Patent Publication Number: US-2019184424-A1

Title: Vibration generating device

Description:
TECHNICAL FIELD 
     The present invention relates to a vibration generating device that generates various kinds of vibrations. 
     BACKGROUND ART 
     As an actuator that causes a user to perceive vibrations, a configuration has been proposed in which a magnetic drive mechanism having cylindrical coils and cylindrical magnets around a movable element is provided to vibrate the movable element in an axial direction (Patent Reference 1, 2). 
     CITATION LIST 
     Patent Literature 
     Patent reference 1: Japanese Unexamined Patent Application Publication 2002-78310 
     Patent reference 2: Japanese Unexamined Patent Application Publication 2006-7161 
     SUMMARY 
     Technical Problems 
     In the configurations disclosed in Patent Reference 1 and 2, however, sufficient vibration cannot be output when a relatively heavy vibration member is vibrated. 
     In consideration of the problem mentioned above, an object of the present invention is to provide a vibration generating device capable of sufficiently vibrating a relatively heavy vibration member. 
     Solutions to Problems 
     In order to solve the problem mentioned above, a vibration generating device of the present invention comprises a vibration member, multiple actuators connected to the vibration member, and a stationary element which supports the vibration member via the multiple actuators. Each of the multiple actuators includes: a supporting body to which the vibration member is fixed, a movable element, a first elastic member which has at least one of elasticity and viscoelasticity and is connected to the supporting body and the movable element, and a magnetic drive circuit which is configured to move the movable element linearly back and forth with respect to the supporting body. 
     In the present invention, when the movable element is linearly moved back and forth by the magnetic drive circuit, the position of the center of gravity of the actuator shifts and then vibration is output. Also, in this embodiment, the supporting bodies used in the multiple actuators are fixed to a common vibration member; therefore, vibrations generated by the multiple actuators are transmitted to the common vibration member. Therefore, even when the vibration member is relatively heavy, it can be vibrated with large amplitude. Since vibrations generated by the multiple actuators are transmitted to the common vibration member, different vibrations can be caused among the multiple actuators so that the common vibration member outputs various kinds of vibrations. 
     The present invention may adopt a configuration in which each of the multiple actuators has, as the magnetic drive circuit, a first magnetic drive circuit, which moves the movable element linearly back and forth with respect to the supporting body in a first direction, and a second magnetic drive circuit, which moves the movable element linearly back and forth with respect to the supporting body in a second direction crossing the first direction. According to this configuration, by causing different vibrations among the multiple actuators, the common vibration member can output various kinds of vibrations. 
     The present invention may adopt a configuration in which the vibration member is a plate member which extends in the first direction and in the second direction. According to this configuration, the vibration generating device can be made thinner. Also, even when the area of the vibration member is widened to increase the number of actuators which can be connected to the vibration member, vibrations with large amplitude can be output since the mass of the vibration member is small. 
     The present invention may adopt a configuration in which at least three actuators of the multiple actuators are arranged to appear to be around a center position of the vibration member when viewed from a third direction, which perpendicularly intersects with the first direction and the second direction. According to this configuration, vibrations generated by the multiple actuators can be efficiently transmitted to the common vibration member; also, by causing different vibrations among the multiple actuators, the common vibration member can generate various kinds of vibrations. 
     The present invention may adopt a configuration in which the multiple actuators are arranged point symmetric about the center position of the vibration member, or the multiple actuators are arranged line symmetric with respect to an imaginary line passing the center position. According to this configuration, vibrations generated by the multiple actuators can be efficiently output from the common vibration member; also, by causing different vibrations among the multiple actuators, the common vibration member can output various kinds of vibrations. 
     The present invention may adopt a configuration in which the multiple actuators generate vibrations in different directions. For example, some actuators among the multiple actuators, which are opposed to each other about the center position, generate vibrations which have opposite directionalities around the center position. According to this configuration, the common vibration member can output vibrations with either directionality around the center position. 
     The present invention may adopt a configuration in which the multiple actuators are supported to the stationary element via a second elastic member which are provided with at least one of elasticity and viscoelasticity. According to this configuration, the vibrations output from the multiple actuators are prevented from causing the actuators to resonate. 
     Effects of Invention 
     In this embodiment, when the movable element is moved linearly back and forth by the magnetic drive circuit in each of the multiple actuators, the center of gravity of each actuator shifts and then vibrations are output. Also, since the supporting bodies used in the multiple actuators are fixed to the common vibration member, vibrations generated by the multiple actuators are transmitted to the common vibration member. Therefore, even if the vibration member is relatively heavy, vibrations with large amplitude can be generated. Also, vibrations generated by the multiple actuators are transmitted to the common vibration member; therefore, if the multiple actuators are caused to generate different vibrations from each other, the common vibration member can output various kinds of vibrations. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  are explanatory diagrams of a vibration generating device to which the present invention is applied. 
