Vibration actuator and contact-type input device

Abstract

This vibration actuator comprises: a core; a coil disposed around the core; and a substrate disposed on the core and integrally provided with a wiring part connected to the coil and an insulating part that is disposed inside the coil and insulates the coil and the core.

Description

Vibration actuator and contact-type input device

[0001] The present invention relates to a vibration actuator and a contact-type input device equipped with the same.

[0002] Conventionally, a configuration has been known in which a vibration actuator is used to impart vibrations to the pads of an operator's fingers that come into contact with a display screen displayed on a touch panel, which is a sensing panel, in order to provide a touch operation sensation (the sensation of operating by touch) (Patent Document 1).

[0003] Patent Document 1 discloses a mobile terminal device in which a vibration actuator is attached to the back surface of a touch panel via a vibration transmission unit. The vibration actuator of this device has a mover disposed within a housing fixed to the vibration transmission unit so that the mover can move back and forth along a guide shaft disposed perpendicular to the touch panel. The vibration actuator applies vibration to the finger pad that touches the touch panel via the vibration transmission unit, although there is a possibility that a collision sound will be generated when the mover hits the housing in response to an operation on the touch panel.

[0004] JP 2015-070729 A

[0005] Incidentally, in the vibration actuator of Patent Document 1, the movable element moves back and forth along a guide shaft arranged perpendicular to the display surface of the touch panel, so the device itself has a length, or thickness, perpendicular to the display surface.

[0006] Therefore, there is a demand for a vibration actuator that can be made thinner and lower in height as a device itself.

[0007] Furthermore, the drive circuit of the vibration actuator in Patent Document 1 has a magnet and two yokes sandwiching the magnet as the mover, and a bobbin surrounding the mover and two coils wound around the bobbin as the stator, which takes time to assemble, and therefore there is a demand for further reducing the number of parts and improving assembly ease.

[0008] An object of the present invention is to provide a vibration actuator and a contact-type input device that are easy to assemble and can be made low-profile.

[0009] The vibration actuator of the present invention has a configuration including a core, a coil arranged around the core, a wiring portion arranged on the core and connected to the coil, and a substrate arranged inside the coil and integrally comprising an insulating portion that insulates the coil from the core.

[0010] In addition, in the above configuration, the vibration actuator may also be configured to include an electromagnet having the substrate and the coil arranged in the center of the core, plates having magnetic bodies arranged opposite both ends of the core, and elastic support parts supporting the core on both sides of the coil and connected to the plate, in which the magnetic force generated by passing current through the coil via the substrate causes one of the coil or the plate to displace and vibrate so as to approach the other.

[0011] The contact-type input device of the present invention is a contact-type input device in which a vibration actuator of the above-described configuration is arranged on the back side of the operating surface, and current is passed through the coil in response to a user's contact action on the operating surface, causing one of the coil or the plate to displace and vibrate so as to approach the other, thereby presenting a tactile sensation to the user.

[0012] According to the present invention, assembly is easy and a low profile can be achieved.

[0013] FIG. 1 is an external perspective view of a vibration actuator according to a first embodiment of the present invention. FIG. 2 is a plan view of the vibration actuator. FIG. 3 is a bottom view of the vibration actuator. FIGS. 4A and 4B are front and rear views of the vibration actuator. FIGS. 5A and 5B are right and left side views of the vibration actuator. FIG. 6 is a cross-sectional view taken along line A-A in FIG. 2. FIG. 7 is a cross-sectional view taken along line B-B in FIG. 2. FIG. 8 is an exploded perspective view of a vibration actuator according to a first embodiment of the present invention. FIG. 9 is a perspective view showing a state in which the coil has been removed from the core body of the vibration actuator according to the first embodiment of the present invention. FIG. 10 is an exploded perspective view of the core body. FIG. 11 is a plan view of the substrate. FIG. 12 is a left side view of the core body of the vibration actuator according to the first embodiment of the present invention. FIG. 13 is a partial cross-sectional view showing the positional relationship between the substrate and the coil in the core body of the vibration actuator according to the first embodiment of the present invention. FIG. 14 is a diagram illustrating the magnetic circuit of the vibration actuator. FIG. 15 is a diagram illustrating a method of assembling the movable part. FIG. 16 is a diagram showing the circuit configuration of a control unit of a vibration actuator according to embodiment 1. FIG. 17 is a diagram showing an example of a vibration presentation device having a vibration actuator. FIG. 18 is a perspective view of the appearance of a vibration actuator according to embodiment 2 of the present invention. FIG. 19 is a plan view of the same vibration actuator. FIG. 20 is a bottom view of the same vibration actuator. FIGS. 21A and 21B are front and rear views of the same vibration actuator. FIGS. 22A and 22B are right and left side views of the same vibration actuator. FIG. 23 is an exploded perspective view of a vibration actuator according to embodiment 2 of the present invention. FIG. 24 is a perspective view showing a state in which the coil has been removed from the core body of the vibration actuator according to embodiment 2 of the present invention. FIG. 25 is an exploded perspective view of the core body. FIG. 26 is a plan view of a vibration actuator of modified example 1. FIG. 27 is a bottom view of the vibration actuator of modified example 1. FIGS. 28A and 28B are front and rear views of the vibration actuator of modified example 1. FIGS. 29A and 29B are right and left side views of the vibration actuator of modified example 1. 30 is a plan view of the vibration actuator of Modification 2. FIG. 31 is a bottom view of the vibration actuator of Modification 2.Figures 32A and 32B are a front view and a rear view of the vibration actuator of Modification 2. Figures 33A and 33B are a right side view and a left side view of the vibration actuator of Modification 2.

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

[0015] In this embodiment, the description will be given using a Cartesian coordinate system (X, Y, Z). The same Cartesian coordinate system (X, Y, Z) will also be used in the figures described below. In the following, the vibration actuator 10 is used, for example, in a contact-type input device, and the width, depth, and height of this contact-type input device correspond to the lengths in the X, Y, and Z directions, respectively. The width, depth, and height of the vibration actuator 10 also correspond to the lengths in the X, Y, and Z directions, respectively. Note that in the description of each component constituting the vibration actuator 10, the surface on the "flat side" (or "upper side") will be referred to as the "front surface" (or "top surface"), and the surface on the "rear side" (or "lower side") will be referred to as the "back surface" (or "lower surface").

