Rotary reciprocating drive actuator

Abstract

To easily assemble while securing rigidness of a core, to suppress manufacturing cost, and to drive a movable object with high amplitude.SOLUTION: A rotation reciprocation drive actuator has a movable body having a shaft part to which a movable object is connected and a magnet fixed to the shaft part, a fixed body having a core assembly including a core body having a plurality of magnetic poles and a plurality of coils, and arranging the core assembly by making the plurality of magnetic poles face a circumference of the magnet, and a pair of shaft support bodies sandwiching the core assembly in an extension direction of the shaft part and rotatably supporting respective shaft parts on both sides of the core assembly. By energization to the plurality of coils, magnetic flux passing through the core body is generated, and the movable body is reciprocated and rotated around a shaft of the shaft part by electromagnetic interaction between the magnetic flux and the magnet.SELECTED DRAWING: Figure 4

Description

Technical Field

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

Background Art

[0002] Conventionally, a rotary drive actuator has been used as an actuator for scanners such as multifunction devices and laser beam printers. Specifically, the rotary reciprocating drive actuator realizes optical scanning of an object by changing the reflection angle of laser light by reciprocally rotating the mirror of the scanner.

[0003] As this type of rotary reciprocating drive actuator, one using a galvanometer motor is disclosed in Patent Document 1. As the galvanometer motor, various types are known, such as those of the type having the structure disclosed in Patent Document 1 and the coil movable type in which a coil is attached to a mirror.

[0004] Patent Document 1 discloses a beam scanner in which four permanent magnets are provided so as to be magnetized in the radial direction of the rotation axis to which the mirror is attached, and a core having magnetic poles around which a coil is wound is arranged so as to sandwich the rotation axis.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] By the way, in a coil movable type rotary reciprocating drive actuator, heat generated by the coil during driving may have an adverse effect on the surface state of the mirror, the joining state of the mirror to the rotating shaft, the shape of the mirror including warpage, etc. Further, in a coil movable type rotary reciprocating drive actuator, considering the heat generation of the coil during energization, it is difficult to increase the input current to the coil, and there is a problem that it is difficult to increase the size or amplitude of the mirror which is a movable body. Furthermore, there is a problem that wiring to the coil needs to be drawn out to the fixed body side with respect to the mirror which is a movable body, and the assemblability is poor.

[0007] Further, in the device of Patent Document 1, a rotating shaft is installed between a pair of bearing walls that are spaced apart from each other and opposed to each other, and a mirror that is a movable object, a coil and a magnet that rotate and reciprocate the mirror are disposed.

[0008] In recent years, rotary reciprocating drive actuators used in scanners are desired to be miniaturized and space-saving in accordance with the size of miniaturized scanner products. Therefore,

[0009] The present invention has been made in consideration of the above points, and provides a rotary reciprocating drive actuator that can be made smaller and more space-saving, has impact resistance and vibration resistance characteristics, and can drive a movable object through a shaft portion in a more stable state and with a high amplitude.

Means for Solving the Problems

[0010] One aspect of the rotary reciprocating drive actuator of the present invention is a movable body having a shaft portion to which a movable object is connected and a magnet fixed to the shaft portion, a core assembly including a core body having a plurality of magnetic poles and a plurality of coils, and a fixed body in which the core assembly is disposed with the plurality of magnetic poles opposed to the outer periphery of the magnet, a pair of shaft supports that sandwich the core assembly in the extending direction of the shaft portion and rotatably support the shaft portion on both sides of the core assembly, and has By energizing the plurality of coils, a magnetic flux passing through the core body is generated, and the movable body is reciprocally rotated around the axis of the shaft portion by the electromagnetic interaction between the magnetic flux and the magnet. se The core body includes a magnetic pole core having an integrated structure including the plurality of magnetic poles, a magnetic path core that forms a magnetic path of the magnetic flux together with the magnetic pole core, and the magnetic pole core and the magnetic path core are assembled to each other by being sandwiched between the shaft supports in a state of facing each other and being in surface contact with each other in the extending direction of the shaft portion. Adopt a configuration. One aspect of the rotary reciprocating drive actuator of the present invention is a movable body having a shaft portion to which a movable object is connected and a magnet fixed to the shaft portion, a pair of parallel rod-shaped bodies each having a plurality of magnetic poles disposed at their respective tip portions facing the outer periphery of the magnet, and a plurality of coils are respectively disposed thereon, and a rectangular frame-shaped body surrounding the pair of rod-shaped bodies, wherein a base end portion of the pair of rod-shaped bodies is connected to form a surrounding portion that constitutes a magnetic path connecting between the plurality of magnetic poles, and a core assembly including the surrounding portion, a pair of shaft supports that sandwich the core assembly in the extending direction of the shaft portion and rotatably support the shaft portion on both sides of the core assembly, and has a configuration in which, by energizing the plurality of coils, a magnetic flux passing through the pair of rod-shaped bodies and the surrounding portion is generated, and the movable body is reciprocally rotated about the axis of the shaft portion by an electromagnetic interaction between the magnetic flux and the magnet.

Advantages of the Invention

[0011] According to the present invention, it is possible to achieve more miniaturization and a smaller space, has impact resistance and vibration resistance characteristics, and can drive a movable object through a shaft portion in a more stable state with a high amplitude.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Embodiments for Carrying Out the Invention

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

[0014] FIG. 1 is an external perspective view of the rotary reciprocating drive actuator of the embodiment, FIG. 2 is a perspective view of the drive unit of the rotary reciprocating drive actuator, and FIG. 3 is a longitudinal sectional view of the drive unit. Further, FIG. 4 is a front side exploded perspective view of the rotary reciprocating drive actuator. Further, FIG. 5 is a rear side exploded perspective view of the rotary reciprocating drive actuator.

[0015] The rotary reciprocating drive actuator 1 is used, for example, in a LiDAR (Laser Imaging Detection and Ranging) device. Note that the rotary reciprocating drive actuator 1 is also applicable to optical scanning devices such as multifunction printers and laser beam printers.

[0016] As shown in FIG. 1, the rotary reciprocating drive actuator 1 mainly includes a mirror unit 22, a drive unit 10 that rotatably supports and drives the mirror unit 22 in a reciprocating rotation manner, and an angle sensor unit 70 that detects the rotational angle position of the mirror unit 22.

[0017] <Mirror unit 22> The mirror unit 22 is a movable object in the rotary reciprocating drive actuator 1 and is connected to the rotary shaft 24. The mirror unit 22 is formed, for example, by attaching a mirror 221 to one surface of a mirror holder 222. One end of the rotary shaft 24 is inserted into and fixed in the insertion hole 223 of the mirror holder 222. In the rotary shaft 24, a movable magnet (hereinafter simply referred to as "magnet") 26 is fixed at a portion disposed within the unit fixing portion 30 of the drive unit 10. The magnet 26 is driven in a reciprocating rotation manner by the magnetic flux generated by the unit fixing portion 30 described later.

[0018] <Drive unit 10> As shown in FIGS. 1 to 5, the drive unit 10 includes a unit movable portion 20 having a rotary shaft 24 and a magnet 26, and a unit fixing portion 30 that drives the unit movable portion 20 in a reciprocating rotation manner.

[0019] The drive unit 10 supports the mirror unit 22 with the rotary shaft 24 protruding from the cube-shaped unit fixing portion 30, and drives the mirror unit 22 in a reciprocating rotation manner via the rotary shaft 24. The unit fixing portion 30 may have any shape such as a columnar shape or a rectangular parallelepiped shape. In the present embodiment, since the unit fixing portion 30 is cube-shaped, the arrangement space can be reduced, and it can be arranged in a space-saving manner such as a corresponding cubic gap. In the drive unit 10, the rotary shaft 24 is supported so as to be reciprocally rotatable in a state where it passes through the unit fixing portion 30 and both ends protrude from the unit fixing portion 30. The unit movable portion 20, together with the mirror unit 22, constitutes the movable body of the rotary reciprocating drive actuator 1.

[0020] <Unit fixing portion 30> As shown in FIGS. 2 to 3, the unit fixing portion 30 is composed of each portion of the drive unit 10 except for the rotating shaft 24 and the magnet 26.

[0021] The unit fixing portion 30 constitutes a fixing body of the rotary reciprocating drive actuator 1. The unit fixing portion 30 has a core assembly 40 that houses the magnet 26 of the unit movable portion 20 inside and from which the rotating shaft 24 of the unit movable portion 20 protrudes, a first shaft support 50, and a second shaft support 60.

