JP2009205704A - Actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an actuator capable of adjusting the direction of a control object in high accuracy, having a low consumption and excelling in response performance. <P>SOLUTION: The actuator comprises a control object 20 provided on the side of movable part, a support shaft 44 on which the control object 20 is provided, a support mechanism 50 provided on the side of a stationary part and supporting the support shaft 44 so as to freely swing with respect to a predetermined reference axis O1-O1, a drive mechanism 40 for providing a drive force to swing the support shaft 44 so that its posture tilts from neutral position where the support shaft 44 coincides with the reference axis, and restoring members 52, 54 for providing an urging force to return the support shaft 44 to the neutral position. further, the support mechanism 50 includes a plurality of small balls 51a, and an end 44a of the support shaft 44 is supported by the small balls 51a. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a biaxial actuator capable of adjusting a tilt angle of a mirror to a desired angle, for example.

  As a method for recording or reproducing a two-dimensional digital signal in a multiplexed manner on a holographic recording medium, a method in which the incident angle or wavelength of reference light incident on the recording medium is changed is generally used. As a conventional actuator for adjusting the incident angle of the light beam (reference light), a galvanometer mirror is representative (for example, Patent Document 1).

Patent Document 1 is a biaxial planar type galvanometer mirror formed by using a semiconductor manufacturing technique. In this galvanometer mirror, the outer frame is supported by the first torsion bar that forms one axis with respect to the support, and the inner frame that includes the mirror with respect to the outer frame forms the second axis. Supported by a torsion bar. When electromagnetic force is generated in the magnetic drive unit, torsional deformation occurs around the first torsion bar and the second torsion bar arranged orthogonal to each other, so that the outer frame and the inner frame are respectively seesaw-shaped. By tilting the mirror, the angle of the mirror can be freely changed.
Japanese Unexamined Patent Publication No. 2004-271821 (Page 6, FIGS. 8 to 9)

  However, since the galvanometer mirror supporting means described in Patent Document 1 is a so-called gimbal mechanism, there are the following problems.

  (1) The gimbal mechanism has a configuration in which the inner frame and the outer frame are independently rotated by torsional deformation of the first and second torsion bars, but the support center point of the mirror to be controlled is The center of one torsion bar coincides with the center of the second torsion bar. The point at which the two centers coincide (support center point) largely depends on the accuracy of the individual gimbal mechanism, but since it is a configuration that uses torsional deformation, the support center point is likely to vary for each gimbal mechanism, It was difficult to set a single point in terms of mechanism. When scanning the hologram recording medium by shaking the reference light while changing the angle of the mirror, the support center point becomes the center of the angle scan, but if the support center point is uncertain as described above, There is a problem that a read error occurs.

  (2) The gimbal mechanism has a structurally large moment of inertia of the outer frame and the inner frame. For this reason, when external vibration or the like occurs, the outer frame and the inner frame constituting the galvano mirror are likely to swing. When the oscillation described above occurs, the support center point in the gimbal mechanism fluctuates, which makes it difficult to irradiate the holographic recording medium with a light beam at a desired angle. Occurs.

  (3) Since the torsional deformation in the gimbal mechanism acts as a resistance when the outer frame and the inner frame are rotated, it is necessary to generate a magnetic force larger than the resistance at the start of the deformation. For this reason, it is necessary to flow a large current through the coil at the start of driving, and power consumption tends to increase. In addition, a time lag occurs at a small current, and there is a problem that the mirror angle is changed quickly, that is, the response is dull.

  The present invention is for solving the above-described conventional problems, and the central portion (support center point) at the time of angle scanning can be determined to a certain point, and the control target is centered on the support center point. An object of the present invention is to provide an actuator capable of adjusting the angle of a mirror.

  Further, the present invention provides an actuator capable of suppressing the fluctuation of the support center point (virtual angle scan center portion) of the mirror to be controlled even if external vibration occurs, and adjusting the direction of the control object with high accuracy. It is an object.

  Another object of the present invention is to provide an actuator that reduces resistance that hinders the change of the angle, has low power consumption, and is excellent in responsiveness.

The present invention provides a control object provided on the movable part side, a support shaft provided with the control object, and a support provided on the fixed part side and swingably supported with respect to a predetermined reference axis. A mechanism, a drive mechanism that applies a driving force that swings the support shaft in a posture inclined from a neutral position that coincides with the reference axis, and a return member that applies a biasing force that returns the support shaft to the neutral position. ,
The support mechanism includes a plurality of small spheres arranged in a ring shape, and the tips of the support shafts are supported by the plurality of small spheres.

