Rotary and reciprocating actuator

Abstract

To drive reciprocating rotation of a movable body with high amplitude in a more stable state by a simple configuration.SOLUTION: A rotation reciprocating drive actuator comprises: a movable body having a magnet fixed to a shaft part with which a movable object is connected and reciprocatingly and rotatably arranged centering on the shaft part; and a fixed body in which a plurality of magnetic poles having a plurality of coils, a first magnetic attraction member which generates first magnetic attraction force for regulating a rotation center position of reciprocating rotation of the movable body between itself and the magnet, and a second magnetic attraction member which generates second magnetic attraction force for cancelling axial and radial loads acting on the movable body by the first magnetic attraction force between itself and the magnet are arranged by being opposed to each other on an outer periphery of the magnets, wherein magnetic fluxes passing through the plurality of magnetic poles are generated by energization to the plurality of coils, so as to reciprocatingly rotate the movable body around the shaft part on the basis of the rotation center position by an electromagnetic interaction between the magnetic fluxes and the magnet.SELECTED DRAWING: Figure 5

Description

[Technical Field]

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

[0002] Conventionally, rotary actuators have been used as actuators for scanners in multifunction peripherals, laser beam printers, etc. Specifically, rotary reciprocating actuators rotate the mirror of the scanner back and forth to change the reflection angle of the laser light, thereby achieving optical scanning of the target object.

[0003] A galvanometer motor is used as this type of rotary reciprocating drive actuator, as disclosed in Patent Document 1. There are various types of galvanometer motors known, including those with the structure disclosed in Patent Document 1 and movable coil types in which the coil is attached to a mirror.

[0004] Patent document 1 discloses a beam scanner in which four permanent magnets are arranged 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 a moving coil type rotary reciprocating actuator, heat generated by the coil during operation can have adverse effects on the surface condition of the mirror, the bonding state of the mirror to the rotation axis, and the shape of the mirror, including warping. Furthermore, in a moving coil type rotary reciprocating actuator, taking into account the heat generated by the coil when current is applied, it is difficult to increase the input current to the coil, making it difficult to increase the size and amplitude of the mirror, which is the moving body. Furthermore, wiring to the coil must be drawn to the fixed body side of the mirror, which is the moving body, making assembly difficult.

[0007] In this regard, in Patent Document 1, the magnet is arranged on the movable body side, which solves the above-mentioned problem with the movable coil type. On the other hand, in this configuration, in order to appropriately position the magnet at the center of reciprocating rotation relative to the core, that is, to position the switching point of the magnetic poles of the magnet at the center of the core, two magnet poles are provided for one core pole. In this way, in Patent Document 1, a total of four magnet poles are positioned around the shaft with a predetermined interval between them.

[0008] Therefore, there is a problem that the amplitude of the movable body is smaller, that is, the oscillation range is reduced, compared to when a two-pole magnet is used to configure a rotary reciprocating drive actuator similar to that of Patent Document 1. Also, because at least four magnets are used on the movable body side, the configuration is complex with a large number of parts, making assembly difficult.

[0009] The present invention has been made in consideration of the above points, and provides a rotary reciprocating drive actuator that can drive the reciprocating rotation of a movable body with a simple configuration, in a more stable state, and with a high amplitude. [Means for solving the problem]

[0010] One embodiment of the rotary reciprocating drive actuator of the present invention comprises: a movable body having a magnet fixed to a shaft portion to which a movable object is connected, the movable body being arranged so as to be rotatable back and forth around the shaft portion; Multiple coilsand Multiple magnetic poles A core body having a fixed body arranged on the outer periphery of the magnet to face a first magnetic attraction member that generates, between itself and the magnet, a first magnetic attraction force that defines the rotation center position of the reciprocating rotation of the movable body, and a second magnetic attraction member that generates, between itself and the magnet, a second magnetic attraction force that offsets the axial radial load acting on the movable body due to the first magnetic attraction force; and By energizing the plurality of coils, a magnetic flux passing through the plurality of magnetic poles is generated, and the movable body is rotated back and forth around the axis of the shaft portion with the rotation center position as a reference by electromagnetic interaction between the magnetic flux and the magnet. 、 The core body is a plurality of rod-shaped bodies each having the plurality of magnetic poles at a tip end portion facing the magnet, extending parallel to one another from a base end portion to the tip end portion, and each having the plurality of coils exteriorly mounted at an intermediate portion thereof; The second magnetically attractive member is disposed parallel to the rod-shaped bodies and extends between the rod-shaped bodies, and is disposed on the opposite side of the first magnetically attractive member with respect to the center of the shaft portion. The configuration is as follows. [Effects of the Invention]

[0011] According to the present invention, the movable body can be driven to rotate back and forth in a more stable manner with a simple configuration and at a high amplitude. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is an external perspective view of a rotary reciprocating actuator according to a first embodiment. [Figure 2] FIG. 2 is a longitudinal sectional view of the drive unit of the rotary reciprocating actuator. [Figure 3] FIG. 2 is an exploded perspective view of the rotary reciprocating actuator from the top side. [Figure 4] FIG. 2 is an exploded perspective view of the bottom surface of the rotary reciprocating actuator. [Figure 5] FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. [Figure 6] FIG. 2 is a bottom perspective view of the core assembly. [Figure 7] FIG. [Figure 8] FIG. [Figure 9]FIG. 10 is a bottom perspective view of a first modified example of the core assembly. [Figure 10] FIG. 10 is a cross-sectional plan view showing the configuration of a main part of a first modified example of the core assembly. [Figure 11] FIG. 10 is a bottom perspective view of a core body in a first modified example of the core assembly. [Figure 12] FIG. [Figure 13] 3 is a diagram illustrating the magnetic attraction force of the rotary reciprocating actuator according to the first embodiment. FIG. [Figure 14] 2 is a diagram illustrating a magnetic circuit of the rotary reciprocating actuator of the first embodiment when not energized. FIG. [Figure 15] 2 is a diagram illustrating a magnetic circuit of the rotary reciprocating actuator of the first embodiment when power is applied. FIG. [Figure 16] 2 is a diagram illustrating a magnetic circuit of the rotary reciprocating actuator of the first embodiment when power is applied. FIG. [Figure 17] FIG. 10 is an external perspective view of a rotary reciprocating actuator according to a second embodiment. [Figure 18] FIG. 2 is an exploded perspective view of the rotary reciprocating actuator from the top side. [Figure 19] FIG. 2 is an exploded perspective view of the bottom surface of the rotary reciprocating actuator. [Figure 20] FIG. 11 is an external perspective view of a rotary reciprocating actuator according to a third embodiment. [Figure 21] FIG. 2 is an exploded perspective view of the rotary reciprocating actuator from the top side. [Figure 22] FIG. 2 is an exploded perspective view of the bottom surface of the rotary reciprocating actuator. [Figure 23] FIG. 1 is a diagram showing the configuration of a main part of a scanner system using a rotary reciprocating actuator. DETAILED DESCRIPTION OF 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 a rotary reciprocating drive actuator 1 according to the first embodiment, and Fig. 2 is a vertical cross-sectional view of a drive unit 10 of the rotary reciprocating drive actuator 1. Figs. 3 and 4 are an exploded perspective view of the top side and an exploded perspective view of the bottom side of the rotary reciprocating drive actuator 1.

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

[0016] 1 roughly comprises a mirror section 22 and a drive unit 10 that rotatably supports the mirror section 22 and drives it to rotate in a reciprocating manner. The rotary reciprocating actuator 1 further comprises an angle sensor section 70 that is provided in the drive unit 10 and detects the rotation angle position of the mirror section 22.

[0017] <Mirror section 22> The mirror section 22 is a movable object in the rotary reciprocating actuator 1, and is connected to the rotary shaft 24. The mirror section 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 to an insertion hole 223 of the mirror holder 222. A movable magnet (hereinafter simply referred to as "magnet") 26 is fixed to the rotary shaft 24 at a portion where the drive unit 10 is inserted and disposed within a unit fixing portion 30 of the drive unit 10. The magnet 26 is driven to rotate and reciprocate by a magnetic flux generated by the unit fixing portion 30, which will be described later.

[0018] <Drive unit 10> As shown in FIGS. 1 to 4, the drive unit 10 includes a unit moving part 20 having a rotation shaft 24 and a magnet 26, and a unit fixing part 30 having coils 44, 45 and driving the unit moving part 20 to rotate back and forth.

[0019] The drive unit 10 supports the mirror section 22 with a rotation shaft 24 that protrudes from a cube-shaped unit fixing section 30, and drives the mirror section 22 to rotate back and forth via the rotation shaft 24. The unit fixing section 30 may be of any shape, such as a columnar shape, or may be a rectangular parallelepiped shape. In this embodiment, the unit fixing section 30 is cube-shaped, so that the installation space can be reduced and it can be installed in a space-saving manner, such as in a corresponding cubic gap.

[0020] In the drive unit 10, the rotation shaft 24 is inserted through the unit fixing part 30 and is supported so as to be freely rotatable back and forth with both ends protruding from the unit fixing part 30. The rotation shaft 24 is connected to the mirror part 22 and the angle sensor part 70 at both ends protruding from the drive unit 10.

[0021] The drive unit 10 constitutes a compactly packaged unit that rotates a rotary shaft 24 back and forth around its axis, and by simply connecting the rotary shaft 24 to a movable object, the movable object can be rotated back and forth with a compact configuration. The unit movable part 20, together with the mirror part 22, constitutes the movable body of the rotary reciprocating drive actuator 1.

[0022] <Unit fixing part 30> 2 and 3, the unit fixing part 30 constitutes the parts of the drive unit 10 other than the unit moving part 20 (for example, parts other than the rotation shaft 24 and the magnet 26). The unit moving part 20 will be described in detail later.

[0023] The unit fixing portion 30 constitutes a fixed body of the rotary reciprocating drive actuator 1 . FIG. 5 is a cross-sectional view taken along line AA in FIG. 2, showing the main configuration of the core assembly in the rotary reciprocating drive actuator 1. As shown in FIG.

[0024] As shown in Figures 2 to 5, the unit fixing part 30 houses the magnet 26 of the unit moving part 20 therein and has a core assembly 40 from which the rotation shaft 24 of the unit moving part 20 rotatably protrudes, a first shaft support 50, and a second shaft support 60.

[0025] The unit fixing portion 30 is constructed by clamping the core assembly 40 between a first shaft support 50 and a second shaft support 60 on both sides in the extension direction of the rotating shaft 24, and fixing the first shaft support 50 and the second shaft support 60 to the core assembly 40.

[0026] The unit fixing portion 30 fixes the first shaft support 50, the core assembly 40, and the second shaft support 60 together via a fastening material 32. In the unit fixing portion 30, the first shaft support 50 and the second shaft support 60 completely cover both end faces of the core assembly 40 from which both ends of the rotating shaft 24 of the unit movable portion 20 protrude.

[0027] In the unit fixing section 30, the mirror section 22 is supported by a rotation axis 24 protruding from the first axis support 50 side, and an angle sensor section 70 is provided on the second axis support 60 to detect the rotation angle of the rotation axis 24 protruding from the second axis support 60 side.

[0028] <Core assembly 40> 6 and 7 are diagrams for explaining the core assembly of the rotary reciprocating drive actuator, where FIG. 6 is a bottom perspective view of the core assembly and FIG. 7 is a bottom perspective view of the core body of the core assembly.

[0029] The core assembly 40 forms a magnetic circuit together with the magnet 26 (see Figures 3 to 5), and has coils 44, 45, a core body K around which the coils 44, 45 are wound, and a rotational angle position holding portion 48 (an example of a first magnetic attraction member).

[0030] The core assembly 40 (more specifically, the core body K) has a plurality of magnetic poles 411a, 412a, is rectangular in shape, and has a frame-shaped outer peripheral portion formed to surround the magnetic poles 411a, 412a arranged inside the outer peripheral portion.

[0031] <Core Body K> FIG. 7 is a bottom perspective view of the core body, and FIG. 8 is an exploded view of the core body. 7 and 8, in this embodiment, the core body K is constructed by combining two divided bodies in the axial direction, that is, in the thickness direction of the core body K. The core body K forms a magnetic path on the unit fixing part side. The core body K has a magnetic pole core 41 of an integral structure including a plurality of magnetic poles 411a, 412a and an inter-pole part 415, and a magnetic path core 42 that is magnetically coupled to the magnetic pole core 41 and integrally forms a magnetic path together with the magnetic pole core 41.

[0032] In this embodiment, the core body K has rod-shaped bodies 411 and 412 having multiple magnetic poles 411a and 412a, and an enclosing portion 420 that is arranged to surround the rod-shaped bodies 411 and 412 on all four sides and forms a magnetic path connecting the magnetic poles 411a and 412a. By combining a magnetic pole core 41 and a magnetic path core 42, the core body K surrounds rectangular parallelepiped rod-shaped bodies 411 and 412 having a cross-sectional area longer in the axial direction (thickness direction) than the width of the magnetic path with rectangular parallelepiped sides that are longer in the axial direction (thickness direction) than the width of the magnetic path.

