Vibration generation device

Abstract

A vibration generation device (101) comprises: a fixed body (FB); a movable body (MB); and a support member (7) that supports the movable body (MB) in a manner capable of vibrating along the Y-axis direction with respect to the fixed body (FB). The fixed body (FB) includes a coil (4) which has a bundle wire part (4S) including a plurality of conductive wires extending in the X-axis direction, and which is disposed on the lower side of the movable body (MB). The movable body (MB) includes a permanent magnet (5) that generates a first magnetic flux (MF1) which is oriented downward and a second magnetic flux (MF2) which is oriented upward. The fixed body (FB) includes a conductive plate-like member (3) that is disposed on the upper side of the movable body (MB), that extends along the Y-axis direction so as to intersect the second magnetic flux (MF2), and that generates an eddy current when the movable body (MB) has moved in the Y-axis direction.

Description

Vibration Generator

[0001] The present disclosure relates to a vibration generating device.

[0002] Conventionally, an actuator (vibration generator) that generates vibrations has been known (see Patent Document 1). This actuator is configured to suppress resonance when the movable body is vibrated by using a gel damper member disposed between a support body and a movable body.

[0003] Japanese Patent Application Laid-Open No. 2019-013086

[0004] However, the gel damper member described above may have durability problems, so it is desirable to provide a vibration generator having a durable structure that can suppress resonance.

[0005] A vibration generating device according to an embodiment of the present disclosure is a vibration generating device comprising: a fixed body, a movable body, and a support member that supports the movable body relative to the fixed body so that the movable body can vibrate along a first direction, wherein the fixed body has a wire bundle section including a plurality of conductors extending in a second direction perpendicular to the first direction, and includes a coil arranged on one side of the movable body in a third direction perpendicular to the first direction and the second direction, the movable body includes a permanent magnet that generates a first magnetic flux directed toward the wire bundle section and a second magnetic flux directed toward the opposite side of the wire bundle section, and the fixed body is arranged on the other side of the movable body in the third direction, and includes a conductive plate-like member that extends along the first direction so as to intersect with the second magnetic flux, and in which eddy currents are generated when the movable body moves in the first direction.

[0006] The vibration generator described above has a highly durable structure that can suppress resonance.

[0007] 1 is a diagram illustrating an example of the configuration of a vibration generator; FIG. 2 is an exploded perspective view of a vibration generator; FIG. 3 is a six-view diagram of a support member; FIG. 4 is a perspective view of a movable body and a support member; FIG. 5 is a front view and a bottom view of the movable body and the support member; FIG. 6 is a top view and a cross-sectional view of a vibration generator; FIG. 7 is a top view of a coil, a movable body, and a support member; FIG. 8 is a front view of a conductive plate-shaped member, a coil, a movable body, and a support member; FIG. 9 is a cross-sectional view of a vibration generator;

[0008] Hereinafter, a vibration exciter 101 according to an embodiment of the present disclosure will be described with reference to the drawings. Fig. 1 is a diagram showing an example of the configuration of the vibration exciter 101. Specifically, the upper diagram of Fig. 1 is a perspective view of the vibration exciter 101, and the lower diagram of Fig. 1 is an exploded perspective view of the vibration exciter 101. Fig. 2 is a more detailed exploded perspective view of the vibration exciter 101.

[0009] In each of FIGS. 1 and 2 , X1 represents one direction of the X axis constituting a three-dimensional orthogonal coordinate system, and X2 represents the other direction of the X axis. Furthermore, Y1 represents one direction of the Y axis constituting the three-dimensional orthogonal coordinate system, and Y2 represents the other direction of the Y axis. Similarly, Z1 represents one direction of the Z axis constituting the three-dimensional orthogonal coordinate system, and Z2 represents the other direction of the Z axis. In this embodiment, the X1 side of the vibration generator 101 corresponds to the front side (front face side) of the vibration generator 101, and the X2 side of the vibration generator 101 corresponds to the rear side (rear face side) of the vibration generator 101. Furthermore, the Y1 side of the vibration generator 101 corresponds to the left side of the vibration generator 101, and the Y2 side of the vibration generator 101 corresponds to the right side of the vibration generator 101. The Z1 side of the vibration generator 101 corresponds to the upper side of the vibration generator 101, and the Z2 side of the vibration generator 101 corresponds to the lower side of the vibration generator 101. The same applies to the other figures.

[0010] The vibration device VE includes a control unit CTR and a vibration generator 101. The vibration generator 101 is inserted into a thin, tubular object, such as a stylus, and is positioned so as to vibrate in the radial direction (short direction) of the object. Therefore, the vibration generator 101 is preferably configured so that its length in the vibration direction is as small as possible while still achieving the desired vibration power. Specifically, the vibration generator 101 includes a housing HS as a box-shaped case, a movable body MB housed within the housing HS, a conductive plate member 3 attached to the housing HS, and a coil 4 attached to the housing HS via an insulating substrate BM. The housing HS, the conductive plate member 3, and the coil 4 form a fixed body FB. The control unit CTR is connected to an input terminal IT provided on the insulating substrate BM, which is fixed to the housing HS via adhesive. In this embodiment, the insulating substrate BM is a combination of a flexible substrate and a rigid substrate. However, the insulating substrate BM may also be a flexible substrate or a rigid-flexible substrate. In the upper diagram of FIG. 1, the dashed line connecting the control unit CTR and the input terminal IT provided on the insulating substrate BM schematically indicates that the control unit CTR and the input terminal IT are electrically connected.

[0011] As shown in the upper diagram of Fig. 1 , the housing HS has a substantially rectangular parallelepiped outer shape and is configured so that the areas of the surfaces parallel to the XY plane (top and bottom surfaces) are larger than the other surfaces. In this embodiment, the housing HS is configured with a cover 1 and a base plate 2. The cover 1 is made of a non-magnetic metal such as austenitic stainless steel. However, the cover 1 may also be made of synthetic resin or magnetic metal.

