Rotary reciprocating actuator

Abstract

To reduce assembly time with a structure that ensures high assembly accuracy and stably drives a movable body.SOLUTION: A rotary reciprocating drive actuator includes: a main body unit including a movable body including a shaft part to which a movable object is connected at one end side and to which a magnet is fixed at the other end side, and a base part including a pair of wall parts disposed to sandwich the movable object, and rotatably supporting the shaft part by the pair of wall parts in a state where the other end side of the shaft part protrudes from one wall part of the pair of wall parts; a core assembly including a core body including a plurality of magnetic poles facing an outer periphery of the magnet to sandwich the magnet, a coil body wound around the core body and generating a magnetic flux interacting with the magnet through energization to cause a reciprocating rotation of the movable body, and a magnet position holding part generating a magnetic attraction force between the magnet position holding part and the magnet to define a reference position of the reciprocating rotation; and a connecting surface part integrally disposed on one end side of the core assembly, and attached to one wall part in a state where the shaft part is inserted into an opening and the magnet is disposed in the core assembly.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] Conventionally, rotary reciprocating actuators have been used as actuators in optical scanning devices such as multifunction printers and laser beam printers. Specifically, rotary reciprocating actuators achieve optical scanning of an object by changing the reflection angle of the laser beam by reciprocating the rotation of the scanner's mirror.

[0003] Patent Document 1 discloses a type of rotary reciprocating actuator using a galvanometer motor. Various types of galvanometer motors are known, including the type with the structure disclosed in Patent Document 1, and coil-movable types in which the coil is attached to a mirror.

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

[0005] [Patent Document 1] Patent No. 4727509 [Overview of the project] [Problems that the invention aims to solve]

[0006] Incidentally, in the beam scanner described in Patent Document 1, a rotating axis mirror is mounted rotatably between a pair of opposing wall-shaped bearing holders that rise up from a fixed base at a distance from it. A magnetic circuit having a permanent magnet and a core is arranged on the back surface of this mirror.

[0007] As described above, since the magnetic circuit is located on the back surface of the mirror supported via a rotating shaft, it is difficult to assemble the magnetic circuit and the mirror support structure via the rotating shaft simultaneously, especially when high-precision assembly is required. Therefore, these assembly operations must be performed sequentially, and there is a need to shorten the assembly time of the rotary reciprocating drive actuator.

[0008] This invention was made in consideration of the above points, and provides a rotary reciprocating drive actuator that has a structure that ensures high assembly precision and stable operation, while also reducing assembly time. [Means for solving the problem]

[0009] One embodiment of the rotary reciprocating actuator of the present invention is: A movable body having a shaft portion to which a movable object is connected at one end and a magnet is fixed at the other end, and a pair of wall portions arranged to sandwich the movable object, the shaft portion The aforementioned A main body unit having a base portion that rotatably supports the shaft portion with the pair of walls, with the other end portion protruding from one of the pair of walls, A core body having a plurality of magnetic poles facing each other on the outer circumference of the magnet so as to sandwich the magnet, and a winding around the core body It has a coil body, and the coil body The current is generated by the application of electricity, causing the movable body to reciprocate. The drive unit that drives, Equipped with, The drive unit includes the core body and the A core assembly having a coil body and a magnet position holding part that generates a magnetic attractive force between itself and the magnet to define the reference position of the reciprocating rotation, A connecting surface portion is integrally provided on one end side of the core assembly, and is attached to the one wall portion with the shaft portion inserted through the opening and the magnet positioned inside the core assembly, An angle sensor unit for detecting the rotation of the shaft portion is provided, and a sensor placement unit is provided on the opposite side of the connection surface portion in the axial direction from the core assembly, so as to cover the core assembly. The core assembly is configured to be held and fixed between the sensor placement portion and the connection surface portion. Take it. [Effects of the Invention]

[0010] According to the present invention, it is possible to shorten the assembly time while having a structure that ensures high assembly accuracy and drives stably.

Brief Description of the Drawings

[0011] [Figure 1] External perspective view of the rotary reciprocating drive actuator according to Embodiment 1 of the present invention. [Figure 2] Longitudinal sectional view passing through the axis of the rotary reciprocating drive actuator. [Figure 3] In FIG. 2, end view of the A-A line portion where the left member is removed from the front end face of the drive unit. [Figure 4] Exploded perspective view of the rotary reciprocating drive actuator. [Figure 5] Front side perspective view in a state where the drive unit is removed from the main body unit. [Figure 6] Rear side perspective view in a state where the drive unit is removed from the main body unit. [Figure 7] Perspective view of the main body unit. [Figure 8] Cross-sectional view taken along the B-B line in FIG. 7. [Figure 9] Enlarged view of the preloading spring. [Figure 10] View showing a wave spring which is a modified example of the preloading spring. [Figure 11] Enlarged perspective view of the front end portion of the rotary reciprocating drive actuator. [Figure 12] Perspective view showing the inside of the top cover with the sensor board removed in FIG. 11. [Figure 13] Arrow view cross-sectional view taken along the C-C line in FIG. 11. [Figure 14] Exploded perspective view of the drive unit. [Figure 15] Perspective view of the coil body. [Figure 16] Exploded view of the bobbin. [Figure 17] Perspective view showing the connection state of the coils in the coil body. [Figure 18]Front and side perspective view of the bottom cover. [Figure 19] Cross-sectional view taken along the DD line in Figure 11. [Figure 20] This diagram illustrates the operation of the magnetic circuit of a rotary reciprocating actuator. [Figure 21] A longitudinal cross-sectional view showing a modified example 1 of a rotary reciprocating actuator. [Figure 22] Exploded perspective view of a modified example 1 of a rotary reciprocating actuator. [Figure 23] External perspective view of a modified example 2 of the rotary reciprocating actuator. [Figure 24] A perspective view of the main unit of a modified example 2 of a rotary reciprocating drive actuator. [Figure 25] This is a front view showing the main components of the drive unit in a modified example 2 of the same rotary reciprocating drive actuator. [Figure 26] A perspective view of a modified example 2 of a rotary reciprocating drive actuator to be attached to a product. [Figure 27] External perspective view of a modified example 3 of the rotary reciprocating drive actuator. [Figure 28] External perspective view of the top cover of modified example 3 of the rotary reciprocating drive actuator. [Figure 29] A perspective view showing a modified example 3 of a rotary reciprocating actuator to be attached to a product. [Figure 30] External perspective view of the bottom cover of modified example 4 of the rotary reciprocating actuator. [Figure 31] A perspective view showing a modified example 4 of a rotary reciprocating actuator to be attached to a product. [Figure 32] A diagram showing the main components of a scanner system using a rotary reciprocating actuator. [Figure 33] Figures 33A and 33B show a front view and a right side view of a modified example of the magnet (modification 1). [Figure 34] Figures 34A and 34B show a front view and a right side view of modified magnet 2. [Figure 35] Figures 35A and 35B show a front view and a right side view of a modified example of the magnet (modification 3). [Figure 36] Figures 36A and 36B show a front view and a right side view of modified magnet 4. [Figure 37] This figure shows a core assembly of a rotary reciprocating actuator having a modified magnet (modification 4). [Modes for carrying out the invention]

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0013] Figure 1 is an external perspective view of the rotary reciprocating drive actuator 1 according to Embodiment 1 of the present invention, and Figure 2 is a longitudinal cross-sectional view passing through the axis of the rotary reciprocating drive actuator 1. Figure 3 is an end view of the portion along line AA in Figure 2, where the left-side member has been removed from the front end face to show the inside of the drive unit 4, and Figure 4 is an exploded perspective view of the rotary reciprocating drive actuator 1.

[0014] The rotary reciprocating actuator 1 is used, for example, in a LiDAR (Laser Imaging Detection and Ranging) device. Furthermore, the rotary reciprocating actuator 1 can also be applied to optical scanning devices such as multifunction printers and laser beam printers.

[0015] The rotary reciprocating actuator 1 comprises, broadly speaking, a movable body 10, a base portion 21 that rotatably supports the movable body 10, and a drive unit 4 that reciprocates and rotates the movable body 10 relative to the base portion 21. The base portion 21 and the drive unit 4 constitute a fixed body 20 that rotatably supports the movable body 10.

[0016] Furthermore, in the rotary reciprocating actuator 1, the movable body 10 is attached to the base portion 21 to form the main body unit 2, and the rotary reciprocating actuator 1 has a drive unit 4 at one end of the main body unit 2.

[0017] Figure 5 is a front perspective view with the drive unit 4 removed from the main unit 2, and Figure 6 is a rear perspective view with the drive unit 4 removed from the main unit 2.

[0018] As shown in Figures 5 and 6, the main unit 2, which has the movable body 10 attached to the base 21, and the drive unit 4 are attached by a fastening member 81. The fastening member 81 can be any material that can secure both parts together, but for example, screws, bolts, or bolts and nuts may be used.

[0019] The movable body 10 has a rotating shaft 13, a mirror section 12, and a movable magnet (hereinafter simply referred to as "magnet") 32. Details of the magnet 32 ​​will be described in detail along with the drive unit 4, which will be described later.

[0020] The mirror section 12 is a movable object in the rotary reciprocating actuator 1 and is connected to the rotation shaft 13. The mirror section 12 is formed, for example, by attaching a mirror 121 to one surface of a mirror holder 122. The rotation shaft 13 is inserted through the insertion hole 122a of the mirror holder 122 and fixed in place. The mirror section 12 reflects scanning light.

[0021] Figure 7 is a perspective view of the main unit, and Figure 8 is a cross-sectional view of Figure 7 along line BB. As shown in Figures 4 to 8, the base portion 21 has a flat bottom portion 213 and a pair of wall portions 211 and 212 that are spaced apart from each other. The bottom portion 213 is flat and extends in the axial direction, with the pair of wall portions 211 and 212 erected at each end of it so as to face each other. The cross-section of the base portion 21 is formed by the bottom portion 213 and the pair of wall portions 211 and 212 to be approximately U-shaped.

[0022] The pair of wall sections 211 and 212 are arranged to sandwich the mirror section 12. Each of the pair of wall sections 211 and 212 is rectangular in shape, and through holes 211a and 212a are formed in the center of each. Bearings 22 and 23 are fitted into the through holes 211a and 212a, and the rotating shaft 13 is inserted through the bearings 22 and 23.

[0023] Furthermore, the through holes 211a and 212a are each provided with a counterbore at the axially outer opening edge, which has a larger diameter than the through portion. The flanges 224 and 234 of the bearings 22 and 23 are fitted into these counterbores.

