JP2014013001A - Piezoelectric fan - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric fan that can decrease the number of wiring members connected to a piezoelectric element constituting a bimorph vibrator.SOLUTION: A piezoelectric fan includes: piezoelectric elements 12A and 13A arranged on both flat plate surfaces of a vibration plate 11A so as to extend from a vane part 111A to a base part 110A; conductive electrode plates 14A and 15A having one ends arranged at positions opposed to the base part 111A of the piezoelectric elements 12A and 13A, and the other ends arranged at positions opposed to each other outside the vibration plate 11A; an electrode connection plate 18A provided at a position opposed to the conductive electrode plates 14A and 15A outside the vibration plate 11A, and electrically connecting between the conductive electrode plates 14A and 15A; and support bodies 16A and 17A supporting the vibration plate 11A, piezoelectric elements 12A and 13A, conductive electrode plates 14A and 15A, and electrode connection plate 18A.

Description

  The present invention relates to a piezoelectric fan that blows air by driving and vibrating a piezoelectric element.

  2. Description of the Related Art In recent years, electronic devices that incorporate heat-generating components such as AV equipment and computers have often employed small and highly quiet piezoelectric fans for cooling (see, for example, Patent Document 1).

  FIG. 8 is a side cross-sectional view for explaining a conventional configuration example of a piezoelectric fan with reference to Patent Document 1.

  A piezoelectric fan 1P shown in FIG. 8A includes an elastic metal plate 11P, a piezoelectric element 12P, a piezoelectric element 13P, an adhesive layer 14P, an adhesive layer 15P, a support 16P, and a support 17P. Here, the upper direction in the drawing of FIG. 8A is the top surface direction, the lower direction in the drawing is the bottom surface direction, and the right direction in the drawing is the blowing direction. The flat plate surface in the top surface direction of the flat plate member is the top surface, and the flat plate surface in the bottom surface direction is the bottom surface.

  The elastic metal plate 11P is made of a metal having elasticity and is a flat plate that is long in the blowing direction. The piezoelectric fan 1P performs ventilation in the blowing direction by bending and vibrating the elastic metal plate 11P in the top surface direction and the bottom surface direction.

  The piezoelectric element 12P and the piezoelectric element 13P are configured by forming electrodes on the top and bottom surfaces of a plate-like piezoelectric body. The piezoelectric element 12P is in contact with the top surface of the elastic metal plate 11P. The piezoelectric element 12P is shorter in the blowing direction than the elastic metal plate 11P, and is arranged close to the blowing direction on the top surface of the elastic metal plate 11P. The piezoelectric element 13P is in contact with the bottom surface of the elastic metal plate 11P. The piezoelectric element 13P is shorter in the blowing direction than the elastic metal plate 11P and is disposed in a region facing the piezoelectric element 12P on the bottom surface of the elastic metal plate 11P. These piezoelectric elements 12P and 13P constitute a bimorph vibrator together with the elastic metal plate 11P.

  The support body 16P and the support body 17P are fixed to an external structure, for example, and sandwich the bimorph vibrator. Specifically, the support 16P is in contact with the top surface of the piezoelectric element 12P. The support body 16P is shorter in the blowing direction than the piezoelectric element 12P, and is arranged close to the blowing direction on the top surface of the piezoelectric element 12P. Further, the support 17P is in contact with the bottom surface of the piezoelectric element 13P. The support body 17P is shorter in the blowing direction than the piezoelectric element 13P, and is disposed in a region facing the support body 16P on the bottom surface of the piezoelectric element 13P.

  The piezoelectric element 12P and the piezoelectric element 13P are connected to and driven by an AC voltage source. Therefore, a wiring member such as a lead wire is connected to the piezoelectric fan 1P by soldering or the like.

  FIG. 8B is a diagram illustrating a general wiring mode with an AC voltage source.

  In this wiring mode, the first wiring member 31P is connected to the electrode on the top surface side of the piezoelectric element 12P. The second wiring member 32P is connected to the electrode on the bottom surface side of the piezoelectric element 13P. The first wiring member 31P and the second wiring member 32P are connected to the first terminal of the AC voltage source 30P. A third wiring member 33P is connected to the elastic metal plate 11P. The third wiring member 33P is connected to the second terminal of the AC voltage source 30P.

JP 2008-172106 A

  In the conventional wiring mode, when the piezoelectric fan 1P is driven, the piezoelectric element 12P and the piezoelectric element 13P are bent, so that a load is applied to the connection portion between the wiring members 31P and 32P and the piezoelectric elements 12P and 13P, and disconnection may occur. There is. Further, when the piezoelectric fan 1P is routed, the wiring members 31P, 32P, 33P may be caught by other members, which may cause disconnection. Thus, the risk of disconnection increases as the number of wiring members increases.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to realize a piezoelectric fan that reduces the number of wiring members connected to the piezoelectric elements constituting the bimorph vibrator and has less fear of disconnection between the piezoelectric elements and the wiring members.

  The piezoelectric fan of the present invention has the following characteristics. The piezoelectric fan includes a vibration plate, a first piezoelectric element, a second piezoelectric element, a first conductive electrode plate, a second conductive electrode plate, an electrode connection plate, and a support portion. I have. The diaphragm includes a base portion and a wing plate portion extending from the base portion. The first piezoelectric element is arranged on one main surface of the diaphragm so as to extend from the wing plate portion to the base portion. The second piezoelectric element is disposed on the other main surface of the diaphragm so as to extend from the blade portion to the base portion. One end of the first conductive electrode plate is disposed at a position facing the base portion on the surface opposite to the surface in contact with the diaphragm of the first piezoelectric element, and the other end is disposed outside the diaphragm. Yes. One end of the second conductive electrode plate is disposed at a position facing the base portion on the surface opposite to the surface in contact with the vibration plate of the second piezoelectric element. The other end is disposed at a position facing the conductive electrode plate. The electrode connection plate is directly supported by the one conductive electrode plate and the second conductive electrode plate, and electrically connects the first conductive electrode plate and the second conductive electrode plate. ing. The support part supports the base part via the first piezoelectric element and the second piezoelectric element.

  In this configuration, the first piezoelectric element and the second piezoelectric element are electrically connected via the first conductive electrode plate, the electrode connection plate, and the second conductive electrode plate. Therefore, the number of wiring members wired for connecting the first piezoelectric element and the second piezoelectric element to the AC voltage source can be reduced. Therefore, it is possible to reduce the concern that disconnection occurs at the connection portion of the wiring member.

  In the above-described piezoelectric fan, the first wiring member connected to the voltage source is preferably connected to any one of the first conductive electrode plate, the electrode connection plate, and the second conductive electrode plate. It is.

  In this configuration, by connecting the wiring member to the base portion, the first conductive electrode plate, the electrode connection plate, or the second conductive electrode plate, a load caused by vibration acts on the connection portion of the wiring member. It is possible to prevent the breakage and disconnection of the connecting portion of the wiring member more reliably.

  Furthermore, when the wiring member is soldered to the electrode of the piezoelectric element, the piezoelectric element is locally heated, so that local thermal stress is generated inside the piezoelectric element and the piezoelectric element is damaged. There is a risk, but by connecting the wiring member to the first conductive electrode plate, electrode connection plate, or second conductive electrode plate instead of the piezoelectric element, the piezoelectric element is damaged due to thermal stress at the time of wiring connection Can be prevented.

  In the above-described piezoelectric fan, the diaphragm includes a plurality of blade portions arranged in parallel to each other, and each of the plurality of blade portions is provided with a first piezoelectric element and a second piezoelectric element. It is preferable that adjacent slat portions vibrate in opposite phases.

  In this configuration, since the adjacent wing plate portions vibrate in opposite phases, vibrations transmitted from each wing plate portion to the base portion are canceled out. Therefore, it is possible to more reliably prevent vibration from propagating to the base portion, the first conductive electrode plate, the electrode connection plate, and the second conductive electrode plate.

  In the above-described piezoelectric fan, it is preferable that the first conductive electrode plate and the second conductive electrode plate each have a wiring pattern formed on a flexible substrate.

  With this configuration, a drive circuit can be formed. In addition, the flexible substrate that absorbs vibration more reliably prevents vibration from propagating to the base portion, the first conductive electrode plate, the electrode connection plate, and the second conductive electrode plate. be able to.

  In the above-described piezoelectric fan, the support portion includes a first support body and a second support body that support the first conductive electrode plate, the vibration plate, and the second conductive electrode plate, A first elastic member is provided between the support and the first conductive electrode plate, and a second elastic member is provided between the second support and the second conductive electrode plate. It is preferable.

  In this configuration, since the elastic member absorbs the irregularities on the surface of the support, the electrode of the piezoelectric element and the conductive electrode plate make better contact. As a result, the contact resistance between the electrode of the piezoelectric element and the conductive electrode plate is reduced, and a sufficient voltage can be applied to the piezoelectric element more reliably.

  According to this invention, since the first piezoelectric element and the second piezoelectric element are electrically connected via the first conductive electrode plate, the electrode connection plate, and the second conductive electrode plate, The number of wiring members connected to connect the first piezoelectric element and the second piezoelectric element to the AC voltage source can be reduced. Therefore, it is possible to reduce the concern that disconnection occurs at the connection portion of the wiring member.