[0012] In the illustrated example, as shown in the lower diagram of FIG. 1 , the cover 1 is configured by bending a single metal plate to form five surfaces (top, front, left, rear, and right surfaces) of the housing HS. Specifically, the cover 1 includes a cylindrical portion 1A having a substantially rectangular cylindrical shape and a top plate portion 1B having a substantially rectangular flat plate shape. The cylindrical portion 1A includes a front plate portion 1A1, a left plate portion 1A2, a rear plate portion 1A3, and a right plate portion 1A4. More specifically, the cylindrical portion 1A includes a front plate portion 1A1 and a rear plate portion 1A3 that face each other, and a left plate portion 1A2 and a right plate portion 1A4 that are perpendicular to the front plate portion 1A1 and the rear plate portion 1A3 and face each other.

[0013] The base plate 2 is configured to form the lower surface (bottom surface) of the housing HS. In this embodiment, the base plate 2 forms a bottom plate portion in the shape of a substantially rectangular flat plate. In the illustrated example, the base plate 2 is formed of a magnetic metal and functions as a fixed-side magnetic member. The base plate 2 as a fixed-side magnetic member is configured to be able to control the path of the magnetic field lines of the magnetic field generated by the permanent magnet 5 as a movable-side magnetic field generating member. Furthermore, the base plate 2 as a fixed-side magnetic member is a member that constitutes the driving means DM. However, the base plate 2 may also be formed of a non-magnetic metal such as austenitic stainless steel.

[0014] The cover 1 is fixed to the base plate 2. Specifically, the cover 1 is joined to the base plate 2 by welding the lower end of the cylindrical portion 1A to the base plate 2. The lower end of the cylindrical portion 1A and the base plate 2 may be joined by brazing, an adhesive, caulking, or the like. The insulating substrate BM is joined to the upper surface of the base plate 2 by an adhesive.

[0015] The conductive plate member 3 is fixed to the ceiling surface of the cover 1 by double-sided tape, adhesive, crimping, etc. In the illustrated example, the conductive plate member 3 is a copper plate, and is fixed to the ceiling surface of the cover 1 by double-sided tape. The conductive plate member 3 may also be formed of a material containing copper or aluminum.

[0016] The coil 4 is an example of a fixed magnetic field generating member, and is configured to be able to generate a magnetic field while being fixed to the housing HS. The coil 4 is also a component constituting the driving means DM. In this embodiment, the coil 4 is a wound coil formed by winding a conductor whose surface is coated with an insulating material, and is fixed to the insulating substrate BM with adhesive. Note that for clarity, Figures 1 and 2 omit detailed illustration of the winding state of the conductor. This also applies to other figures that illustrate the coil 4.

[0017] Specifically, as shown in the lower diagram of Figure 1, the coil 4 is arranged so that one end (first end 4A) is connected to a first conductor pad PD1 formed on the upper surface of the insulating substrate BM, and the other end (second end 4B) is connected to a second conductor pad PD2 formed on the upper surface of the insulating substrate BM.

[0018] The control unit CTR is configured to control the movement of the movable body MB. In this embodiment, the control unit CTR is a device including an electronic circuit, a nonvolatile memory device, etc., and is configured to control the direction and magnitude of the current flowing through the coil 4. The control unit CTR may be configured to control the direction and magnitude of the current flowing through the coil 4 in response to a control command from an external device such as a computer, or may be configured to control the direction and magnitude of the current flowing through the coil 4 without receiving a control command from an external device. In other words, the control unit CTR may be a microcomputer equipped with a CPU. Note that, although the control unit CTR is installed outside the housing HS in this embodiment, it may also be installed inside the housing HS.

[0019] The movable body MB is configured to be able to vibrate the housing HS. In this embodiment, the movable body MB is configured to be able to vibrate the housing HS by reciprocating while being attached inside the housing HS via the support member 7.

[0020] Specifically, the movable body MB includes a permanent magnet 5 and a plate-shaped metal member 6, and is configured to be elastically supported by a support member 7. More specifically, the movable body MB has a predetermined natural frequency and is configured to be able to reciprocate (vibrate) relative to the housing HS along a vibration axis VA (see the lower diagram in FIG. 1 ) extending in a predetermined direction (the Y-axis direction).

[0021] The permanent magnet 5 is configured to generate a magnetic field while being capable of reciprocating (vibrating) relative to the housing HS. The permanent magnet 5 is also a component constituting the driving means DM. In this embodiment, the permanent magnet 5 includes a left-side magnet 5L and a right-side magnet 5R that are magnetized into two poles in the Z-axis direction, as shown in FIG. 2 . For clarity, in FIG. 2 , a cross pattern is applied to the south pole portion of the permanent magnet 5, and a dot pattern is applied to the north pole portion of the permanent magnet 5. This is also true for other figures illustrating the polarity of the permanent magnet 5.

[0022] The plate-shaped metal member 6 is a member used to attach the permanent magnet 5 to the support member 7. In the illustrated example, the plate-shaped metal member 6 is joined to the support member 7 by welding. The plate-shaped metal member 6 also functions as a movable magnetic member and is configured to control the path of the magnetic field lines generated by the permanent magnet 5. The plate-shaped metal member 6 also constitutes the driving means DM. In this embodiment, the plate-shaped metal member 6 includes a central portion 6C to which the permanent magnet 5 is attached, a rear portion 6B disposed behind the central portion 6C, a front portion 6F disposed in front of the central portion 6C, a left portion 6L disposed to the left of the central portion 6C, and a right portion 6R disposed to the right of the central portion 6C. In the example shown in FIGS. 1 and 2 , the permanent magnet 5 is attracted to the ceiling surface CP of the plate-shaped metal member 6. The permanent magnet 5 and the plate-shaped metal member 6 may be fixed to each other with an adhesive. In this case, the plate-shaped metal member 6 may be made of a non-magnetic metal, and the driving means DM may be composed of a coil 4 and a permanent magnet 5 .

