JP2017143659A - Turning drive unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a turning drive unit that has a high general purpose, a small size, and excellent controllability.SOLUTION: A monitor camera, which is an example of a turning drive device, comprises: a camera body 110; a turning frame body 120 that pivotally supports the camera body 110 so as to freely rotate it around a first rotation axis L1; a base part 130 that pivotally supports the turning frame body 120 around a second rotation axis L2 orthogonal to the first rotation axis L1; and two vibration type actuators 101a, 101b arranged on the base part 130. A driven body 103 of each of the vibration type actuators 101a, 101b is connected to a camera body 110. By driving each of the two driven bodies 103 in the same direction as a third direction substantially orthogonal to both the first rotation axis L1 and the second rotation axis L2, the camera body 110 is rotated around the first rotation axis L1. By driving it in a direction opposite the third direction, the camera body 110 and the turning frame body 120 are integrally rotated around the second ration axis L2.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a turning drive device using a vibration type actuator that brings a vibrating body and a driven body into pressure contact and moves the vibrating body and the driven body relatively by vibration excited by the vibrating body.

  A turning drive device is known that utilizes the high-precision and silent drive that is characteristic of a vibration actuator (see Patent Document 1). FIG. 9 is a side view showing a schematic configuration of a stage device 400 which is an example of a known turning drive device. In stage device 400, case 420 is fixed to the drive shaft of vibration actuator 401a for pan driving, and vibration actuator 401b for tilt driving is fixed to case 420. A turning stage 410 is fixed to the drive shaft of the vibration type actuator 401b for tilt driving. With such a configuration, by driving the vibration type actuator 401b, it is possible to perform tilt driving in which only the turning stage 410 is rotated about the first rotation axis L1. Then, by driving the vibration type actuator 401a, it is possible to perform pan driving in which the case 420, the vibration type actuator 401b, and the turning stage 410 are integrally rotated about the second rotation axis L2.

  As another example of the swivel drive device, a sphere that is rotatable around each of two axes substantially orthogonal to each other is used as a rotator, and the rotator is provided with two or more piezoelectric drive units for rotationally driving the rotator. An apparatus has been proposed (see Patent Document 2). Each of the two or more piezoelectric drive units is a first operation mode in which the rotating body is rotated, and a second operation mode in which the frictional force between the non-rotating piezoelectric drive unit and the rotating body is reduced by longitudinal vibration. Can be driven.

JP 2005-37724 A JP 2001-211676 A

  However, in the stage apparatus 400 described above, not only the turning stage 410 but also the vibration actuator 401b for tilt driving and the case 420 are integrally rotated around the second rotation axis L2 during pan driving. For this reason, a large torque is required for the vibration actuator 401a for driving the pan, and there is a problem that the vibration actuator 401a for driving the pan is increased in size, and the entire stage device 400 is increased in size. In addition, since the vibration actuator 401b for tilt driving rotates around the second rotation axis L2, it is necessary to use a slip ring or the like for supplying power to the vibration actuator 401b for tilt driving, and accordingly. There is a problem that the stage device becomes large. Further, since the vibration type actuator 401b for tilt driving is arranged on the outer diameter side of the turning stage 410, the inertia at the time of pan driving increases, and the positioning accuracy and responsiveness of the turning stage 410 may be lowered. is there. In addition, it is necessary to secure a space where the vibration actuator 401b for tilt driving can be moved at a place where the stage apparatus 400 is installed, and there is a problem that the installation place is limited.

  The rotational drive device described in Patent Document 2 has a configuration in which a rotating body is driven using a plurality of piezoelectric drive units, and thus the above-described problem with respect to the stage device 400 does not occur. However, in order to rotate the spherical rotating body in a predetermined direction, one of the plurality of piezoelectric driving units is driven in the first operation mode, and the remaining friction force between the rotating body and the rotating body is reduced. In order to do so, it is necessary to drive in the second operation mode, which causes a problem of increased power consumption. Further, since the rotating body is in contact with the piezoelectric drive unit on the surface thereof, high-precision processing is required on the surface of the rotating body, and the production cost increases. Furthermore, since the rotating body is spherical, there is a problem that the shape and size of a member (for example, a camera or the like) attached to the turning stage is greatly limited as compared with a flat plate stage.

  An object of the present invention is to provide a turning drive device that is highly versatile, small in size, and excellent in controllability.

  The turning drive device according to the present invention includes a first rotating body, a second rotating body that rotatably supports the first rotating body about an axis of the first axis, and the first shaft. A base part that rotatably supports the second rotating body around an axis of a second axis that is substantially orthogonal, and two vibration actuators disposed on the base part, and the two Each of the vibration type actuators includes a support member supported by the base portion, a vibration body held by the support member, and vibrations excited by the vibration body, so that the first shaft and the second shaft A driven body driven in the axial direction of a third axis that is substantially orthogonal to both of the two driven actuators, wherein the driven bodies of the two vibration actuators are coupled to the first rotating body, The driven bodies of the two vibration actuators are the same in the axial direction of the third axis. The first rotating body rotates about the axis of the first axis when driven, and the driven bodies of the two vibration actuators are respectively opposite to the axial direction of the third axis. When driven, the first rotating body and the second rotating body integrally rotate about the axis of the second shaft.

