JP2018099002A - Vibration type actuator, lens barrel having the same, imaging apparatus, and stage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibration type actuator capable of reducing deterioration of actuation even when abrasion of a driven body is progressed.SOLUTION: A vibration type actuator 1 comprises: a driven body 3 having a permanent magnet 5; and a vibrator 2 having an elastic body 2b having magnetism and an electric-mechanical energy conversion element 2a bonded to the elastic body. By applying a driving voltage to the electric-mechanical energy conversion element, a vibration is excited to the vibrator, and the driven body and the vibrator are relatively moved in a movement range to a relative movement direction by the vibration. In a state where the driven body is moved up to an end part of one side of the relative movement direction of the movement range, the end part of the other side of the relative movement direction of the permanent magnet is arranged on one direction from the end part of the other side of the elastic body.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vibration type actuator, a lens barrel having the vibration type actuator, an imaging apparatus, and a stage apparatus.

  2. Description of the Related Art A vibration type actuator is known in which a vibrating body and a driven body are brought into pressure contact with each other, and the vibrating body and the driven body are relatively moved by vibration excited by the vibrating body. Such a vibration type actuator is described in Patent Document 1.

  FIG. 15 is a schematic diagram illustrating the configuration of a known vibration type actuator 100. The vibration type actuator 100 includes a vibration body 102 and a driven body 103. The vibrating body 102 is bonded to the elastic body 102b, the two protrusions 102d provided on one surface of the elastic body 102b, and the surface of the elastic body 102b opposite to the surface on which the protrusion 102d is provided. And a piezoelectric element 102a. The two protrusions 102d are arranged at a predetermined interval in the X direction in FIG. 15, and the tip surfaces (upper surfaces) are in pressure contact with the driven body 103. The elastic body 102b and the two protrusions 102d include, for example, a metal member such as stainless steel. The piezoelectric element 102a is bonded to the elastic body 102b with an adhesive, for example.

  By applying a two-phase AC voltage having a phase difference from a drive circuit (not shown) to the piezoelectric element 102a, vibrations in two bending vibration modes are excited in the vibrating body 102. Then, by combining the excited vibrations of the two bending vibration modes, an elliptical motion in the ZX plane is generated at the tip of the protrusion 102d. At this time, since the tips of the two protrusions 102d are in pressure contact with the driven body 103, the driven body 103 receives a frictional driving force due to the elliptical motion of the two protrusions 102d. Thereby, the vibrating body 102 and the driven body 103 can be relatively moved in the X direction.

  Patent Document 2 describes a vibration type actuator that rotationally drives a driven body using a plurality of vibrating bodies 102. In Patent Document 2, three vibrating bodies 102 are arranged at equal intervals on the same circumference so that lines connecting the two protrusions 102d of the respective vibrating bodies 102 coincide with tangent lines of the circumference. Thereby, the disk-shaped or annular driven body that is in pressure contact with the two vibrating bodies 102 can be rotated.

JP 2004-320846 A JP 2012-5309 A

  However, in the vibration type actuator 100, when the reciprocating motion is repeated in the X direction within the predetermined moving range, the wear amount is at both ends of the moving range which is the operation start position and the operation end position of the driven member 103. There was an increase. This is because both the ends of the predetermined movement range of the driven body 103 start and stop the vibration type actuator 100, so that the generated acceleration is the largest and the relative speed difference between the driven body 103 and the protrusion 102d is large. . For this reason, the wear tends to proceed as compared with other positions of the driven body 103. As a result, the startability may be reduced at both ends of the moving range of the vibration type actuator 100.

  Also, in the rotary vibration actuator described in Patent Document 2, if the reciprocating motion is repeated within a predetermined movement range where the rotation angle of the driven body is less than 360 degrees, both ends of the movement range of the driven body will be described. There was a risk that the amount of wear increased at the part, and the start-up performance was lowered.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a vibration type actuator that can reduce a decrease in startability as compared with the conventional art even when wear of a driven body advances.

  A vibration type actuator according to one aspect of the present invention includes a driven body having a permanent magnet, an elastic body having magnetism, and a vibration body having an electro-mechanical energy conversion element joined to the elastic body. By applying a driving voltage to the electro-mechanical energy conversion element, vibration is excited in the vibrating body, and the driven body and the vibrating body are relatively moved within a moving range in a relative movement direction by the vibration. In the vibration type actuator, in the state where the driven body is moved to one end portion in the relative movement direction of the movement range, the other end portion in the relative movement direction of the permanent magnet is: The elastic member is disposed on the one side with respect to the other end portion of the elastic body.

  According to the vibration type actuator as one aspect of the present invention, even if the driven body is more worn, it is possible to reduce the decrease in the startability as compared with the related art.

The schematic diagram explaining the structure of the vibration type actuator which concerns on 1st Embodiment. The schematic diagram explaining the magnetic circuit formed of the permanent magnet of the vibration type actuator which concerns on 1st Embodiment. The perspective view explaining the deformation | transformation of the vibrating body in the 1st vibration mode excited by the vibrating body of the vibration type actuator which concerns on 1st Embodiment. The perspective view explaining the deformation | transformation of the vibrating body in the 2nd vibration mode excited by the vibrating body of the vibration type actuator which concerns on 1st Embodiment. The schematic diagram explaining the structure of the electrode of the piezoelectric element of the vibration type actuator which concerns on 1st Embodiment. The schematic diagram explaining the moving range of the to-be-driven body of the vibration type actuator which concerns on 1st Embodiment. The figure explaining the relationship between the position of the to-be-driven body and attraction | suction force of the vibration type actuator which concerns on 1st Embodiment. The figure explaining the elliptical motion of the vibrating body of the vibration type actuator which concerns on 1st Embodiment. The figure explaining the change of the position of the to-be-driven body of the vibration type actuator which concerns on 1st Embodiment, and the attraction force difference of the right and left of an elastic body. The perspective view explaining the structure of the vibration type actuator which concerns on a 1st modification. The perspective view explaining the structure of the vibration type actuator which concerns on 2nd Embodiment. The perspective view explaining the moving range of the to-be-driven body of the vibration type actuator which concerns on 2nd Embodiment. FIG. 2 is a schematic diagram illustrating a configuration of an imaging apparatus using the vibration type actuator according to the first embodiment. 1 is an external perspective view of a microscope having a stage device using the vibration type actuator of the first embodiment. The schematic diagram explaining the structure of the conventional vibration type actuator.

(First embodiment)
A vibration type actuator 1 according to this embodiment will be described with reference to FIG. FIG. 1A is a schematic diagram illustrating the configuration of the vibration type actuator 1. The vibration type actuator 1 includes a vibration body 2 and a driven body 3 that is in pressure contact with the vibration body 2.