[0023] The driving means DM is an example of a vibration force generator and is configured to vibrate the movable body MB along the vibration axis VA. In this embodiment, the driving means DM is an electromagnetic driving mechanism and is composed of a base plate 2 (a fixed magnetic member), a coil 4 (a fixed magnetic field generating member), a permanent magnet 5 (a movable magnetic field generating member), and a plate-shaped metal member 6 (a movable magnetic member). Specifically, the driving means DM is configured to use a Lorentz force corresponding to the direction and magnitude of the current supplied to the coil 4 under the control of the control unit CTR to vibrate the movable body MB (the permanent magnet 5), which is elastically supported by the support member 7, along the vibration axis VA.

[0024] The support member 7 is disposed between the fixed body FB (housing HS) and the movable body MB and is configured to elastically support the movable body MB. In this embodiment, the support member 7 is a leaf spring formed of a metal plate and includes a left elastic support portion 7L attached to the inner surface (Y2 side) of the left plate portion 1A2 of the housing HS, a right elastic support portion 7R attached to the inner surface (Y1 side) of the right plate portion 1A4 of the housing HS, and a central portion 7C provided between the left elastic support portion 7L and the right elastic support portion 7R. In the illustrated example, the central portion 7C functions as a connecting plate portion connecting the left elastic support portion 7L and the right elastic support portion 7R. Note that the central portion 7C may be omitted. In this case, the left elastic support portion 7L and the right elastic support portion 7R are each separate and independent members that are separately fixed to the movable body MB.

[0025] The support member 7 may also include a reinforcing plate portion that suppresses deformation of the central portion 7C. Specifically, the reinforcing plate portion includes, for example, at least one of a front extending portion that extends downward from the front edge of the central portion 7C and a rear extending portion that extends downward from the rear edge of the central portion 7C.

[0026] The support member 7 will now be described in detail with reference to Figures 3, 4, and 5. Figure 3 is a six-view diagram of the support member 7. Figures 4 and 5 are diagrams of the support member 7 that supports the movable body MB (the permanent magnet 5 and the plate-shaped metal member 6) so that it can reciprocate. Specifically, Figure 4 is a perspective view of the permanent magnet 5, the plate-shaped metal member 6, and the support member 7, the upper view of Figure 5 is a front view of the permanent magnet 5, the plate-shaped metal member 6, and the support member 7, and the lower view of Figure 5 is a bottom view of the permanent magnet 5, the plate-shaped metal member 6, and the support member 7.

[0027] The central portion 7C is configured to be fixed to the upper surface of the plate-shaped metal member 6. In this embodiment, the lower surface of the central portion 7C is fixed to the upper surface of the plate-shaped metal member 6 by welding.

[0028] The left elastic support portion 7L elastically supports the movable body MB and includes a left standing portion 7L1, a first left deformation portion 7L2, a left folded portion 7L3, a second left deformation portion 7L4, and a left fixed portion 7L5. The left standing portion 7L1 connects the left end portion LE of the central portion 7C (see the top view of FIG. 3 ) to the first left deformation portion 7L2. In this embodiment, the left standing portion 7L1 is formed by bending the left end portion LE of the central portion 7C, which extends in the X-axis direction, as a fold line. The left standing portion 7L1 includes a portion that is linear in front view. In this embodiment, the left standing portion 7L1 is configured to extend downward (in the Z2 direction) perpendicular to the central portion 7C. The first left deformation portion 7L2 is a portion that is linear in top view. In this embodiment, the first left-side deformation portion 7L2 is configured to extend forward (in the X1 direction) from the left-side upright portion 7L1. The left-side folded portion 7L3 is configured to extend leftward (in the Y1 direction) from the front end of the first left-side deformation portion 7L2 and curve convexly forward. In this embodiment, the left-side folded portion 7L3 is configured to have a U-shape in top view so that stress acting on the left-side folded portion 7L3 is dispersed over a wide area. The second left-side deformation portion 7L4 is a linear portion extending rearward (in the X2 direction) from the left end of the left-side folded portion 7L3. The left-side fixing portion 7L5 is a portion fixed to the housing HS. In this embodiment, the left-side fixing portion 7L5 extends rearward (in the Z1 direction) from the rear end of the second left-side deformation portion 7L4 parallel to the left side plate portion 1A2 of the cover 1 and is fixed to the left side plate portion 1A2 by welding. However, the left-side fixing portion 7L5 may be fixed by welding or the like to another part of the housing HS, such as the front side plate portion 1A1, the rear side plate portion 1A3, the top plate portion 1B, or the base plate 2. The first left-side deforming portion 7L2, the left-side folded portion 7L3, and the second left-side deforming portion 7L4 are also referred to as the left-side deforming portion 7LT (see the top view in FIG. 3 ), which is a portion that deforms in response to the reciprocating movement of the movable body MB.

