JP2005121801A - Driving device, light quantity adjusting device and lens-driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving device realizing stable driving such that a large rotational angle is secured, while attaining miniaturization, reduction in cost and yielding high output. <P>SOLUTION: The driving device is provided with a rotor shaft 6 fixed at the inside diameter part of a magnet 5, a 1st outer magnetic pole part 1a arranged on the outer circumferential surface of the magnet with a prescribed gap, a 1st coil 2 arranged adjacent to the magnet in the shaft direction of the rotor shaft, wound around the 1st outside magnetic pole part and exciting the 1st outside magnetic pole part, a 2nd outer magnetic pole part 1b shifted in terms of phase by 180° with reference to the center of the magnet from the 1st outer magnetic pole part and arranged on the outer circumferential surface of the magnet with a prescribed gap, a 2nd coil 3 arranged adjacent to the magnet in the shaft direction of the rotor shaft, to be nearly side by side with the 1st coil on a plane perpendicular to the shaft direction of the rotor shaft, wound around the 2nd outer magnetic pole part and exciting the 2nd outer magnetic pole part. The 1st outer magnetic pole part and the 2nd outer magnetic pole part are excited to opposite poles. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a driving device suitable for a compact configuration, and a light amount adjusting device and a lens driving device having the driving device.

  The present applicant has proposed a drive device in the following light amount adjusting device disclosed in Patent Document 1 as a drive device that has a reduced diameter around the rotation axis and increased output.

  FIG. 10 shows an exploded perspective view of the drive device described in Patent Document 1, and FIG. 11 shows a side sectional view of the drive device described in Patent Document 1. As shown in FIG.

  101 is a magnet having an outer peripheral surface divided into two in the circumferential direction and alternately magnetized to S and N poles and having a permanent magnet that can rotate around the center of rotation, and 102 is arranged in the axial direction of the magnet 101. It is a coil. Reference numeral 103 denotes a stator that is excited by the coil 102 and has a tooth-shaped outer magnetic pole portion 103 a facing the outer peripheral surface of the magnet 101 and a cylindrical inner cylinder 103 b facing the inner peripheral surface of the magnet 101. An auxiliary stator 104 is fixed to the inner cylinder 103 b of the stator 103 and forms an inner magnetic pole portion together with the inner cylinder 103 b of the stator 103. The drive device in the light amount adjusting device is configured as described above.

  The magnet 101 includes shaft portions 101e and 101f so as to be rotatably held, and these are integrally formed. The outer magnetic pole portion 103a of the stator 103 faces the outer peripheral surface of the magnet 101 with a gap, and the inner cylinder 103b and the auxiliary stator 104 of the stator 103 face the inner peripheral surface of the magnet 101 with a gap.

  The drive device configured as described above reciprocally rotates the magnet 101 by switching the energizing direction of the coil 102 and switching the polarities of the outer magnetic pole portion 103a, the inner cylinder 103b, and the auxiliary stator 104. Further, the rotation restriction of the magnet 101 that reciprocates is performed by the drive pin 101 d coming into contact with the guide groove 105 a provided in the base plate 105.

In this driving device, the magnetic flux generated by energizing the coil flows from the outer magnetic pole part to the opposing inner magnetic pole part, or from the inner magnetic pole part to the opposing outer magnetic pole part, and between the outer magnetic pole part and the inner magnetic pole part. Acts effectively on the magnet located. In addition, by setting the distance between the outer magnetic pole part and the inner magnetic pole part to a distance corresponding to the thickness of the cylindrical magnet, the gap between the magnet and the outer magnetic pole part, and the gap between the magnet and the inner magnetic pole part, The resistance of the magnetic circuit composed of the magnetic pole part is made as small as possible. The smaller the resistance of the magnetic circuit, the more magnetic flux can be generated with less current, and the output is improved.
JP 2002-049076 A

  However, since the one proposed in Patent Document 1 has only one tooth-shaped outer magnetic pole portion 103a, the magnet 101 is attracted only in the direction in which the outer magnetic pole portion 103a faces when rotating, and the rotation is performed. The balance is bad and the loss is large. Here, if the magnet is divided and magnetized into four poles, the outer magnetic pole part can be made into two teeth, and the rotation balance is improved, but the rotation angle is smaller than that of the magnet divided into two poles. It will be halved.