[0024] In bearings 22 and 23, flanges 224 and 234 are provided on one opening edge of the donut-shaped bearing bodies 222 and 232. The bearings 22 and 23 are fitted into the walls 211 and 212 of the base portion 21 from the axial outside, causing the flanges 224 and 234 to fit into the counterbore. The bearings 22 and 23 are fixed to the base portion 21 in a manner that prevents them from coming loose in the fitting direction.

[0025] As a result, the bearing bodies 222 and 232 of the bearings 22 and 23 do not protrude outward from the walls 211 and 212 relative to the base portion 21, making it possible to thin the walls 211 and 212 of the base portion 21, and consequently shortening and miniaturizing the overall length of the rotary reciprocating drive actuator 1.

[0026] Furthermore, the flanges 224 and 234 of the bearings 22 and 23 are fitted into the counterbores on the axially outer side (outer surface side of the wall portions 211 and 212) of the through holes 211a and 212a. This allows the fitting state between the flanges 224 and 234 and the through holes 211a and 212a to be easily visually inspected and measured from the outside of the wall portions 211 and 212 during the assembly of the main unit 2.

[0027] The bearings 22 and 23 may consist of rolling bearings (e.g., ball bearings) or sliding bearings for the base portion 21. For example, if the bearings 22 and 23 are rolling bearings, the coefficient of friction is low, and the rotating shaft 13 can be rotated smoothly, thereby improving the driving performance of the rotary reciprocating drive actuator 1. As a result, the rotating shaft 13 is rotatably attached to the base portion 21 via the bearings 22 and 23, and the mirror portion 12, which is the movable object, is positioned between the pair of wall portions 211 and 212.

[0028] The rotating shaft 13 is inserted through the bearings 22 and 23, and both ends of the rotating shaft 13 protrude outward from the bearings 22 and 23 in the axial direction. The bearings 22 and 23 support the rotating shaft 13 on the base portion 21 so that it can rotate around its axis.

[0029] At one end of the rotating shaft 13, the movable mirror portion 12 is fixed to a portion inserted between a pair of walls 211 and 212 of the base portion 21, and a magnet 32 ​​is fixed to the other end 132 of the rotating shaft 13. In this way, the rotating shaft 13 is pivotally supported by the pair of walls 211 and 212 of the base portion 21. Since the base portion 12 supports the mirror portion 12, which is positioned between the pair of walls 211 and 212, from both sides via the rotating shaft 13, it can support the mirror portion 12 more firmly than a configuration in which the rotating shaft is cantilevered and the rotating shaft is supported by the mirror portion 12, thereby improving impact resistance and vibration resistance.

[0030] The magnet 32 ​​is located inside the drive unit 4, which will be described later, and is driven to reciprocate rotation by the magnetic flux generated by the drive unit 4. The rotating shaft 13 causes the mirror section 12 to reciprocate rotation due to the mutual electromagnetic action between the drive unit 4 and the magnet 32.

[0031] In the rotating shaft 13, a retaining ring 14 is fitted into a fitting groove 133 at one end 131 that protrudes outward from the bearing 23, and this retaining ring 14 restricts the movement of the rotating shaft 13 toward the other end 132.

[0032] A cylindrical stopper portion 15 is externally fitted onto the rotating shaft 13 at the portion between the mirror holder 122 of the mirror portion 12 and the wall portion 212 on the end 131 side of the pair of wall portions.

[0033] The stopper portion 15 is fixed to the rotating shaft 13. The movement of the rotating shaft 13 toward one end 131 is restricted by the bearing 23, and the movement of the rotating shaft 13 toward the other end 132 is restricted by the retaining portion 14. The mirror portion 12, which is fixed to the rotating shaft 13, is restricted from moving axially toward the other end 132 relative to the base portion 21 via the retaining portion 14.

[0034] The stopper portion 15, via the mirror portion 12, prevents the rotating shaft 13 from coming out of the bearing 23 towards the axial end 131, that is, outwards.

[0035] The stopper portion 15, together with the retaining portion 14, restricts the axial movement of the movable body 10, including the mirror portion 12, the rotating shaft 13, and the magnet 32, to a predetermined range including tolerances, thereby preventing it from coming off the base portion 21.

[0036] The rotating shaft 13 is positioned on the base portion 21 such that its other end 132 side passes through the bearing 22 and protrudes to the outside of the base portion 21 from the wall portion 211. The portion protruding from the wall portion 211 passes through the inside of the drive unit 4.

[0037] The magnet 32, which is fixed to the other end 132 of the rotating shaft 13, is positioned in a part that protrudes outward from the wall portion 211 of the base portion 21.

[0038] In the rotating shaft 13, a preload spring 35, an annular receiving portion 37, and a magnet 32 ​​are arranged in order from the wall portion 211 side at the portion that protrudes from the wall portion 211 towards the other end portion 132.

[0039] The preload spring 35 expands and contracts in the axial direction, biasing the bearing 22 in the axial direction. The preload spring 35 is a cylindrical coil spring having a predetermined length L1 corresponding to the space in which the preload spring 35 is arranged, as shown in Figure 9, and having flat surfaces formed at both ends that are spaced apart in the predetermined longitudinal direction.

[0040] The preload spring 35 is positioned externally on the rotating shaft 13 and biases the magnet 32 ​​in a direction that moves it away from the bearing 22 which is fitted into the wall portion 211. The preload spring 35 is interposed between the annular receiving portion 37 adjacent to the magnet 32 ​​and the bearing 22, with the rotating shaft 13 inserted through it.

[0041] The preload spring 35 applies a constant preload to the bearing 22. By applying a constant preload to the bearing 22, the preload spring 35 absorbs fluctuations in load and expansion and contraction of the rotating shaft 13 due to temperature differences between the rotating shaft 13 and the base portion 21 during rotation, resulting in less fluctuation in the preload amount and a stable preload amount. Therefore, the preload spring 35 prevents high-speed rotation of the rotating shaft 13 and axial vibration of the rotating shaft 13, allowing for rotational drive at higher speeds compared to fixed-position preload, and preventing axial vibration.

[0042] The preload spring 35 applies preload to the bearings (especially ball bearings) 22 and 23, thereby maintaining low friction and high reliability in the rotational drive of the rotating shaft 13, and enabling stable drive.

[0043] Furthermore, it is desirable that the preload spring 35 be in contact with a firmly fixed component and receive preload from that component. The annular receiving portion 37 is a press-fit ring and is fixed to the rotating shaft 13 by being press-fitted onto the outer circumference of the rotating shaft 13.

[0044] The annular receiving portion 37 receives one end of the preload spring 35, which abuts the bearing 22 at one end, thereby preventing direct impact from being applied to the magnet 32, which is an adhesive fixing component. This prevents unnecessary force from being applied to the magnet 32, thereby improving its reliability.

[0045] In addition, since the preloading spring 35 is disposed inside the rotary reciprocating drive actuator 1, a stable preloading design can be ensured without being affected from the outside of the rotary reciprocating drive actuator 1.

[0046] Note that the preloading spring 35 may be changed to a cylindrical coil spring formed by winding a round steel wire in a spiral shape, or a wave spring having a shape in which a plate-shaped steel wire is wound in a spiral or annular shape and waves are added, as a spring having a low height as a spring in the expansion and contraction direction, that is, in the spring height direction.

[0047] For example, as the preloading spring 350 having an axial length shorter than the axial length L1 of the cylindrical coil spring as the preloading spring 35, the preloading spring 350 as the wave spring shown in FIG. 10 may be used.

[0048] In the preloading spring 350 which is a wave spring, the axial length L2 in the expansion and contraction direction is shorter than the length L1 of the cylindrical coil spring, and the expansion and contraction length is short.

[0049] When the length L0 of the wall portion 211 and the annular receiving portion 37 corresponds to conditions such as a range where L2 < L0 < L1, the preloading spring 350 can be stacked in the direction of the length L2 in a plurality of layers to change its expansion and contraction length.

[0050] As described above, the preloading springs 35 and 350 can be appropriately changed according to the installation location or the preloading target to adjust the preloading force, prevent suitable high-speed rotation and axial vibration, and stably drive.

[0051] FIG. 11 is an enlarged perspective view of the front end portion of the rotary reciprocating drive actuator, FIG. 12 is a perspective view showing the inside of the top cover with the sensor substrate 72 removed in FIG. 11, FIG. 13 is a cross-sectional view taken along the arrow C-C line in FIG. 11, and FIG. 14 is an exploded perspective view of the drive unit.

[0052] <Drive unit 4> The drive unit 4 shown in Figures 2 to 6 and Figures 11 to 14 is provided at one of the axially separated ends of the base portion 21 and constitutes part of the fixed body 20. The drive unit 4, together with the magnet 32, constitutes the drive unit 30 and moves the movable body 10. The drive unit 4 has a bottom cover (connecting surface portion) 50, a core assembly 40, and a top cover 60. The drive unit 4 is formed, for example, as a rectangular parallelepiped with a square shape when viewed from the front.

[0053] <Core assembly 40> The core assembly 40 shown in Figures 3, 4 and 14 includes coils 44 and 45, bobbins 46 and 47 around which the coils 44 and 45 are wound, a core body 400, and a rotational angle position holding part 48.

[0054] In this embodiment, the core assembly 40 is formed in the shape of a rectangular frame block (more specifically, a rectangular parallelepiped) with magnetic poles 410a and 410b arranged on its inner side. The core assembly 40 is formed so that its outer peripheral portion surrounds the magnetic poles 410a and 410b located on the inner side of the outer peripheral portion. For example, in the wall portion 211 of the base portion 21, the core assembly 40 folds back and extends from each of the magnetic poles 410a and 410b that sandwich the magnet 32 ​​within the rectangular region of the wall surface as viewed from the axial direction, forming a single magnetic path that surrounds the magnetic poles 410a and 410b.

[0055] <Core body 400> The core body 400 constitutes a magnetic circuit having a magnetic path arranged to surround the magnet 32. The core body 400 has a first core 41 which is an integrated structure including a plurality of magnetic poles 410a, 410b and a C-shaped magnetic path section (connecting edge section 412 and side edge section 413), a second core 42 which is arranged to span between the side edge sections 413 of the first core 41, and a frame-shaped third core 43. The core body 400 is integrated by magnetically coupling the first to third cores.

[0056] The first core 41 to the third core 43 pass the magnetic flux generated when coils 44 and 45 are energized through multiple magnetic poles 410a and 410b. The first core 41 to the third core 43 are laminated cores formed by laminating electromagnetic steel sheets (laminated members), such as silicon steel sheets. By making the core body 400 a laminated structure, the first core 41 to the third core 43 can be constructed at low cost and have complex shapes.