[0033] The magnetic pole core 41 and the magnetic path core 42 allow the magnetic flux generated when current is passed through the coils 44, 45 to pass through the multiple magnetic poles 411a, 412a. The magnetic pole core 41 and the magnetic path core 42 are laminated cores formed by laminating electromagnetic steel sheets (laminated members) such as silicon steel sheets. By making the magnetic pole core 41 and the magnetic path core 42 have a laminated structure, they can be formed into complex shapes at low cost.

[0034] <Magnetic pole core 41> The magnetic pole core 41 has an integral structure including a plurality of rod-shaped bodies 411, 412 each having a plurality of magnetic poles 411a, 412a at their tip, and a connecting frame-shaped body 413 that connects the plurality of magnetic poles 411a, 412a and is provided with an interpole portion (an example of a second magnetic attraction member) 415.

[0035] The rod-shaped bodies 411 and 412 extend parallel to each other from base ends 411b and 412b to tip ends (including magnetic poles 411a and 412a), and a plurality of coils 44 and 45 are respectively attached to the exterior of the intermediate portions.

[0036] When the coils 44, 45 are energized and magnetized, the magnetic poles 411a, 412a at the tips of the rod-shaped bodies 411, 412 generate polarities according to the direction of energization.

[0037] The thickness of the rod-shaped bodies 411, 412 may be close to the thickness of the core body K itself (the length in the extension direction of the rotation shaft 24), and the bobbins 46, 47 are fitted around them. In the magnetic pole core 41, the rod-shaped bodies 411, 412 are flush with each other on one side in the thickness direction (the lower side in FIGS. 3 and 4, the upper side in FIGS. 6 to 8) relative to the connecting frame body 413 (planes perpendicular to the axial direction). On the other hand, between the other side (the upper side in FIGS. 3 and 4, the lower side in FIGS. 6 to 8) of the rod-shaped bodies 411, 412 and the connecting frame body 413, the rod-shaped bodies 411, 412 and the inter-pole section 415 are arranged in positions that protrude in the thickness direction (axial direction) beyond the connecting frame body 413.

[0038] In this way, a step portion is provided on the other surface of the magnetic pole core 41 by the rod-shaped bodies 411, 412 and the connecting frame-shaped body 413, and this step portion engages with a step portion on the magnetic path core 42 side. As a result, the rod-shaped bodies 411, 412 are configured to be on the same plane as the surrounding portion 420, with only the axial height differing.

[0039] The magnetic poles 411a, 412a are arranged to face the outer peripheral surface of the magnet 26 with a predetermined gap therebetween. The portions (magnetic poles) of the magnetic poles 411a, 412a that face the outer peripheral surface of the magnet 26 are formed into curved shapes that correspond to the shape of the outer peripheral surface and follow the outer peripheral surface of the magnet 26. These curved portions are arranged to face each other with a predetermined gap (air gap) G (see FIG. 5) therebetween in a direction perpendicular to the extension direction of the rod-shaped bodies 411, 412, for example.

[0040] 5 to 8, the magnetic poles 411a, 412a have external dimensions that allow bobbins 46, 47 around which coils 44, 45 are wound to be fitted from the tip side. As a result, the bobbins 46, 47 can be positioned so as to surround the tip side in the extension direction of the rod-shaped bodies 411, 412, that is, the region from the tip of the magnetic poles 411a, 412a to the base end portions 411b, 412b side to the central portion of the rod-shaped bodies 411, 412.

[0041] The connecting frame 413 is U-shaped and connects the rod-shaped bodies 411, 412 to each other, joining the multiple magnetic poles 411a, 412a together. In addition, the connecting frame 413 has an inter-pole portion 415 arranged between the rod-shaped bodies 411, 412 in parallel with the rod-shaped bodies 411, 412. When the magnetic pole core 41 is assembled to the magnetic path core 42, the connecting frame 413 abuts against the surrounding portion 420 of the magnetic path core 42 and, together with the surrounding portion 420, forms a magnetic path that surrounds the magnetic poles 411a, 412a.

[0042] The connection frame-shaped body 413 has a rectangular parallelepiped connection side portion 4131 and protruding side portions 4132 and 4133 extending from both ends of the connection side portion 4131 in a direction perpendicular to the connection side portion 4131 .

[0043] The connecting side 4131 is arranged to extend in a direction perpendicular to the parallel direction of the rod-shaped bodies 411, 412 and the inter-pole portion 415, and is joined perpendicularly to the respective base ends 411b, 412b, 415b. The inter-pole portion 415 is joined to the center of the connecting side 4131, and the rod-shaped bodies 411, 412 extend parallel to the inter-pole portion 415 and are joined integrally to the connecting side 4131 so as to sandwich the inter-pole portion 415. In the connecting side 4131, the rod-shaped bodies 411, 412 and the inter-pole portion 415 are arranged between and parallel to the protruding sides 4132, 4133 that are joined perpendicularly to both end portions.

[0044] The connecting side portion 4131 is positioned and joined to overlap with the frame bottom side portion 423 of the magnetic path core 42 in the thickness direction (extension direction of the rotation shaft 24). The protruding side portions 4132, 4133 are positioned and joined to overlap with the frame side side portions 421, 422 of the magnetic path core 42, respectively, in the thickness direction. Mounting holes 401 are provided at the corners formed by the connecting side portion 4131 and the protruding side portion 4132, and the connecting side portion 4131 and the protruding side portion 4132. These corners are also two of the four corners of the core body K when viewed from above, and fastening materials 32 are inserted into the mounting holes 401 to fix the first shaft support 50, the magnetic path core 42, and the second shaft support 60.

[0045] The protruding sides 4132, 4133, together with the connecting side 4131, form, for example, a U-shaped connecting frame body 413, which is the surface on the magnetic path core 42 side and has a planar magnetic pole side contact surface 4130 that comes into surface contact with the magnetic path side contact surface 4201 of the magnetic path core 42. The connecting frame body 413 may have a shape obtained by cutting out a portion of a polygonal frame body or a circular frame body, such as a substantially U-shape or C-shape.

[0046] The magnetic pole side contact surface 4130 is provided over the entire area of ​​the U-shaped connecting frame 413 that faces the magnetic path core 42. The connecting frame 413 is joined in a stacked state to the frame bottom portion 423, with the magnetic pole side contact surface 4130 in full surface contact with the magnetic path side contact surface 4201 of the magnetic path core 42.

[0047] Furthermore, the connecting side portion 4131 is provided with a positioning hole 403 penetrating in the thickness direction for positioning each part when joining the magnetic path core 42, the first shaft support 50, and the second shaft support 60 together. The positioning hole 403 communicates with the positioning hole 404 of the magnetic path core 42.

[0048] 2 to 8, the inter-pole section 415 is made of a magnetic material and is disposed opposite the magnet 26 at a predetermined distance in a direction perpendicular to the axial direction. The inter-pole section 415 is disposed, for example, so as to surround the magnet 26 on all four sides together with the magnetic poles 411a, 412a and the rotation angle position holder 48. The inter-pole section 415 generates a magnetic attraction force (second magnetic attraction force) between itself and the magnet 26, thereby moving the magnet 26 to the rotation reference position.

[0049] The inter-pole section 415 generates a magnetic attractive force between itself and the magnet 26 (more specifically, the pole 262), and moves the pole 262 of the magnet 26, which is different from the pole 261 that is attracted to the rotation angle position holder 48, to a position where they face each other. Through this action, the inter-pole section 415 cancels out the axial radial load acting on the unit movable section 20 due to the magnetic attractive force (first magnetic attractive force) in the rotation angle position holder 48. Note that "canceling the axial radial load" also includes "making it possible to cancel out the axial radial load."

[0050] Specifically, inter-pole section 415 is provided integrally with magnetic pole core 41, and has inter-pole surface 4150 that faces magnet 26. Inter-pole surface 4150 preferably has a shape that corresponds to the outer peripheral surface of magnet 26. Inter-pole surface 4150 is preferably disposed so as to face the outer peripheral surface of magnet 26 over a wide area, with an equal distance (for example, G) between them. It is particularly preferable that inter-pole surface 4150 be formed to have the same area and shape as the surface of magnet 26 that faces rotation angle position holder 48.

[0051] That is, the inter-pole unit 415 positions the magnet 26, which is arranged to be rotatable back and forth between the magnetic poles 411a and 412a, at a rotation reference position, which is a reference position where the distance is the same when the magnet 26 rotates back and forth. The inter-pole unit 415, together with the magnetic pole face 49 of the rotation angle position holder 48, attracts one of the magnetic poles of the magnet 26, and positions the magnetic pole switching units 263 and 264, which are the boundary between the different poles on the outer periphery of the magnet 26, in a position facing the magnetic poles 411a and 412a.

[0052] The interpole portion 415 is provided so as to extend from the connecting side portion 4131 in parallel with the rod-shaped bodies 411 and 412 . The interpole portion 415 has a thickness length that is the same as the length of the rods 411 and 412, that is, the length of the magnetic poles 411a and 412a, and is longer than the axial length of the magnet . Additionally, the interpole portion 415 is disposed between the rod-shaped bodies 411 and 412, and the interpole surface 4150 is formed in the shape of a circular arc curved in the circumferential direction between the magnetic poles 411a and 412a.

[0053] In this embodiment, the interpole section 415 has two magnetic poles 411a, 412a and the magnet 26 also has two poles, so the interpole surface 4150, which serves as a magnetic pole, is positioned opposite the magnetic pole surface 49 of the rotation angle position holding section 48. The interpole portion 415 has a gap between the rod-shaped bodies 411 and 412, at which the peripheral walls of the bobbins 46 and 47 are disposed.

[0054] Because the inter-pole portion 415 is provided integrally with the magnetic path core 42, the inter-pole portion 415 can be formed to be strong and with high positional accuracy together with the magnetic poles 411a, 412a. This provides durability against the load caused by the magnetic attractive force generated between the inter-pole portion 415 and the magnet 26. Furthermore, the inter-pole portion 415, which is integral with the magnetic pole core 41, is arranged with high positional accuracy and generates a suitable magnetic attractive force with little variation, which can offset the axial radial load on the unit movable portion 20 caused by the magnetic attractive force of the rotation angle position holder 48.

[0055] Furthermore, the inter-pole section 415, together with the rotation angle position holding section 48, is arranged within the core body K so as to surround the magnet 26, resulting in a layout that occupies the smallest possible space, enabling the realization of a more compact rotary reciprocating drive actuator 1.

[0056] In the magnetic pole core 41, the rod-shaped bodies 411, 412, the connecting frame-shaped body 413, and the inter-pole portion 415 have an integrated structure. This means that when assembling the rotary reciprocating drive actuator 1, the positional relationship between the multiple magnetic poles 411a, 412a and the positional relationship between the inter-pole portion 415 and the magnetic poles 411a, 412a do not change.

[0057] That is, the magnetic pole core 41, together with the magnetic path core 42, is arranged as the core body of the core assembly 40, with the magnetic poles 411a and 412a positioned to face the magnet 26, and is arranged as the unit fixing part 30. With this configuration, the magnetic poles 411a and 412a can be positioned accurately facing each other without any misalignment.

[0058] <Magnetic path core 42> The magnetic path core 42 is joined to the magnetic pole core 41, and forms a magnetic path through which magnetic flux passes to the magnetic poles 411a and 412a when current is applied to the coils 44 and 45. When current is not applied, the magnetic path core 42, together with the magnetic pole core 41 and the magnet 26, forms a magnetic path through which magnetic flux passes to the rotation angle position holding portion 48 and the interpole portion 415.

[0059] The magnetic path core 42 faces the connecting frame 413 of the magnetic pole core 41 in the extension direction of the rotating shaft 24, and they are in surface contact with each other, and is assembled with the magnetic pole core 41 in a state where the multiple magnetic poles 411a, 412a are positioned around the rotating shaft 24.

[0060] In addition to the surrounding portion 420 , the magnetic path core 42 has a magnetic path side contact surface 4201 , a notch portion 4202 , an engaging recess 402 , and a positioning hole 404 .

[0061] The magnetic path core 42 surrounds the coils 44 and 45 with a surrounding portion 420, and a connection frame-shaped body 413 of the magnetic pole core 41 is engaged and connected at a cutout portion 4202 in part of the surrounding portion 420. The surrounding portion 420 is disposed so as to surround the coils 44 and 45 as well as the magnetic poles 411 a and 412 a and the rotation shaft 24 .

[0062] The surrounding portion 420 is formed, for example, in the shape of a rectangular frame and has high strength. When the connecting frame-shaped body 413 engages with the surrounding portion 420, the magnetic path core 42 comes into surface contact with the magnetic path-side contact surface 4201 and the magnetic pole-side contact surface 4130 of the magnetic path core 42, and is tightly attached to the magnetic pole core 41, forming an integrated rectangular frame-shaped body as the core body K, all of which have the same thickness (axial length).

[0063] Specifically, the surrounding portion 420 is formed by joining together a frame bottom portion 423, both frame side portions 421, 422, and a bridge portion 427 into a rectangular frame shape. In the surrounding portion 420, the cutout portions 4202 are formed by cutting out a portion of the surface facing the magnetic pole core 41 in each of the frame bottom portion 423 and both frame side portions 421, 422.