  In the present invention, instead of the conventional gimbal mechanism, the support shaft and the pivot bearing that supports the tip of the support shaft with a plurality of small spheres are used, so the support center point of the controlled object (mirror) is determined as one point on the mechanism. Can do. In addition, even if the support shaft swings, the variation of the support center point can be reduced. For this reason, the direction of the controlled object can be adjusted with high accuracy. Therefore, when it is used for a galvanometer mirror in a holographic reproducing device, it becomes easy to irradiate a light beam to a holographic recording medium at a desired angle, and a reading error based on a change in a support center point as in the conventional case is avoided. The frequency of occurrence can be reduced.

  Further, the sliding friction at the portion where the tip of the support shaft and the small sphere contact is extremely small. For this reason, it can be driven quickly with a small current. That is, an actuator with low power consumption and quick response can be obtained.

  For example, the return member is provided between a leaf spring provided on the fixed portion side, and between the leaf spring and the control target, and is pulled by the urging force of the leaf spring so that the support shaft is moved to the plurality of support shafts. It is comprised as an erection member pressed against a small ball.

  In this case, the installation member is a plurality of deformable wires or a plurality of sticks formed as a rigid body.

  Alternatively, the return member is a plurality of coil springs that are stretched between the fixed portion and the control target and press the tips of the support shafts against the plurality of small balls.

  With the above-described means, the support center point can be set to one point with a simple configuration. In addition, the fluctuation of the support center point after the support shaft swings can be suppressed to a small value.

  In the above, the drive mechanism can be configured to be driven by an electromagnetic force generated by the current flowing in the coil and the magnetic field of the permanent magnet.

With the above means, the drive mechanism can be configured easily.
In the above, it is preferable that the support shaft is provided with a rotation suppressing member.

  With the above means, the swinging motion of the support shaft can be allowed and the rotational motion around the shaft can be restricted. For this reason, in particular, even if a large external force that causes the support shaft to rotate about the axis is generated, the support shaft does not rotate. Therefore, the tilt angle of the control target can always be set to a desired angle. Become.

  For example, the rotation suppressing member connects the fixing ring provided on the outermost peripheral portion, the driving ring provided on the inner side thereof, the restraining ring provided on the innermost peripheral portion, and the fixing ring and the driving ring. A first connecting part, a second connecting part for connecting the drive ring and the restraining ring, the fixing ring is fixed to the fixing part side, and the support shaft is at the center of the restraining ring. Can be configured as fixed.

  In this case, both the first connecting portion and the second connecting portion are formed by a pair of bellows, and the pair of bellows forming the first connecting portion and the second connecting portion are formed. It is preferable that the pair of bellows are provided at positions different from each other by 90 degrees.

  Alternatively, the rotation suppressing member can be deformed in a pair of deformable members having a deformable portion deformable in a first direction and in a second direction orthogonal to the first direction and the pair of deformable members. A connecting member that connects the connecting members, and a connecting ring provided on the connecting member, wherein both ends of the pair of deformable members are fixed to the fixed portion side, and the support shaft is fixed to the center of the connecting ring Can be configured as

  In any of the above-mentioned means, on the one hand, the rotational movement in the direction around the axis can be restricted, and on the other hand, it is possible to allow the support shaft to fall (swing movement).

In the present invention, it is possible to provide an actuator capable of adjusting the direction of a controlled object with high accuracy.
In the present invention, an actuator having low power consumption and quick response can be obtained.

  1 is an exploded perspective view showing an actuator of the present invention, FIG. 2 is a sectional view of the actuator, FIG. 3 is a perspective view showing a magnetic field generating portion from the rear, FIG. 4 shows a coil portion, and A is a plane of the coil portion. FIGS. 5A and 5B are cross-sectional views taken along line B-B of FIG. 5A, FIG. 5 is a cross-sectional view similar to FIG. 2 illustrating the operating state of the actuator, and FIG. FIG.

  The actuator shown in FIGS. 1 and 2 is mounted on, for example, a holographic reproducing device. In the holographic reproducing device, a biaxial type for tilting a reflecting mirror in a predetermined direction when reflecting a light beam (reference light) emitted from a laser light source and irradiating the holographic recording medium at a desired angle. Used as a galvanometer mirror.

  As shown in FIGS. 1 and 2, the actuator 10 shown in the present embodiment includes a mirror unit 20, a magnetic drive unit 40, a support mechanism unit 50, and the like to be controlled.

