JP4981427B2 - Vibration drive device - Google Patents

Description

  The present invention relates to a vibration driving device that applies a driving force to a contact moving member by transmitting the vibration of the vibrating member to a contact moving member that contacts the vibrating member, and in particular, two vibration members via the contact moving member. The present invention relates to a vibration drive device arranged to face each other.

  Conventionally, a counter-type vibration driving device has been developed in which two vibrating bodies having the same structure are arranged to face each other via a contact moving member (see Patent Documents 1, 2, 3, 4, and 5). In the opposed type vibration drive device, in general, the same vibration is excited by supplying electric power to the two vibrating bodies in the same form, and the contact moving member is driven by transmitting this vibration to the contact moving member. is doing.

Further, the opposed type vibration drive device is generally configured so that the vibrations transmitted from the two vibrating bodies to the contact moving member are in opposite directions to cancel the vibrations, and bending vibration stress is applied to the contact moving member. Is never added. Therefore, the contact moving member can be configured in a thin plate shape or a sheet shape with low rigidity, and the apparatus can be miniaturized.
JP-A-2-214475 JP-A-3-23143 Japanese Patent Laid-Open No. 3-259841 Japanese Patent Laid-Open No. 11-346487 JP 2000-350481 A

  In Patent Documents 1 to 3, as described above, the vibrations from the two vibrators cancel each other, but the vibrations transmitted from the support portions of the vibrators to the support end do not cancel each other. For this reason, there has been a problem that vibrations propagate from the support end of the support portion of the vibrating body to the surroundings to generate vibration noise.

  Further, in Patent Documents 4 and 5, since the vibrating body vibrates vertically and the supporting member of the vibrating body extends from the center of symmetry, the supporting member does not vibrate, and from the support end of the supporting member. Vibration does not propagate around and does not emit vibration sound.

  However, in Patent Documents 4 and 5, none of the uppermost and lowermost contact moving members cancels vibrations propagated from the vibrating body. For this reason, the uppermost and lowermost contact moving members are required to have a large rigidity and have been increased in size. Further, the supporting function of the vibrating body, the spring function for obtaining the pressure contact force between the vibrating body and the contact moving member, and the power feeding function for applying a voltage to the piezoelectric ceramic are realized by separate components. For this reason, the number of parts around the vibrating body is increased, the structure is complicated, and the cost is high.

  The present invention has been made under such a background, and an object of the present invention is to provide a vibration drive device that can suppress the generation of vibration noise as much as possible with a simple configuration.

In order to achieve the above object, according to the present invention, two vibrating bodies are arranged to face each other via a contact moving member, and the two vibrating bodies are vibrated by power supply to apply a driving force to the contact moving member. In the vibration drive device, the two vibrating bodies are support members for attaching and supporting the vibrating body to other members, and are extended from a region of the electro-mechanical energy conversion element constituting the vibrating body. An extension portion is formed, and the extension portion supplies electric power to the electromechanical energy conversion element, and is electrically and mechanically connected to the extension portion of the other supporting member facing the extension portion. by a support member formed by said by the power supply to the extended portion of the two vibrator, Ri vibration displacement of the two vibrators Do and mirror-symmetrical with respect to the contact moving member, the electro - mechanical energy The conversion elements are positive and negative respectively Is divided into a plurality of regions polarization polarity is applied, the support member and the extended portion, characterized that you have more provided so as to supply power according to the positive and negative polarization polarity of the plurality of regions And

  The extending portions of the opposing supporting members of the two vibrating bodies are electrically and mechanically connected to the extending portions of the other opposing supporting member, and the vibration displacement of the two vibrating bodies is the contact movement. Mirror symmetry with respect to the member. In other words, the vibrations transmitted from the two vibrating bodies to the extending portion of the support member act so as to cancel each other. In addition, since the extending portions of the supporting members facing each other of the two vibrators are electrically and mechanically connected to each other, it is possible to perform at least a supporting function and a power feeding function, thereby reducing the number of parts. This contributes to the simplification of the structure.

  Therefore, according to the present invention, it is possible to provide a vibration drive device that can suppress the generation of vibration sound as much as possible with a simple configuration.

[First Embodiment]
FIG. 1 is an exploded perspective view illustrating the vibration mechanism of the vibration driving device according to the first embodiment of the invention.

As shown in FIG. 1, in this vibration mechanism, two vibrating bodies 5 having the same structure are arranged in an opposed state with the contact moving member 4 interposed therebetween. The shape of the contact moving member 4 is a round bar shape.
The vibrating body 5 has a rectangular plate-like elastic body 1 and piezoelectric ceramics 2 bonded to each other. The two vibrating bodies 5 are arranged so that the elastic body 1 is located on the contact moving body 4 side. A protrusion 1 a is formed on the outer surface of the elastic body 1, that is, the surface facing the contact moving member 4. The vibrating body 5 comes into contact with the contact moving member 4 via the protrusion 1a and transmits the vibration to the contact moving member 4, thereby moving the contact moving member 4 linearly (linearly).

  The piezoelectric ceramic 2 is a kind of electro-mechanical energy conversion element, and a thin plate-like support member 3 is attached to the outer surface thereof. The support member 3 is formed of a conductive spring member, and has an extending portion 3a that extends from the region of the piezoelectric ceramic 2 integrated with the elastic body 1 by bonding. A hole 3c is formed in the end 3b of the extension 3a. This hole 3c is formed in order to attach the supporting member 3 having a spring property to some other member and bring the vibrating body 5 into contact with the contact moving body 4 in a separable form.