[0064] The magnetic path-side contact surface 4201 has a shape corresponding to the connecting frame 413, for example, a U-shape, and is provided on the bottom surface of the cutout portion 4202, i.e., on part of the surfaces of the frame bottom portion 423 and both frame side portions 421, 422 facing the magnetic pole core 41. The magnetic path-side contact surface 4201 comes into surface contact with the magnetic pole-side contact surface 4130 of the connecting frame 413 so as to completely overlap, thereby reducing magnetic resistance at the joint between the enclosure portion 420 and the connecting frame 413. Note that the magnetic path-side contact surface 4201 may have any shape as long as it corresponds to the connecting frame 413, and the magnetic path-side contact surface 4201 may have a shape obtained by cutting out a part of a polygonal frame or a circular frame, such as a substantially U-shape or C-shape corresponding to the connecting frame 413.

[0065] The frame side edges 421, 422 are joined to the protruding edges 4132, 4133 so as to overlap in the axial direction. The frame side edges 421, 422 are arranged to sandwich the pair of rod-shaped bodies 411, 412 and extend along the parallel direction of the pair of rod-shaped bodies 411, 412. The frame side edges 421, 422 are joined at their base ends 421b, 422b to both ends of the frame bottom edge 423. The frame side edges 421, 422 are an example of a pair of legs of the core body K. A bridge 427 parallel to the frame bottom edge 423 is installed between the tip ends of the frame side edges 421, 422.

[0066] When the frame bottom portion 423 is stacked so as to abut and overlap the connecting frame-shaped body 413, the base end faces of the multiple rod-shaped bodies 411, 412 protruding from the connecting frame-shaped body 413 side into the frame bottom portion 423 abut against the inner surface of the frame bottom portion 423. As a result, the frame bottom portion 423 and the connecting frame-shaped body 413 are joined to the rod-shaped bodies 411, 412 in surface contact, allowing magnetic flux to easily pass between them.

[0067] The engaging recesses 402 are provided at the four corners of the surrounding portion 420, i.e., at the bent portions of the corners of the rectangular frame-shaped magnetic path, so as to extend in the axial direction. The mounting legs 56 of the first shaft support 50 fit into the engaging recesses 402 (see FIGS. 2 to 5).

[0068] The bridge 427 constitutes the upper frame of the surrounding part 420, which forms a magnetic path connecting the magnetic poles 411 a and 412 a. The bridge 427 is installed between the tip ends of the frame side parts 421 and 422 in parallel to the frame bottom part 423, and also connects the tip ends of the protruding parts 4132 and 4133 of the magnetic pole core 41 in an installed state. The bridge 427 has attachment holes 401 at both ends thereof which communicate with the engagement recesses 402, and further has a positioning hole 405 which penetrates through in the axial direction.

[0069] <Rotation angle position holding unit (an example of a first magnetic attraction member) 48> Rotation angle position holder 48 is disposed so that magnetic pole surface 49 faces magnet 26 across air gap G. Magnetic pole surface 49 is formed in an arc shape corresponding to the outer peripheral surface of magnet 26. Rotation angle position holder 48 displaces magnet 26 around rotation axis 24 by a magnetic attractive force (first magnetic attractive force) generated between rotation angle position holder 48 and magnet 26 (more specifically, pole 261), attracting magnet 26 so that it is positioned at the rotation reference position.

[0070] The rotation reference position is the rotation center position when the magnet 26 rotates back and forth, and is a position where the magnet 26 can move and displace at the same angle when it moves in one direction around the axis and in the opposite direction when it rotates back and forth around the rotation axis 24.

[0071] The rotation angle position holder 48 may be a magnet or a magnetic material (particularly preferably a ferromagnetic material).

[0072] The rotation angle position holder 48 forms a magnetic spring by generating a magnetic attraction force between itself and one pole 261 of the magnet 26, and the one pole 261 of the magnet 26 is positioned opposite the rotation angle position holder 48.

[0073] Due to this magnetic spring, when coils 44, 45 are not energized (de-energized), rotational angle position holder 48 is attracted to the pole of magnet 26, which has a larger opposing area and closer distance than magnetic poles 411a, 412a, thereby holding magnet 26 at the rotation reference position. Note that due to the magnetic attractive force between rotational angle position holder 48 and pole 261, a load is generated in unit moving part 20 in the axial direction (first axial radial direction) from the center of rotating shaft 24 toward rotational angle position holder 48. As described above, in this embodiment, due to the magnetic attractive force between inter-pole part 415, which is located on the opposite side of rotational angle position holder 48 with respect to the center of rotating shaft 24, and pole 262, a load is also generated in unit moving part 20 in the axial direction (second axial radial direction) from the center of rotating shaft 24 toward inter-pole part 415. By making the loads in both directions equal and canceling each other out, it is possible to prevent undesirable loads from being applied to the parts that come into contact with the rotating shaft 24, such as the first bearing 54 and the second bearing 64.

[0074] In the core assembly 40, the rotation angle position holder 48 is composed of a magnet. In this configuration, for example, the rotation angle position holder 48 is arranged so that a pole 262, which is the same as the pole (one pole) 261 of the magnet 26 of the unit movable part 20 to be attracted, is opposite the magnet 26 when it is positioned at the rotation reference position, at a midpoint between the magnetic poles 411a and 412a. The rotation angle position holder 48 is arranged so that the poles directly opposite the pole of the magnet 26 in the rotation reference position are poles that attract each other, and it is desirable that the shapes of the poles correspond to each other. For example, if the poles 261 are S poles and the pole 262 are N poles (see FIGS. 13 and 14), then in the rotation angle position holder 48, the arc-shaped magnetic pole surface facing the pole 261 of the magnet 26 is the N pole.

[0075] The rotation angle position holder 48 is disposed in the unit fixing section 30, specifically, in the core assembly 40. The rotation angle position holder 48 is disposed between the bridge 427 and the magnet 26, and in this embodiment, the rotation angle position holder 48 is attached to the bridge 427 of the magnetic path core 42 (the portion above the rod-shaped bodies 411, 412 of the magnetic pole core 41) in an orientation in which the magnetic pole faces the magnet 26. Note that the rotation angle position holder 48 does not have to be a magnet, and may be made of a magnetic material that generates a magnetic attractive force between itself and the magnet 26.

[0076] The positioning holes 404, 405 are holes used to position each part (first shaft support 50, core assembly 40, and second shaft support 60) that constitutes the unit fixing part 30. As shown in Figures 3 and 4, the positioning hole 404 is formed with the same diameter and has the same axis as the positioning hole 403 of the magnetic pole core 41, the positioning hole 501 of the first shaft support 50, and the positioning hole 601 of the second shaft support 60. These positioning holes 403, 404, 501, and 601 form a positioning through hole that is continuous in the axial direction.

[0077] The positioning hole 405 is formed with the same diameter and has the same axis as the positioning hole 502 of the first shaft support 50 and the positioning hole 602 of the second shaft support 60, and forms a positioning through hole that is continuous in the axial direction. The positioning hole 405 of the magnetic path core 42, the positioning hole 502 of the first shaft support 50, and the positioning hole 602 of the second shaft support 60 are each, for example, an elongated hole that is formed by passing through the unit fixing portion 30 in the axial direction.

[0078] With this configuration, when joining the core assembly 40, the first shaft support 50, and the second shaft support 60, the positioning holes 403, 404, 501, and 601 are arranged so as to be continuous in the axial direction, and a positioning rod is inserted through them. In addition, the positioning holes 405, 502, and 602 are arranged so as to be continuous in the axial direction, and an elongated through-hole is formed, through which a positioning rod is inserted.

[0079] In this way, the core assembly 40 is sandwiched between the first shaft support 50 and the second shaft support 60, with each positioned accordingly. Next, the fastening member 32 is inserted and secured, for example, from the second shaft support 60 side, through the fastening hole 603 of the second shaft support 60, the mounting hole 401 of the core assembly 40, and the fastening hole 503 of the first shaft support 50 (for example, by tightening a screw serving as the fastening member 32). As a result, the first shaft support 50 and the second shaft support 60 are fixed to the core assembly 40 with the core assembly 40 sandwiched between them.

[0080] In this way, positioning holes 403, 404, 501, 601 and positioning holes 405, 502, 602 each function as a common positioning hole. Rods can be inserted into these common positioning through-holes, and each part can be positioned using this as a reference during assembly. Rotary reciprocating drive actuator 1 is then assembled, which improves assembly accuracy, prevents a decline in reciprocating rotation performance, and reduces variations in reciprocating rotation output.

[0081] When the rotary reciprocating drive actuator 1 is assembled, the rotary shaft 24 is inserted into the space surrounded by the magnetic poles 411a and 412a. The magnet 26 attached to the rotary shaft 24 is positioned in this space, and the magnetic poles 411a and 412a face the magnet 26 at a precise position across the air gap G.

[0082] The coils 44, 45 are wound around cylindrical bobbins 46, 47. A coil body consisting of the coils 44, 45 and the bobbins 46, 47 is extrapolated 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. In this way, the coils 44, 45 are arranged adjacent to the magnetic poles 411a, 412a at the tip ends of the rod-shaped bodies 411, 412.

[0083] The winding direction of the coils 44, 45 is set so that magnetic flux is suitably generated from one of the magnetic poles 411a, 412a of the magnetic pole core 41 to the other when current is applied.

[0084] <Variation 1> Figure 9 is a bottom side perspective view of modified example 1 of the core assembly, Figure 10 is a plan cross-sectional view showing the main configuration of modified example 1 of the core assembly, Figure 11 is a bottom side perspective view of the core body in modified example 1 of the core assembly, and Figure 12 is an exploded view of the same core body.

[0085] 9 to 12, core assembly 40A as modified example 1 differs from core assembly 40 in that rotation angle position retaining section 48 is made of a magnetic material and is integrated with magnetic path core 42A. Therefore, components that are the same as those in embodiment 1 are given the same names and symbols and their explanations are omitted, and components that are similar to those in embodiment 1 but have differences are appropriately given the letter "A" and will be appropriately explained.

[0086] The core assembly 40A is applied to the rotary reciprocating drive actuator 1, for example, in place of the core assembly 40. The core assembly 40A forms a magnetic circuit together with the magnet 26 (see FIGS. 3 to 5). The core assembly 40A has coils 44, 45, a core body K1 around which the coils 44, 45 are wound, and a rotation angle position holder 48A.

[0087] The core assembly 40A (specifically, the core body K1) has a magnetic pole core 41A configured similarly to the magnetic pole core 41, and a magnetic path core 42A that is combined with the magnetic pole core 41A to form the core body K1.

[0088] The magnetic pole core 41A integrally includes rod-shaped bodies 411 and 412 having a plurality of magnetic poles 411a and 412a, an interpole portion 415, and a connection frame-shaped body 413. The magnetic path core 42A has a rotation angle position retaining portion 48A, which is also a magnetic material, integral with a bridge portion 427A of an enclosure portion 420A, which is also a magnetic material, and is otherwise configured and functions in the same manner as the magnetic path core 42. The enclosure portion 420A includes a frame bottom portion 423A, both frame side portions 421, 422, and the bridge portion 427A.

[0089] In this way, by forming the rotation angle position holding unit 48A as a magnetic material and as part of the core body K1, specifically as part of the magnetic path core 42A, it is possible to reduce the number of steps and the cost of parts compared to when the rotation angle position holding unit 48A is configured as a separate body from the core body.

[0090] <Shaft Supports (First Shaft Support 50 and Second Shaft Support 60)> The first shaft support member 50 and the second shaft support member 60 shown in FIGS. 2 to 4 function as an electromagnetic shield, rotatably support the rotating shaft 24, and are fixed to the core assembly 40 by sandwiching the core assembly 40 therebetween.

[0091] The first shaft support 50 and the second shaft support 60 are disposed 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 into the core body K and the emission of noise from the core body K to the outside. The first shaft support 50 and the second shaft support 60 each have a positioning recess 15 on their side, which functions as a positioning mechanism when the rotary reciprocating drive actuator 1 itself is mounted on a product. This allows the rotary reciprocating drive actuator 1 to be positioned, for example, by engaging the positioning recess 15 with an engaging portion provided at the mounting location of the product.

[0092] The first shaft support 50 and the second shaft support 60 have support main body portions 52, 62 provided with through holes 521, 621, and bearings (first bearing 54, second bearing 64) that fit into the through holes 521, 621.

[0093] The support body portions 52, 62 are each made of a conductive material and cover the core assembly 40, specifically, the end faces of the core body K that are spaced apart in the axial direction. The support body portions 52, 62 of the first shaft support 50 and the second shaft support 60 are preferably formed from, for example, an aluminum alloy. Aluminum alloys offer a high degree of design freedom and can easily impart the desired rigidity. Therefore, they are suitable when the first shaft support 50 and the second shaft support 60 function as shaft supports that receive and support the rotating shaft 24.

[0094] <1st shaft support 50> 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 rotary shaft 24 .

[0095] The first bearing 54 of the first shaft support 50 is fitted into a through hole 521 of the support body 52, and the rotating shaft 24 is rotatably inserted through the first bearing 54. The first shaft support 50 supports the rotating shaft 24 via the first bearing 54 with one end of the rotating shaft protruding so that the rotating shaft 24 can rotate back and forth. A bearing mounting portion 5211 is formed on the back side (core assembly 40 side) of the through hole 521.