  The mirror unit (control target) 20 includes a total reflection type mirror 21 and a stage 22 to which the mirror 21 is attached. A base 23 is integrally fixed to the surface of the stage 22 on the Z1 side. As shown in FIG. 2, the base 23 is provided so as to coincide with a predetermined reference axis O1-O1. The stage 22 is fixed so as to be inclined with respect to the base 23. For this reason, the reflecting surface 21a of the mirror 21 is not perpendicular to the reference axis O1-O1, but has a predetermined inclined posture. In the actuator 10, light incident at a predetermined angle with respect to an axis perpendicular to the reflecting surface 21a is emitted to the reflecting surface 21a at an angle symmetrical to the incident angle with respect to the axis. By changing the tilt angle of the mirror 21, the angle of the reflected light in the emission direction can be adjusted.

  The magnetic drive unit 40 has a magnetic field generation unit 41 that constitutes the movable part side and a coil part 45 that constitutes the fixed part side.

  As shown in FIG. 3, the magnetic field generator 41 has an upper yoke 42, a lower yoke 43, and a permanent magnet M. The upper yoke 42 is formed of, for example, an iron-based magnetic material. In this embodiment, the upper yoke 42 is formed as an octagonal metal plate wider than the area of the bottom surface of the permanent magnet M.

  As shown in FIGS. 2 and 3, a support shaft 44 extending in the Z2 direction is fixed to one surface (the surface on the Z2 side) of the upper yoke 42. A tip 44a of the support shaft 44 is formed in a conical shape. Note that the surface of the cone is preferably polished in a mirror shape so that sliding friction is reduced.

  The permanent magnet M has a cubic shape, for example, and is fixed to the center of the upper yoke 42. A through hole M1 is formed at the center of the permanent magnet M along the direction of the reference axis O1-O1. The support shaft 44 is inserted into the through hole M1. The permanent magnet M may be a ring having a hole in the center.

  As shown in FIG. 1, the other yoke (Z1 side) surface of the upper yoke 42 is provided with a slightly raised mounting portion 42a, and a positioning convex portion 42b that coincides with the reference axis O1-O1 at the center thereof. Is formed. The mounting portion 42a and the positioning convex portion 42b are mounted in a state where the end portion of the base portion 23 of the stage 22 is positioned.

  The lower yoke 43 is formed of a metal plate made of an iron-based magnetic material. As shown in FIG. 3, the lower yoke 43 includes a base portion 43A having a quadrangular shape and arm portions 43a and 43a extending from the base portion 43A in a cross direction (a direction perpendicular to the reference axis O1-O1). , 43a, 43a.

  A through hole 43b is formed at the center of the base portion 43A, the support shaft 44 is inserted through the through hole 43b, and the tip of the support shaft 44 protrudes in the Z2 direction.

  The middle part of the four arms 43a, 43a, 43a, 43a is bent in the direction close to the upper yoke 42 (Z1 direction), and the tip is bent so as to face the surface of the upper yoke 42 in parallel. Has been. Then, a gap g is formed at a portion where each tip of each arm portion 43a of the lower yoke 43 and the upper yoke 42 face each other.

  In other words, the upper yoke 42 is provided with a control object constituting the mirror part 20 fixed on one surface (Z1 side) thereof, and a magnetic field generator 41 constituting the movable part side provided on the other surface (Z2 side). ing.

  As shown in FIG. 2, the permanent magnet M is magnetized, for example, on the lower yoke 43 side as an N pole and on the upper yoke 42 side as an S pole. Magnetic paths are formed inside the upper yoke 42 and the lower yoke 43, and a magnetic field is formed in each gap g.

  As shown in FIG. 4A, the coil portion 45 is formed of a resin material or the like, and has a bobbin 46 formed in a substantially cross shape in plan view. The bobbin 46 has a square frame portion 46A provided at the center, and four cylindrical winding support portions 46B, 46B, 46B and 46B that protrude in four directions from the outer peripheral surface of the frame portion 46A. is doing. A space is formed in the frame portion 46A, and communication portions 46a and 46a that are continuous with the space in the frame portion 46A and open in the Z1 direction are formed in the winding support portions 46B, 46B, 46B, and 46B. , 46a, 46a are formed. Further, flanges 46b, 46b, 46b, 46b are formed integrally with the ends of the respective winding support portions 46B so as to spread in the direction perpendicular to the four directions in which the respective winding support portions 46B extend. Coils C1, C2, C3, and C4 are wound around the outer periphery of each winding support portion 46B and between the outer peripheral surface of the frame portion 46A and the flange portion 46b. The bobbin 46 is fixed to a fixing member 49 (see FIG. 2) constituting the fixing portion side.

  The lower yoke 43 is disposed inside the bobbin 46. That is, the main body portion 43A of the lower yoke 43 is provided in the internal space of the frame portion 46A of the bobbin 46, and the arm portions 43a are disposed in the communication portions 46a of the winding support portions 46B. The tips of the arm portions 43a, 43a, 43a, 43a are opposed to the upper yoke 42 in a state where there is a movement margin in each of the coils C1, C2, C3, C4. In this state, the coils C1, C2, C3, and C4 are disposed in the gaps g.

