Rotary and reciprocating actuator

Abstract

To provide a rotary reciprocating drive actuator having high manufacturability, good assembly accuracy, and the ability to drive with high amplitude even if a movable object is a large mirror.SOLUTION: A rotary reciprocating drive actuator has: a shaft portion that supports a movable object; a movable body that has a movable magnet in which a first half and a second half of a ring shape that are fixed to the shaft portion on one side of the movable object in an axial direction, have a ring shape, and are divided by a magnetic pole switching portion that extends in a direction perpendicular to the axial direction, are magnetized to different poles; a fixed coil that is arranged on one side and rotates the movable object back and forth about the shaft portion by electromagnetic interaction with the movable magnet; and a base that supports the shaft portion via bearings on both sides of the movable object in the axial direction. The base is a U-shaped member formed with a pair of bearing arrangement surface portions, each of which has a bearing and is arranged on both sides opposite to each other and a joint surface portion that joins each of the pair of bearing arrangement surfaces. The joint surface portion is parallel to the shaft portion inserted into the bearings.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a rotary reciprocating drive actuator. [Background technology]

[0002] 2. Description of the Related Art Conventionally, as a rotary reciprocating actuator, a galvanometer motor is known which changes the reflection angle of a mirror that reflects laser light to irradiate a scanning target in a multifunction peripheral, a laser beam printer, or the like.

[0003] As a galvanometer motor, in addition to a type in which a coil is attached to a mirror to form a movable coil structure (called a "movable coil type"), various types such as the structure disclosed in Patent Document 1 are known.

[0004] Patent document 1 discloses a beam scanner in which four permanent magnets are provided on a rotating shaft to which a mirror is attached so as to be magnetized in the radial direction of the rotating shaft, and a core having magnetic poles around which a coil is wound is arranged on either side of the rotating shaft. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 4727509 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the movable coil type, the heat generated by the coil during operation may adversely affect the surface condition of the mirror, the state of attachment of the mirror to the rotation axis, or the shape of the mirror, including warping. In addition, in the movable coil type, it is difficult to increase the input current to the coil when considering the heat generated by the coil when current is applied, which is a problem that it is difficult to increase the size and amplitude of the mirror, which is the movable body. Furthermore, it is necessary to pull out the wiring to the coil to the fixed body side for the mirror, which is the movable body, which is a problem that assembly is difficult.

[0007] In addition, in Patent Document 1, the magnet is placed on the movable body side, which solves the problems with the movable coil type described above. However, in order to keep the magnet stationary in a neutral position relative to the core, in other words, to position the switching point of the magnet's magnetic poles in the center of the core, two magnets are required per core pole, for a total of four magnets.

[0008] This results in a problem that the amplitude of the movable body is smaller, i.e., the swing range is reduced, compared to when a similar scanner is constructed using, for example, a two-pole magnet. In addition, since at least four magnets are used, the number of parts is large, the configuration is complex, and assembly is difficult. In light of these circumstances, there has been a demand for rotary reciprocating actuators for use in scanners in recent years that are rigid, shock-resistant, and vibration-resistant, and that are easy to assemble and can achieve high amplitude, anticipating an increase in the size of the moving body, the mirror.

[0009] An object of the present invention is to provide a rotary reciprocating actuator that is easy to manufacture, has good assembly precision, and is capable of driving even a movable object, such as a large mirror, with high amplitude. [Means for solving the problem]

[0010] The rotary reciprocating actuator of the present invention comprises: a shaft portion that supports a movable object; and a shaft portion that is fixed to the shaft portion on one side of the movable object in the axial direction; Surrounding the shaft portion It has a ring shape, The ring shape classification The two A movable body having a movable magnet, the halves of which are magnetized to different poles; a fixed coil disposed on the one side and configured to rotate the movable body back and forth around the shaft portion by electromagnetic interaction with the movable magnet; The movable object is disposed inside the space between the pair of end surfaces, and the movable magnet and the fixed coil are disposed outside the space, and the shaft is supported parallel to the body surface via the bearings. Base and do . Effect of the Invention

[0011] According to the present invention, the manufacturability is high, the assembly precision is high, and even if the movable object is a large mirror, it can be driven with a high amplitude. [Brief description of the drawings]

[0012] [Figure 1] 1 is an external perspective view of a rotary reciprocating actuator according to a first embodiment of the present invention. [Diagram 2] 1 is an exploded perspective view of a rotary reciprocating actuator according to a first embodiment of the present invention. [Diagram 3] 1 is a plan view showing a configuration of a main part of a rotary reciprocating actuator according to a first embodiment of the present invention. [Figure 4] 1 is a vertical cross-sectional view showing a damping portion of a rotary reciprocating actuator according to a first embodiment of the present invention. [Diagram 5] 1 is an exploded perspective view showing a damping section of a rotary reciprocating actuator according to a first embodiment of the present invention. [Figure 6] FIG. 6A is a diagram showing a waveform in which ringing has been suppressed by the function of the attenuation section, and FIG. 6B is a diagram showing a waveform in which ringing is present. [Figure 7] 13A and 13B are diagrams illustrating modified examples of the attenuation portion. [Figure 8] 5A to 5C are diagrams illustrating the operation of the rotary reciprocating actuator by the magnetic circuit of the rotary reciprocating actuator according to the first embodiment of the present invention. [Figure 9] 5A to 5C are diagrams illustrating the operation of the rotary reciprocating actuator by the magnetic circuit of the rotary reciprocating actuator according to the first embodiment of the present invention. [Figure 10] FIG. 11 is an external perspective view of a rotary reciprocating actuator according to a second embodiment of the present invention. [Figure 11] FIG. 11 is an exploded perspective view of a rotary reciprocating actuator according to a second embodiment of the present invention. [Figure 12] FIG. 11 is an external perspective view of a rotary reciprocating actuator according to a third embodiment of the present invention. [Figure 13] FIG. 11 is a longitudinal sectional view showing a configuration of a main part of a rotary reciprocating actuator according to a third embodiment of the present invention. [Figure 14] FIG. 11 is an external perspective view of a rotary reciprocating actuator according to a fourth embodiment of the present invention. [Figure 15] 1 is a block diagram showing a configuration of a main part of a first example of a scanner system having a rotary reciprocating actuator; [Figure 16] FIG. 13 is a block diagram showing a configuration of a main part of a second example of a scanner system having a rotary reciprocating actuator. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0014] (Embodiment 1) Hereinafter, each part constituting the rotary reciprocating actuator 1 of this embodiment will be described based on the normal state in which the rotary reciprocating actuator 1 is not driven and is in a non-operating state. In addition, a Cartesian coordinate system (X, Y, Z) is used to explain the structure of the rotary reciprocating actuator 1 of this embodiment. The same Cartesian coordinate system (X, Y, Z) is used in the drawings described later. The axial direction includes the Z direction as well as the -Z direction.

[0015] FIG. 1 is an external perspective view of a rotary reciprocating drive actuator 1 according to embodiment 1 of the present invention, FIG. 2 is an exploded perspective view of the rotary reciprocating drive actuator 1 according to embodiment 1 of the present invention, and FIG. 3 is a plan view showing the main configuration of the rotary reciprocating drive actuator 1 according to embodiment 1 of the present invention.