  According to the present invention, it is possible to realize a turning drive device that is highly versatile, small in size, and excellent in controllability.

It is the perspective view and exploded perspective view which show schematic structure of the surveillance camera which concerns on 1st Embodiment of this invention. It is a side view of the surveillance camera shown in FIG. FIG. 2 is an exploded perspective view showing a schematic configuration of a vibration type actuator constituting the surveillance camera shown in FIG. 1 and a perspective view for explaining a vibration mode of vibration excited by a vibrating body constituting the vibration type actuator. It is a perspective view which shows the state which pan-driven the surveillance camera shown in FIG. FIG. 2 is a perspective view showing a state where the surveillance camera shown in FIG. 1 is tilt-driven. It is a perspective view of the stage apparatus which concerns on the modification of the surveillance camera shown in FIG. It is the perspective view which shows schematic structure of the surveillance camera which concerns on 2nd Embodiment of this invention, and the exploded perspective view which shows the vibration type actuator which comprises a surveillance camera, and its surrounding structure. It is a figure (side view) explaining another structure which pressurizes a vibrating body and a to-be-driven body in the vibration type actuator which comprises the surveillance camera shown in FIG. It is a side view which shows schematic structure of a known stage apparatus.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this embodiment, a surveillance camera and a stage device are taken up as the turning drive device according to the present invention. However, the turning drive device according to the present invention is not limited to such applications.

  A first embodiment of the present invention will be described. Fig.1 (a) is a perspective view which shows schematic structure of the surveillance camera 100 which concerns on 1st Embodiment of this invention. FIG. 1B is an exploded perspective view of the monitoring camera 100. For convenience of explanation, as shown in FIGS. 1A and 1B, an X direction (X axis), a Y direction (Y axis), and a Z direction (Z axis) that are orthogonal to each other are defined for the surveillance camera 100. . And the surveillance camera 100 shall be arrange | positioned so that XY plane may become substantially parallel to a horizontal surface and a Z-axis may become substantially parallel to a perpendicular direction. “Substantially parallel” means that it can be regarded as substantially parallel, and does not need to be strictly parallel.

  The monitoring camera 100 includes vibration type actuators 101a and 101b, a camera body 110 (first rotating body (imaging device)), a turning frame body 120 (second rotating body), and a base 130. The camera body 110 includes a lens unit 111, two attachment portions 112, and two first rotation shaft portions 113. The revolving frame 120 has a second rotating shaft portion 122 and first bearings 121 provided at two locations. The base part 130 includes a second bearing 131 and two guide pins 132.

  Each of the two first rotating shaft portions 113 provided in the camera body 110 is a round rod-shaped shaft having a first rotating axis L1 (first axis) substantially orthogonal to the optical axis L3 of the lens portion 111 as a central axis. And inserted into the first bearing 121 provided on the revolving frame 120. As a result, the camera body 110 is pivotally supported by the revolving frame 120 so as to be rotatable about the first rotation axis L1. Note that the first bearing 121 is a rolling bearing or a sliding bearing. The second rotating shaft portion 122 of the revolving frame body 120 is a round bar-shaped shaft having the second rotating shaft L <b> 2 (second axis) as a central axis, and the second bearing 131 provided on the base portion 130. Inserted into. Thereby, the revolving frame 120 is pivotally supported by the base portion 130 so as to be rotatable about the second rotation axis L2. The second bearing 131 is a rolling bearing or a sliding bearing.

  Here, as shown in FIG. 1, the second rotation axis L2 is substantially parallel to the Z direction, and the first rotation axis L1 and the second rotation axis L2 are substantially orthogonal. Here, the fact that the first rotation axis L1 and the second rotation axis L2 are substantially orthogonal allows tilt drive and pan drive of the camera body 110 independently in consideration of component errors and assembly errors. It means crossing at a certain angle and does not need to be strictly orthogonal. It is similarly defined that the optical axis L3 of the lens unit 111 and the first rotation axis L1 are substantially orthogonal to each other.

  The camera body 110 and the turning frame body 120 are integrally rotatable about the second rotation axis L2 with respect to the base portion 130, and the camera body 110 is rotated with respect to the turning frame body 120 by the first rotation axis L1. It can rotate freely. As described above, in the present embodiment, since the Z direction is substantially parallel to the vertical direction, the second rotation axis L2 is substantially parallel to the vertical direction, and the first rotation axis L1 is substantially parallel to the horizontal direction. It is. Therefore, in the following description, driving for rotating the camera body 110 about the first rotation axis L1 as appropriate is referred to as tilt driving, and the camera body 110 and the turning frame body 120 are integrated with each other about the second rotation axis L2. The drive that is rotated at a time is called pan drive.

  When the surveillance camera 100 is in a state where the first rotation axis L1 is substantially parallel to the Y direction as shown in FIG. It is provided at a position that is substantially symmetric in the Y direction about the second rotation axis L2. The two attachment portions 112 are in contact with the revolving frame body 120 in a state where the camera body 110 is supported by the revolving frame body 120 by the first rotating shaft portion 113 being pivotally supported by the first bearing 121. Absent. The two attachment portions 112 are respectively connected to the driven bodies 103 (see FIG. 3) of the vibration type actuators 101a and 101b via a universal joint 105 (see FIG. 2) which is an example of a connecting member. As will be described later, the two guide pins 132 provided on the base 130 serve to support the vibration type actuators 101a and 101b.