  The support member 3 also has a power supply function for supplying a voltage to the piezoelectric ceramic 2 to excite mechanical vibration. That is, the support member 3 supplies a support function for supporting the vibrating body 5, a spring function for bringing the vibrating body 5 into contact with the contact moving member 4 in a separable form, and electrical energy for obtaining mechanical vibration. It also has a power feeding function. Therefore, a pressure member, a power supply wiring, and the like that are separately required in the past are unnecessary, and it is possible to reduce the size and weight.

  The piezoelectric ceramic 2 has a region divided into two in the moving direction of the contact moving member 4. The structure of the piezoelectric ceramic, the speed control method based on the phase of the supplied voltage, and the like are the same as those disclosed in JP-A-2004-320846.

  FIG. 2 shows the relationship between the structure of the piezoelectric ceramic 2 and the polarization polarity of the electrode of the piezoelectric ceramic 2 connected to the support member 3 as a power supply member.

  The piezoelectric ceramic 2 is composed of a plurality of layers of piezoelectric ceramics and electrodes. A broken line shown in FIG. 2 is an internal electrode 2a, and the internal electrode 2a is divided into an A region and a B region. The four black dots 2b shown in FIG. 2 are end faces of through holes that communicate with the internal electrode 2a.

  The through hole 2b (A +) is connected to an electrode having a positive polarization polarity in the A region. The through hole 2b (A−) is connected to an electrode having a negative polarization polarity in the A region. The through hole 2b (B +) is connected to an electrode having a positive polarization polarity in the B region. The through hole 2b (B−) is connected to an electrode having a negative polarization polarity in the B region. The individual display of the positive and negative electrodes in these internal electrodes 2a is not shown.

  The support member 3 is joined to the surface of the piezoelectric ceramic 2 with an adhesive or the like, and is electrically connected to the end surface of the through hole with a conductive paint (not shown). Specifically, the through hole 2b (A +) is connected to the support member 3 labeled “A +”, and the through hole 2b (A−) is connected to the support member 3 labeled “A−”. ing. Further, the through hole 2b (B +) is connected to the support member 3 indicated as “B +”, and the through hole 2b (B−) is connected to the support member 3 indicated as “B−”. In this way, the support member 3 is electrically connected to the multiple layers of piezoelectric ceramics through the through hole 2b.

  FIG. 3 shows the positional relationship between the electrodes of the upper vibrating body 5 and the lower vibrating body 5 when the vibrating body 5 shown in FIG. 2 is arranged to face each other as shown in FIG. In this case, the upper and lower vibrating bodies 5 are rotated 180 ° around the Y axis shown in FIG. 2 and face each other in an inverted state.

  In the positional relationship of FIG. 3, the opposing end portions 3b of the upper and lower support members 3 are electrically connected to each other. That is, the end 3b (A +) of the upper support member 3 and the end 3b (B +) of the lower support member 3 are electrically connected, and the end 3b (B +) of the upper support member 3 and the lower side The end 3b (A +) of the support member 3 is electrically connected. Similarly, the end 3b (A−) of the upper support member 3 and the end 3b (B−) of the lower support member 3 are electrically connected, and the end 3b (B−) of the upper support member 3 is electrically connected. ) And the end 3b (A−) of the lower support member 3 are electrically connected.

  Actually, the opposing end portions 3b (that is, electrodes) of the support member 3 are electrically connected by a conductive member and at the same time mechanically.

  Next, the driving method of the vibration mechanism shown in FIGS. 1 to 3 and the voltage supplied to the vibration body 5 and the vibration mode (shape) of the vibration body 5 will be described. Here, an alternating voltage applied between the electrodes A + and A− in the A region of the piezoelectric ceramic 2 is Va, and an alternating voltage applied between the electrodes B + and B− in the B region is Vb.

  When the AC voltages Va and Vb are set to an AC voltage having a frequency close to the natural frequency of the first vibration mode and the same phase, the entire piezoelectric ceramic 2 (two regions) expands and contracts in the same phase. 5, the vibration of the first vibration mode as shown in FIG. In the first vibration mode, the protrusion 1 a that contacts the contact moving member 4 vibrates in a direction orthogonal to the moving direction of the contact moving member 4, that is, in a contact separation direction that contacts and separates from the contact moving member 4.

  If the AC voltages Va and Vb are AC voltages having a frequency close to the natural frequency of the second vibration mode and a phase shifted by 180 °, the expansion and contraction phases of the A region and the B region of the piezoelectric ceramic 2 are different. Invert. As a result, vibration in the second vibration mode as shown in FIG. In the second vibration mode, the protrusion 1 a that contacts the contact moving member 4 vibrates in the moving direction of the contact moving member 4, that is, the driving direction of the contact moving member 4.

  That is, a combined vector of vectors of AC voltages Va and Vb becomes a voltage vector that generates vibration in the first vibration mode, and a combined vector of vectors of AC voltage Va and -Vb generates a voltage that generates vibration in the second vibration mode. It becomes a vector.

  FIG. 5 shows the relationship between the applied AC voltages Va and Vb and the first and second vibration modes. As shown in FIG. 5, if the applied voltages Va and Vb have the same amplitude (the magnitudes of the vectors Va and Vb), (Va + Vb) and (Va−) regardless of the phase difference θ between Va and Vb. The vectors of Vb) are orthogonal.

  Therefore, if the amplitudes of the applied voltages Va and Vb are made equal and the phase difference θ is changed in the range of −90 ° ≦ θ ≦ 90 °, the vibration locus at the tip of the protrusion 1a changes as shown in FIG. . Note that the numerical values listed in the vertical direction on the left side of FIG. 6 indicate the phase difference θ between the applied voltages Va and Vb. Further, the shapes listed in the second and third columns in the vertical direction in FIG. 6 indicate the vibration trajectories of the tips of the two protrusions 1a corresponding to the phase difference θ listed on the left side of each.