[0096] The first bearing 54 is fitted into the bearing attachment portion 5211 on the back surface from the core assembly 40 side (back surface side), whereby the flange portion of the first bearing 54 engages with the opening edge of the through hole 521, and the first bearing 54 is fitted into the through hole 521 in a state where movement in the fitting direction is restricted. The bearing attachment portion 5211 is formed, for example, in a recessed shape continuous with the through hole 521 on the back surface of the first shaft support 50, and the first bearing 54 is fitted into this recessed shape. The first bearing 54 is formed, for example, by a rolling bearing or a sliding bearing. The first shaft support 50 has positioning holes 501 and 502, a mounting leg portion 56, and a core holding portion 58 that protrudes from the support body portion 52 toward the inside of the core assembly 40.

[0097] The core holding portion 58 is interposed between the magnetic poles 411a, 412a and the frame side edges 421, 422 and the protruding edges 4132, 4133. The core holding portion 58 can prevent the magnetic poles 411a, 412a from moving relative to the frame side edges 421, 422 and the protruding edges 4132, 4133, and can hold them in their positions.

[0098] This makes it possible to suppress deformation of the core body K in the core assembly 40 due to impact or vibration. The core holding portions 58 may be interposed between the magnetic poles 411a, 412a and both side portions of the surrounding portion made up of the integrated frame side portions 421, 422 and the protruding side portions 4132, 4133.

[0099] The positioning holes 501 and 502 are formed in the support body 52 at the center of each of the opposing sides thereof, penetrating the support body 52 in the axial direction.

[0100] The mounting legs 56 are provided protruding from the four corners on the back side of the support body 52. ​​The mounting legs 56 are used to join the first shaft support 50, the second shaft support 60, and the core assembly 40 together.

[0101] The shape of the mounting legs 56 corresponds to, for example, the shape of the engaging recess 402 of the core body K. Each mounting leg 56 is formed with a fastening hole 503 penetrating therethrough in the axial direction.

[0102] The mounting legs 56 are arranged on the four corner sides extending along the axial direction of the rotation shaft 24 of the unit fixing part 30, which has a rectangular columnar shape including a cube shape, a rectangular parallelepiped shape, or the like, for example, a cube shape, and engage with the engaging recesses 402 of the core assembly 40. In this engaged state, the first shaft support body 50 is fixed to the second shaft support body 60 by inserting the fastening members 32 inserted into the fastening holes 503 in the mounting legs 56 into the corresponding mounting holes 401 at the four corners of the core assembly 40 and fastening them to the second shaft support body 60.

[0103] As a result, the first shaft support body 50 restricts the core body K, and therefore the core assembly 40, to only move away from the first shaft support body 50 in the axial direction, and is fixed to the core assembly 40A and the second shaft support body 60 so as to also restrict movement in the axial direction by the fastening material 32. In other words, the first shaft support body 50 and the core assembly 40 are restricted from moving relative to each other in a direction intersecting the axial direction of the rotation shaft 24, and are securely attached together.

[0104] <Second shaft support 60> 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 rotary shaft 24 .

[0105] The second bearing 64 of the second shaft support 60 is fitted into a through hole 621 of the support main body 62, and the rotary shaft 24 is rotatably inserted through the second bearing 64. The second shaft support 60 supports the rotary shaft 24 so that it can rotate back and forth via the second bearing 64, with the other end side of the rotary shaft 24 protruding. A bearing mounting portion 6211 is formed on the back side (core assembly 40 side) of the through hole 621.

[0106] The second bearing 64 is fitted into the bearing attachment portion 6211 from the core assembly 40 side, whereby a flange portion of the second bearing 64 engages with the opening edge of the through hole 621, and the second bearing 64 is fitted into the through hole 621 in a state where movement in the fitting direction is restricted. The bearing attachment portion 6211 is formed, for example, in a recessed shape continuous with the through hole 621 on the back surface of the second shaft support 60, and the second bearing 64 is fitted into this recessed shape. Note that the second bearing 64 is constituted, for example, by a rolling bearing, but may also be constituted by a bearing such as a plain bearing.

[0107] The second shaft support 60 constitutes the core assembly 40 together with the first shaft support 50 via the fastening material 32 and has a fastening hole 603 as a fastening portion used together with the fastening material 32 .

[0108] The fastening holes 603 are provided in the support body portion 62 at positions corresponding to the fastening holes 503 of the first shaft support 50 and the mounting holes 401 of the core assembly 40, i.e., at positions facing each other in the axial direction. The support body portion 62 is formed at each of the four corners, and the fastening members 32 are inserted therein to engage with parts of the fastening members 32, here, the flange portions of the heads. Note that, when the fastening members 32 are screws or the like, the support body portion 62 is provided with recesses for accommodating the screw heads (the heads of the fastening members 32), and the fastening holes 603 are disposed in the recesses. As a result, even when the shafts of the fastening members 32, such as bolts or screws, are inserted through the fastening holes 603 and the heads of the fastening members 32 are engaged around the fastening holes 603, the heads of the fastening members 32 are accommodating the recesses so that they do not protrude outward.

[0109] In this way, the first shaft support 50 and the second shaft support 60 sandwich the core assembly 40 having the core body K consisting of the magnetic pole core 41 and the magnetic path core 42 via the fastening material 32, and are fixed to the core assembly 40, thereby being integrated as the unit fixing part 30 of the drive unit 10.

[0110] <Moving unit part 20> The magnet 26 is a ring-shaped magnet in which poles 261 (hereinafter, also referred to as "South poles 261" for convenience) and poles 262 (hereinafter, also referred to as "North poles 262" for convenience) are arranged alternately in the circumferential direction. The magnet 26 is attached to the circumferential surface of the rotating shaft 24 so as to be located in the space surrounded by the magnetic poles 411a, 412a of the core body K when the rotary reciprocating drive actuator 1 is assembled. When current is applied to the coils 44, 45, the rod-shaped bodies 411, 412 and the magnetic path core 42 are excited, and polarities corresponding to the current application direction are generated in the magnetic poles 411a, 412a, and magnetic forces (attraction and repulsion) are generated between the magnetic poles 411a, 412a and the magnet 26.

[0111] In this embodiment, the magnet 26 is magnetized with different polarities with a plane along the axial direction of the rotating shaft 24 as the boundary. That is, the magnet 26 is a two-pole magnet that is magnetized so as to be equally divided into an S pole 261 and an N pole 262. The number of magnetic poles of the magnet 26 (two in this embodiment) is equal to the number of magnetic poles 411a, 412a of the core body K. Note that the magnet 26 may be magnetized with two or more poles depending on the amplitude during movement. In this case, the magnetic pole portions of the core body K are provided to correspond to the magnetic poles of the magnet 26.

[0112] As shown in Figures 2 to 4, the magnet 26 is arranged between the bearing 54 of the first shaft support 50 and the bearing 64 of the second shaft support 60, and between the annular spacer 25 and the preload spring 27.

[0113] A shaft support ring 28 is provided on the rotating shaft 24 so as to protrude radially from the other end portion thereof that passes through the second bearing 64 and protrudes outward from 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.

[0114] When the rotating shaft 24 is attached to the unit fixing part 30, the magnet 26 is arranged in the axial direction within the unit fixing part 30 on the other end side of the rotating shaft 24, with the spacer 25 interposed between the magnet 26 and the second bearing 64. On the other hand, on one end side of the rotating shaft 24, the magnet 26 is arranged between the first bearing 54 and the magnet 26 in a state where a preload is applied to the spacer side via the preload spring 27 sandwiched between the washers 27a, 27a.

[0115] In this way, the magnet 26 is positioned and disposed within the unit fixing part 30. In this state, when an external force is applied to the preload spring 27 in the direction in which the preload spring 27 is compressed, the shaft support ring 28 restricts movement of the rotating shaft 24 and the magnet 26 in the thrust direction (e.g., upward in FIG. 2) relative to the unit fixing part 30. Therefore, in particular, the components (encoder disk 74, etc.) of the angle sensor part 70 provided on the other end side of the rotating shaft 24 will not move together with the rotating shaft 24 and collide with other components, for example, the second bearing 64, and will not be damaged.

[0116] As shown in FIG. 5, the magnet 26 switches polarity at magnetic pole switching portions 263 and 264 which are boundaries between the south pole 261 and the north pole 262.

[0117] When the magnet 26 is held in the rotational reference position by the magnetic attraction force between it and the rotational angle position holding part 48, the outer ends of the magnetic pole switching parts 263 and 264 of the magnet 26 face directly opposite the magnetic poles 411a and 412a of the rod-shaped bodies 411 and 412.

[0118] At this time, the magnetic pole switching parts 263 and 264, which are the boundary parts, are arranged to extend in a direction perpendicular to the magnetic poles 411a and 412a. Also, the mounting posture of the mirror part 22 is adjusted based on the state in which the pole 261 of the magnet 26 is at the rotation reference position.

[0119] When magnet 26 is positioned at the rotation reference position, magnetic pole switching sections 263 and 264 of magnet 26 face magnetic poles 411a and 412a. When coils 44 and 45 are energized in this state, unit fixing section 30 generates maximum torque, enabling stable driving of the movable body.

[0120] Furthermore, by configuring magnet 26 as a two-pole magnet, cooperation with core body K makes it easier to drive the movable object to rotate back and forth with high amplitude, and improves drive performance. Note that, although the embodiment has been described with reference to a case where magnet 26 has a pair of magnetic pole switching units 263, 264, it may have two or more pairs of magnetic pole switching units. In this case, the configuration will have a corresponding number of magnetic poles 411a, 412a, and the rotation angle position holding unit 48 and inter-pole unit 415 will be disposed between magnetic poles 411a, 412a.

[0121] <Angle sensor part 70> The angle sensor unit 70 shown in FIGS. 1, 3 and 4 is attached to the outer surface side of the second shaft support 60, straddling the second shaft support 60 and the rotation shaft 24.

[0122] The angle sensor unit 70 has 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 inside the sensor mounting portion 78 by an adhesive 33. The sensor mounting portion 78 is case-shaped and also functions as a cover that covers the optical sensor 73. The sensor mounting portion 78 is fixed to the support main body portion 62 of the second shaft support 60 by an adhesive 34. The sensor mounting portion 78 covers the optical sensor 73. This prevents impurities such as dust from entering the optical sensor 73 and prevents optical interference, allowing for stable detection.

[0123] The encoder disk 74 has an annular shape and is fixedly attached to the other end of the rotating shaft 24 via a cylindrical portion on the inner periphery, and rotates integrally with the magnet 26 and the mirror portion 22. The encoder disk 74 is disposed so that the rotational position of the encoder disk 74 is the same as the rotational position of the rotating shaft 24, and 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. This allows the optical sensor 73 to detect the rotational positions of the magnet 26 and the mirror portion 22.

[0124] The angle sensor unit 70 is capable of detecting the rotation angle of the movable body including the magnet 26 and the rotation axis 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.

[0125] The optical sensor 73 of the angle sensor unit 70 is attached to a sensor mounting portion 78 that is attached to the second axis support 60. The optical sensor 73 can be easily removed by simply removing the sensor mounting portion 78 from the second axis support 60. A circuit board 79 for the drive power supply for the rotary reciprocating drive actuator 1 is attached to the sensor mounting portion 78. Coils 44, 45 are connected to this circuit board 79, which supplies power to the coils 44, 45.

[0126] This allows the angle sensor unit 70 to be easily replaced if a malfunction occurs. Also, the angle sensor unit 70 can be assembled in the final stage of assembly. As a result, the expensive angle sensor unit 70 can be assembled after confirming that the assembly of other parts is correct, which reduces the risk of wasting the expensive angle sensor unit 70, especially the optical sensor 73, due to improper assembly of other parts. Furthermore, even if a malfunction occurs in the actuator after installation, the optical sensor 73 can be quickly removed by removing the sensor mounting portion 78.

[0127] At the end of the rotating shaft 24 opposite to the end connected to the mirror unit 22, a stopper unit 75 is provided, which protrudes from the sensor mounting unit 78 and restricts the rotation of the rotating shaft 24. The stopper unit 75 is provided with a protrusion 76 that protrudes in the radial direction. As shown in FIG. 4, a restricting unit 77 is provided on the outer surface of the sensor mounting unit 78 within the rotation range of the protrusion 76.

[0128] When stopper portion 75 rotates, protrusion 76 swings and comes into contact with restriction portion 77, thereby restricting the rotation range. This limits the maximum rotation angle of rotating shaft 24 and prevents interference with other components, thereby preventing deformation and damage due to interference.

[0129] <Operation of rotary reciprocating drive actuator 1> Next, the operation of the rotary reciprocating drive actuator 1 will be described with reference to Fig. 5 and Fig. 13 to Fig. 16. Fig. 13 is a diagram illustrating the magnetic circuit of the rotary reciprocating drive actuator of the first embodiment when it is not energized, and Fig. 14 is a diagram illustrating the magnetic attraction force of the rotary reciprocating drive actuator of the first embodiment. Also, Fig. 15 and Fig. 16 are diagrams illustrating the magnetic circuit of the rotary reciprocating drive actuator of the first embodiment when it is energized.

[0130] The two magnetic poles 411a, 412a of the core body K of the core assembly 40 are arranged to sandwich the magnet 26 with an air gap G therebetween. When the coils 44, 45 are not energized, the magnet 26 is held in the rotation reference position by a magnetic attraction force (first magnetic attraction force) KF generated between the magnet 26 and the rotation angle position holding portion 48, and a magnetic attraction force (second magnetic attraction force) HF generated between the magnet 26 and the inter-pole portion 415, as shown in FIG.