1 is an external perspective view of a piezoelectric fan according to a first embodiment of the present invention. 1 is an exploded perspective view of a piezoelectric fan according to a first embodiment of the present invention. It is a three-view figure of the piezoelectric fan which concerns on the 1st Embodiment of this invention, (A) is a top view, (B) is a side view, (C) is a front view. It is a figure which shows the wiring aspect of the piezoelectric fan which concerns on the 1st Embodiment of this invention. It is a three-view figure of the piezoelectric fan which concerns on the 2nd Embodiment of this invention, (A) is a top view, (B) is a side view, (C) is a front view. It is a side view of the piezoelectric fan which concerns on the 3rd Embodiment of this invention. It is a side view of the piezoelectric fan which concerns on the 4th Embodiment of this invention. It is side surface sectional drawing which shows the structural example of the conventional piezoelectric fan.

  A piezoelectric fan according to a first embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is an external perspective view of a piezoelectric fan according to a first embodiment of the present invention. FIG. 2 is an exploded perspective view of the piezoelectric fan according to the first embodiment of the present invention. FIG. 3A is a plan view of the piezoelectric fan according to the first embodiment of the present invention viewed from the positive side in the Z-axis direction. FIG. 3B is a side view of the piezoelectric fan according to the first embodiment of the present invention viewed from the positive direction side in the X-axis direction. FIG. 3C is a front view of the piezoelectric fan according to the first embodiment of the present invention viewed from the positive side in the Y-axis direction.

  1 to 4, the longitudinal direction of the base portion 110 of the diaphragm 11 is defined as the X axis. Further, the longitudinal direction of the blade portion of the diaphragm 11 is defined as the Y axis. Further, a direction orthogonal to the flat plate surface of the diaphragm 11 is defined as the Z axis. The X axis, the Y axis, and the Z axis are orthogonal to each other.

  In the following description, the positive direction in the Z-axis direction is the top surface direction of the piezoelectric fan, the negative direction in the Z-axis direction is the bottom surface direction of the piezoelectric fan, the positive direction in the Y-axis direction is the blowing direction of the piezoelectric fan, and the X-axis direction. Is the right side direction of the piezoelectric fan. The flat plate surface in the top surface direction of the flat plate member is the top surface, and the flat plate surface in the bottom surface direction is the bottom surface.

  The piezoelectric fan 1 according to the first embodiment includes a diaphragm 11, piezoelectric elements 121, 122, 123, 131, 132, 133, conductive electrode plates 14, 15, supports 16, 17, and an electrode connection plate 18. It has.

  The diaphragm 11 is a metal flat plate having predetermined elasticity, and is made of, for example, stainless steel having a thickness of 0.1 mm. The diaphragm 11 is formed by integrally forming a base portion 110 and three wing plate portions 111, 112, and 113.

  The base portion 110 is long in the right side surface direction orthogonal to the air blowing direction, and connects the wing plate portion 112, the wing plate portion 111, and the wing plate portion 113. The base portion 110 includes a wiring attachment portion 114 that protrudes in the right side direction from the connection position with the slat portion 113. The wiring attachment portion 114 is an area where a wiring member such as a lead wire is soldered later.

  Each of the wing plate portions 111, 112, and 113 has one end portion facing the blowing direction as a free end, and the other end portion facing the opposite direction to the blowing direction is connected to the base portion 110. That is, the wing plate portions 111, 112, and 113 are cantilever beams that extend in the air blowing direction from the connection position with the base portion 110 and have a fixed end at the free end side in the region sandwiched between the supports 16 and 17. It is composed. The wing plate portions 111, 112, and 113 include a wide portion 115 and a narrow portion 116. The wide portion 115 is a portion having a predetermined length provided on the free end side of each of the wing plate portions 111, 112, 113, and is configured to be wider than the narrow portion 116 here. The narrow portion 116 is a portion provided on the fixed end side with respect to the wide portion 115 of each of the wing plate portions 111, 112, 113, and is configured to be narrower than the wide portion 115 here. The wing plate portions 111, 112, and 113 are arranged in the order of the wing plate portion 112, the wing plate portion 111, and the wing plate portion 113 at predetermined intervals along the right side surface direction. The wing plate portions 112 and 113 arranged on both sides are formed in substantially the same shape. The length of the wing plate portion 111 disposed in the center in the X-axis direction is approximately twice that of the wing plate portions 112 and 113. The lengths of the wing plate portions 111, 112, 113 in the Y-axis direction are substantially the same. The piezoelectric fan 1 is bent in the top surface direction and the bottom surface direction so that adjacent ones of the blade portions 111, 112, 113 vibrate in opposite phases, and blows air in the blowing direction.

  Each of the piezoelectric elements 121, 122, 123, 131, 132, and 133 has a rectangular flat plate shape, and is formed on a top surface and a bottom surface of a piezoelectric body made of, for example, a lead zirconate titanate ceramic. Electrodes (both not shown). The electrode formed on the flat plate surface in contact with the piezoelectric diaphragm 11 is an electrode for grounding. The electrode formed on the flat plate surface opposite to the flat plate surface in contact with the diaphragm 11 is an electrode for applying a drive signal. In the case where the diaphragm 11 is a conductor, the electrode on the diaphragm 11 side of the piezoelectric body can be omitted, and the diaphragm 11 is grounded.