This vibration trajectory is shown as a graph in FIG. In FIG. 7, the horizontal axis represents the phase difference θ between the applied voltages Va and Vb. The vertical axis indicates the vibration amplitude of each protrusion 1a.
With respect to vibration in a direction (contact separation direction) perpendicular to the driving direction (movement direction of the contact moving member 4), the phase difference θ is positive when it is positive and negative when it is negative.

  The characteristics of this vibration trajectory are as follows. That is, the vibration in the contact separation direction perpendicular to the driving direction and the vibration in the driving direction are always orthogonal. Further, the vibration amplitude in the contact separation direction is substantially constant, and the vibration amplitude in the driving direction changes substantially linearly. Further, the vibration in the driving direction reverses from the positive side to the negative side or from the negative side to the positive side from the state where the phase difference θ between Va and Vb becomes zero, and the contact moving member 4 The moving direction of is reversed.

  By bringing the tip of the protrusion 1a into contact with the contact moving member 4 along such a vibration locus, the contact moving member 4 can be moved forward and backward in the direction of the axis. In particular, by making the voltage amplitudes of Va and Vb the same and gradually changing the phase difference θ between Va and Vb, the driving speed of the contact moving member 4 can be smoothly changed from forward to backward.

  Next, the relationship between the vibrations of the upper and lower vibrating bodies 5 when the vibrating bodies 5 that generate vibrations as described above are arranged as shown in FIG. 3 will be described.

  As described above, the upper electrode 3b (A +) and the lower electrode 3b (B +) are electrically connected to each other, and the upper electrode 3b (B +) and the lower electrode 3b (A +) are electrically connected. Similarly, the upper electrode 3b (A−) and the lower electrode 3b (B−) are electrically connected, and the upper electrode 3b (B−) and the lower electrode 3b (A−) are electrically connected.

  Here, a portion where the upper electrode 3b (A +) and the lower electrode 3b (B +) are connected is referred to as an A1 terminal again. Similarly, the portion where the upper electrode 3b (B +) and the lower electrode 3b (A +) are connected is the B1 terminal, and the upper electrode 3b (A−) and the lower electrode 3b (B−) are connected. The part will be referred to as the A2 terminal again. Further, a portion where the upper electrode 3b (B-) and the lower electrode 3b (A-) are connected is referred to as a B2 terminal again.

  An AC voltage Va is applied between the A1 terminal and the A2 terminal, and an AC voltage Vb is applied between the B1 terminal and the B2 terminal. When the phase difference θ is changed within the range of −90 ° ≦ θ ≦ 90 ° with equal voltage amplitude, Va and Vb generate vibrations in the first vibration mode and the second vibration mode as shown in FIG. .

  At this time, since the same potential is applied to the electrodes having the same polarization polarity, the same vibration displacement occurs in the polarization regions where the upper vibrating body 5 and the lower vibrating body 5 face each other. Further, since the upper and lower vibrating bodies 5 are opposed to each other in a state where one of them is rotated 180 ° around the Y axis and turned upside down, as shown in FIG. The vibration displacement is mirror-symmetric with respect to the contact moving member 4.

  Further, as shown in FIG. 9, the upper and lower protrusions 1 a that are in contact with the contact moving member 4 are also in a positional relationship facing from both sides of the contact moving member 4. Therefore, regarding the contact force in the contact separation direction (vertical direction in FIG. 9), the upper and lower protrusions 1a apply the same force in the opposite direction to the contact moving member 4 at the same timing. For this reason, bending vibration stress is not applied to the contact moving member 4, and bending vibration is not generated, and the contact moving member 4 can be smoothly moved in a certain direction.

  Further, although the support member 3 is also displaced in mirror symmetry, the ends 3b of the support members 3 of the upper and lower vibrating bodies 5 are not only electrically connected but also mechanically connected. For this reason, the vibrations transmitted to the end portions 3b of the upper and lower support members 3 cancel each other. Therefore, the vibration displacement at the end portion (electrode 3b) becomes almost zero, and the end portion (electrode 3b) becomes almost stationary. If the end 3b of the substantially stationary support member 3 is fixed to another member, vibration propagation to the other member can be suppressed almost completely. In other words, it is possible to suppress the generation of vibration noise due to the propagation of vibration from the end 3b of the support member 3 to the surroundings.

  As is clear from the above description, since an in-phase AC voltage may be applied to the end portions 3b of the support members 3 facing each other of the two vibrating bodies 5, the peripheral wiring circuit can be simplified. . Note that the end portions 3b of the support members 3 of the upper and lower vibrating bodies 5 are not only directly connected in practice, but may be indirectly connected via other members as shown in FIG. good.

  FIG. 10 shows a configuration when a linear vibration driving device is used for driving a lens.

  In FIG. 10, the round bar-shaped contact moving member 4 is fitted to the lens guide 6 with a minute clearance. A lens frame 7 is integrally attached to the lens guide 6, and the lens guide 6 guides a moving direction of a lens (not shown) attached to the lens frame 7. A groove portion is formed at the position of the lens frame 7 opposite to the mounting position of the lens guide 6, and a round bar-shaped rotation stopper 8 is fitted in the groove portion.

  The two vibrating bodies 5 are fixed to the lens guide 6 by a conductive screw 9 through a hole 3 c formed in the end 3 b of the support member 3. Thereby, the elastic body 1 (strictly, the protruding portion 1a) of the upper and lower vibrating bodies 5 is pressed against the contact moving member 4 passing through the fitting hole of the lens guide 6. Furthermore, the end portions 3b of the supporting members 3 facing the upper and lower vibrating bodies 5 are electrically and mechanically connected.

  Accordingly, the mirror-symmetric vibrations transmitted to the end portions 3b of the upper and lower support members 3 act on the lens guide 6 in such a manner that they cancel each other. For this reason, even if there is a clearance between the lens guide 6 and the contact moving member 4, vibration of the lens guide 6 and generation of vibration noise can be suppressed.

