the connecting groove portion 47 adjacent to one side of the terminal pull-out portion 46 in the circumferential direction, and at the lower surface portion of the terminal pull-out portion 46.

[0093] The coil guide portion 412 is an inclined portion formed by steps on the upper and lower surfaces (surfaces in the vibration direction) of the central flange portion 426, and guides the coil winding from the terminal winding portion 43 so that it can be pulled in to the bottom side of the coil mounting portions 42b, 42c, that is, the outer peripheral surface side of the cylindrical main body portion 422.

[0094] End flange portions 427 , 428 are provided at both ends of cylindrical main body portion 422 that are spaced apart in the axial direction, and constitute the upper and lower ends of coil holding portion 42 .

[0095] End flanges 427, 428 (collectively referred to as "end flanges") are provided so as to protrude radially from the outer periphery of cylindrical main body 422 to both ends in the vibration direction. The outer periphery of each of end flanges 427, 428 has a portion with the same diameter as outer periphery 426a of central flange 426. These same diameter portions form recessed portion 420 including recessed coil mounting portions 42b, 42c, and this same diameter portion abuts against the inner periphery of outer yoke 50.

[0096] By disposing the outer yoke 50 in this recessed portion 420, the outer yoke 50 is positioned at a position surrounding the pair of coils 61, 62. Furthermore, the outer yoke 50 is stably fixed to the coil holding portion 42 by abutting the outer circumferential portion 426a and the same diameter portions of the end flange portions 427, 428. As a result, even if the height dimension (length in the vibration direction) of the outer yoke 50 becomes large, it can be stably fixed by an installation method corresponding to that.

[0097] End flange portions 427, 428 are formed in a cylindrical shape that opens in a direction (vertical direction in this embodiment) away from central flange portion 426. Elastic support portions 81, 82 are fixed to end flange portions 427, 428 at the ends on the opening side, i.e., the upper and lower ends.

[0098] The engaging protrusions 44, 45 are protrusions protruding in the vibration direction (up and down direction) at the upper and lower ends of the coil holding portion 42, i.e., at the upper and lower opening end faces (also referred to as the "upper end face" and the "lower end face") 427a, 428a of the annular end flange portions 427, 428, respectively.

[0099] 2 and 3, the engaging protrusions 44, 45, together with the first spacer 13-1 and the second spacer 13-2, sandwich the elastic support parts 81, 82 in the first case 11-1 and the second case 11-2, and engage with the engaging recesses 134 of the first spacer 13-1 and the second spacer 13-2. The engaging protrusions 44, 45 engage with the engaging recesses 134 to position the first case 11-1, the second case 11-2, and the coil holding part 42 in the radial direction and the vibration direction. In addition, together with the first spacer 13-1 and the second spacer 13-2, the engaging protrusions 44, 45 also position the elastic support parts 81, 82 sandwiched between them in the radial direction.

[0100] <Coils 61 and 62> In the vibration actuator 1, the pair of coils 61, 62, together with the magnet 21, the first weight portion 23 and the second weight portion 25, constitute a magnetic circuit used to generate a driving source, with the axial direction of the pair of coils 61, 62 (the magnetization direction of the magnet 21) being the vibration direction.

[0101] The pair of coils 61, 62 are energized when driven (when vibrating) and constitute a voice coil motor together with the magnet 21. Although a pair of coils 61, 62 is used in this embodiment, one coil or three or more coils may be used as long as they form a magnetic circuit that is driven in the same manner, but it is preferable to use an even number of coils so that they are symmetrical in the vibration direction.

[0102] The pair of coils 61, 62 are disposed in positions symmetrical about the magnet 21 in the vibration direction with respect to the movable body 20 having the magnet 21, the first weight portion 23, the second weight portion 25, etc. It is preferable that the center position of the length of the coils in the vibration direction, that is, the center position of the length between the upper end of the coil 61 and the lower end of the coil 62, is the same position (including approximately the same position) in the vibration direction as the center position of the length of the movable body 20 (particularly the magnet 21) in the vibration direction.

[0103] In this embodiment, the pair of coils 61, 62 is configured by winding a single coil in opposite directions, and when energized, current flows in opposite directions through the coils 61, 62. The ends of each of the pair of coils 61, 62, i.e., both ends of the windings of the coils constituting the pair of coils 61, 62, are wound and connected to the terminal winding portion 43 of the flange portion 426.

[0104] The coils (a pair of coils 61, 62) are connected to a power supply unit (for example, the drive control unit 203 shown in Figs. 13 and 14) via the terminal fastening unit 43. For example, each end of the coils (a pair of coils 61, 62) is connected to an AC supply unit via the terminal fastening unit 43, and an AC power source (AC voltage) is supplied from the AC supply unit to the coils (a pair of coils 61, 62). This allows the coils (a pair of coils 61, 62) to generate a thrust between the magnet and the coils (a pair of coils 61, 62) that can move toward and away from each other in the axial direction. The coils 61, 62 can be assembled without using a self-bonding wire, which reduces the cost of the coils (a pair of coils 61, 62) themselves, and ultimately reduces the cost of the entire vibration actuator.