[0131] Specifically, one of the south pole 261 and north pole 262 of magnet 26 (south pole 261 in FIG. 13) is attracted to the north pole of rotation angle position holder 48, and magnet 26 is positioned at the rotation reference position. The magnetic attraction force KF between rotation angle position holder 48 and magnet 26 generates a torque (also referred to as a "holding torque") that positions magnet 26 at the rotation reference position, that is, that rotates magnet 26 so as to position pole 261 at the rotation reference position. This holding torque applies a load (axial radial load) to the rotating shaft 24 toward the rotation angle position holding unit 48 via the magnet 26. In particular, as the holding torque increases, the load in the axial radial direction increases. This presses against the bearings 54, 64 (first bearing 54, second bearing 64) that support the rotating shaft 24, increasing the frictional force with the bearings (first bearing 54, second bearing 64), increasing torque loss, and may prevent the desired drive.

[0132] In this embodiment, since the inter-pole portion 415 is provided, the inter-pole portion 415 is attracted to the pole 262 by the magnetic attractive force HF between the inter-pole portion 415 and the other pole of the magnet 26 (the north pole 262 in FIG. 13). As a result, a holding torque due to the magnetic attractive force HF, similar to the magnetic attractive force KF, is generated in the magnet 26, causing the magnet 26 to rotate in the circumferential direction and displacing the other pole 262 of the magnet 26 to a position facing the inter-pole portion 415. At this time, the magnetic attractive force HF acts in the same direction as the magnetic attractive force KF in the circumferential direction and acts in the opposite direction to the magnetic attractive force KF in the radial direction.

[0133] The magnetic attractive force HF displaces the rotating shaft 24 in the radial direction of the rotating shaft 24 in the direction opposite to the rotation angle position holder 48 side via the magnet 26. This cancels out the load on the rotating shaft 24 in the radial direction of the shaft toward the rotation angle position holder 48 side due to the magnetic attractive force KF.

[0134] That is, as shown in Figures 13 and 14, the magnetic attraction force HF between the interpole portion 415 and the magnet 26 acts in the same circumferential direction as the magnetic attraction force KF between the rotation angle position holder 48 and the magnet 26, increasing the rotational force of the magnet 26 toward the rotation reference position.

[0135] The magnetic attractive force HF generates torque that moves the magnet 26 to the rotation reference position, just as if adding a magnetic spring due to the magnetic attractive force KF. Furthermore, as shown in FIG. 13, the magnetic attractive force HF applies a load to the rotating shaft 24 in the opposite direction to the load applied to the rotating shaft 24 in the radial direction by the magnetic attractive force KF. This applies a load in a direction that cancels out the load that causes a loss of rotational force in the rotating shaft 24, thereby canceling out the load applied to the rotating shaft 24 in the radial direction by the magnetic attractive force KF. The magnetic attractive force KF suppresses torque loss in the bearings (first bearing 54, second bearing 64), enabling increased controllability as a rotary reciprocating drive actuator.

[0136] As a result, the magnet 26 is positioned at the rotation reference position, and when not energized, the magnetic flux flows as shown in Fig. 14. At this time, the outer peripheral ends of the magnetic pole switching units 263 and 264 of the magnet 26 are positioned opposite the centers of the magnetic poles 411a and 412a of the core body K.

[0137] When current is applied to the coils 44 and 45, the core body K is excited, and the magnetic poles 411a and 412a have polarities corresponding to the direction of current application. As shown in FIG. 15 , when current is applied to the coils 44 and 45, a magnetic flux is generated inside the core body K, and the magnetic pole 411a becomes a north pole and the magnetic pole 412a becomes a south pole. As a result, the magnetic pole 412a magnetized to the south pole attracts the north pole 262 of the magnet 26, and the magnetic pole 411a magnetized to the north pole attracts the south pole 261 of the magnet 26. Then, a torque in the F direction is generated in the magnet 26 around the axis of the rotation shaft 24, and the magnet 26 rotates in the F direction. Accordingly, 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.

[0138] 16, when current is applied to coils 44 and 45 in the opposite direction, the flow of magnetic flux generated inside core body K reverses, and magnetic pole 411a becomes a south pole and magnetic pole 412a becomes a north pole. Magnetic pole 412a magnetized to a north pole attracts south pole 261 of magnet 26, and magnetic pole 411a magnetized to a south pole attracts north pole 262 of magnet 26. Then, torque -F in the opposite direction to the F direction is generated in magnet 26 around the axis of rotation shaft 24, and magnet 26 rotates in the -F direction. Accordingly, rotation shaft 24 also rotates, and mirror section 22 fixed to rotation shaft 24 also rotates. The rotary reciprocating actuator 1 rotates and reciprocates the mirror section 22 by repeating the above operations. 15 and 16, in the rotary reciprocating drive actuator 1, an inter-pole portion 415 is connected to a connecting frame-shaped body 413 and a frame bottom portion 423 of a core body K to connect between rod-shaped bodies 411 and 412 having magnetic poles 411a and 412a. Therefore, when current is applied to the coils 44 and 45, a magnetic flux that rotates the magnet 26 flows in the connection portion of the core body K with the inter-pole portion 415, thereby increasing the drive torque that rotates the magnet 26 in the circumferential direction.

[0139] In practice, the rotary reciprocating actuator 1 is driven by AC waves input to the coils 44, 45 from a power supply unit (e.g., corresponding to the drive signal supply unit 103 in FIG. 23). That is, the current flow direction of the coils 44, 45 is periodically switched. When the current flow direction is switched, a resultant force of the magnetic attractive force KF between the rotation angle position holder 48 and the magnet 26 and the magnetic attractive force HF between the interpole unit 415 and the magnet 26, i.e., the restoring force of the magnetic spring (magnetic spring torques FM and -FM shown in FIGS. 15 and 16 ), is generated. This causes the magnet 26 to return to the rotation reference position; more specifically, the south pole 261 of the magnet 26 is urged back to a position directly facing the magnetic surface of the rotation angle position holder 48. This causes a torque in the F direction and a torque in the opposite direction (-F direction) to act alternately on the movable body around the axis. This causes the movable body to rotate reciprocally.

[0140] The following briefly describes 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 (movable body) is J [kg m 2 ], the spring constant of the magnetic spring (magnetic poles 411a, 412a, interpole portion 415, rotation angle position holding portion 48, and magnet 26) in the direction around the axis is K sp [N·m / rad], the movable body has a resonance frequency F r It vibrates (reciprocating rotation) at [Hz].

[0141]

number

[0142] Since the movable body constitutes the mass part in the vibration model of the spring-mass system, the resonance frequency F of the movable body is applied to the coils 44 and 45. r When an AC wave having a frequency equal to the resonant frequency F of the movable body is input, the movable body is put into a resonant state. r By inputting an AC wave having a frequency substantially equal to the frequency of the movable body, the movable body can be vibrated efficiently.

[0143] Below are equations of motion and circuit equations that show the driving principle of the rotary reciprocating drive actuator 1. The rotary reciprocating drive actuator 1 is driven based on the equation of motion shown in equation (2) and the circuit equation shown in equation (3).

[0144]

number

[0145]

number

[0146] That is, the moment of inertia of the movable body in the rotary reciprocating drive actuator 1, 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 equation (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 a range that satisfies formula (3).

[0147] In this way, the rotary reciprocating actuator 1 is configured with the moment of inertia J of the movable body and the spring constant K of the magnetic spring. sp The resonant frequency F is determined by r When the coil is energized with an AC wave corresponding to the above, a large vibration output can be obtained efficiently.

[0148] The rotary reciprocating drive actuator 1 of this embodiment has a unit movable part (movable body) 20 and a unit fixed part (fixed body) 30. The unit movable part 20 has a magnet 26 fixed to a rotation shaft 24 (shaft part) to which a mirror part 22, which serves as a movable object, is connected, and is arranged so as to be rotatable back and forth around the rotation shaft 24.

[0149] The unit fixing portion 30 includes a plurality of magnetic poles 411a, 412a having a plurality of coils 44, 45, a rotation angle position holding portion (an example of a first magnetic attraction member) 48, and an interpole portion (a second magnetic attraction member) 415, which are arranged facing each other on the outer periphery of the magnet 26.

[0150] The rotation angle position holder 48 generates a magnetic attractive force (first magnetic attractive force) KF between itself and the magnet 26, which determines the rotation center position of the reciprocating rotation of the unit moving part 20. The inter-pole part 415 generates a magnetic attractive force (second magnetic attractive force) HF between itself and the magnet 26, which offsets the axial radial load acting on the unit moving part 20 by the magnetic attractive force KF. The rotary reciprocating drive actuator 1 generates a magnetic flux that passes through the multiple magnetic poles 411a, 412a by energizing the multiple coils 44, 45. As a result, the rotary reciprocating drive actuator 1 rotates the unit moving part 20 reciprocally around the axis of the rotation shaft 24 based on the rotation center position due to electromagnetic interaction between the magnetic flux and the magnet 26.

[0151] Furthermore, according to the first embodiment, a pair of shaft supports, that is, a first shaft support 50 and a second shaft support 60, which rotatably support the rotating shaft 24, are provided on both sides of the core assembly 40 in the direction in which the rotating shaft 24 extends. The pair of shaft supports 50, 60 are fixed to sandwich the core assembly 40, and support the reciprocating rotation of the unit movable part 20 about the axis of the rotating shaft 24 by electromagnetic interaction between the magnetic flux and the magnet 26.

[0152] In this embodiment, the mirror section 22, which is the movable object, is rotatably supported by both of a pair of shaft supports (50, 60) fixed to sandwich the core assembly 40, and is supported so as to be rotatable back and forth via the rotation shaft 24 protruding on one side from the unit fixing section 30. As a result, in the rotary reciprocating drive actuator 1, the mirror section 22 can be reliably supported so as to be stable and movable via the rotation shaft 24, even in a cantilevered configuration.

[0153] That is, in the unit fixing portion 30, the portion of the rotating shaft 24 where the magnet 26 is arranged is supported at two points by the first shaft support 50 and the second shaft support 60, sandwiching the core assembly 40. This ensures the linearity of the rotating shaft 24 even if the magnetic attraction force between the magnet 26 and the rotation angle position retaining portion 48 increases.

[0154] For example, suppose that the portion of the rotating shaft 24 where the magnet 26 is located is supported in a cantilevered state only by the second shaft support 60. In this case, if the magnetic attraction force between the magnet 26 and the rotation angle position holder 48 becomes large, there is a risk that the rotating shaft 24 will bend toward the rotation angle position holder 48, reducing its linearity, but this problem does not occur in this embodiment.

[0155] In this way, the rotary reciprocating drive actuator 1 can be made smaller and more space-saving, has impact resistance and vibration resistance properties, and can drive a movable object via the shaft in a more stable state with high amplitude.

[0156] Furthermore, since the coils 44, 45 are separated from the mirror section 22 via the rotation axis 24, there is no effect from heat generated by the coils, and compared to a configuration in which the mirror section is close to the coils, the input current can be made larger, enabling high-output (high-amplitude) reciprocating rotation drive to be achieved. Furthermore, since no coil is provided on the movable body side and the magnetic poles 411a, 412a and the inter-pole section 415 are integrated as the magnetic pole core 41, manufacturability is high and assembly precision can be maintained.

[0157] Furthermore, even if the moving part, for example, mirror part 22, is enlarged, the magnetic poles on the core side can be used as two magnetic poles, allowing for high amplitude reciprocating rotation. Furthermore, the load in the axial direction due to magnetic attractive force KF between rotation angle position holder 48 and magnet 26 is offset (canceled) by magnetic attractive force HF between interpole part 415 and magnet 26.

[0158] As a result, regardless of whether the rotating shaft 24 is de-energized or energized during reciprocating rotational drive, the load in the radial direction of the shaft that occurs when torque is applied to rotate the magnet 26 to the rotation reference position is reduced, and no load is applied in the radial direction of the shaft to the first bearing 54 or the second bearing 64. Because no load is applied in the radial direction of the shaft to the first bearing 54 or the second bearing 64, friction is less likely to occur when the rotating shaft 24 rotates, reducing torque loss in the first bearing 54 and the second bearing 64, allowing the rotating shaft 24 to rotate smoothly and drive efficiently to achieve high output. In addition, the biasing force by the magnetic spring between the rotation angle position holder 48 and the magnet 26 can be increased.

[0159] Furthermore, in the rotary reciprocating drive actuator 1 that rotates in a reciprocating manner, the load acting in the axial direction on the rotating shaft 24 as a magnetic spring or holding torque can be suppressed, ensuring an appropriate magnetic spring and holding torque without interfering with the reciprocating rotational drive of the rotating shaft 24.

[0160] Since the magnetic pole core 41 and the magnetic path core 42 are laminated members, they can be manufactured easily and at low cost, and can have complex shapes. The magnetic pole core 41 has an integral structure of a plurality of rod-shaped bodies 411, 412 and a connecting frame-shaped body 413 that connects the rod-shaped bodies 411, 412 to each other. The rod-shaped bodies 411, 412 each have a plurality of magnetic poles 411a, 412a at their tip ends, extend parallel to each other from their base ends 411b, 412b to their tip ends, and are respectively fitted with a plurality of coils 44, 45 at their intermediate portions. The connecting frame-shaped body 413 extends at the base ends 411b, 412b in a direction that intersects with the parallel direction of the rod-shaped bodies 411, 412.

