Rotary reciprocating actuator

Abstract

The invention provides a rotary reciprocating drive actuator which can drive a movable object with a high amplitude in a more stable state while achieving a reduction in thickness. This rotary reciprocating drive actuator is provided with: a movable body which has a shaft part to which a magnet is fixed on the outer periphery thereof, and which is capable of reciprocating rotation around the shaft part; and a unit main body that reciprocates and rotates the movable body by interaction with the magnet. The unit main body has: an iron core body having a pair of magnetic poles extending on the same straight line on both sides in the radial direction of the shaft section with respect to the magnet, and a magnetic circuit section surrounding the pair of magnetic poles and the magnet and connecting the pair of magnetic poles; a pair of coil bodies wound around the pair of magnetic poles and interacting with each other when energized; and a biasing part that is disposed in a recess formed in the magnetic circuit part at a position between the pair of magnetic poles in the circumferential direction of the shaft part, and that biases the movable body toward an initial position at which the movable body reciprocates.

Description

Technical Field

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

[0002] Conventionally, a rotary reciprocating drive actuator is used as an actuator used in scanners of multifunction machines, laser printers, etc. Specifically, the rotary reciprocating drive actuator reciprocates a reflection mirror of the scanner to change the reflection angle of laser light to achieve optical scanning of an object.

[0003] As such a device using a rotary reciprocating drive actuator as a current motor, there are known various types of devices, such as a movable magnet type in which a magnet is provided on the movable part side as shown in Patent Document 1, a movable coil type in which a coil is provided on the reflective mirror side, and other types.

[0004] Patent document 1 is a beam scanner of a movable magnet type, in which a magnet is provided on the side of a reflector and is movable together with the reflector. In patent document 1, a rotating shaft with a reflector is provided between a pair of bearing walls arranged opposite to each other, four permanent magnets are provided on the rotating shaft in a manner magnetized in the radial direction of the rotating shaft, and an iron core having magnetic poles around which a coil is wound is provided in a manner sandwiching the rotating shaft.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent No. 4727509 Summary of the invention

[0008] Problems to be solved by the invention

[0009] However, compared with the movable coil type, the movable magnet type structure such as cited in Reference 1 is less likely to have adverse effects on the surface state of the reflector, the connection state of the reflector to the rotation axis, the shape of the reflector including warping, etc. due to the heat generated by the coil during driving.

[0010] In contrast, in the device disclosed in Patent Document 1, since the magnet is disposed on the reflector side, the heat generated by the coil does not affect the reflector. However, since the rotating shaft has four permanent magnets, it is difficult to achieve miniaturization and thickness reduction.

[0011] In recent years, in addition to being configured as a cantilever-type structure for supporting a reflector according to the size of a miniaturized scanner product, a rotary reciprocating drive actuator for a scanner is also expected to be thinner (miniaturized) in the structure of a housing in which a reflector is arranged between walls to rotatably support the reflector. Thus, the rotary reciprocating drive actuator can be configured in a narrow space to save space.

[0012] The present invention has been made in consideration of the above points, and provides a rotary reciprocating drive actuator that can be reduced in thickness and can drive a movable object with a high amplitude in a more stable state.

[0013] Solutions to Solve Problems

[0014] One embodiment of the rotary reciprocating drive actuator of the present invention comprises:

[0015] a movable body having a shaft portion having a magnet fixed to an outer periphery thereof and capable of reciprocating rotation about the shaft portion; and

[0016] a unit body which causes the movable body to reciprocate by interacting with the magnet,

[0017] The unit body has:

[0018] An iron core body having a pair of magnetic poles and a magnetic path portion, the pair of magnetic poles extending on the same straight line on both sides of the radial direction of the shaft portion relative to the magnet, and the magnetic path portion surrounding the pair of magnetic poles and the magnet and connecting the pair of magnetic poles;

[0019] a pair of coil bodies, which are wound around the pair of magnetic poles and generate the interaction by supplying electricity; and

[0020] The urging portion is disposed in a recessed portion formed in the magnetic circuit portion at a position between the pair of magnetic poles in a circumferential direction of the shaft portion and urges the movable body toward an initial position of reciprocating rotation.

[0021] Effects of the Invention

[0022] According to the present invention, a movable object can be driven with a high amplitude in a more stable state while achieving a reduction in thickness. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is an external perspective view of a scanning device having the rotary reciprocating drive actuator according to the first embodiment with part thereof removed.

[0024] Figure 2 This is an exploded perspective view of a scanning device having the rotary reciprocating drive actuator.

[0025] Figure 3 It is a perspective view of a rotary reciprocating drive actuator.

[0026] Figure 4 It is a perspective view showing the bottom cover and the top cover of the rotary reciprocating drive actuator.

[0027] Figure 5 yes Figure 3 Section view along line AA.

[0028] Figure 6 This is an exploded perspective view showing a state in which a bearing cover portion is removed from a drive unit of a rotary reciprocating drive actuator.

[0029] Figure 7 Viewed from the shaft end Figure 6 Diagram of the magnetic circuit structure of the drive unit.

[0030] Figure 8 It is an exploded perspective view of the iron core body.

[0031] Fig. 9 yes Figure 7 An enlarged view of the angular position maintaining portion is shown.

[0032] Fig. 10A 2 is a diagram showing a state where the angle position holding portion is installed in the recessed portion. Fig. 10B It is a figure which shows the state which removed the angle position holding part from the recessed part.

[0033] Fig.11 It is a diagram for explaining Modification 1 of the angular position holding unit.

[0034] Fig. 12A 2 is a diagram showing a preload imparting portion of a rotary reciprocating drive actuator. Fig. 12B 2 is a diagram showing a first modification of the preload imparting portion. Fig. 12C It is a diagram showing a second modification of the preload applying portion.

[0035] Fig.13 It is a diagram showing a magnetic circuit structure of an electromagnetic drive unit based on a rotary reciprocating drive actuator.

[0036] Fig.14 It is a figure for demonstrating the assembly method of the iron core body.

[0037] Fig.15 This is a diagram for explaining a method of installing a rotary reciprocating drive actuator.

[0038] Fig.16 This is a perspective view of the appearance of a scanning device having a rotary reciprocating drive actuator according to the second embodiment.

[0039] Fig.17 This is an exploded perspective view of a scanning device having a rotary reciprocating drive actuator according to a second embodiment.

[0040] Fig.18 It is a diagram showing a first modification of the bearing.

[0041] Fig.19 This is a perspective view of the appearance of a scanning device having a rotary reciprocating drive actuator according to a third embodiment.

[0042] Fig. 20This is an exploded perspective view of a scanning device having a rotary reciprocating drive actuator according to a third embodiment.

[0043] Fig.21 FIG. 1 is a diagram showing a main part configuration of a scanner system using a rotary reciprocating drive actuator. DETAILED DESCRIPTION

[0044] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0045] Figure 1 FIG. 1 is a perspective view of the appearance of the rotary reciprocating drive actuator according to Embodiment 1 with a portion removed. Figure 2 1 is an exploded perspective view of a scanning device having the rotary reciprocating drive actuator. Figure 3 is a perspective view of a rotary reciprocating drive actuator, Figure 4 is a perspective view showing the bottom cover and the top cover of the rotary reciprocating drive actuator, Figure 5 yes Figure 3 Section view along line AA.

[0046] Figure 1 as well as Figure 2 The rotary reciprocating drive actuator 1 shown is used in, for example, a laser radar (LiDAR: Laser Imaging Detection and Ranging) device. In addition, the rotary reciprocating drive actuator 1 can also be applied to optical scanning devices such as multifunction machines and laser beam printers.

[0047] Figure 1 The illustrated rotary reciprocating drive actuator 1 roughly includes: a drive unit 2 ; a mirror portion 3 rotatably supported by the drive unit 2 ; and an angle detection unit 70 that detects a rotational angle position of the mirror portion 3 .