  The axial length of the driving device is determined by the length of the coil 102, the length of the magnet 101, and the thickness of the stator 103. The outer diameter of the driving device is determined by the outer diameter of the inner cylinder 103b and the thickness of the coil 102 in the radial direction. Since it is determined by the thickness of the outer magnetic pole portion 103a, in order to increase the number of turns of the coil 102, the length of the magnet 101 is decreased, the thickness of the outer magnetic pole portion 103a is decreased, the length of the driving device is increased, or the driving device is increased. There is no choice but to increase the outside diameter. Here, if the length of the magnet is lowered, there is a limit because the output is lowered, and if the thickness of the outer magnetic pole portion 103a is reduced, magnetic saturation occurs and the output is lowered. Therefore, the outer diameter has to be increased in order to obtain a drive device having a high output and a shorter axial length.

  In addition, a predetermined interval is required between the inner diameter of the magnet 101 and the auxiliary stator 104 facing the magnet 101, and managing it at the time of manufacturing increases the cost.

  Moreover, the cylindrical inner cylinder 103b and the outer magnetic pole part 103a are also required as the shape of the stator, and it is difficult to manufacture them integrally in terms of component manufacture. Furthermore, when they are assembled separately after being manufactured separately, the number of parts increases, leading to an increase in cost.

  Further, in order to reduce the distance between the outer magnetic pole portion 103a and the auxiliary stator 104, there is a drawback that it is difficult in terms of mechanical strength to reduce the radial thickness of the cylindrical magnet 101.

  In order to solve the above problems, the invention described in claim 1 is directed to a cylindrical magnet having an outer peripheral surface divided into two in the circumferential direction and magnetized to different poles, and a soft magnet fixed to the inner diameter portion of the magnet. A rotor shaft made of a magnetic material, a first outer magnetic pole portion disposed at a predetermined angle with respect to the outer peripheral surface of the magnet, and a shaft of the rotor shaft; A first coil disposed adjacent to the magnet in a direction and wound around the first outer magnetic pole portion to excite the first outer magnetic pole portion; and A second outer magnetic pole portion disposed so as to be 180 degrees out of phase with respect to the center of the magnet and to have a predetermined gap with respect to the outer peripheral surface of the magnet and to face the outer peripheral surface at a predetermined angle; In the axial direction of the rotor shaft The second outer magnetic pole is disposed adjacent to the gnet and arranged on the plane perpendicular to the axial direction of the rotor shaft so as to be substantially aligned with the first coil, and is wound around the second outer magnetic pole portion. And a second coil that excites the first and second outer magnetic pole portions, and the second outer magnetic pole portion is excited to opposite poles.

  In the above configuration, the first outer magnetic pole portion and the second outer magnetic pole portion are arranged so that the phase is shifted by 180 degrees with respect to the center of the magnet magnetized with two poles, and the first coil and the second outer magnetic pole portion are arranged. For example, when the two coils are connected in series so that the winding directions of the conductive wires are different, and the first coil 2 and the second coil 3 connected in series are energized, the first outer magnetic pole portion and the second outer The magnetic poles are respectively excited on the opposite poles, and the rotation angle of the magnet is increased, and the first and second outer magnetic poles arranged 180 degrees out of phase when rotating the magnet are equal to each other. So that the rotational balance is improved.

  In addition, by fixing the rotor shaft to the inner diameter part of the magnet, or configuring the first and second outer magnetic pole parts so as to face the outer peripheral surface of the magnet, the drive device can be reduced in size, cost, and cost. