JP5975185B2 - Tactile presentation device - Google Patents

Description

  The present invention relates to a haptic presentation device that provides haptic feedback by transmitting vibration to a user.

  In recent years, a touch-sensitive keyboard or the like has been proposed that provides tactile feedback by transmitting vibrations when a user touches a key to feel the key “pressed”.

  For example, Patent Document 1 describes a structure in which both ends of a piezoelectric bimorph element made of piezoelectric ceramics or the like are held by a low elastic body, and a vibrating material is connected to the center of the piezoelectric bimorph. In the structure of Patent Document 1, vibration is transmitted to a user through a connected vibration-receiving material by inputting an AC signal to the piezoelectric bimorph element and causing it to vibrate.

JP 2005-303937 A

  However, there is a problem that piezoelectric ceramics are easily broken. On the other hand, a material that is difficult to break, such as a piezoelectric film, has a weak force to transmit vibration and is difficult to use for a tactile sense presentation device.

  Therefore, an object of the present invention is to provide a tactile sense presentation device that can transmit a strong vibration to some extent even when a film is used.

  A tactile sensation presentation apparatus according to the present invention includes a film that deforms in a plane direction when a voltage is applied thereto, a flat diaphragm that is fixed to the film in a state where bending stress is generated, and a touch detection unit that detects a touch operation. A drive unit that applies a drive signal to the film when the touch detection unit detects a touch operation. And the film is arrange | positioned at the both main surfaces of the diaphragm.

  In such a tactile sense presentation device, when the user performs a touch operation, a drive signal is applied to the film, and the film expands and contracts. The diaphragm vibrates in a direction perpendicular to the main surface due to expansion and contraction of the film. Since the bending stress is generated in the diaphragm, it can be vibrated efficiently with respect to the expansion and contraction of the film. Moreover, the film is arrange | positioned at both the main surfaces of a diaphragm. Therefore, the amount of expansion and contraction of the piezoelectric film is increased as compared with the mode in which the piezoelectric film is disposed only on one main surface. Therefore, the tactile sense presentation device of the present invention can transmit a strong vibration to some extent even when a film is used.

  The “film” may be composed only of a piezoelectric film made of a piezoelectric resin, or may be an aspect composed of a piezoelectric film and a flat exciter film having the piezoelectric film mounted on the main surface. May be. In addition, the “film that deforms in the plane direction when a voltage is applied” is not limited to a piezoelectric film. Examples of the “film that deforms in the plane direction when a voltage is applied” include an electrostrictive film, an electret film, a composite film, and an electroactive film. An electroactive film is a film member that generates stress by electrical driving, or a film member that deforms and generates displacement by electrical driving. Specifically, there are an electrostrictive film, a composite material (a material obtained by resin-molding piezoelectric ceramics), an electrically driven elastomer, or a liquid crystal elastomer.

  In addition, it is preferable that the edge part of a diaphragm becomes a curved surface shape without an angle | corner. In this case, the film at the end of the diaphragm expands and contracts smoothly without being caught at the corners at the end of the diaphragm, so that loss of expansion and contraction can be suppressed.

  In addition, the aspect which detects the touch operation with respect to a diaphragm may be sufficient as a touch detection part, and the aspect which detects the touch with respect to the touchscreen with which a diaphragm is mounted | worn may be sufficient.

  In addition, the diaphragm may be in a mode in which bending stress is generated by being fixed to the film while being curved in a direction orthogonal to the main surface of the film, or in a state where the diaphragm is not fixed to the film, the flat plate surface is It may be a curved shape, and may be a mode in which bending stress is generated by being fixed to the film so that the curved flat plate surface is flat.

  Moreover, the film is not limited to a single film, and may be divided into a plurality of films.

  When the film is made of a piezoelectric film provided with a piezoelectric resin, the piezoelectric resin can be made of polyvinylidene fluoride or a chiral polymer. In the case where the chiral polymer is polylactic acid, a tactile sensation presentation device having a high translucency in almost the entire surface when viewed from the front can be realized by using a material having translucency along with other components.

  According to the present invention, strong vibration can be transmitted to some extent even when a film is used, and generation of sound can be suppressed even when the film is attached to a flat plate.