[0016] The rotary reciprocating actuator 1 reciprocates and rotates the movable body 10 to which a movable object is connected around the shaft 13. The rotary reciprocating actuator 1 is, for example, provided with a mirror 16 as a movable object on the movable body 10, and is used as an optical scanner in LIDAR (Laser Imaging Detection and Ranging) or the like, which irradiates a scanning object with a laser beam or the like using the mirror 16 and acquires the reflected light to acquire information on the scanning object. The rotary reciprocating actuator 1 is applicable to scanning devices such as multifunction machines and laser beam printers. In particular, the rotary reciprocating actuator 1 can function favorably even in a situation where it is subjected to an external force, and is preferably applied to devices that may be subjected to impacts while traveling, such as a scanner device that can be mounted on a vehicle.

[0017] The rotary reciprocating drive actuator 1 has a movable body 10 having a movable magnet 30 and a shaft portion 13, and a fixed body 20 that rotatably supports the shaft portion 13 and has a coil 43 and a rotational angle position holding portion (hereinafter referred to as the "magnet position holding portion") 24 for the movable magnet 30.

[0018] In the rotary reciprocating actuator 1, the movable body 10 is held rotatably at the operation reference position in the normal state by the magnetic attraction force between the magnet position holder 24 and the movable magnet 30, that is, by a so-called magnetic spring. Here, in the normal state, the coil 43 is not energized. In this embodiment, the movable body 10 being at the operation reference position means that the movable magnet 30 is at a neutral position with respect to the magnetic poles 412a and 412b excited by the coil 43, and is at a position where the movable body 10 can rotate in both directions around the axis (forward and reverse rotations as viewed from the shaft portion 13 side). When the movable body 10 is at the operation reference position, a magnetic pole switching portion (also called a "magnetic pole switching portion") 34, which is a portion where the magnetic poles of the movable magnet 30 are switched, is located at a position facing the magnetic poles on the coil 43 side. The magnetic pole switching portion 34 is provided at two locations on the outer periphery of the movable magnet 30. The reference operating position is a position where the movable magnet 30 can rotate clockwise and counterclockwise with the same torque when it is driven to rotate and reciprocate around the shaft portion 13.

[0019] Through cooperation between the movable magnet 30 and the coil 43, the shaft portion 13 of the movable body 10 moves appropriately in one direction and the other direction around the axis from the operating reference position relative to the fixed body 20, and in this embodiment, is driven in a reciprocating rotational manner, that is, sways or vibrates.

[0020] [Movable body 10] Movable body 10 has shaft portion 13, movable magnet 30 fixed to shaft portion 13, and encoder disk 72 of rotation angle position detection portion 70 described later, and mirror 16 is fixed to shaft portion 13 via mirror holder 15. Mirror 16 reflects and emits incident laser light for scanning. Note that mirror 16 is attached to movable body 10 in this embodiment, and the mirror is used as a movable object to be capable of reciprocating rotational oscillation around shaft portion 13, but the movable object does not have to be mirror 16.

[0021] The shaft portion 13 is supported so as to be rotatable about its axis with respect to the fixed body 20. The shaft portion 13 may be supported in any manner as long as it is movably supported by the fixed body 20, and in this embodiment, the shaft portion 13 is supported via bearings 23a and 23b.

[0022] The shaft portion 13 is made of a durable metal (for example, SUS420J2) and is connected to a movable object. The movable object is a member that is to be driven to rotate in a reciprocating manner, and may be the movable body 10 itself.

[0023] The shaft portion 13 is supported by the fixed body 20 via bearings 23a and 23b at positions spaced apart in the axial direction. A mirror 16, which is a movable object, is fixed to a portion (here, the center portion) between the bearings 23a and 23b via a mirror holder 15. Furthermore, when attention is paid to the position of the bearing 23a, the bearing 23a is disposed on the shaft portion 13 between the movable magnet 30 and the mirror 16, which is a movable object.

[0024] The mirror 16 is attached so that the reflecting surface 16a is positioned in the tangential direction of the shaft portion 13, and the angle of the reflecting surface 16a can be freely changed by rotating the shaft portion 13.

[0025] The mirror 16 attached to the shaft portion 13 may be attached at a position (displaced position) closer to one of the two ends 13a, 13b over the entire length of the shaft portion 13. In that case, it is preferable that the mirror 16 is supported on the fixed body 20B via bearings 232, 234 (see the rotary reciprocating actuator 1B in Figures 12 and 13) on the other end 13b side of the shaft portion 13.

[0026] In this embodiment, shaft 13 is supported on base 22 via bearings 23a, 23b at both ends 13a, 13b so as to sandwich mirror 16. This makes mirror 16 more firmly held than if fixed by a cantilever, and is configured to have improved resistance to shock and vibration.

[0027] In addition, in this embodiment, a movable magnet 30 is fixed to one end 13a of the shaft portion 13, and a damper 60, which is an example of a damping portion and is attached to the fixed body 20, is connected to the other end 13b.

[0028] The movable magnet 30 has an even number of magnetic poles, alternately magnetized with S poles and N poles, on the outer periphery of the shaft portion 13 in a direction perpendicular to the direction of the rotation axis of the shaft portion 13. In this embodiment, the movable magnet 30 is magnetized with two poles, but may be magnetized with two or more poles depending on the amplitude during movement.

[0029] The movable magnet 30 has a ring shape. In the movable magnet 30, an even number of magnetic poles 31, 32 forming S poles and N poles are alternately magnetized on the outer periphery of the shaft portion 13. In this embodiment, the movable magnet 30 has an even number of magnetic poles 31, 32 each having a magnetized surface of different polarity facing in opposite directions across the shaft portion 13. In this embodiment, the magnetic poles 31, 32 have different polarities with a plane along the axial direction of the shaft portion 13 as a boundary. Moreover, these even-numbered magnetic poles 31 and 32 are configured by being magnetized at equal intervals on the outer periphery of the shaft portion 13 of the movable magnet 30 . In this manner, in the movable magnet 30, an even number of magnetic poles 31, 32 forming S poles and N poles are alternately arranged on the outer periphery of the shaft portion 13, and the magnetic poles 31, 32 are arranged at equal intervals.

[0030] 3, the movable magnet 30 has semicircular portions that form different magnetic poles 31 and 32 in plan view. In the movable magnet 30 of this embodiment, the arc-shaped curved surfaces of the semicircular portions are the magnetized surfaces of the different magnetic poles 31 and 32, and are configured to extend in the circumferential direction around the axis. In other words, the magnetized surfaces of the magnetic poles 31 and 32 are aligned in a direction perpendicular to the axial direction of the shaft portion 13, and are arranged so as to rotate and face the magnetic poles 412a and 412b of the first core 41a and the second core 41b, respectively. The number of magnetic poles of the movable magnet 30 is equal to the number of magnetic poles of the core.

[0031] The magnetic poles 31, 32 on the outer circumferential surface of the movable magnet 30 are switched at a magnetic pole switching portion 34 along the extending direction of the shaft portion 13.

[0032] The magnetic pole switching portions 34 of the magnetic poles 31, 32 of the movable magnet 30 are located at positions facing the center positions in the width direction of the magnetic poles 412a, 412b of the first core 41a and the second core 41b when no current is applied to the coil 43. The magnetic pole switching portions 34 are located at positions where the areas in the rotation direction are symmetrical to each of the magnetic poles 412a, 412b.

[0033] In the movable magnet 30, the magnetic poles 31, 32 and the magnetic pole switching portion 34 are movable in the circumferential direction around the axis as the shaft portion 13 rotates.

[0034] [Fixed body 20] The fixed body 20 supports the shaft portion 13 to movably support the movable body 10 . The fixed body 20 has a base 22 , bearings 23 a , 23 b , a magnet position holder 24 , a core fixing plate 27 , and a core unit 40 having a coil 43 .