  Moreover, the flexible printed circuit board etc. which were conventionally required separately by electrically and mechanically connecting the edge parts 3b of the supporting member 3 which the upper and lower vibrating bodies 5 oppose with the electroconductive screw | thread 9 etc. This wiring member becomes unnecessary.

  In addition, since the vibration of the lens guide 6 can be suppressed as described above, the rigidity of the lens guide 6 may not be so high. Therefore, the thickness of the lens guide 6 in the contact separation direction may be reduced to a thin plate shape. In this case, although it contributes to size reduction and cost reduction, if the contact moving member 4 is also made into a thin plate at the same time, it becomes possible to achieve further size reduction and cost reduction.

  Furthermore, instead of the screw 9 in FIG. 10, it is also possible to use a conductive bar material in which at least a portion inserted into the hole 6c of the lens guide 6 is not a screw portion. In this case, with the upper and lower vibrating bodies 5 placed directly on the lens guide 6, the hole 3 c formed in the end 3 b of the upper and lower support members 3 and the hole 6 c of the lens guide 6 are aligned. In this state, the upper and lower holes 3c and the rod 6c of the lens guide 6 are passed through. Then, at the upper and lower holes 3c or in the vicinity thereof, the end 3b of the support member 3 is fixed to the bar.

  When the end portions 3b of the support members 3 of the upper and lower vibrating bodies 5 are mechanically joined in such a form, vibrations transmitted to the end portions 3b of the upper and lower support members 3 cancel each other, and the lens The vibration of the guide 6 and the generation of vibration noise can be further suppressed.

  When the bar is used as described above, a washer-shaped member made of an elastic body is attached to the bar, and the washer-shaped member is interposed between the end 3 b of the support member 3 and the lens guide 6. It is desirable to intervene. By doing in this way, even if the end part 3b of the joined support member 3 vibrates, the vibration can be absorbed by the washer-like member made of an elastic body.

  In the above example, the phase difference θ between Va and Vb is changed in a range of −90 ° ≦ θ ≦ 90 °, but the initial phase difference θ between Va and Vb is −90 ° or less, or + 90 ° or more. Even if it is changed within the range of 180 °, the same effect can be obtained. In this case, the vibration in the direction (contact separation direction) perpendicular to the driving direction decreases with the vibration amplitude, but drive control is possible.

  Further, the extending portion 3 a of the support member 3 may be configured to extend toward the center portion of the vibrating body 5 as illustrated in FIG. 11. Further, as shown in FIG. 12, the extending portion 3 a of the support member 3 may be configured to extend only in one direction of the advancing direction or the retreating direction of the contact moving member 4. .

  11 and 12, if one vibrating body 5 is rotated by 180 ° around the Y axis and the two vibrating bodies 5 are opposed to each other in an inverted state, the polarities of the electrodes 3 b facing each other are reversed. The relationship is exactly the same as in the case of FIG. Therefore, when the vibrating body 5 of FIGS. 11 and 12 is used, the electrodes 3b facing each other are electrically and mechanically connected, and a voltage is applied in the form as described above.

  Thereby, the vibration displacement of the two vibrating bodies 5 facing each other is mirror-symmetric with respect to the contact moving member 4. In this case, the vibrations transmitted from the two opposing vibrating bodies 5 to the end portion (electrode 3b) of the support member 3 cancel each other. Accordingly, the vibration displacement at the end portion (electrode 3b) becomes zero and the end portion (electrode 3b) becomes almost stationary, so that vibration propagates from the end portion (electrode 3b) to the surroundings to generate vibration sound. Can be prevented.

  In the vibrating body 5 shown in FIG. 13, the polarity on the B side of the end portion (electrode) 3 b of the support member 3 is reverse to that in the case of FIG. 2.

  In this case, even if one vibrating body 5 is rotated 180 ° around the Y axis so that the two vibrating bodies 5 face each other in an inverted state and the opposing electrodes 3b are electrically connected, they have different polarities. The electrodes are connected. In other words, even if a voltage is applied in the form as described above, the vibration displacement of the two vibrating bodies 5 facing each other is not mirror-symmetric with respect to the contact moving member 4, and the above effect cannot be obtained.

  Therefore, when using the vibrating body 5 shown in FIG. 13, in order to acquire said effect, the electrodes 3b are electrically connected with the following forms. That is, the electrodes 3b of the opposing support member 3 are electrically separated and separated from the upper electrode 3b (A +), the lower electrode 3b (B +), and the upper electrode 3b (B +) by separate wiring. The lower electrode 3b (A +) is electrically connected. Similarly, the upper electrode 3b (A-) and the lower electrode 3b (B-), and the upper electrode 3b (B-) and the lower electrode 3b (A-) are electrically connected by separate wiring. To do.

  Further, even when the vibrating body 5 shown in FIG. 13 is used, the opposing electrodes 3b are mechanically connected to each other. Thereby, by applying a voltage in the form as described above, the vibration displacement of the vibrating body 5 and the support member 3 becomes mirror-symmetrical, and the above-described effect is obtained.

  The support member 3 of the vibrating body 5 can also be configured as shown in FIG. When the vibrating body 5 of FIG. 14 is used, one of the vibrating bodies 5 is rotated by 180 ° around the X axis so that the two vibrating bodies 5 face each other in an inverted state. In this case, the upper and lower electrodes 3b are opposed to each other in the form of (A +) and (A +), (A−) and (A−), (B +) and (B +), and (B−) and (B−). Thus, the regions (A region, B region) of the facing electrode 3b are different from those in FIGS. However, the two opposing electrodes 3b have the same polarity.