1 is an external perspective view of a tactile presentation device 10. FIG. It is the rear view and side view of the tactile sense presentation device 10. 1 is an external perspective view of a tactile presentation device 10. FIG. 2 is a partially enlarged side view of the tactile sense presentation device 10. FIG. 1 is a block diagram illustrating a configuration of a tactile sense presentation device 10. FIG. 10 is an operation explanatory diagram of the tactile presentation device 10. It is a side view of 10 A of tactile sense presentation apparatuses. It is an external appearance perspective view of the tactile sense presentation device 10B. It is structure explanatory drawing of the tactile sense presentation apparatus 10B. It is sectional drawing of the piezoelectric film which concerns on a modification.

  FIG. 1 is an external perspective view of a tactile presentation device 10 according to the first embodiment. 2A is a rear view of the tactile sense presentation device 10, and FIG. 2B is a side view.

  The tactile sense presentation device 10 includes a piezoelectric film 20A, a piezoelectric film 20B, an exciter film 30A, an exciter film 30B, a diaphragm 40, and a touch panel 50. The tactile sense presentation device 10 is a so-called keyboard, and a flat touch panel 50 is provided with a plurality of touch sensors 80 at positions corresponding to the key arrangement. The touch sensor 80 corresponds to the touch detection unit of the present invention. The touch sensor 80 may be of any type as long as it has a function of detecting a user's touch operation, and various types such as a membrane type, a capacitance type, and a piezoelectric film type may be used.

  The touch panel 50 is attached to one main surface (front surface) of the flat diaphragm 40. The diaphragm 40 has a rectangular shape in plan view. Diaphragm 40 is in contact with exciter film 30 </ b> A and exciter film 30 </ b> B at both ends in the lateral direction on the other main surface (back surface) and part of the front surface.

  The diaphragm 40 is made of, for example, acrylic resin PMMA. The diaphragm 40 may be made of other materials such as a metal plate, PET, polycarbonate (PC), PLLA, and glass.

  Note that the touch panel 50 is not essential. For example, a plurality of touch sensors 80 may be provided on the front surface of the diaphragm 40 at positions corresponding to the key arrangement. The touch panel 50 itself may be a diaphragm. In this case, since it is not necessary to prepare a diaphragm separately, the whole apparatus can be made thin.

  The exciter film 30A is attached to the right end portion when the diaphragm 40 is viewed from the front. The exciter film 30B is attached to the left end portion when the diaphragm 40 is viewed from the front. Since the exciter film 30A and the exciter film 30B have the same material and the same shape and the same function, the exciter film 30A will be mainly described in the following description.

  The exciter film 30A is a rectangular member that is thin and long in one direction. The exciter film 30A is made of, for example, polyethylene terephthalate (PET). The exciter film 30A may use other materials such as polyethylene nanophthalate (PEN), polyethylene (PE), polypropylene (PP), and polyvinyl chloride (PVC). Moreover, the same material as the piezoelectric film 20A and the piezoelectric film 20B may be used. The thickness of the exciter film 30A is desirably a thickness that does not hinder stretchability (for example, about 0.02 to 0.5 mm).

  The exciter film 30 </ b> A is attached to the front surface of the vibration plate 40 so as to go from the back surface side of the vibration plate 40 to the front surface side of the vibration plate 40 through both ends of the vibration plate 40 in the short direction. In this example, both ends of the exciter film 30A in the longitudinal direction are separated from each other. However, as shown in FIG. 3, both ends in the longitudinal direction of the exciter film 30A are in contact with each other, and the exciter film 30A is mounted at the center position of the diaphragm 40. Also good. Moreover, it is preferable that the place where the exciter film 30A is mounted is a place (node point) where the displacement of the deflection of the diaphragm 40 is small. By mounting at the node point, it is less affected by changes in the resonance frequency due to changes with time of various materials. Further, the number of times the exciter film 30A wraps around the diaphragm 40 is not once, but may be a mode in which the exciter film 30A is mounted after it wraps around more than once. Further, the number of exciter films is not limited to this example. For example, only one exciter film may be mounted in the center, or three or more may be mounted.