         FIG. 2  is a perspective view of an actuator used in the vibration generating device to which the present invention is applied. 
         FIG. 3  are cross-sectional views of the actuator shown in  FIG. 2 . 
         FIG. 4  is a perspective exploded view of the actuator shown in  FIG. 2 . 
         FIG. 5  is a perspective exploded view of a major part of the actuator shown in  FIG. 2 . 
         FIG. 6  is a perspective exploded view of the major part of the actuator shown in  FIG. 2 , in which some of magnets and coils are removed from a movable element and a supporting body. 
         FIG. 7  is an explanatory diagram of an example of another layout of the actuator in the vibration generating device to which the present invention is applied. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Referring to the drawings, an embodiment of the present invention is described. Note that, for the purpose of clarifying the layout of a vibration generating device  100  and actuators  1  in the description below, the directions crossing each other are given as an X-axis direction, an Y-axis direction and a Z-axis direction; X 1  is given to one side in the X-axis direction, X 2  is given to the other side in the X-axis direction, Y 1  is given to one side in the Y-axis direction, Y 2  is given to other side in the Y-axis direction, Z 1  is given to one side in the Z-axis direction and Z 2  is given to the other side in the Z-axis direction. In the vibration generating device  100  or the actuators  1 , a drive force is generated by a magnetic drive circuit in either a first direction L 1  or a second direction L 2 . Here, the first direction L 1  extends along the X-axis direction; the second direction L 2  extends along the Y-axis direction; a third direction L 3  crossing the first direction L 1  and the second direction L 2  extends along the Z-axis direction. 
     (Configuration of Vibration Generating Device  100 ) 
       FIG. 1  shows explanatory diagrams of the vibration generating device  100  to which the present invention is applied:  FIGS. 1 ( a ) and ( b )  are respectively a plan view of the vibration generating device  100  and a cross-sectional view of the vibration generating device  100 . Note that, in  FIG. 1 ( a ) , the illustration of a top part of a stationary element is omitted so the internal configuration of the vibration generating device  100  can be easily understood. In  FIG. 1 ( a ) , also, fat arrows indicate directions of vibrations generated by each of the actuators; in  FIG. 2 , arrows L 1  and L 2  indicate the directions of vibrations caused by the magnetic drive circuits (a first magnetic drive circuit  10  and a second magnetic drive circuit  20 ) in each actuator  1 . 
     In  FIG. 1 , the vibration generating device  100  to which the present invention is applied comprises a vibration member  110 , multiple actuators  1  connected to the vibration member  110 , and a stationary element  150  for supporting the vibration member  110  via the multiple actuators  1 . The stationary element  150  is a casing which stores the vibration member  110  and the multiple actuators  1  therein; an opening portion  152  is created in an end plate  151  positioned on the other side Z 2  in the Z-axis direction so that the vibration member  110  is exposed to the other side Z 2  in the Z-axis direction. 
     Each of the multiple actuators  1  is provided with a supporting body  5  to which the vibration body  110  is fixed, a movable element  4 , a first elastic member  7  having at least elasticity or viscoelasticity, and magnetic drive circuits (a first magnetic drive circuit  10  and a second magnetic drive circuit  20 ) which cause the movable element  4  to move linearly back and forth with respect to the supporting body  5 ; the first elastic member  7  is connected to the supporting body  5  and the movable element  4 . The first elastic member  7  is, for example, a viscoelastic body such as a gel-based damper member which is described later. 
     Between each of the multiple actuators  1  and a bottom portion  153  of the stationary element  150 , a second elastic member  160  having at least elasticity or viscoelasticity is arranged; the stationary element  150  supports each of the multiple actuators  1  via the second elastic member  160 . The second elastic member  160  is a viscoelastic body such as a gel-based damper member, which is described later, in the same manner as the first elastic member  7 . 
     In each of the multiple actuators  1 , the first magnetic drive circuit  10  causes the movable element  4  to move linearly back and forth in the first direction L 1  along the X-axis direction with respect to the supporting body  5 ; the second magnetic drive circuit  20  causes the movable element  4  to move linearly back and forth in the second direction L 2  along the Y-axis direction with respect to the supporting body  5 . 
     The vibration member  110  is a plate member which extends in the first direction L 1  (the X-axis direction) and the second direction L 2  (the Y-axis direction); the multiple actuators  1  are respectively connected to the surface of the vibration member  110  on the other side Z 2  in the Z-axis direction. In this embodiment, the multiple actuators  1  are arranged such that at least three of them are placed around the center position O 110  of the vibration member  110 . 