[0048] <Mirror section 3>

[0049] The reflector unit 3 is a movable object in the rotary reciprocating drive actuator 1, and is connected to the rotating shaft 24, and is connected to the drive unit 2 via the rotating shaft 24. The reflector unit 3 reciprocates around the rotating shaft 24. The reflector unit 3 is formed by, for example, pasting the back side of the reflector 34 on one side of the reflector bracket 32. One end of the rotating shaft 24 is fixedly mounted on the reflector bracket 32, and the reflector 34 is held on the back side of the reflector 34. The reflector unit 3 is supported by the rotating shaft 24 in a cantilever manner so as to be rotatable around the axis, but is not limited to this structure.

[0050] In addition, a movable magnet (hereinafter referred to as "magnet") 36 is fixedly mounted on the portion of the rotating shaft 24 located in the driving unit 2. The magnet 36 constitutes an electromagnetic driving unit in the driving unit 2 together with the unit body 4 including the coils 461, 462, the iron core body, etc., and the reciprocating rotation drive is performed by the magnetic flux generated by the electromagnetic driving unit.

[0051] <Driver Unit 2>

[0052] like Figure 1 to Figure 5 As shown, the driving unit 2 includes: a unit movable body 20 having a rotating shaft 24 and a magnet 36 ; and a unit main body 4 that drives the unit movable body 20 to reciprocate and rotate.

[0053] The driving unit 2 supports the reflector part 3 by using the rotating shaft 24 protruding from the unit body 4 of the horizontally long rectangular parallelepiped shape, and drives the reflector part 3 to reciprocate and rotate via the rotating shaft 24. The driving unit 2 is used by fixing the unit body 4 to a bracket 80 used as a device housing or fixed to the device housing by using a fastening member 9 or the like. The bracket 80 has an opening for the rotating shaft 24 to be inserted, and the opening can also be a size that can insert the reflector part 3. In addition, the unit body 4 can be any shape such as a column, or a rectangular parallelepiped shape. In the present embodiment, the unit body 4 is a cube, so the configuration space can be reduced, and the space-saving configuration can be set by the corresponding cubic gap or the like. In addition, in the driving unit 2, the rotating shaft 24 is supported to be reciprocally rotatable in a state where the unit body 4 is inserted and the two ends protrude from the unit body 4. In addition, the unit movable body 20 constitutes the movable body of the rotary reciprocating drive actuator 1 together with the reflector part 3.

[0054] <Unit body 4>

[0055] like Figure 2 As shown, the unit body 4 is composed of each part of the drive unit 2 except the rotating shaft 24 and the magnet 36. The unit body 4 has: an iron core assembly 40, which accommodates the magnet 36 inside and allows the rotating shaft 24 to be inserted; and a first shaft support body 50 and a second shaft support body 60, which respectively support the inserted rotating shaft 24. In addition, for convenience, the first shaft support body 50 is also referred to as the bottom cover 50, and the second shaft support body 60 is also referred to as the top cover 60 for explanation.

[0056] The unit body 4 is formed by sandwiching the core assembly 40 from both sides of the extending direction of the rotating shaft 24 with the bottom cover 50 and the top cover 60 and fixing the bottom cover 50 and the top cover 60 to the core assembly 40. The unit body 4 forms a fixed body of the rotary reciprocating drive actuator 1.

[0057] In the unit body 4, the bottom cover 50, the core assembly 40, and the top cover 60 are fixed as a whole by the fastening member 91. In the unit body 4, the end surfaces of both sides of the extending direction of the rotating shaft 24 of the rectangular parallelepiped core assembly 40 are fully covered by the bottom cover 50 and the top cover 60. The unit body 4 prevents foreign matter from entering the core assembly 40 from the outside by the bottom cover 50 and the top cover 60.

[0058] <Core Assembly 40>

[0059] Figure 6 is an exploded perspective view showing a state where the bearing cover portion is removed from the rotary reciprocating drive actuator drive unit. Figure 7 It means when viewed from the shaft end. Figure 6 Diagram of the magnetic circuit structure of the drive unit. Figure 8 It is an exploded perspective view of the iron core body.

[0060] The core assembly 40 includes a core body K provided with coils 461 and 462 and an angle position holding unit (rotation angle position holding unit) 48. In the core assembly 40, the core body K is excited by energizing the coils 461 and 462, and forms a magnetic circuit together with the magnet 36.

[0061] In the present embodiment, the core assembly 40 is formed in a rectangular shape with the magnetic poles 412 and 414 arranged inside.

[0062] <Core K>

[0063] The core body K forms a magnetic path through which magnetic flux flows, is excited by supplying electricity to the coils 461 and 462 , and drives the magnet 36 to reciprocate and rotate due to electromagnetic action with the magnet 36 .

[0064] Figure 8 It is an exploded perspective view of the iron core body.

[0065] The core body K is a structure formed by combining multiple split bodies, namely multiple cores (here, three split bodies, namely first to third cores) 42 to 44. The multiple split bodies 42 to 44 are combined in the axial direction of the rotating shaft 24 so as to abut against each other entirely on surfaces perpendicular to the axial direction.

[0066] The core body K forms the overall outer shape of the core assembly 40 and has a rectangular parallelepiped shape.

[0067] The core body K includes a first core 42 and second and third cores 43 and 44 connected to the first core 42. The first, second and third cores 43 and 44 are magnetic bodies and pass magnetic flux generated when the coils 461 and 462 are energized through the plurality of magnetic poles 412 and 414.

[0068] The first core 42, the second core 43, and the third core 44 are laminated cores formed by laminating electromagnetic steel plates (laminated components) such as silicon steel plates. The laminated structure of the first core 42, the second core 43, and the third core 44 can be formed into a low-cost and complex shape.

[0069] The first core 42, the second core 43, and the third core 44 have positioning holes 404, fixing holes 406, etc. at positions corresponding to each other, and the positioning pins 902 and the positioning pins 813 of the clamp are inserted (see Fig.14 ), fastening member 91 (refer to Figure 2 ) and combined into one.

[0070] <First Core 42>

[0071] The first core 42 constitutes the overall rectangular shape of the core body K, and is formed in a horizontally long rectangular frame plate having a rectangular opening 422 in the center. The first core 42 is, for example, a rectangular frame body composed of a pair of short sides corresponding to the orthogonal portions 416 of the second core 43 and the third core 44 described later, and a pair of long sides corresponding to the mounting rod-shaped portions 417 and the connecting rod-shaped portions 418 of the second core 43 and the third core 44 described later.

[0072] In the first core 42, magnetic poles 412, 414, and magnet 36 are arranged in the rectangular opening 422 when viewed from the axial direction, and the second core 43 and the third core 44 are respectively in contact and joined with the first core 42 from one side of the axial direction. Thus, the first core 42, the second core 43, and the third core 44 are connected to the magnetic poles 412, 414, forming a magnetic circuit surrounding the magnetic poles 412, 414 and the magnet 36 from all sides.

[0073] <Second Core 43 and Third Core 44>

[0074] The second core 43 and the third core 44 are identical components formed in the same shape and manufactured in the same manner.

[0075] The second core 43 and the third core 44 each include a rod-shaped rod portion 415 having magnetic poles 412 and 414 at the tip end thereof, an orthogonal portion 416 , a bridge rod portion 417 , and a connecting rod portion 418 .

[0076] Magnetic poles 412 and 414 have the same shape, are disposed opposite to each other on the outer periphery of magnet 36, and are formed in arc shapes corresponding to the outer periphery of magnet 36. Magnetic poles 412 and 414 are excited by energizing coils 461 and 462, and generate polarities corresponding to the energizing directions.

[0077] The magnetic poles 412 and 414 have an outer size such that the bobbin 47 wound with the coils 461 and 462 can be inserted from the front end side, and the bobbin 47 of the coil body 45 is inserted from the magnetic poles 412 and 414 side, and the coil body 45 is externally mounted on the core body K (specifically, the rod-shaped portion 415). In addition, the details of the positional relationship between the magnetic poles 412 and 414 and the magnet 36 will be described later.

[0078] The coil body 45 is mounted outside the rod-shaped portion 415 (see Figure 2 , Figure 5 to Figure 7 ), an orthogonal portion 416 is branched and extended at the base end of the rod-shaped portion 415 in a direction orthogonal to the rod-shaped portion 415.

[0079] A bridging rod portion 417 and a connecting rod portion 418 are connected to both ends of the orthogonal portion 416 , and the bridging rod portion 417 and the connecting rod portion 418 extend in parallel with the rod portion 415 .