[0105] <Outer yoke 50> 2 to 5 and 7, the outer yoke 50 is a cylindrical magnetic body that surrounds the outer circumferential surface of the coil holding portion 42 and is disposed in a position that covers the pair of coils 61, 62 from the radial outside. As described above, the outer yoke 50 constitutes a magnetic circuit on the fixed body side together with the pair of coils 61, 62 and constitutes a magnetic circuit on the movable body side, that is, a magnetic circuit together with the magnet 21, the first weight portion 23 and the second weight portion 25. The outer yoke 50 prevents leakage of magnetic flux from the magnetic circuit to the outside of the vibration actuator 1.

[0106] The outer yoke 50 increases the thrust constant in the magnetic circuit to improve the electromagnetic conversion efficiency. The outer yoke 50 is arranged so that the center of the length of the outer yoke 50 in the vibration direction is at the same height as the center of the vibration direction of the magnet 21 arranged inside. The shielding effect of the outer yoke 50 can reduce leakage magnetic flux to the outside of the vibration actuator.

[0107] Both ends of the outer yoke 50 that are separated in the vibration direction are preferably configured to a length that does not cover both ends of the movable range in the vibration direction of the laminated body formed by stacking the magnets 21, the first weight portion 23, and the second weight portion 25, regardless of whether the movable body 20 is vibrating or not. The outer yoke 50 has a yoke body 51 and a plurality of openings (first opening 53, second opening 55) that are provided at the same position in the vibration direction of the yoke body 51 and distributed in the circumferential direction.

[0108] The yoke body 51 is formed into a cylindrical shape and is made of, for example, SECC (electro-galvanized steel sheet) which has excellent weldability and corrosion resistance.

[0109] Yoke body 51 is flexible and has, for example, a slit parallel to the axial direction in a part of the peripheral wall. Yoke body 51 is formed into a C-shaped cylinder in a planar cross section. When yoke body 51 is attached to the outer periphery of coil holding part 42, ends 52 constituting the slit portion are widened and coil holding part 42 is disposed inside yoke body 51. Next, the deformation of yoke body 51 is restored and yoke body 51 is fitted into recessed portion 420 on the outer periphery of coil holding part 42, whereby yoke body 51 is fitted onto coil holding part 42.

[0110] The multiple openings 53, 55 are all provided in the yoke body 51 at positions that are equally spaced apart in the circumferential direction around the axis of the outer yoke 50. The multiple openings 53, 55 are also provided at the center of the vibration direction, which is the height direction, of the yoke body 51. The multiple openings 53, 55 open in the yoke body 51, for example, at positions that face each other around the axis of the outer yoke 50.

[0111] In this embodiment, the multiple openings 53, 55 are formed in the yoke body 51 in the circumferential direction by parallel sides that are spaced apart in the circumferential direction, and in the vibration direction are formed in a rectangular shape separated by upper and lower sides that are spaced apart in the vibration direction and are symmetrical about the center point of the vibration direction.

[0112] The multiple openings 53, 55 include a first opening 53 for passing wiring connecting an external device to coils 61, 62, and a second opening 55 provided at a predetermined position based on the position of first opening 53. Opening 53 is provided in the center of the slit portion of yoke body 51 so as to extend in the circumferential direction.

[0113] Terminal lead-out portion 46 is inserted into opening 53. As a result, terminal entanglement portion (wiring) 43 connected to coils 61, 62 passes through opening 53, and terminal entanglement portion (wiring) 43 is disposed in an exposed state protruding outside outer yoke 50 so as to be connectable to an external device.

[0114] Furthermore, the opening 53 has a function of preventing rotation of the outer yoke 50 in the circumferential direction relative to the coil holding portion 42 by fitting into the terminal lead-out portion 46 .

[0115] Opening 53 has cutout portions 533 formed on diagonally arranged edges of left and right sides that separate opening 53, the cutout portions 533 being shaped to widen a part of opening 53 in the circumferential direction. That is, opening 53 has a cutout shape in which the positions of the edges extending along the vibration direction are shifted in the circumferential direction.

[0116] An end of the winding connected to the terminal entangling portion 43 is wired in the cutout portion 533. When the outer yoke 50 is fitted into the recessed portion 420 of the coil holding portion 42 and the terminal pull-out portion 46 is positioned in the opening 53, the winding connecting the terminal entangling portion 43 of the terminal pull-out portion 46 and the coils 61, 62 on the inside of the outer yoke 50 is wired in the cutout portion 533. This allows the outer yoke 50 to be suitably attached to the coil holding portion 42 without the coil winding getting in the way.

[0117] In outer yoke 50, left and right side portions that divide opening 53 in the circumferential direction may be formed to sandwich terminal lead-out portion 46. In this case, the protruding side portions adjacent to cutout portion 533 can press terminal lead-out portion 46 from both sides in the circumferential direction to hold terminal lead-out portion 46. This allows outer yoke 50 to be securely attached to coil holding portion 42 with terminal lead-out portion 46 being sandwiched in the circumferential direction.