[0057] <1st Core 41> In the first core 41, a connecting edge portion 412 is connected to the base ends of a plurality of rod-shaped bodies 411 (411a, 411b), each having opposing magnetic poles at its tip, and extending perpendicularly to the direction of their extension. Both ends of this connecting edge portion 412 have side edges 413a and 413b protruding perpendicularly from them. The connecting edge portion 412 is provided with a complementary pole portion 414 that extends between the rod-shaped bodies 411a and 411b and parallel to them.

[0058] The rod-shaped body 411 (411a, 411b), connecting edge portion 412, side edge portion 413 (413a, 413b), and complementary pole portion 414 are integrally structured, and the first core 41 has a comb-tooth shape.

[0059] The rod-shaped bodies 411a and 411b each have magnetic poles on the side of their tip, and bobbins 46 and 47 are externally fitted to the base end of the outer circumference of the rod-shaped bodies 411a and 411b. As a result, the coils 44 and 45 are arranged to wind around the rod-shaped bodies 411a and 411b.

[0060] When coils 44 and 45 are energized, the magnetic poles at the tips of the rod-shaped bodies 411a and 411b develop polarity corresponding to the direction of current flow. The magnetic poles are positioned opposite the magnet 32, and each magnetic pole has a curved shape that follows the outer surface of the magnet 32. These curved shapes are positioned, for example, opposite each other in a direction perpendicular to the extending direction of the rod-shaped bodies 411a and 411b.

[0061] The rod-shaped bodies 411a and 411b have external dimensions that allow, for example, bobbins 46 and 47 to be extrapolated from the tip side. This allows the bobbins 46 and 47 to be extrapolated from the tip side in the extending direction of the rod-shaped bodies 411a and 411b, that is, from the tips of the magnetic poles 410a and 410b, and positioned to surround them at the base end side of the rod-shaped bodies 411a and 411b. The extrapolated bobbins 46 and 47 are each positioned between the side portion 413 and the complementary pole portion 414.

[0062] The connecting edge portion 412 constitutes one side of the rectangular core body 400, is connected to the base ends of the rod-shaped bodies 411a and 411b, and is arranged to extend in a direction perpendicular to the parallel direction of the rod-shaped bodies 411a and 411b.

[0063] The connecting edge portion 412 mainly connects the base ends of the rod-shaped bodies 411a and 411b to the side edge portions 413a and 413b. Preferably, the side edge portions 413a and 413b are in close contact with both ends of the second core 42, but here they are arranged so that there is a gap between each of the side edge portions 413a and 413b and each of the ends of the second core 42. The connecting edge portion 412 and the side edges 413a and 413b are arranged together with the second core 42 so as to be stacked in close contact with the third core 43 in the axial direction.

[0064] The complementary pole portion 414 is positioned opposite the rotational angle position holding portion 48, and when the magnet 32 ​​attracts the rotational angle position holding portion 48, it attracts the other pole of the magnet 32, reinforcing the attractive state with the rotational angle position holding portion 48.

[0065] Specifically, the complementary pole portion 414 is made of a magnetic material and is arranged, for example, together with the magnetic poles 410a, 410b and the rotational angle position holding portion 48 to surround the magnet 32 ​​on all four sides. The complementary pole 414 generates a magnetic attraction force with the magnet 32 ​​(more specifically, pole 32b), causing the magnet 32 ​​to move pole 32b, which is different from pole 32a that is attracted to the rotational angle position holding part 48, to an opposing position. Through this action, the complementary pole 414 cancels out the radial load acting on the movable body 10 due to the magnetic attraction force in the rotational angle position holding part 48. Note that "canceling out the radial load" also includes "causing the radial load to be canceled out."

[0066] Furthermore, the interpole surface of the interpole portion 414 that faces the outer surface of the magnet 32 ​​is a curved surface corresponding to the shape of the outer surface of the magnet 32, and has a uniform gap across its entire surface. Since the interpole portion 414, together with the rotational angle position holding portion 48, is arranged within the core assembly 40 so as to surround the magnet 32, it is laid out in the smallest possible space, enabling the realization of a more compact rotary reciprocating drive actuator 1.

[0067] <2nd Core 42> The second core 42, together with the first core 41, forms a magnetic path that surrounds the magnetic poles at the tips of the rod-shaped bodies 411a and 411b from all sides. The second core 42 is formed in a prismatic shape and forms a magnetic path through which magnetic flux passes to the magnetic poles 410a and 410b when current is supplied to the coils 44 and 45.

[0068] The second core 42 has the same thickness (axial length) as the side edges 413a and 413b. The second core 42 is fixed to the bottom cover 50 and the top cover 60 in close contact with the third core 43 via fastening members 86 inserted into mounting holes (fastening holes) 402 similar to those provided at both ends of the connecting edge of the first core 41 (see Figure 13). The mounting holes 402 have the same diameter as the through holes 54 in the bottom cover 50 and are formed to extend parallel to the rotation axis 13. A rotational angle position holding part 48 is attached to the second core 42 at the center in the extending direction and at a part facing the magnet 32.

[0069] <3rd Core 43> The third core 43, together with the connecting edge portion 412 and the side edge portion 413 of the first core 41 and the second core 42, surrounds multiple magnetic poles and forms a magnetic path that connects multiple magnetic poles. The third core 43 has a rectangular frame plate shape and is attached in surface contact with the rectangular frame portion composed of both the first core 41 and the second core 42.

[0070] Specifically, the third core 43 faces the connecting edge 412 and both side edges 413a and 413b of the first core 41 in the direction of extension of the rotation axis 13, and makes surface contact with each other. In addition, the third core 43 is assembled to the first core 41 in a positioned manner, with the multiple magnetic poles of the rod-shaped bodies 411a and 411b of the first core 41 positioned around the rotation axis 13. Furthermore, the third core 43 faces the second core 42 in the direction of extension of the rotation axis 13 and makes surface contact with it.

[0071] As a result, the third core 43 is positioned around the rotation axis 13 so as to surround the magnetic poles of the rod-shaped bodies 411a and 411b and the coils 44 and 45, forming a seamless magnetic path around the rotation axis 13. The first to third cores 41 to 43 have surrounding portions that enclose the coils 44 and 45, and can form a flow of magnetic flux that passes from one magnetic pole through the first core 41 + third core 43, the third core 43, the third core 43 + second core 42, and the other magnetic pole of the third core 43 + first core 41. In addition, since the first to third cores 41 to 43 enclose the magnetic poles and the magnets 32 between the magnetic poles in an annular manner, contact with the coils 44 and 45 from the outside can be prevented.

[0072] In the assembled state of the drive unit 4, the rotating shaft 13 is inserted into the space surrounded by magnetic poles. A magnet 32 ​​attached to the rotating shaft 13 is also located in this space, and the magnetic poles of the magnet 32 ​​face each other at precise positions via an air gap G.

[0073] The magnet 32 ​​is a ring-shaped magnet with alternating south poles 32a and north poles 32b arranged in the circumferential direction. When the rotary reciprocating drive actuator 1 is assembled, the magnet 32 ​​is mounted on the circumferential surface of the rotating shaft 13 so as to be located in the space surrounded by the magnetic poles 410a and 410b of the core body 400. The magnet 32 ​​is fixed so as to surround the outer circumference of the rotating shaft 13. When current is supplied to the coils 44 and 45, the first core 41, second core 42 and third core 43, which include the rod-shaped bodies 411a and 411b, are energized, and polarity corresponding to the direction of current supply is generated in the magnetic poles 410a and 410b. As a result, magnetic force (attraction and repulsion) is generated between the magnetic poles 410a and 410b and the magnet 32.

[0074] In this embodiment, the magnet 32 ​​is magnetized with different polarities, with a plane along the axial direction of the rotation axis 13 as the boundary. That is, the magnet 32 ​​is a two-pole magnet magnetized so as to be equally divided into an S pole 32a and an N pole 32b. The number of magnetic poles of the magnet 32 ​​(two in this embodiment) is equal to the number of magnetic poles 410a and 410b of the core body 400. Note that the magnet 32 ​​may be magnetized with two or more poles depending on the amplitude during movement. In this case, the magnetic pole portion of the core body 400 is provided corresponding to the magnetic poles of the magnet 32.

[0075] <Magnet 32> The magnet 32 ​​switches polarity at the boundary portions 32c and 32d between the south pole 32a and the north pole 32b (hereinafter referred to as the "magnetic pole switching portion"). The magnetic pole switching portions 32c and 32d are formed in the shape of grooves extending through the axis on one end face of the magnet 32. When the magnet 32 ​​is held in the neutral position, the magnetic pole switching portions 32c and 32d face the magnetic poles 410a and 410b, respectively.

[0076] If the magnetic pole switching sections 32c and 32d are formed in a groove shape, the positional relationship of each component fixed to the rotating shaft 13 can be adjusted using these grooves as a reference during assembly or maintenance of the rotary reciprocating drive actuator 1. In particular, the position of the mirror section 12, the mounting position of the encoder of the angle sensor section 70, etc., can be precisely and appropriately defined in accordance with the positions of the magnetic pole switching sections 32c and 32d of the magnet 32. For example, by applying a jig to the groove in the axial direction and fitting a projection into the groove, the rotation of the rotating shaft 13 around its axis is restricted and immobilized, and this becomes the reference position for other components attached to the rotating shaft 13. In particular, precision is required for adjusting the angle of the mirror relative to the poles of the magnet 32, and this makes that possible.

[0077] In the neutral position, the magnetic pole switching sections 32c and 32d of the magnet 32 ​​face the magnetic poles 410a and 410b directly, allowing the drive unit 4 to generate maximum torque and stably drive the movable body 10.

[0078] Furthermore, by configuring the magnet 32 ​​as a two-pole magnet, it becomes easier to drive the movable object with high amplitude in cooperation with the core body 400, and the driving performance can be improved. In other words, the mirror part 12, which is the movable object, can be driven at a wide angle. In this embodiment, the case in which the magnet 32 ​​has a pair of magnetic pole switching parts 32c and 32d has been described, but it may have two or more pairs of magnetic pole switching parts.

[0079] <Coiled structure (coil and bobbin)> Coils 44 and 45 are wound around cylindrical bobbins 46 and 47. The coil body, consisting of coils 44 and 45 and bobbins 46 and 47, is extrapolated onto the rod-shaped bodies 411a and 411b of the first core 41, so that coils 44 and 45 are arranged to wind around the rod-shaped bodies 411a and 411b. In this way, coils 44 and 45 are positioned adjacent to the magnetic poles at the tips of the rod-shaped bodies 411a and 411b.

[0080] The winding direction of coils 44 and 45 is set such that, when current is applied, a suitable magnetic flux is generated from one of the multiple magnetic poles of the first core 41 toward the other.