[0080] In the core body K, the pair of orthogonal portions 416 together with a pair of side portions formed by the bridge rod-shaped portion 417 and the connecting rod-shaped portion 418 form a rectangular frame-shaped magnetic path surrounding the rectangular opening 422 .

[0081] The mounting rod-shaped portion 417 of the second core 43 and the connecting rod-shaped portion 418 of the third core 44 are arranged adjacent to each other on a straight line, and the mounting rod-shaped portion 417 of the third core 44 and the connecting rod-shaped portion 418 of the second core 43 are arranged adjacent to each other on a straight line. The mounting rod-shaped portion 417 and the connecting rod-shaped portion 418 may also be configured to abut against the connecting rod-shaped portion 418 and the mounting rod-shaped portion 417 of other adjacent cores.

[0082] At least one of the bridge rod portion 417 and the connection rod portion 418 is provided with a recessed portion 480 in which the convex magnetic pole, ie, the angular position holding portion 48 is arranged.

[0083] That is, recess 480 is not formed by both bridge rod 417 and connecting rod 418 at a pair of opposing sides of the magnetic path where rod 415 is thickened. That is, first core 42, second core 43 and third core 44 are divided to avoid recess 480.

[0084] The recess 480 is formed at a substantially central portion of one side of a rectangular frame-shaped magnetic circuit formed by the bridge rod portion 417 and the connecting rod portion 418 , that is, at a portion facing the magnet 36 in a direction perpendicular to the axial direction.

[0085] In the present embodiment, the core body K surrounds the rod-shaped portions 415 having the magnetic poles 412 and 414 from all sides in a direction orthogonal to the axial direction together with the first core 42, the second core 43, and a portion of the third core 44 together with the magnet 36. Specifically, a portion of the second core 43 and the third core 44 is a rectangular surrounding portion consisting of a pair of orthogonal portions 416, a pair of mounting rod-shaped portions 417, and a pair of connecting rod-shaped portions 418.

[0086] This prevents foreign matter from coming into contact with coils 461 and 462 from the outside. In addition, the thickness of the core body K (axial length, thickness of the magnetic path) is the same at any position, and the length of the orthogonal portion 416 is shorter than a side portion formed by the mounting rod portion 417 and the connecting rod portion 418.

[0087] <Coil body 45>

[0088] The coil body 45 is formed by winding coils 461 and 462 around cylindrical bobbins 47 and 47. The bobbins 47 are attached to the rod-shaped portions 415 of the second core 43 and the third core 44, respectively.

[0089] The ends of the coils 461 and 462 are connected to metal terminals 472 embedded in the bobbin 47. The bobbin 47 is inserted outside the rod-shaped portion 415 of the second core 43 and the third core 44, so that the coils 461 and 462 are arranged around the rod-shaped portion 415.

[0090] By externally attaching the bobbins 47 to the rod-shaped portions 415, the coils 461 and 462 are respectively arranged adjacent to the magnetic poles 412 and 414. The winding directions of the coils 461 and 462 are set so that magnetic flux is appropriately generated from one side of the magnetic poles 412 and 414 toward the other side when power is supplied. In addition, the metal terminal 472 is arranged in a state of protruding toward one side (top cover 60 side) in the axial direction.

[0091] <Angle position holding section (also referred to as rotation angle position holding section, force applying section) 48>

[0092] Fig. 9 yes Figure 7 An enlarged view of the angular position maintaining portion is shown.

[0093] like Figure 7 to Figure 9 As shown, the angular position holding portion 48 faces the magnet 36 in the radial direction of the rotating shaft 24 and is disposed between the plurality of magnetic poles 412 and 414 in the circumferential direction of the rotating shaft 24 (or the magnet 36). The angular position holding portion 48 attracts the magnet 36 to bias the unit movable body 20 toward the initial position of the reciprocating rotation.

[0094] That is, the angle position holding portion 48 forms a magnetic spring with the rod-shaped portion 415 and the magnet 36. In particular, in a normal state (non-energized state) when the coils 461 and 462 are not energized, the angle position holding portion 48 maintains the rotation angle position of the magnet 36, that is, the rotation angle position of the rotating shaft 24, at the initial position by means of the magnetic spring formed between the angle position holding portion 48 and the magnet 36.

[0095] The initial position is the initial position of the magnet 36 when it performs a reciprocating rotation action, and is the reference position of the swing of the magnet 36. It is a neutral position where the magnet 36 is moved by the same length from the position where the magnet 36 is attracted by both the magnetic poles 412 and 414. When the magnet 36 is in the initial position, Fig. 9 As shown, magnetic pole switching portion (boundary portion) 363 of magnetic poles 361, 362 of magnet 36 is located opposite magnetic poles 412, 414. The mounting position of mirror unit 3 is adjusted based on the state where magnet 36 is located at the neutral position.

[0096] The angle position holding part 48 is a magnetic body, and uses a permanent magnet, and functions as a force applying part. The angle position holding part 48 is respectively composed of a pair of permanent magnets sandwiching the magnet 36. Thus, the pair of angle position holding parts 48 respectively generate magnetic attraction between different magnetic poles of the magnet 36, and a magnetic spring is formed by the magnetic attraction, and the magnet 36 is attracted by both sides of the angle position holding part 48, so that the magnet 36 is located at the initial position.

[0097] Thus, the magnet (permanent magnet) of the angular position holding portion 48 attracts the magnet (permanent magnet) 36 to determine the initial position during reciprocating rotation. Thus, the movable body 20 including the magnet 36 can stably generate torque and generate the maximum torque at the initial position.

[0098] Fig. 10A 2 is a diagram showing a state where the angle retaining portion is installed in the recessed portion. Fig. 10B It is a figure which shows the state which removed the angle holding part from the recessed part.

[0099] The angular position holding portion 48 is provided on each of the second core 43 and the third core 44, and is installed in a manner of being embedded in the recessed portions 480 disposed opposite to each other. Fig. 10A In FIG. 4 , the angle position holding portion 48 is shown to be installed in the recess 480 of the second core 43. Fig. 10B , a state in which the angular position holding portion 48 is removed from the recessed portion 480 is shown.

[0100] The angle position holding portion 48 embedded in the recess 480 is installed in a manner that a portion thereof protrudes inward from the inner side surface (the surface opposite to the rod-shaped portion 415) of the mounting rod-shaped portion 417 (a side portion serving as a magnetic circuit) of the second core 43. In addition, a circular cutout portion is formed at a corner portion 482 of the recess 480, and the cutout portion serves as an escape portion for the corner portion of the angle position holding portion 48 installed in the recess 480, and absorbs tolerance to appropriately position the angle position holding portion 48. In addition, the cutout portion functions as a bonding accumulation portion when bonding the angle position holding portion 48.

[0101] Angular position holding parts 48 are arranged to sandwich magnet 36 disposed at the center of the opposing direction of magnetic poles 412, 414 between magnetic poles 412, 414, and to face each other in directions perpendicular to both the opposing direction and the axis. A pair of angular position holding parts 48 are arranged so that different poles face each other and have the same function.

[0102] The structure using a permanent magnet as the angle position holding portion 48 is not limited thereto, and any magnetic body (particularly a ferromagnetic body) that forms a magnetic spring with the magnet 36 may be used. Fig.11 As shown, it is also possible to configure such that one of the pair of angular position holding portions 48, which are convex magnetic poles, 48A is integrally provided with the core (for example, the mounting rod-shaped portion 417 of the third core 44) that forms the magnetic body (ferromagnetic body), i.e., the magnetic circuit. In this case, the angular position holding portion 48A is preferably configured with the same outer shape as the angular position holding portion 48 to be configured.

[0103] <Bottom Cover 50 and Top Cover 60>

[0104] Figure 2 to Figure 6 The bottom cover 50 and the top cover 60 shown are made of conductive materials, for example, and function as electromagnetic shielding members of the electromagnetic drive unit. In addition, the bottom cover 50 and the top cover 60 rotatably support the rotating shaft 24 and function as shaft support bodies of the unit body 4.