[0035] The base 22 rotatably supports the shaft portion 13 of the movable body 10 in the rotary reciprocating actuator 1. In the present embodiment, the base 22 is shaped such that one side (here, one end on the -Y direction side) of one end surface portion 222 and the other end surface portion 224, which are spaced apart in the axial direction of the shaft portion 13, i.e., in the Z direction, and are arranged opposite to each other, is joined to both ends of a main body surface portion 226 extending in the axial direction. Specifically, the one end surface portion 222, the other end surface portion 224, and the main body surface portion 226 of the base 22 are each formed in a planar shape, and the one end surface portion 222 and the other end surface portion 224 are projected from both ends of the shaft portion 13 spaced apart in the axial direction so as to face each other on the main body surface portion 226. That is, the base 22 is formed in a substantially U-shape as a whole when viewed from the side.

[0036] One end surface portion 222 and the other end surface portion 224, which are spaced apart in the axial direction, have cutout holes 222a and 224a that face each other and penetrate in the axial direction (Z direction). The shaft portion 13 is inserted through the cutout holes 222a and 224a via bearings 23a and 23b, respectively.

[0037] The mirror 16 is rotatably disposed between the one end surface portion 222 and the other end surface portion 224 , and the mirror 16 is rotatable within the base 22 .

[0038] A core unit 40 is disposed on the outer surface (here, the left surface) of one end surface portion 222 of the base 22 on the axially outward side thereof so as to face the movable magnet 30 with an air gap G therebetween.

[0039] The core unit 40 is fixed to a core fixing plate 27, and the core fixing plate 27 is fixed to the left surface side of the one end surface portion 222 via a fastening material .

[0040] A rotation angle position detector 70 that detects the rotation angle of the shaft portion 13 is disposed on the other end surface portion 224 side. The rotation angle position detector 70 in this embodiment is a so-called optical encoder sensor, and has an encoder disk 72 attached to the shaft portion 13, as well as a sensor board 76 on which an optical sensor 74 that detects the rotation angle of the shaft portion 13 using the encoder disk 72 is mounted.

[0041] A sensor board 76 on which an optical sensor 74 is mounted is disposed on the other end surface 224. In this embodiment, the sensor board 76 is fixed to the other end surface 224 by a fastening material 28 such as a screw. The rotation angle position detection unit 70 detects the rotation angle of the shaft 13, i.e., the rotation angle of the mirror 16, by receiving light reflected from the encoder disk 72 with the optical sensor 74. As a result, the detection result can be used to control the swing range of the shaft 13 and mirror 16 when they are reciprocally rotated (swinged) by a control unit provided on the fixed body 20 side, for example.

[0042] The core unit 40 has a coil 43, and a core 41 including a first core 41a, a second core 41b, and a mounting core 41c around which the coil 43 is wound. In this embodiment, the magnet position holder 24 is provided on the mounting core 41c of the core unit 40.

[0043] Coil 43 excites the core when current is applied. In this embodiment, coil 43 is composed of coils 43a and 43b, each of which is wound around a bobbin 44. Bobbin 44 is inserted around core portion 411a of first core 41a and core portion 411b of second core 41b.

[0044] In this way, since coils 43a, 43b are arranged on both sides of the core positioned on either side of the movable magnet 30, the dimensions of coil 43 can be reduced and the magnetic force balance generated by coil 43 can be improved.

[0045] The first core 41a, the second core 41b and the mounting core 41c are each a laminated core, and are formed by laminating, for example, ferritic magnetic stainless steel plates.

[0046] The first core 41a and the second core 41b have an even number (here, two) of different magnetic poles 412a, 412b that are excited by energizing the coil 43. The number of magnetic poles of the core 41 is an even number, and may be two or more as long as it is the same as the number of magnetic poles 31, 32 of the movable magnet 30.

[0047] In this embodiment, the first core 41a and the second core 41b have core parts (411a, 411b) arranged in parallel in a direction perpendicular to the rotation axis direction so as to sandwich the movable magnet 30 in the direction perpendicular to the rotation axis direction. A bobbin 44 around which a coil 43 is wound is inserted on each of the core parts (411a, 411b). A mounting core 41c is mounted between one ends of the core parts (411a, 411b), and magnetic poles 412a, 412b are formed continuously to the other ends of the core parts (411a, 411b).

[0048] The two magnetic poles 412a and 412b are arranged to align in the rotation direction of the movable magnet 30.

[0049] In this embodiment, the two magnetic poles 412a, 412b are arranged facing each other across the movable magnet 30, with an air gap G between them, in a direction perpendicular to the axis of rotation of the movable magnet 30 from the outer periphery of the movable magnet 30 (corresponding to magnetic poles 31, 32).

[0050] The centers of the magnetic poles 412a, 412b in the length along the rotation direction of the movable magnet 30 (hereinafter referred to as the "center positions" of the magnetic poles 412a, 412b, respectively) face each other with the axis of the shaft portion interposed therebetween.

[0051] The magnetic pole switching portion 34 of the movable magnet 30 is disposed to face the center positions of the magnetic poles 412a, 412b. In this embodiment, the center positions of the magnetic poles 412a, 412b and the axis of the shaft portion 13 are disposed on the same straight line in a plan view.

[0052] In this embodiment, the magnetic poles 412a, 412b are formed in an arc shape corresponding to the outer circumferential surface of the movable magnet 30, and are arranged so as to surround the movable magnet 30 in the X direction.

[0053] The mounting core 41c, together with the first core 41a and the second core 41b, is disposed so as to surround the movable magnet 30 in a direction perpendicular to the rotation axis.

[0054] A magnet position holder 24, which is disposed opposite the movable magnet 30 with an air gap G therebetween, is attached to the mounting core 41c so as to protrude toward the movable magnet 30 side.

[0055] The magnet position holding unit 24 functions as a magnetic spring together with the moving magnet 30 due to the magnetic attraction force generated between it and the moving magnet 30, and holds the position of the rotating moving magnet 30 at an operating reference position (a predetermined rotation angle position).

[0056] The magnet position maintaining unit 24 is a magnet or a magnetic body. In this embodiment, the magnet position maintaining unit 24 is a magnet magnetized toward the moving magnet 30, and the magnetic attraction force between the magnet position maintaining unit 24 and the moving magnet 30 is increased compared to when the magnet position maintaining unit 24 is made of a magnetic body. In this embodiment, a magnet with the magnetization direction facing the moving magnet 30 is used.

[0057] The magnet position holder 24 is a magnet, and in this embodiment, the magnet position holder 24 positions the magnetic pole switching portion 34 of the moving magnet 30 at a position facing the magnetic poles 412a, 412b at the operation reference position. In this manner, the magnet position holder 24 and the moving magnet 30 attract each other, and the moving magnet 30 can be positioned at the operation reference position. As a result, the magnetic pole switching portion 34 of the moving magnet 30 faces the center positions of the magnetic poles 412a, 412b of the first core 41a and the second core 41b. As a result, the moving magnet 30 is stabilized at the operation reference position, and at that position, the coils 43 (43a, 43b) are energized to generate maximum torque and drive the movable body 10.

[0058] Furthermore, since the movable magnet 30 is magnetized with two poles, it is easy to achieve high amplitude in cooperation with the coil 43, and vibration performance can be improved.

[0059] The magnet position holder 24 has a facing surface that faces the outer circumferential surface of the movable magnet 30 with an air gap G therebetween. The facing surface is a curved surface that corresponds to the shape of the outer circumferential surface of the movable magnet 30. The magnet position retaining portion 24 is formed in a convex shape that protrudes from the mounting core 41c toward the movable magnet 30, and its tip surface serves as an opposing surface.