[0118] Moreover, the opening 53 is divided into two regions separated in the vibration direction by the terminal pull-out portion 46, and a belt-shaped open region extending in the circumferential direction and communicating with the cutout portion 533 is formed on both sides (upper and lower) in the vibration direction of the terminal pull-out portion 46. In the belt-shaped region including the cutout portion 533, a winding connecting the terminal binding portion 43 and the coil attachment portions 42b, 42c is suitably arranged.

[0119] Opening (second opening) 55 is provided at a position facing opening 53 with respect to the radial center. Opening 55 is formed, for example, in a position facing opening 53 in yoke body 51. Opening 55 has substantially the same shape as opening 53, and is formed in a rectangular shape extending in the circumferential direction and partitioned by top, bottom, left and right sides.

[0120] The widths in the vibration direction of upper and lower side portions 55a, 55b which partition opening 55 are formed to be substantially the same as the widths in the vibration direction of the upper and lower side portions of opening 53.

[0121] The openings 53 and 55 form a magnetic path in the magnetic circuit that is symmetrical about the axis, ensuring a balance of the generated magnetism. That is, the openings 53 and 55 allow the movable body 20 and the fixed body 40 to attract each other equally in the vibration direction and in a direction perpendicular to the vibration direction (radial direction), that is, in the up, down, left and right directions. As a result, the movable body 20 vibrates in a state where they are attracted to each other equally in the radial direction relative to the fixed body, and the vibration actuator 1 is well-balanced, and the imbalance of the magnetic attraction force in the magnetic circuit and leakage magnetic flux can be minimized.

[0122] In this embodiment, each of the upper and lower side portions that separate opening 53 is divided in the circumferential direction by a slit sandwiched between end portions 52, which differs from a configuration in which the upper and lower side portions have no slits. However, the division of opening 53 into the upper and lower side portions has a function similar to that of upper and lower side portions without slits, since the distance between end portions 52 that face each other in the circumferential direction via the cutout is short, and thus provides the same effect in terms of the magnetic circuit.

[0123] In this embodiment, the openings 53, 55 are configured to be provided at two locations facing each other in the center of the outer yoke 50 in the vertical direction (vibration direction), but two or more openings may be provided as long as they are spaced equally apart around the axis of the outer yoke 50.

[0124] <Elastic support parts 81, 82> As shown in FIGS. 2 to 6, the elastic support portions 81, 82 support the movable body 20 so as to be capable of reciprocating movement relative to the fixed body 40 in the vibration direction.

[0125] The elastic support parts 81 and 82 sandwich the movable body 20 in the vibration direction of the movable body 20, and are installed across both the movable body 20 and the fixed body 40 so as to intersect with the vibration direction.

[0126] In this embodiment, as shown in Figures 2 to 6, the elastic support members 81 and 82 are attached parallel to each other across both ends (upper and lower ends) of the coil holding portion 42 that are spaced apart in the vibration direction and both ends of the movable body.

[0127] The elastic support parts 81 and 82 are each a plurality of flat leaf springs, each formed into a spiral shape in the shape of a disk. The elastic support parts 81 and 82 each have a shape in which an annular inner circumferential part 802, which is the inner spring end, and an annular outer circumferential part 806, which is the outer spring end, are joined by a deformation arm 804 that is an elastically deformable arc-shaped in plan view.

[0128] The deforming arm 804 is disposed in a spiral shape connecting the inner peripheral portion 802 and the outer peripheral portion 806, and deformation of the deforming arm 804 causes the inner peripheral portion 802 and the outer peripheral portion 806 to be relatively displaced in the axial direction.

[0129] The elastic support portions 81 and 82 support the movable body 20 so as to be movable in the axial direction (vibration direction) without contacting the fixed body 40.

[0130] The inner periphery 802 has a connection hole 802a disposed at the center of the elastic support parts 81 and 82. Both ends of the movable body 20 that are separated in the vibration direction (support fixing parts 314 and 334 of the spring connection parts 31 and 33) are fitted and connected to this connection hole 802a.

[0131] On the other hand, the outer peripheral portion 806 is attached to the upper and lower ends of the coil holding portion 42, i.e., the opening end faces 427a, 428a of the end flange portions 427, 428, in a state where it is sandwiched between the first spacer 13-1 and the second spacer 13-2. The outer peripheral portion 806 is fixed in a state where the engaging protrusions 44, 45 are engaged with the positioning groove portion 808 and positioned. The end flanges 427, 428 may be fixed to the opening end faces 427a, 428a by being adhered to the opening end faces 427a, 428a with an adhesive or the like.