[0081] Figure 15 is a perspective view of the coil, Figure 16 is an exploded view of the bobbin, and Figure 17 is a perspective view showing the coil wiring configuration in the coil.

[0082] Since the configuration of a coil body having a bobbin 46 around which coil 44 is wound and a coil body having a bobbin 47 around which coil 45 is wound are similar, we will describe the coil body having a bobbin 46 around which coil 44 is wound, and omit the description of the coil body having coil 45 and bobbin 47.

[0083] The coil body 49 has a bobbin portion 492 around which the coil 44 is wound, and a terminal support portion 494 that supports the terminal 496 and is provided integrally with the bobbin portion 492.

[0084] The bobbin portion 492 has a through hole through which the rod-shaped body 411 (411a, 411b) is inserted, and a terminal support portion 494 is provided protruding from the flange of the opening edge on one side of the bobbin portion 492.

[0085] Each terminal support portion 494 has a cylindrical shape, into which a terminal 496 is inserted and which is held in place.

[0086] The terminal 496 is L-shaped, with one side 4962 connecting to the end of the coil 44, the base end of the other side 4964 being inserted into and supported by the terminal support portion 494, and the tip end of the other side 4964 protruding outward from the terminal support portion 494.

[0087] The other side portion 4964 is connected to an external device that supplies power to the coil 44 or to the end of an adjacent coil. In this embodiment, the terminal 496 has one side portion 4962 extending parallel to the axial direction of the coil 44, and the other side portion 4964 extending perpendicular to the axial direction of the coil 44.

[0088] In the coil body 49, one side 4962 of the terminal 496 extends in the direction of the opening of the bobbin portion 492, while the other side 4964 extends in the direction of the flange of the bobbin portion 492.

[0089] At one side section 4962, the coil wires at both ends of the coil 44 are connected by a connection section H made of solder or the like.

[0090] Thus, the terminal 496 is L-shaped, with a coil winding connected to one side, the one-side portion 4962 (the connection portion H which is a fillet), and joined to the sensor substrate 72 at the other side 4964.

[0091] Since terminal 496 is L-shaped, the sensor board connection side and the coil connection side can be connected separately, and in particular, the work of forming the connection part (fillet) H for connecting the coil windings with solder can be performed easily without interference between the solder and the windings.

[0092] In other words, even if the work of connecting the sensor board 72 and the work of fixing the winding of the same terminal 496 are required, there will be no obstacles to the connection process with the board, such as solder adhering when conducting the winding. The connection between the sensor board 72 and terminal 496 can be positioned and contamination prevention can be carried out by arranging the sensor board 72 in the axial direction relative to the drive unit 4, and the optical sensor 76 can be easily positioned perpendicular to the axial direction.

[0093] <Rotation angle position holding part (magnetic position holding part) 48> The rotational angle position holding section 48 shown in Figures 2 to 4 is incorporated into the core assembly 40 so as to face the magnet 32 ​​via an air gap G when the rotary reciprocating drive actuator 1 is assembled. The rotational angle position holding section 48 is mounted, for example, on the second core 42 in a position where its magnetic poles face the magnet 32.

[0094] The rotational angle position holding unit 48 uses, for example, a magnet with its magnetic poles pointed towards the magnet 32 ​​to generate a magnetic attractive force between itself and the magnet 32, thereby attracting the magnet 32. In other words, the rotational angle position holding unit 48, together with the rod-shaped bodies 411a and 411b, forms a magnetic spring between itself and the magnet 32. Due to this magnetic spring, when the coils 44 and 45 are not energized (unpowered), the rotational angle position of the magnet 32, i.e., the rotational angle position of the rotation axis 13, is held in the neutral position.

[0095] At this time, the magnetic pole 32b (N pole shown in Figure 3), which is opposite to the magnetic pole 32a (S pole in Figure 3) of the magnet 32 ​​that attracts the rotational angle position holding part 48, attracts the complementary pole part 414 of the first core 41, which is a nearby magnetic material. As a result, the magnet 32, and thus the movable object, the mirror part 12, is more effectively held in the neutral position.

[0096] The neutral position is the reference position for the reciprocating rotation of the magnet 32, that is, the center position of the reciprocating rotation (oscillation), and is the position where the rotation angle is the same when rotating left and right around the axis during reciprocating rotation. When the magnet 32 ​​is held in the neutral position, the magnetic pole switching parts 32c and 32d of the magnet 32 ​​face the magnetic poles of the rod-shaped bodies 411a and 411b.

[0097] Furthermore, the mounting position of the mirror section 12 is adjusted based on the state in which the magnet 32 ​​is in the neutral position. The rotation angle position holding section 48 may be made of a magnetic material that generates a magnetic attraction force between itself and the magnet 32.

[0098] <Bottom cover 50 and top cover 60> The bottom cover 50 and top cover 60 shown in Figures 1, 2, 4-6, and 11-14 are preferably made of an electrically conductive material that is nonmagnetic and highly conductive, and function as an electromagnetic shield.

[0099] The bottom cover 50 and the top cover 60 are positioned on both sides of the core assembly 40 in the axial direction (thickness direction), respectively.

[0100] The bottom cover 50 and the top cover 60 can suppress the incidence of noise into the core assembly 40 and the emission of noise from the core body 400 to the outside.

[0101] The bottom cover 50 and top cover 60 are formed from a non-magnetic, electrically conductive, and highly thermally conductive material such as an aluminum alloy. Aluminum alloys offer a high degree of design flexibility, and the desired rigidity can be easily imparted to the bottom cover 50 and top cover 60. The bottom cover (connecting surface) 50 and the top cover (sensor placement area) 60 are fastened to the core assembly 40 by screws using fastening members 86 that sandwich it in the axial direction.

[0102] Therefore, if the bottom cover 50 and top cover 60 are made of aluminum alloy, the core assembly 40 is sandwiched between the bottom cover 50 and top cover 60, which are high-rigidity components, and fixed with the fastening member 86, resulting in a robust structure and improved reliability. Furthermore, the top cover 60 is suitable when it functions as a support that supports the other end of the rotating shaft 13.

[0103] Figure 18 is a front perspective view of the bottom cover. Figure 19 is a cross-sectional view taken along the line DD in Figure 11.

[0104] The bottom cover 50 is attached so as to overlap the outer surface of the wall portion 211. The bottom cover 50 is formed in a rectangular plate shape corresponding to the outer shape of the wall portion 211. The bottom cover 50 has a rectangular plate-shaped cover body 52, and an opening 53 is formed in the center of the cover body 52 through which the rotating shaft 13 is inserted. The opening 53 is positioned opposite the bearing 22, and the inner diameter of the opening 53 is larger than the outer diameter of the magnet 32. The bottom cover 50 can be positioned by inserting the rotating shaft 13 with the magnet 32 ​​mounted on it into the opening 53 and inserting the magnet 32 ​​into the core assembly 40.

[0105] A rotating shaft 13 is inserted through the opening 53, and a preload spring 35 is fitted onto the rotating shaft 13 (see Figure 2).

[0106] The cover body 52 of the bottom cover 50 is provided with a through hole 54, a through hole 55 for fixing to the base portion 21, a positioning hole 56, a position adjustment hole 57, and a core holding projection 58. A fastening member 86 that integrates the bottom cover 50 together with the core assembly 40 and the top cover 60 as a drive unit 4 is inserted through the through hole 54. The through hole 55 is formed in the mounting portion 522 that is attached to the wall portion 211. The mounting portion 522 constitutes the left and right sides of the cover body 52 that are spaced apart in a direction perpendicular to the axial direction, and includes the four corners of the cover body 52. ​​Through holes 55 are formed in each of these corners.

[0107] The opening 53, through holes 54 and 55, positioning hole 56, and position adjustment hole 57 are formed parallel to the axial direction of the rotation shaft 13. By inserting the fastening members 81 and 86 through holes 54 and 55, assembly to the base portion 21, assembly of the drive unit 4, and ultimately assembly of the rotary reciprocating drive actuator 1 can be performed in one axial direction.

[0108] As shown in Figure 13, the through hole 54 has a recessed counterbore 541 formed on the back surface of the cover body 52, and the counterbore 541 accommodates the head of a fastening member 86 such as a screw.

[0109] The core-holding projection 58 is provided on the cover body 52, protruding axially from positions that sandwich the opening 53, and engages with the core assembly 40 to position it when combined with the core assembly 40.

[0110] The core-holding projections 58 are inserted between the rod-shaped bodies 411a and 411b and the side portions 213a and 213b, preventing leakage of magnetic flux flowing between them. Furthermore, when the core assembly 40 is subjected to an impact, the core-holding projections 58 suppress displacement between the laminated cores constituting the core body 400, and between the laminated cores and the bottom cover 50, allowing them to be assembled together appropriately and improving impact resistance.

[0111] Furthermore, as shown in Figure 6, a positioning projection (positioning engagement portion, convex portion) 59 is provided on the back surface of the bottom cover 50. When the bottom cover 50 comes into contact with the base portion 21 with their centers aligned, the positioning projection 59 engages with a recess (positioned portion, concave portion) 218 ​​of the wall portion 211, thereby positioning it. Positioning of the bottom cover 50, and consequently the drive unit 4, is performed with reference to the center of the rotation axis 13, thereby suppressing variations in the performance of the drive portion.

[0112] The positioning projection 59 is, for example, an annular projection. On the other hand, the recess 218 of the wall portion 211 is an annular groove formed in the base portion 21 so as to surround the insertion hole 211a, as shown in Figures 5, 7, and 8. The positioning projection 59 engages with the recess 218 of the annular groove, thereby positioning both the wall portion 212 and the drive unit 4.

[0113] The top cover 60, together with the bottom cover 50, sandwiches the core assembly 40 from both axial sides and is integrally fixed with fastening members 86 to constitute the drive unit 4. In this embodiment, the top cover 60 functions as a sensor housing 65 that houses the optical sensor 76 that detects the rotation angle of the movable body 10, i.e., the rotation axis 13.

[0114] The top cover 60 has a top cover body 62 that covers the front end surface of the core assembly 40, and a sensor peripheral wall portion (peripheral wall portion) 64 that protrudes from the outer peripheral edge of the top cover body 62 toward the other end 132 in the axial direction and forms a concave sensor housing portion 65.

[0115] The top cover body 62 is a plate-like body that is square when viewed from the axial direction and has a concave portion 621 that opens toward the core assembly 40 side. The top cover body 62 is a square plate-like body, and the peripheral wall portion 64 is formed in the shape of a rectangular frame rising from the outer periphery of the top cover body 62.