  As shown in FIG. 4A, the coil C1 and the coil C2 are arranged in an axially symmetric position around the support shaft 44 (or the reference axis O1-O1), and the coil C3 and the coil C4 are also axially symmetric. It is arranged at the position. The coil C1, the coil C2, the coil C3, and the coil C4 are disposed at positions that differ by 90 degrees around the support shaft 44 (or the reference axis O1-O1).

  The coil C1 and the coil C2 are connected in series. Similarly, the coil C3 and the coil C4 are also connected in series. The coils C1 and C2 form a first magnetic drive unit, and the coils C3 and C4 form a second magnetic drive unit.

  As shown in FIG. 2, the support mechanism 50 is provided on the fixing member 49. The support mechanism unit 50 includes a pivot ball bearing 51, a pressurizing spring 52 formed of a leaf spring, and a wire (erection member) 54 that can be easily bent and deformed.

  The pivot ball bearing 51 includes a housing 51A having a substantially cylindrical shape and a plurality of small balls 51a arranged in a ring shape along the circumferential direction inside the housing 51A. An opening 51B is formed at the center of both surfaces of the housing 51A, and a part of the plurality of small balls 51a is exposed from the opening 51B. The surface of each small sphere 51a is polished in a mirror shape, and its sliding frictional resistance is extremely small.

  As shown in FIG. 1, the pressurizing spring 52 is formed in a substantially cross shape and has urging arms 52a, 52a, 52a, 52a extending from the main body 52A in four directions. Each of the urging arms 52a is in an elastically deformable state in the plate thickness (Z) direction, and the distal end portion is bent in the Z1 direction approaching the magnetic field generating unit 41 from the main body portion 52A.

  As shown in FIG. 2, the main body 52 </ b> A of the pressurizing spring 52 is fixed to the fixing member 49. For this reason, the front-end | tip part of each urging | biasing arm 52a is lifted from the main-body part 52A, and it can be elastically deformed in this state.

  In the pivot ball bearing 51, the housing 51A is fixed on the main body 52A of the pressurizing spring 52. A plurality of small balls 51a constituting the pivot ball bearing 51 are arranged around the reference axis O1-O1. The tip 44 a of the support shaft 44 is inserted into the opening 51 B of the pivot ball bearing 51.

  As shown in FIG. 1, there are four wires (erection members) 54 between the tips of the urging arms 52a, 52a, 52a, 52a and the Z2 side surface of the upper yoke 42 facing the urging arms 52a, 52a, 52a, 52a. 54, 54 and 54 are installed in a tensioned state. That is, in a state where the urging arm 52a is elastically deformed in a direction approaching the upper yoke 42, the wires 54, 54, 54, 54 are formed between the tip of each urging arm 52a and the surface of the upper yoke 42 on the Z2 side. It is built between. Therefore, in the neutral position where the center of the support shaft 44 shown in FIG. 2 coincides with the reference axis O1-O1, the urging arms 52a, 52a, 52a, 52a are connected to the wires 54, 54, 54, 54. Thus, the upper yoke 42 is always pulled in a direction (Z2 direction) closer to the fixing member 49. For this reason, the mirror part 20 and the magnetic field generating part 41 that are provided on the upper yoke 42 and that constitute the movable part side are drawn in the Z2 direction shown in the drawing, which approaches the fixed member 49.

  As shown in FIG. 1, in the neutral position, the tip 44a of the support shaft 44 coincides with the reference axis O1-O1. And the said front-end | tip 44a is inserted in the center part (center part of the pivot ball bearing 51) of the some small ball 51a arrange | positioned in the said circumferential direction. At this time, the conical surface formed at the tip 44a of the support shaft 44 abuts each small sphere 51a, and each small sphere 51a is in the outer circumferential direction away from the Z2 direction and the central portion (reference axis O1-O1). Press on. However, the allowable amount that each small ball 51a can move in the outer peripheral direction in the housing 51A is small. For this reason, the tip 44 a of the support shaft 44 is pushed back in the central direction by a reaction against the pressing in the outer circumferential direction, and the support shaft 44 is supported by the plurality of small balls 51 a of the pivot ball bearing 51. Yes. That is, the pressurizing spring 52 and the four wires 54 function as a return member that returns the support shaft 44 to a neutral position (see FIG. 2) that coincides with the reference axis O1-O1. It should be noted that the frictional resistance of the portion where the conical surface forming the tip 44a is in contact with each small ball 51a is extremely small.