  Next, FIG. 4 is a partially enlarged side view of the portion where the piezoelectric film 20 </ b> A is mounted in the tactile sense presentation device 10. Since the piezoelectric film 20A and the piezoelectric film 20B have the same material and the same shape and have the same function, the piezoelectric film 20A will be mainly described in the following description. As shown in FIG. 4, the piezoelectric film 20 </ b> A is thin and has a base film 200 that is a rectangular member that is long in one direction, and electrodes 201 </ b> A and 201 </ b> B formed on both opposing main surfaces of the base film 200. Is provided.

  The base film 200 is a piezoelectric resin, and for example, a material such as polyvinylidene fluoride (PVDF) or a chiral polymer is used. More preferably, polylactic acid (PLA) having high translucency is used. In particular, it is desirable to be made of PLLA. In the case of using PLA, the tactile sensation presentation device 10 having a high translucency in almost the entire front view can be realized by using a material having a high translucency in other configurations. Further, PLA is not pyroelectric and is not affected by changes in ambient temperature. Therefore, the intensity of vibration does not change due to changes in temperature, heat generation of electronic equipment, temperature changes caused by contact with a finger, and the like. Moreover, since PLA has high translucency, it is not necessary to hide the portion where the PLA is attached when the tactile presentation device is viewed from the front. As a result, the apparatus can be miniaturized. Moreover, since the edge part of a film does not overlap with the edge part of a diaphragm, the structure of this invention does not need to provide the location which affixes a film on the edge part of a diaphragm. Therefore, it is effective for downsizing the apparatus.

  When the base film 200 is composed of PLLA, as shown in FIG. 2 (A), by cutting each outer periphery to be approximately 45 ° with respect to the stretching direction, a rectangular shape is formed, Give piezoelectricity.

  The electrode 201 </ b> A and the electrode 201 </ b> B are formed on substantially the entire main surfaces of the base film 200. The electrode 201A and the electrode 201B are preferably composed mainly of indium tin oxide (ITO), zinc oxide (ZnO), and polythiophene. In addition, it is also possible to use a silver nanowire electrode for the electrode 201A and the electrode 201B, and it is preferable to use an aluminum vapor-deposited electrode as long as the light transmitting property may be low. A lead wiring conductor (not shown) is connected to the electrode 201A and the electrode 201B, and a drive signal is applied to the electrode 201A and the electrode 201B through the wiring conductor. The electrode 201A disposed on the side of the exciter film 30A is attached to the exciter film 30A via the adhesive layer 60.

  As a result, the piezoelectric film 20A is attached to the exciter film 30A and, like the exciter film 30A, wraps around the front surface of the diaphragm 40 via both ends of the diaphragm 40 in the short direction, and the front surface of the diaphragm 40 Also arranged on the side. However, the piezoelectric film 20A does not have to be attached to the entire main surface of the exciter film 30A. Moreover, the aspect by which a piezoelectric film is divided | segmented into plurality and several piezoelectric films are mounted | worn with respect to one exciter film may be sufficient. When providing a plurality of piezoelectric films, the same click feeling can be obtained regardless of which button on the touch panel is pressed by applying different voltages to each of the piezoelectric films. In addition, by making the piezoelectric film into pieces, it is difficult to generate wrinkles or bubbles when pasted on the exciter film. As a result, the force of the piezoelectric film can be transmitted to the maximum.

  FIG. 5 is a block diagram illustrating the configuration of the tactile sense presentation device 10. As shown in FIG. 5, when the user touches the touch sensor 80 provided on the touch panel 50, the drive unit 81 applies a drive signal to the electrodes of the piezoelectric film 20A (and the piezoelectric film 20B). As a result, the piezoelectric film 20A (and the piezoelectric film 20B) expands and contracts.

  As shown in FIG. 1 and FIG. 2B, the diaphragm 40 is fixed to the exciter film 30A so as to have a shape that curves and protrudes toward the front side. With this configuration, a hollow region 100 is formed between the diaphragm 40 and the exciter film 30A.

  However, in the present embodiment, the curved state of the diaphragm 40 is exaggerated for the sake of explanation. Actually, the main surface of the diaphragm 40 and the main surface of the exciter film 30A are closer to parallel. The hollow region 100 is desirably as small as possible.