     The planar shape of the vibration member  110  is a quadrangle. More specifically, the planar shape of the vibration member  110  is a rectangle and each of four actuators  1  is arranged around the center of each of four sides of the vibration member  110 . Therefore, the multiple actuators appear point symmetric about the center position O 110  of the vibration member  110  when viewed from the third direction L 3 . Also, the multiple actuators are arranged line symmetric with respect to a first imaginary line L 10 , which passes through the center position O 110  of the vibration member  110  and extends in the first direction L 1  (the X-axis direction), and also line symmetric with respect to a second imaginary line L 20 , which passes through the center position O 110  of the vibration member  110  and extends in the second direction L 2  (the Y-axis direction). 
     (Operation at Vibration Generating Device) 
     In the vibration generating device  100  configured as above, when the movable element  4  is vibrated in each of the multiple actuators  1 , vibrations are transmitted from each of the movable bodies  4  to the vibration member  110 . As a result of this, information is sent through vibrations to a user who is holding the vibration generating device  100 . For example, the vibration generating device  100  is built in a cell phone, etc. to notify the user of incoming calls/emails. The vibration generating device  100  can also be used for an operation member for a game machine, providing new sensation through vibrations. 
     More specifically described, when the movable element  4  in every actuator  1  is vibrated in the first direction L 1 , the vibration member  110  will be vibrated in the first direction L 1 ; therefore, the vibrations in the first direction L 1  are output from the vibration generating device  100 . On the other hand, when the movable element  4  in every actuator  1  is vibrated in the second direction L 2 , the vibration member  110  will be vibrated in the second direction L 2 ; therefore, the vibrations in the second direction L 2  are output from the vibration generating device  100 . At that time, if the speed of the movable element  4  moving back and forth is differentiated on one side from the other side, vibrations having directionality can be generated in the actuator  1 . Therefore, actuators among the multiple actuators  1 , which are opposed to each other about the center position O 110 , may generate vibrations having opposite directionalities from each other around the center position O 110 . Even more specifically described, two actuators  1  which are opposed in the second direction L 2  may generate vibrations having opposite directionalities from each other in the first direction L 1  while two other actuators  1  which are opposed in the first direction L 1  may generate vibrations having opposite directionalities from each other in the second direction L 2 ; it may be set so that the directionalities of the vibrations generated by the four actuators  1  move in one way in the circumferential direction. In this case, the vibration member  110  generates vibrations having a directionality in one way around the center position O 110 . Therefore, vibrations having a directionality in one way around the center position O 110  are output from the vibration generating device  100 . 
     (Overall Configuration of Actuator  1 ) 
       FIG. 2  is a perspective view of the actuator  1  used in the vibration generating device  100  to which the present invention is applied.  FIG. 3  shows cross-sectional views of the actuator  1  shown in  FIG. 2 ;  FIGS. 3 ( a ) and ( b )  are respectively an XZ cross-sectional view taken along a line passing through the center portion of the actuator  1  and a YZ cross-sectional view taken along a line passing the center portion of the actuator  1 .  FIG. 4  is an exploded perspective view of the actuator  1  shown in  FIG. 2 . 
     In  FIG. 2 ,  FIG. 3  and  FIG. 4 , the first magnetic drive circuit  10  in an actuator  1  has first coils  12  held to the supporting body  5  and first magnets  11  held to the movable element  4 ; the first magnets  11  and the first coils  12  are opposed to each other in the Z-axis direction (the third direction L 3 ). The second magnetic drive circuit  20  has second coils  22  held to the supporting body  5  and second magnets  21  held to the movable element  4 ; the second magnets  21  and the second coils  22  are opposed to each other in the Z-axis direction (the third direction L 3 ). The first magnetic drive circuit  10  generates a drive force in the first direction L 1  which is the X-axis direction; the second magnetic drive circuit  20  generates a drive force in the second direction L 2  which is the Y-axis direction. Here, the first magnets  11  and the first coils  12  are arranged at two places which are opposed in the first direction L 1 . Likewise, the second magnets  21  and the second coils  22  are arranged at two places which are opposed in the second direction L 2 . In other words, the second magnetic drive circuit  20  is arranged at two places which are opposed in the second direction L 2 . 
     (Configuration of Supporting Body  5 ) 
       FIG. 5  is a perspective view of an exploded major part of the actuator  1  shown in  FIG. 2 .  FIG. 6  is a perspective view of the exploded major part of the actuator  1  shown in  FIG. 2 , in which some of the magnets and coils are removed from the movable element  4  and the supporting body  5 . 
     The supporting body  5  has a first casing  56  positioned on one side Z 1  in the X-axis direction, a second casing  57  covering the first casing  56  from the other side Z 2  in the Z-axis direction, and a holder  58  (a holder in the supporting body) arranged between the first casing  56  and the second casing  57 ; the first casing  56  and the second casing  57  are fixed together by four fixing screws, interposing the holder  58  between them. 