[0116] The top cover body 62 of the top cover 60 is provided with a through hole 66. The through hole 66 is positioned in the top cover body 62 so as to be coaxial with the opening 53 of the bottom cover 50 and the bearings 22 and 23 of the base portion 21. A bush 39, through which a rotating shaft 13 is inserted, is fitted into the through hole 66 from the back side (one end 131 side). As a result, the bush 39 is attached to the top cover body 62 in a state where its direction of movement is restricted. The bush 39 and the rotating shaft 13 may be positioned to slide against each other, or they may be positioned with a gap between them.

[0117] The bush 39 prevents the impact on the rotating shaft 13 from being transmitted to the sensor component (encoder disk) on the other end 132. The bush 39 is attached to the top cover 60 such that the other end fits into the through hole 66 and one end is located within the concave portion 621.

[0118] In addition to the through hole 66, the top cover body 62 is provided with a bobbin engagement hole 67 that penetrates axially and engages with the bobbins 46 and 47.

[0119] The terminal support portion 494 of the coil body 49, which has bobbins 46 and 47, is fitted into the bobbin engagement hole 67. As a result, the terminal support portion 494 is inserted into the top cover body 62, and the other side portion 4964 protrudes from the terminal support portion 494.

[0120] The engagement between the bobbin engagement hole 67 and the terminal support portion 494 also functions as a positioning mechanism when assembling the core assembly 40 and the top cover 60.

[0121] <Angle sensor unit 70> An angle sensor unit 70 is attached to the top cover 60. The angle sensor unit 70 detects the rotation angle of the movable body 10, which includes the magnet 32 ​​and the rotating shaft 13. Based on the detection result of the angle sensor unit 70, the rotary reciprocating drive actuator 1 can control the rotation angle position and rotation speed of the movable body, specifically the mirror unit 12 which is the movable object, via the control unit.

[0122] The angle sensor unit 70 may be a magnetic or optical sensor. In this embodiment, the angle sensor unit 70 has a sensor substrate 72 and comprises an encoder disk 74 which is housed in a sensor housing 65 and constitutes the angle sensor unit 70, and an optical sensor (sensor) 76 which has a light source and a light receiving element.

[0123] The angle sensor unit 70 detects the rotation angle of the rotation shaft 13, and consequently the rotation angle of the mirror unit 12. The encoder disk 74 is fixed to the other end 132 of the rotation shaft 13 within the sensor housing unit 65 and rotates together with the magnet 32 ​​and the mirror unit 12. In other words, the rotation position of the encoder disk 74 is the same as the rotation position of the rotation shaft 13.

[0124] The optical sensor 76 emits light onto the encoder disk 74 and detects the rotational position (angle) of the encoder disk based on the reflected light. This allows the rotational positions of the magnet 32 ​​and the mirror section 12 to be detected.

[0125] The light sensor 76 is mounted on the sensor substrate 72, which is positioned to cover the peripheral wall portion 64 and close the sensor housing portion (sensor placement portion) 65.

[0126] The sensor board 72 is a board on which a light sensor 76 that detects the rotation angle of the rotation axis 13 is mounted. The sensor board 72 is positioned so as to cover the core assembly 40 from the other end 132 side, with the light sensor 76 facing the magnet 32 ​​side. The sensor substrate 72 is located in the center and has a mounting portion (encoder hub) for attaching the encoder disc and an opening 724 into which the rotating shaft 13 is inserted, as well as fastening holes 722 and through-holes 726.

[0127] The sensor board 72 is attached to the top cover 60 via a fastening member 84. The fastening holes provided in the top cover 60 are formed on the extension of the fastening holes 402 of the core assembly 40 and have the same axis and diameter as the fastening holes. In other words, the sensor substrate 72 is fixed to the core assembly 40 side via a fastening member 84 in a fastening hole of the same diameter that is continuous with the mounting hole (fastening hole) 402 of the core assembly 40.

[0128] In this manner, the sensor substrate 72, top cover 60, core assembly 40 (core body 400), and bottom cover 50 are fixed by fastening members 84 and 86 through axially continuous holes of the same diameter, such as fastening holes 722, mounting holes 402, and through holes 54.

[0129] The sensor board 72 has a circuit for detecting the rotational position (angle) of the encoder disk, as well as a circuit for supplying power to coils 44 and 45. The power supply circuit includes a circuit that connects one end of coils 44 and 45, and this circuit has a through-hole 726 into which the other side 4964 of a terminal support portion 494 provided on the bobbin having coils 44 and 45 is inserted and connected to the circuit.

[0130] By inserting the other ends 4964 into the through-holes 726, the coils 44 and 45 are connected at one end via the sensor board 72, and power supply input / output circuits are connected to the other ends of each coil.

[0131] As a result, by assembling the drive unit 4 and attaching the sensor board 72 to the top cover 60, a circuit for supplying power to the coils 44 and 45 can be configured, and unwanted objects such as foreign matter can be prevented from entering the sensing part of the sensor unit 70.

[0132] Furthermore, since the other side 4964 of the terminal support portion 494 in the coil body is directly connected to the sensor board 72, the sensor portion and the terminals that drive the actuator (motor portion) can be integrated and wired together on a single board, the sensor board 72. In other words, the circuit board used in the rotary reciprocating drive actuator 1 can be used to implement both the sensor circuit and the actuator drive circuit, allowing for the sharing of the board and unifying the connectors used when connecting the actuator itself to external devices.

[0133] Next, the operation of the rotary reciprocating actuator 1 will be explained using Figures 3 and 20. Figure 20 is a diagram illustrating the operation of the magnetic circuit of the rotary reciprocating actuator 1.

[0134] The magnetic poles 410a and 410b of the two rod-shaped bodies 411a and 411b of the core body 400 of the core assembly 40 are arranged so as to sandwich the magnet 32 ​​with an air gap G between them. When the coils 44 and 45 are not energized, the magnet 32 ​​is held in the neutral position by the magnetic attraction force between it and the rotation angle position holding part 48, as shown in Figure 3.

[0135] In this neutral position, one of the S pole 32a and N pole 32b of the magnet 32 ​​(S pole 32a in Figure 20) is attracted to the rotational angle position holding part 48 (see magnetic spring torque FM in Figure 20). At this time, the magnetic pole switching parts 32c and 32d face the center positions of the magnetic poles 410a and 410b of the core body 400. In addition, the complementary pole part 414 attracts the other of the S pole 32a and N pole 32b of the magnet 32 ​​(N pole 32b in Figure 20). As a result, the magnet 32 ​​moves to the neutral position more effectively.

[0136] When current is applied to coils 44 and 45, the core body 400 is energized, and the magnetic poles 410a and 410b acquire polarity corresponding to the direction of current application. For example, as shown in Figure 20, when current is applied to coils 44 and 45, a magnetic flux is generated inside the core body 400, and magnetic pole 410a becomes the north pole and magnetic pole 410b becomes the south pole.

[0137] As a result, the magnetic pole 410a, which is magnetized to the north, attracts the south pole 32a of the magnet 32, and the magnetic pole 410b, which is magnetized to the south, attracts the north pole 32b of the magnet 32. Then, a torque in the F direction is generated in the magnet 32 ​​around the axis of the rotating shaft 13, and the magnet 32 ​​rotates in the F direction. Consequently, the rotating shaft 13 also rotates in the F direction, and the mirror part 12 fixed to the rotating shaft 13 also rotates in the F direction.

[0138] Next, when current is applied to coils 44 and 45 in the reverse direction, the flow of magnetic flux generated inside the core body 400 becomes opposite to the direction shown in Figure 20, and magnetic pole 410a becomes the south pole and magnetic pole 410b becomes the north pole. The magnetic pole 410a, which has been magnetized to the south pole, attracts the north pole 32b of the magnet 32, and the magnetic pole 410b, which has been magnetized to the north pole, attracts the south pole 32a of the magnet 32. Then, a torque -F is generated in the magnet 32 ​​around the axis of the rotation shaft 13 in the opposite direction to the F direction, and the magnet 32 ​​rotates in the -F direction. Consequently, the rotation shaft 13 also rotates, and the mirror part 12 fixed to the rotation shaft 13 also rotates in the opposite direction to the direction shown in Figure 20. The rotary reciprocating actuator 1 rotates and reciprocates the mirror section 12 by repeating the above operations.

[0139] In practice, the rotary reciprocating actuator 1 is driven by an AC wave input to coils 44 and 45 from a power supply unit (corresponding, for example, the drive signal supply unit 103 in Figure 32). In other words, the direction of current flow in coils 44 and 45 is periodically switched. When the direction of current flow is switched, the magnetic attractive force between the rotational angle position holding unit 48 and the magnet 32, that is, the restoring force of the magnetic spring (magnetic spring torque FM and the torque in the opposite direction, "-FM", shown in Figure 20), biases the magnet 32 ​​to return to the neutral position. As a result, the movable body 10 is subjected to alternating torques in the F direction and the opposite direction (-F direction) around its axis. This causes the movable body 10 to rotate and reciprocate.

[0140] The driving principle of the rotary reciprocating actuator 1 is briefly described below. In the rotary reciprocating actuator 1 of this embodiment, the moment of inertia of the movable body (movable body 10) is J[kg·m 2 ], the torsional spring constant of the magnetic spring (magnetic poles 410a, 410b, rotational angle position holding part 48 and magnet 32) is K sp When the value is [N·m / rad], the resonant frequency F of the movable body relative to the fixed body (fixed body 20) is calculated by equation (1). r It vibrates (reciprocates) at [Hz].

[0141]

number

[0142] Since the movable body constitutes the mass portion in the spring-mass vibration model, the resonant frequency F of the movable body is set to the coils 44 and 45. r When an AC wave with a frequency equal to F is input, the movable body enters a resonant state. That is, the resonant frequency F of the movable body is input to coils 44 and 45 from the power supply unit. r By inputting an AC wave with approximately the same frequency, the moving body can be vibrated efficiently.

[0143] The equations of motion and circuit equations illustrating the driving principle of the rotary reciprocating actuator 1 are shown below. The rotary reciprocating 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] In other words, the moment of inertia J [kg·m] of the movable body in the rotary reciprocating actuator 1. 2, rotational 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 appropriately changed within the range that satisfies Equation (2). Also, voltage e(t) [V], resistance R [Ω], inductance L [H], back electromotive force constant K e [V / (rad / s)] can be appropriately changed within the range that satisfies Equation (3).