  FIG. 2 is a side view of the monitoring camera 100 and shows a state in the home position. The home position indicates a state in which the rotation angle of pan driving (hereinafter referred to as “pan angle”) and the rotation angle of tilt driving (hereinafter referred to as “tilt angle”) are 0 degrees. Therefore, at the home position, the first rotation axis L1 is substantially parallel to the Y direction, and the optical axis L3 of the lens unit 111 is substantially parallel to the X direction. At the home position, when viewed from the Y direction, the center of the top part 105b of the universal joint 105 that connects the driven body 103 of one vibration type actuator 101a and one mounting part 112 of the camera body 110 is the second rotation. Located on axis L2. The same applies to the other vibration type actuator 101b (not shown in FIG. 2). Details of the universal joint 105 will be described later.

  FIG. 3A is an exploded perspective view showing a schematic configuration of the vibration type actuator 101a. Since both the vibration type actuators 101a and 101b have the same structure, the description of the vibration type actuator 101b is omitted. The vibration type actuator 101 a includes a vibration body 102, a driven body 103, and a support member 104. The vibrating body 102 is provided on the opposite surface of the elastic body 102b, the fixed portion 102d, the two protrusions 102c provided on one surface of the elastic body 102b, and the surface of the elastic body 102b on which the protrusion 102c is provided. The piezoelectric element 102a is provided. Here, a configuration in which the driven body 103 is frictionally driven by the two protrusions 102 c is taken up as the vibrating body 102, but in order to frictionally drive the driven body 103, at least one protrusion 102 c is sufficient.

  The elastic body 102b has a substantially rectangular flat plate shape and is made of, for example, a metal material such as martensitic stainless steel. A fixing portion 102d for fixing the vibrating body 102 to the support member 104 is provided integrally with the elastic body 102b at the longitudinal end of the vibrating body 102. The protrusion 102c is formed with a thickness (height) having spring properties, and is formed integrally with the elastic body 102b by, for example, pressing a plate material constituting the elastic body 102b. However, the protrusion 102c is not limited thereto, and may be fixed to the elastic body 102b by welding or the like. Since the tip portion (upper surface) of the protrusion 102c slides frictionally with the sliding portion 103a of the driven body 103, at least the protrusion 102c is subjected to a hardening process such as a quenching process in order to improve wear resistance. Has been.

  The piezoelectric element 102a, which is an electro-mechanical energy conversion element, is bonded to the elastic body 102b using an adhesive. The piezoelectric element 102a has a structure in which electrodes having a predetermined shape are formed on both sides of a rectangular plate-shaped piezoelectric ceramic. A drive voltage (AC voltage) having a predetermined frequency is applied to the electrode of the piezoelectric element 102a via a flexible wiring board (not shown). As a result, vibrations of a first vibration mode and a second vibration mode, which will be described later, are excited on the vibrating body 102, and the protrusions are within the plane including the direction connecting the two protrusions 102c and the protrusion direction of the protrusions 102c. An elliptical motion can be generated in 102c. The driven body 103 is frictionally driven by the elliptical motion of the protrusion 102c, and the driven body 103 and the vibrating body 102 can be relatively moved in the X direction. In the present embodiment, as will be described later, since the vibrating body 102 is supported by the support member 104 and cannot move in the X direction, the driven body 103 moves in the X direction. Note that the X direction is an axial direction (a direction in which the axis extends) of a third axis that is substantially orthogonal to both the first rotation axis L1 and the second rotation axis L2.

  The driven body 103 is made of a metal material such as stainless steel and has a substantially round bar shape. In the driven body 103, a sliding portion 103a which is a friction sliding surface with the two protrusions 102c of the vibrating body 102 is formed in a flat shape, and is connected to the universal joint 105 at one end in the longitudinal direction. A portion 103b is provided. The sliding portion 103a can be formed by flattening the side surface (curved surface) of the round bar-like member by pressing or cutting, and performing lapping or the like so as to be a smooth surface. Further, the sliding portion 103a is subjected to a hardening process such as a nitriding process, so that the wear resistance is enhanced. The vibrating body 102 and the driven body 103 are formed with a predetermined pressure by a magnetic force (attraction force) generated by a magnet such as a neodymium magnet or a ferrite magnet (not shown) provided in the driven body 103 or the like. It is in pressure contact with the vibrating body 102 (projection 102c) in the direction.

  The support member 104 includes a support portion 104a and a guide groove portion 104b, and the fixing portion 102d of the vibrating body 102 is joined to the support portion 104a by welding, adhesion, or the like. The support portion 104a has a shape protruding in the Z direction, and stably fixes only the fixing portion 102d of the vibrating body 102 having a small vibration amplitude. Accordingly, propagation of vibration excited by the vibrating body 102 to the base portion 130 can be suppressed, and excitation of vibration in the vibrating body 102 is inhibited by fixing the vibrating body 102 to the support member 104. Can be suppressed.