[0029] The right elastic support portion 7R elastically supports the movable body MB and includes a right standing portion 7R1, a first right deformation portion 7R2, a right folded portion 7R3, a second right deformation portion 7R4, and a right fixed portion 7R5. The right standing portion 7R1 connects the right end portion RE of the central portion 7C (see the top view of FIG. 3 ) to the first right deformation portion 7R2. In this embodiment, the right standing portion 7R1 is formed by bending the right end portion RE of the central portion 7C, which extends in the X-axis direction, as a fold line. The right standing portion 7R1 includes a portion that is linear in front view. In this embodiment, the right standing portion 7R1 is configured to extend downward (in the Z2 direction) perpendicular to the central portion 7C. The first right deformation portion 7R2 is a portion that is linear in top view. In this embodiment, the first right deforming portion 7R2 is configured to extend rearward (in the X2 direction) from the right standing portion 7R1. The right folded portion 7R3 is configured to extend rightward (in the Y2 direction) from the rear end of the first right deforming portion 7R2 and curve convexly rearward. In this embodiment, the right folded portion 7R3 is configured to have a U-shape in top view so that stress acting on the right folded portion 7R3 is dispersed over a wide area. The second right deforming portion 7R4 is a linear portion extending forward (in the X1 direction) from the right end of the right folded portion 7R3. The right fixing portion 7R5 is a portion fixed to the housing HS. In this embodiment, the right fixing portion 7R5 extends forward (in the X1 direction) from the front end of the second right deforming portion 7R4 parallel to the right side plate portion 1A4 of the cover 1 and is fixed to the right side plate portion 1A4 by welding. However, the right-side fixing portion 7R5 may be fixed by welding or the like to another part of the housing HS, such as the front side plate portion 1A1, the rear side plate portion 1A3, the top plate portion 1B, or the base plate 2. The first right-side deformation portion 7R2, the right-side folded portion 7R3, and the second right-side deformation portion 7R4 are also referred to as a right-side deformation portion 7RT (see the top view in FIG. 3 ), which is a portion that deforms in response to the reciprocating movement of the movable body MB.

[0030] The left side 6L of the plate-shaped metal member 6 is configured to restrict the leftward movement of the permanent magnet 5 (left side magnet 5L) attached to the plate-shaped metal member 6 fixed to the central portion 7C relative to the plate-shaped metal member 6. The right side 6R of the plate-shaped metal member 6 is configured to restrict the rightward movement of the permanent magnet 5 (right side magnet 5R) attached to the plate-shaped metal member 6 fixed to the central portion 7C relative to the plate-shaped metal member 6. The rear side 6B of the plate-shaped metal member 6 is configured to restrict the rearward movement of the permanent magnet 5 attached to the plate-shaped metal member 6 fixed to the central portion 7C relative to the plate-shaped metal member 6. The front side 6F of the plate-shaped metal member 6 is configured to restrict the forward movement of the permanent magnet 5 attached to the plate-shaped metal member 6 fixed to the central portion 7C relative to the plate-shaped metal member 6.

[0031] Specifically, the rear portion 6B has a central rear portion 6BC, a left rear portion 6BL, and a right rear portion 6BR, while the front portion 6F has a central front portion 6FC, a left front portion 6FL, and a right front portion 6FR. The left rear portion 6BL and the left front portion 6FL are configured to function as a left stopper that limits movement of the movable body MB to the left (Y1 direction), and the right rear portion 6BR and the right front portion 6FR are configured to function as a right stopper that limits movement of the movable body MB to the right (Y2 direction). Specifically, when the movable body MB moves a predetermined distance to the left, the left rear portion 6BL and the left front portion 6FL come into contact with the inner surface of the left side plate portion 1A2 of the tubular portion 1A, thereby preventing further leftward movement of the movable body MB. In addition, the right rear portion 6BR and the right front portion 6FR are configured to come into contact with the inner surface of the right side plate portion 1A4 of the tubular portion 1A when the movable body MB moves a predetermined distance to the right, thereby suppressing further movement of the movable body MB to the right.

[0032] Next, the reciprocating motion of the movable body MB caused by the driving means DM will be described with reference to Figures 6, 7, and 8. Figure 6 is a detailed view of the vibration generator 101. Specifically, the upper view of Figure 6 is a top view of the vibration generator 101, and the lower view of Figure 6 is a longitudinal cross-sectional view of the vibration generator 101 taken on an imaginary plane parallel to the YZ plane including the dashed-dotted line L1 in the upper view of Figure 6, as viewed from the X1 side. Specifically, the lower view of Figure 6 shows the vibration generator 101 in its initial state. The initial state of the vibration generator 101 refers to the state of the vibration generator 101 when no current is supplied to the coil 4.

[0033] Fig. 7 is a top view of the coil 4, the movable body MB (the permanent magnet 5 and the plate-shaped metal member 6), and the support member 7. Specifically, the upper view of Fig. 7 shows the state when the movable body MB has moved to the left (Y1 direction), the center view of Fig. 7 shows the state when the movable body MB is in a neutral position (not moving), and the lower view of Fig. 7 shows the state when the movable body MB has moved to the right (Y2 direction). Note that, for the sake of explanation, parts of the coil 4 and the support member 7 that are actually hidden by the movable body MB are shown with hidden lines (dashed lines) in Fig. 7.

[0034] Fig. 8 is a front view of the conductive plate-shaped member 3, the coil 4, the movable body MB (the permanent magnet 5 and the plate-shaped metal member 6), and the support member 7. Specifically, the upper view of Fig. 8 shows the state when the movable body MB has moved to the left (Y1 direction), the center view of Fig. 8 shows the state when the movable body MB is in a neutral position (not moving), and the lower view of Fig. 8 shows the state when the movable body MB has moved to the right (Y2 direction).

[0035] 6, the left-side magnet 5L constituting the permanent magnet 5 has its lower half magnetized to the north pole and its upper half magnetized to the south pole, while the right-side magnet 5R constituting the permanent magnet 5 has its lower half magnetized to the south pole and its upper half magnetized to the north pole.

[0036] When a current flows from the first end 4A (see FIG. 2) to the second end 4B (see FIG. 2) of the coil 4, the current flows counterclockwise in a top view, as indicated by the arrow AR1 in the upper diagram of FIG. 7. In this case, in the initial state, a current flows from the rear side (X2 side) to the front side (X1 side) in a top view in the wire bundle portion 4S (left wire bundle portion 4SL) of the coil 4 that faces the left magnet 5L in the up-down direction and extends linearly along the front-to-rear direction, and therefore a force that tries to move the left magnet 5L to the left (Y1 direction) acts on the left magnet 5L as a reaction force to the Lorentz force. Furthermore, in the initial state, a current flows from the front side (X1 side) to the rear side (X2 side) in top view through the bundled wire portion 4S (right side bundled wire portion 4SR), which faces the right side magnet 5R of the coil 4 in the vertical direction and extends linearly along the front-to-rear direction, and therefore a force acts as a reaction force to the Lorentz force, tending to move the right side magnet 5R to the left (Y1 direction).