  The center point of a plurality of contact points where the surface of the cone forming the tip 44a of the support shaft 44 and each small ball 51a contact each other corresponds to the support center point (virtual angle scan center) O of the actuator 10. is doing. The actuator 10 can tilt around the support center point O.

Next, the operation of the actuator will be described.
When the drive current flowing through the coils C1, C2, C3, and C4 is zero, no electromagnetic force is generated in the magnetic drive unit 40. For this reason, the return shaft sets the support shaft 44 to a neutral position where the shaft center coincides with the reference axis O1-O1 (see FIG. 2).

  On the other hand, if a current in the counterclockwise direction when viewed from the outer direction indicated by the arrow A1 in FIG. 2 flows through the coil C1 forming the first magnetic drive unit, an electromagnetic force F1 ′ according to Fleming's left-hand rule is generated. appear. At the same time, an electromagnetic force F2 'is generated when a current flowing in the clockwise direction as viewed from the outer direction indicated by an arrow A2 in FIG. 1 flows through the coil C2 forming the first magnetic drive unit. The electromagnetic force F <b> 1 ′ and the electromagnetic force F <b> 2 ′ are equal in magnitude and direction, and are generated at the same position from the support center point O.

  However, since the coil portion 45 is fixed to the fixing member 49 side, the coil portion 45 is not movable. For this reason, the arm portions 43a and 43a disposed in the coils C1 and C2 have a reaction against the electromagnetic force F1 ′ and the electromagnetic force F2 ′ as a reaction between the electromagnetic force F1 ′ and the electromagnetic force F2 ′. A force F1 and a force F2 that are equal in magnitude but opposite in direction are generated.

  The forces F1 and F2 can be divided into a radial component of a predetermined circle whose center of rotation is the support center point O and tangential components F1t and F2t, of which a tangential component F1t, F2t contributes as a force that causes rotation in the α1 direction in FIG.

  Therefore, as shown in FIG. 5, the support shaft 44, the magnetic field generator 41 supported on the support shaft 44, and the mirror portion 21 as a whole are centered on the support center point O and the reference axis O <b> 1-. It can be tilted from the neutral position coinciding with O1 in the direction of the coil C1 (α1 direction). Therefore, in FIG. 5, the inclination angle θ of the reflection surface 21 a of the mirror 21 that constitutes the control target 20 can be changed in the increasing direction.

  Furthermore, if the direction of the drive current passed through the coils C1 and C2 is changed, the directions of the forces F1 and F2 can be changed in the opposite directions. For this reason, the inclination angle θ of the reflection surface 21a of the mirror 21 can be tilted in the direction (α2 direction) to be reduced contrary to the above.

  That is, in the present invention, the center point of a plurality of contact points where the conical surface at the tip of the support shaft 44 contacts each small ball 51 a can be determined as the support center point O of the actuator 10.

  As described above, the surface of the tip 44a (conical surface) and the surface of the small sphere 51a are both polished in a mirror shape. For this reason, the sliding friction resistance in the contact part between both is in a very small state. Therefore, when starting the control object 20, the support shaft 44 can be smoothly tilted without applying large driving power. In addition, it is possible to start quickly with a small drive current. That is, according to the present invention, an actuator with low power consumption and excellent response can be obtained.

  As shown in FIG. 5, when the base portion 23 is tilted in the counterclockwise direction (α1 direction), the left side of the reference axis O1-O1 has the upper yoke 42 and the pressurizing spring 52 provided at a position facing the upper yoke 42. Displacement occurs in a direction in which the facing distance to the urging arm 52a becomes shorter. For this reason, the tension | tensile_strength of the wire 54a located in the left side of the said reference axis O1-O1 becomes small. On the other hand, on the right side of the reference axis O1-O1, the upper yoke 42 is displaced in the direction in which the facing distance between the upper arm 42 and the urging arm 52a of the pressing spring 52 provided at a position facing the upper yoke 42 becomes longer. For this reason, the tension | tensile_strength of the wire 54b located in the right side of the said reference axis O1-O1 becomes large.

  When the driving current flowing through the coils C1 and C2 is interrupted from this state and the forces F1 and F2 are extinguished, the wire 54b is pulled by the biasing force of the biasing arm 52b of the pressurizing spring 52 on the side where the tension is large. Since the upper yoke 42 is pulled in the clockwise (α2) direction via the support shaft 44, the mirror part (control target) 20 and the magnetic field generation part 41 are brought to the original neutral position (dotted line position). Can be restored.

  The above relationship is the same between the coil C3 and the coil C4 forming the second magnetic drive unit. That is, by changing the direction of the drive current flowing through the coil C3 and the coil C4, the coil C3 and the coil C4 are moved from the neutral position where the support shaft 44 coincides with the reference axis O1-O1 with the support center point O as a fulcrum. It can be tilted along the line-up direction (direction perpendicular to the coils C1, C2).