[0022] The unit fixing portion 30 sandwiches the core assembly 40 between the first shaft support 50 and the second shaft support 60 from both sides in the extending direction of the rotating shaft 24, and is configured by fixing the first shaft support 50 and the second shaft support 60 to the core assembly 40.

[0023] In the unit fixing portion 30, the first shaft support 50, the core assembly 40, and the second shaft support 60 are integrally fixed by an adhesive 32. In the unit fixing portion 30, both end faces of the rectangular core assembly 40 on both sides in the extending direction of the rotating shaft 24 are entirely covered by the first shaft support 50 and the second shaft support 60, respectively.

[0024] <Core assembly 40> FIG. 6 is a diagram for explaining the core assembly of the rotary reciprocating drive actuator, and is a perspective view seen from the second shaft support side by cutting the unit fixing portion 30 at the axial center. FIG. 6 is a cross-sectional view showing the main part configuration of the core assembly of the rotary reciprocating drive actuator, and is a cross-sectional view taken along line A-A in FIG. 3.

[0025] The core assembly 40 has coils 44 and 45, a core body K around which the coils 44 and 45 are wound, and a rotational angle position holding portion 48.

[0026] In the present embodiment, the core assembly 40 is formed in a rectangular shape with magnetic poles 411a and 412a disposed inside.

[0027] <Core body K> FIG. 7 is an exploded view of the core body. In this embodiment, the core body K is configured by axially combining two divided bodies. The core body K includes a pole core 41 having an integral structure including a plurality of magnetic poles 411a and 412a, and a magnetic path core 42 that is magnetically coupled and integrated with the pole core 41 and forms a magnetic path together with the pole core 41.

[0028] In this embodiment, the core body K includes rod-shaped bodies 411 and 412 having a plurality of magnetic poles 411a and 412a, and an enclosure portion 420 that is disposed so as to surround the four sides of the rod-shaped bodies 411 and 412 and forms a magnetic path connecting between the magnetic poles 411a and 412a. In this embodiment, the core body K is formed by combining the pole core 41 and the magnetic path core 42, and has a length in the axial direction longer than the width of the magnetic path. The core body K is composed of rectangular parallelepiped rod-shaped bodies 411 and 412 and an enclosure portion 420 formed in a rectangular frame shape at the rectangular side portions.

[0029] The pole core 41 and the magnetic path core 42 allow the magnetic flux generated when the coils 44 and 45 are energized to pass through the plurality of magnetic poles 411a and 412a. The pole core 41 and the magnetic path core 42 are, for example, laminated cores formed by laminating electromagnetic steel sheets (laminated members) such as silicon steel sheets. By forming the pole core 41 and the magnetic path core 42 in a laminated structure, they can be formed at low cost and in a complex shape.

[0030] <Pole core 41> The pole core 41 has an integral structure including a plurality of rod-shaped bodies 411 and 412 each having a plurality of magnetic poles 411a and 412a at their tip portions, and a connecting frame-shaped body 413 connecting the plurality of magnetic poles 411a and 412a.

[0031] The rod-shaped bodies 411 and 412 extend parallel to each other from the base end portions 411b and 412b to the tip portions (including the magnetic poles 411a and 412a), and a plurality of coils 44 and 45 are respectively externally mounted at the intermediate portions.

[0032] When excited by energizing the coils 44 and 45, the magnetic poles 411a and 412a at the tip portions of the rod-shaped bodies 411 and 412 generate polarities corresponding to the energization directions.

[0033] The rod-shaped bodies 411 and 412 have the same thickness as the thickness of the core body K (the length in the extending direction of the rotation axis 24). The rod-shaped bodies 411 and 412 are flush with each other in terms of the surfaces on one side (the lower side in FIG. 1) with respect to the connecting frame-shaped body 413, but on the other side (the upper side in FIG. 1), the rod-shaped bodies 411 and 412 are arranged at positions protruding more than the connecting frame-shaped body 413.

[0034] Thus, on the other side surface, a stepped portion is provided by the rod-shaped bodies 411 and 412 and the connecting frame-shaped body 413, and this stepped portion engages with the stepped portion on the magnetic path core 42 side. As a result, the rod-shaped bodies 411 and 412 and the surrounding portion are substantially flush with each other on the surfaces on both axial sides.

[0035] The portions of the magnetic poles 411a and 412a facing the magnet 26 have a shape that curves along the outer peripheral surface of the magnet 26. These curved shapes are arranged, for example, to face each other in a direction orthogonal to the extending direction of the rod-shaped bodies 411 and 412.

[0036] The magnetic poles 411a and 412a have, for example, outer dimensions that allow the bobbins 46 and 47 around which the coils 44 and 45 are wound to be inserted from the tip side. As a result, from the tip side in the extending direction of the rod-shaped bodies 411 and 412, that is, from the tips of the magnetic poles 411a and 412a, the bobbins 46 and 47 can be inserted and positioned up to a position surrounding the rod-shaped bodies 411 and 412.

[0037] The connecting frame-shaped body 413 is U-shaped and connects the rod-shaped bodies 411 and 412 to integrally join a plurality of magnetic poles 411a and 412a. Note that when the magnetic pole core 41 is assembled to the magnetic path core 42, the connecting frame-shaped body 413 abuts against the surrounding portion 420 of the magnetic path core 42 to surround and form a magnetic path. The connecting frame-shaped body 413 has a straight connecting side portion 413a and protruding side portions 413b and 413c that extend in a direction orthogonal to the connecting side portion 413a from both end portions of the connecting side portion 413a.

[0038] The connecting side portion 413a extends and is arranged in a direction orthogonal to the parallel direction of the rod-shaped bodies 411 and 412, and each of the both end portions is provided integrally with the base end portions 411b and 412b of the rod-shaped bodies 411 and 412. In the connecting side portion 413a, the rod-shaped bodies 411 and 412 are joined in parallel with the protruding side portions 413b and 413c between the protruding side portions 413b and 413c.

[0039] The connecting side portion 413a mainly connects the base end portions 411b and 412b of the rod-shaped bodies 411 and 412 and the base end portions 421b and 422b of the side portions 421 and 422 of the magnetic path core 42, and forms a magnetic path arranged so as to surround the coils 44 and 45. Mounting holes 40a are provided at the corners where the connecting side portion 413a and the protruding side portion 413b, and the connecting side portion 413a and the protruding side portion 413c are joined respectively. These corners are also the corners among the four corners in a plan view of the core body K. A fixing material 32 is inserted into the mounting holes 40a to fix the first shaft support 50, the magnetic path core 42, and the second shaft support 60.

[0040] The protruding side portions 413b and 413c have planar magnetic pole side contact surfaces 4130 that are in surface contact with the connecting side portion 413a and the magnetic path side contact surface 420a of the magnetic path core 42 respectively.

[0041] The magnetic pole side contact surface 4130 is provided entirely at a portion of the U-shaped connecting frame-like body 413 that faces the magnetic path core 42. The connecting frame-like body 413 is joined by bringing the magnetic pole side contact surface 4130 into surface contact with the magnetic path side contact surface 420a of the magnetic path core 42, and is joined in a state of being entirely laminated on the magnetic path side connecting side portion 424 of the magnetic path core 42.

[0042] In addition, positioning holes 40c for positioning each part are provided in the connecting side portion 413a when the magnetic path core 42, the first shaft support 50, and the second shaft support 60 are integrally joined.

[0043] Note that in the magnetic pole core 41, since the rod-shaped bodies 411 and 412 and the connecting frame-shaped body 413 have an integral structure, when assembling the rotary reciprocating drive actuator 1, the positional relationship of the plurality of magnetic poles 411a and 412a does not change. That is, when arranging the magnetic poles 411a and 412a at positions facing the magnet 26 and arranging the unit fixing portion 30 as the core body of the core assembly 40 together with the magnetic path core 42, the magnetic poles 411a and 412a can be positioned at accurate facing positions without shifting relative to each other.

[0044] <Magnetic path core 42> The magnetic path core 42 is connected to the magnetic pole core 41 and forms a magnetic path through which magnetic flux passes through the magnetic poles 411a and 412a when the coils 44 and 45 are energized.

[0045] The magnetic path core 42 faces the connecting frame-shaped body 413 of the magnetic pole core 41 in the extending direction of the rotary shaft 24 and is in surface contact with each other, and is assembled with the magnetic pole core 41 in a state where a plurality of magnetic poles 411a and 412a are positioned around the rotary shaft 24.