[0105] The bottom cover 50 and the top cover 60 are plate-like bodies formed of, for example, aluminum or an aluminum alloy, and have shaft openings 53 and 63 through which the rotating shaft 24 is inserted. The bottom cover 50 and the top cover 60 allow the rotating shaft 24 to be inserted through the shaft openings 53 and 63, and clamp the core assembly 40 and are fixed to the core assembly 40. By using aluminum or an aluminum alloy as an electromagnetic noise shielding material in the bottom cover 50 and the top cover 60, a structure with high design freedom and sufficient rigidity can be achieved.

[0106] The bottom cover 50 and the top cover 60 are arranged on both sides of the core assembly 40 in the axial direction, respectively, to prevent foreign matter and other impurities from entering the core assembly 40 from the axial direction and to suppress the incidence of noise and the emission of noise (magnetic flux) from the core body K to the outside.

[0107] The bottom cover 50 and the top cover 60 have plate-shaped main bodies having shaft openings 53 and 63 at the center. Bearings 54 and 64 are fitted into the shaft openings 53 and 63 , respectively, and are located on the same axis.

[0108] In the bottom cover 50, the joint surface with the core assembly 40 is provided along the outer periphery of the main body, and is formed into a frame shape corresponding to the outer shape of the first core 42. Figure 2 as well as Figure 5 As shown, a retaining ring 56 fitted on the rotating shaft 24 is arranged adjacent to the back side of the bearing 54 (the side opposite to the core assembly 40), and the bearing 54 is arranged so as not to fall off from the bottom cover 50. The bearing 54 is composed of, for example, a rolling bearing or a sliding bearing, and rotatably supports the rotating shaft 24 inserted therethrough.

[0109] The top cover 60 includes a top cover body 62 that has a shaft opening 63 at the center and covers the core assembly 40 in the axial direction, and a junction substrate 66 .

[0110] The bearing 64 is mounted in the shaft opening 63 of the top cover body 62 so as to be fitted toward the other end side of the rotating shaft 24 and not to fall off from the other end side.

[0111] The top cover body 62 is provided with a terminal opening 65 into which the metal terminal 472 of the coil body 45 is inserted, and the metal terminal 472 inserted through the terminal opening 65 is connected to the relay substrate 66. Figure 5 In the embodiment, the metal terminal 472 is electrically connected to the relay substrate 66 via the solder fillet (solder) 4722. According to this structure, only by mounting the top cover 60 on the core assembly 40, the coils 461 and 462 of the core assembly 40 can be configured to be connectably arranged on the relay substrate 66, and can be easily connected and supplied with power from an external device via the relay substrate 66.

[0112] The top cover body 62 is formed into a rectangular tube with a lid, that is, a box shape, and has a preload spring 37 inserted outside the rotating shaft 24 disposed therein. A relay substrate 66 is disposed on the outer surface of the cover of the top cover body 62, and constitutes the cover surface.

[0113] The preload spring 37 is externally inserted into the rotating shaft 24, compressed in the axial direction, and applies force to the abutting parts in the axial direction. The preload spring 37 is arranged between the bearing 64 and the magnet 36, and is connected to the magnet 36 via a receiving portion 67 for setting the spring. That is, the receiving portion 67, that is, the spring setting ring is inserted and fixed between the preload spring 37 and the magnet 36, and the receiving portion 67 is arranged, so that the force generated by the preload spring 37 is not directly applied to the magnet 36 fixed by bonding or the like, and unnecessary force can be suppressed, thereby improving the reliability as an actuator.

[0114] The preload spring 37 applies an axial load to the bearing 64. In addition, the preload spring 37 also has a function of applying force to one end side so that the magnet 36 and the rotating shaft 24 are located in a positioned position. The preload spring 37 in the unit body 4 applies preload to the bearings (for example, ball bearings) 54 and 64 on both sides of the rotating shaft 24. The preload spring 37 is arranged between the movable object, namely the reflector portion 3, and the inner side of the bearings 54 and 64, and applies preload to the bearings 54 and 64 on both sides of the axial direction from the inside of the unit body (also called a motor) 4. As a result, in the unit body 4, a stable preload design can be performed without being affected by the outside. In addition, if the preload spring 37 is conical in shape, miniaturization can be achieved.

[0115] Figures 12A to 12C It is a figure which shows an example of a preload spring.

[0116] like Fig. 12A As shown, the preload spring 37 is a coil spring formed by winding a circular steel wire into a spiral shape in a conical shape, and the diameters of one end and the other end are different. Fig. 12B As shown in FIG. 1 , the preload spring 37 may also be replaced by a cylindrical coil spring 37A formed by winding a round steel wire into a spiral shape. In addition, in place of the preload spring 37, a Fig. 12C As shown, the spring 37B is a wave spring having a shape in which a plate-like steel wire is wound in a spiral or annular shape and a wave is added, and the shape is a spring with a relatively low height in the expansion and contraction direction.

[0117] The magnet 36 is arranged to be aligned in the axial direction with the stopper 27 interposed therebetween with respect to the bearing 54 which is fitted to the bottom cover 50 and whose movement toward one end side is restricted.

[0118] That is, the movement of the magnet 36 toward one end in the axial direction is restricted, and the preload spring 37 applies force from the other end to one end, thereby restricting the movement of the magnet 36 in the axial direction (thrust direction, bearing 64 side) relative to the unit body 4. Thus, the magnet 36 is always located at a predetermined position in the core assembly 40 (a position opposite to the magnetic poles 412, 414 and the angular position holding portion 48).

[0119] In addition, since the rotation shaft 24 is positioned in the axial direction, Figure 2 The parts (encoder disc 74, etc.) of the angle detection unit 70 provided on the other end side of the rotating shaft 24 are positioned in the axial direction. As a result, the parts of the angle detection unit 70, such as the encoder disc 74, do not move in the axial direction with the rotating shaft 24 and do not collide with other parts.

[0120] The rotating shaft 24 is inserted through the shaft opening 63 of the top cover 60 via the bearing 64, and the end of the rotating shaft 24 protrudes from the relay substrate 66. The encoder disk 74 of the angle detection unit 70 is fixed to the protruding end. In addition, the bearing 64 is installed in a state where the movement in the penetration direction is restricted by the flange portion of the bearing 64 abutting against the opening edge portion on the side of the core assembly 40 by passing through the shaft opening 63 from the core assembly 40 side. In addition, the bearing 64 is composed of, for example, a rolling bearing, but may also be composed of a bearing such as a sliding bearing.

[0121] <Unit Movable Body 20>

[0122] The magnet 36 and the core assembly 40 together constitute an electromagnetic drive unit, and cause the rotating shaft 24 to reciprocate.

[0123] like Fig. 9 As shown, the magnet 36 is a ring-shaped magnet in which the N pole 361 and the S pole 362 are alternately arranged in the circumferential direction. The magnet 36 is arranged in a space surrounded by the magnetic poles 412, 414 and the angular position holding portion 48 of the core body K, and is completely opposite to the magnetic poles 412, 414 and the angular position holding portion 48 in a direction orthogonal to the axial direction. In addition, the polarity of the magnet 36 may also be that the magnetic pole 361 is the S pole and the magnetic pole 362 is the N pole.

[0124] In addition, the magnet 36 is preferably arranged with a constant gap G between the magnetic poles 412 and 414 and the angular position holding portion 48 .

[0125] The magnet 36 generates magnetic force (attractive force and repulsive force) between the magnetic poles 412 and 414 having polarities corresponding to the energizing direction by the first to third cores 42 to 44 (particularly the rod-shaped portion 415 ) that are excited when the coils 461 and 462 are energized.

[0126] In this embodiment, if Fig. 9 As shown, the magnet 36 has a magnetic pole switching portion 363 which is arranged axially along the rotating shaft 24 and serves as a boundary of different polarities and switches the polarity. The magnet 36 is, for example, a two-pole magnet magnetized in a manner of being equally divided into an N pole 361 and an S pole 362. The number of magnetic poles of the magnet 36 (two in this embodiment) is equal to the number of magnetic poles 412 and 414 of the core body K. In addition, the magnet 36 can also be magnetized to more than two poles depending on the amplitude when it is movable. In this case, the magnetic pole portion of the core body K is set corresponding to the magnetic pole of the magnet 36.