[0161] The magnetic path core 42 faces the connecting frame-shaped body 413 in the extension direction of the rotating shaft 24, and they are in surface contact with each other, and the magnetic pole core 41 is assembled by positioning the multiple magnetic poles 411a, 412a in a stable state with the coils 44, 45 adjacent to each other around the rotating shaft 24.

[0162] As a result, even with a core having magnetic poles 411a, 412a arranged to face each other across magnet 26, high output can be achieved, manufacturing costs can be reduced, and the magnetic poles 411a, 412a can be arranged with increased precision and consistency, thereby improving the reliability of rotary reciprocating drive actuator 1.

[0163] Furthermore, magnetic path core 42 has extensions (frame side portions 421, 422, bridge portion 427) that extend outward from rod-shaped bodies 411, 412, and these extensions form surrounding portion 420, which, together with connecting frame-shaped body 413, is disposed around rotation shaft 24 so as to surround coils 44, 45. This makes it possible to suppress electromagnetic noise generated from energized coils 44, 45, and further to suppress leakage magnetic flux from coils 44, 45 and magnet 26, thereby preventing electromagnetic effects on external devices.

[0164] Furthermore, if the rotation angle position holding unit 48 is a magnet, it can be positioned more accurately at a reference position, which is the rotation center position of the movable body when driving the movable body in a reciprocating rotational motion, and can be driven reciprocatingly from that position, thereby ensuring reliable reciprocating motion.

[0165] The movable object is mirror section 22 (particularly mirror 221) that reflects the scanning light. This allows rotary reciprocating drive actuator 1 to be used as a scanner that performs optical scanning. In this way, rotary reciprocating drive actuator 1 does not require multiple magnets on the movable section side, and even with a simple configuration using a single magnet, the magnet can be positioned at the center of reciprocating rotation, allowing the movable section to be driven more stably and with high amplitude.

[0166] (Embodiment 2) FIG. 17 is an external perspective view of the rotary reciprocating drive actuator 1B of embodiment 2, FIG. 18 is an exploded perspective view of the top side of the rotary reciprocating drive actuator 1B, and FIG. 19 is an exploded perspective view of the bottom side of the rotary reciprocating drive actuator 1B.

[0167] The rotary reciprocating drive actuator 1B is used in, for example, a LiDAR (Laser Imaging Detection and Ranging) device, similar to the first embodiment. Of course, the rotary reciprocating drive actuator 1B can also be applied to optical scanning devices such as multifunction peripherals and laser beam printers.

[0168] The rotary reciprocating drive actuator 1B can be broadly divided into a mirror portion 22B, a base portion 80B that rotatably supports the mirror portion 22B, and a drive unit 10B that drives the mirror portion 22B to rotate back and forth relative to the base portion 80B. As with the rotary reciprocating drive actuator 1, the rotary reciprocating drive actuator 1B may further be provided with an angle sensor similar to the angle sensor portion 70 that detects the rotational angle position of the mirror portion 22.

[0169] The rotary reciprocating actuator 1B has a core body K2 configured similarly to the rotary reciprocating actuator 1, and is driven by a magnetic circuit configured similarly to the magnetic circuit of the rotary reciprocating actuator 1.

[0170] <Mirror part 22B> The mirror section 22B is a movable object in the rotary reciprocating actuator 1B, and is connected to a rotation shaft 24B. The mirror section 22B is formed, for example, by attaching a mirror 221B to one surface of a mirror holder 222B. The rotation shaft 24B is inserted into an insertion hole in the mirror holder 222B and fixed thereto.

[0171] <Base part 80B> The base portion 80B has the rotary reciprocating actuator 1 fixed thereto and supports the mirror portion 22B so that it can reciprocate and rotate freely. The base portion 80B has a base main body 81B and bearings 82B and 83B.

[0172] The base main body 81B has a pair of wall portions 811, 812. The pair of wall portions 811, 812 are erected so as to face each other at both axial ends of a wall portion 813 that constitutes a flat plate-shaped bottom portion. The cross section of the base main body 81B is formed to be approximately U-shaped.

[0173] The pair of wall portions 811 and 812 are formed with insertion holes 8111 and 8121, respectively, through which the rotary shaft 24B is inserted. The pair of wall portions 811 and 812 are also formed with cutout holes 8112 and 8122, respectively, which connect the insertion holes 8111 and 8121 with the outer edges of the pair of wall portions 811 and 812.

[0174] As a result, with the mirror unit 22B fixed to the rotating shaft 24B, the rotating shaft 24B can be positioned at the position of the insertion holes 8111 and 8121 via the notched holes 8112 and 8122. If the notched holes 8112 and 8122 were not provided, with the mirror unit 22B positioned between the pair of wall portions 811 and 812, the rotating shaft 24B would be inserted into both the insertion holes 8111 and 8121 of the pair of wall portions 811 and 812 and the insertion hole of the mirror holder 222B. Further, a complicated assembly process would be required, such as fixing the rotating shaft 24B to the mirror holder 222B. In contrast, in this embodiment, the notched holes 8112 and 8122 are formed, so that the rotating shaft 24B, to which the mirror unit 22B has already been fixed, can be easily inserted into the insertion holes 8111 and 8121.

[0175] Bearings 82B and 83B are attached to mounting portions (not shown) provided in the insertion holes 8111 and 8121 of the pair of wall portions 811 and 812. The bearings 82B and 83B may be rolling bearings (e.g., ball bearings) or plain bearings for the base main body 81B. For example, if the bearings 82B and 83B are rolling bearings, they have a low coefficient of friction and can smoothly rotate the rotating shaft 24B, thereby improving the driving performance of the rotary reciprocating drive actuator 1B. As a result, the rotating shaft 24B is rotatably attached to the base main body 81B via the bearings 82B and 83B, and the mirror portion 22B, which is a movable object, is disposed between the pair of wall portions 811 and 812.

[0176] The bearings 82B and 83B are inserted from both axial sides of the rotating shaft 24B, and after the rotating shaft 24B is placed in the insertion holes 8111 and 8121, the bearings are attached to bearing attachment portions provided in the insertion holes 8111 and 8121. In this way, the rotating shaft 24B is rotatably attached to the base main body 81B via the bearings 82B and 83B.

[0177] A magnet 26B is fixed to one end of the rotary shaft 24B. The magnet 26B is disposed in a unit fixing portion 30B of the drive unit 10B, which will be described later, and is driven to rotate back and forth by the magnetic flux generated by the drive unit 10B.

[0178] As described above, in this embodiment, the rotation shaft 24B to which the mirror section 22B, which is the movable object, is attached is supported by a pair of walls 811, 812 of the base main body 81B so as to support the mirror section 22B from both sides. This provides stronger support for the mirror section 22B than when the rotation shaft 24B is supported in a cantilevered manner, improving impact resistance and vibration resistance.

[0179] <Drive unit 10B> 18 to 20, the drive unit 10B has a core assembly 40B including a core body K2 and coils 44, 45, a rotating shaft 24B, a magnet 26B, a first case 51B, a second case 52B, and a case-side bearing 53B. The drive unit 10B is fixed to the base main body 81B with the rotating shaft 24B disposed so as to span between a pair of wall portions 811, 812.

[0180] The core assembly 40B includes a core body K2, coils 44 and 45, as well as a rotation angle position holding portion 48B. In this embodiment, core assembly 40B is formed in the shape of a rectangular plate with magnetic poles 411a and 412a disposed inside.

[0181] <Core Body K2> The core body K2 has the same basic configuration as the core bodies K and K1. The core body K2 has a magnetic pole core 41B having a plurality of magnetic poles 411a, 412a and an interpole portion 415B, and a magnetic path core 42B that is magnetically coupled to and integrated with the magnetic pole core 41B and that forms a magnetic path together with the magnetic pole core 41B.

[0182] The magnetic pole core 41B and the magnetic path core 42B allow the magnetic flux generated when the coils 44, 45 are energized to pass through the multiple magnetic poles 411a, 412a. The magnetic pole core 41B and the magnetic path core 42B are laminated cores formed by laminating electromagnetic steel sheets (laminated members) such as silicon steel sheets. By making the core body K2 have a laminated structure, the magnetic pole core 41B and the magnetic path core 42B can be formed at low cost and with complex shapes.

[0183] <Magnetic pole core 41B> The magnetic pole core 41B has an integral structure including a plurality of rod-shaped members 411 and 412 each having a plurality of magnetic poles 411a and 412a at the tip thereof, an inter-pole portion 415B, and a connecting member 413B.

[0184] Rod-shaped bodies 411, 412 and magnetic poles 411a, 412a are similar to those of magnetic pole core 41 in embodiment 1, and therefore detailed description will be omitted. Rod-shaped bodies 411, 412 have magnetic poles 411a, 412a at their tips, which are arranged facing magnet 26B and have arc-shaped magnetic pole surfaces. Rod-shaped bodies 411, 412 extend parallel to each other from base ends 411b, 412b to their tips (including magnetic poles 411a, 412a), and are fitted with a plurality of coils 44, 45 around their intermediate portions, respectively.

[0185] When the coils 44, 45 are energized and magnetized, the magnetic poles 411a, 412a at the tips of the rod-shaped bodies 411, 412 produce polarities that correspond to the direction of energization. The rod-shaped bodies 411, 412 have the same thickness as the core body K2 (the length in the extension direction of the rotation shaft 24B), and are flush with the connecting body 413B on the left side but protrude beyond the connecting body 413B on the right side. The protruding portion of the rod-shaped body 411 on the right side is located within the magnetic path core 42B.

[0186] The portions of the magnetic poles 411a and 412a that face the magnet 26B have a curved shape that follows the outer circumferential surface of the magnet 26B. These curved shapes are arranged to face each other in a direction perpendicular to the extension direction of the rod-shaped bodies 411 and 412, for example. As in the first embodiment, the magnetic poles 411a and 412a have external dimensions that allow the bobbins 46 and 47 to be extrapolated and positioned to surround the rod-shaped bodies 411 and 412.

[0187] Connector 413B extends in a direction intersecting the parallel direction of rods 411, 412 at the base end of rods 411, 412 and interpole portion 415B, and connects rods 411, 412 and interpole portion 415B to each other.

[0188] Connecting body 413B mainly forms a magnetic path connecting the base ends of rod-shaped bodies 411 and 412 and the base ends of legs 421B and 422B of magnetic-path core 42B.

[0189] The connecting body 413B is formed in a rectangular column shape and extends in a direction perpendicular to the parallel direction of the rod-shaped bodies 411, 412 and the interpole portion 415B, and both ends thereof are formed so as to protrude laterally perpendicularly from the base ends 411b, 412b of the rod-shaped bodies 411, 412, respectively. Both ends of the connecting body 413B function as core fixing pieces for fixing the magnetic pole core 41B and the magnetic path core 42B, and the core fixing pieces have attachment holes 401 formed therein.

[0190] The fastening material 61B is inserted into the mounting hole 401, and is fixed by being inserted through the mounting holes of the magnetic path core 42B, and further through the mounting holes of the first case 51B or the second case 52B, which will be described later.

[0191] The connecting body 413B has a planar magnetic pole side contact surface 4130B that is in surface contact with the magnetic path side contact surface 4230 of the magnetic path core 42B. The magnetic pole side contact surface 4130B is provided on the entire surface of the portion of the connecting body 413B that faces the magnetic path core 42B. By joining the connecting body 413B with the magnetic pole side contact surface 4130B in surface contact with the magnetic path side contact surface 4230, the magnetic pole core 41B is joined to the magnetic path core 42B in a state where it is entirely stacked.

[0192] The inter-pole portion 415B is arranged in the same manner as the inter-pole portion 415 on the same magnetic circuit as the inter-pole portion 415 of the embodiment, and has the same function. That is, the inter-pole portion 415B is made of a magnetic material and is disposed opposite the magnet 26B at a predetermined distance in a direction perpendicular to the axial direction. The inter-pole portion 415B is disposed, for example, together with the magnetic poles 411a and 412a and the rotation angle position holder 48B so as to surround the magnet 26B on all four sides. The inter-pole portion 415B generates a magnetic attraction force between itself and the magnet 26B, thereby moving the magnet 26B to the rotation reference position.

[0193] Inter-pole portion 415B, together with rotational angle position holder 48B, generates a magnetic attractive force between itself and magnet 26, and together with rotational angle position holder 48, moves the poles of magnet 26B to opposing positions. Through this action, inter-pole portion 415B offsets the radial load on the magnet that is generated by the magnetic attractive force of rotational angle position holder 48B.

[0194] In the magnetic pole core 41B, the rod-shaped bodies 411, 412 and the connecting body 413B have an integral structure, so that the positional relationship between the multiple magnetic poles 411a, 412a does not change when assembling the rotary reciprocating drive actuator 1B.