[0046] The magnetic path core 42 has, in addition to the surrounding portion 420, a magnetic path side contact surface 420a, a notch portion 420b, an engagement recess 40b, and a positioning hole 40d.

[0047] The magnetic path core 42 has a surrounding portion 420 that surrounds the coils 44 and 45, and a connecting frame-shaped body 413 of the magnetic pole core 41 engages and connects at a notch portion 420b of a part of the surrounding portion 420. The surrounding portion 420 is arranged around the rotary shaft 24 so as to surround not only the coils 44 and 45 but also the magnetic poles 411a and 412a.

[0048] The surrounding portion 420 is formed in a rectangular frame shape, for example, and has high strength. When the connecting frame-shaped body 413 engages with the surrounding portion 420 of the magnetic path core 42, the magnetic path side contact surface 420a and the magnetic pole side contact surface 4130 are in surface contact and adhere to each other, and it becomes an integrated rectangular frame-shaped body with the same thickness (axial length) on all four sides.

[0049] The surrounding portion 420 can stably position the magnetic poles 411a and 412a of the magnetic pole core 41. Further, since the surrounding portion 420 of the magnetic path core 42 surrounds the coils 44 and 45 from all sides, contact from the outside to the coils 44 and 45 can be prevented.

[0050] Specifically, the surrounding portion 420 has a magnetic path side connection side portion 424 joined in a frame shape, both side portions 421, 421, and a bridging portion 423. In the surrounding portion 420, the notch portion 420b is formed by notching a part of each of the magnetic path side connection side portion 424 and both side portions 421, 422 on the opposing surface side with respect to the magnetic pole core 41.

[0051] The magnetic path side contact surface 420a is U-shaped corresponding to the connection frame body 413, and is provided on the bottom surface portion of the notch portion 420b, that is, a part of the surfaces on the magnetic pole 41 side of the magnetic path side connection side portion 424 and both side portions 421, 422. By contacting so that the magnetic path side contact surface 420a overlaps the entire magnetic pole side contact surface 4130 of the connection frame body 413, the magnetic resistance at the joint portion between the surrounding portion 420 and the connection frame body 413 can be reduced.

[0052] The side portions 421, 422 are arranged to extend along the parallel direction of the pair of rod-shaped bodies 411, 412 so as to sandwich the pair of rod-shaped bodies 411, 412. The side portions 421, 422 are joined to both end portions of the magnetic path side connection side portion 424 at the base end portions 421b, 422b, and a bridging portion 423 parallel to the magnetic path side connection side portion 424 is installed between the tip end portions.

[0053] In a state where the magnetic path side connection side portion 424 is laminated so as to abut and overlap the connection frame body 413, the base end surfaces of the plurality of rod-shaped bodies 411, 412 abut on the surface on the magnet 26 side of the magnetic path side connection side portion 424, and magnetic flux can easily pass through.

[0054] The engaging recess 40b is provided at each of the four corners of the surrounding portion 420, that is, at the bent portions of the corners of the magnetic path, so as to extend in the axial direction. The mounting leg portion 56 of the first shaft support 50 is fitted into the engaging recess 40b.

[0055] The positioning holes 40d and 40e are holes used for positioning the axially stacked parts that make up the unit fixing part 30. The positioning hole 40d has the same axis and diameter as each of the positioning hole 40c of the magnetic pole core 41, the positioning hole 501 of the first shaft support 50, and the positioning hole 60a of the second shaft support 60, and forms a continuous positioning through-hole in the axial direction.

[0056] The positioning hole 40e has the same axis and diameter as each of the positioning hole 502 of the first shaft support 50 and the positioning hole 60b of the second shaft support 60, and forms a continuous positioning through-hole in the axial direction. The positioning hole 40e of the magnetic path core 42, the positioning hole 502 of the first shaft support 50, and the positioning hole 60b of the second shaft support 60 are elongated holes in this embodiment.

[0057] FIG. 8 is an exploded perspective view of the drive unit for explaining the assembly of the drive unit. In this configuration, when joining the core assembly 40, the first shaft support 50, and the second shaft support 60, as shown in FIG. 8, the positioning holes 40c, 40d, 501, and 60a are arranged so as to be continuous in the axial direction, and a positioning rod is inserted therethrough. In addition, by arranging the positioning holes 40e, 502, and 60b so as to be continuous in the axial direction and inserting a positioning rod therethrough, positioning can be performed when joining the core assembly 40, the first shaft support 50, and the second shaft support 60.

[0058] In this way, the core assembly 40 is sandwiched in a state where it is positioned by the first shaft support 50 and the second shaft support 60 respectively. Next, the fastening material 32 is inserted from the side of the second shaft support 60 in the order of the fastening hole 60c of the second shaft support 60, the mounting hole 40a of the core assembly 40, and the fastening hole 503 of the first shaft support 50 and tightened. Thereby, the first shaft support 50 and the second shaft support 60 are fixed to the core assembly 40 in a state of sandwiching the core assembly 40.

[0059] In this way, the positioning holes 40c, 40d, 501, 60a and the positioning holes 40e, 502, 60b each function as a common positioning hole. By inserting a rod into these common positioning through-holes and positioning each part based on this, and then assembling the reciprocating rotary drive actuator 1, the assembly accuracy can be improved, the reduction of the reciprocating rotation performance can be suppressed, and the occurrence of variations in the reciprocating rotation output can be suppressed.

[0060] In the state where the reciprocating rotary drive actuator 1 is assembled, the rotary shaft 24 is inserted into the space surrounded by the magnetic poles 411a, 412a. Further, in this space, a magnet 26 attached to the rotary shaft 24 is located, and the magnetic poles 411a, 412a face the magnet 26 at an accurate position via the air gap G.

[0061] The coils 44, 45 are wound around cylindrical bobbins 46, 47. The coil bodies composed of the coils 44, 45 and the bobbins 46, 47 are externally inserted onto the rod-shaped bodies 411, 412 of the magnetic pole core 41, so that the coils 44, 45 are arranged to wind around the rod-shaped bodies 411, 412. Thus, the coils 44, 45 are arranged adjacent to the magnetic poles 411a, 412a at the tip portions of the rod-shaped bodies 411, 412.

[0062] The winding directions of the coils 44, 45 are set so that when energized, magnetic flux is preferably generated from one of the magnetic poles 411a, 412a of the magnetic pole core 41 to the other.

[0063] <Rotational Angle Position Holding Portion (Magnet Position Holding Portion) 48> The rotational angle position holding portion 48 is incorporated into the core assembly 40 so as to face the magnet 26 via the air gap G in the state where the reciprocating rotary drive actuator 1 is assembled. The rotational angle position holding portion 48 may be fixed to the unit fixing portion 30, for example, the core assembly 40. The rotational angle position holding portion 48 is attached, for example, to the bridging portion 423 of the magnetic path core 42 (the portion above the rod-shaped bodies 411, 412 of the magnetic pole core 41) in a posture where the magnetic pole faces the magnet 26.

[0064] The rotation angle position holding part 48 is constituted by, for example, a magnet different from the magnet 26, generates a magnetic attractive force with the magnet 26, and attracts the magnet 26. That is, the rotation angle position holding part 48 forms a magnetic spring with the magnet 26 together with the rod-shaped bodies 411 and 412. Due to this magnetic spring, when the coils 44 and 45 are not energized (non-energized state), the rotation angle position of the magnet 26, that is, the rotation angle position of the rotary shaft 24 is held at the neutral position.

[0065] The neutral position is the rotation center position of the reciprocating rotation operation of the magnet 26 and is the reference position that is the center position of the swing of the magnet 26. When the magnet 26 is held at the neutral position by the magnetic attractive force with the rotation angle holding part 48, the boundary portions 26c and 26d of the magnet 26 face the magnetic poles 411a and 412a of the rod-shaped bodies 411 and 412. Also, based on the state where the magnet 26 is at the neutral position, the mounting posture of the mirror part 22 is adjusted. Note that the rotation angle position holding part 48 does not have to be a magnet and may be constituted by a magnetic body that generates a magnetic attractive force with the magnet 26.

[0066] <The first shaft support 50 and the second shaft support 60> The first shaft support 50 and the second shaft support 60 shown in FIGS. 2 to 6 and FIG. 8 function as electromagnetic shields, rotatably support the rotary shaft 24, sandwich the core assembly 40, and are fixed to the core assembly 40.