[0147] In this way, when the reciprocating rotary actuator 1 energizes the coil with an alternating current wave corresponding to the resonance frequency F determined by the moment of inertia J of the movable body and the spring constant K of the magnetic spring sp a large vibration output with high efficiency can be obtained. r

[0148] <Modification Example 1> FIG. 21 is a longitudinal sectional view showing Modification Example 1 of the reciprocating rotary actuator, and FIG. 22 is an exploded perspective view of Modification Example 1 of the reciprocating rotary actuator.

[0149] In the reciprocating rotary actuator 1A of Modification Example 1, compared with the reciprocating rotary actuator 1, the directions of the bearings 22 and 23 attached to the base portion 21A, and the positions of the preloading springs 35, the stopper portion 15A, and the stopping portion 14 are different, and other configurations are the same. Therefore, the same names with the same functions are denoted by the same reference numerals and the description thereof is omitted, and only the different points will be described.

[0150] In the reciprocating rotary actuator 1A, the movable body 10A is attached to the base portion 21A to form the main body unit A, and the reciprocating rotary actuator 1A has the drive unit 4 at the wall portion 211 which is one end of the main body unit 2.

[0151] The reciprocating rotary actuator 1A arranges the preloading spring 35 between the bearing 22 and the mirror holder 122 compared with the reciprocating rotary actuator 1.

[0152] The base portion 21A has a pair of wall portions 211A and 212A that rise from both ends of the bottom portion 213, which are spaced apart in the extending direction. Bearings 22 and 23, with flanges positioned axially inward, are positioned in the center of each of these wall portions. For example, bearings 22 and 23 are press-fitted into the through holes 211Aa and 212Aa from the axially inward side. The rotating shaft 13 is inserted through the bearings 22 and 23.

[0153] Furthermore, the stopper portion 15A is shorter than the stopper portion 15 and is attached to the base end of the rotating shaft 13 from the outside of the base portion 21A.

[0154] Furthermore, the stopper portion 14 is fitted into the fitting groove 133A on the inside of the wall portion 212 at the end of the rotating shaft 13A that passes through the wall portion 212A.

[0155] In this configuration, when a load is applied to the rotating shaft 13A from the axial outside of the stopper 15A, in other words, from the base end (one end 131) side of the rotating shaft 13A, the position of the rotating shaft 13A is maintained by the stopper 15A. Furthermore, even when the force of the preload spring 35 is applied, the position is maintained by the stopper 14, and the function of the preload spring 35 in the rotary reciprocating drive actuator 1 is similar, and the same effect can be obtained.

[0156] In other words, the movable body 10A has outward preload applied to both sides in the axial direction, and a preload spring 35 is positioned near the movable object. As a result, the preload spring 35 is positioned in the dead space of the rotating shaft 13 that is installed between the pair of wall sections (side wall sections) 211A and 212A of the base section 21A, which allows for a lower profile and smaller size compared to a configuration in which the preload spring 35 is positioned inside the drive unit 4.

[0157] <Modification 2> Figure 23 is an external perspective view of Modified Rotary Reciprocating Actuator 2, and Figure 24 is a perspective view of the main unit of Modified Rotary Reciprocating Actuator 2. Figure 25 is a front view showing the main components of the drive unit in Modified Rotary Reciprocating Actuator 2, and Figure 26 is a perspective view of Modified Rotary Reciprocating Actuator 2 as it is mounted on a product.

[0158] The rotary reciprocating drive actuator 1B shown in Figures 23 to 26 has the same function as the rotary reciprocating drive actuator 1, and also has a fixing hole 215 that serves as an actuator fixing part for fixing to the fixing base portion 800 of the product body.

[0159] The fixing holes 215 are provided, for example, in the wall portion 211B of the base portion 21B of the fixing body 20B, which has substantially the same function as the fixing body 20. The fixing holes 215 are formed in the flange-shaped side protrusions 2110 that extend in a direction perpendicular to the axial direction from the part of the wall portion 211B where the drive unit 4 is fixed. The fixing holes 215 may also be provided on one side of the side protrusions 2110.

[0160] The two side protrusions 2110 are arranged adjacent to each other on the left and right sides of the drive unit 4 when viewed from the front. The two side protrusions 2110 are positioned further outward than the two sides (the left and right outer sides when viewed from the front) of the mounting portion 522 that is attached to the wall portion 211B via the fastening member 81 on the bottom cover 50 of the drive unit 4.

[0161] On the back side of both protruding portions 2110, counterbore portions 2112 are provided around the fixing holes 215, so that the heads of the fastening members 87 do not protrude axially in the wall portion 211B.

[0162] The wall portion 211B has a positioning notch 217 and a positioning hole 216 that enable positioning when attaching the drive unit 4 to the product housing (e.g., the fixed base portion 800). The positioning notch 217 is provided on the outer edge of the wall portion 211B, for example, in the center of one of the two protruding edges 2110. In the wall portion 211B, the positioning hole 216 is formed at a position symmetrical to the positioning notch 217 with respect to the center.

[0163] When attaching the rotary reciprocating actuator 1B to the product's frame, the rotary reciprocating actuator 1B is fixed to a fixed base portion 800 provided on the frame side (for example, as part of the frame).

[0164] The fixed base portion 800 is configured as a U-shaped section having fixed wall portions 804 and 806 that are spaced apart and standing opposite each other. The rotary reciprocating drive actuator 1B is fixed to the fixed base portion 800 so that the drive unit 4 is located inside this U-shape. The rotary reciprocating drive actuator 1B is fixed with the side protrusions 2110 of the wall portion 211B in contact with the upper end surfaces of the fixed wall portions 804 and 806, with the vertical direction of the fixed base portion 800 and the axial direction parallel, and is fastened by a fastening member 87 that passes through a fixing hole 215. In addition to the fastening hole 807 into which the fastening member 87 is inserted, the upper end surfaces of the fixed wall portions 804 and 806 are provided with positioning protrusions 808 that are inserted into positioning holes 216.

[0165] When attaching the rotary reciprocating actuator 1B to the fixed base portion 800, the positions of both are adjusted by inserting a positioning projection 808 parallel to the axis into a positioning hole 216 parallel to the axis and rotating it around this projection. Further position adjustment is performed by inserting a rod or the like into the positioning notch 217, aligning the fixing hole 215 and the fastening hole 807, and then inserting the fastening member 87 through both to secure it.

[0166] Since the axial direction is the same as the axial direction of the bearing 22, which is determined by the position of the mirror portion 12, the rotary reciprocating drive actuator 1B can be accurately positioned and fixed to the fixed base portion 800.

[0167] Furthermore, a positioning notch 217, a positioning hole 216, and a fixing hole 215 are provided in the wall portion 211B that holds the mirror portion 12, and the wall portion 211B is fixed to the fixing base portion 800 using these. The wall portion 211B has an insertion hole for the bearing 22 of the rotating shaft 13 to which the mirror holder 122 is fixed, and also has an insertion hole 211a (coaxial with the insertion hole 211b) which is due to the position of the mirror, so positioning and fixing to the fixing base portion 80 is possible on the same machined surface as these, and fixing can be done with high precision.

[0168] If the actuator fixing part is provided on the drive unit 4 side, it can be fixed to the product body, i.e., the fixing base part 800, near the center of gravity of the rotary reciprocating drive actuator, thereby effectively suppressing external vibrations or shocks. The actuator fixing part may also be provided on the top cover of the drive unit 4.

[0169] <Variation 3> Figure 27 is an external perspective view of Modified Rotary Reciprocating Actuator 3, and Figure 28 is an external perspective view of the top cover of Modified Rotary Reciprocating Actuator 3. Figure 29 is a perspective view showing Modified Rotary Reciprocating Actuator 3 as it is mounted on a product.

[0170] The rotary reciprocating actuator 1C of the modified example 3 shown in Figures 27 and 28 differs from the rotary reciprocating actuator 1 only in the top cover 60C; the other components are the same. Therefore, components identical to those of the rotary reciprocating actuator 1 are denoted by the same reference numerals and their descriptions are omitted.

[0171] The rotary reciprocating actuator 1C shown in Figures 27 and 28 has a top cover 60C provided with fixing holes 625 that serve as actuator fixing parts.

[0172] The top cover 60C has a rectangular plate-shaped top cover body 62C, and both side protrusions 6210 are provided that extend in a direction perpendicular to the axial direction, similar to the wall portion 211B in the modified example 2. Fixing holes 625 extending parallel to the axial direction are provided in both side protrusions 6210. The top cover 60C, like the top cover 60, has a concave sensor housing portion 65 on its surface side and a recess formed on its back side, which have the same functions as the sensor housing portion 65 and recess of the top cover 60, respectively.

[0173] On the back side of the protruding edges 6210 on both sides of the top cover body 62C, a counterbore 6212 is provided, which is continuous with the fixing hole 625 and has a shape that cuts out around the fixing hole 625. This counterbore 6212 prevents the head of the fastening member 87 (see Figure 29), which is inserted into the drive unit 4C, from protruding axially in the wall portion 211B. The sensor housing portion 65 is provided with a through hole 66 and a bobbin engagement hole 67, and the sensor housing portion 65 is covered by the sensor substrate 72.

[0174] Furthermore, the top cover body 62C is provided with positioning holes 626 and positioning notches 627, which have the same function as the wall portion 211B. The positioning notches 627 are provided on the outer edge, for example, in the center of one side protruding portion 6210. In the top cover body 62C, the positioning holes 626 are formed at positions symmetrical to the positioning notches 627, with the center as the focal point.

[0175] In this rotary reciprocating actuator 1C, the fixing hole 625, which is the actuator fixing part, is provided in the top cover 60C of the drive unit 4C. As a result, the rotary reciprocating actuator 1C is fixed by inserting the fixing member 87 parallel to the axial direction into the fixing hole 625 and the fastening hole 807, respectively, into the pair of fixing wall parts 804 and 806 of the concave portion of the fixing base part 800, as shown in Figure 29, and tightening it. At this time, since the top cover 60C is fixed to the base portion 800, the drive unit 4C can be easily and accurately fixed between the fixing walls 804 and 806 without needing to insert it.

[0176] Furthermore, since the drive unit 4C is fixed to the fixed base 800, the rotary reciprocating drive actuator 1C is fixed to the fixed base 800 at a position close to its center of gravity, thus effectively dampening external vibrations and shocks.

[0177] The top cover 60C is provided with a positioning hole 626 and a positioning notch 627 that penetrate through it in the axial direction. By inserting the positioning projection 808 on the upper end surface of the fixed wall portion 806 into the positioning hole 626 and another positioning projection into the positioning notch 627, both can be positioned before fixing them together.