[0016] (Embodiment 1) <Overall configuration of vibration actuator 10> Fig. 1 is an external perspective view of a vibration actuator according to embodiment 1 of the present invention, Fig. 2 is a plan view of the same vibration actuator, and Fig. 3 is a bottom view of the same vibration actuator. Also, Figs. 4A and 4B are front and rear views of the same vibration actuator, and Figs. 5A and 5B are right and left side views of the same vibration actuator. Furthermore, Fig. 6 is a cross-sectional view taken along line A-A in Fig. 2, Fig. 7 is a cross-sectional view taken along line B-B in Fig. 2, and Fig. 8 is an exploded perspective view of the vibration actuator according to embodiment 1 of the present invention.

[0017] The vibration actuator 10 is preferably used in a vibration presentation device (for example, a track pad) that is a contact-type input device serving as an operating device that serves as a vibration presentation section (operation surface) that an operator touches to perform an operation.

[0018] By vibrating the operating device, the vibration actuator 10 can give the operator who touches and operates the operating device a sense of touch (also called a "tactile sensation" or "force sensation") depending on the purpose and usage situation of the operating device.

[0019] The vibration actuator 10 is a thin vibration actuator in the form of a flat plate or a thin plate. If the Z direction is the thickness direction of the plate (plate thickness), the vibration actuator 10 is disposed opposite the back side of the operating device in the thickness direction and vibrates the operating device.

[0020] The vibration actuator 10 shown in Figures 1 to 8 is formed in the shape of a thin plate, and has a movable part 20, a base part (hereinafter also referred to as a "base plate") 30, and a plate-shaped elastic part 40 as an elastic support part (elastic body) that supports the movable part 20 so that it can move freely relative to the base part 30.

[0021] Although the elastic support portion is the plate-shaped elastic portion 40, it is not limited to a plate-shaped portion as long as it supports the movable portion 20 so as to be freely movable relative to the base portion 30.

[0022] The vibration actuator 10 vibrates as the movable part 20 moves towards and away from the base part 30 in the Z direction, which is the thickness direction of the plate, specifically towards the base part 30, and this vibration gives the user operating the operating device to which the vibration actuator 10 itself is attached a sense of operation.

[0023] In the vibration actuator 10, the movable part 20, the base part 30, and the plate-like elastic part (elastic support part) 40 are all configured to have a flat shape, and are configured to minimize the space occupied in the thickness direction, which is the vibration direction, within the range of movement of the movable part 20. In the vibration actuator 10, one of the movable part 20 and the base part 30 can be connected to a vibration presentation part that receives a pressing operation by the user.

[0024] <Movable section 20> As shown in Fig. 8, the movable section 20 has a core body 60 equipped with the coil 50, and a plate-shaped weight section 70 as a weight section. Although the movable section 20 has the core body 60, it may be configured without the plate-shaped weight section 70. Fig. 9 is a perspective view showing a state in which the coil has been removed from the core body of the vibration actuator according to embodiment 1 of the present invention, and Fig. 10 is an exploded perspective view of the core body.

[0025] 8 to 10 , the core body 60 has the coil 50, a core 62 around which the coil 50 is wrapped, a substrate 80 connected to the coil 50, and a protective film 68 that covers the outside of the coil 50. The core body 60 constitutes an electromagnet having the coil 50 and the core 62, and power is supplied to the coil 50 via the substrate 80. Note that the protective film 68 is omitted from the figures as appropriate.

[0026] The coil 50 is formed in a flat rectangular plate shape and is arranged to surround the center of the flat rectangular plate-shaped core 62. The coil 50 is arranged on the outer periphery of the center of the core 62 via an insulating part 822 of the substrate 80, and is arranged so as not to come into direct contact with the core 62.

[0027] The core (magnetic core) 62 is a rectangular plate-shaped magnetic body, and is surrounded by the coil 50 . Both ends 621 and 622 of the core 62 protrude from the coil 50 in the direction of the winding axis of the coil 50 .

[0028] The core 62 is magnetized by energizing the coil 50 and functions as an electromagnet. The ends 621 and 622 become magnetic poles, generating a magnetic attraction force between the core 62 and the nearby magnetic body, i.e., the base portion 30.

[0029] Specifically, when current is applied to the coil 50, both ends 621, 622 of the core 62, particularly the back surfaces of both ends 621, 622, become planar magnetic pole faces. The core 62 is preferably made of a soft magnetic material such as silicon steel plate, permalloy, or ferrite. The core 62 may also be made of electromagnetic stainless steel, a sintered material, a metal injection molding (MIM) material, a laminated steel plate, an electro-galvanized steel plate (SECC), or the like.

[0030] The core 62 is long in the winding axis direction of the coil 50, and spring connection portions 631, 632, which are hole portions for joining to the plate-shaped elastic portion 40, are provided at both ends 6210, 6220 of the two end portions 621, 622 of the core 62 that are spaced apart in the longitudinal direction, which is the winding axis direction.

[0031] The core 62 has the coil 50 disposed in the center of the rectangular plate-shaped core body. The core body is wider than both ends 6210, 6220, and has a substrate 80 disposed on the surface side that partially covers the periphery of the core body.

[0032] 11 is a plan view of the substrate 80. The substrate 80 is disposed on the core 62 and integrally includes a wiring portion 84 having wiring connected to the coil 50, and an insulating portion 822 that insulates the coil 50 from the core 62.

[0033] The wiring portion 84 of the substrate 80 is provided on the flexible insulating sheet 82 of the substrate 80, and is continuous with the insulating portion 822. The wiring portion 84 is wired on a portion 821 of the insulating sheet 82, and has a land portion 85 for coil wiring and a land portion 86 for external connection.

[0034] The substrate 80 may be, for example, a flexible substrate and may be made up of multiple layers. For example, the insulating sheet 82 is made of a flexible insulating material such as polyimide, and wiring including coil wiring lands 85, external connection lands 86, etc. is provided on a portion of the surface of the insulating sheet 82 to form the wiring section 84.

[0035] The wiring portion 84 is disposed on the surface of the core 62 across the entire width of the core 62. The insulating portion 822 is wider than the portion 821 where the wiring portion 84 is wired, and has a width in a direction perpendicular to the axial direction of the core 62 and a length that covers the outer periphery of the core 62.