[0067] The first shaft support 50 and the second shaft support 60 are respectively arranged on both axial sides of the core body K of the core assembly 40. The first shaft support 50 and the second shaft support 60 can suppress the incidence of noise from the outside to the core body K and the emission of noise from the core body K to the outside. Note that the first shaft support 50 and the second shaft support 60 are each provided with a positioning recess 15 on the side surface, which functions as a positioning when mounting the rotary reciprocating drive actuator 1 itself on the product. Thereby, for example, the positioning of the rotary reciprocating drive actuator 1 can be performed by engaging the positioning recess 15 with an engaging portion provided at the mounting location of the product.

[0068] The first shaft support 50 and the second shaft support 60 each have a support main body portion 52, 62 provided with through holes 521, 62a, and bearings 54, 64 fitted into the through holes 521, 62a.

[0069] The support main body portions 52, 62 are each made of an electrically conductive material and cover the respective end faces of the core assembly 40, specifically, the core body K, which are spaced apart in the axial direction. The support main body portions 52, 62 of the first shaft support 50 and the second shaft support 60 are preferably formed of, for example, an aluminum alloy. The aluminum alloy has a high degree of design freedom and can easily impart a desired rigidity. Therefore, it is suitable when the first shaft support 50 and the second shaft support 60 function as bearing supports for receiving and supporting the rotating shaft 24.

[0070] FIG. 9 is a rear - side perspective view of the first shaft support 50. As shown in FIGS. 2 to 6, FIG. 8, and FIG. 9, the first shaft support 50 is attached to the core assembly 40 so as to cover the core assembly 40 from one - end side of the rotating shaft 24.

[0071] The first shaft support 50 has a first bearing 54 fitted into a through hole 521 of a support main body 52. A rotary shaft 24 is rotatably inserted into the first bearing 54. The first support 50 supports the rotary shaft 24 in a reciprocatingly rotatable manner via the first bearing 54 provided in the support main body 52 with one end portion thereof protruding. Note that a bearing mounting portion is formed on the back surface side (core assembly 40 side) in the through hole 521.

[0072] The first bearing 54 is attached into the through hole 521 in a state where the flange portion of the first bearing 54 is engaged with the opening edge portion of the through hole 521 to restrict movement in the fitting direction by penetrating from the core assembly 40 side (back surface side) into the bearing mounting portion on the back surface in the support main body 52. The bearing mounting portion is formed, for example, in a concave shape continuous with the through hole 51a on the back surface of the first shaft support 50, and the first bearing 54 is fitted into this concave shape. Note that the first bearing 54 is constituted by, for example, a rolling bearing or a sliding bearing.

[0073] FIG. 10 is a diagram for explaining a core holding portion in the core assembly 40, and shows a state in which the core assembly 40 is cut in a direction orthogonal to the axial direction at the tip portion of the core holding portion 58. In the present embodiment, the first shaft support 50 has a core holding portion 58 that protrudes from the support main body 52 to the inside of the core assembly 40.

[0074] The core holding portion 58 is disposed and interposed between magnetic paths of the core body K of the core assembly 40 to suppress movement of the magnetic paths. The core holding portion 58 is interposed between the magnetic poles 411a, 412a and the side portions 421, 422, protruding side portions 413b, 413c that constitute the magnetic paths. Thereby, in the core assembly 40, the magnetic poles 411a, 412a can be prevented from moving with respect to the side portions 421, 422, protruding side portions 413b, 413c that constitute the magnetic paths with the magnetic poles 411a, 412a and can be held in that position.

[0075] Therefore, deformation and the like of the core body K in the core assembly 40 against impact and vibration can be suppressed. The core holding portion 58 may be interposed between each of the magnetic poles 411a and 412a and both side portions of the large surrounding portion formed by the integrated side portions 421 and 422 and the protruding side portions 413b and 413c. As shown in FIG. 10, the core holding portion 58 protrudes from the back surface of the support main body portion 52 of the first shaft support body 50 and is arranged to protrude to a height up to the central portion of the magnetic poles 411a and 412a.

[0076] In addition, positioning holes 501 and 502 and mounting leg portions 56 are provided on the support main body portion 52 of the first shaft support body 50.

[0077] The positioning holes 501 and 502 are formed to penetrate axially through the central portions of the opposing side portions of the support main body portion 52, respectively.

[0078] The mounting leg portions 56 are provided to protrude from the four corners on the back surface side of the support main body portion 52. The mounting leg portions 56 are used to integrally join the first shaft support body 50, the second shaft support body 60, and the core assembly 40.

[0079] The shape of the mounting leg portions 56 corresponds to, for example, the shape of the engaging concave portion 40b of the core body K. Fixing holes 503 penetrating axially are formed in the mounting leg portions 56, respectively. A fixing material 32 for fixing the first shaft support body 50 to the second shaft support body 60 is inserted into the fixing holes 503. The first shaft support body 50 and the second shaft support body 60 are fixed to the core assembly 40 via the fixing material 32 inserted into the fixing holes 503.

[0080] The mounting leg portions 56 are arranged on the four corner side portions extending along the axial direction of the rotation shaft 24 in a rectangular columnar shape including a cube shape, a rectangular parallelepiped shape, etc., for example, in the unit fixing portion 30 having a cube shape, and engage with the engaging concave portion 40b of the core assembly 40. In this engaged state, the fixing material 32 is inserted into the fixing holes 503 in the mounting leg portions 56, passes through the mounting holes 40a at the four corners of the corresponding core assembly 40, and is fixed to the second shaft support body 60.

[0081] As a result, the first shaft support 50 restricts the core body K, and thus the core assembly 40, from moving only in the axial direction away from the first shaft support 50, and also restricts the movement in the axial direction by the fixing material 32 and is fixed. That is, the first shaft support 50 and the core assembly 40 are restricted from moving in a direction intersecting the axial direction of the rotation shaft 24 with respect to each other, and are reliably attached integrally.

[0082] The second shaft support 60 is attached to the core assembly 40 so as to cover the core assembly 40 from the other end side of the rotation shaft 24.

[0083] The second shaft support 60 has a second bearing 64 fitted into the through hole 62a of the support main body portion 62. The rotation shaft 24 is rotatably inserted through the second bearing 64. The second shaft support 60 supports the rotation shaft 24 in a reciprocally rotatable manner via the second bearing 64 provided in the support main body portion 62 with the other end portion side protruding. Note that a bearing mounting portion is formed on the back surface side (core assembly 40 side) of the through hole 62a.

[0084] The second bearing 64 is attached in a state where the flange portion is engaged with the opening edge portion of the through hole 62a by penetrating from the core assembly 40 side into the bearing mounting portion, and the movement in the fitting direction is restricted. The bearing mounting portion is formed, for example, in a concave shape continuous with the through hole 61a on the back surface of the second shaft support 60, and the second bearing 64 is fitted into this concave shape. Note that the second bearing 64 is constituted by, for example, a rolling bearing, but may be constituted by a bearing such as a sliding bearing.

[0085] The first shaft support 50 and the second shaft support 60 sandwich the core assembly 40 having the core body K composed of the magnetic pole core 41 and the magnetic path core 42 by the fixing material 32, and are fixed to the core assembly 40, and are integrated as the unit fixing portion 30 of the drive unit 10.

[0086] The second shaft support 60 has a fixing hole 60c as a fixing portion used together with the fixing material 32, together with the first shaft support 50 via the fixing material 32, with the core assembly 40 as a configuration.

[0087] The fixing hole 60c is provided in the support main body 62 at a position corresponding to the fixing hole 503 of the first shaft support portion 50 and the mounting hole 40a of the core assembly 40, that is, at a position facing in the axial direction. In the support main body 62, fixing holes are formed at the four corners respectively, and are formed such that the fixing material 32 is inserted and a part of each of the fixing materials 32, here the flange portion of the head, engages. In addition, when the fixing material 32 is a screw or the like, the support main body 62 is provided with a recess for allowing the screw head (the head of the fixing material 32) to escape, and the fixing hole 60c is disposed in the recess. Thereby, in the support main body 62, even when the shaft of the fixing material 32 such as a bolt or a screw is inserted through the fixing hole 60c and the head of the fixing material 32 is engaged around the fixing hole 60c, the head of the fixing material 32 is allowed to escape and the head does not protrude outward.