  The guide groove 104b of the support member 104 is located in the middle of the two protrusions 102c in the X direction, and has a long hole shape extending substantially parallel to the Y direction. A guide pin 132 formed so as to protrude in the Z direction on the base portion 130 is inserted into the guide groove portion 104b. The outer diameter of the guide pin 132 and the width of the guide groove portion 104b in the X direction are dimensional tolerances (fitting tolerances) that allow the support member 104 to move in the Y direction but not in the X direction with respect to the guide pin 132. Is set to Therefore, the support member 104 is restricted from moving in the X direction by the guide pins 132, but can move in the Y direction and the Z direction. Therefore, the vibrating body 102 joined to the support member 104 is also movable in the Y direction and the Z direction while being restricted from moving in the X direction with respect to the base portion 130. The reason for the configuration will be described later.

  The universal joint 105 is a so-called universal joint, and has a structure that can rotate around the Y axis and the Z axis in the top part 105b. A mounting hole 105 a is provided at each longitudinal end of the universal joint 105. One mounting hole 105 a is fitted to a connecting portion 103 b provided in the driven body 103, whereby the universal joint 105 is connected to the driven body 103. The other attachment hole 105 a of the universal joint 105 is fixed to the attachment portion 112 of the camera body 110. Thus, the mounting portion 112 of the camera body 110 and the driven body 103 are connected via the universal joint 105. The connection between the universal joint 105 and the driven body 103 or the mounting portion 112 may be performed using adhesion, shrink fitting, a pin, or the like.

  Next, the natural vibration mode used for driving the vibration type actuator 101a (driving the driven body 103 in the X direction) will be described. FIG. 3B is a perspective view illustrating a first vibration mode in which the vibrating body 102 is excited to drive the vibration type actuator 101a. FIG. 3C is a perspective view illustrating a second vibration mode in which the vibrating body 102 is excited to drive the vibration type actuator 101a. In FIGS. 3B and 3C, in order to facilitate understanding of the deformed shape, the displacement amount is enlarged and displayed as compared with the shape of the vibrating body 102. The X, Y, and Z directions shown in FIGS. 3B and 3C are the same as the X, Y, and Z directions in FIGS. 2 and 3A, respectively.

  The first vibration mode is a mode in which secondary bending vibration is generated in the X direction, and has three nodes substantially parallel to the Y direction. The protrusion 102c is driven in the X direction by the vibration of the first vibration mode. Reciprocate at At this time, the protrusion 102c can be greatly displaced in the X direction by providing the protrusion 102c in the vicinity of a position that becomes a node by vibration in the first vibration mode. The second vibration mode is a mode in which a primary bending vibration is generated in the Y direction, has two nodes substantially parallel to the X direction, and the protrusion 102c is in the Z direction due to the vibration of the second vibration mode. Reciprocate at At this time, the protrusion 102c can be greatly displaced in the Z direction by providing the protrusion 102c in the vicinity of the position where the protrusion 102c becomes antinode due to the vibration in the second vibration mode. Note that the fixing portion 102d of the vibrating body 102 is fixed to the support portion 104a in the vicinity of the node where the vibration amplitude of the first vibration mode is small and in the vicinity of the node where the vibration amplitude of the second vibration mode is small. Has been.

  By combining the first vibration mode and the second vibration mode, an elliptical motion is generated in the substantially ZX plane at the tip of the projection 102c, and thereby the driven body 103 is frictionally driven in the approximately X direction. A driving force can be generated. At this time, the two protrusions 102c are provided at the nodes of the first vibration mode and the antinodes of the second vibration mode, respectively, so that the vibration displacement of the protrusion 102c is maximized. Therefore, high output can be obtained.

  Next, a driving method of the vibration type actuators 101a and 101b when the surveillance camera 100 performs tilt driving and pan driving will be described. Here, for convenience, a case where only the tilt angle is set to ± 30 degrees and a case where only the pan angle is set to ± 30 degrees will be described, but the tilt angle and the pan angle are not limited thereto. The state of the surveillance camera 100 when the pan angle and the tilt angle are 0 degrees (when in the home position) in the surveillance camera 100 is shown in FIGS.

  FIG. 4 is a perspective view showing a state in which the surveillance camera 100 is tilt-driven. FIG. 4A shows a state of the monitoring camera 100 driven from the home position by only −30 degrees from the tilt angle. When the driven bodies 103 of the vibration type actuators 101a and 101b are driven by the same movement amount in the direction of the arrow M2, which is a positive direction in the X direction, the two attachment portions 112 of the camera body 110 are respectively driven bodies. A force is received from 103 in the direction of the arrow M2. Since the attachment portion 112 is separated from the first rotation axis L1 by a certain distance, the force in the direction of the arrow M2 acts on the attachment portion 112 as a moment around the first rotation axis L1. On the other hand, as described above, when the surveillance camera 100 in the home position is viewed from the X direction, the two attachment portions 112 are provided at positions that are substantially symmetrical in the Y direction about the second rotation axis L2. ing. Therefore, the moments around the second rotation axis L2 due to the force in the direction of the arrow M2 acting on the two attachment portions 112 cancel each other, and thus the revolving frame 120 does not rotate around the second rotation axis L2. . Therefore, by simultaneously driving the two driven bodies 103 in the direction of the arrow M2 with the same movement amount, the camera body 110 is rotated about the first rotation axis L1, and the camera as shown in FIG. The main body 110 can be in a state where only the tilt angle is −30 degrees.