  Therefore, if the drive current is changed simultaneously with respect to the coils C1 and C2 forming the first magnetic drive unit and the C3 and C4 forming the second magnetic drive unit while changing the magnitude of the drive current, the support shaft 44 is The support center point O can be swung (tilted) in all directions except the Z-axis (reference axis O1-O1) direction. For this reason, in the actuator of the present invention, the mirror unit (control target) 20 can be set in various directions.

  The support shaft 44 is configured such that the tip 44a is supported by the pivot ball bearing 51. However, when some external force is applied, the support shaft 44 is rotated around the axis of the support shaft 44 (around the reference axis O1-O1). Rotation may occur.

  As schematically shown in FIG. 6, in the actuator 10 according to the present invention, the pressurizing spring 52 is provided with four points of the upper yoke 42 forming the magnetic field generating portion 41 at intervals of 90 degrees around the support shaft 44. Further, it is configured to be pulled in the Z2 direction via four wires 54 (indicated as 54a, 54b, 54c, and 54d individually). For this reason, when rotation β occurs around the support shaft 44, the four wires 54a, 54b, 54c and 54d are twisted together in the same direction as the rotation β. Since the twist at this time acts as a resistance force for suppressing the rotation, the rotation around the support shaft 44 can be suppressed to some extent.

  However, when the external force is large, it is difficult to completely suppress the rotation around the support shaft 44 with only the four wires 54a, 54b, 54c and 54d.

  Therefore, hereinafter, means for effectively suppressing the rotation even when a large external force is generated will be described.

  FIG. 7 shows a plan view and a side view of the rotation suppressing member. FIG. 7A shows a state where the support shaft is in a neutral position, and FIG. 7B shows a state after the support shaft is swung. FIG. 8 is an enlarged schematic view showing a state in which twisting due to rotation occurs in the connecting portion constituting the rotation suppressing member.

  For example, as shown in FIG. 2, the rotation suppressing member 60 is fixed to a surface on the Z2 side of the bobbin 46 that forms the coil portion 45 on the fixed portion side. As shown in FIGS. 7A and 7B, the rotation suppressing member 60 shown in this embodiment is composed of three ring-shaped members having different diameters and two types of connecting portions that connect the three ring-shaped members. .

  The annular member includes a fixing ring 61 provided on the outermost peripheral portion, a drive ring 62 provided on the inner side thereof, and a restraining ring 63 provided on the innermost periphery. In the state shown in FIG. 7A, the fixing ring 61, the drive ring 62, and the restraining ring 63 are substantially concentric.

  The connecting portion includes a pair of first connecting portions 65 and 65 that connect the fixed ring 61 and the driving ring 62, and a second connecting portion 66 and 66 that connects the driving ring 62 and the restraining ring 63. And have. The first connecting portions 65 and 65 and the second connecting portions 66 and 66 are all formed as bellows.

  One first connecting portion 65 and the other first connecting portion 65 are formed at symmetrical positions (positions different by 180 degrees) about the reference axis O1-O1. Similarly, one second connecting portion 66 and the other second connecting portion 66 are formed at symmetrical positions (positions different by 180 degrees) around the reference axis O1-O1. The pair of first connecting portions 65 and 65 and the pair of second connecting portions 66 and 66 are formed at positions shifted by 90 degrees in the circumferential direction.

  A constraining ring 63 provided at the innermost periphery is supported by the drive ring 62 via the second connecting portions 66, 66, and the drive ring 62 is further connected to the fixed ring 61 via the first connecting portions 65, 65. It is supported. The rotation suppressing member 60 is integrally formed of, for example, synthetic resin.

  In the rotation suppressing member 60, a part of the fixing ring 61 is fixed to the coil portion 45 constituting the fixing portion side. The rotation suppressing member 60 may be provided on the fixed portion side, and may be fixed to a support portion (not shown) formed by bending a part of the fixed member 49, for example. May be.

  The support shaft 44 is inserted into the restraining ring 63, and the support shaft 44 is fixed to the restraining ring 63 with an adhesive or the like.

  When rotation around the support shaft 44 occurs, the restraining ring 63 fixed to the support shaft 44 also rotates together. At this time, the restraining ring 63 includes the pair of second connecting portions 66 and 66, the drive ring 62, the pair of first connecting portions 65 and 65, and the fixing ring 61 together in the direction around the axis. Gives rotational force to rotate.