[0127] In the magnet 36, when the coils 461 and 462 are not energized, the N pole 361 and the S pole 362 are attracted to the angle position holding portion 48 and adsorbed to each other, and are respectively held in the facing position. At this time, the magnet 36 is kept in the neutral position, that is, the initial position when performing the forward movement and the return movement. In the neutral position, the magnetic pole switching portion 363 of the magnet 36 faces the magnetic poles 412 and 414, so that the drive unit 2 can generate the maximum torque and stably drive the movable body.

[0128] In addition, the magnet 36 is composed of, for example, a two-pole magnet. Thus, the magnet 36 can easily drive the movable object with a high amplitude by cooperating with the iron core body K, and can achieve improved driving performance. In addition, in the embodiment, the case where the magnet 36 has a pair of magnetic pole switching parts 363 is described, but it can also have more than two pairs of magnetic pole switching parts 363.

[0129] <Angle Detection Unit 70>

[0130] The angle detection unit 70 can detect the rotation angle of the movable body including the magnet 36 and the rotating shaft 24, and control the rotation angle position and the rotation speed of the movable body, specifically, the movable object, ie, the mirror portion 3 during driving.

[0131] like Figure 1 , Figure 2 as well as Figure 5 As shown, the angle detection unit 70 is mounted in layers in the axial direction on the top cover 60 of the unit body 4. The angle detection unit 70 includes a sensor cover 72, an encoder disk 74, an encoder wheel 76, and a sensor substrate 78 on which a photosensor (not shown) is mounted.

[0132] The sensor cover 72 is attached to the top cover 60 via a fastening member 93 so as to cover the top cover 60 .

[0133] The sensor cover 72 has a through hole 73, and the other end of the rotating shaft 24 is arranged in the through hole 73. The other end is mounted with an encoding disk 74 and an encoding wheel 76. A sensor substrate 78 is arranged to cover the sensor cover 72, and a light sensor mounted on the sensor substrate 78 is arranged opposite to the encoding disk 74 in the axial direction, and irradiates light orthogonally to the encoding disk 74.

[0134] The code disk 74 is annular, fixedly mounted on the rotating shaft 24 via the cylindrical portion of the inner circumference, and rotates integrally with the magnet 36 and the reflector portion 3. The rotational position of the code disk 74 is set to be the same as the rotational position of the rotating shaft 24, and the optical sensor emits light to the code disk 74, and detects the rotational position (angle) of the code disk 74 based on the reflected light. Thus, the rotational position of the magnet 36 and the reflector portion 3 can be detected by the optical sensor.

[0135] In this way, the sensor substrate 78 is mounted on the sensor cover 72, covers the rotation angle sensor parts such as the optical sensor, the code disk 74 and the code wheel 76, and stores them in the sensor cover 72. As a result, foreign matter and other impurities can be prevented from entering the sensor cover 72 of the angle detection unit 70, and light interference can be prevented, so that stable detection can be performed.

[0136] In the unit body 4, the mirror portion 3 is supported by the rotating shaft 24 protruding from the bottom cover 50 side, and an angle detection unit 70 is provided on the top cover 60 side opposite thereto to detect the rotation angle of the rotating shaft 24 protruding from the top cover 60 side. The angle detection unit 70 is attached to the outer surface side of the top cover 60.

[0137] In the angle detection unit 70, it is mounted on a sensor substrate 78 mounted on the top cover 60. The optical sensor can be easily removed by simply removing the sensor substrate 78 from the top cover 60. In addition, wiring for a driving power supply of the vibration actuator 1 connected to the relay substrate 66 may also be installed on the sensor substrate 78.

[0138] Therefore, when a malfunction occurs in the angle detection unit 70, each sensor component can be easily replaced regardless of the structure. In addition, the angle detection unit 70 can be assembled at the final stage of assembly.

[0139] As a result, the angle detection unit 70 having the expensive optical sensor (not shown) can be assembled after confirming that the other parts are assembled normally. Thus, the risk of wasting the expensive angle detection unit 70, especially the optical sensor (not shown) due to poor assembly of other parts can be suppressed. In addition, after installation, even if there is a malfunction in the actuator, by removing the sensor substrate 78, the optical sensor mounted on the sensor substrate can be immediately removed.

[0140] Fig.13 It is a diagram showing a magnetic circuit structure of an electromagnetic drive unit based on a rotary reciprocating drive actuator.

[0141] The two magnetic poles 412 and 414 of the core body K of the core assembly 40 are arranged so as to sandwich the magnet 36 with an air gap G therebetween. Fig. 9 As shown, the magnet 36 is held in the neutral position by the magnetic attraction between the magnet 36 and the angular position holding portion 48 .

[0142] In this neutral position, one of the S pole 362 and the N pole 361 of the magnet 36 (at Fig.13 The S pole 362 in the middle) is attracted by the angle position holding portion 48 (refer to Fig.13At this time, the magnetic pole switching portion 363 is opposite to the center position of the magnetic poles 412 and 414 of the core body K.

[0143] When the coils 461 and 462 are energized, the core K is excited, and the polarity corresponding to the energization direction is generated at the magnetic poles 412 and 414. Fig.13 As shown, when the coils 461 and 462 are energized, a magnetic flux is generated inside the core body K, and the magnetic pole 412 becomes an S pole, and the magnetic pole 414 becomes an N pole. As a result, the magnetic pole 412 magnetized to the S pole and the N pole 361 of the magnet 36 attract each other, and the magnetic pole 414 magnetized to the N pole and the S pole 362 of the magnet 36 attract each other. In addition, a torque in the F direction is generated around the rotating shaft 24 in the magnet 36, and the magnet 36 rotates in the F direction. In conjunction with this, the rotating shaft 24 also rotates in the F direction, and the reflector unit 3 fixed to the rotating shaft 24 also rotates in the F direction.

[0144] Next, if the coils 461 and 462 are energized in the opposite direction, the flow of the magnetic flux generated inside the core body K becomes the opposite direction, the magnetic pole 412 becomes the N pole, and the magnetic pole 414 becomes the S pole. The magnetic pole 412 magnetized to the N pole and the S pole 362 of the magnet 36 attract each other, and the magnetic pole 414 magnetized to the S pole and the N pole 361 of the magnet 36 attract each other. Moreover, a torque in the opposite direction to the F direction is generated around the rotating shaft 24 by the magnet 36, and the magnet 36 rotates in the opposite direction to the F direction. Along with this, the rotating shaft 24 also rotates, and the reflector unit 3 fixed to the rotating shaft 24 also rotates.

[0145] The rotary reciprocating drive actuator 1 rotary reciprocatingly drives the mirror portion 3 by repeating the above-mentioned operation.

[0146] In practice, the rotary reciprocating drive actuator 1 is powered by a power supply unit (e.g., a power source equivalent to a power source) via a relay substrate 66. Fig.21 The driving signal supply unit 103) inputs the AC wave drive to the coils 461 and 462.

[0147] That is, the energizing directions of the coils 461 and 462 are switched periodically. When the energizing directions are switched, the angular position holding portion 48 and the magnet 36 are magnetically attracted to each other, that is, the restoring force of the magnetic spring ( Fig.13 The magnet 36 is urged to return to the neutral position by the magnetic spring torque FM shown in the figure and the magnetic spring torque in the opposite direction thereof. As a result, the torque in the F direction around the axis and the torque in the direction opposite to the F direction act alternately on the movable body. As a result, the movable body is driven to reciprocate.

[0148] The driving principle of the rotary reciprocating drive actuator 1 will be briefly described below. In the rotary reciprocating drive actuator 1 of the present embodiment, the inertia moment of the movable body is J [kg·m 2], the spring constant of the magnetic spring (magnetic poles 412, 414, angle position holding portion 48 and magnet 36) in the torsion direction is set to K sp In this case, the movable body 20 is in resonance with respect to the fixed body (unit body 4) at a resonance frequency F calculated by equation (1). r [Hz] Vibration (reciprocating rotation).

[0149] [Formula 1]

[0150]

[0151] F r : Resonance frequency [Hz]

[0152] J: Inertia moment [kg·m 2 ]

[0153] K sp : Spring constant [N·m / rad]

[0154] The movable body constitutes the mass part in the vibration model of the spring mass system. Therefore, when the resonance frequency F of the movable body is input to the coils 461 and 462, r When an AC wave with the same frequency as the movable body is supplied, the movable body enters a resonant state. That is, the resonant frequency F of the movable body can be input to the coils 461 and 462 from the power supply unit. r The AC waves of substantially equal frequency cause the movable body to vibrate efficiently.