[Vibrating body]
FIG. 1B is a schematic diagram illustrating the configuration of the vibrating body 2. The vibrating body 2 includes an electro-mechanical energy conversion element 2a and an elastic body 2b joined to the electro-mechanical energy conversion element 2a. The vibrating body 2 is held by the support member 4 by bonding the piezoelectric element 2 a to the support member 4. The electro-mechanical energy conversion element 2a is an element that converts an electrical quantity into a mechanical quantity, and a flat piezoelectric element is used in the sail embodiment. In the following description, the electromechanical energy conversion element 2a is referred to as a piezoelectric element 2a.

  In the following description, as shown in FIG. 1A, the relative movement direction (relative movement direction) between the vibrating body 2 and the driven body 3 is the X direction (first direction), and the thickness of the piezoelectric element 2a. Let the direction be the Z direction (second direction), and let the X direction and the direction orthogonal to the Z direction be the Y direction (third direction).

  The elastic body 2b includes a base portion 2c and a plurality of contact portions 2d provided so as to extend from the end portion in the Y direction of the base portion 2c. 2 d of contact parts are provided in the approximate center in the X direction of the elastic body 2b. The contact surface 2e provided on the driven body 3 side of each of the plurality of contact portions 2d abuts on the driven body 3 and frictionally drives the driven body 3. The elastic body 2b is a metal elastic member having magnetism, and uses, for example, martensitic stainless steel as a material. The elastic body 2b is subjected to, for example, a quenching process as a curing process for improving durability.

  FIG.1 (c) is a perspective view of the substantially cross-shaped metal plate which shows the state before the bending process of the elastic body 2b. The substantially cross-shaped metal plate has a base portion 2c and a contact portion 2d that are substantially cross-shaped by any one or some combination of cutting, laser processing, etching processing, punching processing, and the like. Manufactured by processing into a shape.

  As shown in FIG. 1B, this substantially cross-shaped metal plate is bent so that the angle between the base portion 2c and the contact portion 2d becomes an acute angle in the broken line portion 2f shown in FIG. 1C. In addition, a pair of contact portions 2d facing each other in the Y direction can be formed. The contact portion 2d is formed at an angle having a spring property so that the contact portion 2d can be brought into stable contact with the driven body 3. In the present embodiment, the angle formed by the base portion 2c and the contact portion 2d is set to approximately 70 degrees. The contact surface 2e with the driven body 3 provided in the contact portion 2d has its surface shape adjusted by lapping after bending so that the sliding surface of the driven body 3 can be smoothly contacted. Yes.

  As described above, the elastic body 2b is easily formed (manufactured) because the contact portion 2d that frictionally slides with the driven body 3 is integrally formed with the base portion 2c by bending. Moreover, in the vibrating body 2, since a non-joining area does not occur between the base 2c of the elastic body 2b and the piezoelectric element 2a, the bonding strength between the elastic body 2b and the piezoelectric element 2a can be increased.

  The support member 4 includes a flexible wiring board whose base film includes polyimide or the like, and includes a power feeding portion 4a, a thin plate portion 4b, a fixing portion 4c, a mounting hole portion 4d, and a connector connecting portion 4e.

  The power feeding unit 4a is bonded to the piezoelectric element 2a with an adhesive or the like, and applies a driving voltage to the piezoelectric element 2a. The fixing portion 4c is formed of a backing material of a flexible wiring board and is attached to a base (not shown). A method of attaching the fixing portion 4c to the base is not particularly limited. For example, the bottom surface of the fixing portion 4c (a surface facing the surface on which the vibrating body 2 is disposed) using the hole 4d for positioning. Can be used with a bonding agent or an adhesive. It is also desirable to pass through the hole 4d and fasten a screw or screw to a screw hole or hole provided in the base.

  The connection portion 4e is formed in a shape that can be inserted into a connector or the like, and is connected to a drive circuit (not shown) for driving the vibration type actuator 1.

  The thin plate portion 4b interposed between the power supply portion 4a and the fixed portion 4c is a thin flexible wiring board and is not joined to the piezoelectric element 2a. Therefore, the rigidity is lower than that of the fixed portion 4c. Accordingly, the thin plate portion 4b functions as a vibration insulating portion that reduces the propagation of the drive vibration excited by the vibrating body 2 to the fixed portion 4c. Since the support member 4 has the thin plate portion 4 b and can flexibly support the vibrating body 2, the supporting body 4 can hold the vibrating body 2 without inhibiting the vibration of the vibrating body 2.

  The driven body 3 includes a permanent magnet 5 that is a rectangular parallelepiped neodymium magnet, and a slider member 6 that is made of a metal elastic member having magnetism. The permanent magnet 5 is disposed between the slider member 6 and the vibrating body 2. The permanent magnet 5 and the slider member 6 are joined by an adhesive or the like. In the present embodiment, the slider member 6 is made of martensitic stainless steel.

  The slider member 6 includes a main body portion 6 a, a sliding portion 6 b having a sliding surface that is in frictional contact with the contact portion 2 d of the vibrating body 2, and a device to be driven by the vibration type actuator 1 and the slider member 6. It has the connection hole part 6c for connecting.

  The main body portion 6a is formed by bending or the like so that the sliding portion 6b has a shape closer to the vibrating body 2 than the surface where the permanent magnet 5 is joined.

  For example, nitriding treatment (curing treatment) is applied to the sliding surface of the sliding portion 6b that comes into frictional contact with the contact portion 2d of the vibrating body 2 as a hardening treatment for improving durability (wear resistance). . However, the present invention is not limited to this, and it may be formed by quenching or nickel plating on the surface. That is, the slider member 6 only needs to have a magnetic part and the frictional sliding surface has wear resistance.

  The method for attaching the connecting hole 6c to the device to be driven is not particularly limited. For example, the hole 6c is used for positioning, and the upper surface of the hole 6c is joined with an adhesive or an adhesive. The method can be used. Alternatively, a screw hole may be formed in the hole 6c and fastened to a device to be driven with a screw or the like.

  The permanent magnet 5 is disposed near the middle of the pair of contact portions 2d of the vibrating body 2 in the Y direction. The permanent magnet 5 is magnetized in the approximately Z direction, and the vibrating body 2 and the driven body 3 are attracted to each other in the approximately Z direction by the magnetic action of the permanent magnet 5. As a result, a pressing force is applied between the vibrating body 2 and the driven body 3 in a substantially Z direction. At this time, the vibration type actuator 1 is substantially line symmetric with respect to an X-direction straight line passing through the center of the vibration body 2. Therefore, the applied pressure generated between the vibrating body 2 and the driven body 3 is substantially the same at the two contact portions 2 d of the vibrating body 2, so that the frictional driving force that each contact portion 2 d applies to the driven body 3. Can be made equal in size. As a result, the resultant force of the frictional driving force applied to the driven body 3 by the two contact portions 2d can be efficiently generated in the X direction, so that the driving efficiency of the vibration actuator 1 can be increased.