  The piezoelectric element 121 is arranged on the top surface of the diaphragm 11 so as to extend from the wing plate portion 111 to the base portion 110. The piezoelectric element 131 is disposed on the bottom surface of the diaphragm 11 so as to extend from the wing plate portion 111 to the base portion 110. More specifically, as shown in FIGS. 3 (A) and 3 (B), the piezoelectric elements 121 and 131 cover the narrow portion 116 in the wing plate portion 111 and end the blowing direction in the base portion 110. From, it is attached so that the area | region extended to the middle of the base part 110 in the reverse direction to the ventilation direction may be covered. Further, as indicated by white arrows in FIG. 3C, the polarization direction of the piezoelectric elements 121 and 131 is the top surface direction.

  The piezoelectric element 121 corresponds to the first piezoelectric element in the present invention, and the piezoelectric element 131 corresponds to the second piezoelectric element in the present invention.

  The piezoelectric element 122 is arranged on the top surface of the diaphragm 11 so as to extend from the wing plate portion 112 to the base portion 110. The piezoelectric element 132 is disposed on the bottom surface of the diaphragm 11 so as to extend from the wing plate portion 112 to the base portion 110. More specifically, as shown in FIGS. 3 (A) and 3 (B), the piezoelectric elements 122 and 132 cover the narrow portion 116 in the wing plate portion 112 and end in the air blowing direction in the base portion 110. From, it is attached so that the area | region extended to the middle of the base part 110 in the reverse direction to the ventilation direction may be covered. Further, as indicated by white arrows in FIG. 3C, the polarization direction of the piezoelectric elements 122 and 132 is the bottom surface direction.

  The piezoelectric element 122 corresponds to the first piezoelectric element in the present invention, and the piezoelectric element 132 corresponds to the second piezoelectric element in the present invention.

  The piezoelectric element 123 is arranged on the top surface of the diaphragm 11 so as to extend from the wing plate portion 113 to the base portion 110. The piezoelectric element 133 is disposed on the bottom surface of the diaphragm 11 so as to extend from the wing plate portion 113 to the base portion 110. More specifically, as shown in FIGS. 3 (A) and 3 (B), the piezoelectric elements 123 and 133 cover the narrow portion 116 in the wing plate portion 113 and end the blowing direction in the base portion 110. From, it is attached so that the area | region extended to the middle of the base part 110 in the reverse direction to the ventilation direction may be covered. Further, as indicated by white arrows in FIG. 3C, the polarization direction of the piezoelectric elements 123 and 133 is the bottom surface direction.

  The piezoelectric element 123 corresponds to the first piezoelectric element in the present invention, and the piezoelectric element 133 corresponds to the second piezoelectric element in the present invention.

  Each of the conductive electrode plates 14 and 15 has a rectangular flat plate shape that is long in the right side direction orthogonal to the blowing direction. For example, the conductive electrode plates 14 and 15 have a metal plate, a printed circuit board on which a wiring pattern is formed, or a wiring pattern. It consists of the formed flexible printed circuit board. The conductive electrode plate 14 is attached across the top surface of the piezoelectric elements 121, 122, 123 facing the base portion 110 and the top surface of the electrode connection plate 18. The top electrode and the electrode connection plate 18 are electrically connected to each other. The conductive electrode plate 15 is attached across the bottom surface of the piezoelectric elements 131, 132, 133 facing the base portion 110 and the bottom surface of the electrode connection plate 18. The electrode and the electrode connection plate 18 are electrically connected to each other. More specifically, as shown in FIGS. 3A and 3B, the conductive electrode plates 14 and 15 are opposite to the blowing direction in the base portion 110 from the end in the blowing direction in the base portion 110. It is attached to a region extending beyond the end of the direction to the outside of the base part 110. The conductive electrode plate 14 corresponds to the first conductive electrode plate in the present embodiment, and the conductive electrode plate 15 corresponds to the second conductive electrode plate in the present embodiment.

  The electrode connection plate 18 is a rectangular flat plate elongated in the right side surface direction orthogonal to the blowing direction, and is made of, for example, a metal plate or a substrate on which a wiring pattern and a via electrode are formed. The electrode connection plate 18 is attached between the bottom surface of the conductive electrode plate 14 and the top surface of the conductive electrode plate 15 at a position away from the vibration plate 11 in the direction opposite to the blowing direction. 14 and the conductive electrode plate 15 are electrically connected. Accordingly, the top electrode of each of the piezoelectric elements 121, 122, and 123 and the bottom electrode of each of the piezoelectric elements 131, 132, and 133 are connected to the conductive electrode plate 14, the electrode connection plate 18, and the conductive electrode plate 15. Conducted through.