     The second casing  57  has an end plate portion  571  having a square planar shape when viewed in the Z-axis direction and four side plate portions  572 , each of which protrudes from the edge of each end plate portion  571 . In the end plate portion  571 , a circular hole  576  is created in the center and a fixing hole  575  is created at four corners. In the center portion of each of the four side plate portions  572 , a notch portion  573  is formed by cutting from one side Z 1  to the other side Z 2  in the X-axis direction. In the side plate  572  on the other side X 2  in the Z-direction, a notch portion  574  is created by cutting the portion next to the notch portion  573  by a partial height in the Z-direction. 
     The first casing  56  is provided with an end plate portion  561  having a square planar shape when viewed from the Z-axis direction and a boss portion  562  protruding from each of the four corners of the end plate portion  561  toward the end plate portion  571  of the second casing  57 . In the center of the end plate portion  561 , a circular hole  566  is created. The boss portion  562  is provided with a step surface  563  formed part of the way in the Z-axis direction and a cylindrical portion  564  protruded from the step surface  563  toward the other side Z 2  in the Z-axis direction. Therefore, by screwing the fixing screws  59  to the bosses  562  of the first casing  56  through the fixing holes  575  of the second casing  57  from the other side Z 2  in the Z-axis direction, the end plate portion  571  of the first casing  56  is fixed to the edge on one side Z 1  in the Z-axis direction of the side plate portions  572 . The first casing  56  is provided with a rising portion  565  which is to be opposed to the notch portion  574  of the second casing  57  in the first direction L 1 ; the rising portion  565  configures with the notch portion  574  a slit which is used to position a base board  26 . Connected to the base board  26  are a feeder [to supply power] to the first coils  12  and the second coils  22 . 
     As shown in  FIG. 3 ,  FIG. 5  and  FIG. 6 , two holders  58  are layered in the Z-axis direction between the first casing  56  and the second casing  57 . The basic configurations of the two holders  58  are shared, and a hole  583  is formed in the center of each holder  58 . In this embodiment, the hole  583  is circular. Circular holes  581  are formed at four corners of each of the two holders  58 ; the cylindrical portions  564  of the bosses  562  are inserted in the circular holes  581  and the holders  58  are positioned and held at the step surfaces  563 . In the center of each of the four sides of the holder  58 , a recess portion  582  is indented toward the inner circumference. 
     Plate members of the same configuration are inverted in the Z-axis direction to configure the two holders  58 . Therefore, column-like protrusions  585  protrude from the holder  58 , which is arranged on the one side Z 1  in the Z-axis direction, toward the first casing  56  while multiple column-like protrusions  585  protrude from the other holder  58 , arranged on the other side Z 2  in the Z-axis direction, toward the second casing  57 . Also, a spherical contact portion  586  is formed at a tip end of each of the multiple column-like protrusions  585 . Therefore, as the first casing  56  and the second casing  57  are fixed by the fixing screw  59  interposing the holders  58  between them, the positioning of the first casing  56 , the two holders  58  and the second casing  57  in the Z-axis direction is determined with certainty. 
     (Arrangement of First Coil  12  and Second Coil  22 ) 
     In each of the two holders  58 , an elongated through hole  589  is formed at four places between the recess portions  582  and the hole  583 . In each of the two holders  58 , a first coil  12  of the first magnetic drive circuit  10  are held inside the two through holes  589  which are opposed in the first direction L 1 . Also, in each of the two holders  58 , a second coil  22  of the second magnetic drive circuit  20  is held inside the two through holes  589  which are opposed in the second direction L 2 . Therefore, each of the two holders  58  holds the first coils and the second coils  22  in one layer in the Z-axis direction, and the first coils  12  and the second coils  22  are respectively layered in the Z-axis direction in the supporting body  5 . The first coil  12  is a flat coreless coil having a long side, which is an effective side, in the Y-axis direction; the second coil  22  is also a flat coreless coil having a long side, which is its effective side, in the X-axis direction. 
     (Configuration of Movable Element  4 ) 
     The movable element  4  has a sheet-like first holder  41  (a holder for a movable element) which is positioned on one side Z 1  in the Z-axis direction of the two holders  58 , a sheet-like second holder  42  (a holder for a movable element) which is positioned on the other side Z 2  in the Z-axis direction of the two holders  58 , and a sheet-like third holder  43  (a holder for a movable element) which is positioned between the two holders  58 . The first holder  41 , the second holder  42  and the third holder  43  respectively have four protrusion portions  45  which protrude to both sides in the X-axis direction and in the Y-axis direction to appear as in a +(plus) shape when viewed in the Z-axis direction. The tip end portion of each protrusion portion  45  formed to the first holder  41  is formed as a joint part  44  which is bent to the other side Z 2  in the Z-axis direction, and the tip end portion of each protrusion portion  45  formed to the second holder  42  is formed as a joint part  44  which is bent to one side Z 1  in the Z-axis direction. Therefore, when the first holder  41 , the second holder  42  and the third holder are assembled together in layers, the tip end portion of each protrusion portion  45  of the first holder  41  contacts the tip end portion of the corresponding protrusion portion  45  of the second holder  42  and the third holder  43 . By joining the corresponding tip end portions of the protrusion portions  45  of the first holder  41 , the second holder  42  and the third holder  43  by a method of adhesive or welding, the first holder  41 , the second holder  42  and the third holder  43  are joined together. 