[0132] The leaf springs serving as elastic support members 81, 82 may be made of any material that is elastically deformable, and may be made by sheet metal processing using stainless steel plate, phosphor bronze, etc. In this embodiment, elastic support members 81, 82 are thin, flat, disc-shaped spiral springs made of phosphor bronze, which has high workability, excellent corrosion resistance, tensile strength, and wear resistance.

[0133] In this embodiment, the multiple elastic support members 81, 82 are joined to the coil holding member 42 and the movable body 20 with their spiral directions oriented in the same direction, and can move smoothly along the vibration direction, i.e., deform, even if the amount of movement of the movable body 20 increases.

[0134] Further, outer periphery 806 of elastic support part 81 is positioned and fixed on an annular opening end face 427a of end flange part 427 at a position avoiding engaging protrusion 44. On the other hand, outer periphery 806 of elastic support part 82 is positioned and fixed on annular opening end face 428a of end flange part 428 at a position avoiding engaging protrusion 45.

[0135] In this manner, the elastic support portions 81, 82 are clamped between the opening end faces 427a, 428a of the upper and lower opening edge portions of the coil holding portion 42, the first spacer 13-1, and the second spacer 13-2 in a state arranged in a direction perpendicular to the vibration direction.

[0136] In addition, the elastic support portions 81, 82 are attached to the coil holding portion 42 and the movable body 20 accommodated inside the coil holding portion 42 so as to close the upper and lower openings of the coil holding portion 42 around which a pair of coils 61, 62 are wound on the outer circumferential side.

[0137] <Case 10> FIG. 8 is an exploded perspective view of the case.

[0138] The case 10 has a first case 11-1 and a second case 11-2 shown in Figs. 1 to 3 and 8, and the first case 11-1 and the second case 11-2 have the same shape and are made of the same material, and are common members. The first case 11-1 and the second case 11-2 are formed in the same cylindrical shape with a bottom. The case openings 111-1 and 111-2 of the peripheral walls 114-1 and 114-2 have cutouts 116-1 and 116-2 at a part of the opening edge of the case openings 111-1 and 111-2. The cutouts 116-1 and 116-2 are arranged so that the wiring part 41 is exposed to the outside when the drive unit 15 is accommodated in the case 10 together with the spacers 13-1 and 13-2. That is, the cutouts 116-1 and 116-2 are joined together to form a cutout opening, and the terminal connection part (the wiring part 41) of the cylindrical body is inserted into the cutout opening. The first case 11-1 and the second case 11-2 are joined together, for example, by welding.

[0139] The first case 11-1 and the second case 11-2 have peripheral walls 114-1 and 114-2 rising from disk-shaped case lids 112-1 and 112-2, and the internal corners do not have steps or the like for arranging the drive unit 15. The case lids 112-1 and 112-2 also function as case bottoms instead of case lids depending on the arrangement positions of the first case 11-1 and the second case 11-2. For convenience, the bottoms of the bottomed cylindrical first case 11-1 and second case 11-2 are referred to as case lids 112-1 and 112-2 and described below, but they also function as case bottoms.

[0140] The first case 11-1 and the second case 11-2 may be made of a non-magnetic material or a magnetic material, and for example, when made of a magnetic material, they function as a magnetic shield. The first case 11-1 and the second case 11-2 are, for example, metal cases that are magnetic bodies formed by drawing a metal sheet such as SUS.

[0141] Case lids 112-1, 112-2 of first case 11-1 and second case 11-2 are formed of thin plate-like bodies and define the movable range of movable body 20 in drive unit 15 inside case 10. Note that the back surfaces of first case 11-1 and second case 11-2 may each be shaped so that their thickness decreases toward the center (the axis).

[0142] The first case 11-1 and the second case 11-2 have positioning holes 118-1, 118-2, into which a jig can be inserted to position the first case 11-1 and the second case 11-2 while preventing them from rotating when assembling the vibration actuator 1. This allows one or both of the first case 11-1 and the second case 11-2 to be positioned when inserting the drive unit 15 easily into the case 10, and allows the two to be easily assembled after the drive unit 15 is inserted inside. When the drive unit 15 is housed in the first case 11-1 and the second case 11-2, the cutouts 116-1, 116-2 are used to allow the windings of the coils 61, 62 to escape and to be attached so as not to be pinched.

[0143] Since the first case 11-1 and the second case 11-2 are metal cases formed by processing a metal plate, the part precision is improved compared to the case where they are formed by resin molding. Moreover, the first case 11-1 and the second case 11-2 are common members having the same shape. As a result, case 10 is configured such that each case lid portion 112-1, 112-2 faces a pair of elastic support portions 81, 82, and the case openings 111-1, 111-2 are aligned and connected to close each other, thereby defining the dimension between case lid portions 112-1, 112-2. Based on this, when manufacturing vibration actuator 1, the dimension of the range of motion of movable body 20, that is, the length in the vibration direction which is the range of movement of movable body 20 inside case 10, is formed to be a stable length.

[0144] This makes it possible to realize a vibration actuator 1 that ensures stable vibration, thereby stabilizing the vibration characteristics and enabling a larger input voltage.