[0060] The magnet position holder 24 is, for example, a magnet whose opposing surface is magnetized to an N pole (see FIGS. 8 and 9).

[0061] The opposing surface which becomes the magnetic pole of the magnet position holding portion 24 is a portion along the rotational direction of the movable magnet 30, and faces the radially outside of the movable magnet 30, the portion between the portions of the outer peripheral surface of the movable magnet 30 where the magnetic poles 412a, 412b of the first core 41a and the second core 41b face each other.

[0062] When the magnet position holder 24 is made of a magnetic material, it may be formed integrally with the mounting core 41c, thereby making it possible to preferably realize the function of a magnetic spring with a small number of parts.

[0063] In the operating reference position, one of the magnetic poles of the movable magnet 30 faces the magnet position holder 24, and the magnetic pole switching portion 34 of the magnetic pole of the movable magnet 30 faces the center positions of the magnetic poles 412a, 412b of the first core 41a and the second core 41b.

[0064] In this embodiment, the core 41 excited by the coil 43 is composed of a first core 41a having a magnetic pole 412a, a second core 41b having a magnetic pole 412b, and a mounting core 41c mounted between the ends of the first core 41a and the second core 41b on the opposite side to the magnetic poles 412a and 412b. That is, the core 41 is composed of three divided bodies. Of these divided bodies, the mounting core 41c is provided with the magnet position holder 24. In this way, in the core 41, the core part on which the magnet position holder 24 is disposed is a separate body, so that the coil 43, the core 41, and the movable magnet 30 can be easily assembled to each other, and the ease of assembly can be improved, compared to the case where the magnet position holder 24 is integrally formed with the core including the part on which the coil 43 is wound.

[0065] FIG. 4 is a longitudinal cross-sectional view showing a damping portion of the rotary reciprocating drive actuator according to embodiment 1 of the present invention, and FIG. 5 is an exploded perspective view showing a damper of the rotary reciprocating drive actuator according to embodiment 1 of the present invention.

[0066] The damping section damps sharp resonance that occurs when movable body 10 is driven to rotate back and forth by energizing coil 43. In the present embodiment, damper 60 as the damping section is provided between shaft portion 13 and base 22, and damps resonance by applying a load to the rotation of shaft portion 13.

[0067] The attenuator 60 has, for example, a case 62 fixed to the base 22, a magnet 63, a rotor 64 arranged rotatably within the case 62 and fixed to the shaft portion 13, an upper cover portion 65, and a lower cover portion 66.

[0068] The case 62 is a cylindrical body, and a ring-shaped magnet 63 is attached along the circumferential direction to the inner peripheral surface of the case 62. A rotor 64 is disposed inside the magnet 63 with an air gap G2 therebetween.

[0069] The rotor 64 is a magnetic body having a disk portion 641, a recess 642 protruding from the center of the disk portion 641, and an outer cylinder portion 644 protruding from the outer edge side of the disk portion 641 and arranged concentrically on the outer periphery side of the recess 642. The other end 13b of the shaft portion 13 is inserted into and fixed in the recess 642 of the rotor 64. The outer cylinder portion 644 is arranged in the case 62 between the magnet 63 and the inner cylinder portion 652 of the upper cover portion 65 so as to be freely movable in the circumferential direction.

[0070] The lower surface side of the case 62 is closed by a lower cover portion 66, and the upper surface side of the case 62 is closed by a ring-shaped upper cover portion 65 so that the rotor 64 does not come off the case 62 and in a state where an open end of a recess 642 provided in the center of the rotor 64 is exposed. The damper 60 is fixed to the other end surface portion 224 by a flange on the upper surface side of the case 62 via a fastening material 29 such as a screw (see FIG. 2). In this embodiment, the case 62 is fixed to a boss portion (not shown) protruding to the outer surface side at the other end surface portion 224 via the fastening material 29, and the damper 60 is arranged so as to sandwich the rotation angle position detection unit 70 between the other end surface portion 224 and the damper 60.

[0071] Inside the case 62, a magnetic fluid R is filled between the magnet 63 and the rotor 64, and between the inner cylinder portion 652 of the upper cover portion 65 and the rotor 64.

[0072] When the movable body 10 rotates back and forth, the rotor 64 fixed to the other end 13b of the shaft 13 comes into contact with the magnetic fluid R in the case 62, and the damper 60 rotates back and forth while applying a load by the magnetic fluid R due to the magnetic attraction force of the magnet 63. This suppresses ringing shown in Fig. 6B, which occurs when the resonance is sharp when the movable body 10 moves, and realizes vibration that is easy to control by driving with a suitable waveform without ringing, that is, a so-called sawtooth wave, as shown in Fig. 6A. In addition, the damper 60 of this embodiment is configured such that the magnetic fluid R is interposed between the rotor 64 and the case 62 side, and the magnetic fluid R does not leak outside the damper 60 due to the magnet 63, thereby improving the reliability of the damper 60.

[0073] In the rotary reciprocating drive actuator 1 of this embodiment, the damper 60 as the damping section is a so-called rotary damper in which a magnetic fluid R is interposed between the rotor 64 and the case 62 on the fixed body side, but a fluid that damps the rotational force of the rotor 64 relative to the case 62 may be used instead of the magnetic fluid R. In other words, the damper 60 may be configured in any way as long as it damps the rotation of the rotor 64 connected to the movable body 10 and damps sharp resonance that occurs when the movable body 10 is driven to rotate reciprocally.

[0074] For example, in the configuration of the attenuator 60, the magnet 63 may be removed, the sealing between the case 62, the upper cover 65 and the lower cover 66 may be improved by sealing or the like, and oil may be used instead of the magnetic fluid R.

[0075] According to this configuration, the attenuator 60 does not require the magnet 63, making it possible to reduce the size of the attenuator itself and to improve ease of assembly.

[0076] Moreover, the damping portion may be the magnetic fluid itself, and may be disposed in the air gap G between the moving magnet 30 and the magnetic poles 412a, 412b, or in the air gap G between the moving magnet 30 and the magnet position holder 24. With this configuration, it is not necessary to use a rotary damper such as the damper 60 of the present embodiment as a separate component. Moreover, by applying the magnetic fluid to the portions sandwiching the air gap G between the moving magnet 30 and the magnetic poles 412a, 412b, or to the portions sandwiching the air gap G between the moving magnet 30 and the magnet position holder 24, the magnetic fluid can be easily disposed between these air gaps G, and the damping function for damping resonance can be realized at low cost and in a small space.

[0077] 7, an electric filter 78 such as a low-pass filter, a band-elimination filter, or a notch filter may be provided as an attenuation section between a power supply section (drive signal supply section 77) that supplies a drive signal to the rotary reciprocating drive actuator 1 and the rotary reciprocating drive actuator 1 to remove frequency components that cause ringing. Note that the electric filter 78 is mounted on a drive board (not shown) that drives the coil 43, and the drive board is provided on the fixed body 20.

[0078] By providing electrical filter 78 to attenuate resonance, ringing can be suitably suppressed without being affected by temperature or individual differences in components, as compared to a mechanical attenuation structure.

[0079] [Magnetic circuit configuration of rotary reciprocating actuator 1] Figures 8 and 9 are diagrams showing the operation of the rotary reciprocating drive actuator by the magnetic circuit of the rotary reciprocating drive actuator according to embodiment 1 of the present invention, and Figure 9 shows the operation of the rotary reciprocating drive actuator when the direction of current flow to the coil in Figure 8 is reversed.