[0037] As a result, the movable body MB is biased leftward (in the Y1 direction) as indicated by the block arrow AR3 in the lower view of FIG. 6 and moves leftward as indicated by the upper views of FIGS. 7 and 8. When the movable body MB moves leftward a predetermined distance, the left front side 6FL and the left rear side 6BL of the plate-shaped metal member 6 come into contact with the inner surface of the left plate portion 1A2 of the tubular portion 1A, restricting further leftward movement of the movable body MB. Note that for the sake of explanation, the position of the left plate portion 1A2 of the tubular portion 1A is indicated by a dashed line in FIGS. 7 and 8. Furthermore, the control unit CTR is typically configured to vibrate the movable body MB so that the left front side 6FL and the left rear side 6BL of the plate-shaped metal member 6 do not come into contact with the inner surface of the left plate portion 1A2 of the tubular portion 1A.

[0038] In this case, as shown in the upper diagram of Fig. 7, the left-hand elastic support member 7L is compressed so that the distance DL1 in the left-right direction (Y-axis direction) between the left end LE of the central portion 7C and the left fixing portion 7L5 becomes smaller than the distance DL0 in the initial state (see the center diagram of Fig. 7). Also, the right-hand elastic support member 7R is expanded so that the distance DR1 in the left-right direction (Y-axis direction) between the right end RE of the central portion 7C and the right fixing portion 7R5 becomes larger than the distance DR0 in the initial state.

[0039] Conversely, when current flows from the second end 4B (see FIG. 2) to the first end 4A (see FIG. 2) of the coil 4, the current flows clockwise in a top view, as indicated by the arrow AR2 in the lower diagram of FIG. 7. In this case, in the left-side wiring portion 4SL, which faces the left-side magnet 5L of the coil 4 in the vertical direction in the initial state, current flows from the front (X1 side) to the rear (X2 side) in a top view, so that a force acting as a reaction force to the Lorentz force acts on the left-side magnet 5L, tending to move the left-side magnet 5L to the right (Y2 direction). Also, in the right-side wiring portion 4SR, which faces the right-side magnet 5R of the coil 4 in the vertical direction in the initial state, current flows from the rear (X2 side) to the front (X1 side) in a top view, so that a force acting as a reaction force to the Lorentz force acts on the right-side magnet 5R.

[0040] As a result, the movable body MB is biased to the right (Y2 direction) and moves rightward as shown in the lower diagrams of FIGS. 7 and 8. When the movable body MB moves rightward a predetermined distance, the right front side portion 6FR and the right rear side portion 6BR of the plate-shaped metal member 6 come into contact with the inner surface of the right side plate portion 1A4 of the tubular portion 1A, restricting further rightward movement of the movable body MB. Note that for the sake of explanation, the position of the right side plate portion 1A4 of the tubular portion 1A is indicated by a dashed line in FIGS. 7 and 8. Furthermore, the control unit CTR is typically configured to vibrate the movable body MB so that the right front side portion 6FR and the right rear side portion 6BR of the plate-shaped metal member 6 do not come into contact with the inner surface of the right side plate portion 1A4 of the tubular portion 1A.

[0041] In this case, as shown in the lower diagram of Figure 7, the left-hand elastic support member 7L is expanded so that the distance DL2 in the left-right direction (Y-axis direction) between the left end LE of the central portion 7C and the left fixing portion 7L5 becomes larger than the distance DL0 in the initial state (see the center diagram of Figure 7). Also, the right-hand elastic support member 7R is compressed so that the distance DR2 in the left-right direction (Y-axis direction) between the right end RE of the central portion 7C and the right fixing portion 7R5 becomes smaller than the distance DR0 in the initial state.

[0042] The control unit CTR can, for example, repeatedly reverse the direction of the current flowing through the coil 4 at a period corresponding to the natural frequency of the support member 7, thereby alternately generating the state shown in the upper diagram of FIG. 7 and the state shown in the lower diagram of FIG. 7, sandwiched between the state shown in the center diagram of FIG.

[0043] Specifically, the control unit CTR stops the supply of current to the coil 4 when the vibration generator 101 reaches the state shown in the upper diagram of Fig. 7. When the supply of current to the coil 4 is stopped, the Lorentz force and its reaction force disappear. At this time, the movable body MB is pushed back to the right (Y2 direction) by the restoring force of the support member 7. The same is true when the vibration generator 101 reaches the state shown in the lower diagram of Fig. 7.

[0044] Alternatively, the control unit CTR may cause the movable body MB to reciprocate in the left-right direction by switching between supplying and stopping the current to the coil 4 without reversing the direction of the current flowing through the coil 4.

[0045] Next, the positional relationship between the conductive plate-shaped member 3, the movable body MB, and the support member 7 will be described with reference to Fig. 9. Fig. 9 is a top view of the conductive plate-shaped member 3, the movable body MB, and the support member 7. Specifically, the top view of Fig. 9 is a top view of the movable body MB (the permanent magnet 5 and the plate-shaped metal member 6), the center view of Fig. 9 is a top view of the movable body MB supported by the support member 7, and the bottom view of Fig. 9 is a top view of the conductive plate-shaped member 3, the movable body MB, and the support member 7 showing the positional relationship between the conductive plate-shaped member 3, the movable body MB, and the support member 7.