[0145] <First spacer 13-1, second spacer 13-2> The first spacer 13-1 and the second spacer 13-2 are attached to the upper and lower ends of the drive unit 15 so as to sandwich the drive unit 15, and stably accommodate the drive unit 15 within the case 10 while allowing the movable body 20 of the drive unit 15 to vibrate.

[0146] The first spacer 13-1 and the second spacer 13-2 ensure a separation length between the case lids 112-1, 112-2 and the elastic support members 81, 82. This ensured separation length is the displacement length of the movable space of the movable body 20, and is a space within a range in which the elastic support members 81, 82 are not plastically deformed. Even if a force exceeding a predetermined vibration range is applied to the movable body 20 due to, for example, a drop impact, the elastic support members 81, 82 contact the fixed body 40 (at least one of the case lids 112-1, 112-2) without plastic deformation, so that the elastic support members 81, 82 are not damaged and reliability can be improved.

[0147] The first spacer 13-1 and the second spacer 13-2 are disposed and fixed within the first case 11-1 and the second case 11-2.

[0148] In detail, the first spacer 13-1 and the second spacer 13-2, together with both ends (end flanges 427, 428) of the coil holding portion 42, sandwich and fix the outer circumferential portions 806 of the elastic support portions 81, 82 in the vibration direction. The first spacer 13-1 and the second spacer 13-2 may be made of a magnetic or non-magnetic material, for example, made of a metal such as SUS.

[0149] The first spacer 13-1 and the second spacer 13-2 have the same shape and are made of the same material, and are therefore a common material, which eliminates the need to manufacture the first spacer 13-1 and the second spacer 13-2 separately and allows them to be manufactured as a common part.

[0150] The first spacer 13-1 and the second spacer 13-2 are arranged within the case 10 and have a main body portion 132 having a thickness that separates the elastic support portions 81, 82 from the case lid portions 112-1, 112-2 so that they can be displaced, and an engagement recess 134 with which the engagement protrusions 44, 45 engage.

[0151] The main body 132 is, for example, annular, and has an outer diameter similar to the outer diameters of the upper and lower ends of the drive unit 15 (coil holding portion 42).

[0152] The engaging recess 134 engages with the engaging protrusions 44, 45 in the axial direction in the main body 132 to restrict their mutual circumferential movement. The engagement recesses 134 are formed in the main body 132 at positions corresponding to the engagement protrusions 44 , 45 .

[0153] The drive unit 15 disposed inside the case 10 can be accommodated so as to be freely positioned in the circumferential direction.

[0154] <Operation of vibration actuator 1> The operation of the magnetic circuit configuration of the vibration actuator 1 will be described with reference to Fig. 9. Fig. 9 is a diagram showing a schematic diagram of the magnetic circuit configuration of the vibration actuator.

[0155] The operation of the vibration actuator 1 will be described using as an example a case in which the magnet 21 is magnetized so that the front surface 21a on one side of the magnetization direction (the upper side in this embodiment) is an N pole and the back surface 21b on the other side of the magnetization direction (the lower side in this embodiment) is an S pole.

[0156] In vibration actuator 1, movable body 20 is considered to correspond to the mass part in a vibration model of a spring-mass system, so when resonance is sharp (has a steep peak), the steep peak is suppressed by damping the vibration. By damping the vibration, the resonance becomes less steep, and the maximum amplitude value and maximum movement amount of movable body 20 at resonance do not vary, and vibration with an appropriate and stable maximum movement amount is output.

[0157] When the vibration actuator 1 is in a non-driven state, a magnetic flux flow mf is formed, which is emitted from the surface 21a side of the magnet 21, radiated from the first weight portion 23 to the coil 61 side, passes through the outer yoke 50, and enters the magnet 21 from the second weight portion 25 below the magnet 21 via the coil 62. As shown in Fig. 9, when a current is applied, a Lorentz force in the -f direction is generated in the pair of coils 61 and 62 according to Fleming's left-hand rule due to the interaction between the magnetic field of the magnet 21 and the current flowing through the coils (a pair of coils 61 and 62). A force opposite to this Lorentz force in the -f direction is generated in the movable body 20 having the magnet 21 as a thrust in the F direction, and the movable body 20 having the magnet 21 moves in the F direction, that is, toward the case lid portion 112-1 side of the first case 11-1. Also, when the current direction of the pair of coils 61, 62 is switched to the opposite direction and current is passed through the pair of coils 61, 62, a Lorentz force in the opposite direction f is generated, and according to the law of action and reaction, a force opposite to the Lorentz force in the f direction is generated as a thrust (thrust in the -F direction) on the movable body 20. As a result, the movable body 20 moves in the -F direction, that is, toward the case cover 112-2 side of the second case 11-2. Note that, when no current is passed and no vibration is occurring, a magnetic attraction force acts between the magnet 21 and the outer yoke 50, and they function as magnetic springs. The magnetic attraction force generated between the magnet 21 and the outer yoke 50 and the restoring force of the elastic support parts 81, 82 that return to their original shapes return the movable body 20 to its original position.