[0036] The insulating portion 822 is flexible and is arranged on the surface of the central portion of the core 62, and is arranged so as to wrap around the core 62 from both left and right ends and cover both side surfaces and the back surface.

[0037] The insulating portion 822 is, for example, in the form of a sheet that is continuous with a portion 821 of a single insulating sheet 82, and has a surface covering portion 823 that is arranged on the surface of the core 62, and back covering portions 824, 825 that are continuous with both side portions of the surface covering portion 823.

[0038] The back surface covering portions 824, 825 are provided extending via bendable portions 826 on both side portions of the front surface covering portion 823 that are spaced apart in a direction perpendicular to the direction adjacent to the wiring portion 84. The back surface covering portions 824, 825 cover the back surface of the core 62 from both side portions of the core 62 whose front surface is covered by the front surface covering portion 823. Note that the insulating portion 822 may not be entirely flexible, and may be configured to be bendable only at the corners of the core 62, for example, as long as it can be wound around the core 62.

[0039] The bendable portion 826 covers the corners (see edge portions 629 in FIG. 10) of the core 62. The insulating portion 822 is arranged so as to be wound around the outer periphery of the core 62, and the coil 50 is arranged on the outer surface side thereof.

[0040] The insulating portion 822 functions as a protective film on the inside of the coil, and prevents short circuits between the coil 50 and the core 62. The insulating portion 822 is provided with holes 831 for positioning when attaching the substrate 80 to the core 62. The substrate 80 is fixed to the core 62 using adhesive or double-sided tape. The insulating portion 822 is also fixed to the exterior coil 50 using an adhesive or the like.

[0041] FIG. 12 is a left side view of the core body in the vibration actuator according to embodiment 1 of the present invention, and FIG. 13 is a partial cross-sectional view showing the positional relationship between the substrate and coil in the core body of the vibration actuator according to embodiment 1 of the present invention.

[0042] 12 and 13 , in the core body 60, the wiring portion 84 of the substrate 80 has a thickness t on the core 62, and the insulating portion 822 is disposed adjacent to the wiring portion 84. That is, the wiring portion 84 has a thickness greater than that of the insulating portion 822 on the core 62, and is disposed adjacent to the insulating portion 822 on the core 62.

[0043] When the coil 50, which has been wound in a cylindrical shape beforehand, is sheathed around the insulating portion 822, or when a cylindrical coil 50 is provided by winding a coil wire around the insulating portion 822, the coil 50 is positioned on the insulating portion 822. At this time, the coil 50 is provided adjacent to the wiring portion 84, and the coil 50 abuts against a part of the wiring portion 84, which functions to position the coil 50. As a result, in the substrate 80, the wiring portion 84 can suitably sheathe the coil 50 around the core 62 via the insulating portion 822.

[0044] Furthermore, the corners of the rectangular plate-shaped core 62 (see edge portions 629 in Figure 10) are covered with the insulating portion 822, so when the coil 50 is wrapped around the core 62 via the insulating portion 822, it can be wrapped around the core 62 in an appropriate manner without being damaged by the edge portions 629 of the core 62.

[0045] The core body 60 has a substrate (e.g., FPC) 80 in the center of the core 62, which combines the function of insulating the core 62 inside the coil 50 and the function of wiring to the coil 50. This makes it possible to easily assemble a vibration actuator that is thin and low-profile without requiring separate components with individual functions when assembling the core body 60, and ultimately the vibration actuator 10.

[0046] <Plate-shaped weight portion 70> The plate-shaped weight portion 70 shown in Figures 1 to 8 functions as a weight that promotes vibration, and is provided in accordance with the shape of the core 62, for example, the width (length in the X direction) and the length in the depth direction (length in the Y direction).

[0047] The plate-shaped weight portion 70 is fixed to the core 62 located on both end sides of the coil 50. For example, the core 62 is fixed to the plate-shaped elastic portion 40 via fastening members 55 at spring connection portions 631, 632 thereof.

[0048] The plate-shaped weight portion 70 is a frame-shaped member having an opening (opening 72 ) in the region of the coil 50 , and has an opening 74 continuous with the opening 72 in the region of the wiring portion 84 .

[0049] The plate-shaped weight portion 70 is fixed to the core body 60 with the thickness of the coil 50 and the wiring portion 84 relieved at the openings 72, 74, so that the vibration actuator 10 can be made low-profile and vibration can be adjusted.

[0050] Furthermore, the weight of the plate-shaped weight portion 70 can be set arbitrarily, for example, by adjusting the length of the plate-shaped weight portion 70 in the Y direction, the length in the Z direction, or the material. In this way, the plate-shaped weight portion 70 can adjust the weight of the movable portion 20, and this adjustment can set the natural frequency. Note that, if the arrangement space for the thickness (Z direction) is limited, the plate-shaped weight portion 70 may be shaped so that its weight increases in the X and Y directions. When a vibration presentation unit (e.g., a trackpad body, etc.) that receives a user's pressing operation is attached to the movable portion 20, it is preferable that the vibration presentation unit be attached to the plate-shaped weight portion 70 via a fixing material such as an adhesive, a fastening member, or a pressure-sensitive adhesive.

[0051] 1 to 8 , the base portion 30 movably supports the movable portion 20 via the plate-shaped elastic portion 40 in the approaching and separating direction of the base portion 30, that is, the Z direction in FIG. 1 . The base portion 30 has opposing portions 321, 322 made of magnetic material that are arranged opposite both end portions 621, 622 of the core 62 with a gap (gap) G therebetween in an opposing direction that intersects with the winding axis direction of the coil 50. The base portion 30 is a flat-shaped member having a predetermined thickness in the Z direction, and is, for example, plate-shaped, and forms the bottom surface of the vibration actuator 10. The base portion 30 may also be referred to as a base plate.

[0052] The base portion 30 has a base main body portion 31 which is a magnetic material, and the base main body portion 31 is provided with magnetic opposing portions (magnetic materials) 321, 322 which are arranged opposite both end portions 621, 622 of the core 62, spring connection portions 341, 342, and a fixing portion 36.

[0053] The base main body 31 has an opening 38 in the center, and is formed into a square frame shape in plan view by a pair of adjacent sides 311, 312. The opening 38 is a space into which the lower part of the coil 50 is inserted, and is formed into a shape corresponding to the outer shape of the coil 50, for example, a square shape.