  Thus, since the vibration plate 40 is fixed to the exciter film 30A with the flat plate surface being curved, the bending film is applied to the exciter film 30A as indicated by the white arrow F901 in FIG. 2B. Fixed. Further, the exciter film 30A has an end portion in the short-side direction of the diaphragm 40 from the central portion on the main surface, as indicated by a white arrow S901 in FIG. It will be in the state pulled by. In a portion arranged in front of the diaphragm 40, as shown by a white arrow S902 in FIG. 2B, from the end in the short direction of the diaphragm 40, a fixed portion (exciter film) with the diaphragm 40 is provided. It will be in the state pulled by the end of 30A in the longitudinal direction).

  FIG. 6 is an explanatory diagram of the operation of the tactile sense presentation device 10, and FIG. 6 (A) shows a state at a timing when the piezoelectric film 20A is contracted by the drive signal. FIG. 6B shows a state where no drive signal is applied or the amplitude of the drive signal is zero. FIG. 6C shows a state at the timing when the piezoelectric film 20A is extended by the drive signal.

  When the drive unit 81 applies a drive signal to the piezoelectric film 20A and applies an electric field in the first direction of the piezoelectric film 20A, as shown in FIG. 6A, the piezoelectric film 20A has the diaphragm 40 on the back side. It contracts toward the center from the end portion in the short direction, and contracts toward the end portion in the short direction of the diaphragm 40 on the front side.

  In the exciter film 30A, the back side of the exciter film 30A contracts in the central direction on the back surface of the diaphragm 40 as the piezoelectric film 20A contracts as indicated by the arrow S911 in FIG. At this time, the exciter film 30A is slightly curved toward the front side in the direction orthogonal to the main surface. In addition, the exciter film 30A has a front side of the vibration plate 40, the side of the exciter film 30A attached to the vibration plate 40 is in the end direction in accordance with the contraction of the piezoelectric film 20A indicated by an arrow S915 in FIG. Shrink to.

  Accordingly, the diaphragm 40 is pulled in the central direction from the end portion in the short direction. Thereby, the diaphragm 40 is curved so as to protrude further forward as indicated by an arrow F911 in FIG. Since the exciter film 30A and the piezoelectric film 20A are disposed on both main surfaces of the diaphragm, the piezoelectric film 20A has an increased amount of contraction and is more strongly pulled than the diaphragm 40 when disposed only on the back side. it can.

  On the other hand, when the drive unit 81 applies a drive signal to the piezoelectric film 20A and applies an electric field in the second direction opposite to the first direction, as shown in FIG. On the side, it extends from the center of the diaphragm 40 toward the end in the short direction, and on the front side that wraps around, it extends toward the center.

  In the exciter film 30A, the back side of the exciter film 30A extends in the end direction on the back surface of the vibration plate 40 with the expansion of the piezoelectric film 20A indicated by an arrow S912 in FIG. At this time, the exciter film 30A is slightly curved toward the back side in the direction orthogonal to the main surface. Further, the exciter film 30A is stretched in the center direction in the front of the diaphragm 40 as the piezoelectric film 20A is stretched as indicated by an arrow S917 in FIG.

  Therefore, the diaphragm 40 is pulled from the central direction to the end portion in the short direction. Thereby, the diaphragm 40 is in a curved state in which the amount of forward protrusion is reduced, as indicated by an arrow F912 in FIG. Since the exciter film 30A and the piezoelectric film 20A are disposed on both main surfaces of the diaphragm, the piezoelectric film 20A has an increased amount of expansion and is more strongly pulled than the diaphragm 40 when disposed only on the back side. it can.

  Therefore, the diaphragm 40 changes to the state shown in FIG. 6A or the state shown in FIG. 6C based on the state shown in FIG. 6B according to the amplitude of the drive signal. It vibrates along the direction (direction orthogonal to the main surface of the diaphragm 40). Thereby, the vibration according to the drive signal is transmitted to the touch panel 50 via the diaphragm 40 and transmitted to the user who touched the touch panel 50. Therefore, when the user touches the touch sensor 80 of the touch panel 50, the vibration is fed back, so that the user can feel that the key is “pressed”.