[0158] According to this embodiment, in the vibration actuator 1, the exterior is made of a metal case made of a common material divided into two parts, first case 11-1 and second case 11-2, above and below, thereby ensuring strength and making it more durable than a resin case, thereby improving the strength reliability of the vibration actuator.

[0159] In addition, in the movable body 20, the first weight portion 23 and the second weight portion 25 are made of ferromagnetic material such as tungsten, and a single component has the functions of both a weight and a yoke. By increasing the weight of the movable portion, the vibration characteristics can be improved.

[0160] Furthermore, the vibration actuator 1 is constructed using the same materials for the upper and lower parts, except for the configuration of the coil holding portion 42 and the magnet 21. Therefore, when manufacturing the vibration actuator 1, there is no need to manufacture the upper and lower parts separately, which allows for reduced costs.

[0161] <Modification> FIG. 10 is a perspective view showing a modified example of the spacer in the vibration actuator of the present embodiment.

[0162] 10 has an annular main body 132A similar to the spacer 13, and an engagement recess 134A formed in the same shape and with the same function as the engagement recess 134, and also has a cone-shaped spacer lid 1360 on the inner diameter side of the annular main body 132A. The spacer 13A is made of, for example, resin. Note that the spacer lid 1360 also functions as a bottom depending on its position in the vibration actuator 1A.

[0163] Fig. 11 is a vertical cross-sectional view of a vibration actuator with a modified spacer, and Fig. 12 is an enlarged view of part X in Fig. 11. Note that the vibration actuator 1A shown in Fig. 11 has the same configuration as the vibration actuator 1, except that the first spacer 13-1 and the second spacer 13-2 are replaced with spacers 13A (first spacer 13A-1 and second spacer 13A-2), respectively. Therefore, similar members are given the same names and symbols and their explanations are omitted.

[0164] The spacer lid 1360 is formed in a tapered shape with an inclined inner surface so that the thickness becomes thinner toward the center. An opening 138A is provided in the center of the spacer lid 1360. The outer surface of the spacer lid 1360 is flat as shown in Figures 11 and 12, and abuts against the case lids 112-1 and 112-2 of the first case 11-1 and the second case 11-2. Figure 12 shows the normal movable area of ​​the movable body 20 (area shown by hatching surrounded by a dotted line) and the dead space DS (area surrounded by a dotted line).

[0165] By making the spacer lid portion 1360 tapered, when the spacer 13A is arranged together with the drive unit 15 in the first case 11-1 and the second case 11-2, the spacer lid portion 1360 can be provided in the dead space DS in the case 10. As a result, even if the vibration actuator 1 is subjected to an external force such as a drop impact, the elastic support portions 81, 82 come into contact with the spacer lid portion 1360 of the spacer 13A, thereby restricting the movement of the elastic support portions 81, 82 and further preventing plastic deformation of the elastic support portions 81, 82. Note that, at this time, the support fixing portions 314, 334 of the spring connecting portions 31, 33 are inserted into the opening portion 138A and are not in contact with the spacer lid portion 1360.

[0166] In this way, the spacer is configured to be placed in the dead space DS, and may be configured in any manner as long as it has the same basic configuration as the spacers 13 and 13A.

[0167] The vibration actuator 1 is driven by an AC wave input from a power supply unit (for example, the drive control unit 203 shown in Figs. 13 and 14) to a pair of coils 61, 62. In other words, the direction of current flow through the pair of coils 61, 62 switches periodically, and a thrust in the F direction on the case lid 112-1 side of the first case 11-1 and a thrust in the -F direction on the case lid 112-2 side of the second case 11-2 act alternately on the movable body 20, as shown in Fig. 9. This causes the movable body 20 to vibrate in the vibration direction.

[0168] The following is a brief explanation of the driving principle of the vibration actuator 1. In the vibration actuator 1 of this embodiment, the mass of the movable body 20 is m [kg], the spring constant of the springs (elastic support members 81 and 82 which are springs) is K sp In this case, the movable body 20 has a resonance frequency F r Vibrates at [Hz].

[0169]

number

[0170] Since the movable body 20 is considered to constitute a mass part in a vibration model of a spring-mass system, the coil (a pair of coils 61, 62) is set to have a resonance frequency F r When an AC wave having a frequency equal to the resonant frequency F of the movable body 20 is input, the movable body 20 enters a resonant state. r By inputting an AC wave having a frequency substantially equal to that of the movable body 20, the movable body 20 can be vibrated efficiently.

[0171] Below are equations of motion and circuit equations that show the driving principle of the vibration actuator 1. The vibration actuator 1 is driven based on the equation of motion shown in the following equation (2) and the circuit equation shown in the following equation (3).