[0054] In the base main body portion 31, opposing portions 321, 322 made of magnetic material are provided on each of a pair of side portions (X side portions) 311 that are opposed to and spaced apart from each other, and spring connection portions 341, 342 are provided on each of another pair of side portions (Y side portions) 312 adjacent to the pair of side portions 311.

[0055] A pair of side portions 311 and another pair of side portions 312 are each planar bodies, and a notch is formed in the center of each of the four outer edge portions that form the outer periphery of the base main body portion 31 to ensure a deformation area for a portion of the plate-shaped elastic portion 40.

[0056] The opposing portions (opposing surfaces) 321, 322 are part of the base portion 30 and are magnetic bodies arranged opposite both end portions 621, 622 of the core 62 with a gap G in an opposing direction that intersects the winding axis direction of the coil 50, for example, in the Z direction.

[0057] When current is passed through the coil 50, the opposing portions 321, 322 are attracted to the opposite ends 621, 622 by a magnetic attraction force generated between the opposing portions 321, 322 and the rear surfaces of the opposite ends 621, 622 of the core 62. In other words, the opposing portions 321, 322 attract the opposite ends 621, 622.

[0058] The facing portions 321 and 322 are formed, for example, at the center of each of the pair of side portions 311 and are disposed at positions sandwiching the opening 38 in the Y direction.

[0059] The opposing portions 321 and 322 are surfaces that entirely face the rear surfaces of the end portions 621 and 622 , and therefore magnetic flux can flow efficiently between the opposing portions 321 and 322 and the rear surfaces of the end portions 621 and 622 .

[0060] The facing portions 321, 322 are preferably made of a ferromagnetic material, such as iron (Fe), cobalt (Co), nickel (Ni), gadolinium (Gd), etc., as part of the base main body 31. The facing portions 321, 322, together with the spring connecting portions 341, 342 and the fixing portion 36, are made of a metal material (such as iron), such as iron, cobalt, or nickel, as part of the base main body 31.

[0061] Both end portions 621, 622 are arranged above (in the Z direction) the opposing portions 321, 322, spaced apart and facing each other, and are symmetrical about the center in the X direction. Furthermore, except for the position of the wiring portion 84 of the substrate 80, the portions are formed symmetrical about the center in the Y direction. The spring connection portions 341, 342 are arranged to sandwich the opening 38 in the X direction, and are joined to the base portion-side fixing portions 441, 442 of the plate-shaped elastic portion 40 on the front surface side of the base portion 30.

[0062] The fixing portions 36 are, for example, fastening holes that fasten the base portion 30 to an operating device (vibration presentation unit) that an operator touches and operates, or to a housing (arrangement unit) on which the operating device is disposed, via a fastening member. The fixing portions 36 are formed at the four corners of the base portion 30, allowing the base portion 30 to be securely fastened and fixed to a fixed object. Although the fixing portions 36 are formed at the four corners, any number of fixing portions 36 may be provided as long as the base portion 30 can be fixed to the fixed object. One of the fastening holes serving as the fixing portion 36 may be an elongated hole (see fixing portion 36a shown in FIGS. 2 and 8). The vibration actuator 10 is fixed to a fixed portion by placing the fixing portion 36 in a corresponding position and inserting a fastening member such as a screw into the fixing portion 36 to fasten it to the fixed portion. In this case, the fastening member can be passed through the fixing portions 36 other than the elongated hole (particularly the fixing portions diagonal to the elongated hole) and then fastening it with the fastening member through the elongated hole. This allows the vibration actuator 10 to be fixed in a predetermined position, even if there is some error, and the error can be absorbed to ensure proper fixation. Furthermore, one of the corners of the plate part 30 on which the fixing part 36 is arranged may be formed as a chamfered corner 301 (e.g., a C-surface) (see FIG. 2). This makes it possible to visually confirm the orientation of the vibration actuator 10 during assembly, and allows for proper assembly work, including wiring, to be carried out.

[0063] <Plate-shaped elastic portion 40> Specifically, the plate-shaped elastic portion 40 is an elastically deformable leaf spring, and supports the movable portion 20 movably in the thickness direction (Z direction) relative to the base portion 30. The plate-shaped elastic portion 40 is formed in the shape of a thin plate frame having a predetermined thickness (thickness in the Z direction), and is arranged in a layered form between the base portion 30 and the movable portion 20 in the thickness direction (Z direction).

[0064] The plate-shaped elastic portion 40 is connected to each of the movable portion 20 (specifically, the core body 60) and the base portion 30, and joins the plate-shaped movable portion 20 (core body 60) and the plate-shaped base portion 30 with a thickness separation therebetween, i.e., with a gap G (see Figure 7) provided.

[0065] The plate-shaped elastic member 40 also has a pair of parallel sides 461 that form a frame-like body surrounding the base member 30, and another pair of opposing sides 462 that are adjacent to the pair of sides 461. Each of the pair of sides 461 is joined to spring connection parts 631, 632 of the movable member 20 via movable member-side fixed parts 421, 422. On the other hand, the other pair of sides 462 are connected to spring connection parts 341, 342 of the base member 30 via base member-side fixed parts 441, 442.

[0066] The plate-shaped elastic member 40 has an elastic main body 46 including an elastically deformable arm that connects the movable-part-side fixed parts 421, 422 and the base-part-side fixed parts 441, 442. The arm is formed, for example, in an L-shape, so as to have a frame shape that surrounds the base part 30 in a plan view, and is deformable in the Z direction on the outer periphery of the base part 30.

[0067] In addition, in the elastic main body portion 46, the movable part side fixing portions 421, 422 and one side portion of the L-shaped arm that is linearly connected to the movable part side fixing portions 421, 422 form a pair of parallel sides 461, and the other pair of sides 462 adjacent to this pair of sides 461 have base part side fixing portions 441, 442 formed so as to protrude inward.

[0068] In the plate-shaped elastic part 40, the elastic main body part 46 includes movable part side fixing parts 421, 422 and is connected to base part side fixing parts 441, 442, and the elastic main body part 46, movable part side fixing parts 421, 422 and base part side fixing parts 441, 442 are arranged on the same plane.

[0069] The plate-shaped elastic portion 40 supports the movable portion 20 (specifically, the core body 60) in a symmetrical and balanced manner in directions (X direction and Y direction) perpendicular to the direction facing the base portion 30 (vibration direction) relative to the base portion 30.