  However, the fixing ring 61 provided on the outermost peripheral portion as described above is fixed to the fixing portion side. Therefore, when a force in the direction around the axis of the support shaft 44 is generated, excessive torsional deformation is applied to the pair of first connecting portions 65 and 65 and the pair of second connecting portions 66 and 66 as shown in FIG. Etc. occur. And the restoring force with respect to a deformation | transformation at this time acts as suppression force which blocks | prevents rotation around the said axis | shaft. For this reason, even if an external force in the direction around the axis is generated, rotation of the support shaft 44 in the direction around the axis can be substantially prevented.

  The pair of first connecting portions 65 and 65 and the pair of second connecting portions 66 and 66 are formed of bellows, and thus can be expanded and contracted to some extent.

  For this reason, as shown in FIG. 7B, when the support shaft 44 tilts, one of the pair of first connecting portions 65, 65 is contracted and the other is extended. Similarly, when the support shaft 44 is tilted in a direction perpendicular to FIG. 7B, one of the pair of first connecting portions 66, 66 is contracted and the other is expanded in the orthogonal direction. To work.

  For this reason, in this rotation suppression member 60, since the said restraining ring 63 can be moved to the direction in which the said support shaft 44 inclines, the rocking | fluctuation (tilt operation) of the said support shaft 44 is not prevented.

  That is, the rotation suppressing member 60 according to the present invention has a function of allowing the support shaft 44 to be tilted but suppressing the rotation about the axis.

The rotation suppressing member may have the following configuration.
9A and 9B show another embodiment of the rotation suppressing member, FIG. 9A shows a state where the support shaft is in a neutral position, and FIG. 9B shows a state where the support shaft is swung.

  The rotation suppression member 70 shown in FIG. 9 has a substantially H shape when viewed in a plan view, and includes a pair of deformation members 71 and 72 that extend in parallel, and a connecting member that connects the deformation member 71 and the deformation member 72. 73.

  At both ends of the deformable member 71 and the deformable member 72, bellows-shaped deformable portions 71a and 71b and deformable portions 72a and 72b are respectively provided. Non-deformable portions 71A and 72A each having a substantially T shape are provided between the deformable portion 71a and the deformable portion 71b and between the deformable portion 72a and the deformable portion 72b.

  The connecting member 73 is provided between the center of the non-deformable part 71A and the center of the non-deformable part 72A. Deformed portions 73a and 73b are also provided at both ends of the connecting member 73, and both ends of the deformed portions 73a and 73b are connected to the non-deformed portions 71A and 72A.

  Then, both ends of the deformable member 71 and the deformable member 72 are fixed to a fixing portion (not shown). A connecting ring 73A is provided between the deforming portion 73a and the deforming portion 73b, and the support shaft 44 is fixed to the center of the connecting ring 73A.

  As shown in FIG. 9B, in the rotation suppressing member 70, when an external force acts on the support shaft 44 in parallel with the first direction along the deformation member 71 and the deformation member 72, the deformation portions 71a and 72a. One of the deformation portions 71b and 72b contracts and the other expands. When an external force acts in a direction along a second direction orthogonal to the first direction (when acting in parallel with the connecting member 73), one of the deformed portion 73a and the deformed portion 73b contracts. And the other stretches. For this reason, the rotation suppressing member 70 does not hinder the swinging (tilting operation) of the support shaft 44.

  Further, when a force in the direction around the axis is applied to the support shaft 44, the deformed portions 71 a and 71 b of the deformable member 71, the deformed portions 72 a and 72 b of the deformable member 72, and the deformed portion 73 a of the connecting member 73. , 73b, an unreasonable force acts. Therefore, the reaction force at this time acts as a restraining force that prevents rotation. For this reason, the rotation suppressing member 70 can substantially prevent rotation of the support shaft 44 in the direction around the axis.

  As described above, by using the rotation suppressing member 70 as well, it is possible to allow the support shaft 44 to fall down and to suppress rotation in the direction around the axis.

  In the above embodiment, the return member is configured by the cross-shaped pressurizing spring 52 and the four wires 54 that can be easily bent and deformed. However, the present embodiment is not limited to this. Instead, the return member may be constituted by four coil springs stretched between the Z2 side surface of the upper yoke 42 and the fixing member 49.

  Further, even when the pressurizing spring 52 is used, the erection member does not necessarily need to be a wire 54 that can be easily bent and deformed, and is a stick-like member (also referred to as a bar) made of a rigid body. There may be. In this case, when the support shaft 44 swings, the one urging arm 52a of the pressurizing spring 52 is elastically deformed (pulled) in the pulling direction, and the other provided at the target position. The urging arm 52a is elastically deformed (compressed) in the direction in which it is pressed against the fixing member 49.