  While the tilt angle changes from 0 degree to -30 degrees, the top part 105b of the universal joint 105 rotates around the Y axis, and the attachment part 112 moves in the positive direction in the X direction along with this, It rotates around the first rotation axis L1 so as to move in the positive direction. Here, since the vibrating body 102 is attracted to the driven body 103 by a magnetic force, the vibrating body 102 and the support member 104 are integrated with the base portion 130 as the camera body 110 is tilted. The guide pin 132 moves in the protruding direction (positive direction in the Z direction). At this time, since the movement of the support member 104 in the X direction is restricted, the driving of the vibration type actuators 101a and 101b is maintained in a stable state.

  FIG. 4B shows a state of the surveillance camera 100 in which only the tilt angle is driven +30 degrees from the home position. When the driven bodies 103 of the vibration type actuators 101a and 101b are driven by the same amount of movement in the direction of the arrow M1, which is the negative direction of the X direction, the two attachment portions 112 of the camera body 110 are respectively driven bodies. A force is received from 103 in the direction of the arrow M1. At this time, the moment around the first rotation axis L1 acts on the camera body 110 as in the case of the tilt drive with the tilt angle set to −30 degrees, but the revolving frame 120 is subjected to the second rotation. No moment is generated around the axis L2. Therefore, by simultaneously driving the two driven bodies 103 in the direction of the arrow M1 with the same movement amount, the camera body 110 is rotated about the first rotation axis L1, and the camera as shown in FIG. The main body 110 can be in a state where only the tilt angle is +30 degrees.

  While the tilt angle changes from 0 degree to +30 degrees, the top part 105b of the universal joint 105 rotates around the Y axis, and the attachment part 112 moves in the negative direction in the X direction while moving in the positive direction in the Z direction. To rotate around the first rotation axis L1. Therefore, as in the case where the tilt angle is driven to be −30 degrees, the support member 104 and the vibrating body 102 move integrally in the positive direction of the Z direction as the camera body 110 is driven to tilt.

  FIG. 5 is a perspective view showing a state in which the surveillance camera 100 is pan-driven. FIG. 5A shows a state of the surveillance camera 100 that is driven only by -30 degrees pan angle from the home position. One vibration type actuator 101a is driven so that the driven body 103 moves in the direction of the arrow M1 (the negative direction of the X direction). Further, the other vibration type actuator 101b is driven so that the driven body 103 moves in the direction of the arrow M2 (the positive direction of the X direction). Then, the two attachment portions 112 of the camera body 110 receive the forces in the directions of the arrows M1 and M2 from the driven bodies 103 of the vibration type actuators 101a and 101b, respectively. The force acting on the two attachment portions 112 in this way becomes a moment for rotationally driving the camera body 110 and the turning frame body 120 around the second rotation axis L2, but the moments canceling each other around the first rotation axis L1. It becomes. Therefore, by driving the driven bodies 103 of the vibration type actuators 101a and 101b by the same amount of movement in the directions of the arrows M1 and M2, as shown in FIG. It can be in a state of 30 degrees.

  In addition, while the pan angle changes from 0 degree to −30 degrees, the top part 105b of the universal joint 105 rotates around the Z axis. The driven body 103 of the vibration type actuator 101a moves in the Y direction in the positive direction, and the driven body 103 of the vibration type actuator 101b moves in the Y direction in the negative direction. Here, the vibrating body 102 is attracted to the driven body 103 by a magnetic force, and the support members 104 of the vibration type actuators 101 a and 101 b are movable in the Y direction with respect to the base portion 130. Therefore, with the pan driving of the camera body 110, the vibrating body 102 and the support member 104 move together so as to approach each other in the Y direction. At this time, since the movement of the support member 104 in the X direction is restricted, the driving of the vibration type actuators 101a and 101b is maintained in a stable state.

  FIG. 5B shows a state of the monitoring camera 100 in which only the pan angle is driven +30 degrees from the home position. When only the pan angle is driven by +30 degrees, the direction of driving the driven bodies 103 of the vibration type actuators 101a and 101b may be reversed from the case where only the pan angle is driven by -30 degrees. That is, the driven body 103 of the vibration type actuator 101a may be driven in the direction of the arrow M2 and the driven body 103 of the vibration type actuator 101b may be driven in the direction of the arrow M1 by the same movement amount. Thereby, as shown in FIG.5 (b), the camera main body 110 can be made into the state which only the pan angle became +30 degree | times. While the pan angle changes from 0 degree to +30 degrees, the top part 105b of the universal joint 105 rotates around the Z axis so that the driven bodies 103 of the vibration type actuators 101a and 101b approach each other in the Y direction. Move to. Accordingly, the vibrating body 102 and the support member 104 move together so as to approach each other in the Y direction.

  As described with reference to FIG. 4, in the surveillance camera 100, only the tilt drive is realized by driving the driven bodies 103 of the vibration actuators 101a and 101b in the same direction in the X direction by the same movement amount. be able to. As described with reference to FIG. 5, in the surveillance camera 100, only the pan driving is performed by driving the driven bodies 103 of the vibration type actuators 101 a and 101 b in the opposite directions in the X direction by the same movement amount. Can be realized. The drive mode of the monitoring camera 100 is not limited to the drive that executes the tilt drive and the pan drive independently as described above. That is, by adjusting the amount and direction of movement of the driven body 103 of each of the vibration type actuators 101a and 101b, pan driving and tilt driving are realized simultaneously, and the optical axis L3 of the lens unit 111 is in a desired direction. It is possible to turn to.