[0070] The movable unit side fixing portions 421, 422 are planar and are provided at the center of a pair of sides of the elastic main body 46 that are located outside the base unit 30 in a plan view. The surfaces of the movable unit side fixing portions 421, 422 are fixed in surface contact with the back surfaces of the spring connection portions 631, 632 of the core 62. The movable unit side fixing portions 421, 422 are provided symmetrically in each direction with respect to the center in the X direction or the center in the Y direction. The base unit side fixing portions 441, 442 are planar and are fixed in a stacked state to the spring connection portions 341, 342 of the base unit 30.

[0071] The base-side fixing portions 441, 442 and the spring connecting portions 341, 342 may be fixed using fastening members such as screws or bolts, adhesives, or the like. Alternatively, they may be joined and fixed via a recessed portion and a protruding portion formed on each of the spring connecting portions 341, 342 that can fit together. For example, the spring connecting portions 341, 342 may be provided with a convex boss portion (protrusion) 56 that protrudes toward the base-side fixing portions 441, 442, and the base-side fixing portions 441, 442 may be provided with a joining hole 47 at a position corresponding to the boss portion 56. The joining hole 47 may be an elongated hole into which a portion of the boss portion 56 is fitted. The joining hole 47 has the boss portion 56 disposed therein, which functions to position the base-side fixing portions 441, 442 relative to the base portion 30 and also secures the boss portion 56 that is press-fitted.

[0072] When the boss portion 56 is press-fitted into the joining hole 47, the two are fixed by adhesive or laser welding. A groove is formed around the base of the boss portion 56, and this groove functions as an adhesive reservoir when adhesive is used. The groove also functions as an escape for scraps and scum that are generated when the boss portion 56 is press-fitted into the joining hole 47. The groove is formed as an escape portion for the R-shaped base of the boss portion 56 when machining the boss portion 56 into the base portion 30.

[0073] Since the plate-shaped elastic part 40 is a rectangular frame (here, a thin plate frame), it is possible to reduce the number of parts and make the entire product thinner, and further, it can be manufactured without bending parts, etc. Furthermore, since it is a frame, other parts can be arranged inside the frame so as not to interfere with them.

[0074] As will be described later, the plate-shaped elastic portion 40 has a spring constant K ｓｐ By setting the above, the amount of displacement and natural frequency of the movable part 20 can be determined, and when the movable part 20 is driven, that is, when current is passed through the coil 50, a displacement occurs, which creates a mechanical tactile sensation.

[0075] The plate-shaped elastic portion 40 has arms of the elastic main body portion 46 to ensure elasticity, and the shape of these arms may be any shape as long as they connect the movable portion side fixing portions 421, 422 and the base portion side fixing portions 441, 442 so as to be displaceable in the Z direction. Furthermore, the elastic main body portion 46 may have any shape as long as it is formed to deform in a balanced manner so as to move the core body 60 in the Z direction (vibration applying direction) while the core body 60 is positioned on the XY plane.

[0076] The plate-shaped elastic part 40 deforms between the upper surface of the core 62 or the coil 50 and the bottom surface of the base part 30. In this way, the plate-shaped elastic part 40 is formed in a rectangular frame shape, and movable part-side fixed parts 421, 422 and base part-side fixed parts 441, 442 are disposed at the center of each side of the rectangular frame. When the core body 60 is driven, the movable part-side fixed parts 421, 422 are displaced relative to the base part-side fixed parts 441, 442.

[0077] The core body 60 is supported on both sides of the elastic main body 46 by L-shaped arms that connect the movable part side fixing parts 421, 422 and the base part side fixing parts 441, 442. This allows stress dispersion during elastic deformation, and the core body 60 can be moved in the vibration direction (Z direction) without tilting relative to the base part 30, thereby improving the reliability and stability of the vibration state.

[0078] <Magnetic Circuit of Vibration Actuator 10> Fig. 14 is a diagram illustrating the drive circuit of the vibration actuator. Note that Fig. 14 is a cross-sectional view of the vibration actuator 10 shown in Fig. 7, and the magnetic circuit has magnetic flux flow M in parts not shown that is similar to that in the parts shown.

[0079] 14, the core 62 is excited to generate a magnetic field, and both ends 621, 622 of the core 62 become magnetic poles. For example, if one end 621 of the core 62 becomes an N pole and the other end 622 becomes an S pole, a magnetic circuit indicated by magnetic flux flow M is formed between the core 62 and the opposing parts 321, 322 of the base part 30.

[0080] The flow of magnetic flux M in this magnetic circuit flows from one end 621 to the opposing opposing portion 321, from the opposing portion 321 to the opposing portion 322, from the opposing portion 322 to the other end 622 of the core 62, passes through the core 62 and is emitted again from the one end 621.

[0081] As a result, in accordance with the principle of an electromagnetic solenoid, both end portions 621, 622 of core 62 generate a magnetic attraction force KR. That is, in the electromagnet, magnetic attraction force KR is generated in a direction perpendicular to the winding axis of coil 50, and both end portions 621, 622 are attracted to both opposing portions 321, 322 of base portion 30.

[0082] Because the base unit 30 is fixed to a housing or the like via the fixing unit 36, the opposite end portions 621, 622 are attracted to and adsorbed to the opposing portions 321, 322. In other words, the plate-shaped elastic member 40 is deformed, and the movable unit 20 is attracted toward the base unit 30. The movable unit 20 moves closer to the position where the base unit 30 is fixed (in the −Z direction).

[0083] Next, when the power supply to the coil 50 is cut off, the magnetic field disappears, the magnetic attraction force KR of the movable part 20 disappears, and the biasing force of the plate-shaped elastic part 40, which has deformed toward the base part 30, is released. That is, a spring reaction force (force in the -KR direction) is generated as the plate-shaped elastic part 40. As a result, the reaction force (-KR) of the plate-shaped elastic part 40 causes the movable part 20 to move (in the +Z direction, opposite the attraction direction of the magnetic attraction force KR) back to its original position (the position in a non-driven stationary state, which is the reference position as shown in FIG. 7 ) due to the reaction force (-KR). At this time, the movable part 20 moves due to the reaction force (-KR) to a position displaced away from the base part 30 from the stationary position, generating strong vibrations.