  The electrode connection plate 18 and the conductive electrode plates 14 and 15 are attached by, for example, a conductive adhesive, but may be fixed by screwing or welding.

  Each of the supports 16 and 17 has a rectangular flat plate shape that is long in the right side direction orthogonal to the air blowing direction, and is made of an insulating material such as glass epoxy resin. The support 16 is fixed to an external structure (not shown), and is attached to the top surface of the conductive electrode plate 14. The support body 17 is fixed to an external structure (not shown), and is attached to the bottom surface of the conductive electrode plate 15. More specifically, as shown in FIGS. 3A and 3B, the supports 16 and 17 have substantially the same planar shape as the base portion 110 of the diaphragm 11. In other words, the supports 16 and 17 are arranged to extend in the direction opposite to the blowing direction from at least the end of the base portion 110 in the blowing direction. The supports 16 and 17 constitute a support part in the present embodiment, and include the conductive electrode plate 14, the piezoelectric elements 121, 122, 123, the vibration plate 11, the piezoelectric elements 131, 132, 133, and the electrode connection plate 18. A laminate composed of the conductive electrode plate 15 is sandwiched. More specifically, the supports 16 and 17 are attached so as to cover the entire surface of the piezoelectric elements 121, 122, 123, 131, 132, and 133 that overlap the base portion 110.

  In addition, the position of the edge of the support bodies 16 and 17 and the conductive electrode plate 14 in the ventilation direction and the position of the edge of the ventilation direction of the base part 110 are made to correspond here. However, these positions do not necessarily coincide with each other, and the positions of the supports 16 and 17 and the conductive electrode plate 14 in the air blowing direction may overlap with the wing plate portions 111, 112, and 113. However, it is preferable that the positions of the ends of the support bodies 16 and 17 in the blowing direction coincide with the positions of the ends of the conductive electrode plate 14 in the blowing direction.

  FIG. 4 is a diagram for explaining a wiring mode with the AC voltage source of the piezoelectric fan according to the first embodiment of the present invention.

  A lead wire 31 connected to the first terminal of the AC voltage source is soldered to the conductive electrode plate 14. A lead wire 32 connected to the second terminal of the AC voltage source is soldered to the wiring attachment portion 114 of the diaphragm 11.

  The conductive electrode plate 14 is electrically connected to electrodes (not shown) on the top surface side of the piezoelectric elements 121, 122, and 123, and is electrically connected via the electrode connection plate 18 and the conductive electrode plate 15. It is also electrically connected to the electrodes (not shown) on the bottom side of the elements 131, 132, 133. The diaphragm 11 is also electrically connected to electrodes (not shown) on the bottom surfaces of the piezoelectric elements 121, 122, and 123, and electrodes on the top surface of the piezoelectric elements 131, 132, and 133 (not shown). )). Therefore, the piezoelectric elements 121, 122, 123, 131, 132, 133 are connected in parallel between the lead wire 31 and the lead wire 32.

  For this reason, in the piezoelectric elements 121, 122, and 123 and the piezoelectric elements 131, 132, and 133, the alternating voltage applied from the top electrode to the bottom electrode has an opposite phase. Of the piezoelectric elements 121, 122, 123, 131, 132, and 133, two piezoelectric elements that are provided facing the diaphragm 11 are polarized with respect to each other as shown in FIG. Therefore, in the piezoelectric elements 121, 122, and 123 and the piezoelectric elements 131, 132, and 133, the bending phase when a voltage is applied is also reversed. Therefore, in the piezoelectric fan 1, the piezoelectric elements 121 and 131 and the wing plate portion 111 provided to face the diaphragm 11 constitute a first bimorph vibrator. In addition, the piezoelectric elements 122 and 132 and the wing plate portion 112 provided to face the diaphragm 11 constitute a second bimorph vibrator. In addition, the piezoelectric elements 123 and 133 and the wing plate portion 113 provided to face the diaphragm 11 constitute a third bimorph vibrator. Since each bimorph vibrator is fixedly supported by the support body 16 and the support body 17, it vibrates in the top surface direction and the bottom surface direction. As a result, the wing plate portions 111, 112, and 113 swing and air is blown in the blowing direction.

  In this piezoelectric fan 1, the conductive electrode plate 14, the electrode connection plate 18, and the conductive electrode plate 15 are composed of the top electrode of each of the piezoelectric elements 121, 122, 123 and the bottom surface of each of the piezoelectric elements 131, 132, 133. Since the wiring path for electrically connecting the electrodes of the AC voltage source to the piezoelectric elements 121, 122, 123, 131, is formed by simple wiring via the single lead wire 31. Connection with 132,133 is realizable.