  As described above, the surveillance camera 100 realizes tilt drive and pan drive of the camera body 110 by cooperative driving of the vibration type actuators 101a and 101b. That is, unlike the conventional surveillance camera, the other actuator is not rotated in the pan direction together with the camera body in accordance with the pan driving by one actuator. Therefore, a large torque is not required for the vibration type actuators 101a and 101b, so that the entire surveillance camera 100 can be downsized. In addition, since the inertia during pan driving can be reduced, controllability such as positioning (angle adjustment) accuracy and responsiveness of the camera body 110 can be improved. Further, the torque shared by the vibration type actuators 101a and 101b during tilt driving and pan driving is substantially half that when tilt driving or pan driving is performed by one vibration type actuator. Therefore, the vibration type actuators 101a and 101b can be reduced in size as compared with the configuration in which the tilt drive and the pan drive are driven by different actuators, and thus the surveillance camera 100 can be further reduced in size.

  In the surveillance camera 100, since the vibration type actuators 101a and 101b operate in a coordinated manner without interfering with each other during tilt driving and pan driving, they have a conventional structure that rotationally drives a spherical driven body. It is not necessary to execute an operation for reducing the frictional force. Therefore, power required for driving the camera main body 110 only needs to be supplied to the vibrating bodies 102 (piezoelectric elements 102a) of the vibration type actuators 101a and 101b, so that power consumption can be suppressed. Further, in the monitoring camera 100, the vibration type actuators 101 a and 101 b have a small amount of movement in the Y direction and the Z direction during tilt driving and pan driving relative to the base unit 130. Therefore, it is not necessary to use a slip ring that is necessary for a configuration in which the vibration type actuator rotates around the pan drive axis by pan driving, and power can be supplied to the vibrating body 102 with a simple configuration using a flexible wiring board or the like. Thus, the surveillance camera 100 can be downsized. Furthermore, in the monitoring camera 100, a guide groove 104b is provided in the support member 104 that fixes the vibration body 102, and the vibration body 102 and the support member 104 can be moved integrally in the Y direction and the Z direction. As a result, the number of parts can be reduced compared to the case where a guide member is provided separately from the vibration type actuator, and as a result, the surveillance camera 100 can be reduced in size and weight.

  In the surveillance camera 100, since the sliding portion 103a of the driven body 103 constituting the vibration type actuators 101a and 101b has a flat shape, the driven body needs to be processed with high accuracy and complexity like a sphere. As a result, productivity can be improved and costs can be reduced. The surveillance camera 100 uses linear vibration actuators 101a and 101b that drive the driven member 103 in the X direction. Therefore, the structure can be simplified as compared with the case where the rotational output of a rotary motor such as a DC motor or a stepping motor is converted into a linear output using a ball screw, a gear, or the like. Can be reduced in weight. Since no ball screw or gear is used, backlash or the like does not occur, and the camera body 110 is directly driven, so that the camera body 110 can be positioned with high accuracy and controlled with high responsiveness. At this time, the surveillance camera 100 does not generate driving sound (meshing sound) such as a ball screw or a gear, so that a quiet operation is possible.

  The vibration type actuators 101a and 101b have a holding force because the driven body 103 is driven using a frictional force. Therefore, even if an unexpected external force acts on the monitoring camera 100 when no power is supplied to the vibrating body 102 (piezoelectric element 102a), it is possible to suppress the camera body 110 and the turning frame body 120 from moving. In particular, in the surveillance camera 100, two vibration type actuators 101 a and 101 b are connected to the camera body 110. For this reason, the holding force when an external force is applied only in one of the rotation directions of tilt rotation and pan rotation is twice that when one actuator is used for rotation in one direction. Has a high effect. Therefore, the monitoring camera 100 does not require a brake or the like that is necessary for the monitoring camera configured with a DC motor or the like as a drive source, thereby further reducing the size and weight of the entire apparatus.

  Here, a stage apparatus which is one of the modified examples of the monitoring camera 100 will be described. FIG. 6 is a perspective view showing a schematic configuration of the stage apparatus 200. The stage apparatus 200 includes vibration type actuators 201a and 201b, a stage 210, a turning frame body 220, and a base part 230. The stage apparatus 200 has a structure in which the camera body 110 of the monitoring camera 100 according to the first embodiment is replaced with a stage 210. Therefore, the vibration type actuators 201a and 201b, the turning frame body 220, and the base part 230 have the same structure as the vibration type actuators 101a and 101b, the turning frame body 120, and the base part 130, respectively. The description to be omitted is omitted.

  The stage 210 has a flat plate shape, and the surface thereof is provided with screw holes 214 at a plurality of locations. Driven members of various shapes and sizes can be attached to the stage 210 using the plurality of screw hole portions 214. Thereby, the versatility of the stage apparatus 200 can be improved. For example, the stage apparatus 200 can be used as a pan head for fixing an imaging apparatus such as a digital camera. In addition, if the stage apparatus 200 is used, even when the camera is attached to the stage 210 to be a surveillance camera, the direction of the optical axis of the camera can be changed according to the actual mounting position of the base unit 230. A surveillance camera can be realized according to the needs.