  FIG. 2 is a YZ sectional view for explaining a magnetic circuit formed by the permanent magnet 5 in the vibration type actuator 1. FIG. 2A shows a cross section including the contact portion 2d, and FIG. 2B shows a cross section not including the contact portion 2d. FIGS. 2A and 2B schematically show the magnetic force lines I generated in the vibrating body 2 and the driven body 3 and the surrounding space.

  As shown in FIG. 2 (a), in the portion including the contact portion 2d, the lines of magnetic force I are generated from the surface of the permanent magnet 5 on the slider member 6 side (hereinafter referred to as "the upper surface of the permanent magnet 5"), and the permanent magnet 5 passes through the inside of the slider member 6 that is in contact with 5. The line of magnetic force I passes through the contact portion 2d of the elastic body 2b that contacts the sliding portion 6b from the slider member 6 and the base portion 2c located below the permanent magnet 5, and the surface on the base portion 2c side of the permanent magnet 5 through the air ( Hereinafter, it returns to “the bottom surface of the permanent magnet 5”). Due to the action of the lines of magnetic force I generated inside the elastic body 2 b by the permanent magnet 5, the elastic body 2 b is attracted to the permanent magnet 5 and the slider member 6. Since almost all the magnetic force lines I generated by the permanent magnet 5 pass through the slider member 6 and the elastic body 2b, the magnetic force of the permanent magnet 5 can be effectively used for the attraction action.

  Further, as shown in FIG. 2 (b), in a portion including only the base portion 2 c but not including the contact portion 2 d, the magnetic force lines I are generated from the upper surface of the permanent magnet 5, and the slider member 6 that abuts on the upper side of the permanent magnet 5. It passes through the inside. The magnetic force line I passes from the slider member 6 through the air through the base 2c located below the permanent magnet 5 and returns to the bottom surface of the permanent magnet 5 through the air again. Therefore, as in FIG. 2A, the elastic body 2 b is attracted to the permanent magnet 5 and the slider member 6 by the action of the magnetic lines of force I generated inside the elastic body 2 b by the permanent magnet 5. Thus, by arranging the slider member 6 and the elastic body 2b so as to sandwich the permanent magnet 5, the magnetic force of the permanent magnet 5 can be effectively used for the attraction action.

  Thus, a desired pressure can be generated between the sliding portion 6b and the contact portion 2d that are in contact with each other by the attractive action between the slider member 6 and the elastic body 2b generated by the permanent magnet 5. At this time, almost no leakage of magnetic flux to the space around the vibrating body 2 and the driven body 3 occurs, so that the magnetic force of the permanent magnet 5 can be efficiently applied as the applied pressure. Therefore, the permanent magnet 5 can be reduced in size, and the weight reduction and cost reduction of the driven body 3 can be expected.

  Note that the “line symmetry” in this specification does not have to be a complete line countermeasure, but may be substantially line symmetrical. Specifically, “line symmetry” in the present specification means that the permanent magnet 5 may be disposed at a position where it intersects a straight line in the Z direction passing through the center of gravity of the vibrating body 2 in the Y direction. Thereby, in the Y direction of the base 2c of the vibrating body 2, a suction force acts on both surfaces divided by a straight line in the Z direction passing through the center of gravity of the vibrating body 2, and the two contact portions 2d of the vibrating body 2 are substantially the same. A pressing force can be generated.

  Next, with reference to FIG. 3 and FIG. 4, two vibration modes excited by the vibrating body 2 will be described. Hereinafter, the two vibration modes excited by the vibrating body 2 are referred to as a first vibration mode and a second vibration mode. The drive vibration excited by the vibrating body 2 is a vibration in which the vibration in the first vibration mode and the vibration in the second vibration mode are combined.

  FIGS. 3A and 3B are perspective views for explaining deformation of the vibrating body 2 by the first vibration mode excited by the vibrating body 2. 3A and 3B, the displacement amount is enlarged (exaggerated) compared to the shape of the vibrating body 2 in order to make the change in the shape of the vibrating body 2 easier to understand.

  By the first vibration mode, primary bending vibration in the Y direction orthogonal to both the X direction and the Z direction is excited in the base 2 c of the vibrating body 2. The pair of contact portions 2d reciprocate in the Z direction by the vibration in the first vibration mode.

  FIGS. 4A and 4B are perspective views for explaining deformation of the vibrating body 2 by the second vibration mode excited by the vibrating body 2. 4A and 4B also show the displacement amount in an enlarged manner compared to the shape of the vibrating body 2 in order to make the change in the shape of the vibrating body 2 easier to understand.

  By the second vibration mode, secondary bending vibration in the X direction, which is the moving direction of the driven body 3, is excited in the base portion 2 c of the vibration body 2. This secondary bending vibration has three nodal lines substantially parallel to the Y direction. The pair of contact portions 2d reciprocate in the X direction by the vibration in the second vibration mode. Here, by disposing the contact portion 2d in the vicinity of a position that becomes a node in the vibration of the second vibration mode, the contact portion 2d can be displaced most greatly in the X direction.

  The X-direction and Y-direction dimensions of the base 2c of the elastic body 2b and the Z-direction dimensions and angles of the contact portion 2d are substantially equal to the natural frequency of the first vibration mode and the natural frequency of the second vibration mode. Designed to be.

  FIG. 5 is a plan view showing an electrode configuration of a joint surface of the support member 4 with the power feeding portion 4a in the piezoelectric element 2a. The piezoelectric element 2a has a structure in which electrodes are provided on the front and back surfaces of a plate-like piezoelectric ceramic that is an example of an electro-mechanical energy conversion element.

  Two electrodes of A phase and B phase are provided on the surface of the piezoelectric element 2 a that is joined to the power feeding portion 4 a of the support member 4. “+” Shown in FIG. 5 indicates the polarization direction of the piezoelectric ceramic, and indicates that the polarization direction of the piezoelectric ceramic is the same in each of the A-phase and B-phase electrode regions. In addition, on the surface joined to the elastic body 2b in the piezoelectric element 2a, one entire surface electrode (not shown) covering the entire surface is provided, and this entire surface electrode is used as a ground electrode (earth).

  When an alternating voltage having the same frequency and the same phase is applied to the A phase and the B phase in the vicinity of the natural frequency of the first vibration mode and the second vibration mode, the vibration of the first vibration mode is excited. . Further, when an alternating voltage having the same frequency and opposite phase is applied to the A phase and the B phase in the vicinity of the natural frequency of the first vibration mode and the second vibration mode, the vibration of the second vibration mode is excited. The Therefore, by applying an AC voltage having the same frequency and a phase difference that is neither in-phase nor anti-phase in the vicinity of the natural frequency to the A-phase and the B-phase, the vibration of the first vibration mode and the second frequency are applied to the vibrating body 2. The vibration of the vibration mode is simultaneously excited.