     (Arrangement of First Magnet  11  and Second Magnet  21 ) 
     The first holder  41 , the second holder  42  and the third holder  43  respectively each have a rectangular through hole  419 ,  429  and  439  formed in each of the four protrusion portions  45  which protrude to both sides in the X-axis direction and in the Y-axis direction. First magnets  11  of the first magnetic drive circuit  10  are held in the through holes  419 ,  429  and  439  of the two protrusion portions  45  which are opposed in the X-axis direction. Also, second magnets  21  of the second magnetic drive circuit  20  are held in the through holes  419 ,  429  and  439  in the two protrusion portions  45  which are opposed in the Y-axis direction. Therefore, the first holder  41 , the second holder  42  and the third holder  43  respectively hold the first magnets  11  and the second magnets  21  in one layer in the Z-axis direction. 
     As described, the multiple first coils  12  are arranged in layers in the Z-axis direction, and the first magnets  11  are arranged at both sides in the Z-axis direction of each of the first coils  12  of the first magnetic drive circuit  10 . Also, the multiple second coils  22  are arranged in layers in the Z-axis direction and the second magnets  21  are arranged at both sides in the Z-axis direction of each of the multiple second coils  22  of the second magnetic drive circuit  20 . In this embodiment, the first coils  12  and the second coils  22  are arranged in two layers in the Z-axis direction, and the first magnets and the second magnets  21  are arranged at both sides in the Z-axis direction of each of the multiple first coils and the second coils  22  in each layer. The first magnet  11  is a sheet magnet, of which the magnetizing and polarizing line extends in the Y-axis direction; the second magnet  21  is also a sheet magnet, of which the magnetizing and polarizing line extends in the X-axis direction. 
     A back yoke  8  is layered on one side Z 1  in the Z-axis direction of each of the first magnets  11  and the second magnets  21  held in the first holder  41 . Also, a back yoke  8  is layered on the other side Z 2  in the Z-axis direction of each of the first magnets  11  and the second magnets  21  held in the second holder  42 . The back yoke  8  is larger than the first magnet  11  or the second magnet  21  (the size of the through hole  419 ,  429 ) in size and fixed to the first holder  41  or the second holder  42  by a method of adhesive, etc. 
     (Configuration of Elastic Member  7 ) 
     Between the back yoke  8  provided to the first holder  41  and the end plate portion  561  of the first casing  56 , an elastic member  7  which contacts the back yoke  8  and the first casing  56  is provided at four positions [where the yokes are]. Between the back yoke  8  provided to the second holder  42  and the end plate portion  571  of the second casing  57 , an elastic member  7  which contacts the back yoke  8  and the second casing  57  is provided at four positions [where the yokes are]. 
     In this embodiment, the elastic member  7 , a viscoelastic body, is composed of a gel-based damper member  70  and is arranged between the movable element  4  and the supporting body  5 . In this embodiment, the gel-based damper member  70  is a silicone gel sheet. The planar shape of the elastic member  7  is in a polygon such as a rectangle; the portion of the end plate portion  561  of the first cover  56  and the portion of the end plate portion  571  of the second cover  57  in which the elastic members  7  are positioned are made as recess portions  569  and  579  ( FIG. 3 ). Viscoelasticity has characteristics of both viscosity and elasticity, which are remarkably found in a polymer substance such as a gel-based member, a plastic, a rubber, etc. Therefore, various kinds of gel-based members can be adopted for the elastic member  7  (the viscoelastic body). Also, the gel-based damper member  70  (the viscoelastic body) may use various rubber materials and their modified materials such as natural rubber, diene-based rubber (such as styrene butadiene rubber, isoprene rubber or butadiene rubber), chloroprene rubber, acrylonitrile butadiene rubber, etc.) non-diene-based rubber (such as butyl rubber, ethylene propylene rubber, ethylene propylene diene rubber, urethane rubber, silicone rubber, fluororubber, etc.) or thermoplastic elastomer, etc. 