[0172]

number

[0173]

number

[0174] That is, the mass m [kg], the displacement x(t) [m], and the thrust constant K f [N / A], current i(t) [A], spring constant K sp [N / m], damping coefficient D [N / (m / s)], etc. can be changed as appropriate within the range that satisfies formula (2). In addition, voltage e(t) [V], resistance R [Ω], inductance L [H], back electromotive force constant K e [V / (rad / s)] can be changed as appropriate within the range that satisfies formula (3).

[0175] In this way, in the vibration actuator 1, the mass m of the movable body 20 and the spring constant K sp The resonant frequency F is determined by r When the coils 61 and 62 are energized with an AC wave corresponding to the above, a large vibration output can be efficiently obtained.

[0176] Furthermore, the vibration actuator 1 satisfies equations (2) and (3) and is driven by a resonance phenomenon using the resonance frequency shown in equation (1). As a result, the vibration actuator 1 can be driven with low power consumption, that is, the movable body 20 can be vibrated in a linear reciprocating manner with low power consumption. Furthermore, by increasing the damping coefficient D, vibrations can be generated over a wide frequency range.

[0177] According to this embodiment, the vibration actuator 1 can stably drive the movable body 20 in the vertical direction, and at the same time, can efficiently distribute the magnetic flux of the pair of coils 61, 62 from the upper and lower elastic support parts 81, 82 of the magnet 21. This enables the vibration actuator 1 to achieve high-output vibration.

[0178] (electronic equipment) Figures 13 and 14 are diagrams showing an example of a mounting form of the vibration actuator 1. Figure 13 shows an example in which the vibration actuator 1 is mounted on a game controller GC, and Figure 14 shows an example in which the vibration actuator 1 is mounted on a mobile terminal M.

[0179] The game controller GC is connected to the game console via wireless communication, for example, and is used by the user by grasping or holding it. The game controller GC here has a rectangular plate shape, and is operated by the user grasping the left and right sides of the game controller GC with both hands.

[0180] The game controller GC notifies the user of commands from the game machine main unit by vibration. Although not shown, the game controller GC also has functions other than command notification, such as an input operation unit for the game machine main unit.

[0181] The mobile terminal M is, for example, a mobile communication terminal such as a mobile phone, a smartphone, etc. The mobile terminal M notifies the user of an incoming call from an external communication device by vibration, and realizes each function of the mobile terminal M (for example, a function that provides a sense of operation and a sense of realism).

[0182] The game controller GC and the mobile terminal M each have a communication unit 201, a processing unit 202, a drive control unit 203, and vibration actuators 204, 205, and 206 which are vibration actuators 1 serving as drive units. Note that a plurality of vibration actuators 204, 205 are implemented in the game controller GC.

[0183] In the game controller GC and the portable terminal M, the vibration actuators 204-206 are preferably mounted so that, for example, the main surface of the terminal and a surface perpendicular to the vibration direction of the vibration actuators 204-206, in this case the case lids (bottoms) 112-1 and 112-2 of the first cases 11-1 and 11-2, are parallel to each other.

[0184] The main surface of the terminal is the surface that comes into contact with the user's body surface, and in this embodiment, it means the vibration transmission surface that comes into contact with the user's body surface and transmits vibrations. Note that the main surface of the terminal and the case lids (bottoms) 112-1 and 112-2 of the vibration actuators 204, 205, and 206 may be arranged so as to be perpendicular to each other.

[0185] Specifically, in the game controller GC, vibration actuators 204 and 205 are mounted so that the vibration direction is perpendicular to the surface that the operating user's fingertips, finger pads, or hand contacts, or the surface on which the operation unit is provided. In addition, in the case of the portable terminal M, vibration actuator 206 is mounted so that the vibration direction is perpendicular to the display screen (touch panel surface). As a result, vibrations in a direction perpendicular to the main surfaces of the game controller GC and the portable terminal M are transmitted to the user.

[0186] The communication unit 201 is connected to an external communication device via wireless communication, receives a signal from the communication device, and outputs it to the processing unit 202. In the case of a game controller GC, the external communication device is a game console main unit as an information communication terminal, and communication is performed according to a short-range wireless communication standard such as Bluetooth (registered trademark). In the case of a mobile terminal M, the external communication device is, for example, a base station, and communication is performed according to a mobile communication standard.

[0187] The processing unit 202 converts the input signal into a drive signal for driving the vibration actuators 204, 205, 206 using a conversion circuit unit (not shown), and outputs the drive signal to the drive control unit 203. In the mobile terminal M, the processing unit 202 generates a drive signal based on the signal input from the communication unit 201 as well as signals input from various functional units (not shown, for example, an operation unit such as a touch panel).

[0188] The drive control unit 203 is connected to the vibration actuators 204, 205, and 206, and is equipped with circuits for driving the vibration actuators 204, 205, and 206. The drive control unit 203 supplies drive signals to the vibration actuators 204, 205, and 206.

[0189] The vibration actuators 204, 205, and 206 are driven in accordance with a drive signal from the drive control unit 203. Specifically, in the vibration actuators 204, 205, and 206, the movable body 20 vibrates in a direction perpendicular to the main surfaces of the game controller GC and the mobile terminal M.