[0080] In the rotary reciprocating drive actuator 1, when no current is applied to the coil 43, the movable magnet 30 is positioned at the operating reference position (a predetermined rotation angle position) by the magnetic attraction force between the magnet position holder 24 and the movable magnet 30, i.e., the magnetic spring.

[0081] In the normal state, i.e., in the operating reference position, one of the magnetic poles 31, 32 of the movable magnet 30 is attracted to the magnet position holder 24, and the magnetic pole switching portion 34 is positioned opposite the center positions of the magnetic poles 412a, 412b of the first core 41a and the second core 41b.

[0082] As shown in FIG. 8, for example, in a configuration in which the facing surface of the magnet position holder 24 facing the moving magnet 30 is magnetized to an N pole, a magnetic spring torque (indicated by arrow FM in FIG. 8) is generated which rotates the moving magnet 30 so as to attract the magnetic pole 32 of the moving magnet 30 which is magnetized to an S pole.

[0083] In this manner, in the rotary reciprocating actuator 1 of the present embodiment, in a normal state, that is, when the movable magnet 30 is located at the operation reference position, the magnetic pole switching portion 34 of the movable magnet 30 (specifically, both ends of the linear magnetic pole switching portion 34) is disposed at a position facing the magnetic poles 412a, 412b of the first core 41a and the second core 41b. As a result, when the coil 43 is energized, the movable body 10 can be driven in a desired rotational direction by excitation of the coil 43 according to the energization direction of the coil 43, and the torque for rotationally driving the movable body 10 can be maximized.

[0084] The coil 43 (43a, 43b) is wound so that when current is applied to the coil 43, it excites the first core 41a and the second core 41b, causing the magnetic poles 412a, 412b of the first core 41a and the second core 41b to have opposite polarities. In this embodiment, when current is applied to coil 43 (43a, 43b) in the direction shown in FIG. 8, coil 43 (43a, 43b) excites first core 41a and second core 41b, so that magnetic pole 412a is magnetized as a north pole and magnetic pole 412b is magnetized as a south pole.

[0085] In detail, the energized coils 43a and 43b magnetize the cores (411a and 411b) around which they are wound. In the first core 41a, for example, a magnetic flux is generated that is emitted from the magnetic pole 412a, which is an N pole, to the movable magnet 30, flows through the movable magnet 30, the magnet rotation position holder 24, and the mounting core 41c in this order, and enters the core 411a.

[0086] In the second core 41b, a magnetic flux is formed which is emitted from the core portion 411b to the mounting core 41c side, flows through the mounting core 41c, the magnet rotation position holder 24, and the movable magnet 30 in this order, and is incident on the magnetic pole 412b.

[0087] As a result, the magnetic pole 412a magnetized to the N pole attracts the S pole of the movable magnet 30, and the magnetic pole 412b magnetized to the S pole attracts the N pole of the movable magnet 30, and a torque in the F direction about the axis of the shaft portion 13 is generated in the movable magnet 30, causing it to rotate in the F direction. Accordingly, the shaft portion 13 also rotates, and the mirror 16 fixed to the shaft portion 13 also rotates.

[0088] Furthermore, when the current flow direction of the coil 43 is switched to the opposite direction, the magnetic poles 412a, 412b in the first core 41a and the second core 41b excited by the coil 43 are magnetized with magnetic poles different from those in the previous current flow direction to the coil 43. Specifically, when current is applied in a direction different from the current flow direction shown in Fig. 8 (see Fig. 9), the magnetic pole 412a is magnetized as an S pole and the magnetic pole 412b is magnetized as an N pole, and the flow of magnetic flux is also reversed. When the current flow direction is switched, a magnetic spring torque FM is generated by the magnetic attraction force between the magnet rotation position holder 24 and the movable magnet 30, i.e., the magnetic spring, and the movable magnet 30 moves to the operation reference position.

[0089] 9, magnetic pole 412a magnetized to an S pole attracts the N pole of movable magnet 30, and magnetic pole 412b magnetized to an N pole attracts the S pole of movable magnet 30, causing torque to be generated in movable magnet 30 in a direction opposite to the F direction around the axis of shaft 13, causing movable magnet 30 to rotate in a direction opposite to the F direction (-F direction). Accordingly, shaft 13 also rotates in the opposite direction (-F direction), and mirror 16 fixed to shaft 13 also rotates in a direction opposite to the previous moving direction (-F direction). By repeating this, mirror 16 is driven to rotate back and forth.

[0090] In this way, the rotary reciprocating actuator 1 is driven by an AC wave input to the coil 43 from a power supply unit (for example, a power supply unit having the same function as the drive signal supply unit 77 in FIG. 7). That is, the current direction of the coil 43 is switched periodically, and a thrust in the F direction due to a torque in the F direction about the axis and a thrust due to a torque in the opposite direction to the F direction (-F direction) are alternately applied to the movable body 10. As a result, the movable body 10 is driven to rotate in a reciprocating manner around the axis 13, that is, it vibrates. Note that, at the time of switching when the thrust due to the torque in the F direction and the torque in the -F direction are alternately applied to the movable body 10, the magnetic spring torques FM and -FM act on the movable body 10 to move it to the operation reference position.

[0091] The following is a brief explanation of the driving principle of the rotary reciprocating drive actuator 1. In the rotary reciprocating drive actuator 1 of this embodiment, the moment of inertia of the movable body 10 is J [kg m 2 ], the spring constant in the torsional direction of the magnetic spring (magnetic poles 412a, 412b, magnet position holder 24, and movable magnet 30) is K sp In this case, the movable body 10 has a resonance frequency F with respect to the fixed body 20, which is calculated by the following formula (1): r Vibrates at [Hz].

[0092]

number

[0093] Since the movable body 10 constitutes a mass portion in a vibration model of a spring-mass system, the coil 43 is applied with the resonance frequency F r When an AC wave having a frequency equal to the resonant frequency F of the movable body 10 is input to the coil 43 from the power supply unit, the movable body 10 enters a resonant state. r By inputting an AC wave having a frequency substantially equal to that of the movable body 10, the movable body 10 can be vibrated efficiently.

[0094] Below are equations of motion and circuit equations showing the driving principle of the rotary reciprocating actuator 1. The rotary reciprocating actuator 1 is driven based on the equation of motion shown in the following equation (2) and the circuit equation shown in the following equation (3).

[0095]

number

[0096]

number

[0097] That is, the moment of inertia J [kg m 2 ], rotation angle θ(t) [rad], torque constant K t [N·m / A], current i(t) [A], spring constant K sp [N m / rad], damping coefficient D [N m / (rad / s)], load torque T Loss [N m], etc. can be changed as appropriate within the range that satisfies formula (2). In addition, the voltage e(t) [V], resistance R [Ω], inductance L [H], and back electromotive force constant K e [V / (rad / s)] can be changed as appropriate within the range that satisfies formula (3).

[0098] In this way, in the rotary reciprocating actuator 1, the moment of inertia J of the movable body 10 and the spring constant K of the magnetic spring are sp The resonant frequency F is determined by rWhen the coil 43 is energized with an AC wave corresponding to the above, a large vibration output can be efficiently obtained.

[0099] The rotary reciprocating actuator of this embodiment has high torque generation efficiency, is less likely to transfer heat to the mirror, which is the movable object, and ensures precision in the flatness of the reflecting surface 16a of the mirror 16. In addition, it is easy to manufacture, has good assembly precision, and can drive even a large mirror, which is the movable object, with high amplitude.