  Further, in the above embodiment, the moving side is shown as a so-called moving magnet type in which the movable side is configured by the magnetic field generating unit 41 having the permanent magnet M and the fixed side is formed by the coil unit 45, but the present invention is not limited to this. Absent. That is, a moving coil type in which a coil part is provided at a position on the movable part side where the magnetic field generation part 41 is provided and a magnetic field generation part is provided at a position on the fixed part side where the coil part 45 is provided. It may be.

  Moreover, although what was shown to the said embodiment demonstrated the case where an actuator was utilized for the galvanometer mirror which adjusts the angle of a mirror, this invention is not limited to a galvanometer mirror. For example, it can be used as an actuator for changing the direction of a small antenna.

An exploded perspective view showing an actuator of the present invention, Sectional view of the actuator, The perspective view which shows a magnetic field generation part from back, The coil part is shown, A is a top view of a coil part, B is sectional drawing in the BB line of A, Sectional view similar to FIG. 2 showing the operating state of the actuator, A plan view schematically showing the operation of the erection member when rotation around the support shaft occurs, A plan view and a side view of the rotation suppressing member in a state where the support shaft is in the neutral position, A plan view and a side view of the rotation suppressing member in a state after the support shaft has been swung; Schematic showing a state in which twist due to rotation has occurred in the connecting portion constituting the rotation suppressing member, The other embodiment of a rotation control member is shown, and a state in which a support axis is in a neutral position, The other embodiment of a rotation suppression member is shown, The state after a support shaft rock | fluctuates,

Explanation of symbols

10 Actuator 20 Mirror part (control target)
21 mirror 22 stage 23 base 40 magnetic drive unit 41 magnetic field generating unit 42 upper yoke 43 lower yoke 43a arm 43b through hole 44 support shaft 44a tip 45 coil unit 46 bobbin 49 fixing member 50 support mechanism unit 51 pivot ball bearing 51a small ball 51A Housing 52 Pressurizing Spring 52a Biasing Arm 54 Wire (Installation Member)
60 rotation suppression member 61 fixed ring 62 drive ring 63 restraint ring 65 first connection portion 66 second connection portion 70 rotation suppression members 71, 72 deformation members 71a, 71b, 72a, 72b deformation portions 73 connection members 73a, 73b deformation Part 73A Connecting ring g Gap C1, C2, C3, C4 Coil M Permanent magnet M1 Through hole

Claims (9)

A control object provided on the movable part side, a support shaft provided with the control object, a support mechanism provided on the fixed part side and swingably supported with respect to a predetermined reference axis; A driving mechanism that applies a driving force that swings the support shaft in a posture inclined from a neutral position that coincides with the reference axis, and a return member that applies a biasing force that returns the support shaft to the neutral position;
The actuator is characterized in that the support mechanism includes a plurality of small spheres arranged in a ring shape, and a tip of the support shaft is supported by the plurality of small spheres.   The return member is provided between the leaf spring provided on the fixed portion side, the leaf spring and the control target, and is pulled by the urging force of the leaf spring so that the support shaft is moved to the plurality of small balls. The actuator according to claim 1, comprising an erection member pressed against the actuator.   The actuator according to claim 2, wherein the erection member is a plurality of deformable wires or a plurality of sticks formed as a rigid body.   2. The actuator according to claim 1, wherein the return member is a plurality of coil springs that are stretched between the fixed portion and the control target and press tips of the support shaft against the plurality of small balls.   The actuator according to any one of claims 1 to 4, wherein the driving mechanism is driven by an electromagnetic force generated by a current flowing through a coil and a magnetic field of a permanent magnet.   The actuator according to any one of claims 1 to 5, wherein a rotation suppressing member is provided on the support shaft.   The rotation suppressing member includes a fixing ring provided on the outermost peripheral portion, a drive ring provided on the inner side thereof, a restraining ring provided on the innermost peripheral portion, and a first ring connecting the fixing ring and the driving ring. And a second connecting portion for connecting the drive ring and the restraining ring, the fixing ring is fixed to the fixing portion, and the support shaft is fixed to the center of the restraining ring. The actuator according to claim 6.   The first connecting part and the second connecting part are both formed of a pair of bellows, and a pair of bellows forming the first connecting part and a pair of bellows forming the second connecting part The actuators according to claim 7, which are provided at positions different from each other by 90 degrees.   The rotation suppressing member includes a pair of deformable members having deformable portions deformable in a first direction and a pair of deformable members that are deformable in a second direction orthogonal to the first direction. A connecting member to be connected and a connecting ring provided on the connecting member, both ends of the pair of deformable members are fixed to a fixed portion side, and the support shaft is fixed to the center of the connecting ring. 6. The actuator according to 6.

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