[0046] As shown in the upper diagram of Figure 9, a through hole 6H and a notch 6K are formed in the central portion 6C of the plate-shaped metal member 6, exposing a portion of the top surface of the permanent magnet 5. The notch 6K includes a left notch 6KL that exposes a portion of the top surface of the left magnet 5L and a right notch 6KR that exposes a portion of the top surface of the right magnet 5R. As shown in the center diagram of Figure 9, a through hole 7H and a notch 7K that exposes a portion of the top surface of the permanent magnet 5 are also formed in the central portion 7C of the support member 7. The notch 7K includes a left notch 6KL that exposes a portion of the top surface of the left magnet 5L and a right notch 6KR that exposes a portion of the top surface of the right magnet 5R. In the illustrated example, the position of the through hole 7H corresponds to the position of the through hole 6H, and the position of the notch 7K corresponds to the position of the notch 6K.

[0047] The through holes 6H and the notches 6K have the effect of making it easier for the magnetic flux generated by the permanent magnets 5 to reach the conductive plate-like member 3, compared to when the through holes 6H and the notches 6K are not formed in the central portion 6C of the plate-like metal member 6. The same applies to the through holes 7H and the notches 7K.

[0048] 9, the conductive plate-like member 3 does not have a through hole such as the through hole 6H in the plate-like metal member 6 or the through hole 7H in the support member 7, and does not have a notch such as the notch 6K in the plate-like metal member 6 or the notch 7K in the support member 7. Therefore, eddy currents flow more easily in the conductive plate-like member 3 than when an opening or notch is formed. Furthermore, because the conductive plate-like member 3 is entirely flat and does not have any recesses or protrusions, eddy currents flow more easily than when the conductive plate-like member 3 is not flat and has recesses or protrusions.

[0049] 9 , the conductive plate-like member 3 has a length LT2 that is shorter than the length LT1 of the permanent magnet 5 in the X-axis direction and a width W2 that is narrower than the width W1 of the permanent magnet 5 in the Y-axis direction. This is to prevent the magnetic flux from the permanent magnet 5 from penetrating through any portions of the conductive plate-like member 3. In the illustrated example, the width W2 of the conductive plate-like member 3 is set so that when the movable body MB (permanent magnet 5) moves a predetermined distance to the left (Y1 side) as shown in the upper diagram of FIG. 8 , the position of the right end 3RE of the conductive plate-like member 3 in the Y-axis direction is approximately the same as the position of the right end of the permanent magnet 5 (right-side magnet 5R), and so that when the movable body MB (permanent magnet 5) moves a predetermined distance to the right (Y2 side) as shown in the lower diagram of FIG. 8 , the position of the left end 3LE of the conductive plate-like member 3 in the Y-axis direction is approximately the same as the position of the left end of the permanent magnet 5 (left-side magnet 5L).

[0050] In the illustrated example, when the movable body MB vibrates along the vibration axis VA, the magnetic flux MF generated by the permanent magnet 5 included in the movable body MB also vibrates along the vibration axis VA. That is, the magnetic flux crossing the conductive plate-like member 3 above the permanent magnet 5 vibrates along the vibration axis VA while maintaining its relationship of crossing the conductive plate-like member 3. Therefore, eddy currents flow in the conductive plate-like member 3 to reduce changes in the density of the magnetic flux crossing the conductive plate-like member 3. The conductive plate-like member 3 is disposed so as to be perpendicular to the magnetic flux generated by the permanent magnet 5.

[0051] Therefore, the movable body MB is subjected to a braking force, which is a force caused by eddy currents and acts in the direction opposite to the direction of vibration (movement). Specifically, while the movable body MB is vibrated by the Lorentz force generated by the driving means DM, it is subjected to a braking force that acts to slow down the vibration. The braking force increases in proportion to the vibration velocity of the movable body MB. Therefore, the vibration acceleration at the natural frequency of the movable body MB and frequencies nearby is reduced by the braking force.

[0052] The braking force caused by eddy currents increases as the eddy currents increase. The eddy currents also increase as the resistivity (resistivity) of the conductive plate member 3 decreases, as the conductivity of the conductive plate member 3 increases, and as the thickness of the conductive plate member 3 increases. Therefore, the material and thickness of the conductive plate member 3 are selected so as to obtain a desired braking force. In the illustrated example, the conductive plate member 3 is made of tough-pitch copper, the same material as the wire material of the coil 4.

[0053] Furthermore, in a vibration generating device, the braking force due to eddy currents can be an undesirable force that reduces vibration acceleration, but the vibration generating device 101 according to one embodiment of the present disclosure is configured to suppress resonance of the movable body MB by actively utilizing the braking force due to eddy currents.

[0054] With this configuration, the vibration generator 101 can suppress resonance of the movable body MB by using a damping force caused by eddy currents flowing through the conductive plate member 3.

[0055] As described above, the electromagnetic vibration generator 101 according to an embodiment of the present disclosure includes a fixed body FB, a movable body MB, and a support member 7 that supports the movable body MB relative to the fixed body FB so that the movable body MB can vibrate in a first direction (Y-axis direction), as shown in FIG. 2 . The fixed body FB has a wire bundle 4S including a plurality of conductors extending in a second direction (X-axis direction) perpendicular to the first direction (Y-axis direction), and includes a coil 4 that is disposed on one side (Z2 side, lower side) of the movable body MB in a third direction (Z-axis direction) perpendicular to the first direction (Y-axis direction) and the second direction (X-axis direction). Furthermore, as shown in the lower diagram of FIG. 6 , the movable body MB includes a permanent magnet 5 that generates a first magnetic flux MF1 directed toward the wire bundle 4S side (Z2 side, lower side) and a second magnetic flux MF2 directed toward the opposite side (Z1 side, upper side) of the wire bundle 4S. Furthermore, as shown in the lower diagram of Figure 6, the fixed body FB is arranged on the other side (Z1 side, upper side) of the movable body MB in the third direction (Z-axis direction), extends along the first direction (Y-axis direction) so as to intersect with the second magnetic flux MF2, and includes a conductive plate-like member 3 in which eddy currents are generated when the movable body MB moves in the first direction (Y-axis direction).