  By combining the vibration in the first vibration mode and the vibration in the second vibration mode, elliptical motion in a substantially XZ plane occurs on the contact surface 2e of the pair of contact portions 2d. The driven body 3 is frictionally driven in the direction substantially coincident with the X direction by the elliptical motion of the contact surface 2 e, and the driven body 3 can be linearly driven relative to the vibrating body 2. By applying an AC voltage delayed by 90 degrees to the B phase with respect to the A phase, the driven body 3 can be moved in one direction in the X direction, and advanced by 90 degrees to the B phase with respect to the A phase. By applying the AC voltage, the driven body 3 moves in the other direction in the X direction.

  FIG. 6 is a perspective view showing the movement range of the driven body 3. FIG. 6A shows a state in which the driven body 3 is driven to the plus side end in the X direction in the movement range of the driven body 3. FIG. 6B shows a state in which the driven body 3 is driven to the center of the movement range of the driven body 3, and FIG. 6C shows a negative side in the X direction in the movement range of the driven body 3. The state which driven the to-be-driven body 3 to the edge part is shown. In the present specification, the plus side in the X direction is the right side in FIG. 6A, and the minus side is the left side in FIG. 6A. In the following description, the plus side may be called the right side and the minus side may be called the left side. Further, in the following description, the movement range of the driven body 3 and the positive end of the permanent magnet 5 or the like may be referred to as a right end, and the negative end may be referred to as a left end.

  As shown in FIG. 6A, when the driven body 3 is driven rightward and positioned at the right end portion of the predetermined movement range, the left end portion 5-1 of the permanent magnet 5 of the driven body 3 is vibrated. The elastic body 2b of the body 2 is positioned on the right side of the left end 2b-1.

  From this state, by applying an AC voltage delayed by 90 degrees to the B phase with respect to the A phase, the driving direction of the driven body 3 changes to the minus side (left side) in the X direction. Then, the driven body 3 is driven to the left side and moves to the vicinity of the center of the movement range as shown in FIG. At this time, the left end 5-1 of the permanent magnet 5 of the driven body 3 is located on the left side of the left end 2b-1 of the vibrating body 2, and the right end 5-2 of the permanent magnet 5 is It is located on the right side of the right end 2b-2. That is, both ends of the vibrating body 2 in the X direction are located between both ends of the permanent magnet 5 in the X direction. When the driven body 3 further moves leftward from this state and the driven body 3 advances to the left end portion of the moving range as shown in FIG. 6C, the right end portion 5-2 of the permanent magnet 5 becomes the vibrating body. 2 on the left side of the right end 2b-2.

  Here, the driving direction is reversed by applying an AC voltage advanced by 90 degrees to the B phase with respect to the A phase, and the driven body 3 moves to the right end through the center, thereby moving a predetermined amount. The range can be driven back and forth.

  In addition, the end of the predetermined moving range can be detected by using a position sensor such as an optical encoder (not shown) or a Hall element, or by detecting the end using a photo sensor at both ends. It is. Moreover, you may provide the member which regulates positions, such as a stopper, in both ends so that the to-be-driven body 3 may not exceed the edge part of a movement range in the X direction from the contact part 2d.

  FIG. 7 is a diagram illustrating the relationship between the position of the driven body 3 and the suction force. A center line L in FIG. 7 is a straight line that passes through the center in the X direction of the elastic body 2b and is parallel to the Z direction and perpendicular to the X direction.

  FIG. 7A shows the suction force when the driven body 3 is located near the center within a predetermined movement range. In this case, the right end portion of the permanent magnet 5 is disposed on the right side of the right end portion of the elastic body 2b, and the left end portion of the permanent magnet 5 is disposed on the left side of the left end portion of the elastic body 2b.

  Further, when the driven body 3 is positioned near the center within a predetermined movement range, the elastic body 2b faces the permanent magnet 5 in the entire region in the X direction. That is, the area where the elastic body 2b and the permanent magnet 5 face on the right side in the X direction from the center line L, and the area where the elastic body 2b and the permanent magnet 5 face on the left side in the X direction from the center line L, Are approximately equal. Therefore, when viewed from the center line L in the X direction of the elastic body 2b, the suction force FL generated on the left side of the elastic body 2b and the suction force FR generated on the right side of the elastic body 2b have substantially the same magnitude. There is no moment around the Y axis.

  FIG. 7B shows the suction force when the driven body 3 is located at the right end within a predetermined movement range. In this case, the right end portion of the permanent magnet 5 is disposed on the right side of the right end portion of the elastic body 2b, and the left end portion of the permanent magnet 5 is disposed on the right side of the left end portion of the elastic body 2b.

  In addition, when the driven body 3 is located at the right end within a predetermined movement range, the elastic body 2b of the vibrating body 2 is in contact with the permanent magnet 5 and the entire region on the right side in the X direction from the center line L of the elastic body 2b. Is opposed to only a part on the left side. That is, the area where the elastic body 2b and the permanent magnet 5 face on the right side in the X direction from the center line L is larger than the area where the elastic body 2b and the permanent magnet 5 face on the left side in the X direction from the Miocene L. large. Therefore, when viewed from the center line L, the suction force FR generated on the right side of the elastic body 2b is larger than the suction force FL generated on the left side of the elastic body 2b.

  Therefore, a moment M around the Y axis is generated in the counterclockwise direction in the vibrating body 2. The thin plate portion 4 b of the support member 4 is made of a flexible wiring board, and the spring constant in the Z direction is lower than the spring constant in the Z direction of the contact portion 2 d of the vibrating body 2. As a result, the posture of the vibrating body 2 is tilted by elastic deformation of the thin plate portion 4b due to the moment M, and the contact surface 2e of the contact portion 2d has a stronger pressure on the right side of the center line L than on the left side.

  FIG. 7C shows the suction force when the driven body 3 is located at the left end within a predetermined movement range. In this case, the right end of the permanent magnet 5 is disposed on the left side of the right end of the elastic body 2b, and the left end of the permanent magnet 5 is disposed on the left side of the left end of the elastic body 2b.

  Further, when the driven body 3 is located at the left end within a predetermined movement range, the elastic body 2b of the vibrating body 2 is opposed to the permanent magnet 5 on the left side of the center line L in the entire region in the X direction. On the other hand, on the right side, it is only partly facing. That is, the area where the elastic body 2b and the permanent magnet 5 face on the left side in the X direction from the center line L is larger than the area where the elastic body 2b and the permanent magnet 5 face on the right side in the X direction from the Miocene L. large. Therefore, when viewed from the center line L, the suction force FL generated on the left side of the elastic body 2b is larger than the suction force FR generated on the right side of the elastic body 2b.

  Therefore, a moment M about the Y axis is generated in the clockwise direction in the vibrating body 2. As a result, the vibrating body 2 is tilted by the elastic deformation of the thin plate portion 4b due to the moment M, and the contact surface 2e of the contact portion 2d has a stronger pressure on the left side of the center line L than on the right side.