[0084] This vibration decays as the biasing force decays, and the vibrations decay and repeat as free vibrations. Alternatively, the coil 50 may be energized and deenergized repeatedly to cause the movable part 20 to move back and forth in the Z direction, thereby generating vibrations. In this manner, in the vibration actuator 10, the movable part 20 is supported in a state in which it is suspended from the base part 30 by the plate-shaped elastic part 40. When energized, the movable part 20 functions as an electromagnet, and is mechanically displaced by the magnetic attraction force generated between the movable part 20 and the opposing parts 321, 322, which are magnetic bodies, and then undergoes free vibrations.

[0085] In this way, the vibration actuator 10 moves the movable part 20 toward the base part 30 by the magnetic attraction force generated between the core 62 and the opposing parts (magnetic bodies) 321, 322 when current is applied to the coil 50. This movement of the movable part 20 causes vibration of the movable part 20 due to the elastic force (biasing force) generated in the plate-shaped elastic part 40, giving the user a tactile sensation.

[0086] In the vibration actuator 10, the coil 50 is plate-shaped and is wound around a thin plate-shaped core 62 via a sheet-shaped insulating part 822 of the substrate 80 that is connected to the coil 50. Furthermore, the core 62 is supported by the plate-shaped elastic part 40 so as to be movable in the Z direction relative to the base part 30, with the coil 50 inserted through the opening 38 of the thin plate-shaped base part 30.

[0087] The vibration actuator 10 can be configured only by the height obtained by stacking the thin plate-like core 62, the plate-shaped weight portion 70 or the coil 50, the plate-shaped elastic portion 40, and the base portion 30. When the plate-shaped weight portion 70 is included as an element that constitutes the stacked height in the vibration actuator 10, this is the case when the upper surface of the portion of the coil 50 on the core 62 is lower than the upper surface of the plate-shaped weight portion 70. On the other hand, when the coil 50 is included as an element that constitutes the stacked height in the vibration actuator 10, this is the case when the upper surface of the coil 50 is higher than the upper surface of the plate-shaped weight portion 70, or when the vibration actuator 10 does not have a plate-shaped weight portion 70.

[0088] The vibration actuator 10 is configured as a thin plate that vibrates without a magnet, allowing for a low profile and space-saving installation. In other words, the configuration of the vibration actuator 10 is even thinner than a configuration in which components that generate magnetism and drive a movable part in the Z direction are stacked in the Z direction, such as a coil and a magnet that are arranged opposite each other in the Z direction. The vibration actuator 10 can be made thinner and smaller, and can provide a suitable tactile sensation that corresponds to the user's pressing operation on the vibration presentation part.

[0089] In this way, in a vibration actuator 10 that has been made thinner and smaller, the coil 50 can be arranged in an insulated state from the core 62 using a substrate 80 that is attached to the core 62 to supply power to the coil 50, without using a separate insulating member to insulate the coil 50 from the core 62.

[0090] <Driving principle of vibration actuator 10> The following briefly describes the driving principle of the vibration actuator 10. The vibration actuator 10 can also be driven by generating a resonance phenomenon using pulses using the following equations of motion and circuit equations. Note that the operation does not have to be resonance driving, and it may be, for example, a device that expresses the operational feel of a track pad as the vibration presentation device 100 shown in FIG. 17, and may be driven by inputting a current pulse (which may be single or multiple) via a control unit (not shown).

[0091] The movable portion 20 of the vibration actuator 10 performs reciprocating motion based on the equations (1) and (2).

[0092]

[0093]

[0094] That is, the mass m [kg], the displacement x(t) [m], 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 (1). 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 a range that satisfies formula (2).

[0095] In this way, the vibration in the vibration actuator 10 is determined by the mass m of the movable part 20 and the spring constant Ksp of the metal spring (a leaf spring in this embodiment) serving as the plate-shaped elastic part 40. Furthermore, the vibration generated by the vibration actuator 10 can be set by the input voltage (pulse) and, if a vibration damping part is provided, the degree of damping of the vibration damping part.

[0096] <Assembly of Core Body 60> Figure 15 is a diagram illustrating a method for assembling the movable portion. The core body 60 is assembled using, for example, a jig 500 shown in Figure 15. The jig 500 includes a base 510 and support columns 521 to 524 mounted on a main body plate 501. The base 510 has a mounting surface 512 on which the core 62 is mounted. The support columns 521 and 522 are positioned so that the center of the core 62 is positioned on the mounting surface 512 when inserted into the spring connection sections 631 and 632. The support columns 523 and 524 are positioned corresponding to the positioning holes 831 in the substrate 80. By inserting the support columns 521 and 522 into the spring connection sections 631 and 632 of the core 62, the center of the core 62 is positioned on the mounting surface 512. In this state, the substrate 80 is brought close to the core 62 from above, and the support posts 523, 524 are inserted into the positioning holes 831. As a result, the substrate 80 can be attached to the core 62 in an accurate position by placing the front surface covering portion 823 on the center of the core 62 in a perpendicular state and fixing it with double-sided tape or the like, and then wrapping the back surface covering portion around the back side of the core 62 to cover the back surface of the core 62.

[0097] <Drive Circuit of Vibration Actuator 10> FIG. 16 is a diagram showing the circuit configuration of the control section of the vibration actuator according to the first embodiment.

[0098] The drive circuit shown in Fig. 16 is included in the control unit of the vibration actuator 10. The drive circuit has a switching element 12 as a current pulse supply unit configured using a MOSFET (metal-oxide-semiconductor field-effect transistor), a signal generation unit 14 as a voltage pulse application unit, resistors R1 and R2, and SBDs (Schottky Barrier Diodes). This drive circuit is an example of a specific configuration of an actuator driver.

[0099] A signal generating unit 14, which is connected to a power supply voltage Vcc, is connected to the gate of a switching element 12. The switching element 12 is a discharge switch. The switching element 12 is connected to a vibration actuator 10 (shown as [Actuator] in FIG. 15 ), and in particular to a signal generating unit 14 of the vibration actuator 10. A voltage is applied to the vibration actuator 10 from a power supply unit Vact. Thus, the switching element 12 is turned on and off by gate voltage control by the signal generating unit 14, and when the switching element 12 is turned on, a current flows, and electricity is applied to a coil 50, which functions as a vibration generating unit in the vibration actuator 10.