[0056] With this configuration, the vibration generator 101 can suppress resonance of the movable body MB by using a damping force resulting from eddy currents flowing through the conductive plate member 3. Therefore, the vibration generator 101 can improve durability while achieving the effect of suppressing resonance, compared to a configuration that suppresses resonance using a gel damper member, sponge, or the like. In other words, this configuration has the effect of providing a vibration generator 101 having a highly durable structure that can suppress resonance of the movable body MB.

[0057] Furthermore, this configuration has the advantage of being able to increase the damping coefficient and achieve both high responsiveness and high peak acceleration compared to configurations that suppress resonance using a gel damper member, sponge, etc. Furthermore, this configuration has the advantage of being able to suppress distortion of the vibration waveform compared to configurations that suppress resonance using a gel damper member, sponge, etc. This is because in configurations that suppress resonance using a gel damper member, sponge, etc., the gel damper member or sponge affects the spring constant of the support member 7 (leaf spring), making it easy for the vibration waveform to be distorted.

[0058] Furthermore, compared to configurations that suppress resonance by providing a magnetic fluid layer in the gap between the coil and the permanent magnet, or the gap between the housing and the permanent magnet, the vibration generating device 101 has the advantage of being more stable against ambient temperature, i.e., its performance is less likely to change due to changes in ambient temperature.

[0059] Furthermore, compared to a configuration in which the conductive plate-like member 3 and the coil 4 are arranged on one side of the permanent magnet 5 (see the center and lower diagrams in FIG. 10 ), this configuration can reduce the distance between the conductive plate-like member 3 and the permanent magnet 5 and the coil 4. Therefore, compared to a configuration in which the conductive plate-like member 3 and the coil 4 are arranged on one side of the permanent magnet 5, this configuration has the effect of increasing the braking force caused by eddy currents caused by the interaction between the conductive plate-like member 3 and the permanent magnet 5 while suppressing a decrease in the driving force caused by the interaction between the coil 4 and the permanent magnet 5, i.e., while suppressing a decrease in the thrust constant.

[0060] 10 is a diagram illustrating the differences between the electromagnetic exciter 101 according to the embodiment of the present disclosure and the electromagnetic exciter 101X and electromagnetic exciter 101Y as comparative examples. Specifically, the upper diagram in Fig. 10 is a schematic cross-sectional view of the electromagnetic exciter 101, which corresponds to the lower diagram in Fig. 6. The center diagram in Fig. 10 is a schematic cross-sectional view of the electromagnetic exciter 101X, and the lower diagram in Fig. 10 is a schematic cross-sectional view of the electromagnetic exciter 101Y.

[0061] The vibration generator 101X differs from the vibration generator 101 in that it includes a plate-shaped metal member 6X that functions as a yoke plate instead of the plate-shaped metal member 6, and in that the conductive plate-shaped member 3 is disposed below the movable body MB and above the coil 4, but is otherwise the same as the vibration generator 101. Note that the plate-shaped metal member 6X functions as a yoke material and is therefore formed to be thicker than the plate-shaped metal member 6.

[0062] The vibration generator 101Y differs from the vibration generator 101 in that it includes a plate-shaped metal member 6X that functions as a yoke plate instead of the plate-shaped metal member 6, and in that the conductive plate-shaped member 3 is disposed below the movable body MB and below the coil 4, but is otherwise the same as the vibration generator 101. That is, the vibration generator 101Y differs from the vibration generator 101X in that the conductive plate-shaped member 3 is disposed below the coil 4, in that the conductive plate-shaped member 3 is disposed above the coil 4.

[0063] In the vibration generator 101X, the distance between the conductive plate member 3 and the permanent magnet 5 does not change compared to the vibration generator 101, but the distance between the coil 4 and the permanent magnet 5 becomes larger, resulting in a decrease in the driving force caused by the interaction between the coil 4 and the permanent magnet 5. On the other hand, in the vibration generator 101Y, the distance between the coil 4 and the permanent magnet 5 does not change compared to the vibration generator 101, but the distance between the conductive plate member 3 and the permanent magnet 5 becomes larger, resulting in a decrease in the braking force caused by the eddy current caused by the interaction between the conductive plate member 3 and the permanent magnet 5.

[0064] In contrast, in the vibration generator 101, the distance between the conductive plate member 3 and the permanent magnet 5 and the distance between the coil 4 and the permanent magnet 5 can be simultaneously reduced compared to the vibration generator 101X and the vibration generator 101Y. Therefore, the vibration generator 101 can increase the driving force caused by the interaction between the coil 4 and the permanent magnet 5 compared to the vibration generator 101X, and can increase the braking force caused by the eddy current caused by the interaction between the conductive plate member 3 and the permanent magnet 5 compared to the vibration generator 101Y.

[0065] 6 , the electromagnetic exciter 101 may include a plate-shaped metal member 6 that is attracted to the upper surface of the permanent magnet 5. That is, the plate-shaped metal member 6 may be made of a magnetic metal. In this case, the electromagnetic exciter 101 may be configured so that the second magnetic flux MF2 passes from the upper surface of the permanent magnet 5 through the plate-shaped metal member 6 toward the conductive plate-shaped member 3. For example, the plate-shaped metal member 6 may be made of a non-magnetic metal so as not to block the magnetic flux generated by the permanent magnet 5.

[0066] This configuration has the effect of easily attaching the permanent magnet 5 to the support member 7 via the plate-shaped metal member 6. This is because the permanent magnet 5 and the plate-shaped metal member 6 are joined to each other by magnetic force without the use of adhesive or the like. Furthermore, this configuration has the effect of preventing the plate-shaped metal member 6 from weakening the braking force caused by eddy currents resulting from the interaction between the conductive plate-shaped member 3 and the permanent magnet 5.

[0067] 9, the plate-shaped metal member 6 may have a through-hole 6H or a notch 6K that exposes the upper surface of the permanent magnet 5. In the illustrated example, the central portion 6C of the plate-shaped metal member 6 is formed with a circular through-hole 6H that exposes the upper surface of the central portion of the permanent magnet 5, a left-side notch 6KL that exposes the upper surface of the central portion of the left end of the left-side magnet 5L, and a right-side notch 6KR that exposes the upper surface of the central portion of the right end of the right-side magnet 5R.