  Since a stationary bending stress is applied to the diaphragm 40 in a non-operating state, the force applied to the diaphragm 40 when the piezoelectric film 20A and the exciter film 30A are extended has the same direction as the bending stress. Become. Therefore, the tactile sense presentation device 10 can vibrate the diaphragm 40 efficiently and can transmit a strong vibration to some extent even when a piezoelectric film is used. In addition, the tactile sense presentation device 10 can be made thinner than vibration caused by a motor or the like.

  In particular, the exciter film 30 </ b> A and the piezoelectric film 20 </ b> A of the present embodiment are disposed on both main surfaces of the diaphragm 40. For this reason, the piezoelectric film 20A has a larger amount of expansion than the piezoelectric film 20A disposed only on the back surface side, can pull the diaphragm 40 more strongly, and can generate strong vibration.

  The hollow region 100 may be filled with a soft resin such as silicone gel to the extent that the movement of the diaphragm is not hindered. As a result, it is possible to suppress the sound generated when the exciter film 30A and the diaphragm 40 vibrate.

  Next, a tactile sense presentation device according to a second embodiment will be described. FIG. 7 is a side view of the tactile sense presentation device 10A according to the second embodiment. The tactile sense presentation device 10A is different from the vibration plate 40 of the tactile sense presentation device 10 in that the end in the short direction of the vibration plate 40A has a curved shape with no corners. The exciter film 30A and the piezoelectric film 20A wrap around from the back side to the front side along the roundness of the end in the short direction of the vibration plate 40A, and are mounted on the front surface of the vibration plate 40A. Other configurations and functions are the same as those of the tactile sense presentation device 10.

  In this case, the exciter film 30 </ b> A and the piezoelectric film 20 </ b> A at the end portion in the short direction extend and contract smoothly without being caught at the corners at the end portion of the vibration plate, and thus it is possible to suppress a loss in expansion and contraction.

  Next, a tactile sense presentation device according to a third embodiment will be described. FIG. 8 is an external perspective view of a tactile presentation device 10A according to the third embodiment. FIG. 9A shows a state before the diaphragm 40B is fixed, and FIG. 9B is a structural explanatory view showing a state in which the diaphragm 40B is in contact with the exciter film 30A. ) Is a view showing a state where the exciter film 30 </ b> A and the piezoelectric film 20 </ b> A are wound around the front and attached.

  The tactile presentation device 10B according to the third embodiment is different from the tactile presentation device 10 according to the first embodiment in that the diaphragm 40B is not curved. Other configurations are the same as those of the tactile sense presentation device 10.

  The diaphragm 40B is made of the same material as the diaphragm 40 shown in the first embodiment, but as shown in FIG. 9A, in a state where the diaphragm 40B is not fixed to the exciter film 30A (and the exciter film 30B), The flat plate surface is curved. Such a shape can be realized, for example, by bending a diaphragm having a flat main surface by heat treatment or the like.

  As shown in a hollow arrow St902 in FIG. 9A, the vibration plate 40B applies a bending force to both ends, and as shown in FIG. 9B, the frame 70 has a flat curved surface. To the exciter film 30A. As shown in FIG. 9C, the exciter film 30A is attached to the front surface of the diaphragm 40B by going around the front surface of the diaphragm 40B via both ends of the diaphragm 40B in the short direction.

  When the diaphragm 40B is fixed to the exciter film 30A in such a state, a bending stress is generated as in the first embodiment. 9C, the exciter film 30A is pulled from the center position of the main surface toward both ends of the diaphragm 40 and the position of the frame 70 on the back side of the diaphragm 40. . Further, on the front side of the diaphragm 40, the diaphragm 40 is pulled from both ends of the diaphragm 40 and the position of the frame 70 toward the mounting position with the diaphragm 40 (end portion of the exciter film 30 </ b> A).

  Even with such a configuration, the same operational effects as those of the first embodiment described above can be obtained. Furthermore, if the configuration of the present embodiment is used, the main surface of the diaphragm 40B can be fixed flat. Therefore, the touch panel 50B attached to the diaphragm 40B can also be made flat.