  FIG. 8 is a diagram illustrating a locus of elliptical motion generated on the contact surface 2e of the contact portion 2d when viewed in the XZ plane. As shown in FIG. 8, in the elliptical locus EC generated at the center of the contact portion 2e, the major axis of the ellipse is substantially parallel to the Z direction. Further, as the distance from the center portion to the end portion of the contact portion 2e is increased, the elliptical locus is inclined in the X direction, and the elliptical locus ER at the right end portion and the elliptical locus EL at the left end portion are inclined in a direction in which the long axis is directed toward the center line L. Yes.

  Here, as shown in FIG. 7B, when the driven body 3 is located at the right end, the right side of the contact surface 2e becomes a strong pressure. Therefore, the elliptical motion in which the major axis generated on the right side in the X direction from the center line L is inclined in the direction toward the central line L is the elliptical motion generated on the left side in the X direction from the center line L and the elliptical locus EC of the central portion. It contributes to the driving of the driven body 3 rather than the movement. Therefore, the elliptical motion of the elliptical locus inclined from the Z direction to the negative side in the X direction contributes by driving the driven body 3, and the driving force for driving the driven body 3 to the negative side in the X direction increases. To do.

  On the other hand, as shown in FIG. 7C, when the driven body 3 is located at the left end, the left side of the contact surface 2e becomes a strong pressure. Therefore, the elliptical motion in which the long axis generated on the left side in the X direction from the center line L is inclined in the direction toward the central line L is the elliptical motion generated on the right side in the X direction from the center line L and the elliptical locus EC of the central portion. It contributes to the driving of the driven body 3 rather than the movement. Therefore, the elliptical motion of the elliptical locus tilted from the Z direction to the plus side in the X direction contributes by driving the driven body 3, and the driving force for driving the driven body 3 to the plus side in the X direction increases. To do.

  With such a configuration, the startability when the driven body 3 moves to the end of the predetermined moving range and the driving direction is reversed is improved.

  Therefore, according to the vibration type actuator of the present embodiment, since the driving force is increased at both ends of the movement range of the driven body, even if wear occurs, the vibration type actuator is more effective than the conventional vibration type actuator. It is possible to reduce a decrease in startability.

  Further, when the driven body 3 is positioned at the end of the moving range, the vibrating body 2 is in a posture in which it can easily start automatically due to a change in the left and right balance of the attractive force generated from the positional relationship between the permanent magnet 5 and the elastic body 2b. It has a changing structure. Therefore, when the driven body 3 reaches the end of the movement range and reverses the driving direction, it is possible to improve the startability without using the start by special control such as increasing the applied voltage. Therefore, it is possible to reduce the increase in motor loss of the vibration type actuator and the complexity of the drive circuit caused by performing special control at the time of activation.

  Here, in the present embodiment, when the driven body 3 is positioned at one end of the moving range in the X direction, the other end of the permanent magnet 5 is more than the other end of the elastic body 2b. The effect of being located on one side will be described. Here, the case where the driven body 3 moves to the right side in the X direction will be described as an example. However, when the driven body 3 moves to the left side in the X direction, it is the same except that the direction in the X direction is different. Has an effect.

  FIG. 9A shows the change in the difference between the suction force FR generated on the right side of the elastic body 2b and the suction force FL generated on the left side of the elastic body 2b with respect to the change in position when the driven body 3 moves to the right side. FIG. In addition, it has shown in the ratio which remove | divided the suction force difference of right and left by the suction force FR of the right side. FIG. 9B is a schematic diagram illustrating the states of the position A, the position B, and the position C of the driven body 3 illustrated in FIG. At position A, the driven body 3 is located at the center of the movement range. In the position B, the left end 5-1 of the permanent magnet 5 of the driven body 3 and the left end 2b-1 of the elastic body 2b of the vibrating body 2 are located at the same position in the X direction. In the position C, the left end 5-1 of the permanent magnet 5 is located on the right side in the X direction with respect to the left end 2b-1 of the elastic body 2b.

  As shown in FIGS. 9A and 9B, the difference between the suction forces FR and FL is small while the driven body 3 moves from the position A to the position B, and the moment about the Y axis generated in the vibrating body 2 is also small. It hardly occurs. On the other hand, while the driven body 3 moves from the position B to the position C, the difference between the suction force FR and the suction force FL increases, and the moment about the Y axis generated in the vibrating body 2 also increases. Therefore, even if there is a manufacturing error such as uneven thickness on the left and right sides of the permanent magnet 5, a sufficient difference in attractive force is generated. If the end of the predetermined movement range of the driven body 3 is set on the drive direction side of the position B where the suction force difference starts to increase, the startability at the end can be improved.

  In the present embodiment, the right end of the moving range is such that the left end 5-1 of the permanent magnet 5 is located on the right side of the left end 2b-1 of the elastic body 2b, and the left end of the moving range is the right end of the permanent magnet 5. The movement range is defined so that the part 5-2 is located on the left side of the right end part 2b-2 of the elastic body 2b. For this reason, when the driven body 3 is located at one end of the predetermined moving range, the suction force difference generated between the left and right of the elastic body 2b becomes large, and the moment about the Y axis generated in the vibrating body 2 As a result, the posture of the vibrating body 2 is changed, and the startability can be improved.

  In the present embodiment, the angle formed by the contact portion 2d and the base portion 2c is approximately 70 degrees. However, the angle formed between the contact portion 2d and the base portion 2c is not limited to this, and has a spring property capable of stably contacting the driven body 3, and each of the first vibration mode and the second vibration mode. Any angle may be used as long as the resonance frequencies can be substantially matched.

  In the above description, as a method of controlling the driving direction of the driven body 3, a method of switching the phase difference of the AC voltage applied to the A phase and the B phase of the piezoelectric element 2a between +90 degrees and -90 degrees is used. It was. However, the phase difference of the AC voltage applied to the A phase and the B phase of the piezoelectric element 2a is not limited to this, and is 0 ° to ± 180 ° depending on the relative moving speed of the driven body 3 and the vibrating body 2. Can vary in range.

  In the above description, as shown in FIG. 5, the electrode structure of the piezoelectric element 2a is divided into two parts in the X direction. However, the electrode configuration of the piezoelectric element 2a is not limited to this, and any configuration is possible as long as the respective vibrations of the first vibration mode and the second vibration mode can be excited simultaneously. Furthermore, in the above description, the contact portion 2d of the elastic body 2b is formed by bending a substantially cross-shaped metal plate. However, the method of forming the contact portion 2d is not limited to this, and other methods such as cutting can be used as long as a desired shape is obtained.