[0155] The following are motion equations and circuit equations that represent the driving principle of the rotary reciprocating drive actuator 1. The rotary reciprocating drive actuator 1 is driven based on the motion equation shown in equation (2) and the circuit equation shown in equation (3).

[0156] [Formula 2]

[0157]

[0158] J: Inertia moment [kg·m 2 ]

[0159] θ(t): angle [rad]

[0160] K t : Torque constant [N·m / A]

[0161] i(t): current [A]

[0162] K sp : Spring constant [N·m / rad]

[0163] D: Attenuation coefficient [N·m / (rad / s)]

[0164] TLoss : Load torque [N·m]

[0165] [Formula 3]

[0166]

[0167] e(t): voltage [V]

[0168] R: resistance [Ω]

[0169] L: Inductance [H]

[0170] K e : Back electromotive force constant [V / (rad / s)]

[0171] That is, the inertia moment J [kg·m 2 ], rotation angle θ(t)[rad], torque constant K t [N·m / A], current i(t)[A], spring constant K sp [N·m / rad], attenuation coefficient D [N·m / (rad / s)], load torque T Loss [N·m] etc. can be changed appropriately within the range satisfying equation (2). In addition, voltage e(t) [V], resistance R [Ω], inductance L [H], back electromotive force constant K e [V / (rad / s)] can be changed appropriately within the range satisfying the formula (3).

[0172] In this way, the rotary reciprocating drive actuator 1 is driven by the inertia moment J of the movable body and the spring constant K of the magnetic spring. sp Determine the resonant frequency F r When the coil is energized by a corresponding AC wave, a high-efficiency vibration output can be obtained.

[0173] Fig.14 It is a figure for demonstrating the assembly method of the iron core body.

[0174] When assembling the rotary reciprocating drive actuator 1, for example, a positioning jig 810 having a recessed portion in the center into which the unit body 4 can be inserted is used. The bottom cover 50 and the first iron core 42 are arranged in the recessed portion of the positioning jig 810 to restrict horizontal movement during assembly. Then, the positioning pin 902 and the positioning pin 813 of the jig are inserted into the positioning hole 404 of the first iron core 42, so that the positioning pin 902 and the positioning pin 813 of the jig are arranged in a state of protruding from the upper surface of the first iron core 42. In addition, the positioning pin 813 of the jig is fixed to the positioning jig 810 by being pressed in.

[0175] On the other hand, the coil body 45 is inserted into the rod-shaped portion 415 of the second core 43 and the third core 44, and the coil body 45 is assembled with the magnetic poles 412 and 414 arranged adjacent to each other. In addition, the permanent magnet, i.e., the angular position holding portion 48, is installed in the recessed portion 480 of each of the second core 43 and the third core 44. Then, the positioning pin 902 protruding from the positioning hole 404 of the first core 42 corresponding to them and the positioning pin 813 of the fixture provided in the positioning fixture 810 are inserted into the positioning holes 404 of each of the second core 43 and the third core 44. Thus, the second core 43 and the third core 44 are combined and appropriately joined to the first core 42.

[0176] At this time, the fixing pin is first inserted into the clearance hole (long hole) 404-1 in the positioning hole 404, and the positioning pin 813 of the positioning fixture 810 can be inserted and installed in the other positioning hole 404 at the correct position, thereby accurately combining with each other. In addition, since the second core 43 is installed on the first core 42 by means of the positioning pin 902 inserted into the positioning hole 404-2, the positioning pin 902 also acts as a horizontal stopper for the second core 43 or the third core 44.

[0177] The unit body 4 can be easily assembled even under the influence of the magnetic attraction force of the permanent magnet, i.e., the angle position holding portion 48, and the magnet 36. For example, when the magnet 36 is arranged at a predetermined position and then assembled, the second core 43 and the third core 44 are attracted by the magnet 36, making it difficult to assemble. However, in the present embodiment, a positioning hole 404 is provided in the first to third cores 42 to 44, which serves as a rotation stop during assembly. Thus, when assembling the first core 42, the second core 43, and the third core 44, the first core 42, the second core 43, and the third core 44 can be easily and accurately assembled while preventing rotation, thereby improving the workability during assembly.

[0178] Fig.15 This is a diagram for explaining a method of installing a rotary reciprocating drive actuator.

[0179] In the rotary reciprocating drive actuator 1 , the bracket 80 is provided with a fixing hole 806 , and the device frame 500 is provided with a pair of mounted wall portions 502 , 503 to which the rotary reciprocating drive actuator 1 is mounted.

[0180] Mounting holes 506 and positioning protrusions 508 are provided at predetermined positions on the upper surfaces of the mounted wall portions 502 and 503 .

[0181] When the rotary reciprocating drive actuator 1 is mounted on the device frame 500, the fixing hole 806 of the bracket 80 is made to correspond to the mounting hole 506 of the mounted wall portion 502, 503, and the bracket 80 is arranged on the mounted wall portion 502, 503. At this time, the positioning protrusion 508 is inserted into the positioning hole 807 of the bracket 80. The positioning hole 807 of the bracket 80 is a shape with a clearance relative to the shape of the positioning protrusion 508. Therefore, after the bracket 80 is placed on the mounted wall portion 502, 503, the mounting holes 506 and the fixing holes 806 are aligned with each other so as to have the same opening, and the fastening member 99 is inserted, thereby fixing the two appropriately and simply.

[0182] The rotary reciprocating drive actuator 1 can be positioned / fixed in a direction parallel to the rotating shaft 24. Thus, it can be fixed at a position where the size can be specified based on the driving shaft. In addition, the rotating shaft 24 can be vertically erected and fixed in a direction parallel to the rotating shaft 24, so the assembly is high.

[0183] In this way, by performing positioning and fixing in a direction parallel to the rotation axis 24 , it is possible to perform positioning and fixing with high accuracy while adding less dimensions than other parts.

[0184] (Implementation Method 2)

[0185] Fig.16 is a perspective view of the appearance of a scanning device having a rotary reciprocating drive actuator according to Embodiment 2, Fig.17 This is an exploded perspective view of a scanning device having a rotary reciprocating drive actuator according to a second embodiment.

[0186] The rotary reciprocating drive actuator 1A has the same function as the rotary reciprocating drive actuator 1 , and includes a drive unit 2A, a mirror portion 3A, a base portion 80A, and an angle detection unit 70 .

[0187] Fig.16 as well as Fig.17 The illustrated reciprocating drive actuator 1A is not a cantilever type as compared to the reciprocating drive actuator 1 , but has a structure in which the mirror portion 3 to be reciprocated and rotationally driven by the reciprocating drive actuator is held by a base portion 80A in a manner sandwiching the mirror portion 3 .

[0188] That is, it is a rotary reciprocating drive actuator that can efficiently support the mirror portion in a reciprocating and rotatable manner when the mirror portion is enlarged.

[0189] Specifically, the drive unit 2A has a different length of the rotating shaft 24A from the drive unit 2, and the other structures are the same. Therefore, hereinafter, regarding the rotary reciprocating drive actuator 1A, only the different structures compared with the rotary reciprocating drive actuator 1 will be described, and the description of other identical structures will be omitted.

[0190] The drive unit 2A includes a rotating shaft 24A having a length that allows the rotating shaft 24A to pass through the wall portion 87 , compared to the drive unit 2 .

[0191] The drive unit 2A has the unit body 4 mounted and fixed to a base 80A having a pair of opposing walls 85 and 87. The drive unit 2A has the rotating shaft 24A protruding from the unit body 4 spanned between the pair of walls 85 and 87, and the mirror unit 3A disposed between the pair of walls 85 and 87.

[0192] The unit body 4A is fixed to the outer surface of the wall 85 of the pair of wall portions 85 and 87 of the base portion 80A, and the rotation shaft 24A protruding from the unit body 4A is inserted through the insertion hole 852 of the wall portion 85. The reflector portion 3A fixed to the rotation shaft 24A is arranged between the pair of wall portions 85 and 87 together with the spacer 36, and the front end of the rotation shaft 24A is reciprocatingly rotatably supported on the wall portion 87 via the bearing 84 filled in the opening portion 872. In addition, it can be said that the bearing 84 and the wall portion 87 constitute a rotation support portion.