[0100] The rotary reciprocating actuator 1 of the first embodiment and rotary reciprocating actuators 1A, 1B, and 1C described below are capable of resonant driving, but are also capable of non-resonant driving. In addition, ringing can be suppressed by increasing the damping coefficient using a damping section.

[0101] (Embodiment 2) FIG. 10 is an external perspective view of a rotary reciprocating drive actuator 1A according to the second embodiment of the present invention, and FIG. 11 is an exploded perspective view of the rotary reciprocating drive actuator 1A according to the second embodiment of the present invention.

[0102] 10 and 11 is configured such that a magnetic sensor is used instead of the optical sensor that constitutes the rotation angle position detection unit 70 in the configuration of the rotary reciprocating drive actuator 1, and the other configuration is the same as that of the rotary reciprocating drive actuator 1. Therefore, in the explanation of the rotary reciprocating drive actuator 1A, components that are the same as those in the rotary reciprocating drive actuator 1 are given the same names and reference numerals, and explanations thereof will be omitted.

[0103] The rotary reciprocating actuator 1A includes a movable body 10A having a movable magnet 30A and a shaft portion 13A, and a fixed body 20A that rotatably supports the shaft portion 13A and has a coil 43 and a magnet position holder 24. In the rotary reciprocating actuator 1A, the movable magnet 30A in the movable body 10A is ring-shaped and is configured by magnetizing an even number of magnetic poles, S poles and N poles, alternately on the outer periphery of the shaft portion 13A. The two even magnetic poles 412a, 412b of the core 41 in the fixed body 20A are arranged opposite the movable magnet 30A on the outer periphery side of the shaft portion 13A with an air gap G therebetween. The number of magnetic poles of the core 41 is equal to the number of magnetic poles of the movable magnet 30A.

[0104] In the rotary reciprocating actuator 1A, the movable body 10A is rotatably held by the fixed body 20A so as to be located at the operation reference position in the normal state by the magnetic attraction force between the magnet position holding portion 24 and the movable magnet 30A, that is, by a so-called magnetic spring. Here, the normal state is a state in which no current is passed through the coil 43. The state in which the movable body 10A is located at the operation reference position is a state in which the movable magnet 30A is located at a neutral position with respect to the magnetic pole excited by the coil 43, and the magnetic pole switching portion 34 of the movable magnet 30A is located at a position facing the magnetic pole on the coil 43 side.

[0105] Movable body 10A has shaft portion 13A, movable magnet 30A fixed to shaft portion 13A, and magnetic sensor magnet 72A sensed by magnetic sensor 74A of rotation angle position detection portion 70A.

[0106] A mirror 16 is fixed to the shaft portion 13A via a mirror holder 15A.

[0107] The fixed body 20A has a base 22A, bearings 23a and 23b, a magnet position holder 24, a core fixing plate 27A, and a core unit 40 having a coil 43.

[0108] The base 22A has a shape in which one end surface portion 222A and the other end surface portion 224A, which are arranged opposite to each other and spaced apart in the axial direction (Z direction), are joined by a main body surface portion 226A extending in the axial direction. Note that a core fixing plate 27A to which the core unit 40 is fixed is fixed to the one end surface portion 222A of the base 22A via a fastening material 28A such as a screw.

[0109] In the base 22A, bearings 23a, 23b are fitted into the notches in the one end surface portion 222A and the other end surface portion 224A. The shaft portion 13A is inserted into the bearings 23a, 23b, and the shaft portion 13A is rotatably supported by the base 22A via the bearings 23a, 23b.

[0110] The other end surface portion 224A rotatably supports the shaft portion 13A on the outer side in the axial direction. A rotational angle position detection unit 70A is disposed on the axially outer side of the other end surface portion 224A.

[0111] The rotation angle position detection unit 70A has a magnetic sensor magnet 72A, a magnetic sensor 74A, and a sensor board 76A on which the magnetic sensor 74A is mounted.

[0112] The magnetic sensor magnet 72A is fixed integrally via a holder 73A to the end surface of the other end 13b of the shaft portion 13A, which protrudes axially outward from the other end surface portion 224A.

[0113] The magnetic sensor 74A senses the magnetic sensor magnet 72A that rotates together with the shaft 13A by being driven, and detects the rotation angle of the shaft 13A and, in turn, the mirror 16. The sensor board 76A is fixed to the fixing member 75A via a fastening material 28A such as a screw. The fixing member 75A is fixed to the other end surface 224A via a fastening material 29A such as a screw. As a result, the magnetic sensor 74A is disposed at a position facing the magnetic sensor magnet 72A in the axial direction on the other end surface 224A. The sensor board 76A drives the magnetic sensor 74A, and enables the rotation angle of the shaft 13A acquired by the magnetic sensor 74A, that is, the position corresponding to the rotation angle, to be fed back to a power supply unit (for example, a power supply unit having a function similar to that of the drive signal supply unit 77 in FIG. 7).

[0114] In this embodiment, it is possible to achieve the same basic effects as the rotary reciprocating drive actuator 1, and it is possible to simplify the structure and reduce the production costs compared to the case where an optical sensor is used.

[0115] (Embodiment 3) FIG. 12 is an external perspective view of a rotary reciprocating drive actuator 1B according to embodiment 3 of the present invention, and FIG. 13 is a vertical cross-sectional view showing the configuration of a main portion of the rotary reciprocating drive actuator 1B according to embodiment 3 of the present invention.

[0116] 12 and 13 has a magnetic circuit configuration similar to that of the rotary reciprocating actuator 1, and a mirror 16B is fixed to one end of a shaft portion 13B, and is supported by a base 22B at the other end 13b of the shaft portion 13B. Note that, in the rotary reciprocating actuator 1B as well, a ring-shaped movable magnet 30 in the movable body 10B is configured by alternately magnetizing an even number of magnetic poles forming S poles and N poles on the outer periphery of the shaft portion 13B, and two even magnetic poles 412a, 412b in the fixed body 20B are equal in number to the magnetic poles of the movable magnet 30, and are disposed opposite the movable magnet 30 with an air gap G interposed therebetween on the outer periphery side of the shaft portion 13B.

[0117] The rotary reciprocating actuator 1B is configured to be able to reciprocally rotate a mirror 16B by using a so-called pivot structure.

[0118] Specifically, in a movable body 10B having a shaft portion 13B and a movable magnet 30 fixed to the shaft portion 13B, an encoder disk 72 and a scanning mirror 16B are fixed to the shaft portion 13B. The scanning mirror 16B is fixed to the shaft portion 13B via a mirror holder 15B. In the fixed body 20B having the core unit 40, the bearings 232, 234 are fitted adjacent to each other in a through-hole formed in the base 22B, and the bearings 232, 234 are inserted through the base 22B.

[0119] The base 22B is a plate-shaped base disposed on the XY plane, and a core unit 40 is fixed via a core fixing plate 27 to one end surface side (left surface side) of the base 22B.

[0120] A rotation angle position detection unit 70 is disposed on the other end face (right side face) of the base 22B, that is, on the face opposite to the face on which the core unit 40 is disposed in the base portion 22B. An encoder disk 72 attached to the shaft portion 13B and a sensor board 76 are disposed on the other end face (right side face) side of the base 22B, and an optical sensor 74 facing the encoder disk 72 can detect the rotation angle of the shaft portion 13B. In addition, an attenuator 60 is provided on the right side face side of the base 22B, located to the right of the rotation angle position detection unit 70.