[0068] Compared to a configuration in which no through hole 6H or notch 6K is formed in the central portion 6C of the plate-shaped metal member 6, this configuration makes it easier for the magnetic flux generated by the permanent magnet 5 to reach the conductive plate-shaped member 3, thereby having the effect of increasing the braking force caused by the eddy currents resulting from the interaction between the conductive plate-shaped member 3 and the permanent magnet 5.

[0069] The conductive plate member 3 may also be a component separate from the fixed body FB. In other words, the conductive plate member 3 may not be a part of the cover 1 or the base plate 2 that constitute the housing HS, but may be a component separate and independent from each of the cover 1 and the base plate 2.

[0070] This configuration has the advantage that even if the housing HS is made of a non-conductive material, the damping force caused by eddy currents can be used to suppress resonance of the movable body MB.

[0071] The conductive plate-like member 3 may also be made of a non-magnetic metal. This configuration can prevent a magnetic force (attraction force) from acting between the conductive plate-like member 3 and the permanent magnet 5, as occurs when the conductive plate-like member 3 is made of a magnetic metal, and has the effect of suppressing the efficient use of the driving force by the driving means DM from being hindered by such an attraction force.

[0072] Furthermore, the conductive plate member 3 may be formed of a material having a higher conductivity than the fixed body FB. For example, the conductive plate member 3 may be formed of a material having a higher conductivity than iron or an iron alloy. This configuration has the effect of increasing the damping force (force that suppresses vibration) caused by eddy currents. This is because the greater the conductivity, the greater the damping force caused by eddy currents. Therefore, this configuration has the effect of suppressing resonance of a heavier movable body MB, for example.

[0073] The conductive plate member 3 may also be formed to contain copper or aluminum. For example, the conductive plate member 3 may be formed of copper, aluminum, or an alloy thereof. This configuration has the effect of reducing material costs compared to when the conductive plate member 3 is formed of a precious metal such as silver or an alloy thereof.

[0074] The preferred embodiments of the present disclosure have been described above in detail. However, the present invention is not limited to the above-described embodiments. Various modifications or substitutions may be applied to the above-described embodiments without departing from the scope of the present invention. Furthermore, the features described with reference to the above-described embodiments may be combined as appropriate unless technically inconsistent.

[0075] This application claims priority based on Japanese Patent Application No. 2023-139211, filed on August 29, 2023, the entire contents of which are incorporated herein by reference.

[0076] DESCRIPTION OF SYMBOLS 1: Cover 1A: Cylindrical portion 1A1: Front plate portion 1A2: Left plate portion 1A3: Rear plate portion 1A4: Right plate portion 1B: Top plate portion 2: Base plate 3: Conductive plate-like member 3LE: Left end portion 3RE: Right end portion 4: Coil 4A: First end portion 4B: Second end portion 4S: Wire binding portion 4SL: Left wire binding portion 4SR: Right wire binding portion 5: Permanent magnet 5L: Left magnet 5R: Right magnet 6, 6X: Plate-like metal member 6B: Rear portion 6BC: Central rear portion 6BL: Left rear portion 6BR: Right rear portion 6C: Central portion 6F: Front portion 6FC: Central front portion 6FL: Left front portion 6FR: Right front portion 6H: Through hole 6K: Notch 6KL: Left notch 6KR...Right side cutout 6L...Left side portion 6R...Right side portion 7...Support member 7C...Central portion 7H...Through hole 7K...Notch 7KL...Left side cutout 7KR...Right side cutout 7L...Left side elastic support portion 7L1...Left side standing portion 7L2...First left side deformation portion 7L3...Left side folded portion 7L4...Second left side deformation portion 7L5...Left side fixed portion 7LT...Left side deformation portion 7R...Right side elastic support portion 7R1...Right side standing portion 7R2...First right side deformation portion 7R3...Right side folded portion 7R4...Second right side deformation portion 7R5...Right side fixed portion 7RT...Right side deformation portion 101, 101X, 101Y...Vibration generator BM...Insulating substrate CP...Ceiling surface CTR...Control portion DM...Drive means FB...Fixed body HS...Housing IT: Input terminal LE: Left end MB: Movable body PD1: First conductor pad PD2: Second conductor pad RE: Right end VA: Vibration axis VE: Vibration device

Claims

1. A vibration generating device comprising: a fixed body; a movable body; and a support member that supports the movable body relative to the fixed body so that the movable body can vibrate along a first direction, wherein the fixed body has a wire bundle section including a plurality of conductors extending in a second direction perpendicular to the first direction, and includes a coil arranged on one side of the movable body in a third direction perpendicular to the first and second directions, the movable body includes a permanent magnet that generates a first magnetic flux oriented toward the wire bundle section and a second magnetic flux oriented toward the opposite side of the wire bundle section, and the fixed body is arranged on the other side of the movable body in the third direction, and includes a conductive plate-like member that extends along the first direction so as to intersect with the second magnetic flux, and in which eddy currents are generated when the movable body moves in the first direction.

2. The vibration generating device according to claim 1, further comprising a plate-shaped metal member that is attracted to an upper surface of the permanent magnet, and the second magnetic flux passes from the upper surface of the permanent magnet through the plate-shaped metal member toward the conductive plate-shaped member.

3. The vibration generating device according to claim 2, wherein the plate-shaped metal member has a through hole or a notch that exposes the upper surface of the permanent magnet.

4. The vibration generating device according to claim 1, wherein the conductive plate member is a separate part from the fixed body.

5. The vibration generating device according to claim 4, wherein the conductive plate member is formed from a material having a higher electrical conductivity than the fixed body.

6. The vibration generating device according to claim 5, wherein the conductive plate member is formed containing copper or aluminum.

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