  That is, all the piezoelectric elements 121, 122, 123, 131, 132, 133 can be connected to the AC voltage source by using only the two lead wires 31, 32. Therefore, the number of lead wires required can be minimized, and the concern that the lead wires 31 and 32 are caught by other members and disconnected can be reduced. In addition, the number of times of soldering can be minimized, and wiring work is facilitated.

  Further, the piezoelectric elements 121, 122, 123, 131, 132, 133 are sandwiched between the diaphragm 11 and the conductive electrode plates 14, 15, and the piezoelectric elements 121, 122, 123, 131, 132, 133 are configured. In addition, since it is not necessary to solder the lead wire 31 directly, it is possible to reduce the concern that the piezoelectric elements 121, 122, 123, 131, 132, 133 are damaged by the thermal stress at the time of wiring connection.

  In addition, since the conductive electrode plates 14 and 15 are joined to each other via the electrode connection plate 18, the support state of the conductive electrode plates 14 and 15 is stabilized, and there is little fear of disconnection, and the conductive electrode There is no possibility that the plates 14 and 15 and the diaphragm 11 are short-circuited.

  In the piezoelectric fan 1, the lead wire 31 is connected to the conductive electrode plate 14 on the side opposite to the free end from the fixed end of the wing plate portions 111, 112, 113. Less vibration is applied. That is, it is possible to reduce the concern that the solder portion is loaded and disconnected due to the bending vibration of the piezoelectric elements 121, 122, 123, 131, 132, and 133.

  Further, the first bimorph vibrator has an anti-phase vibration with respect to the second bimorph vibrator and the third bimorph vibrator, and in the piezoelectric fan 1, vibration transmitted from each bimorph vibrator to the base unit 110 is canceled out. The electrode connection plate 18, the conductive electrode plate 14, and the conductive electrode plate 15 hardly vibrate. As a result, the leakage of vibration from the base portion 110 to the electrode connection plate 18, the conductive electrode plate 14, and the conductive electrode plate 15 is greatly suppressed, and the fear that the solder portion is loaded and disconnected is greatly reduced. be able to.

  Furthermore, when the conductive electrode plates 14 and 15 are formed of a flexible flexible substrate, vibrations can be absorbed by the flexible substrate, and the electrode connection plate 18, the conductive electrode plate 14, and The conductive electrode plate 15 hardly vibrates. This also greatly suppresses the leakage of vibration from the base portion 110 to the electrode connection plate 18, the conductive electrode plate 14, and the conductive electrode plate 15, and greatly increases the concern that the solder portion is loaded and disconnected. Can be reduced.

  In addition, in the piezoelectric fan 1, the support bodies 16 and 17, the conductive electrode plates 14 and 15, and the electrode connection plate 18 are each constituted by separate plate-like members, and the first to third bimorph vibrations are provided. It is configured to support the child surface. As a result, the conductive electrode plates 14 and 15 and the electrode connection plate 18 are integrally formed, and the first to third bimorph vibrators are clamped with a high clamping force as compared with the case where the wire support is performed with a configuration like a spring clamp. can do. As a result, variations in contact resistance between the respective plate-like piezoelectric elements 121, 122, 123, 131, 132, 133 and the conductive electrode plates 14, 15 are suppressed, and the piezoelectric fan 1 has high stability and high reliability. You can have it.

  Next, a piezoelectric fan according to a second embodiment of the present invention will be described with reference to FIG. FIG. 5A is a plan view of a piezoelectric fan according to the second embodiment of the present invention. FIG. 5B is a side view of the piezoelectric fan according to the second embodiment of the present invention. FIG. 5C is a front view of the piezoelectric fan according to the second embodiment of the present invention.

  A piezoelectric fan 1A according to the second embodiment of the present invention includes a diaphragm 11A, piezoelectric elements 12A and 13A, conductive electrode plates 14A and 15A, supports 16A and 17A, and an electrode connection plate 18A.

  The diaphragm 11A includes a base portion 110A and one wing plate portion 111A. The wing plate portion 111A is connected to the base portion 110A and extends in the blowing direction from a connection position with the base portion 110A. The wing plate portion 111A constitutes a cantilever having one end facing the air blowing direction as a free end and a free end in a region sandwiched between the supports 16A and 17A as a fixed end.

  110 A of base parts are provided with the wiring attachment part 114A which protrudes in the right side surface direction rather than the position where the blade part 111A is connected. The wiring attachment portion 114A is an area where a wiring member such as a lead wire is soldered later.

  The piezoelectric element 12A is arranged on the top surface of the vibration plate 11A so as to extend from the wing plate portion 111A to the base portion 110A. The piezoelectric element 13A is disposed on the bottom surface of the vibration plate 11A so as to extend from the wing plate portion 111A to the base portion 110A. As indicated by white arrows in FIG. 5C, the polarization direction of the piezoelectric elements 12A and 13A is the top surface direction. The piezoelectric element 12A, the piezoelectric element 13A, and the diaphragm 11A constitute a bimorph vibrator in which the diaphragm 11A is fixed between the piezoelectric element 12A and the piezoelectric element 13A.