  By the way, in the surveillance camera 100, the universal joint 105 uses the piece 105 b that can rotate around the Y-axis and the Z-axis, but the connection structure of the mounting portion 112 of the camera body 110 and the driven body 103. Is not limited to this. For example, the universal joint 105 may be configured to be rotatable about the Y axis and movable in the Y direction, and the support member 104 may be configured to be rotatable about the Z axis and movable in the Z direction. That is, as long as pan driving and tilt driving can be performed independently, the connection between the mounting portion 112 of the camera body 110 and the vibration type actuators 101a and 101b may be configured with any degree of freedom. . The universal joint 105 is not limited to a universal joint, and may have a joint shape or a groove shape as long as a necessary degree of freedom is obtained.

  Further, in the surveillance camera 100, the vibrating body 102 and the support member 104 are integrally formed in the Y direction by the engagement between the guide pin 132 provided on the base portion 130 and the guide groove portion 104 b provided on the support member 104. It was movable in each direction of the Z direction. However, the present invention is not limited thereto, and the guide groove 104b is designed so that the support member 104 can move only in the Z direction, and the friction drive by the vibrating body 102 is always possible even if the driven body 103 moves in the Y direction. A configuration in which the width of the driven body 103 is widened may be adopted.

  Next, a second embodiment of the present invention will be described. FIG. 7A is a perspective view showing a schematic configuration of a monitoring camera 300 according to the second embodiment of the present invention. The monitoring camera 300 includes a camera main body 310 having vibration type actuators 301 a and 301 b, a lens unit 311, and a mounting unit 312, a turning frame 320, and a base unit 330. The camera body 310, the turning frame body 320, and the base unit 330 included in the monitoring camera 300 are the same as the camera body 110, the turning frame body 120, and the base unit 130 included in the monitoring camera 100 according to the first embodiment. These descriptions are omitted.

  FIG. 7B is an exploded perspective view showing a schematic configuration of the vibration type actuator 301a constituting the surveillance camera 300 and its peripheral portion. Since the vibration type actuators 301a and 301b have the same structure, the description of the vibration type actuator 301b is omitted. The vibration type actuator 301 a includes a vibration body 302 and a driven body 303. Since the vibrating body 302 is the same as the vibrating body 102 constituting the vibration type actuator 101a described in the first embodiment, the description thereof is omitted.

  The base portion 330 is provided with a support spring member 304 that supports the vibrating body 302. The support spring member 304 is provided with a support portion 304a having a shape protruding in the Z direction, and a fixing portion 302d (corresponding to the fixing portion 102d of the vibration body 102) provided on the vibration body 302 is supported. It is joined to the part 304a by welding or adhesion. Similar to the first embodiment, the vibration body 302 is fixed to the support spring member 304 by the fixing portion 302d having a small vibration amplitude, thereby suppressing the vibration excited by the vibration body 302 from being transmitted to the base portion 330. be able to. In addition, it is possible to prevent the vibration excitation in the vibrating body 302 from being inhibited by fixing the vibrating body 302 to the support spring member 304.

  The support spring member 304 is an elastic member designed in a shape having a spring constant that can be deformed in each of the Y direction and the Z direction but is difficult to deform in the X direction. Therefore, the vibrating body 302 coupled to the support spring member 304 is restricted from moving in the X direction with respect to the base 330, but can move in each direction of the Y direction and the Z direction. It has become.

  The attachment portion 312 of the camera body 310 (corresponding to the attachment portion 112 of the camera body 110) and the driven body 303 of the vibration type actuator 301a are connected via a spherical bearing 305 which is an example of a connection member. The spherical bearing 305 has a structure that can rotate around each of the Y axis and the Z axis in the drawing in the spherical portion 305b. A mounting screw portion 305a is joined to the spherical surface portion 305b, and the mounting screw portion 305a is fitted into a connecting screw hole portion 303b provided at one end of the driven body 303, whereby the spherical bearing 305 is fitted to the driven body 303. Connected to

  The driven body 303 includes a magnet 303c and a sliding plate 303a that becomes a friction sliding surface with the vibrating body 302, and a connecting screw hole portion 303b that is connected to the spherical bearing 305 is provided in the magnet 303c. . The sliding plate 303a is subjected to a hardening process such as a nitriding process in order to increase the wear resistance, and is bonded to the magnet 303c using an adhesive. The vibrating body 302 and the driven body 303 are in contact with each other with a predetermined pressure by the attractive force acting between the magnet 303c and the elastic body constituting the vibrating body 302 and the support spring member 304.

  Similar to the monitoring camera 100 according to the first embodiment, the monitoring camera 300 also drives the driven bodies 303 of the vibration type actuators 301a and 301b by a predetermined amount of movement in a predetermined direction in the X direction. Tilt drive and pan drive of the main body 310 are realized. The vibrating body 302 receives a force from the driven body 303 in the Z direction during tilt driving. At this time, the support spring member 304 is deformed in the Z direction with deformation in the X direction being suppressed. Thus, a stable contact state can be maintained between the vibrating body 302 and the driven body 303. In addition, the vibrating body 302 receives a force from the driven body 303 in the Y direction during pan driving. At this time, the support spring member 304 is deformed in the Y direction while deformation in the X direction is suppressed. Thus, a stable contact state can be maintained between the vibrating body 302 and the driven body 303. Therefore, the monitoring camera 300 has the same effect as the monitoring camera 100 according to the first embodiment.