     The gel-based damper member  70  has viscoelasticity and has linear or nonlinear stretch characteristics according to its stretch direction. For example, a sheet gel-based damper member  70  demonstrates the stretch characteristics in which a nonlinear component (a spring constant) is larger than a linear component (a spring constant) when pressed and compressively deformed in its thickness direction (the axial direction). On the other hand, when pulled and stretched in the thickness direction (the axial direction), it demonstrates the stretch characteristics in which a linear component (a spring constant) is larger than a nonlinear component (a spring constant). Because of this, when the sheet gel-based damper member  70  is pressed and compressively deformed in the thickness direction (in the axial direction) between the movable element  4  and the supporting body  5 , it is prevented from being significantly deformed; therefore, the gap between the movable element  4  and the supporting body  5  is prevented from changing significantly. On the other hand, when the sheet gel-based damper member  70  is deformed in the direction (the sheering direction) crossing the thickness direction (the axial direction), the deformation is in the direction the elastic member  7  is pulled and stretched no matter which direction it moves; therefore, it demonstrates the deformation characteristics in which a linear component (a spring constant) is larger than a nonlinear component (a spring constant). Therefore, a spring force by a moving direction is constant in the sheet-like gel-based damper member  70  (the viscoelastic body). Therefore, by using the spring element in the sheering direction of the sheet-like gel-based damper member  70  (the viscoelastic body), the reproducibility of vibratory acceleration to the input signals can be improved, enabling it to produce vibrations with delicate nuance. In this embodiment, the gel-based damper member  70  is composed of a column-like (sheet-like) silicone gel with penetration of 10° to 110°. In this embodiment, the gel-based damper member  70  is composed of a quadrangular prism-shaped (sheet-like) silicone gel. It is composed of a silicone-based gel with penetration of 10° to 110°. Penetration is defined by JIS-K-2227 or JIS-K-2220, where the smaller the value is the harder the material is. Note that, in this embodiment, the second elastic member  160  which is described referring to  FIG. 1  is also a gel-based damper member  70  in the same manner as the first elastic member  7 . 
     (Configuration of Stopper Mechanism  50 ) 
     As shown in  FIG. 3 , etc., in the center of the first holder  41 , a protruded coupling portion  411  having a smaller outside diameter than the hole  583  in the holder  58  protrudes to the other side Z 2  in the Z-axis direction; in the center of the second holder  42 , a protruded coupling portion  421  having a smaller outside diameter than the hole  583  in the holder  58  protrudes to one side Z 1  in the Z-axis direction. In the center of the third holder  43 , a protruded coupling portion  431  having a smaller outside diameter than the hole  583  of the holder  58  protrudes to one side Z 1  in the Z-axis direction and a protruded joint portion  432  having a smaller outside diameter than the hole  583  in the holder  58  protrudes to the other side Z 2  in the Z-axis direction. The protruded coupling portion  431  in the third holder  43  is in contact with the protruded coupling portion  411  of the first holder  41  inside the hole  583  of the holder  58 . The protruded joint portion  432  in the third holder  43  is in contact with the protruded coupling portion  421  of the second holder  42  inside the hole  583  of the holder  58 . At the tip end portions of the protruded coupling portions in the third holder  43 , positioning protrusion portions  433  and  434  are respectively formed; at the tip end portions of the protruded coupling portions  411  and  421 , recess portions  413  and  423  are respectively formed for the protruded portions  433  and  434  to fit into. Also, the protruded coupling portion  431  in the third holder  43  is coupled with the protruded coupling portion  411  in the first holder  41  by an adhesive, etc.; the protruded coupling portion  432  in the third holder  43  is coupled with the protruded coupling portion  421  in the second holder  42  by an adhesive, etc. Therefore, the first holder  41 , the second holder  42  and the third holder  43  are connected to each other at a body portion, which consists of the protruded coupling portions  411 ,  431 ,  432  and  421 , inside the hole  583  of the holder  58 . 
     Consequently, a wall portion  584  on the inside of the hole  583  of the holder  58  which is provided to the supporting body  5  surrounds the circumferential surface of the body portion  40  provided to the movable element  4  to configure a stopper mechanism  50  which restricts the movable range of the movable element  4  in the direction perpendicular to the Z-axis direction. 
     (Operation at Actuator  1 ) 
     In the actuator  1  of this embodiment, the first coils  12  of the first magnetic drive circuit  10  are electrified with alternating current to vibrate the movable element  4  in the third direction L 1  which is the X-axis direction. The second coils  22  of the second magnetic drive circuit  20  are electrified with alternating current to vibrate the movable element  4  in the second direction L 2  which is the Y-axis direction. At that time, the center of gravity in the actuator  1  shifts in the first direction L 1  and in the second direction L 2 ; therefore, the vibration member  110 , which is described referring to  FIG. 1 , vibrates in the first direction L 1  and in the second direction L 2 . Therefore, a user can perceive the vibrations in the first direction L 1  and the vibrations in the second direction L 2 . Also, if the alternate current waveform applied to the first coils  12  is adjusted to differentiate the speed at which the movable element  4  moves toward one side in the first direction L 1  from the speed at which the movable element  4  moves toward the other side in the first direction, a user can perceive vibrations having a directionality in the first direction L 1 . In the same manner, if the alternate current waveform applied to the second coils  22  is adjusted to differentiate the speed of the movable element  4  moving toward one side in the second direction L 2  from its speed moving toward the other side in the second direction L 2 , a user can perceive vibrations having a directionality in the second direction L 2 . 