  The conductive electrode plate 14A is disposed across the top surface of the piezoelectric element 12A facing the base portion 110A and the top surface of the electrode connection plate 18A. The conductive electrode plate 15A is disposed across the bottom surface of the piezoelectric element 13A at a position facing the base portion 110A and the bottom surface of the electrode connection plate 18A. Specifically, the conductive electrode plates 14A and 15A extend from the end in the blowing direction in the base portion 110A to the outside of the base portion 110A beyond the end in the direction opposite to the blowing direction in the base portion 110A. It is attached.

  The electrode connection plate 18A is attached between the bottom surface of the conductive electrode plate 14A and the top surface of the conductive electrode plate 15A at a position away from the vibration plate 11 in the direction opposite to the blowing direction. 14A is electrically connected to the conductive electrode plate 15A.

  Each of the supports 16A and 17A has a rectangular flat plate shape elongated in the right side direction orthogonal to the air blowing direction, and is made of an insulating material such as glass epoxy resin. The support 16A is fixed to an external structure (not shown). The support 16A is disposed on the top surface of the conductive electrode plate 14A so as to extend in the direction opposite to the blowing direction from at least the end of the base portion 110A in the blowing direction. The support 17A is disposed on the bottom surface of the conductive electrode plate 15A so as to extend at least from the end in the blowing direction in the base portion 110A in the direction opposite to the blowing direction. More specifically, the supports 16A and 17A are attached so as to cover the entire surface of the piezoelectric elements 12A and 13A that overlap the base portion 110A.

  Even in the piezoelectric fan 1A configured as described above, a wiring member such as a lead wire connected to the voltage source is connected to any one of the conductive electrode plate 14A, the conductive electrode plate 15A, and the electrode connection plate 18A. The bimorph vibrator constituted by the vibration plate 11A and the piezoelectric elements 12A and 13A is connected to 114A, and the wing plate portion 111A is flexibly vibrated to blow air.

  That is, all the piezoelectric elements 121, 122, 123, 131, 132, 133 can be connected to an AC voltage source by using only two lead wires, and the number of necessary lead wires can be minimized.

  Next, a piezoelectric fan according to a third embodiment of the present invention will be described with reference to FIG. FIG. 6 is a side view of a piezoelectric fan according to the third embodiment of the present invention.

  The piezoelectric fan 1B according to the third embodiment of the present invention is different from the piezoelectric fan 1A shown in the second embodiment in the position where the conductive electrode plate is fixed. Other configurations are substantially the same as those of the piezoelectric fan 1A shown in the second embodiment.

  Specifically, the piezoelectric fan 1B includes a vibration plate 11B, piezoelectric elements 12B and 13B, conductive electrode plates 14B and 15B, supports 16B and 17B, and an electrode connection plate 18B.

  Each of the supports 16B and 17B has a rectangular flat plate shape elongated in the right side direction orthogonal to the blowing direction, and is made of an insulating material such as glass epoxy resin. The support bodies 16B and 17B have a shape in which the width in the air blowing direction is narrower than that of the piezoelectric elements 12B and 13B, and extend from the end of the base portion 110B in the air blowing direction in the direction opposite to the air blowing direction to be a part of the base portion 110B. The piezoelectric element 12B, the diaphragm 11B, and the piezoelectric element 13B are sandwiched. More specifically, the supports 16B and 17B directly support a part of the piezoelectric elements 12B and 13B overlapping the base portion 110B.

  The conductive electrode plates 14B and 15B are disposed on the side opposite to the blowing direction from the supports 16B and 17B, respectively. Specifically, the conductive electrode plates 14B and 15B are fixed to the piezoelectric elements 12B and 13B on the side opposite to the air blowing direction from the supports 16B and 17B. The conductive electrode plates 14B and 15B extend in the direction opposite to the air blowing direction from the ends opposite to the air blowing directions of the piezoelectric elements 12B and 13B and the vibration plate 11B. Thus, it is joined to the electrode connection plate 18B.

  The present invention can be realized even with the configuration of the piezoelectric fan 1B, and the electrodes of the two piezoelectric elements 12B and 13B constituting the bimorph vibrator are connected to the conductive electrode plates 14B and 15B and the electrode connection plate. By electrically connecting with 18B, the number of wiring members connected to the two piezoelectric elements 12B and 13B constituting the bimorph vibrator can be reduced.

  Next, a piezoelectric fan according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 7 is a side view of a piezoelectric fan according to the fourth embodiment of the present invention.

  The piezoelectric fan 1C according to the fourth embodiment of the present invention is different from the piezoelectric fan 1A shown in the second embodiment in that it further includes elastic plates 19C and 20C. Other configurations are substantially the same as those of the piezoelectric fan 1A shown in the second embodiment.