[0178] Furthermore, when attaching the rotary reciprocating actuator 1C to the fixed base 800, a positioning projection 808 parallel to the axis can be inserted into the positioning hole 626, which is parallel to the axis. By rotating the rotary reciprocating actuator 1C around this projection, the position between the rotary reciprocating actuator 1C and the fixed base 800 can be adjusted, and by inserting a rod or the like into the positioning notch 627, the position can be adjusted with even greater precision.

[0179] <Modification 4> Figure 30 is an external perspective view of the bottom cover of Modified Rotary Reciprocating Actuator 4, and Figure 31 is a perspective view showing Modified Rotary Reciprocating Actuator 4 as it is mounted on the product.

[0180] In the modified example 4, the rotary reciprocating actuator 1D has a fixing hole 525, which is the actuator fixing part, provided in the bottom cover 50D of the drive unit 4. Compared to the rotary reciprocating actuator 1, the rotary reciprocating actuator 1D differs only in the configuration of the bottom cover 50D; the other components are the same. Therefore, only the differences will be explained, and the same components will be given the same names and reference numerals and their explanations will be omitted.

[0181] As shown in Figure 30, the bottom cover 50D is similar to the bottom cover 50, and has a rectangular plate-shaped cover body 52 with an opening 53 in the center, and on both sides perpendicular to the axial direction, it has protruding side edges 5210, similar to the wall portion 211B in the modified example 2.

[0182] The protruding edges 5210 on both sides are portions that extend outward from the drive unit 4 and have fixing holes 525 that extend parallel to the axial direction. The bottom cover 50D, like the bottom cover 50, has positioning projections (not shown) protruding from its back surface. The positioning projections engage with recesses 218 in the wall portion 211 of the base portion 21 to position it.

[0183] As shown in Figure 31, the rotary reciprocating actuator 1D having this bottom cover 50D is fixed by inserting and tightening fastening members 87 parallel to the axial direction into the fixing holes 525 and fastening holes 807 in the pair of fixing walls 804 and 806 of the concave portion of the fixed base portion 800.

[0184] At this time, since the bottom cover 50D is fixed to the fixed base portion 800, the top cover 60 and core assembly 40 of the drive unit 4C can be positioned between the fixed wall portions 804 and 806 and fixed with good precision in a shortened axial position.

[0185] Furthermore, since the drive unit 4D is fixed to the fixed base 800, the rotary reciprocating drive actuator 1D is fixed to the fixed base 800 at a position close to its center of gravity, which allows for effective damping of external vibrations and shocks.

[0186] In particular, the rotary reciprocating actuator 1D is fixed to the fixed base 800 by a bottom cover 50D disposed between the core assembly 40 and the mirror section 12. As a result, it is fixed to the fixed base 800 at the center of gravity located between the core assembly 40 and the mirror section 12, enabling stable holding.

[0187] The bottom cover 50D is provided with a positioning hole 526 and a positioning notch 527 that penetrates axially. This allows a positioning projection 808 on the upper end surface of the fixed wall portion 806 to be inserted into the positioning hole 526, and another positioning projection 808 to be inserted into the positioning notch 527. In this way, both can be accurately positioned before fixing them together via the fastening hole 807 and the fixing hole 525.

[0188] Furthermore, when attaching the rotary reciprocating actuator 1C to the fixed base 800, the positioning projection 808, which is parallel to the axis, can be inserted into the positioning hole 216, which is parallel to the axis, and the positions of both can be adjusted by rotating them around this projection. In addition, a rod or the like can be inserted into the positioning notch 217 to further adjust the position with even greater precision.

[0189] Figure 32 is a block diagram showing the main components of a scanner system 100 using a rotary reciprocating actuator 1.

[0190] The scanner system 100 includes one of the rotary reciprocating actuators 1, 1A to 1D, and in addition to these rotary reciprocating actuators 1, 1A to 1D, it also has a laser light-emitting unit 101, a laser control unit 102, a drive signal supply unit 103, and a position control signal calculation unit 104.

[0191] The laser light-emitting unit 101 includes, for example, a laser diode (LD) that serves as a light source and a lens system for focusing the laser light output from this light source. The laser control unit 102 controls the laser light-emitting unit 101. The laser light emitted from the laser light-emitting unit 101 is incident on the mirror 121 of the rotary reciprocating actuator 1.

[0192] The position control signal calculation unit 104 generates and outputs a drive signal to control the rotation axis 13 (mirror 121) to the target angle position by referring to the angular position of the rotation axis 13 (mirror 121) acquired by the angle sensor unit 70 and the target angular position. For example, the position control signal calculation unit 104 generates a position control signal based on the acquired angular position of the rotation axis 13 (mirror 121) 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.

[0193] The drive signal supply unit 103 supplies drive signals to the coils 44 and 45 of the rotary reciprocating drive actuator 1 based on the position control signal, such that the angular position of the rotation axis 13 (mirror 121) becomes a desired angular position. As a result, the scanner system 100 can emit scanning light from the rotary reciprocating drive actuator 1 into a predetermined scanning area.

[0194] <Summary> As described above, the rotary reciprocating actuator 1 according to this embodiment has a main unit 2 having a movable body 10 and a base portion 21, and a drive unit 4 that can be assembled independently of the main unit 2. The rotary reciprocating actuator 1 is constructed by assembling the main unit 2 and the drive unit 4, which are assembled separately from each other. The drive unit 4 has a core assembly 40, a bottom cover (connecting surface portion) 50, and a top cover 60.

[0195] The movable body 10 has a shaft portion 13 to which a mirror portion (movable object) 12 is fixed at one end 131 and a magnet 32 ​​is fixed at the other end 132, and is capable of reciprocating rotation around the shaft. The base portion 21 is arranged to sandwich the mirror portion 12 and has a pair of wall portions 211 and 212 that rotatably support the shaft portion 13 via bearings 22 and 23. The base portion 21 rotatably supports the rotating shaft 13 with the pair of wall portions 211 and 212, with the other end 132 of the rotating shaft 13 protruding from one of the wall portions 211 and 212.

[0196] The core assembly 40 includes a core body 400, a coil body 49, and a magnet position holding part 48. The core body 400 has a plurality of magnetic poles 410a, 410b facing the outer circumference of the magnet 32, sandwiching the magnet 32. The coil body 49 has coils 44, 45 wound around the core body 400 that generate magnetic flux by energizing to interact with the magnet 32 ​​and cause the movable body 10 to reciprocate.

[0197] The magnet position holding part 48 generates a magnetic attractive force between itself and the magnet 32 ​​to define the reference position for reciprocating rotation. The bottom cover (connecting surface part) 50 is integrally provided on one end of the core assembly 40, and with the magnet 32 ​​inserted into the opening 53, the core assembly 40 is assembled to the wall part 211 on the other end 132 side.

[0198] According to the rotary reciprocating drive actuator 1 of this embodiment, the assembly of the main unit 2 and the drive unit 4 can be performed separately, improving ease of assembly. Furthermore, strength can be ensured even in sub-assembly. In this way, it is possible to shorten the assembly time while having a structure that ensures high assembly precision and mechanically stable operation.

[0199] Furthermore, the bottom cover 50 has an axis parallel to the axis of the opening 53 and a positioning projection (positioning engagement part) 59 that engages with a recess 218 in the wall portion 211 on the other end 132 side, so that they can be joined together reliably and accurately. In addition, the assembly of the bottom cover 50 and the base portion 21 can be automated.

[0200] Furthermore, the sensor substrate 72 is located outside the drive unit 30 (core body 400, magnet 32) and, together with the magnet 32, covers the area around the detection part (encoder disk) of the sensor component. This prevents contamination of the sensor housing 65 and, consequently, the air gap G between the magnet and the core body 400. In this way, the ingress of foreign matter into the air gap G is prevented, preventing malfunctions and allowing for optimal driving.

[0201] Furthermore, since the magnet 32 ​​is located inside the drive unit 4 of the rotary reciprocating actuator, no magnet is located on the outside, and the magnetic flux is not distributed to the outside (front side), reducing leakage magnetic flux to the front side, and allowing the unit to be installed even if there are magnetically sensitive products nearby.

[0202] Since the core assembly 40 of the drive unit 4 is a rectangular frame-shaped block, the core assembly 40 can be installed in a limited space, such as a rectangular area (viewed in the axial direction) of the wall surface of the wall portion 211 of the base portion 21, and a sufficient magnetic path length can be secured, enabling high-amplitude driving of the movable body 20.

[0203] Furthermore, when maintaining the angle sensor unit 70, simply removing the fastening member 84 exposes the sensor component, which is an expensive part, to the outside, allowing for easy repair or replacement in case of malfunction.

[0204] Furthermore, if the sensor unit is an optical sensor, light interference to the sensor housing 65 can be prevented without using a separate light-shielding member.

[0205] When fixing the drive unit 4 to the main unit 2, it is desirable to fix it at a position where the dimensions can be defined from the reference point of the rotating shaft 13. Furthermore, when fixing the rotary reciprocating drive actuator to the product housing with the shaft vertically positioned, the assembly and installation of the rotary reciprocating drive actuator can be performed by positioning and fixing it from a direction parallel to the shaft. This allows for more precise positioning and fixing with less dimensional adjustment than when assembling in a direction different from the shaft orientation.

[0206] Furthermore, as shown in Figures 4, 11, and 13, the drive unit 4 of the rotary reciprocating actuator 1 has through holes into which fastening members 86 for fastening the bottom cover 50, core assembly 40, and top cover 60 are inserted, and through holes into which fastening members 81 for fastening the top cover 60 and sensor substrate 72 are inserted, all of which are through holes extending parallel to the axial direction and sharing the same axis. In other words, the sensor substrate 72 is fastened using the same screw holes (through holes) used to fix the drive unit 4, eliminating the need for additional screw holes to fix the sensor substrate 72 and thus reducing costs.

[0207] A shock-absorbing bush 39 is positioned adjacent to the sensor component, such as the rotary encoder. This prevents the sensor component from being affected by shocks, even if the rotating shaft 13 vibrates due to disturbances such as shocks received by the rotary reciprocating drive actuator 1.

[0208] Furthermore, a gap (clearance) narrower than the air gaps G and G1 between the magnet 32 ​​and the core assembly 40 may be provided between the bush 39 and the outer circumference of the rotating shaft 13. In this case, sliding between the bush 39 and the rotating shaft 13 is eliminated, ensuring shock resistance. Alternatively, if the bush 39 and the rotating shaft 13 slide against each other, the bush 39 will reliably absorb the impact, preventing shock to the sensor part, dampening unwanted vibrations of the moving body, and reducing noise.

[0209] Furthermore, the movable object is the mirror section 12 (particularly the mirror 121) that reflects scanning light. This allows the rotary reciprocating actuator 1 to be used in the application of a scanner that performs optical scanning.