  Therefore, when the vibrating body 5 shown in FIG. 14 is used, the opposing electrodes 3b are electrically and mechanically connected. Then, Va and Vb are applied to the terminals related to the connection of the electrodes 3b in the A region and the B region, respectively, in the above-described manner. Thereby, the same effect as the case of FIG.

[Second Embodiment]
Although the vibrating body according to the first embodiment is a linear drive type vibrating body, the rotational driving type vibrating body also includes two support members for the vibrating body as in the first embodiment. It is also possible to configure the vibration displacement of the end portion to be mirror-symmetric with respect to the contact moving member.

  FIG. 15 is an exploded perspective view illustrating a rotational drive type vibration mechanism of the vibration drive device according to the second embodiment of the invention.

  As shown in FIG. 15, in this vibration mechanism, two vibrating bodies 50 having the same structure are arranged to face each other with the contact moving part 40 interposed therebetween. The contact moving member 40 has a disk shape. A shaft 60 is passed through the central portion of the contact moving member 40 in a fixed state.

The vibrating body 50 includes a hollow disk-shaped elastic body 10 and a piezoelectric ceramic 20 that are bonded to each other. The two vibrating bodies 50 are arranged so that the elastic body 10 is positioned on the contact moving body 40 side. A protrusion 10 a is formed on the outer surface of the elastic body 10, that is, the surface facing the contact moving member 40. The vibrating body 50 contacts the contact moving member 40 via the protrusion 10 a and transmits the vibration to the contact moving member 40 to rotate the contact moving member 40. The rotational force of the contact member 40 is transmitted to another member (not shown) via the shaft 60.

  The piezoelectric ceramic 20 is a kind of electro-mechanical energy conversion element, and a thin plate-like support member 30 is attached to the outer surface thereof. The support member 30 is formed of a conductive spring member, and has a substantially L-shaped extending portion 30a extending from a region of the piezoelectric ceramic 20 integrated with the elastic body 10 by bonding. . A hole 30c is formed in the end 30b of the extension 30a. The hole 30c is formed in order to attach the support member 30 having a spring property to some other member and bring the vibrating body 50 into contact with the contact moving body 40 in a separable form.

  The support member 30 also has a power feeding function that excites mechanical vibration by supplying voltage to the piezoelectric ceramic 20. That is, the support member 30 supplies a support function for supporting the vibrating body 50, a spring function for bringing the vibrating body 50 into contact with the contact moving member 40 in a separable form, and electrical energy for obtaining mechanical vibration. It also has a power feeding function. Therefore, a pressure member, a power supply wiring, and the like that are separately required in the past are unnecessary, and it is possible to reduce the size and weight.

  FIG. 16 shows the relationship between the support member 30 as a power supply member and the polarization polarity of the electrodes of the piezoelectric ceramic 2 connected thereto.

  The piezoelectric ceramic 20 has an electrode region divided into six in the rotation direction of the contact moving member 40. These six electrode regions are alternately classified into an A region and a B region as indicated by “A +”, “A−”, “B +”, and “B−” in FIG. The same voltage is applied to the three A regions. Similarly, the same voltage is applied to the three B regions. Note that the protrusions 10a shown in FIG. 15 are formed at three positions at a pitch of 120 ° at positions on the elastic body 10 corresponding to the boundary positions between the A region and the B region.

  The piezoelectric ceramic 20 includes a plurality of layers of piezoelectric ceramics and electrodes. The broken line shown in FIG. 16 is the internal electrode 20a, and the internal electrode 20a is divided into the A region and the B region as described above. The twelve black dots in FIG. 16 indicate the end faces of the through holes that communicate with the internal electrode 20a.

  The through hole 20b (A +) is connected to an electrode having a positive polarization polarity in the A region. The through hole 20b (A−) is connected to an electrode having a negative polarization polarity in the A region. The through hole 20b (B +) is connected to an electrode having a positive polarization polarity in the B region. The through hole 20b (B−) is connected to an electrode having a negative polarization polarity in the B region. The individual display of the positive and negative electrodes in these internal electrodes 20a is not shown.

  The support member 30 is bonded to the outer peripheral portion of the outer surface of the piezoelectric ceramic 20 with an adhesive or the like, and is electrically connected to the end face of the through hole with a conductive paint (not shown). Specifically, the through hole 20b (A +) is connected to the support member 30 labeled “A +”, and the through hole 20b (A−) is connected to the support member 30 labeled “A−”. ing. The through hole 20b (B +) is connected to the support member 30 labeled “B +”, and the through hole 20b (B−) is connected to the support member 30 labeled “B−”. As described above, the support member 30 is electrically connected to the multi-layered piezoelectric ceramics 20 through the through hole 20b.

  The piezoelectric ceramic 20 is divided into six regions, and each of these regions has a positive electrode and a negative electrode (internal electrode), and therefore has a total of 12 internal electrodes. On the other hand, the number of the support members 30 and the extending portions 30a is “6”. Thus, the support structure and the power supply wiring structure can be simplified by reducing the number of the support members 30 and the extending portions 30a from the total number of internal electrodes related to the positive and negative polarizations of the piezoelectric ceramic 20. In addition, the vibration drive device can be reduced in size and price.

  FIG. 17 shows the positional relationship between the electrodes of the left vibrating body 50 and the right vibrating body 50 when the vibrating bodies 50 having the polarities of the electrodes shown in FIG. 16 are arranged facing each other as shown in FIG. Yes. In this case, one of the left and right vibrating bodies 50 is rotated 180 ° around the Y axis shown in FIG.

  In the positional relationship of FIG. 17, the end portions 30 b of the left and right support members 30 are electrically connected to each other. That is, the end 30b (A +) of the left support member 30 and the end 30b (B +) of the right support member 30 are electrically connected, and the end 30b (B +) of the left support member 30 and the right support The end 30b (A +) of the member 30 is electrically connected. Similarly, the end 30b (A−) of the left support member 30 and the end 30b (B−) of the right support member 30 are electrically connected, and the end 30b (B−) of the left support member 30 is connected. And the end 30b (A-) of the right support member 30 are electrically connected.