  In the above description, the vibrating body 2 is supported using a flexible wiring board as the support member 4. However, the configuration of the support member that supports the vibrating body 2 is not limited to this, and a supporting member is configured by joining a part of the vibrating body 2 by welding or the like made of a thin metal material separately from the flexible wiring board for power supply. May be. In that case, the posture of the vibrating body 2 is tilted by the moment generated by the suction force difference by configuring the supporting member so that the spring constant in the Z direction is lower than the spring constant in the Z direction of the contact portion 2d of the vibrating body 2. be able to.

  Next, a modification of the vibration type actuator 1 of the present embodiment will be described with reference to FIG. FIG. 10A is a schematic perspective view illustrating the configuration of a vibration type actuator 11 according to a modification.

  The vibration type actuator 11 includes a vibration body 12 and a driven body 13 that is in pressure contact with the vibration body 12. The vibrating body 12 is held by a support portion (not shown). FIG. 10B is a schematic perspective view illustrating the structure of the vibrating body 12. The vibrating body 12 includes an elastic body 12b, a piezoelectric element 12a provided on a surface of the elastic body 12b opposite to the surface on which the contact portion 12d is provided, and the elastic body 12b. Have.

  The contact portion 12d is formed with a thickness (height) having springiness, and is formed integrally with the elastic body 12b by, for example, pressing a plate material constituting the elastic body 12b. However, the contact portion 12d is not limited thereto, and may be fixed to the elastic body 12b by welding or the like.

  The driven body 13 includes a permanent magnet 15 and a sliding plate 16 b that is a friction sliding surface with the vibrating body 12. The sliding plate 16b is subjected to a curing process such as a nitriding process in order to improve the wear resistance, and is bonded to the permanent magnet 15 using an adhesive. Due to the attractive force acting between the permanent magnet 15 and the elastic body 12b constituting the vibrating body 22, the vibrating body 12 and the driven body are in contact with each other with a predetermined pressure.

  Also in the vibration type actuator 11 according to this modification, when the driven body 13 is located at one end of the moving range, the other end of the permanent magnet 15 is the other end of the elastic body 12b. It is arrange | positioned rather than the part.

  That is, when the driven body 13 is located at the end on the plus side in the X direction of the moving range, the end 15-1 of the permanent magnet 15 is on the plus side in the X direction with respect to the end 12b-1 of the elastic body 12b. Placed in. Further, when the driven body 13 is positioned at the end on the minus side in the X direction of the movement range, the end 15-2 of the permanent magnet 15 is on the minus side in the X direction with respect to the right end 12b-2 of the elastic body 12b. The movement range is defined so as to be arranged in Therefore, when the driven body 13 is located at one end of the moving range, a difference in suction force generated between the plus side and the minus side in the X direction of the elastic body 12b becomes large, and the Y axis generated in the vibrating body 12 The posture of the vibrating body 12 is changed by the surrounding moment. Thereby, it is possible to improve the startability, and even if wear occurs, it is possible to reduce the decrease in the startability of the vibration type actuator.

(Second Embodiment)
The configuration of the vibration type actuator 21 according to the present embodiment will be described with reference to FIG. FIG. 11A is a schematic diagram illustrating the configuration of the vibration type actuator 21. FIG. 11B is a schematic diagram of a cross section of the vibration type actuator 21 when viewed in the YZ plane, passing through the center of the driven body 23 of the vibration type actuator 21. FIG. 11C is a schematic view of the driven body 23 of the vibration type actuator 21 as viewed from the vibration body 2 side.

  The vibration type actuator 21 uses a driven body 23 instead of the driven body 3 of the vibration type actuator 1 according to the first embodiment. The vibration type actuator 21 is a vibration type actuator that rotationally drives the driven body 23. Note that in the vibration type actuator 21, the same components as those of the vibration type actuator 1 according to the first embodiment are denoted by the same reference numerals as those in the first embodiment, and detailed description thereof is omitted.

  The driven body 23 is configured by joining a permanent magnet 25, which is an annular neodymium magnet, and a rotor member 26 made of an annular metal elastic member having magnetism with an adhesive or the like. In this embodiment, martensitic stainless steel is used as the material of the rotor member 26.

  The rotor member 26 includes a main body portion 26a and a sliding portion 26b having a sliding surface that is in frictional contact with the contact portion 2d of the vibrating body 2. A nitriding treatment (curing treatment) is applied to the sliding surface that comes into frictional contact with the contact portion 2d of the vibrating body 2 of the sliding portion 26b. The main body 26a is connected to a device to be driven (not shown) and transmits a rotational force to the drive target.

  The permanent magnet 25 is magnetized in the substantially Z direction, and the vibrating body 2 and the driven body 23 are attracted to each other in the approximately Z direction by the magnetic action of the permanent magnet 25. Thereby, a pressing force is applied between the vibrating body 2 and the driven body 23 in the substantially Z direction. The permanent magnet 25 has an annular shape but is partially open, and has a first end 25-1 and a second end 25-2.

  FIG. 12 is a perspective view showing the movement range of the driven body 23. In FIG. 12, the support member 4 is not shown. FIG. 12A shows a state in which the driven body 23 is driven to the end in the CW direction in the movement range of the driven body 23, and FIG. 12B shows the driven body 23 to the end in the CCW direction. The state which driven is shown.

  As shown in FIG. 12A, when the driven body 23 is located at the end of the moving range on the CW direction side, the first end 25-1 on the side opposite to the CW direction of the permanent magnet 25 is The elastic body 2b is located on the drive direction side, that is, on the CW direction side with respect to the end 2b-1 on the opposite side to the CW direction. In this case, the permanent magnet 25 of the elastic body 22b of the vibrating body 22 is opposed to the permanent magnet 25 in the entire region in the driving direction on the CW direction side, whereas the elastic body 22b is a part of the CCW side. Is not facing the permanent magnet. In other words, the vibrating body 22 faces the open portion of the permanent magnet 25 on the CCW side.

  In this case, the area where the elastic body 2b faces the permanent magnet 25 on one side (CW side) from the center line (not shown) of the elastic body 2b, and the elastic body 2b and permanent magnet on the other side (CCW side). It becomes larger than the area which 25 opposes. Therefore, the suction force generated on the CW side is larger than the suction force generated on the CCW direction side of the elastic body 2b, and a moment about the Y axis is generated in the clockwise direction in the vibrating body 2. Therefore, the posture of the vibrating body 2 is inclined, the contact surface 2e of the contact portion 2d has a stronger pressure on the CW side than on the CCW side, and the driving force for driving the driven body 23 in the CCW direction increases.

  From this state, when the phase difference of the B phase is changed, the rotation direction is reversed and the driven body 23 is driven to the end in the CCW direction, the second end of the permanent magnet 25 as shown in FIG. 25-2 is located in the drive direction side rather than the edge part 2b-2 of the elastic body 2b of the vibrating body 2. As shown in FIG. In this case, the permanent magnet 25 of the elastic body 22b of the vibrating body 22 is opposed to the permanent magnet 25 in the entire region in the driving direction on the CW direction side, whereas the elastic body 22b is a part of the CCW side. Is not facing the permanent magnet. That is, on the CCW side, the vibrating body 22 faces the open portion of the permanent magnet 25 on the CW side.