     In the first magnetic drive circuit  10  and the second magnetic drive circuit  20 , the first coils  12  and the first magnets  11  are opposed to each other in the Z-axis direction (the third direction L 3 ), and the second coils  22  and the second magnets  21  are opposed to each other in the Z-axis direction (the third direction L 3 ). Therefore, even when both the first magnetic drive circuit  10  and the second magnetic drive circuit  20  are provided, the dimension of the actuator  1  in the Z-axis direction can be kept relatively small. For this reason, in the first magnetic drive circuit  10  and the second magnetic drive circuit  20 , the first coils  12  and the second coils  22  are arranged in two layers in the Z-axis direction and the first magnets  11  and the second magnets  21  are arranged at both sides in the Z-axis direction of each of the first coils  12  and the second coils  22  in each layer to increase the strength of the first magnet drive circuit  10  and the second magnet drive circuit  20 ; even in this case, the dimension of the actuator  1  in the Z-axis direction can be kept relatively small. Since the first magnets  11  and the second magnets  21  are arranged at both sides in the third direction L 3  of each of the first coils  12  and the second coils  22  in each layer, there is less magnetic flux leakage, compared to the case in which the magnet is opposed to only one surface of the coil. Therefore, the thrust to move the movable element  4  can be increased. 
     The first magnetic drive circuits  10  are provided at two places in each layer which are opposed in the X-axis direction and the circuits  10  in two layers are aligned with each other when viewed in the Z-axis direction. Also, the second magnetic drive circuits  20  are provided at two places in each layer which are opposed in the Y-axis direction and the circuits  20  in two layers are aligned with each other when viewed in the Z-axis direction. For this reason, when the first magnetic drive circuits  10  and the second magnetic drive circuits  20  are driven to vibrate the movable element  4  in the first direction L 1  and the second direction L 2 , the movable element  4  is not easily rotated around the axial direction extending in the Z-axis direction; therefore, the movable element  4  can efficiently be vibrated. 
     Also, in this embodiment, a stopper mechanism  50  which restricts the movable range of the movable element  4  in the direction orthogonally intersecting with the Z-axis direction is provided, utilizing [the space] between the first magnetic drive circuits  10  which are opposed to each other in the first direction L 1  and [the space] between the second magnetic drive circuits  20  which are opposed to each other in the second direction L 2 . When the movable element  4  vibrates in the first direction L 1  and in the second direction L 2 , the first elastic member  7  (the gel-based damper member  70 ) deforms in the sheering direction; however, because of [the function of the stopper mechanism  50 ], the movable range of the movable element  4  can be less than the maximum deformation amount in the sheering direction of the gel-based damper member  70 . Therefore, even if the movable element  4  vibrates at maximum, the gel-based damper member  70  won&#39;t stretch more than the maximum deformation amount; therefore, damage to the gel-based damper member  70  can be avoided. Also, the stopper mechanism  50  is provided utilizing the space between the first magnetic drive circuits  10 , which are opposed to each other in the first direction L 1 , and the space between the second magnetic drive circuits  20 , which are opposed to each other in the second direction L 2 ; therefore, even when the stopper mechanism  50  is present, the actuator  1  can be kept from becoming larger. 
     When a spring member is used for the first elastic member  7  which is connected to the movable element  4  and the supporting body  5  in the actuator  1 , the movable element  4  may sometimes resonate at the frequency which corresponds to the mass of the movable element  4  and the spring constant of the spring member; however, in this embodiment, the gel-based damper member  70  is used for the first elastic member  7 . Also, in this embodiment, only the gel-based member  70  is used for the first elastic member  7 , and the gel-based damper member  70  has deformation characteristics of no spring component or little spring component depending on the deforming direction. For this reason, the movable element  4  is restricted from resonating. Also, the gel-based damper member  70  is fixed to both the movable element  4  and the supporting body  5  by a method of adhesive. Therefore, the gel-based damper member  70  is prevented from moving following the movement of the movable element  4 . Accordingly, the gel-based damper member  70  can be solely used for the first elastic member  7 ; therefore, the configuration of the actuator  1  can be simplified. Also, the gel-based damper member  70  has a penetration from 90° to 110°. For this reason, the gel-based damper member  70  has an elasticity sufficient to demonstrate the damper function, and also will not easily be broken into pieces and scattered. 