[0195] That is, the magnetic pole core 41B, together with the magnetic path core 42B, constitutes the core body of the core assembly 40B, and the magnetic poles 411a, 412a and the inter-pole portion 415B are arranged in positions facing the magnet 26B to form the drive unit 10B. In this case, the magnetic poles 411a, 412a are positioned accurately facing each other without any misalignment.

[0196] <Magnetic path core 42B> The magnetic path core 42B has the same function as the magnetic path core 42, and is connected to the magnetic pole core 41B to form a magnetic path through which magnetic flux passes to the magnetic poles 411a and 412a when the coils 44 and 45 are energized.

[0197] The magnetic path core 42B faces the connecting body 413B in the extending direction of the rotation shaft 24B, and is assembled with the magnetic pole core 41B in a state where they are in surface contact with each other and the magnetic poles 411a, 412a are positioned around the rotation shaft 24B.

[0198] The magnetic path core 42B, together with the connecting body 413B, forms a magnetic path that is arranged around the rotation shaft 24B so as to surround the magnetic poles 411a, 412a and the coils 44, 45. That is, the magnetic path core 42B has an enclosing portion that surrounds the coils 44, 45, and a portion of the enclosing portion (the magnetic path-side connecting body 423B) is in surface contact with the connecting body 413B of the magnetic pole core 41B. With this configuration, the magnetic path core 42B has high strength and can stably position the magnetic poles 411a, 412a. Furthermore, because the magnetic path core 42B surrounds the coils 44, 45 in an annular shape, it is possible to prevent contact with the coils 44, 45 from the outside.

[0199] Magnetic path core 42B is connected to connecting body 413B, connecting base ends 411b, 412b of rod-shaped bodies 411, 412 of magnetic pole core 41B to base ends 421b, 422b of leg portions 421B, 422B. Due to this connection, the surrounding portion of magnetic path core 42B, together with connecting body 413B, surrounds magnetic poles 411a, 412a between magnetic poles 411a, 412a, coils 44, 45, and magnet 26B, and forms a magnetic circuit connecting magnetic poles 411a, 412a.

[0200] The surrounding portion of magnetic path core 42B has magnetic path-side connecting body 423B, which is in surface contact with magnetic pole-side contact surface 4130B of connecting body 413B, legs 421B and 422B, and bridge 427B. Magnetic path-side connecting body 423B connects the base ends of the pair of legs 421B and 422B. Mounting holes 402B are provided at both ends of magnetic path-side connecting body 423B. In connecting body 413B and magnetic path side connecting body 423B, a pair of legs 421B and 422B are connected to the portions extending outward from rod-shaped bodies 411 and 412, particularly to both end portions, in a state of contact and rising from one surface of both connecting bodies 413B and 423B. This allows the magnetic flux to pass mainly from both end portions through the pair of legs, bridge 427B, rod-shaped body 411, magnet 26B, and rod-shaped body 412 in connecting body 413B.

[0201] The magnetic path-side connecting body 423B has a magnetic path-side contact surface 4230 facing the connecting body 413B, and this magnetic path-side contact surface 4230 comes into contact with the magnetic pole-side contact surface 4130B of the connecting body 413B so as to overlap the entire surface. The magnetic path-side connecting body 423B can reduce the magnetic resistance at the joint portion of the magnetic pole-side contact surface 4130B of the connecting body 413B.

[0202] The legs 421B and 422B are spaced apart and extend parallel to the pair of rod-shaped bodies 411 and 412, sandwiching the pair of rod-shaped bodies 411 and 412. The legs 421B and 422B are joined at their base ends to extend from both ends of the magnetic path-side connecting body 423B in a direction intersecting with the magnetic path-side connecting body 423B. A bridge 427B is provided between the tip ends of the legs 421B and 422B.

[0203] The thickness of each of legs 421B, 422B (length in the direction of extension of rotation shaft 24B) is formed to be the same as, for example, the combined thickness of bridge 427B, rod-shaped bodies 411, 412, connecting body 413B, and magnetic path-side connecting body 423B. In legs 421B, 422B, the end faces of the base ends rising from magnetic path-side connecting body 423B are preferably formed to abut on connecting body 413B.

[0204] Bridge 427B is arranged parallel to magnetic path-side connecting body 423B. Bridge 427B is formed in a rectangular frame shape together with magnetic path-side connecting body 423B joined to connecting body 413B and legs 421B and 422B arranged parallel to each other and with base ends joined to magnetic path-side connecting body 423B. In this embodiment, bridge 427B is also provided with rotation angle position holder 48B having the same function as rotation angle position holder 48 provided on bridge 427.

[0205] In this embodiment, legs 421B and 422B are connected so as to abut against bridge 427B. Mounting holes 402B are provided in bridge 427B at portions that protrude to both sides from the joint between legs 421B and 422B. Fastening members 61 are inserted into mounting holes 402B and mounting holes 401B, respectively, and core assembly 40B is fixed to base main body 81B via these fastening members 61 when rotary reciprocating drive actuator 1B is assembled.

[0206] When rotary reciprocating drive actuator 1B is assembled, rotary shaft 24B is inserted into the space surrounded by magnetic poles 411a and 412a. Magnet 26B attached to rotary shaft 24B is positioned in this space, and magnetic poles 411a and 412a face magnet 26B at a precise position across air gap G.

[0207] The coils 44, 45 are wound around cylindrical bobbins 46, 47. A coil body consisting of the coils 44, 45 and the bobbins 46, 47 is extrapolated onto the rod-shaped bodies 411, 412 of the magnetic pole core 41B, so that the coils 44, 45 are arranged to wind around the rod-shaped bodies 411, 412. In this way, the coils 44, 45 are arranged adjacent to the magnetic poles 411a, 412a at the tip ends of the rod-shaped bodies 411, 412.

[0208] The winding direction of the coils 44, 45 is set so that magnetic flux is suitably generated from one of the magnetic poles 411a, 412a of the magnetic pole core 41B to the other when current is applied.

[0209] <Rotational angle position holding unit (an example of a first magnetic attraction member) 48B> When the rotary reciprocating drive actuator 1B is assembled, the rotational angle position holder 48B is incorporated into the core assembly 40B so as to face the magnet 26B across the air gap G. The rotational angle position holder 48B is attached, for example, to the bridge portion 427B of the magnetic path core 42B (the portion above the rod-shaped bodies 411, 412 of the magnetic pole core 41B) in an orientation in which the magnetic pole faces the magnet 26B.

[0210] Rotation angle position holder 48B is formed of, for example, magnet 26B, and generates a magnetic attraction force between itself and magnet 26B, attracting magnet 26B. That is, rotation angle position holder 48B, together with rod-shaped bodies 411 and 412, forms a magnetic spring between itself and magnet 26B. This magnetic spring holds the rotation angle position of magnet 26B, i.e., the rotation angle position of rotation shaft 24B, at the rotation reference position when coils 44 and 45 are not energized (when not energized).

[0211] The first case 51B and the second case 52B are made of an electrically conductive material and function as electromagnetic shields. The first case 51B and the second case 52B are arranged on both axial sides of the core body K2. The first case 51B and the second case 52B can suppress noise from entering the core body K2 from the outside and noise from the core body K2 to the outside.

[0212] The first case 51B and the second case 52B are preferably made of an aluminum alloy. Aluminum alloys offer a high degree of design freedom and can easily impart the desired rigidity. Therefore, they are suitable for use when the first case 51B functions as a support for the rotating shaft 24B.

[0213] The rotating shaft 24B is rotatably attached to the first case 51B via a case-side bearing 53B. The case-side bearing 53B is disposed in a bearing attachment portion (not shown) that is continuous with a through-hole 511B formed in the first case 51B. The case-side bearing 53B easily and rotatably attaches the end of the rotating shaft 24B on the side where the magnet 26B is disposed to the first case 51B. The case-side bearing 53B is, for example, a rolling bearing or a sliding bearing, and has the same function as the bearings 82B and 83B. The case-side bearing 53B, together with the bearing 82B of the wall portion 813, supports the rotating shaft 24B on both sides of the magnet 26B so that the rotating shaft 24B can rotate back and forth.

[0214] The second case 52B positions and joins the core assembly 40B to the wall 813 of the base body 81B. The second case 52B is fixed to the first case 51B via the fastening material 61B, sandwiching the core body K2 therebetween, and is positioned and fixed to the wall 813 via the fastening material 62B.

[0215] The second case 52B has an insertion hole 521B that is larger than the outer shape of the magnet 26B. The rotating shaft 24B to which the magnet 26B is attached is inserted into the core assembly 40B through the insertion hole 521B of the second case 52B.

[0216] The core body K2 is sandwiched between the first case 51B and the second case 52B, and fixed by the fastening material 61 to be integrated as the core assembly 40B. The core assembly 40B is also fixed to the left wall 811 of the base main body 81B by the fastening material 62B to be integrated with the base main body 81B.

[0217] The magnet 26B is a ring-shaped magnet in which south poles 261 and north poles 262 are arranged alternately in the circumferential direction. The magnet 26B is attached to the circumferential surface of the rotating shaft 24B so as to be located in the space surrounded by the magnetic poles 411a, 412a of the core body K2 when the rotary reciprocating drive actuator 1B is assembled. When current is applied to the coils 44, 45, the rod-shaped bodies 411, 412 and the magnetic path core 42B are excited, and the magnetic poles 411a, 412a develop polarities according to the direction of current application, generating magnetic forces (attraction and repulsion) between the magnetic poles 411a, 412a and the magnet 26B.

[0218] In this embodiment, magnet 26B, like magnet 26, is magnetized with different polarities with a plane along the axial direction of rotation shaft 24B as the boundary. That is, magnet 26B is a two-pole magnet magnetized so as to be equally divided into an S pole 261 and an N pole 262. The number of magnetic poles of magnet 26B (two in this embodiment) is equal to the number of magnetic poles 411a, 412a of core body K2. Note that magnet 26B may be magnetized with two or more poles depending on the amplitude during movement. In this case, the magnetic pole portions of core body K2 are provided to correspond to the magnetic poles of magnet 26B.

[0219] The magnetic circuit configuration of this embodiment, including magnet 26B, is the same as in embodiment 1, and therefore description thereof will be omitted. In drive unit 10B, the portion of rotating shaft 24B where magnet 26B is located is supported at two points by first case 51B and case-side bearing 53B and bearing 82B of left wall 811. As a result, even if the magnetic attractive force between magnet 26B and rotational angle position holder 48B becomes large, the two-point support structure, in addition to the magnetic attractive force of inter-pole portion 415B, ensures linearity extending in the axial direction of rotating shaft 24B.

[0220] In other words, if the portion of the rotation shaft 24B where the magnet 26B is located is supported only by the left wall portion 813, it will be in a cantilevered state. In this case, if the magnetic attraction force between the magnet 26B and the rotation angle position holder 48B becomes large, a load will be applied to the rotation shaft 24B that will displace it toward the rotation angle position holder 48B, which may cause it to bend toward the rotation angle position holder 48B and reduce its linearity. This problem does not occur in the present embodiment, and the linearity of the rotation shaft 24B can be maintained, allowing the rotation shaft 24B to rotate appropriately around its axis without wobbling.

[0221] The driving principle of the rotary reciprocating actuator 1B is the same as that of the rotary reciprocating actuator 1 based on the above formulas (1), (2), and (3), and therefore a description thereof will be omitted.

[0222] (Embodiment 3) Fig. 20 is an external perspective view of a rotary reciprocating drive actuator 1C according to the third embodiment, Fig. 21 is an exploded perspective view of the top side of the rotary reciprocating drive actuator 1C, and Fig. 22 is an exploded perspective view of the bottom side of the rotary reciprocating drive actuator 1C.

[0223] The rotary reciprocating actuator 1C shown in FIGS. 20 to 22 is a rotary reciprocating actuator that supports a movable object so that it can rotate back and forth, especially when the movable object is larger than the rotary reciprocating actuator 1.

[0224] The rotary reciprocating drive actuator 1C differs from the rotary reciprocating drive actuator 1 in that it has an auxiliary frame 80C, the configuration of the first shaft support 50C to which the auxiliary frame 80C is attached, and the length of the rotary shaft 24C, but the other configurations are similar. Therefore, the following will only explain the configuration of the rotary reciprocating drive actuator 1C that is different from the rotary reciprocating drive actuator 1, and will not explain the other similar configurations.

[0225] The rotary reciprocating actuator 1C has the same functions as the rotary reciprocating actuator 1, and includes a drive unit 10C, a mirror section 22C, an auxiliary frame 80C, and an angle sensor section .

[0226] The drive unit 10C differs from the drive unit 10 in the configuration of the first shaft support 50 in the unit fixing portion 30. In the drive unit 10C, the top surface of the support body portion 52C of the first shaft support 50C of the unit fixing portion 30C has a frame fixing surface 57 to which one wall portion 811 of a pair of walls 811, 812 of the auxiliary frame 80C is fixed.

[0227] In the drive unit 10C, the core body K3 is formed in the same manner as the core body K. The core body K3 has a magnetic pole core 41C configured in the same manner as the magnetic pole core 41, and has magnetic poles 411a, 412a and an interpole portion 415, and a magnetic path core 42C configured in the same manner as the magnetic path core 42. These have the same functions as those in the first embodiment with the same names and reference numerals, and since they have the same functions, a description thereof will be omitted. In particular, the interpole portion 415 can obtain the same effects as in the first embodiment. The driving principle of the rotary reciprocating drive actuator 1C is the same as that of the rotary reciprocating drive actuator 1 based on the above formulas (1), (2), and (3), and therefore a description thereof will be omitted.