[0088] <Unit movable part 20> The magnet 26 is a ring-shaped magnet in which the S pole 26a and the N pole 26b are alternately arranged in the circumferential direction. The magnet 26 is attached to the circumferential surface of the rotating shaft 24 so as to be positioned in the space surrounded by the magnetic poles 411a and 412a of the core body K in a state where the rotary reciprocating drive actuator 1 is assembled. When the coils 44 and 45 are energized, the rod-like bodies 411 and 412 and the magnetic path core 42 are excited to generate polarities corresponding to the energization direction in the magnetic poles 411a and 412a, and a magnetic force (attractive force and repulsive force) is generated between the magnetic poles 411a and 412a and the magnet 26.

[0089] In the present embodiment, the magnet 26 is magnetized with different polarities with a plane along the axial direction of the rotating shaft 24 as a boundary. That is, the magnet 26 is a two-pole magnet magnetized so as to be equally divided into the S pole 26a and the N pole 26b. The number of magnetic poles of the magnet 26 (two in the present embodiment) is equal to the number of magnetic poles 411a and 412a of the core body K. Note that the magnet 26 may be magnetized with two or more poles according to the amplitude during movement. In this case, the magnetic pole portion of the core body K is provided corresponding to the magnetic poles of the magnet 26.

[0090] Also, as shown in FIGS. 3 to 5, the magnet 26 is disposed between the annular spacer 25 and the preload spring 27 between the bearing 54 of the first shaft support 50 and the bearing 64 of the second shaft support 60. Further, the magnet 26 is fixed to the rotating shaft 24. On the rotating shaft 24, a shaft support ring 28 is provided so as to protrude in the radial direction at a portion on the other end side that penetrates the second bearing 64 and protrudes outside the core assembly 40. Specifically, the shaft support ring 28 is attached by being fitted into a notch 246 formed in the rotating shaft 24, and is adjacent to the second bearing 64 on the other end side of the rotating shaft 24.

[0091] When the magnet 26 attaches the rotating shaft 24 to the unit fixing portion 30, in the unit fixing portion 30 in the axial direction, on the other end side of the rotating shaft 24, it is disposed via a spacer 25 between the second bearing 64. On the other hand, on the one end side of the rotating shaft 24, the magnet 26 is disposed in a state where a preload is applied to the spacer side via the preload spring 27 sandwiched between washers 27a, 27a between the magnet 26 and the first bearing 54.

[0092] In this way, the magnet 26 is disposed in a state of being positioned within the unit fixing portion 30. In this state, when an external force is applied to the preload spring 27 in the compression direction of the preload spring 27, the shaft support ring 28 restricts the movement of the rotating shaft 24 and the magnet 26 in the thrust direction (for example, the upper side in FIG. 3) with respect to the unit fixing portion 30. Therefore, in particular, components (such as the encoder disk 74) of the angle sensor unit 70 provided on the other end side of the rotating shaft 24 do not move together with the rotating shaft 24 and collide with other components, such as the second bearing 64, and are not damaged.

[0093] As shown in FIG. 6, the polarity of the magnet 26 is switched at the boundary portions 26c, 26d (hereinafter referred to as “magnetic pole switching portions”) between the S pole 26a and the N pole 26b. The magnetic pole switching portions 26c, 26d face the respective magnetic poles 411a, 412a when the magnet 26 is held in the neutral position.

[0094] In the neutral position, the pole switching portions 26c and 26d of the magnet 26 face the poles 411a and 412a, so that the unit fixing portion 30 can generate the maximum torque and stably drive the movable body.

[0095] Further, by configuring the magnet 26 as a two-pole magnet, it becomes easier to drive the movable object with a high amplitude in cooperation with the core body K, and the driving performance can be improved. In the embodiment, the case where the magnet 26 has a pair of pole switching portions 26c and 26d has been described, but it may have two or more pairs of pole switching portions.

[0096] FIG. 11 is a diagram for explaining the angle sensor device. As shown in FIGS. 1, 4, 5, and 11, the angle sensor unit 70 includes a circuit board 71, an optical sensor 73 mounted on the circuit board 71, an encoder disk 74, and a sensor mounting portion 78. The circuit board 71 is fixed to the sensor mounting portion 78 by an adhesive 33. The sensor mounting portion 78 also functions as a cover that covers the optical sensor 73, and the sensor mounting portion 78 is fixed to the support main body portion 62 of the second axis support 60 by an adhesive 34. The sensor mounting portion 78 covers the optical sensor 73. Thereby, it is possible to prevent the intrusion of impurities such as dust into the optical sensor 73, prevent light interference, and perform stable detection.

[0097] The encoder disk 74 is formed in an annular shape and is fixedly attached to the rotating shaft 24 via a cylindrical portion on the inner peripheral portion, and rotates integrally with the magnet 26 and the mirror portion 22. The encoder disk 74 is provided such that its rotational position is the same as the rotational position of the rotating shaft 24. The optical sensor 73 emits light to the encoder disk 74 and detects the rotational position (angle) of the encoder disk 74 based on the reflected light. Thereby, the rotational positions of the magnet 26 and the mirror portion 22 can be detected by the optical sensor 73.

[0098] In the rotary reciprocating drive actuator 1 of the present embodiment, the mirror unit 22 has a drive unit 10 that is driven to reciprocate rotationally by a rotation shaft 24. The drive unit 10 includes a magnet 26, a unit movable part 20 having a rotation shaft 24 connected to the mirror unit 22, and a unit fixed part 30 having a first shaft support 50, a core assembly 40, and a second shaft support 60.

[0099] In the unit fixed part 30, the mirror unit 22 is supported by the rotation shaft 24 protruding from the first shaft support 50 side, and an angle sensor unit 70 for detecting the rotation angle of the rotation shaft 24 protruding from the second shaft support 60 side is provided on the second shaft support 60. The angle sensor unit 70 is attached to the outer surface side of the second shaft support 60 straddling the second shaft support 60 and the rotation shaft 24.

[0100] The angle sensor unit 70 can detect the rotation angle of a movable body including the magnet 26 and the rotation shaft 24, and controls the rotation angle position and rotation speed of the movable body during driving, specifically, the mirror unit 22 which is the movable object.

[0101] The optical sensor 73 of the angle sensor unit 70 is attached to a sensor attachment part 78 attached to the second shaft support 60. By simply removing the sensor attachment part 78 from the second shaft support 60, the optical sensor 73 can be easily removed. Note that a substrate 79 for the drive power supply of the vibration actuator 1 is attached to the sensor attachment part 78. Coils 44 and 45 are connected to this substrate 79, and power is supplied to the coils 44 and 45.

[0102] This enables easy replacement in case of a problem with the angle sensor unit 70. Also, it becomes possible to assemble the angle sensor unit 70 at the final stage of assembly. As a result, since the expensive angle sensor unit 70 can be assembled after confirming that the assembly of other parts is normal, the risk of wasting the expensive angle sensor unit 70, particularly the optical sensor 73, due to defective assembly of other parts can be suppressed. Also, even if there is a problem with the actuator after installation, the optical sensor 73 can be immediately removed by removing the sensor mounting portion 78.

[0103] FIG. 12 is a perspective view showing the stopper. At one end of the rotary shaft 24 opposite to the end to which the mirror unit 22 is connected, a stopper portion 75 that protrudes from the sensor mounting portion 78 and restricts the rotation of the rotary shaft 24 is provided. A protrusion 76 that protrudes in the radial direction is provided on the stopper portion 75. A restricting portion 77 is disposed within the rotation range of the protrusion 76 on the outer surface of the sensor mounting portion 78. When the stopper portion 75 rotates, the rotation range thereof is restricted by the protrusion 76 coming into contact with the restricting portion 77. This limits the maximum rotation angle of the rotary shaft 24, prevents interference with other parts, and can prevent deformation and damage due to interference.

[0104] Next, the operation of the reciprocating rotary drive actuator 1 will be described with reference to FIGS. 6, 13, and 14. FIGS. 13 and 14 are diagrams for explaining the operation of the magnetic circuit of the rotary reciprocating drive actuator 1 and show the magnetic circuit configuration based on the cross-sectional view taken along line B-B in FIG. 3.

[0105] The two magnetic poles 411a and 412a of the core body K of the core assembly 40 are arranged with the magnet 26 interposed therebetween with an air gap G. When no current is supplied to the coils 44 and 45, as shown in FIG. 3, the magnet 26 is held in the neutral position by the magnetic attraction force between the magnet 26 and the rotation angle position holding portion 48.