  In practice, the opposing end portions 30b (that is, electrodes) of the support member 30 are electrically connected and mechanically connected by the conductive member.

  Next, the driving method of the vibration mechanism shown in FIGS. 15 to 17 and the voltage supplied to the vibration body 50 and the vibration mode (shape) of the vibration body 50 will be described. Here, as in the first embodiment, an alternating voltage applied between the electrodes A + and A− in the A region of the piezoelectric ceramic 20 is applied between Va and the electrodes B + and B− in the B region. Let ACb be Vb.

  When the AC voltages Va and Vb are set to an AC voltage having a frequency close to the natural frequency of the first vibration mode and the same phase, the entire piezoelectric ceramic 20 (six regions) expands and contracts in the same phase. 50, vibration in the first vibration mode is generated.

  In this first vibration mode, as shown in FIG. 18, the vicinity of the inner diameter of the hollow disk-shaped elastic body 10 is recessed (the vicinity of the outer diameter protrudes), and conversely, the vicinity of the outer diameter is recessed after 1/2 cycle. Piezoelectric ceramics 20 vibrate in a form (protrusions near the inner diameter). Due to the vibration in the first vibration mode, the tip of the protrusion 10 a of the elastic body 10 contacts or separates from the contact moving member 40.

  If the AC voltages Va and Vb are AC voltages having a frequency close to the natural frequency of the second vibration mode and a phase shifted by 180 °, the expansion and contraction phases of the A region and the B region of the piezoelectric ceramic 20 are different. Invert. As a result, the vibration of the second vibration mode as shown in FIG. 19 is generated in the piezoelectric ceramic 20, that is, the elastic body 10 of the vibrating body 50. In this second vibration mode, the hollow disc-shaped elastic body 50 has three peaks and three valleys in the circumferential direction, and after 1/2 cycle, the peaks change into valleys and the valleys change into peaks. The ceramic 20 vibrates. Due to the vibration in the second vibration mode, the tip of the protrusion 10a of the elastic body 10 reciprocates in the circumferential direction.

  The contact moving member 40 is rotated by a combination of contact / separation vibration in the first vibration mode and circumferential vibration in the second vibration mode. In this case, smooth drive control without a dead zone is also realized in the rotary vibration drive mechanism.

  The vector relationship between the AC voltages Va and Vb for rotating the contact moving member 40, the control of the phase difference θ, and the like are as described in the first embodiment with reference to FIGS. Then, the detailed explanation is omitted.

  Next, the relationship between the vibrations of the left and right vibrating bodies 50 when the vibrating body 5 that generates vibration as described above is arranged as shown in FIG. 17 will be described.

  As described above, the left electrode 30b (A +) and the right electrode 30b (B +), and the left electrode 30b (B +) and the right electrode 30b (A +) are electrically connected. Similarly, the left electrode 30b (A-) and the right electrode 30b (B-), and the left electrode 30b (B-) and the right electrode 30b (A-) are electrically connected.

  Here, a portion where the left electrode 30b (A +) and the right electrode 30b (B +) are connected is referred to as an A1 terminal again. Similarly, the portion where the left electrode 30b (B +) and the right electrode 30b (A +) are connected is the B1 terminal, and the portion where the left electrode 30b (A−) and the right electrode 30b (B−) are connected. It will be referred to as the A2 terminal again. Further, a portion where the left electrode 30b (B-) and the right electrode 30b (A-) are connected is referred to as a B2 terminal again.

  An AC voltage Va is applied between the A1 terminal and the A2 terminal, and an AC voltage Vb is applied between the B1 terminal and the B2 terminal. Va and Vb have the same voltage amplitude and the phase difference θ is changed in the range of −90 ° ≦ θ ≦ 90 °, the first vibration mode shown in FIG. 18 and the second vibration mode shown in FIG. Generates vibration.

  In this case, the left and right vibrating bodies 50 face each other in a state where one side is rotated by 180 ° around the Y-axis and the front and back sides are reversed. A potential is applied. Therefore, the same vibration displacement occurs in the area where the left vibrating body 50 faces, and the vibration displacement of the left and right vibrating bodies 50 is mirror-symmetric with respect to the contact moving member 40.

  Further, the left and right protrusions 10a that come into contact with the contact moving member 40 are also positioned so as to face each other from both sides of the contact moving member 40 (see FIGS. 15 and 17). Therefore, regarding the contact force in the contact separation direction (left and right direction in FIGS. 15 and 17), the left and right protrusions 10a apply the same force in the opposite direction to the contact moving member 40 at the same timing. For this reason, bending vibration stress is not applied to the contact moving member 40, and bending vibration does not occur.

  Furthermore, although the support member 30 is also displaced mirror-symmetrically, the end portions 30b of the support members 30 of the left and right vibrating bodies 50 are not only electrically connected but also mechanically connected. For this reason, the vibrations transmitted to the end portions 30b of the left and right support members 30 cancel each other. Therefore, the vibration displacement at the end portion 30b (electrode) becomes substantially zero, and the end portion 30b (electrode) becomes substantially stationary. If the end 30b of the substantially stationary support member 30 is fixed to another member, vibrations of the other member can be suppressed almost completely. In other words, it is possible to suppress the generation of vibration noise due to the propagation of vibration from the end 3b of the support member 3 to the surroundings.

  As is clear from the above description, since the in-phase AC voltage may be applied to the end portions 30b of the support members 30 facing each other of the two vibrating bodies 50, the peripheral wiring circuit can be simplified. . Note that the end portions 30b of the support members 30 of the left and right vibrating bodies 50 are not only directly joined by solder or the like, but also connected by using other members as shown in FIG. Also good.