[0190] The vibrations perpendicular to the body surface are transmitted to the body surface of the user in contact with the game controller GC or the mobile terminal M, so that the user can be given a sufficient bodily sensation. In the game controller GC, the bodily sensation of the vibration can be given to the user by one or both of the vibration actuators 204, 205, and highly expressive vibrations can be given, such as at least selectively giving strong and weak vibrations.

[0191] The invention made by the inventor has been specifically described above based on an embodiment, but the present invention is not limited to the above embodiment and can be modified within the scope of the gist of the invention.

[0192] Furthermore, the vibration actuator according to the present invention may be mounted on a contact part with a user of a portable device other than the game controller GC and the portable terminal M (for example, a portable information terminal such as a tablet PC, a portable game terminal, etc.). That is, the vibration actuator 1 may be mounted on a contact part with a user in a handheld electric device such as a portable terminal or an electric beauty appliance such as a facial massager. The vibration actuator 1 may be mounted on a contact part with a user in a wearable terminal worn by a user. In the case of a handheld electric device such as a game controller GC, the contact part with the user is, for example, a handle part that the user holds when using the device, and in the case of a wearable electric device such as a facial massager, the contact part with the user is, for example, a pressure part that applies pressure to the surface of the user's body. [Industrial Applicability]

[0193] The vibration actuator according to the present invention can generate a suitable vibration output while being miniaturized, and is useful for being mounted in electronic devices such as game console terminals or mobile terminals, and electrical devices such as electric beauty salon appliances. [Explanation of symbols]

[0194] 1, 1A, 204, 205, 206 Vibration Actuator 10 Cases 11-1 Case 1 11-2 Case 2 13 Spacer (spacer part) 13-1, 13A-1 First spacer 13-2, 13A-2 Second spacer 15 Drive unit 20 Movable body 20a Outer surface 21 Magnet 21a surface 21b Back side 23 First weight section 25 Second weight section 31, 33 Spring connection 40 Fixed body 41 Wiring section 42 Coil holding portion (cylindrical body) 42a Inner surface 42b, 42c Coil mounting part 43 Terminal entanglement part 44, 45 Engagement protrusion 46 Terminal drawer 47 Connecting groove 50 Outer Yoke 51 Yoke body 52 End 53, 55 Opening 55a Upper part 55b Bottom 61, 62 Coil 63, 64 Windings 81, 82 Elastic support part 111-1, 111-2 Case opening 112-1, 112-2 Case lid 114-1, 114-2 Peripheral wall part 116-1, 116-2 Notch 118-1, 118-2 Positioning holes 134 Engagement recess 201 Communications Department 202 Processing section 203 Drive control unit 232, 252 Weight opening (opening) 312 Connection body 313, 333 Spring fixing part 314 Support fixing part 332 Connection body 334 Support fixing part 412 Coil guide 420 Concave part 422 Cylindrical main body 426, 427, 428 Flange part 426a Outer periphery 427a, 428a Open end surface 432 Ferret 533 Cutout 802 Inner circumference 802a Connection hole 804 Transformable Arm 806 Outer periphery 808 Positioning groove

Claims

1. a movable body including a disk-shaped magnet, a pair of weight portions that are magnetic bodies fixed to both sides of the magnet in an axial direction, and a pair of spring connection portions provided at both ends in the axial direction; a fixed body including a cylindrical body having an annular coil disposed on an outer periphery thereof and housing the movable body so as to be capable of reciprocating vibration in the axial direction by a pair of elastic support parts spaced apart in the axial direction and connected to the pair of spring connection parts; and a fixed body including a case. Equipped with the case includes a pair of bottomed cylindrical cases, each of which has a case lid at one end and a case opening at the other end, and the pair of bottomed cylindrical cases are each placed over the cylindrical body from both sides in the axial direction, and the case openings of the pair of bottomed cylindrical cases are joined together to accommodate the cylindrical body; The pair of bottomed cylindrical cases are common members having the same shape. Vibration actuator.

2. Each of the pair of bottomed cylindrical cases has a notch on an edge of the case opening, and a terminal connection portion of the cylindrical body is inserted into a notch opening formed by joining the notches together.

2. The vibration actuator according to claim 1.

3. The elastic support part is disk-shaped, its center part is connected to the spring connection part, and its outer periphery is sandwiched between the open end part of the cylindrical body and a spacer part, and is fixed at a distance from the case lid part via the spacer part.

2. The vibration actuator according to claim 1.

4. A protrusion is provided at each of the open ends of the cylindrical body, protruding in the axial direction from each open end, and engaging with the spacer portion through the elastic support portion.

4. The vibration actuator according to claim 3.

5. The spacer portion has a recess with which the protrusion engages to restrict mutual circumferential movement.

5. The vibration actuator according to claim 4.

6. A handheld or wearable electrical device, A vibration actuator according to any one of claims 1 to 5 is mounted on a part that comes into contact with a user. Electrical equipment.

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