[0106] In this neutral position, one of the S pole 26a and the N pole 26b of the magnet 26 (the S pole 26a in FIG. 13) is attracted to the rotation angle position holding portion 48 (see the magnetic spring torque FM in FIG. 13 and the magnetic spring torque -FM in FIG. 14). At this time, the magnetic pole switching portions 26c and 26d face the central positions of the magnetic poles 411a and 412a of the core body K.

[0107] When the coils 44 and 45 are energized, the core body K is excited, and polarities corresponding to the energization directions are generated in the magnetic poles 411a and 412a. As shown in FIG. 13, when the coils 44 and 45 are energized, magnetic flux is generated inside the core body K, the magnetic pole 411a becomes an S pole, and the magnetic pole 412a becomes an N pole. As a result, the magnetic pole 411a magnetized to the S pole attracts the N pole 26b of the magnet 26, and the magnetic pole 412a magnetized to the N pole attracts the S pole 26a of the magnet 26. Then, a torque in the F direction is generated around the axis of the rotation shaft 24 on the magnet 26, and the magnet 26 rotates in the F direction. Along with this, the rotation shaft 24 also rotates in the F direction, and the mirror unit 22 fixed to the rotation shaft 24 also rotates in the F direction.

[0108] Next, as shown in FIG. 14, when the coils 44 and 45 are energized in the reverse direction, the flow of the magnetic flux generated inside the core body K becomes the reverse direction, the magnetic pole 411a becomes an N pole, and the magnetic pole 412a becomes an S pole. The magnetic pole 411a magnetized to the N pole attracts the S pole 26a of the magnet 26, and the magnetic pole 412a magnetized to the S pole attracts the N pole 26b of the magnet 26. Then, a torque -F opposite to the F direction is generated around the axis of the rotation shaft 24 on the magnet 26, and the magnet 26 rotates in the -F direction. Along with this, the rotation shaft 24 also rotates, and the mirror unit 22 fixed to the rotation shaft 24 also rotates. The rotational reciprocating drive actuator 1 repetitively performs the above operations to rotationally reciprocate the mirror unit 22.

[0109] In practice, the rotary reciprocating drive actuator 1 is driven by an alternating current wave input to coils 44 and 45 from a power supply unit (corresponding to the drive signal supply unit 103 in FIG. 17, for example). That is, the energization directions of coils 44 and 45 are periodically switched. When the energization direction is switched, the magnetic attraction force between the rotation angle position holding unit 48 and the magnet 26, that is, the restoring force of the magnetic spring (magnetic spring torques FM and -FM shown in FIGS. 13 and 14), biases the magnet 26 to return to the neutral position. As a result, torques in the F direction and in the direction opposite to the F direction (-F direction) act on the movable body alternately about the axis. Thereby, the movable body is driven to rotate reciprocally.

[0110] The driving principle of the rotary reciprocating drive actuator 1 will be briefly described below. In the rotary reciprocating drive actuator 1 of the present embodiment, the moment of inertia of the movable body (movable body) is J [kg·m 2 , and when the torsional spring constant of the magnetic spring (magnetic poles 411a, 412a, rotation angle position holding unit 48, and magnet 26) is K sp , the movable body vibrates (rotates reciprocally) at a resonance frequency F r [Hz] calculated by Equation (1) with respect to the fixed body (unit fixing portion 30).

[0111]

Equation

[0112] Since the movable body constitutes the mass part in the vibration model of the spring-mass system, when an alternating current wave having a frequency equal to the resonance frequency F r of the movable body is input to coils 44 and 45, the movable body enters a resonance state. That is, by inputting an alternating current wave having a frequency approximately equal to the resonance frequency F r of the movable body from the power supply unit to coils 44 and 45, the movable body can be vibrated efficiently.

[0113] The motion equation and circuit equation showing the driving principle of the rotary reciprocating drive actuator 1 are shown below. The rotary reciprocating drive actuator 1 is driven based on the motion equation shown in Equation (2) and the circuit equation shown in Equation (3).

[0114] [Number]

[0115] [Number]

[0116] That is, the moment of inertia J [kg·m 2 , the rotation angle θ(t) [rad], the torque constant K t [N·m / A], the current i(t) [A], the spring constant K sp [N·m / rad], the damping coefficient D [N·m / (rad / s)], the load torque T Loss [N·m], etc. can be appropriately changed within the range that satisfies Equation (2). Also, the voltage e(t) [V], the resistance R [Ω], the inductance L [H], and the back electromotive force constant K e [V / (rad / s)] can be appropriately changed within the range that satisfies Equation (3).

[0117] Thus, when the coil is energized by an alternating current corresponding to the resonance frequency F sp determined by the moment of inertia J of the movable body and the spring constant K r of the magnetic spring in the rotary reciprocating drive actuator 1, a large vibration output with high efficiency can be obtained.

[0118] (Modification Example 1) FIG. 15 is an external perspective view of the rotary reciprocating drive actuator of Modification Example 1, and FIG. 16 is a front-side exploded perspective view of the rotary reciprocating drive actuator.

[0119] The rotary reciprocating drive actuator 1A shown in FIGS. 15 and 16 is a rotary reciprocating drive actuator that supports a movable object in a reciprocating rotary motion, such as when the movable object is enlarged, compared to the rotary reciprocating drive actuator 1.

[0120] The rotary reciprocating drive actuator 1A has an auxiliary frame 80 compared to the rotary reciprocating drive actuator 1, the configuration of the first shaft support 50A to which the auxiliary frame 80 is attached is different, and the length of the rotary shaft 24A is different, while other configurations are the same. Therefore, below, for the rotary reciprocating drive actuator 1A, only the different configurations will be described compared to the rotary reciprocating drive actuator 1, and the descriptions of the same configurations will be omitted.

[0121] The rotary reciprocating drive actuator 1A has the same function as the rotary reciprocating drive actuator 1 and includes a drive unit 10A, a mirror unit 22A, an auxiliary frame 80, and an angle sensor unit 70.

[0122] The drive unit 10A has a different configuration of the first shaft support 50 in the unit fixing portion 30 compared to the drive unit 10. In the drive unit 10A, the top surface of the support main body portion 52A of the first shaft support 50A in the unit fixing portion 30A has a frame fixing surface 57 to which one side wall portion 81a of the pair of wall portions 81a, 81b of the auxiliary frame 80 is fixed.

[0123] The auxiliary frame 80 is fixed to the frame fixing surface 57 via a fixing material 36. The drive unit 10A has a longer rotary shaft 24A in the unit movable portion 20 compared to the drive unit 10, and the core assembly 40 is sandwiched between the first shaft support 50A and the second shaft support 60. The rotary shaft 24A has a length that spans between the wall portions 81a, 81b of the auxiliary frame 80 and is arranged to extend from the communication hole 82b to the communication hole 82a.

[0124] The rotary reciprocating drive actuator 1A attaches an auxiliary frame 80 to a drive unit 10A to support a mirror unit 22A, which is a movable object, so as to be reciprocally rotatable.

[0125] The auxiliary frame 80 is a member having a substantially U-shaped cross section with a pair of wall portions 81a and 81b. Insertion holes 82a and 82b through which a rotary shaft 24A is inserted are formed in the pair of wall portions 81a and 81b, respectively. A rotary support portion 39 into which the tip of the rotary shaft 24A is rotatably inserted is fitted in the communication hole 82a. Further, notch holes 83a and 83b that communicate the insertion holes 82a and 82b with the outer edges of the wall portions 81a and 81b are formed in the pair of wall portions 81a and 81b, respectively.

[0126] The rotary support portion 39 may be configured in any way as long as it rotatably supports the inserted rotary shaft 24A, and may be configured with a sliding bearing, a bush made of resin, or the like. The rotary support portion 39 supports the tip portion 242 of the rotary shaft 24A to which the mirror unit 22A is attached between the pair of wall portions 81a and 81b of the auxiliary frame 80.

[0127] Thereby, with the mirror unit 22A fixed to the rotary shaft 24A, the rotary shaft 24A can be disposed at the position of the rotary shaft 24A through the notch holes 83a and 83b. Further, the rotary shaft 24A is disposed between the wall portions 81a and 81b of the auxiliary frame 80.

[0128] If there are no notch holes 83a and 83b, a complicated assembly operation is required, such as inserting the rotary shaft 24A through both of the insertion holes 82a and 82b of the wall portions 81a and 81b with the mirror unit 22A disposed between the pair of wall portions 81a and 81b and then fixing the rotary shaft 24A and the mirror unit 22A. In contrast, in the present embodiment, since the notch holes 83a and 83b are formed, the rotary shaft 24A to which the mirror unit 22A is fixed in advance can be easily inserted into the insertion holes 82a and 82b.