[0100] The control unit may include an arithmetic processing unit including a central processing unit (CPU) and other components that controls the entire vibration presentation device in which the vibration actuator 10 is implemented; a main storage device including a random access memory (RAM) and other components that serves as the work area of ​​the arithmetic processing unit; and an auxiliary storage device including a non-volatile memory such as a flash memory or a hard disk that stores the operating programs of the arithmetic processing unit. A configuration including the arithmetic processing unit, the main storage device, and the auxiliary storage device is an example of a specific configuration of a microcomputer. The arithmetic processing unit reads various control programs and various data associated with the programs (hereinafter, the various control programs and various data are collectively referred to as "programs") from the auxiliary storage device and stores them in the main storage device. The control program executes the control programs using the data and realizes various functions of the vibration presentation device. For example, the data may include pulse waveform data of various patterns representing multiple different vibration damping periods or multiple different vibration intensities. The various control programs may include a program that, when information indicating an operator's touch operation is input, reads pulse waveform data for generating an actuator drive signal that generates vibrations corresponding to the input information, and generates the actuator drive signal according to the read pulse waveform data.

[0101] The auxiliary storage device may be a storage medium that is detachable from the vibration presentation device. The control unit may be configured to communicate with the outside, so that programs and the like can be downloaded from the outside to the control unit (main storage device or auxiliary storage device) via a communication network. The main storage device and auxiliary storage device described above are examples of non-transitory computer-readable storage media.

[0102] <Vibration Presentation Device 100> Fig. 17 is a diagram showing an example of a vibration presentation device having a vibration actuator. For convenience, in Fig. 17, the planar track pad body that an operator presses with his / her finger is shown as transparent.

[0103] The vibration presentation device 100 is, for example, a trackpad serving as a pointing device used in place of a mouse in a laptop computer, etc. The trackpad serving as the vibration presentation device 100 is placed in a rectangular opening provided in the housing of the laptop computer, etc. The trackpad has a plate-shaped pad body 110 that is traced with a finger for touch operation, a vibration actuator 10 placed on the back surface of the pad body 110, and a frame 130 that surrounds the vibration actuator 10.

[0104] In the trackpad, the vibration actuator 10 applies vibrations that provide a tactile sensation when the user performs contact operations such as tracing or tapping the pad body 110 with a finger. Specifically, in the vibration actuator 10, current is passed through the coil 50 in response to the user's contact with the pad body 110, which is the operation surface, causing the coil 50 to displace closer to the base portion 30 and vibrate, thereby providing the user with a tactile sensation. For example, the pad body 110 is fixed at the back side of its central portion to the movable portion 20 of the vibration actuator 10 with double-sided tape or the like. The vibration actuator 10 is fixed to the bottom surface of the frame portion 130 via the base portion 30. Furthermore, the outer periphery of the pad body 110 is movably attached to the frame body 130 via a buffer member.

[0105] Furthermore, in the vibration actuator 10, the base portion 30 and the plate-shaped elastic portion 40, and the plate-shaped elastic portion 40 and the movable portion 20 are joined together using a fastening member such as an adhesive or welding. Screws may also be used as fastening members.

[0106] (Embodiment 2) Fig. 18 is an external perspective view of a vibration actuator according to embodiment 2 of the present invention, Fig. 19 is a plan view of the same vibration actuator, and Fig. 20 is a bottom view of the same vibration actuator. Also, Figs. 21A and 21B are front and rear views of the same vibration actuator, Figs. 22A and 22B are right and left side views of the same vibration actuator, and Fig. 23 is an exploded perspective view of the vibration actuator according to embodiment 2 of the present invention. Also, Fig. 24 is a perspective view showing the core body of the vibration actuator according to embodiment 2 of the present invention with the coil removed, and Fig. 25 is an exploded perspective view of the core body.

[0107] 18 to 25, vibration actuator 10A according to embodiment 2 is different from vibration actuator 10 corresponding to embodiment 1 shown in Fig. 1 only in the configuration of substrate 80A in core body 60A, but otherwise is similar in configuration. In the following, in vibration actuator 10A according to embodiment 2, parts that are similar to vibration actuator 10 according to embodiment 1 are given the same reference numerals, and the explanation will focus on the differences.

[0108] In the vibration actuator 10A, the substrate 80A, which is the flexible substrate of the core body 60A, has a heat dissipation (heat absorption) function in addition to the insulating function of insulating the core 62 from the coil 50. That is, in the core body 60A of the movable part 20A, the substrate 80A has a heat dissipation section 90 in addition to the wiring section 84 and the insulating section 822A on the insulating sheet 82A.

[0109] The heat dissipation section 90 is disposed on the insulating section 822A and dissipates heat generated by the coil 50. The heat dissipation section 90 is a film-like or plate-like body made of a thermally conductive material, and is formed of copper foil disposed over the entire surface of the surface covering section 823A of the insulating section 822A.

[0110] This copper foil is not provided with a coverlay, and one end of the copper foil extends from the portion of the core 62 surrounded by the coil 50 and is exposed to the outside. This copper foil functions as a heat sink. In the core body 60A, the heat dissipation portion 90 made of copper foil is disposed on the core 62 between the surface covering portion 823A of the insulating sheet 82A and the coil 50.

[0111] Surface covering portion 823A is formed larger on the one end 6220 side than the area covered by coil 50, and heat dissipation portion 90 is disposed over the entire surface of surface covering portion 823A. Heat dissipation portion 90 is disposed between insulating sheet 82A (or core 62) and coil 50 on the opposite side to wiring portion 84 (one end 6220 side) so as to have a protruding portion (extending portion) 902 that protrudes outward from coil 50.

[0112] This protrusion 902 functions as a heat sink, so that even if the coil 50 generates heat when the vibration actuator 10A is driven, the heat can be efficiently dissipated from the inside of the coil 50 to the outside of the coil 50, allowing the vibration actuator 10A to be driven appropriately.

[0113] <Other Modifications> The following other modifications are formed by partially changing or adding to the configuration of the vibration actuator 10 described above, and when they have the same functions as the components described above, they are given the same names and reference numerals and their explanations are omitted. Furthermore, for convenience, the components described above will be referred to by different names below.

[0114] <Modification 1> Fig. 26 is a plan view of a vibration actuator of Modification 1, and Fig. 27 is a bottom view of the vibration actuator of Modification 1. Also, Figs. 28A and 28B are a front view and a rear view of the vibration actuator of Modification 1, and Figs. 29A and 29B are a right side view and a left side view of the vibration actuator of Modification 1.