  FIG. 20 is a diagram showing a mounting form in the case where a rotational drive type vibration mechanism is mounted on the apparatus. In FIG. 20, the left and right vibrating bodies 50 are surrounded by left and right cases 110 and fixed with screws 100. Specifically, the left and right vibrating bodies are formed by screwing the screws 100 into the holes 30c formed in the end portions 30b of the support members 30 of the left and right vibrating bodies 50 and the screw holes 110a formed in the left and right cases 110. 50 is housed in the left and right cases 110.

  In this case, the shaft 60 attached to the contact moving member 40 on the disk is pivotally supported by a bearing 110 a provided at the center of the left and right cases 110. As apparent from FIG. 20, when the elastic bodies 10 are brought into contact with the contact moving member 40 between the support members 30 of the left and right vibrating bodies 50, the left and right elastic bodies 10 and the piezoelectric ceramics 20. A gap corresponding to the thickness of is formed. Accordingly, due to the elasticity of the support members 30 of the left and right vibrating bodies 50, the left and right vibrating bodies 50, strictly speaking, the elastic bodies 10 are pressed against the contact moving member 40. This pressure contact force can be adjusted by inserting the spacer 120 between the end portions 30 b of the left and right support members 30.

  Furthermore, since the screw 100 is formed of a conductive member, the end portions 30b of the support members 30 facing the left and right vibrating bodies 50 are not only electrically connected but also mechanically joined. The Therefore, the mirror-symmetric vibrations transmitted to the end portions 30b of the left and right support members 30 cancel each other, and the vibrations at the end portions 30b of the left and right support members 30 and the generation of vibration noise are suppressed. Can do.

  In addition, by electrically and mechanically connecting the end portions 30b of the support members 30 of the upper and lower vibrating bodies 50 with the conductive screws 100, wiring members such as flexible printed boards that have been conventionally required can be obtained. It becomes unnecessary.

  The relationship between the support member 30 as a power supply member and the polarization polarity of the electrode of the piezoelectric ceramic 20 connected to the support member 30 can be configured as shown in FIG. In the configuration of FIG. 21, the lower four negative poles shown in FIG. 16 are short-circuited to form a common electrode G for one ground line. Further, the upper right “A +” pole in FIG. 16 corresponds to the lower left “A +” pole in the configuration of FIG. Further, the “B +” pole at the upper left of FIG. 16 corresponds to the “B +” pole at the lower right in the configuration of FIG.

  When two vibrating bodies 50 configured as shown in FIG. 21 are used, one of the vibrating bodies is rotated 180 ° to face each other in an inverted state, and the end portions 30b of the opposing support members 30 are electrically connected to each other. Connect mechanically. In this case, assuming that the vibrating body 50 in the state of FIG. 21 corresponds to the left vibrating body 50 of FIG. 17, the lower left “A +” pole of FIG. 21 and the “B +” pole connected thereto are described above. Corresponds to the A1 terminal. Further, the “B +” pole in the lower right of FIG. 21 and the “A +” pole connected to it correspond to the aforementioned B1 terminal.

  Therefore, when driving, the AC voltage Va is applied to the A1 terminal and the AC voltage Vb is applied to the B1 terminal in a state where the terminal related to the common electrode G is connected to the ground line. At this time, the voltage amplitudes of the AC voltages Va and Vb are made the same, and the phase difference θ is changed in the range of −90 ° ≦ θ ≦ 90 °, whereby the first vibration mode shown in FIG. The vibration of the second vibration mode shown in FIG. In this case, the same effect as in the case of FIG. 17 can be obtained.

  In the case of the vibrating body 50 shown in FIG. 21, the number of supporting members 30 and extending portions 30a as electrodes is only three, and there are two electrodes related to substantial drive control excluding the electrodes related to the ground. Only. Accordingly, it is possible to achieve results such as simplification of the drive control circuit (not shown), reduction in size of the vibration drive device, and price reduction, compared with the vibrating body 50 of FIG.

  The relationship between the support member 30 as a power supply member and the polarization polarity of the electrode of the piezoelectric ceramic 20 connected to the support member 30 can also be configured as shown in FIG. In the configuration of FIG. 22, two support members 30 are provided corresponding to each polarization region of the piezoelectric ceramic 20.

  Even when two vibrating bodies 50 configured as shown in FIG. 22 are used, one of the vibrating bodies is rotated 180 ° to face each other in an inverted state, and the end portions 30b of the opposing support members 30 are electrically connected to each other. Connect mechanically. In this case, assuming that the vibrating body 50 in the state of FIG. 22 corresponds to the vibrating body 50 on the left side of FIG. 17, the A1, A2, B1, and B2 terminals are as shown in FIG. Become.

  Therefore, when driving, the AC voltage Va and the AC voltage Vb are applied to the A1, A2, B1, and B2 terminals in exactly the same manner as in FIG. The effect of can be obtained.

  In addition, this invention is not limited to said embodiment, A various application deformation | transformation is possible. For example, in the second embodiment, the piezoelectric ceramic 20 is divided into six regions, the second vibration mode is set to a mode in which three peaks and valleys are formed, and the three protrusions 10a that are in contact with the contact moving member 40 are formed. Formed.

  However, the number of peaks, valleys, and protrusions 10a can be arbitrarily changed as long as Formula 1 is satisfied.

[Equation 1]
m = n = P / 2
However, P: Number of regions related to division, m: Number of peaks (number of valleys), n = number of protrusions For example, the piezoelectric ceramic 20 is divided into eight regions, and the second vibration mode is divided into four A mode in which peaks and valleys are formed may be used, and the number of protrusions 10a that are in contact with the contact moving member 40 may be “4”.