  In this case, the area where the elastic body 2b faces the permanent magnet 25 on one side (CCW side) from the center line (not shown) of the elastic body 2b, and the elastic body 2b and permanent magnet on the other side (CW side). It becomes larger than the area which 25 opposes. Therefore, the suction force generated on the CCW side is larger than the suction force generated on the CW direction side of the elastic body 2b, and a moment about the Y axis is generated in the counterclockwise direction on the vibrating body 2. Therefore, the posture of the vibrating body 2 is inclined, and the contact surface 2e of the contact portion 2d has a stronger pressure on the CCW side than on the CW side, and the driving force for driving the driven body 23 in the CW direction increases.

  As described above, when the driven body 23 moves to the end of the predetermined movement range, the startability when the driving direction is reversed is improved.

  As a result, even when the predetermined moving range is rotationally driven as in the present embodiment, even if the driven body 23 is worn, the decrease in the startability is reduced as compared with the conventional vibration type actuator. can do.

(Third embodiment)
In the present embodiment, a configuration of an imaging apparatus as an example of an apparatus (machine) including the vibration type actuator according to the above-described embodiment will be described with reference to FIG. FIG. 13A is a schematic top view illustrating the configuration of the imaging apparatus 700. FIG.

  The imaging apparatus 700 includes a camera body 730 on which an imaging element 710 and a power button 720 are mounted. In addition, the imaging apparatus 700 includes a lens barrel 740 having a first lens group (not shown), a second lens group 320, a third lens group (not shown), a fourth lens group 340, and vibration type driving devices 620 and 640. Is provided. The lens barrel 740 can be replaced as an interchangeable lens, and a lens barrel 740 suitable for a subject to be photographed can be attached to the camera body 730. In the imaging device 700, the second lens group 320 and the fourth lens group 340 are driven by the two vibration type driving devices 620 and 640, respectively.

  The vibration type driving device 620 includes, for example, a vibration type actuator including the vibrating body 2 and the annular driven body described in the first embodiment, and a driving circuit that applies a driving voltage to the piezoelectric element 2a of the vibrating body 2. Have. The driven body is disposed in the lens barrel 740 so that the radial direction is substantially orthogonal to the optical axis. The driven body is arranged in the lens barrel 740 and has parallel surfaces that are substantially orthogonal to the optical axis and are opposed in the optical axis direction. For example, the three vibrating bodies 2 sandwich the parallel surfaces facing each other in the optical axis direction in the driven body between the pair of contact portions 2d, and apply thrust to the driven body in the tangential direction of the circle centering on the optical axis. As shown, they are arranged at substantially equal intervals on the circumference centered on the optical axis.

  With such a configuration, the vibration type driving device 620 rotates the driven body around the optical axis, and converts the rotation output of the driven body into a linear motion in the optical axis direction via a gear or the like, thereby The two lens group 320 can be moved in the optical axis direction. The vibration type driving device 640 has the same configuration as that of the vibration type driving device 620, thereby moving the fourth lens group 340 in the optical axis direction.

  FIG. 13B is a block diagram illustrating a schematic structure of the imaging apparatus 700. The first lens group 310, the second lens group 320, the third lens group 330, the fourth lens group 340, and the light amount adjustment unit 350 are arranged at predetermined positions on the optical axis inside the lens barrel 740. The light that has passed through the first lens group 310 to the fourth lens group 340 and the light amount adjustment unit 350 forms an image on the image sensor 710. The image sensor 710 converts the optical image into an electrical signal and outputs the electrical signal, and the output is sent to the camera processing circuit 750.

  The camera processing circuit 750 performs amplification, gamma correction, and the like on the output signal from the image sensor 710. The camera processing circuit 750 is connected to the CPU 790 through the AE gate 755 and is connected to the CPU 790 through the AF gate 760 and the AF signal processing circuit 765. The video signal that has undergone predetermined processing in the camera processing circuit 750 is sent to the CPU 790 through the AE gate 755, the AF gate 760, and the AF signal processing circuit 765. The AF signal processing circuit 765 extracts a high frequency component of the video signal, generates an evaluation value signal for autofocus (AF), and supplies the generated evaluation value to the CPU 790.

  The CPU 790 is a control circuit that controls the overall operation of the imaging apparatus 700, and generates a control signal for determining exposure and focusing from the acquired video signal. The CPU 790 controls the driving of the vibration type driving devices 620 and 640 and the meter 630 so that the determined exposure and an appropriate focus state can be obtained, so that the second lens group 320, the fourth lens group 340, and the light amount adjustment unit are controlled. The position of 350 in the optical axis direction is adjusted. Under the control of the CPU 790, the vibration type driving device 620 moves the second lens group 320 in the optical axis direction, the vibration type driving device 640 moves the fourth lens group 340 in the optical axis direction, and the light quantity adjustment unit 350 is a meter. Drive control is performed by 630.

  The position in the optical axis direction of the second lens group 320 driven by the vibration type driving device 620 is detected by the first linear encoder 770, and the detection result is notified to the CPU 790, which is fed back to the driving of the vibration type driving device 620. The Similarly, the optical axis direction position of the fourth lens group 340 driven by the vibration type driving device 640 is detected by the second linear encoder 775, and the detection result is notified to the CPU 790, so that the vibration type driving device 640 is driven. Feedback. The position in the optical axis direction of the light amount adjustment unit 350 is detected by the diaphragm encoder 780, and the detection result is notified to the CPU 790, which is fed back to the drive of the meter 630.

  When the vibration type actuator 1 or the like is used for moving the predetermined lens group of the imaging device 700 in the optical axis direction, a large holding force is maintained even when the lens group is stopped. Thereby, even if an external force acts on the lens barrel or the imaging apparatus main body, it is possible to suppress the occurrence of deviation in the lens group.

  Here, the example in which the lens group is moved in the optical axis direction using the vibration type driving devices 620 and 640 having the annular driven body has been described, but the lens group is moved in the optical axis direction using the vibration type actuator 1. The configuration to be moved is not limited to this. For example, the vibrating body 2 can linearly drive the driven body in the X direction as described in the first embodiment. Therefore, the lens group is moved in the optical axis direction by attaching the holding member holding the lens to the driven body 3 and configuring the optical axis direction of the lens and the driving direction of the driven body 3 to be substantially parallel. be able to.