[0121] The other end 13b of the shaft portion 13B, which is inserted through the base 22B via bearings 232, 234, is joined to a rotor 64 (see FIGS. 6 and 7) of the damper 60 similar to that of the first embodiment.

[0122] Thus, in the rotary reciprocating actuator 1B, the shaft 13B has one end to which the mirror 16B is fixed, and the other end is supported by the base 22B so as to be capable of reciprocating rotation. On the base 22B side, the movable magnet 30 is fixed to one end surface of the base 22B in the shaft 13B, and the encoder disk 72 of the rotation angle position detector 70 and the rotor of the attenuator 60 are fixed to the other end surface of the base 22B via bearings 234 and 232.

[0123] The encoder disk 72 is positioned adjacent to the bearing 234, and the rotary reciprocating drive actuator 1B has a shaft portion 13B fixed to the mirror 16B whose length is shorter than that of the shaft portion 13 of the rotary reciprocating drive actuator 1 of embodiment 1, thereby enabling the mirror 16B to be rotated in a reciprocating manner.

[0124] In the rotary reciprocating actuator 1B, the mirror 16B is fixed to one end 13a of the shaft 13B, and is supported by two bearings 232, 234 at the other end 13b of the shaft 13B. This allows the mirror 16B, the movable magnet 30, and the bearings 232, 234 to be arranged adjacent to each other along the shaft 13B, and the rotary reciprocating actuator 1B itself can be made smaller than a configuration in which the bearings 232, 234 are arranged at a distance. The rotary reciprocating actuator 1B, like the rotary reciprocating actuator 1, has high torque generation efficiency, is less likely to transfer heat to the mirror, which is the movable object, and can ensure the accuracy of the flatness of the reflecting surface of the mirror 16B. In addition, it is easy to manufacture, has good assembly accuracy, and can drive the mirror 16B with high amplitude.

[0125] (Embodiment 4) FIG. 14 is an external perspective view of a rotary reciprocating actuator according to a fourth embodiment of the present invention.

[0126] 14 has the same magnetic circuit configuration as the rotary reciprocating actuator 1, and in the same configuration as the rotary reciprocating actuator 1, a mirror 16C that drives in two axial directions is used instead of the mirror 16 that drives in one axial direction. Therefore, in the rotary reciprocating actuator 1C, the same components as those in the rotary reciprocating actuator 1 are given the same reference numerals and names, and descriptions thereof will be omitted.

[0127] In the rotary reciprocating drive actuator 1C, a mirror 16C having a reflective mirror portion 162 that is driven to rotate reciprocally on two axes by a driving source including a core unit 40 and a movable magnet 30 that utilizes electromagnetic interaction is provided so that it can be driven to rotate reciprocally in a direction perpendicular to the axial direction of the shaft portion 13.

[0128] The mirror 16C includes a separate drive unit that drives the reflecting mirror portion 162 of the mirror 16C relative to the shaft portion 13 in a direction perpendicular to the rotation direction of the shaft portion 13. Mirror 16C having a separate drive unit is, for example, a MEMS (Micro Electro Mechanical System) mirror, and is configured to be able to rotate reflective mirror portion 162 of mirror 16C at high speed around one axis perpendicular to shaft portion 13 based on a drive signal supplied by, for example, vertical drive signal supply unit 207 (see FIG. 16). As a result, reflective mirror portion 162 of mirror 16C is driven to reciprocate and rotate around shaft portion 13 by driving core unit 40 and movable magnet 30, and is also driven to reciprocate and rotate in a direction perpendicular to the axial direction by the separate drive unit. The rotary reciprocating actuator 1C has high torque generation efficiency, is less likely to transfer heat to the mirror 16C which is the movable object, and can ensure the precision of the flatness of the reflecting mirror portion 162 which is the reflecting surface. In addition, it is easy to manufacture, has good assembly precision, and can drive the mirror 16C with high amplitude even if it is a large mirror.

[0129] [Outline of scanner system configuration] FIG. 15 is a block diagram showing the configuration of the main parts of a first example of a scanner system 200A having a rotary reciprocating actuator, and FIG. 16 is a block diagram showing the configuration of the main parts of a second example of a scanner system 200B having a rotary reciprocating actuator.

[0130] A scanner system 200A shown in FIG. 15 includes a laser emission unit 201, a laser control unit 202, an actuator 203, a drive signal supply unit 204, and a position control signal calculation unit 205.

[0131] In scanner system 200A, an object is scanned using a rotary reciprocating actuator 203 capable of driving a mirror to rotate reciprocally on one axis. As rotary reciprocating actuator 203, for example, rotary reciprocating actuators 1 to 1B of the present embodiment can be used.

[0132] The laser control unit 202 drives the laser emission unit 201 to control the emitted laser. The laser emission unit 201 is, for example, an LD (laser diode) serving as a light source and a lens for converging the output laser. The laser light from the light source is emitted to the mirror 16 of the actuator 203 via a lens system.

[0133] The position control signal calculation unit 205 generates and outputs a drive signal for controlling the shaft unit 13 (mirror 16) to be at the target angular position, with reference to the actual angular position of the shaft unit 13 (mirror 16) acquired by the rotation angle position detection unit 70 and the target angular position. For example, the position control signal calculation unit 205 generates a position control signal based on the actual angular position of the shaft unit 13 (mirror 16) acquired and a signal indicating the target angular position converted using sawtooth waveform (see FIG. 6A) data stored in a waveform memory (not shown), and outputs the signal to the drive signal supply unit 204.

[0134] The drive signal supplying unit 204 supplies a desired drive signal to the coil 43 of the actuator 203 to rotate and reciprocate the actuator 203 and scan the object.

[0135] Scanner system 200B shown in FIG. 16 includes laser emission unit 201 and laser control unit 202 similar to those of scanner system 200A, as well as actuator 203A, horizontal scanning angle position detection unit 702 provided in actuator 203A, horizontal drive signal supply unit 204A, position control signal calculation unit 205, vertical scanning angle position detection unit 206, vertical drive signal supply unit 207, and position control signal calculation unit 208.

[0136] In scanner system 200B, an object is scanned using actuator 203A capable of driving a mirror (specifically, reflective mirror portion 162) to rotate back and forth on two axes, and the rotary reciprocating drive actuator 1C of this embodiment can be used as actuator 203A.

[0137] The rotary reciprocating actuator 1C as the actuator 203A is driven to rotate back and forth about the shaft portion 13, thereby horizontally emitting laser light reflected by the reflective mirror portion 162 of the mirror 16C. Also, in the rotary reciprocating actuator 1C, the reflective mirror portion 162 is driven to rotate back and forth about an axis extending in a direction perpendicular to the shaft portion 13.

[0138] The horizontal scanning angle position detector 702 has the same function as the rotation angle position detector 70 , and detects the rotation angle position of the shaft portion 13 , and therefore the reflection mirror portion 162 around the shaft portion 13 , and outputs it to the position control signal calculator 205 .

[0139] The position control signal calculation unit 205 generates a position control signal for controlling the target angular position using the actual angular position of the shaft unit 13 (angle position in horizontal scanning of the mirror 16) acquired by the horizontal scanning angle position detection unit 702 and sawtooth waveform (see FIG. 6A) data stored in a waveform memory (not shown), and outputs the signal to the horizontal drive signal supply unit 204A. The horizontal drive signal supply unit 204A has the same function as the drive signal supply unit 204, and outputs a drive signal to the coil 43 of the actuator 203A to rotate and reciprocate the reflection mirror unit 162 of the actuator 203 in the horizontal scanning direction, thereby horizontally scanning the target object.