[0193] The opening 872 of the wall 87 is provided with a preload spring 370 for applying preload to the bearing 84 together with the bearing 84 embedded therein. The preload spring 370 is the same as the preload spring 37, and therefore the description thereof is omitted. A cover plate 88 is mounted on the outer surface of the wall 87 via a fastening member 89 to abut against the preload spring 370, so that the preload spring 370 is arranged in a state of applying preload to the bearing 84. In addition, a fixing hole, a notch, etc. are provided as a fixing unit for fixing the base 80A and, in turn, the rotary reciprocating drive actuator 1A.

[0194] Thus, even when the movable object such as the reflector portion 3A is enlarged, unlike the case of the cantilever structure, the front end of the rotating shaft 24A can be rotatably supported, so the behavior of the movable object can be stabilized, and the impact resistance and vibration characteristics can be ensured. In addition, the bearing 84 uses the same ball bearing as the bearings 54, 64, etc., but is not limited to this.

[0195] For example, the bearing 84 may also be Fig.18 A bushing made of resin is used as in the modified example 1 shown in the figure. This has substantially the same effect as that of a ball bearing and can achieve weight reduction.

[0196] (Implementation 3)

[0197] Fig.19 is a perspective view of the appearance of a scanning device having a rotary reciprocating drive actuator according to Embodiment 3, Fig. 20 This is an exploded perspective view of a scanning device having a rotary reciprocating drive actuator according to a third embodiment.

[0198] The rotary reciprocating drive actuator 1B has the same function as the rotary reciprocating drive actuator 1 , and includes a drive unit 2B, a mirror portion 3B, a base portion 80B, and an angle detection unit 70 .

[0199] Fig.19 as well as Fig. 20 The illustrated reciprocating drive actuator 1B is not a cantilever type as compared to the reciprocating drive actuator 1 , but has a structure in which the mirror portion 3 to be reciprocated and rotationally driven by the reciprocating drive actuator is held by a base portion 80B in a manner sandwiching the mirror portion 3 .

[0200] The reciprocating drive actuator 1B can be effectively supported in a reciprocating and rotatable manner when the mirror portion is enlarged.

[0201] Specifically, the drive unit 2B has a different length of the rotating shaft 24B from the drive unit 2, and the drive unit 2B has the same other structures as the drive unit 2. Hereinafter, only the different structures of the rotary reciprocating drive actuator 1B compared with the rotary reciprocating drive actuator 1 will be described, and the description of the other identical structures will be omitted.

[0202] Compared with the drive unit 2 , the drive unit 2B includes a rotation shaft 24B having a length that is inserted through a pair of wall portions 85B and 87B of the base portion 80B, and a reflector portion 3B that is larger than the reflector portion 3 is mounted on the rotation shaft 24B.

[0203] The drive unit 2B has a unit body 4B mounted and fixed to a base 80B having a pair of opposing walls 85B and 87B. The drive unit 2B has a rotating shaft 24B protruding from the unit body 4B mounted between the pair of walls 85B and 87B, and has a reflector 3B disposed between the pair of walls 85B and 87B.

[0204] The unit body 4B is fixed to the outer surface of the wall portion 85B of the base portion 80B, and the rotation shaft 24B protruding from the unit body 4B is inserted through the insertion hole 852B of the wall portion 85B. The reflector portion 3B fixed to the rotation shaft 24B is arranged between a pair of wall portions 85B and 87B together with the spacer 36, and the front end of the rotation shaft 24B is supported by the wall portion 87B via the bearing 84 embedded in the opening portion 872B so as to be reciprocatingly rotatable.

[0205] The opening 872B of the wall 87B is provided with a preload spring 370 for applying preload to the bearing 84 together with the bearing 84 inserted therein. The preload spring 370 is the same as the preload spring 370, and thus the description thereof is omitted. A cover plate 88B abutting against the preload spring 370 is attached to the outer surface of the wall 87B via a fastening member 89B, so that the preload spring 370 is arranged in a state of applying preload to the bearing 84.

[0206] The bottom plate portion 86B of the base portion 80B is provided with fixing holes, cutouts, and the like as fixing means for fixing the base portion 80B and, in turn, the rotary reciprocating drive actuator 1B.

[0207] Thus, even when the movable object such as the mirror unit 3B is enlarged, unlike the case of a cantilever structure, the tip of the rotation shaft 24B can be rotatably supported, so that the behavior of the movable object can be stabilized and shock resistance and vibration characteristics can be ensured.

[0208] In addition, in each embodiment, the bearings 54 and 64 use ball bearings, but are not limited to this. For example, the bearing 84 may also be Fig.18 A bushing made of resin is used as in the modified example 1 shown in the figure. This has substantially the same effect as that of a ball bearing and can achieve weight reduction.

[0209] In addition, the bearing 84 of the third embodiment may be a bushing made of resin instead of a ball bearing.

[0210] Fig.21 1 is a block diagram showing a main part configuration of a scanner system 100 using the rotary reciprocating drive actuator 1 .

[0211] The scanner system 100 includes a laser light emitting unit (light irradiating unit) 101 , a laser control unit 102 , a drive signal supply unit 103 , and a position control signal calculation unit 104 in addition to the rotary reciprocating drive actuator 1 .

[0212] The laser light emitting unit 101 includes, for example, an LD (laser diode) as a light source and a lens system for converging laser light output from the light source, etc. The laser control unit 102 controls the laser light emitting unit 101. The laser light irradiated from the laser light emitting unit 101 enters the reflection mirror 34 of the rotary reciprocating drive actuator 1.

[0213] The position control signal calculation unit 104 generates and outputs a drive signal to control the rotation shaft 24 (reflector 34) to the target angular position with reference to the angular position of the rotation shaft 24 (reflector 34) obtained by the angle detection unit 70. For example, the position control signal calculation unit 104 generates a position control signal based on the obtained angular position of the rotation shaft 24 (reflector 34) and a signal indicating the target angular position after transformation using sawtooth waveform data stored in a waveform memory (not shown). The position control signal calculation unit 104 outputs the position control signal to the drive signal supply unit 103.

[0214] The drive signal supply unit 103 supplies a drive signal to the coils 461 and 462 of the reciprocating actuator 1 to adjust the angular position of the rotating shaft 24 (mirror 34) to a desired angular position based on the position control signal. Thus, the scanner system 100 can emit scanning light from the reciprocating actuator 1 to a predetermined scanning area.

[0215] <Conclusion>

[0216] As described above, the rotary reciprocating drive actuator 1 of the present embodiment includes the movable body 20, which includes: the rotating shaft (shaft portion) 24 to which the reflector portion (movable object) is connected; and the magnet 36 fixed to the outer periphery of the rotating shaft 24. The movable body 20 can reciprocate around the rotating shaft 24. In addition, the magnet 36 is a ring-shaped magnet with S poles 362 and N poles 361 alternately arranged on the outer peripheral surface in the circumferential direction.

[0217] In addition, the rotary reciprocating drive actuator 1 has a unit body 4 that reciprocates the movable body 20 by interacting with the magnet 36. The unit body 4 has a core assembly 40, which includes: a core body K having a plurality of magnetic poles (a pair of magnetic poles) 412, 414; and a plurality of coils 461, 462 that generate magnetic flux in the core body K when power is supplied. The unit body 4 arranges the core assembly 40 so that the plurality of magnetic poles 412, 414 are opposite to the outer periphery of the magnet 36 and the plurality of coils 461, 462 are parallel to each other. The plurality of magnetic poles 412, 414 extend on the same straight line on both sides of the radial direction of the rotating shaft 24 relative to the magnet 36.

[0218] The coils 461 and 462 sandwiching the magnet 36 are arranged on one axis in the radial direction of the magnet 36, and the core body K is a part (surrounding portion) of the core body (second core 43 and third core 44) K surrounding the coils 461 and 462 and the magnet 36, and constitutes a magnetic circuit portion connecting the magnetic poles 412 and 414. In addition, the core body K is provided with a force-applying portion, i.e., an angular position holding portion (magnet) 48, in a portion (recess 480) where the surrounding portion is cut.