  In the monitoring camera 300, the vibrating body 302 and the driven body 303 are brought into pressure contact with each other using the magnet 303c, but the method of bringing the vibrating body 302 and the driven body 303 into pressure contact is limited to this. Is not to be done. FIG. 8 is a diagram (side view) illustrating another schematic configuration in which the vibrating body 302 and the driven body 303 ′ are brought into pressure contact. In the example of FIG. 8, the vibrating body 302 and the driven body 303 ′ are brought into pressure contact using the pressure member 306. Here, no magnet is used for the driven body 303 ′ shown instead of the driven body 303. For example, the same material as that of the driven body 103 of the vibration type actuator 101a is used for the driven body 303 '. Therefore, the sliding plate 303a is not joined to the driven body 303'.

  The pressure member 306 includes a pressure spring 306a, a pressure receiving member 306b, and a driven portion 306c. The pressure spring 306a is a coil spring or the like, and has a spring constant that allows the vibrating body 302 and the driven body 303 'to contact with a predetermined pressure. The pressure receiving member 306b receives the pressure from the pressure spring 306a and presses the driven body 303 ′ against the vibrating body 302 via the driven portion 306c. The driven portion 306c that contacts the driven body 303 ′ is a spherical body and is rotatably supported by the pressure receiving member 306b. Therefore, no matter which direction the driven body 303 ′ moves, pressure can be continuously applied to the driven body 303 ′, and the cost can be reduced by not using a magnet.

  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 100,300 Surveillance camera 101a, 101b, 301a, 301b Vibrating actuator 102,302 Vibrating body 102a Piezoelectric element 102b Elastic body 102c Protrusion part 102d Fixing part 103,303 Driven body 104 Support member 104b Guide groove part 105 Universal joint 110,310 Camera body 120, 320 Revolving frame body 130, 330 Base portion 132 Guide pin 200 Stage device 304 Support spring member 305 Spherical bearing

Claims (12)

A first rotating body;
A second rotating body that rotatably supports the first rotating body around an axis of the first axis;
A base portion that rotatably supports the second rotating body around an axis of a second axis substantially orthogonal to the first axis;
Two vibration-type actuators disposed on the base part,
Each of the two vibration actuators is
A support member supported by the base part;
A vibrating body held by the support member;
A driven body driven in the axial direction of a third axis that is substantially orthogonal to both the first axis and the second axis by vibration excited by the vibrating body;
The driven bodies of the two vibration actuators are connected to the first rotating body,
When the driven bodies of the two vibration actuators are driven in the same direction in the axial direction of the third axis, the first rotating body rotates about the axis of the first axis,
When the driven bodies of the two vibration actuators are driven in directions opposite to the axial direction of the third shaft, the first rotating body and the second rotating body are integrally formed with the second Rotation drive device characterized by rotating around the axis of the shaft.   The driven bodies of the two vibration-type actuators are respectively connected to the first via a connecting member that can rotate about an axis parallel to the first axis and an axis parallel to the second axis. The swivel drive device according to claim 1, wherein the swivel drive device is connected to the rotating body.   The turning drive device according to claim 2, wherein the connecting member is a universal joint or a spherical bearing.   The driven bodies of the two vibration actuators are coupled to the first rotating body via the coupling member at a position away from the first axis in the axial direction of the second axis. The turning drive device according to claim 2 or 3, characterized in that.   The driven bodies of the two vibration actuators are arranged at positions symmetrical with respect to the second axis in the axial direction of the first axis when viewed from the axial direction of the third axis. The turning drive device according to any one of claims 1 to 4, wherein the turning drive device is provided. Each of the vibration bodies of the two vibration actuators has a protrusion that is in pressure contact with the driven body,
The driven body is moved in the axial direction of the third axis by driving the vibrating body so that an elliptical motion is generated in a plane substantially orthogonal to the first axis at the protrusion. The turning drive device according to any one of claims 1 to 5.   In the vibration type actuator, the tip of the protruding portion of the vibrating body and the driven body are in pressure contact with each other in the protruding direction of the protruding portion by an attractive force of a magnet provided on the driven body. The turning drive device according to claim 6, wherein the turning drive device is provided. A support member fixed to the vibrating body of the vibration type actuator;
The support member is movable in the axial directions of the first shaft and the second shaft, and is supported by the base portion so that movement is restricted in the axial direction of the third shaft. The turning drive device according to claim 6, wherein the turning drive device is provided. The support member has an elongated hole-shaped guide groove extending in a direction parallel to the axial direction of the first shaft,
9. The turning drive device according to claim 8, wherein the base portion has a guide pin that protrudes in the axial direction of the second shaft and is inserted into the guide groove portion.   9. The turning drive device according to claim 8, wherein the support member is an elastic member that can be deformed in the respective directions of the first shaft and the second shaft with respect to the base portion.   The turning drive device according to any one of claims 1 to 10, wherein the first rotating body is a flat stage.   The turning drive device according to claim 1, wherein the first rotating body is an imaging device.