[0129] According to this configuration, even when the movable object becomes larger, that is, when the mirror unit 22A is supported by the drive unit 10A with a cantilever structure, the behavior of the mirror unit 22A can be stabilized, impact resistance and vibration characteristics can be ensured, and it can be stably supported so as to be reciprocally rotatable.

[0130] FIG. 17 is a block diagram showing a main part configuration of a scanner system 100 using a rotary reciprocating drive actuator 1.

[0131] In addition to the rotary reciprocating drive actuator 1, the scanner system 100 includes a laser light emitting unit 101, a laser control unit 102, a drive signal supply unit 103, and a position control signal calculation unit 104.

[0132] The laser light emitting unit 101 includes, for example, an LD (laser diode) serving as a light source, a lens system for converging the laser light output from this light source, and the like. The laser control unit 102 controls the laser light emitting unit 101. The laser light irradiated from the laser light emitting unit 101 is incident on the mirror 221 of the rotary reciprocating drive actuator 1.

[0133] The position control signal calculation unit 104 refers to the angular position of the rotation axis 24 (mirror 221) acquired by the angle sensor unit 70 and the target angular position, and generates and outputs a drive signal for controlling the rotation axis 24 (mirror 221) to reach the target angular position. For example, the position control signal calculation unit 104 generates a position control signal based on the acquired angular position of the rotation axis 24 (mirror 221) and a signal indicating the target angular position converted using, for example, sawtooth waveform data stored in a waveform memory (not shown), and outputs this position control signal to the drive signal supply unit 103.

[0134] Based on the position control signal, the drive signal supply unit 103 supplies a drive signal to the coils 44 and 45 of the rotary reciprocating drive actuator 1 such that the angular position of the rotation axis 24 (mirror 221) becomes a desired angular position. Thereby, the scanner system 100 can emit scanning light from the rotary reciprocating drive actuator 1 to a predetermined scanning area.

[0135] <Summary> As described above, the rotational reciprocating drive actuator 1 according to the present embodiment includes a movable part 20 having a rotating shaft (shaft part) 24 to which a mirror part (object to be moved) is connected and a magnet 26 fixed to the rotating shaft 24. The magnet 26 is a ring-shaped magnet in which S poles 26a and N poles 26b are alternately arranged in the circumferential direction on the outer peripheral surface.

[0136] In addition, the rotational reciprocating drive actuator 1 has a unit fixing part 30. The unit fixing part 30 has a core assembly 40 including a core body K having a plurality of magnetic poles 411a, 412a and a plurality of coils 4, 45 that generate magnetic flux in the core body K when energized. The unit fixing part 30 arranges the core assembly 4 such that the plurality of magnetic poles 411a, 412a face the outer periphery of the magnet 26 and the plurality of coils 44, 45 are parallel to each other.

[0137] On both sides of the core assembly 40 in the extending direction of the rotating shaft 24, a first shaft support 50 and a second shaft support 60, which are a pair of shaft supports that rotatably support the rotating shaft 24, are provided. These pair of shaft supports 50, 60 sandwich and fix the core assembly 40, and reciprocally rotate the movable part 20 around the axis of the rotating shaft 24 by the electromagnetic interaction between the magnetic flux and the magnet 26.

[0138] In this way, the mirror part 22, which is the object to be moved, is rotatably supported by both of the pair of shaft support parts 50, 60 that sandwich and fix the core assembly 40, and is reciprocally rotatably supported via the rotating shaft 24 protruding from the unit fixing part 30 to one side. Thereby, in the rotational reciprocating drive actuator 1, even if it is cantilevered, the mirror part 22 can be reliably and stably supported so as to be movable via the rotating shaft 24.

[0139] That is, in the unit fixing portion 30, the portion where the magnet 26 of the rotating shaft 24 is disposed is supported at two points with the core assembly 40 sandwiched between the first shaft support 50 and the second shaft support 60. Thereby, even if the magnetic attraction force between the magnet 26 and the rotation angle position holding portion 48 increases, the linearity of the rotating shaft 24 can be ensured. That is, when the portion where the magnet 26 of the rotating shaft 24 is disposed is supported only by the second shaft support 60 and is cantilevered, if the magnetic attraction force between the magnet 26 and the rotation angle position holding portion 48 increases, the rotating shaft 24 may bend toward the rotation angle position holding portion 48 and the linearity may deteriorate, but such a problem does not occur.

[0140] Thus, according to the rotary reciprocating drive actuator 1, it is possible to achieve further miniaturization and smaller space, has impact resistance and vibration resistance characteristics, and can drive a movable object via a shaft portion in a more stable state and with a high amplitude.

[0141] In addition, similar to the first shaft support 50, even in a configuration where the first shaft support 50A having a configuration substantially the same as the first shaft support 50 and the tip of the rotating shaft 24 are separated from the first bearing 54, it can be preferably supported by the auxiliary frame 80 and the rotation support portion 39.

[0142] Since the core body K is configured as a separate body of the magnetic pole core 41 and the magnetic path core 42, and in the magnetic pole core 41, the magnetic poles 411a and 412a are integrally structured at positions facing the outer periphery of the magnet 26, even if the shape of the core body K having the magnetic pole core 41 and the magnetic path core 42 is complicated, it can be easily manufactured without reducing the arrangement accuracy of the plurality of magnetic poles 411a and 412a.

[0143] Note that the number of magnetic poles of the magnet 26 is equal to the number of magnetic poles 411a and 412a. The unit fixing portion 30 has a rotation angle position holding portion (magnet position holding portion) 48 provided to face the magnet 26 with an air gap G therebetween. The rotation angle position holding portion 48 holds the magnet 26 at a reference position, that is, the rotation angle position of the rotation axis 24 or the magnet 26 at the neutral position, by the magnetic attraction force generated therebetween. The reference position is the rotation center position of the reciprocating rotation of the magnet 26.

[0144] By switching the energization directions to the plurality of coils 44 and 45, the flow of magnetic flux passing through the integrally structured magnetic pole core 41 and magnetic path core 42 is switched to be generated in the core assembly 40, and due to the electromagnetic interaction between the magnetic flux and the magnet 26, the movable body reciprocally rotates about the axis of the rotation axis 24.

[0145] Since the magnetic pole core 41 and the magnetic path core 42 are laminated members, they are not troublesome to manufacture, and magnetic pole cores 41 and magnetic path cores 42 having a complicated shape can be configured at low cost. The magnetic pole core 41 has, in an integral structure, a plurality of rod-shaped bodies 411 and 412, and a connection frame-shaped body 413 connecting the plurality of rod-shaped bodies 411 and 412 to each other. The plurality of rod-shaped bodies 411 and 412 each have a plurality of magnetic poles 411a and 412a at their tip portions, extend parallel to each other from the base end portions 411b and 412b to the tip portions, and a plurality of coils 44 and 45 are respectively externally mounted at the intermediate portions. The connection frame-shaped body 413 extends in a direction intersecting the parallel direction of the rod-shaped bodies 411 and 412 at the base end portions 411b and 412b.

[0146] The magnetic path core 42 faces the connection frame-shaped body 413 in the extending direction of the rotation axis 24 and is in surface contact with each other, and positions a plurality of magnetic poles 411a and 412a in a stable state with the coils 44 and 45 adjacent to each other around the rotation axis 24, so that the magnetic pole core 41 is assembled.

[0147] Accordingly, even for a core having magnetic poles 411a and 412a arranged to face each other with the magnet 26 therebetween, it is possible to achieve high output while reducing the manufacturing cost, improve the arrangement accuracy of the magnetic poles 411a and 412a, and arrange them without variation. Therefore, the reliability of the rotary reciprocating drive actuator 1 can be improved.

[0148] In addition, the magnetic circuit core 42 has extension portions (side portions 421 and 422, bridging portion 423) that extend outside the rod-shaped bodies 411 and 412, and the extension portions are arranged around the rotary shaft 24 so as to surround the coils 44 and 45 together with the connecting frame-shaped body 413. Thereby, it is possible to suppress the electromagnetic noise generated from the energized coils 44 and 45, further suppress the leakage magnetic flux from the coils 44 and 45 and the magnet 26, and prevent the electromagnetic influence on external devices.

[0149] Also, if the rotational angle position holding portion 48 is a magnet, when the movable body is reciprocally rotated, the movable body can be positioned more accurately at the reference position of the movable body and reciprocally driven from that position, and can be reliably reciprocally driven.