[0219] According to this structure, when obtaining the magnetic path length, it is possible to design the length in only one axial direction and suppress the length in the direction perpendicular to the one axial direction. That is, if the direction perpendicular to the one axial direction is set as the height direction, the product can be made thinner.

[0220] That is, in the rotary reciprocating drive actuator 1, when the product size is expected to be miniaturized and thinned according to the situation while driving at a high amplitude, for example, in the case of a structure in which the coils 461 and 462 are arranged on one side and thinned, it can also be appropriately dealt with. That is, unlike in the past, if one axial direction, i.e., the direction of insertion of the bobbin, is shortened, the number of windings will not be reduced, and in addition, if the direction orthogonal to the insertion direction is shortened, the magnetic path cross-section of the iron core body constituting the magnetic path will not be reduced or thinned.

[0221] As described above, according to the rotary reciprocating drive actuator 1, further miniaturization and installation space saving can be achieved, and the actuator has shock resistance and vibration resistance characteristics, and can drive a movable object with a high amplitude in a more stable state via the shaft portion.

[0222] In addition, the angle position holding part (rotation angle position holding part) 48 is a magnet (permanent magnet), and has a plurality (here, a pair) of magnets 36 on the movable body side. The plurality of angle position holding parts 48 can more accurately position the movable body at the reference position of the movable body during reciprocating rotational drive, and reciprocate from this position, and reciprocate with a large torque can be reliably driven.

[0223] In addition, the movable object is the mirror unit 3 (particularly the mirror 34) that reflects the scanning light. Thus, the rotary reciprocating drive actuator 1 can be used for a scanner that performs optical scanning.

[0224] In the core assembly 40 of the present embodiment, the second core 43 and the third core are cores of exactly the same shape, and a pair of these cores are used and symmetrically arranged to form the core assembly 40. Therefore, by reducing the number of parts, assembly becomes easy and manufacturing costs can be reduced.

[0225] In addition, the core assembly 40 is provided with a recess 480 having a width that matches the magnet for mounting the magnet that becomes the angular position holding portion 48. Thus, when the angular position holding portion 48 is mounted on the core body K or (the second core 43 and the third core 44), when a clamp is required for positioning, it is not necessary to use a clamp, and the mounting can be easily performed, which can simplify the assembly work.

[0226] As mentioned above, the invention completed by the present inventors has been specifically described based on the embodiments. However, the present invention is not limited to the above-mentioned embodiments, and can be modified within a scope not departing from the gist thereof.

[0227] For example, in the embodiment, the movable object is described as the mirror unit 3, but the movable object is not limited to this. The movable object may be, for example, an imaging device such as a camera.

[0228] Furthermore, for example, in the embodiment, the case where the rotary-reciprocating drive actuator 1 is resonantly driven is described, but the present invention can also be applied to the case of non-resonant driving.

[0229] Possibility of Industrial Application

[0230] The present invention is applicable to, for example, LiDAR devices, scanner systems, etc.

[0231] Explanation of symbols

[0232] 1, 1A, 1B—rotational reciprocating drive actuator; 2, 2A, 2B—drive unit; 3, 3A, 3B—reflector portion; 4, 4A, 4B—unit body; 9, 89, 89B, 91, 93, 99—fastening member; 20—movable body; 24, 24A, 24B—rotation axis (axis portion); 27—stopper; 32, 32A, 32B—reflector bracket; 34, 34A, 34B—reflector; 36—magnet; 36—spacer; 37, 370—preload spring; 37A—coil spring; 37B—wave spring; 40—core assembly; 42—first core ; 43—second core (core of the same shape); 44—third core (core of the same shape); 45—coil body; 47—bobbin; 48, 48A—angle position holding portion (force applying portion); 50—bottom cover (first shaft support); 53, 63—shaft opening; 54, 64, 84—bearing; 56—retaining ring; 60—top cover (second shaft support); 62—top cover body; 65—terminal opening; 66—relay substrate; 67—receiving portion; 70—angle detection unit; 72—sensor cover; 73—through hole; 74—encoder disk; 76—encoder wheel; 78—sensor substrate; 8 0—bracket; 80A, 80B—base; 85, 85B, 87, 87B—wall; 86, 86B—bottom plate; 88, 88B—cover; 100—scanner system; 101—laser light emitting unit; 102—laser control unit; 103—drive signal supply unit; 104—position control signal calculation unit; 361—N pole (magnetic pole); 362—S pole (magnetic pole); 363—magnetic pole switching unit; 404, 404-2, 440—positioning hole; 404-1—clearance hole (long hole); 406—fixing hole; 412, 414—magnetic pole; 415—rod-shaped unit; 416 —orthogonal portion; 416—orthogonal portion; 417—mounting rod-shaped portion; 418—connecting rod-shaped portion; 422—rectangular opening; 440—positioning hole; 461, 462—coil; 472—metal terminal; 480—recess; 482—corner; 500—device frame; 502, 503—mounted wall portion; 506—mounting hole; 806—fixing hole; 807—positioning hole; 508—positioning protrusion; 810—positioning fixture; 852, 852B—through hole; 872, 872B—opening; 902, 903—positioning pin; 4722—solder foot (solder); K—coil body.

Claims

1. A rotary reciprocating drive actuator, characterized in that: have: a movable body having a shaft portion having a magnet fixed to an outer periphery thereof and capable of reciprocating rotation about the shaft portion; and a unit body which causes the movable body to reciprocate by interacting with the magnet, The unit body has: An iron core body having a pair of magnetic poles and a magnetic path portion, the pair of magnetic poles extending on the same straight line on both sides of the radial direction of the shaft portion relative to the magnet, and the magnetic path portion surrounding the pair of magnetic poles and the magnet and connecting the pair of magnetic poles; a pair of coil bodies, which are wound around the pair of magnetic poles and generate the interaction by energizing; as well as The urging portion is disposed in a recessed portion formed in the magnetic circuit portion at a position between the pair of magnetic poles in a circumferential direction of the shaft portion and urges the movable body toward an initial position of reciprocating rotation.

2. The rotary reciprocating drive actuator according to claim 1, characterized in that: The iron core body is composed of a plurality of segmented bodies. The plurality of divided bodies include a plurality of same-shaped iron cores that are symmetrically arranged around the magnet and each of which has one magnetic pole of the pair of magnetic poles and a portion of the magnetic path portion.

3. The rotary reciprocating drive actuator according to claim 2, characterized in that: The divided body is divided so as to avoid the concave portion.

4. The rotary reciprocating drive actuator according to claim 1, characterized in that: The recessed portion has a shape corresponding to a width of the biasing portion.

5. The rotary reciprocating drive actuator according to claim 1, characterized in that: Another urging portion is provided, which is arranged to face the urging portion with the magnet interposed therebetween and has the same function as that of the urging portion.

6. The rotary reciprocating drive actuator according to claim 4, characterized in that: When the magnet is located at the initial position, the magnetic pole switching portions of the magnet are configured to be arranged at positions symmetrical with respect to the plurality of magnetic poles in the circumferential direction.

7. The rotary reciprocating drive actuator according to claim 1, characterized in that: The magnet is magnetized into two poles.

8. The rotary reciprocating drive actuator according to claim 1, characterized in that: The force applying part is a magnet.

9. The rotary reciprocating drive actuator according to claim 5, characterized in that: The biasing portion is a permanent magnet, and the other biasing portion is a permanent magnet or a convex magnetic pole formed integrally with the magnetic circuit portion.

10. The rotary reciprocating drive actuator according to claim 1, characterized in that: The unit body has a pair of shaft supports which are arranged to sandwich the core body in the axial direction, cover the core body, the coil body, the magnet and the biasing portion from both sides in the axial direction, and rotatably support the inserted shaft portion.

11. The rotary reciprocating drive actuator according to claim 1, characterized in that: The unit body and the movable object are fixed to the shaft portion, and an end portion on the movable object side is rotatably supported by a rotation support portion.

12. The rotary reciprocating drive actuator according to claim 10, characterized in that: The pair of shaft supports has conductivity.

Images