[0115] In the vibration actuator 10B of Modification 1, in the configuration of the vibration actuator 10 (see FIGS. 1 to 14), an external connection part 92 that relays connection with an external device is connected from the flat side to the wiring part 84 of the substrate 80. The external connection part 92 is made of a flexible substrate and is formed in an L-shape along part of the outer edge of the vibration actuator 10B, and is arranged so that it does not come into contact with the movable part 20, base part 30B, etc. at points other than the connection part. The external connection part 92 has a wiring part connection part 922 at one end and an external connection terminal part 924 at the other end.

[0116] Furthermore, the base portion 30B is provided with a matrix of recesses 37. The matrix of recesses 37 forms an uneven portion on the base portion 30B, which increases the adhesive area when fixing the base portion 30B to a housing or the like, thereby enabling a stronger fixation. Note that, although the base portion 30B is configured to have a plurality of recesses 37 to increase the adhesive area, this is not limiting, and protrusions may be provided instead of the recesses 37 to increase the adhesive area when fixing to a fixing object such as a housing by adhesive.

[0117] <Modification 2> Fig. 30 is a plan view of a vibration actuator of Modification 2, and Fig. 31 is a bottom view of the vibration actuator of Modification 2. Also, Figs. 32A and 32B are a front view and a rear view of the vibration actuator of Modification 2, and Figs. 33A and 33B are a right side view and a left side view of the vibration actuator of Modification 2.

[0118] The vibration actuator 10C of the second modification has a configuration in which a fixing plate 94 is attached to the base 30B of the vibration actuator 10B of the first modification. The fixing plate 94 is formed in the shape of a rectangular plate with an opening 942 in the center, and has an extension 944 that extends outward along the base 30B.

[0119] The coil 50 is highly conductive and is made of, for example, copper. The core 62 is made of a material with high magnetic permeability (a ferromagnetic material, simply referred to as a magnetic material), and is preferably made of SECC, silicon steel plate, SUS, or the like. The plate-shaped elastic portion 40 is preferably a non-magnetic material, and SUS, phosphor bronze, resin, rubber, or the like may be used as the non-magnetic material constituting the plate-shaped elastic portion and the elastic body. The base portions 30, 30A-30B are preferably made of a material with high magnetic permeability, such as SECC, silicon steel plate, SUS (ferromagnetic SUS), or the like. The plate-shaped weight portion 70 is made of a material with a high specific gravity, such as phosphor bronze, SUS, tungsten, or the like.

[0120] Although vibration actuators 10, 10A, 10B, and 10C are used in this embodiment, actuators 10, 10A, 10B, and 10C having similar configurations may also be used.

[0121] The embodiments of the present invention have been described above. Note that the above description is an example of a preferred embodiment of the present invention, and the scope of the present invention is not limited to this. In other words, the description of the configuration of the above device and the shape of each part is one example, and it is clear that various modifications and additions to these examples are possible within the scope of the present invention.

[0122] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2023-141710, filed on August 31, 2023, are incorporated herein by reference in their entirety.

[0123] The vibration actuator and contact-type input device of the present invention have the advantages of being easier to assemble, being thinner, and being able to vibrate favorably, and are useful as vibration presentation devices for contact-type input devices such as track pads and operation panels.

[0124] 10, 10A, 10B Vibration actuator 12 Switching element 14 Signal generating unit 20, 20A Movable unit 30 Base unit, 30A, 30B Base unit 31 Base main body unit 36 ​​Fixed unit 37 Recessed portion 38 Opening 40 Plate-shaped elastic unit (elastic support unit) 46 Elastic main body unit 50 Coil 55 Fastening member 60, 60A Core body 62 Core 68 Protective film unit 70 Plate-shaped weight unit 72, 74 Opening 80, 80A Substrate 82, 82A Insulating sheet 84 Wiring unit 85 Coil wiring land unit 86 External connection land unit 90 Heat dissipation unit 92 External connection unit 94 Fixing plate unit 100 Vibration presentation device 110 Pad main body 130 Frame unit 311 Side unit (X-side unit) 312 Side portion (Y side portion) 321, 322 Opposing portion 341, 342 Spring connection portion 421, 422 Movable portion side fixed portion 441, 442 Base portion side fixed portion 461, 462 Side portion 621 One end portion 622 Other end portion 629 Edge portion 631, 632 Spring connection portion 821 Part 822, 822A Insulating portion 823 Surface covering portion 824, 825 Back covering portion 826 Bendable portion 831 Hole 922 Wiring portion connecting portion 924 External connection terminal portion

Claims

1. A vibration actuator comprising: a core; a coil arranged around the core; and a substrate arranged on the core and integrally comprising a wiring portion connected to the coil and an insulating portion arranged inside the coil to insulate the coil from the core.

2. A vibration actuator as described in claim 1, wherein the core is a plate-like body, and the insulating portion is sheet-like and is arranged inside the coil by being wound around the core to cover it.

3. A vibration actuator as described in claim 1, wherein the wiring portion has a thickness greater than that of the insulating portion on the core and is provided adjacent to the insulating portion on the core, and the coil is disposed on the insulating portion adjacent to the wiring portion.

4. The vibration actuator according to claim 1, wherein the insulating portion has a heat dissipation portion.

5. A vibration actuator according to claim 4, wherein the heat dissipation portion has a protrusion that protrudes outward from between the coil and the core.

6. A vibration actuator as described in claim 1, comprising: an electromagnet having a substrate and a coil disposed in the center of the core; plates having magnetic bodies disposed opposite both ends of the core; and elastic support parts supporting the core on both sides of the coil and connected to the plate, wherein a magnetic force generated by passing current through the coil via the substrate displaces one of the coil or the plate so that it approaches the other and vibrates.

7. The vibration actuator according to claim 1, further comprising a frame-shaped weight portion attached to said core and having openings in the area of ​​said coil and the area of ​​said wiring portion.

8. A contact-type input device in which the vibration actuator according to claim 6 is disposed on the reverse side of an operation surface, wherein current is passed through the coil in response to a user's touch on the operation surface, and one of the coil or the plate is displaced and vibrates so as to approach the other, thereby providing a tactile sensation to the user.

Images