[0228] An auxiliary frame 80C is fixed to the frame fixing surface 57 via a fastening material 36. Compared to the drive unit 10, the drive unit 10C has a longer rotation shaft 24C of the unit movable part 20, and is configured such that the core assembly 40 is sandwiched between a first shaft support body 50C and a second shaft support body 60C.

[0229] The rotation shaft 24C has a length sufficient to bridge between the wall portions 811 and 812 of the auxiliary frame 80C, and is disposed so as to extend from the insertion hole 822 to the insertion hole 821.

[0230] The rotary reciprocating actuator 1C has an auxiliary frame 80C attached to a drive unit 10C, and supports a mirror portion 22C, which is a movable object, so that the mirror portion 22C can rotate back and forth.

[0231] The auxiliary frame 80C is a member having a substantially U-shaped cross section and a pair of wall portions 811, 812. The pair of wall portions 811, 812 are formed with insertion holes 821, 822, respectively, through which the rotation shaft 24C is inserted. A rotation support shaft portion 39, through which the tip of the rotation shaft 24C is rotatably inserted, is fitted into the insertion hole 821. Furthermore, the pair of wall portions 811, 812 are formed with notched holes 831, 832, which connect the insertion holes 821, 822 to the outer edges of the wall portions 811, 812, respectively.

[0232] The rotation support shaft portion 39 may be configured in any way as long as it can rotatably support the inserted rotation shaft 24C, and may be configured with a slide bearing, a resin bushing, etc. The rotation support shaft portion 39 supports the tip portion 242 of the rotation shaft 24C, to which the mirror portion 22C is attached, between a pair of wall portions 811, 812 of the auxiliary frame 80C.

[0233] This allows the rotation shaft 24C to be disposed at the position of the rotation shaft 24C via the cutout holes 831 and 832, with the mirror portion 22C fixed to the rotation shaft 24C. Furthermore, the rotation shaft 24C is disposed between the walls 811 and 812 of the auxiliary frame 80C.

[0234] If the cutout holes 831 and 832 were not provided, a complicated assembly process would be required, in which the mirror section 22C is disposed between the pair of wall sections 811 and 812, the rotating shaft 24C is inserted into both of the insertion holes 821 and 822 of the wall sections 811 and 812, and then the rotating shaft 24C and the mirror section 22C are fixed together. In contrast, in the present embodiment, the cutout holes 831 and 832 are provided, so that the rotating shaft 24C, to which the mirror section 22C has been fixed in advance, can be easily inserted into the insertion holes 821 and 822.

[0235] With this configuration, even when the movable object is large, that is, when the mirror portion 22C is supported by a cantilevered drive unit 10C, the behavior of the mirror portion 22C can be stabilized, shock resistance and vibration characteristics can be ensured, and the mirror portion 22C can be supported stably so that it can rotate back and forth freely.

[0236] (Scanner System 100) FIG. 23 is a block diagram showing the configuration of the main parts of a scanner system 100 using the rotary reciprocating actuator 1. As shown in FIG.

[0237] In addition to the rotary reciprocating actuator 1, the scanner system 100 has a laser emission unit 101, a laser control unit 102, a drive signal supply unit 103, and a position control signal calculation unit 104. Note that the scanner system 100 may employ rotary reciprocating actuators 1B and 1C instead of the rotary reciprocating actuator 1. Furthermore, regardless of whether they are applied to the scanner system 100, in the configuration of the rotary reciprocating actuators 1, 1B, and 1C, the respective core assemblies or core bodies may be replaced with rotary reciprocating actuators using core assembly 40A or core body K1.

[0238] The laser emitting unit 101 includes, for example, an LD (laser diode) serving as a light source, and a lens system for converging the laser light output from the light source. The laser control unit 102 controls the laser emitting unit 101. The laser light emitted from the laser emitting unit 101 is incident on a mirror 221 of the rotary reciprocating actuator 1.

[0239] The position control signal calculation unit 104 references the angular position of the rotation shaft 24 (mirror 221) acquired by the angle sensor unit 70 and the target angular position, and generates and outputs a drive signal that controls the rotation shaft 24 (mirror 221) to be at 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 shaft 24 (mirror 221) and a signal indicating the target angular position converted using sawtooth waveform data or the like stored in a waveform memory (not shown). The position control signal calculation unit 104 outputs the generated position control signal to the drive signal supply unit 103.

[0240] Based on the position control signal, the drive signal supply unit 103 supplies a drive signal to the coils 44, 45 of the rotary reciprocating actuator 1 so that the angular position of the rotary shaft 24 (mirror 221) becomes a desired angular position. This allows the scanner system 100 to emit scanning light from the rotary reciprocating actuator 1 to a predetermined scanning area.

[0241] In addition, even in the case of the rotary reciprocating drive actuator 1C of embodiment 3, in which the first shaft support 50C is configured in a manner substantially similar to the first shaft support 50 and the tip of the rotary shaft 24C is separated from the first bearing 54, the rotary shaft 24C can be suitably supported by the auxiliary frame 80C and the rotary support shaft portion 39.

[0242] The core body K is composed of a magnetic pole core 41 and a magnetic path core 42, which are separate bodies, and the magnetic poles 411a, 412a of the magnetic pole core 41 are integrally formed at positions facing the outer periphery of the magnet 26. This allows for easy manufacturing without reducing the accuracy of arrangement of the multiple magnetic poles 411a, 412a, even if the shape of the core body K having the magnetic pole core 41 and the magnetic path core 42 is complex.

[0243] The invention made by the inventor has been specifically described above based on an embodiment, but the present invention is not limited to the above embodiment and can be modified within the scope of the gist thereof.

[0244] For example, in the embodiment, the movable object is the mirror section 22, but the movable object is not limited to this. The movable object may be, for example, an imaging device such as a camera.

[0245] Furthermore, for example, in the embodiment, the rotary reciprocating drive actuator 1 is resonantly driven, but the present invention can also be applied to non-resonant driving.

[0246] The configuration of the unit fixing part 30 is not limited to that described in the embodiment. For example, the core may have multiple magnetic poles that are excited by energizing the coil to generate polarity, and when the rotating shaft is attached to the unit fixing part, the magnetic poles and the outer surface of the magnet may face each other via an air gap. Furthermore, the coil may have a configuration that generates a magnetic flux that is preferably directed from one magnetic pole of the core to the other when energized.

[0247] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Industrial Applicability]

[0248] The present invention is suitable for, for example, LiDAR devices and scanner systems. [Explanation of symbols]

[0249] 1, 1B, 1C Rotary and reciprocating drive actuator 10, 10B, 10C drive units 15 Positioning recess 20 Unit moving parts 22, 22B, 22C mirror section 24, 24B, 24C Rotating shaft 25 spacer 26, 26B magnet 27 Preload spring 27a Washer 28 Shaft support ring 30, 30B, 30C Unit fixing part 32, 33, 34, 36 Fastening material 39 Rotating support shaft 40, 40A, 40B core assembly 41, 41A, 41B, 41C magnetic pole core 42, 42A, 42B, 42C magnetic core 44, 45 coils 46, 47 Bobbin 48, 48A, 48B Rotation angle position holding portion (first magnetic attraction member) 49 Magnetic pole face 50, 50C 1st shaft support 51B Case 1 52, 52C, 62 Support body part 52B Second Case 53B Case side bearing 54 No. 1 bearing 56 Mounting leg 57 Frame fixing surface 58 Core holding part 60, 60C 2nd shaft support 61, 61B, 62B Fastening material 64 Second bearing 70 Angle sensor unit 71 Circuit Board 73 Light Sensor 74 Encoder Disk 75 Stopper part 76 Protrusion 77 Regulatory Department 78 Sensor mounting part 79 Circuit Board 80B base 80C auxiliary frame 81B base body 82B, 83B bearings 100 Scanner System 101 Laser emission unit 102 Laser control unit 103 Drive signal supply unit 104 Position control signal calculation unit 221, 221B mirror 222, 222B mirror holder 223 Insertion hole 242 Tip 261, 262 poles 263, 264 Magnetic pole switching unit 401, 401B, 402B mounting holes 402 Engagement recess 403, 404, 405 Positioning holes 411, 412 Rod-shaped body 411a, 412a magnetic pole 411b, 412b, 415b, 421b, 422b proximal end 413 Connection frame 413B Connector 415, 415B Interpolator (second magnetic attraction member) 420, 420A Enclosure 421, 422 Frame side 421B, 422B legs 423, 423A Frame bottom 423B Magnetic path side connector 427, 427A, 427B bridge section 501, 502, 601, 602, positioning holes 503, 603 Fastening hole 521, 621 through holes 521B, 821, 822, 8111, 8121 Insertion holes 811, 812, 813 Wall section 831, 832, 8112, 8122 Notched holes 4130, 4130B magnetic pole side contact surface 4131 Connection edge 4132, 4133 Projecting side 4150 Interpolated surface 4201, 4230 Magnetic path side contact surface 4202 Notch 5211, 6211 bearing mounting part HF magnetic attraction force (second magnetic attraction force) K, K1, K2, K3 core body KF magnetic attraction force (first magnetic attraction force)

Claims

1. a movable body having a magnet fixed to a shaft portion to which a movable object is connected, the movable body being arranged so as to be rotatable back and forth around the shaft portion; a fixed body arranged on the outer periphery of the magnet to face a core body having a plurality of coils and a plurality of magnetic poles, a first magnetic attraction member that generates, between itself and the magnet, a first magnetic attraction force that defines the rotation center position of the reciprocating rotation of the movable body, and a second magnetic attraction member that generates, between itself and the magnet, a second magnetic attraction force that offsets the axial radial load acting on the movable body by the first magnetic attraction force; and By energizing the plurality of coils, a magnetic flux passing through the plurality of magnetic poles is generated, and the movable body is rotated back and forth around the axis of the shaft portion with the rotation center position as a reference by electromagnetic interaction between the magnetic flux and the magnet, The core body is a plurality of rod-shaped bodies each having the plurality of magnetic poles at a tip end portion facing the magnet, extending parallel to one another from a base end portion to the tip end portion, and each having the plurality of coils exteriorly mounted at an intermediate portion thereof; The second magnetically attractive member is disposed in parallel with the plurality of rod-shaped bodies and extends between the rod-shaped bodies, and is disposed on the opposite side of the first magnetically attractive member with respect to the center of the shaft portion. Rotary reciprocating drive actuator.

2. the second magnetic attraction member is a magnetic body integrally provided on the core body having the plurality of magnetic poles; 2. The rotary reciprocating drive actuator according to claim 1.

3. The core body having the plurality of magnetic poles is a pair of legs joined to the base ends of the rod-shaped bodies, respectively, and extending along the parallel direction of the rod-shaped bodies; a bridge portion provided between the tip portions of the pair of legs; and the first magnetic attraction member is provided on the bridge portion, The second magnetically attractive member is disposed between the magnetic poles.

3. The rotary reciprocating actuator according to claim 1 or 2.

4. The core body is a magnetic pole core having an integral structure including the plurality of rod-shaped bodies and a connecting body joined to the base end portion of the rod-shaped bodies and extending in a direction intersecting the parallel direction of the plurality of rod-shaped bodies; a magnetic path core including the pair of legs and the bridge portion, and constituting a magnetic path of the magnetic flux together with the magnetic pole core; and The second magnetic attraction member is provided integrally with the connecting body and extends along the parallel direction of the rod-shaped body.

4. The rotary reciprocating actuator according to claim 3.

5. The plurality of coils are surrounded by the pair of legs, the bridge, the base ends of the plurality of rod-shaped bodies, and the connecting body.

5. The rotary reciprocating actuator according to claim 4.

6. The plurality of magnetic poles and the second magnetic attraction member are made of laminated members.

6. A rotary reciprocating drive actuator according to any one of claims 1 to 5.

7. the plurality of magnetic poles are two poles, and the magnet has two different magnetic poles corresponding thereto, and the magnetic pole switching portion of the magnet is provided so as to be disposed in a position symmetrically opposite to each of the plurality of magnetic poles when the magnet is held at the rotation center position by the first magnetic attraction member; 7. A rotary reciprocating drive actuator according to any one of claims 1 to 6.

8. The first magnetic attraction member is a magnet. A rotary reciprocating drive actuator according to any one of claims 1 to 7.

9. The first magnetic attraction member is a magnetic material. A rotary reciprocating drive actuator according to any one of claims 1 to 7.

10. a pair of shaft supports arranged to sandwich the plurality of magnetic poles in the extending direction of the shaft portion, and rotatably supporting the shaft portion via bearings on both sides of the plurality of magnetic poles, 10. A rotary reciprocating drive actuator according to any one of claims 1 to 9.

11. the movable object is connected to one end of the shaft portion protruding from one of the pair of shaft supports, a rotation support shaft portion fixed to a support wall portion arranged to sandwich the movable object between the one shaft support and the tip of the movable object fixed to one end of the shaft portion; 11. The rotary reciprocating drive actuator of claim 10.

12. The rotary reciprocating actuator according to claim 1 , wherein the movable object is a mirror that reflects scanning light.

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