  Further, the extending portion of the support member does not need to have the three functions of the support function, the spring function, and the power feeding function, and may have only two of these functions.

  Furthermore, the electro-mechanical energy conversion element does not need to be a laminated type or made of ceramics, and other types of electro-mechanical energy conversion elements can be used as long as the functions according to the above embodiments are performed. It is.

It is a disassembled perspective view which shows the structure of the vibration mechanism of the linear drive type vibration drive device which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating the correspondence of the electrode of the support member of the vibration mechanism shown in FIG. 1, and piezoelectric ceramics. It is a figure for demonstrating the positional relationship of the electrode of these vibrating bodies, etc. when two vibrating bodies are arrange | positioned facing. It is a schematic diagram which shows the vibration which concerns on two vibration modes excited by the said vibrating body. It is a figure for demonstrating the relationship between the electric power applied to the said vibrating body, and said two vibration mode. It is a figure which shows the vibration locus | trajectory of the front-end | tip of the projection part formed in the said vibrating body. It is a figure which shows the relationship between the phase difference of the alternating voltage applied to the piezoelectric ceramic of the said vibrating body, and the amplitude of the vibration of each direction excited by the piezoelectric ceramic. It is a schematic diagram which shows the relationship of the vibration excited by the said 2 vibrating body. It is a figure for demonstrating the positional relationship of the projection part formed in the said 2 vibrating body. It is a perspective view which shows the structure at the time of using the linear drive type vibration mechanism shown in FIG. 1 etc. for lens drive, such as a camera. It is a figure which shows the modification of the supporting member of the vibration mechanism of a linear drive type vibration drive device. It is a figure which shows the other modification of the supporting member of the vibration mechanism of a linear drive type vibration drive device. It is a figure which shows the other modification of the supporting member of the vibration mechanism of a linear drive type vibration drive device. It is a figure which shows the other modification of the supporting member of the vibration mechanism of a linear drive type vibration drive device. It is a disassembled perspective view which shows the structure of the vibration mechanism of the rotational drive type vibration drive device which concerns on the 2nd Embodiment of this invention. FIG. 16 is a diagram for explaining a correspondence relationship between a support member of the rotational drive type vibration mechanism shown in FIG. 15 and electrodes of piezoelectric ceramics. It is a figure for demonstrating the positional relationship of the electrode of these vibrating bodies, etc. when two vibrating bodies are arrange | positioned facing (2nd Embodiment). It is a schematic diagram which shows the vibration which concerns on the 1st vibration mode excited by the said vibrating body (2nd Embodiment). It is a schematic diagram which shows the vibration which concerns on the 2nd vibration mode excited by the said vibrating body. FIG. 16 is a perspective view showing a mounting form when the rotational drive type vibration mechanism shown in FIG. It is a figure which shows the modification of the supporting member of the vibration mechanism of a rotational drive type vibration drive device. It is a figure which shows the other modification of the supporting member of the vibration mechanism of a rotational drive type vibration drive device.

Explanation of symbols

2,20 ... Piezoelectric ceramics (electro-mechanical energy conversion element)
2a, 20a ... internal electrodes 2b, 20b ... through hole end portions 3, 30 ... support members 3a, 30a ... support member extension portions 4, 40 ... contact moving members 5, 50 ... vibrating bodies 10, 100 ... screws

Claims (9)

In a vibration driving device that arranges two vibrating bodies facing each other via a contact moving member, and vibrates the two vibrating bodies by supplying power to apply a driving force to the contact moving member.
The two vibrating bodies are support members for supporting the vibrating body by attaching it to another member, and an extending portion extending from a region of the electro-mechanical energy conversion element constituting the vibrating body is provided. The extension member is formed and supplies power to the electro-mechanical energy conversion element, and is electrically and mechanically connected to the extension part of the other opposite support member. Have
Wherein the power supply to the extended portion of the two vibrator, Ri Do mirror-symmetrical vibration displacement of the two vibrators to the contact moving member,
The electro-mechanical energy conversion element is divided into a plurality of regions to which positive and negative polarization polarities are respectively applied, and the support member and the extending portion are configured to have electric power related to the positive and negative polarization polarities of the plurality of regions. vibration driving apparatus characterized that you have provided a plurality of such may supply.   The vibration drive device according to claim 1, wherein the extending portion of the support member is configured by a spring member.   The vibration drive device according to claim 2, wherein the extending portion of the support member is formed of a conductive spring member. The number of the plurality of support members and the extending portion, the electrical - vibration drive according to claim 1, characterized in that the small number than the total number of inner electrodes in accordance with positive and negative polarization polarity of mechanical energy conversion element apparatus. 2. The vibration drive device according to claim 1 , wherein the plurality of support members and the extending portions are provided at positions that are symmetrical with respect to a predetermined straight line passing through a center of the vibrating body. The extending portions of the plurality of support members include a first vibration that causes the vibrating body to vibrate in a direction opposite to the contact moving member, and a predetermined direction of the contact moving member that is perpendicular to the opposite direction. vibration driving apparatus according to claim 1, wherein said that the power supply is performed to excite a second vibration that vibrates in the driving direction of. The plurality of support members and the extension portions are divided into two groups based on the plurality of regions of the electro-mechanical energy conversion element and the positive and negative polarization polarities, and the extension portions of the two groups include 2. The vibration drive device according to claim 1 , wherein AC voltages having the same voltage amplitude and being out of phase with each other are applied.   The vibration driving apparatus according to claim 1, wherein the vibrating body has a rectangular plate shape and generates vibration for linearly driving the contact moving member by the power supply. The vibration driving apparatus according to claim 1, wherein the vibrating body is in a hollow disk shape and generates vibration for rotationally driving the contact moving member by the power supply.

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