     The gel-based damper member  70  deforms in the direction (the sheering direction) perpendicularly intersecting with the thickness direction (the axial direction) as the movable element  4  moves in the first direction L 1  and the second direction L 2 . Therefore, in the actuator  1 , when the movable element  4  is vibrated in the first direction L 1  and in the second direction L 2 , the deformation characteristics in the sheering direction of the gel-based damper member  70  is used. In the deformation characteristics in the sheering direction of the gel-based damper member  70  here has more linear components than non-linear components. Therefore, in the driving direction (the first direction L 1  and the second direction L 2 ) of the actuator  1 , the vibration characteristics of good linearity can be obtained. 
     Major Effects of This Embodiment 
     As described above, in the vibration generating device  100  of this embodiment, when the movable element  4  is moved linearly back and forth by the magnetic drive circuit in each of the multiple actuators  1 , the center of gravity of the actuator  1  is shifted and the vibrations are output. In this embodiment, the supporting bodies  5  used in the multiple actuators  1  are fixed to the common vibration member  110 ; therefore, vibrations generated in the multiple actuators  1  are transmitted to the common vibration member  110 . Therefore, even when the vibration member  110  is relatively heavy, it can be vibrated with large amplitude. Further, since vibrations generated in the multiple actuators  1  are transmitted to the common vibration member  110 , the movable bodies  4  in some of the multiple actuators  1  may be linearly moved back and forth in the direction different from that of the other actuators  1  so that different vibrations can be generated among the multiple actuators  1 , and therefore, the common vibration member  110  can output various kinds of vibrations. 
     Each of the multiple actuators  1  has the first magnetic drive circuit  10  which vibrates the movable element  4  in the first direction L 1  and the second magnetic drive circuit  20  which vibrates the movable element  4  in the second direction L 2 . For this reason, by causing different vibrations among the multiple actuators  1 , the common vibration member  110  can output various kinds of vibrations. 
     The vibration member  110  is a plate member which extends in the first direction L 1  and in the second direction L 2 ; therefore, the vibration generating device  100  can be made thinner. Also, even when the area of the vibration member  110  is widened to increase the number of the actuators  1  which can be connected to the vibration member  110 , the mass of the vibration member  110  is still small and therefore vibrations with large amplitude can be output. 
     Since at least three actuators of the multiple actuators are arranged to appear to be around the center position O 110  of the vibration member  110  when viewed in the third direction L 3  (in the Z-axis direction), vibrations generated in those multiple actuators  1  can be efficiently transmitted to the common vibration member  110 ; by causing different vibrations among the multiple actuators  1 , the common vibration member  110  can output various kinds of vibrations. 
     Also, the multiple actuators  1  are arranged point symmetric about the center position O 110  of the vibration member  110  and also arranged line symmetric with respect to a first imaginary line L 10  and a second imaginary line L 20  which pass through the center position O 110  as center. For this reason, vibrations generated in the multiple actuators  1  can be efficiently transmitted to the common vibration member  110 ; by causing different vibrations among the multiple actuators  1 , the common vibration member  110  can output various kinds of vibrations. 
     (Example of Another Layout of Actuators  1 ) 
       FIG. 7  is an explanatory diagram of another layout example of actuators  1  in the vibration generating device  100  to which the present invention is applied. 
     In the above-described embodiment, four actuators  1  are arranged near the centers of four sides of the vibration member  110 ; however, in this embodiment, as shown in  FIG. 7 , four actuators  1  are arranged at four corners of the vibration member  110 . For this reason, the multiple actuators  1  are arranged point symmetric about the center position O 110  of the vibration member  110 . Also, the multiple actuators are arranged line symmetric with respect to the first imaginary line L 10  which passes through the center position O 110  of the vibration member  110  and extends in the first direction L 1  (the X-axis direction) and also line symmetric with respect to the second imaginary line L 20  which passes through the center position O 110  of the vibration member  110  and extends in the second direction L 2  (the Y-axis direction). 
     Another Embodiment 
     In the above-described embodiment, only the gel-based damper member is used for the first elastic member  7  and the second elastic member  160 ; however, a spring may be used or a spring and a gel-based damper member may be used in combination for the first elastic member  7  and the second elastic member  160 . 
     DESCRIPTION OF REFERENCE NUMERALS 
     
         
         
           
               1  Actuator 
               4  Movable element 
               5  Supporting body 
               7  First elastic member 
               8  Back yoke 
               10  First magnetic drive circuit 
               110  Vibration member 
               11  First magnet 
               12  First coil 
               20  Second magnetic drive circuit 
               21  Second magnet 
               22  Second coil 
               50  Stopper mechanism 
               56  First casing 
               57  Second casing 
               58  Holder 
               70  Gel-based damper member 
               100  Vibration generating device 
               150  Stationary element 
               160  Second elastic member 
             L 1  First direction 
             L 2  Second direction 
             L 10  First imaginary line 
             L 20  Second imaginary line 
             O 110  Center position