[0140] Vertical scanning angular position detection unit 206 detects the rotational angular position of reflection mirror unit 162 as it rotates about an axis (here, the X-axis) perpendicular to shaft unit 13 , and outputs the detection result to position control signal calculation unit 208 .

[0141] Based on the actual axis portion 13 acquired by vertical scanning angle position detection portion 206, i.e., the actual angular position in vertical scanning of mirror 16, and information indicating a target angular position converted using sawtooth waveform data for vertical scanning stored in a waveform memory (not shown), position control signal calculation portion 208 generates a position control signal for controlling to reach the target angular position, and outputs it to vertical drive signal supply portion 207. Vertical drive signal supply portion 207 outputs a drive signal to actuator 203A to rotate and reciprocate reflective mirror portion 162 of actuator 203A in the vertical scanning direction, thereby vertically scanning the object.

[0142] The configuration functioning as the damping section in this embodiment may be modified as appropriate and applied to the rotary reciprocating actuators 1, 1A, 1B, and 1C of the embodiment, and may also be combined as appropriate. For example, a damper 60 that is a rotary damper using magnetic fluid R, a rotary damper using oil instead of magnetic fluid in the damper 60, and an electric filter 78 such as a low-pass filter, a band-elimination filter, or a notch filter may be combined. This allows for even greater damping of resonance, suppresses ringing, and provides the rotary reciprocating actuators 1, 1A, 1B, and 1C with high controllability. This improves the reliability of the rotary reciprocating actuators 1, 1A, 1B, and 1C.

[0143] In the present embodiment, the coil 43 on the fixed body 20, 20B side is provided in the core unit 40, but the present embodiment may be configured without a core. For example, the vibration actuator 1 may be configured as a rotary reciprocating actuator having a movable body having a shaft portion 13 and a movable magnet 30 fixed to the shaft portion 13, and a fixed body having a coil 43 and supporting the shaft portion 13 rotatably, without a core 41, and the movable body 10 may be reciprocally rotated around the shaft portion 13 relative to the fixed body by electromagnetic interaction between the coil 43 and the movable magnet 30. In this case, the movable magnet has a ring shape similar to the movable magnet 30, and is formed by alternately magnetizing even numbers of magnetic poles 31, 32 forming S poles and N poles on the outer periphery of the shaft portion 13. Similarly to the coil 43, the coil is arranged in the fixed body at a position where a torque is generated to rotate the movable magnet by electromagnetic interaction with the movable magnet. For example, the coils are arranged in positions such that, due to electromagnetic interaction between the coils and the moving magnet, a torque is generated between the coils and each of the even magnetic poles, causing the moving magnet to rotate back and forth.

[0144] Therefore, in a vibration actuator that does not have a core 41 and is otherwise configured in the same manner as the vibration actuator 1, the moving magnet can obtain the same action and effect as the moving magnet 30. Moreover, in this vibration actuator, the number of magnetic poles magnetized by the coil 43 is equal to the number of magnetic poles of the moving magnet. Moreover, the even-numbered magnetic poles magnetized by the coil are arranged to face the moving magnet 30 with an air gap G sandwiched between them in the radial direction of the shaft. In addition, the fixed body has a rotation angle position holder 24 that is arranged to face the moving magnet 30 with the air gap G sandwiched between them and holds the rotation angle position of the moving magnet 30 by the magnetic attraction force generated between the moving magnets 30. This configuration provides high manufacturability, good assembly accuracy, and the movable object can be driven with high amplitude.

[0145] The above describes the embodiment of the present invention. Note that the above description is an example of a preferred embodiment of the present invention, and the scope of the present invention is not limited thereto. In other words, the description of the configuration of the above device and the shape of each part are examples, and it is clear that various modifications and additions to these examples are possible within the scope of the present invention.

[0146] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2018-121167, filed on June 26, 2018, are incorporated herein by reference in their entirety. [Industrial Applicability]

[0147] INDUSTRIAL APPLICABILITY The rotary reciprocating drive actuator according to the present invention has the advantages of being highly manufacturable, having good assembly precision, and being able to drive even a large mirror as a movable object with high amplitude, and is particularly useful for use in scanners that rotate mirrors and require durability. [Explanation of symbols]

[0148] 1, 1A, 1B, 1C Rotary and reciprocating actuator 10, 10A, 10B Movable body 13, 13A, 13B shaft part 13a One end 13b Other end 15, 15A, 15B Mirror Holder 16, 16B, 16C Mirror 162 Reflecting mirror part 16a Reflective surface 20, 20B fixed body 22, 22A, 22B Base 222, 222A One end surface 222a, 224a Notched holes 224, 224A Other end surface 226, 226A Main body surface part 23a, 23b, 232, 234 Bearings 24 Magnet position holder 27, 27A Core fixing plate 28, 28A, 29, 29A Fastening material 30 Moving Magnet 31, 32 magnetic pole 34 Magnetic pole changeover section 40 Core Unit 41 cores 41a 1st Core 41b 2nd Core 41c Installation core 411a, 411b core 412a, 412b magnetic pole 43, 43a, 43b Coil 44 Bobbin 60 Attenuator 62 cases 63 Magnet 64 Rotating Body 641 Disc Club 642 Recess 644 Outer cylinder 65 Top cover 652 Inner cylinder 66 Lower lid part 70, 70A Rotation angle position detector 702 Horizontal scanning angle position detector 72 Encoder disk 72A Magnetic Sensor Magnet 73A Holder 74 Optical Sensor 74A Magnetic Sensor 75A Fixing material 76, 76A Sensor board 77 Drive signal supply unit 78 Electrical Filters 200A, 200B Scanner System 201 Laser emission unit 202 Laser control unit 203, 203A Actuator 204 Drive signal supply unit 204A Horizontal drive signal supply unit 205, 208 Position control signal calculation unit 206 Vertical scanning angle position detector 207 Vertical drive signal supply unit

Claims

1. a movable body including a shaft portion supporting a movable object, and a movable magnet fixed to the shaft portion on one side of the movable object in the axial direction, having a ring shape surrounding the shaft portion, the ring shape being divided into two C-shaped halves magnetized to different poles; a fixed coil disposed on the one side and configured to rotate the movable body back and forth around the shaft portion by electromagnetic interaction with the movable magnet; a base having a flat main body surface portion, and a pair of end surface portions each provided with a bearing, the end surface portions being protruded from both ends of the main body surface portion in opposition to each other so as to form a U-shaped member together with the main body surface portion, the base disposing the movable object inside a space between the pair of end surface portions, the movable magnet and the fixed coil being disposed outside the space, and supporting the shaft portion in parallel with the main body surface portion via the bearing; Rotary reciprocating drive actuator.

2. A hole in which the bearing is disposed is formed in each of the pair of end surface portions.

2. The rotary reciprocating drive actuator of claim 1.

3. The holes are cut-out holes formed by cutting the pair of end surface portions from their respective ends to their respective central portions where the bearings are positioned.

3. The rotary reciprocating drive actuator of claim 2.

4. The two C-shaped halves are separated by a magnetic pole switching portion extending in a direction perpendicular to the axial direction.

2. The rotary reciprocating drive actuator of claim 1.

5. A unit including the fixed coil is fixed, and further includes a plate fixed to one of the pair of end surface portions.

2. The rotary reciprocating drive actuator of claim 1.

6. The movable object includes a mirror.

2. The rotary reciprocating drive actuator of claim 1.

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