  Next, FIG. 10A is a side view of a piezoelectric film 90A according to a modification of the piezoelectric film 20A. The piezoelectric film 20A illustrated in FIG. 4 has a structure in which one base film 200 is sandwiched between the electrode 201A and the electrode 201B. However, the piezoelectric film 90A illustrated in FIG. 10A includes the base film 200, the electrode 201A, and the electrode 201B. A plurality of layers are stacked. In this example, electrodes 201 </ b> A and electrodes 201 </ b> B are alternately arranged with each base film 200 interposed therebetween. Thus, by laminating the plurality of base films 200, the electrodes 201A, and the electrodes 201B, the stretchability is further improved, and strong vibration can be generated.

  On the other hand, FIG. 10B is a side view of the piezoelectric film 90B according to the second modification. The piezoelectric film 90B shown in FIG. 10B realizes a laminated structure by sandwiching one base film 200 between the electrode 201A and the electrode 201B and bending and stacking the base film 200, the electrode 201A, and the electrode 201B. It is. Also in this case, the stretchability is further improved, and a strong vibration can be generated. However, in this case, it is preferable to reinforce the electrical connection by applying a conductive paste or the like at a portion where the electrode is bent.

  In the present invention, the “exciter film” is not an essential component, and a piezoelectric film may be directly attached to the diaphragm. When the piezoelectric film is directly attached, the movement of the piezoelectric film can be efficiently transmitted to the diaphragm because the exciter film is not interposed.

  In the present invention, the “film that deforms in the plane direction when a voltage is applied” is not limited to a piezoelectric film. Examples of the “film that deforms in the plane direction when a voltage is applied” include an electrostrictive film, an electret film, a composite film, and an electroactive film.

  An electroactive film is a film member that generates stress by electrical driving, or a film member that deforms and generates displacement by electrical driving. Specifically, there are an electrostrictive film, a composite material (a material obtained by resin-molding piezoelectric ceramics), an electrically driven elastomer, or a liquid crystal elastomer.

  The “film that deforms in the plane direction when a voltage is applied” can also be realized by using piezoelectric ceramics and a plurality of exciter films. In this case, each of the plurality of exciter films has one end connected to the piezoelectric ceramic and the other end connected to the diaphragm.

DESCRIPTION OF SYMBOLS 10 ... Tactile sense presentation apparatus 20A, 20B ... Piezoelectric film 30A, 30B ... Exciter films 40, 40A, 40B ... Diaphragm 50, 50B ... Touch panel 60 ... Adhesive layer 70 ... Frame 80 ... Touch sensor 81 ... Drive part 200 ... Base film 201A , 201B ... electrodes

Claims (10)

A film that deforms in the surface direction by applying voltage;
A flat diaphragm fixed to the film in a state where bending stress is generated;
A touch detection unit for detecting a touch operation;
A drive unit that applies a drive signal to the film when the touch detection unit detects a touch operation;
The tactile sensation presentation apparatus, wherein the film is disposed so as to wrap around both main surfaces of the diaphragm via an end portion of the diaphragm.   The tactile sensation presentation apparatus according to claim 1, wherein an end portion of the diaphragm has a curved surface shape without corners.   The tactile sense presentation device according to claim 1, wherein the touch detection unit is realized by a touch panel attached to the diaphragm.   4. The tactile presentation device according to claim 1, wherein the diaphragm is fixed to the film while being curved in a direction orthogonal to a main surface of the film. .   The vibration plate has a shape in which a flat plate surface is curved when not fixed to the film, and is fixed to the film so that the curved flat plate surface is flat. The tactile sense presentation device according to claim 3.   6. The tactile presentation device according to claim 1, wherein a plurality of the films are attached.   The tactile sensation presentation apparatus according to claim 1, wherein the film includes a piezoelectric film in which an electrode and a piezoelectric resin are laminated.   The tactile sensation presentation apparatus according to claim 7, wherein the piezoelectric resin is made of polyvinylidene fluoride.   The tactile sensation presentation apparatus according to claim 7, wherein the piezoelectric resin is made of a chiral polymer.   The tactile sensation presentation apparatus according to claim 9, wherein the chiral polymer is made of polylactic acid.

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