  When a camera shake correction lens is built in the lens barrel, the vibrating body 2 can be used in a camera shake correction unit that moves the camera shake correction lens in any direction within a plane substantially orthogonal to the optical axis. . In that case, one or a plurality of vibrators 2 for driving the lens holding member are arranged in each direction so that the lens holding member can be moved in two directions orthogonal to each other in a plane substantially orthogonal to the optical axis direction. The camera shake correction unit may be configured to move the image sensor 710 built in the main body of the imaging device in an arbitrary direction within a plane orthogonal to the optical axis, instead of the configuration to drive the camera shake correction lens.

  When the vibration actuator 1 or the like is arranged in a device having a corner, the contact portion pair is formed at an acute angle, so that the space in the corner can be used efficiently and the entire device can be downsized. can do.

(Fourth embodiment)
In the fourth embodiment, refer to FIG. 14 for the configuration of a microscope including an XY stage as an example of an apparatus including at least two of the vibration-type actuators 1, 10, and 20 of the above-described embodiment. I will explain. FIG. 14 is an external perspective view of the microscope 400.

  The microscope 400 includes an imaging unit 410 that includes an imaging device and an optical system, and an automatic stage 430 that is provided on a base and includes a stage 420.

  The automatic stage 430 is a stage apparatus that includes a stage 420 and moves the stage 420 in the XY plane by any one of the vibration type actuators 1, 10, and 20 of the above-described embodiment. In addition, this embodiment does not limit the structure of a stage apparatus, The structure of a stage apparatus can be changed suitably.

  At least one of the vibration type actuators of the automatic stage 430 is used for driving in the X direction, and is arranged so that the X direction of the vibrating body 2 coincides with the X direction of the stage 420. Another one of the vibration type actuators of the automatic stage 430 is used for Y direction driving, and is arranged so that the X direction of the vibrating body 2 coincides with the Y direction of the stage 420.

  An object to be observed is placed on the upper surface of the stage 420 and an enlarged image is taken by the imaging unit 410. When the observation range is wide, a large number of captured images are acquired by driving the automatic stage 430 and moving the object to be observed by moving the stage 420 in the X direction or Y direction within the plane. By combining the captured images by image processing with a computer (not shown), it is possible to acquire a single image with a wide observation range and high definition.

  Although the present invention has been described in detail based on preferred embodiments thereof, the present invention is not limited to these specific embodiments, and various forms within the scope of the present invention are also included in the present invention. included. Furthermore, each embodiment mentioned above shows only one embodiment of this invention, and it is also possible to combine each embodiment suitably.

DESCRIPTION OF SYMBOLS 1 Vibrating actuator 2 Vibrating body 2a Electro-mechanical energy conversion element 2b Elastic body 3 Driven body 5 Permanent magnet

Claims (19)

A driven body having a permanent magnet;
An elastic body having magnetism and a vibrating body having an electromechanical energy conversion element joined to the elastic body,
By applying a driving voltage to the electro-mechanical energy conversion element, vibration is excited in the vibrating body, and the driven body and the vibrating body are relatively moved within a moving range in a relative movement direction by the vibration. A vibration type actuator,
In a state where the driven body has moved to one end of the relative movement direction of the moving range, the other end of the permanent magnet in the relative movement direction is the other side of the elastic body. It is arrange | positioned on the said one side rather than the edge part of this. In a state where the driven body is moving to the one end portion of the moving range, the one end portion of the permanent magnet is more on the one side than the one end portion of the elastic body. The vibration type actuator according to claim 1, wherein In a state where the driven body is arranged at the center of the moving range, the one end portion of the permanent magnet is arranged on the one side rather than the one end portion of the elastic body, and the permanent magnet 3. The vibration type actuator according to claim 1, wherein an end of the other side of the magnet is disposed closer to the other side than an end of the other side of the elastic body. The vibration type actuator according to any one of claims 1 to 3, wherein the elastic body has a contact portion having a contact surface in pressure contact with the driven body. The vibration type actuator according to claim 4, wherein the contact portion is formed to have a spring property, and is provided at a central portion in the first direction of the elastic body. A support portion for holding the vibrating body;
6. The vibration type actuator according to claim 4, wherein a spring constant in the thickness direction of the electromechanical energy conversion element of the support portion is lower than a spring constant in the thickness direction of the contact portion. The contact portion extends from an end portion in a direction orthogonal to the relative movement direction of the elastic body and the thickness direction of the electro-mechanical energy conversion element. The vibration type actuator according to item. The vibration type actuator according to any one of claims 4 to 7, wherein the contact portion is formed integrally with the elastic body by bending. The vibration type actuator according to any one of claims 1 to 8, wherein the permanent magnet is disposed at a center of the vibrating body in a direction perpendicular to the relative movement direction and the thickness direction. . The vibration type actuator according to any one of claims 1 to 9, wherein the vibration is a vibration obtained by combining two natural vibrations. In a state where the driven body is moving to one end of the relative movement direction of the movement range, the attractive force of the permanent magnet on the one side from the center of the relative movement direction of the elastic body is 11. The vibration type actuator according to claim 1, wherein the vibration type actuator has a larger attractive force than the permanent magnet on the other side of the center. A driven body having a permanent magnet;
An elastic body having magnetism and a vibrating body having an electromechanical energy conversion element joined to the elastic body,
By applying a driving voltage to the electro-mechanical energy conversion element, vibration is excited in the vibrating body, and the driven body and the vibrating body are relatively moved within a moving range in a relative movement direction by the vibration. A vibration type actuator,
In a state where the driven body is disposed at one end of the moving range in the moving direction, it faces the permanent magnet of the elastic body on the one side in the moving direction from the center line of the vibrating body. The vibration type actuator is characterized in that the area of the area to be operated is larger than the area of the area on the other side in the moving direction. In a state where the driven body is disposed at the center of the movement range, the area of the region on the one side from the center line is equal to the area of the region on the other side from the center line. The vibration type actuator according to claim 12, wherein The vibration type actuator according to claim 12, wherein the elastic body has a contact portion having a contact surface that contacts the driven body. A lens,
A lens barrel comprising: the vibration type actuator according to claim 1, wherein the lens is moved in an optical axis direction. An image blur correction lens,
The vibration type actuator according to any one of claims 1 to 14, wherein the lens is moved in a plane orthogonal to an optical axis. A lens barrel;
The vibration type actuator according to any one of claims 1 to 14, wherein a lens disposed in the lens barrel is moved in an optical axis direction.
An imaging device comprising: an imaging element that converts an optical image of light that has passed through the lens barrel into an electrical signal. A lens barrel;
An image sensor that converts an optical image of light that has passed through the lens barrel into an electrical signal;
The vibration type actuator according to any one of claims 1 to 14, wherein the image pickup device is moved in a plane orthogonal to an optical axis direction to correct an image blur of an optical image formed on the image pickup device. An imaging apparatus comprising: Stage,
A stage apparatus comprising: the vibration type actuator according to any one of claims 1 to 14, wherein the stage is moved in a plane thereof.

Images