  Specifically, the piezoelectric fan 1C includes a vibration plate 11C, piezoelectric elements 12C and 13C, conductive electrode plates 14C and 15C, supports 16C and 17C, an electrode connection plate 18C, and elastic plates 19C and 20C.

  The elastic plates 19C and 20C have substantially the same shape as the supports 16C and 17C, respectively, and are made of a flat plate made of an elastic body such as silicone rubber. The elastic plate 19C is provided on the top surface side of the vibration plate 11C, and is specifically sandwiched between the top surface of the conductive electrode plate 14C and the bottom surface of the support 16C. The elastic plate 20C is provided on the bottom surface side of the vibration plate 11C. Specifically, the elastic plate 20C is sandwiched between the bottom surface of the conductive electrode plate 15C and the top surface of the support 17C.

  In the piezoelectric fan 1C having such a configuration, the elastic plates 19C and 20C absorb the irregularities on the surfaces of the supports 16C and 17C and the conductive electrode plates 14C and 15C, so the electrodes of the piezoelectric elements 12C and 13C and the conductive electrode plate 14C and 15C come into better contact. As a result, the contact resistance between the electrodes of the piezoelectric elements 12C and 13C and the conductive electrode plates 14C and 15C is reduced, and a sufficient voltage can be reliably applied to the piezoelectric elements 12C and 13C.

  In each of the embodiments described above, the piezoelectric element is composed of, for example, lead zirconate titanate ceramics, but is not limited thereto. For example, it may be composed of a lead-free piezoelectric ceramic material such as potassium sodium niobate and alkali niobate ceramics.

  In the above description, an embodiment in which three slats or one slat is provided is shown, but the present invention is not limited by the number of slats. Moreover, although the embodiment in which the polarization directions of the piezoelectric bodies constituting the adjacent bimorph vibrators are made different has been shown, the polarization directions of the piezoelectric bodies constituting the adjacent bimorph vibrators are made to coincide with each other, and the adjacent bimorph vibrations are arranged. The child may be vibrated in the same phase.

  In the above description, the embodiment in which the bimorph vibrator is sandwiched between the two supports is shown. However, the bimorph vibrator may be fixed and supported by some fixing method, for example, by another method such as adhesion. Good. In that case, the number of supports may be one.

1, 1A, 1B, 1C ... piezoelectric fans 11, 11A, 11B, 11C ... diaphragms 110, 110A ... base portions 111, 112, 113, 111A ... wing plate portions 114, 114A ... wiring attachment portions 121, 122, 123, 131, 132, 133, 12A, 13A, 12B, 13B, 12C, 13C ... piezoelectric elements 14, 15, 14A, 15A, 14B, 15B, 14C, 15C ... conductive electrode plates 16, 17, 16A, 17A, 16B, 17B, 16C, 17C ... Supports 18, 18A, 18B, 18C ... Electrode connection plates 19C, 20C ... Elastic plates

Claims (5)

A diaphragm having a base part and a slat part extending from the base part;
A first piezoelectric element disposed on one main surface of the diaphragm extending from the wing plate portion to the base portion;
A second piezoelectric element disposed on the other main surface of the diaphragm extending from the wing plate portion to the base portion;
A first conductive element having one end disposed at a position facing the base portion on a surface opposite to the surface in contact with the diaphragm of the first piezoelectric element and the other end disposed outside the diaphragm. A conductive electrode plate;
One end of the second piezoelectric element is disposed at a position facing the base portion on a surface opposite to the surface in contact with the diaphragm, and is outside the diaphragm, and is located on the first conductive electrode plate. A second conductive electrode plate having the other end disposed at a position opposite to
The first conductive electrode plate and the second conductive electrode plate are directly supported by the first conductive electrode plate and the second conductive electrode plate to electrically connect the first conductive electrode plate and the second conductive electrode plate. An electrode connection plate;
A support part for supporting the base part via the first piezoelectric element and the second piezoelectric element;
A piezoelectric fan comprising:   The first wiring member connected to the voltage source is connected to any one of the first conductive electrode plate, the electrode connection plate, and the second conductive electrode plate. The piezoelectric fan described. The diaphragm includes a plurality of the blade portions arranged in parallel to each other,
The first piezoelectric element and the second piezoelectric element are provided on each of the plurality of blade portions,
The piezoelectric fan according to claim 1 or 2, wherein the adjacent blade portions vibrate in opposite phases.   The first conductive electrode plate and the second conductive electrode plate are each formed by forming a wiring pattern on a flexible substrate. Piezoelectric fan. The support portion includes a first support and a second support that support the first conductive electrode plate, the diaphragm, and the second conductive electrode plate,
A first elastic member is provided between the first support and the first conductive electrode plate, and a second elastic member is provided between the second support and the second conductive electrode plate. The piezoelectric fan according to claim 1, wherein an elastic member is provided.

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