[0210] Furthermore, in this embodiment, the ring-shaped magnets 32 of the rotary reciprocating drive actuators 1, 1A to 1D have their magnetic pole switching sections 32c and 32d configured with U-shaped grooves formed on one end face 322, as shown in Figure 33, but they do not necessarily have to be configured with U-shaped grooves. The magnetic pole switching section can be configured in any way as long as it indicates the position where the magnetic poles of the magnet 32 ​​change. Modified examples of the magnet 32 ​​will be described with reference to Figures 33 to 37.

[0211] Figures 33 to 37 show modified examples 1 to 4 of the magnets in rotary reciprocating actuators 1, 1A to 1D. Figures 34 to 36, A and B respectively, show the front view and right side view of the modified magnets, and Figure 37 shows the core assembly of the rotary reciprocating actuator having modified example 4.

[0212] The magnets 320, 320A, and 320B shown in Figures 34 to 36 are formed on rings, each having an opening 321 through which the rotating shafts 13 and 13A are inserted. The magnet 320 shown in Figure 34 has projecting magnetic pole switching portions 32e and 32f integrally on the diameter portion of one end face 322.

[0213] The magnetic pole switching sections 32e and 32f allow the shape of the magnet 320 to determine the position where the magnetic poles of the magnet 320 switch.

[0214] Furthermore, the magnet 320A shown in Figure 35 has a magnetic pole switching section 32g on the end face 322 of its ring-shaped body, which has a V-shaped cross-section instead of a U-shaped cross-section.

[0215] The magnetic pole switching sections 32g and 32f allow the shape of the magnet 320A to determine the position where the magnetic poles of the magnet 320 switch.

[0216] Here, it is desirable that the assembly accuracy of the magnetic pole direction of the magnets 320 and 320A be balanced to match the angle reference of the mirror section 12, which is the movable object, and the angle reference of the angle sensor 76. If there is a deviation in each angle reference, the characteristics will change depending on the rotation angle of the rotation axis 13, which is a problem that will cause performance variations.

[0217] In contrast, in this embodiment, the magnetic pole switching sections 32c to 32h in magnets 32, 320, and 320A are formed in the shape of a U, protruding, V, etc., and magnets 32, 320, and 320A have a shape that is uneven in the direction of magnetization.

[0218] Therefore, using a positioning jig (not shown) having pins corresponding to U-shaped, protruding, V-shaped, etc., the rotary reciprocating drive actuator 1 can be assembled to other parts or assembled using these magnetic pole switching parts 32c, 32d, 32e, 32f, 32g, and 32h as references.

[0219] In other words, the relative positions of the components fixed to the rotating shaft 13 can be adjusted using the uneven surface as a reference during assembly or maintenance of the rotary reciprocating drive actuator 1. The angular accuracy of the mirror section 12, the angular reference of the angle sensor section 70, and the magnetic pole reference of the magnet 32 ​​can be easily aligned, enabling high-precision assembly to be easily achieved.

[0220] Furthermore, if the magnet 32 ​​is configured such that the irregularities are provided in the direction of magnetization, the influence on the opposing magnetic poles 410a, 410b and the rotational angle position holding part (magnetic spring) 48 on the outer surface is small, resulting in less influence on torque, and preventing variations in the magnetic attractive force characteristics of the rotational angle position holding part 48.

[0221] The magnet 320B shown in Figure 36 has a flat surface 328 which is shaped by cutting out a portion of the outer surface 326. The flat surface 328 is provided as part of the outer surface of one of the different magnetic poles of the magnet 320B.

[0222] For example, when a core assembly 40B having a magnet 320B is provided on a rotary reciprocating drive actuator 1, it is arranged such that the magnetic pole 32a facing the rotational angle position holding part 48 shown in Figure 37 has a flat surface 328 on the magnetic pole 32b opposite to it. This flat surface 328 faces the curved surface of the complementary pole part 414. Specifically, when the magnet 320B is in the reference position, the flat surface 328 is arranged such that the center of its circumferential (horizontal) length and the center of the complementary pole part 414 in the circumferential (horizontal) direction are located on a line passing through the center of the opening 321 (rotation axis 13, 13A) and perpendicular to the flat surface 328.

[0223] In magnet 320B, if, for example, the flat surface 328 is positioned on the side of the rotational angle position holding part 48 or the core (magnetic pole 410), the flow of the generated magnetic flux will be unbalanced because the flat surface is only a small part of magnet 320B. This could affect the magnetic circuit characteristics and potentially degrade performance.

[0224] In contrast, in this embodiment, the flat surface 328 of the magnet 320B is configured to be positioned on the opposite side of the rotational angle position holding part 48 and the rotation shaft 13 when it is not energized, for example, when it is in the reference position. This allows the flat surface 328 to generate magnetic attraction force with the complementary pole part 414 without affecting the rotational angle position holding part 48, that is, without causing an imbalance in torque generation.

[0225] Although the present invention has been specifically described above based on embodiments, the present invention is not limited to the above embodiments and can be modified without departing from its spirit.

[0226] For example, the embodiment described a case where the movable object is the mirror part 12, but the movable object is not limited to this. The movable object may be, for example, an imaging device such as a camera.

[0227] Furthermore, although the embodiment described the case in which the rotary reciprocating drive actuator 1 is driven resonantly, the present invention can also be applied to cases where it is driven non-resonantly.

[0228] Furthermore, the configuration of the drive unit 4 is not limited to that described in the embodiment. For example, the core has magnetic pole portions that are excited by current flowing through the coil and generate polarity, and when the rotating shaft is attached to the stationary body, the magnetic pole portions and the outer surface of the magnet should face each other with an air gap in between. Also, the coil should have a configuration that, when energized, preferably generates magnetic flux from one magnetic pole portion of the core toward the other.

[0229] Furthermore, although the rotational angle position holding part 48 provided on the fixed body 20 is attached to the second core 42, the configuration is not limited to this, and it may be provided on other components of the fixed body 20. In these cases, the rotational angle position holding part 48 may be housed in the second core 42.

[0230] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Industrial applicability]

[0231] The present invention is suitable for applications such as LiDAR devices and scanner systems. [Explanation of symbols]

[0232] 1, 1A, 1B, 1C, 1D Rotary reciprocating actuator 2 Main Unit 4, 4C, 4D drive units 10, 10A movable body 12 Mirror section 13, 13A Rotation axis 14. Stopper 15, 15A Stopper section 20 Fixed body 21, 21A, 21B Base parts 22, 23 Bearings 30 Driving part 32, 320, 320A, 320B Magnets 32a, 32b, 410a, 410b Magnetic poles 32c, 32d, 32e, 32f, 32g, 32h Magnetic pole switching parts 35, 350 Preloading springs 37 Annular receiving part 39 Bush 40, 40B Core assemblies 41 First core 42 Second core 43 Third core 44, 45 Coils 46, 47 Bobbins 48 Rotation angle position holding part 49 Coil body 50, 50D Bottom cover (connection surface part) 52 Cover body 53, 321 Openings 54, 55, 66 Through holes 56, 216, 526, 626 Positioning holes 57 Position adjustment hole 58 Core holding protrusion 59, 808 Positioning protrusions (positioning engagement parts) [[ID=5,1]]60, 60C Top covers<--0000897-->62, 62C Top cover bodies 64 Peripheral wall part 65 Sensor housing part 67 Bobbin engagement hole 70 Angle sensor part 72 Sensor substrate 74 Encoder disk (detected part)<--0000904-->76 Optical sensor (sensor) 81, 84, 86, 87 Fixing members 100 Laser system 101 Laser emitting part 102 Laser control part 103 Driving signal supply part 104 Position Control Signal Calculation Unit 121 Mirror 122 Mirror Holder 122a, 211a, 211b, 211Aa, 212a, 211Aa, 212Aa Through hole 131 One end 132 Other end 133, 133A fitting groove 211, 211A, 211B, 212, 212A Wall section 213, 213A, 213B bottom 215, 525, 625 fixed hole 217, 527, 627 Positioning notches 218 Recess (positioning area) 222, 232 Bearing body 224, 234 flange 322 End face 326 Outer surface 328 Flat surface 400 core units 411, 411a, 411b Rod-shaped body 412 Connecting edge 413, 413a, 413b Side edges (both sides) 414 Complementary electrode section 492 Bobbin section 494 Terminal support part 496 terminals 522 Mounting section 541, 2112, 6212 Counterbore section 621 Concave part 726 Through-hole 800 Fixed base 804, 806 Fixed wall section 807 Fastening hole 2110, 5210, 6210 Both side protrusions 4964 Other side 4962 One side

Claims

1. A main body unit having a movable body having a shaft portion to which a movable object is connected at one end and to which a magnet is fixed at the other end, and a base portion having a pair of wall portions arranged to sandwich the movable object, with the other end of the shaft portion protruding from one of the pair of wall portions, and the shaft portion being rotatably supported by the pair of wall portions, A drive unit comprising a core body having a plurality of magnetic poles facing each other on the outer circumference of the magnet so as to sandwich the magnet, a coil body wound around the core body, and generating power when the coil body is energized to reciprocately drive the movable body, Equipped with, The drive unit includes a core assembly having a magnet position holding section that generates a magnetic attractive force between the core body, the coil body, and the magnet to define the reference position of the reciprocating rotation, A connecting surface portion is integrally provided on one end side of the core assembly, and is attached to the one wall portion with the shaft portion inserted through the opening and the magnet positioned inside the core assembly, An angle sensor unit for detecting the rotation of the shaft portion is provided, and a sensor placement unit is provided on the opposite side of the connection surface portion in the axial direction from the core assembly, so as to cover the core assembly. The core assembly is held and fixed between the sensor placement portion and the connection surface portion. Rotary reciprocating actuator.

2. The number of poles in the aforementioned plurality of magnetic poles is two. The rotary reciprocating actuator according to claim 1.

3. The connecting surface and the wall portion are assembled via a fastening member that fastens both of them in a direction along the axial direction of the shaft portion. The rotary reciprocating actuator according to claim 1.

4. The connecting surface portion has a positioning engagement portion that engages with the engaged portion of the wall portion in the axial direction to position it. The rotary reciprocating actuator according to claim 1.

5. The positioning engagement portion and the engaged portion are coaxial with the shaft portion and the opening, and have an annular convex portion and an annular concave portion that engage with each other in the axial direction. The rotary reciprocating actuator according to claim 4.

6. The connecting surface portion has a core-holding projection that protrudes toward the core assembly and holds the core within the core assembly. The rotary reciprocating actuator according to claim 1.

7. The aforementioned movable object is a mirror that reflects scanning light. The rotary reciprocating actuator according to claim 1.

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