[0150] In addition, the movable object is a mirror portion 22 (particularly the mirror 221) that reflects the scanning light. Thereby, the rotary reciprocating drive actuator 1 can be used for the application of a scanner that performs optical scanning.

[0151] As described above, the invention made by the present inventor has been specifically described based on the embodiments, but the present invention is not limited to the above embodiments and can be modified without departing from the gist thereof.

[0152] For example, in the embodiment, the case where the movable object is the mirror portion 22 has been described, but the movable object is not limited to this. The movable object may be, for example, an imaging device such as a camera.

[0153] For example, in the embodiment, the case where the rotary reciprocating drive actuator 1 is resonantly driven has been described, but the present invention can also be applied to the case of non-resonant drive.

[0154] Also, the configuration of the unit fixing portion 30 is not limited to that described in the embodiment. For example, the core has a magnetic pole portion that is excited by energizing the coil to generate a polarity, and when the rotating shaft is attached to the unit fixing portion, it is only necessary that the magnetic pole portion and the outer peripheral surface of the magnet face each other with an air gap therebetween. Further, the coil only needs to have a configuration that preferably generates magnetic flux from one of the magnetic pole portions of the core to the other when energized.

[0155] The embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and it is intended that all modifications within the meaning and scope equivalent to the claims are included.

Industrial Applicability

[0156] The present invention is suitable for, for example, LiDAR devices, scanner systems, and the like.

Explanation of Reference Numerals

[0157] 1, 1A Rotary reciprocating drive actuator 10, 10A Drive unit 20 Unit movable part 22, 22A Mirror part 24, 24A Rotating shaft 25 Spacer 26 Magnet 26a, 26b Pole 26c, 26d Boundary part (magnetic pole switching part) 27 Preload spring 27a Washer 28 Shaft support ring 30, 30A Unit fixing portion 32, 33, 34, 36 Adhesive 39 Rotational support portion 40-core assembly 40a mounting hole 40b engaging recess 40c, 40d, 40e, 60a, 60b, 501, 502 positioning holes 41 pole core 42 magnetic path core 44, 45 coils 46, 47 bobbins 48 angular position holding part 50, 50A first shaft support 51a, 61a through holes 52, 52A, 62 support body parts 54 first bearing (bearing part) 56 mounting leg 57 frame fixing surface 58 core holding part 60 second shaft support 64 second bearing (bearing part) 70 angle sensor part 71 circuit board 73 optical sensor 74 encoder disk 75 stopper part 76 protrusion 77 regulating part 78 sensor mounting part 79 board 80 auxiliary frame 81a, 81b wall parts 82a, 82b insertion holes 83a, 83b notch holes 100 scanner system 101 laser emitting part 102 laser control part 103 signal supply part 104 signal calculation part 221 mirror 222 mirror holder 223 insertion hole 242 tip 242a cut surface 411, 412 rod-like bodies 411a, 412a poles Base end portions of 411b, 412b, 421b, and 422b 413 Connection frame body 413a Connection side portion 413b, 413c Protruding side portions 420 Enclosing portion 420a Magnetic path side contact surface 420b Notch portion 421, 422 Side portions 423 Bridging portion 424 Magnetic path side connection side portion Anchoring holes 503, 60c Through holes 521, 62a 4130 Magnetic pole side contact surface K-core body

Claims

1. A movable body having a shaft portion to which a movable object is connected and a magnet fixed to the shaft portion, A fixed body having a core assembly including a core body having a plurality of magnetic poles and a plurality of coils, and arranging the core assembly with the plurality of magnetic poles facing the outer periphery of the magnet, A pair of shaft supports that sandwich the core assembly in the extending direction of the shaft portion and rotatably support the shaft portion on both sides of the core assembly, having, By energizing the plurality of coils, a magnetic flux passing through the core body is generated, and the movable body is reciprocally rotated around the axis of the shaft portion by the electromagnetic interaction between the magnetic flux and the magnet, The core body is, A magnetic pole core having an integrated structure including the plurality of magnetic poles, A magnetic path core that forms a magnetic path of the magnetic flux together with the magnetic pole core, having, and the magnetic pole core and the magnetic path core are assembled to each other by being sandwiched by the shaft support in a state of facing each other and in surface contact in the extending direction of the shaft portion, A rotary reciprocating drive actuator.

2. The magnetic path core is assembled with the magnetic pole core in a state where the plurality of magnetic poles are positioned around the shaft portion, The rotary reciprocating drive actuator according to claim 1.

3. At least one of the pair of shaft supports is provided so as to protrude inside the core assembly, and has a core holding portion that intervenes between the plurality of magnetic poles and the magnetic path core and holds the positions of both, The rotary reciprocating drive actuator according to claim 1 or 2.

4. The fixed body is a magnetic body disposed to face the magnet, and has a magnet position holding portion that magnetically attracts the magnet to a reference position, The rotary reciprocating drive actuator according to any one of claims 1 to 3.

5. The reference position at which the magnet position holding portion magnetically attracts the magnet is the rotation center position of the reciprocating rotation of the magnet, The rotary reciprocating drive actuator according to claim 4.

6. The plurality of magnetic poles are respectively formed at the tip portions of a pair of rod-shaped bodies arranged in parallel in the core body, The plurality of coils are respectively arranged on each of the pair of rod-shaped bodies adjacent to each of the plurality of magnetic poles, The rotary reciprocating drive actuator according to any one of claims 1 to 5.

7. Each of the pair of shaft supports includes a bearing portion into which the shaft portion is inserted and a support body main portion formed of an electromagnetic shielding material that covers the core assembly in the extending direction of the shaft portion. The rotary reciprocating drive actuator according to any one of claims 1 to 6.

8. The electromagnetic shielding material contains an aluminum alloy. The rotary reciprocating drive actuator according to claim 7.

9. The core body is composed of a laminated member. The rotary reciprocating drive actuator according to any one of claims 1 to 8.

10. The pair of shaft supports includes a first shaft support and a second shaft support. The movable object is disposed on the side opposite to the core assembly with respect to the first shaft support. An angle sensor for detecting the rotation angle of the shaft portion is disposed on the side opposite to the core assembly with respect to the second shaft support. The rotary reciprocating drive actuator according to any one of claims 1 to 9.

11. It has a cover attached to the second shaft support so as to cover the angle sensor. The rotary reciprocating drive actuator according to claim 10.

12. One end of the shaft portion protruding from the first shaft support among the pair of shaft supports is connected to the movable object. A rotary support shaft portion fixed to a support wall portion disposed so as to sandwich the movable object with the first shaft support is provided at the tip of the movable object fixed to one end of the shaft portion. The rotary reciprocating drive actuator according to any one of claims 1 to 11.

13. The rotary support shaft portion is a sliding bearing. The rotary reciprocating drive actuator according to claim 12.

14. The rotary support shaft portion is a bush made of resin. The rotary reciprocating drive actuator according to claim 12.

15. It has a rotation angle restricting portion that restricts the maximum rotation angle when the shaft portion rotates and reciprocates with respect to the core assembly. The rotary reciprocating drive actuator according to any one of claims 1 to 14.

16. The core assembly is provided with a positioning portion that defines the positions of the pair of shaft supports that sandwich the core assembly. The rotary reciprocating drive actuator according to any one of claims 1 to 15.

17. The movable object is a mirror that reflects scanning light. The rotary reciprocating drive actuator according to any one of claims 1 to 16.

18. A movable body having a shaft portion to which a movable object is connected and a magnet fixed to the shaft portion. A core assembly comprising: a pair of parallel rod-shaped bodies each having a plurality of magnetic poles disposed opposite to the outer periphery of the magnet at their respective tip portions, and a plurality of coils are respectively disposed thereon; and a rectangular frame-shaped body surrounding the pair of rod-shaped bodies, wherein a base end portion of the pair of rod-shaped bodies is connected to form a surrounding portion that constitutes a magnetic path connecting between the plurality of magnetic poles. A pair of shaft supports that sandwich the core assembly in the extending direction of the shaft portion and rotatably support the shaft portion on both sides of the core assembly. having By energizing the plurality of coils, a magnetic flux passing through the pair of rod-shaped bodies and the surrounding portion is generated, and the movable body is reciprocally rotated around the axis of the shaft portion by an electromagnetic interaction between the magnetic flux and the magnet. A rotary reciprocating drive actuator.

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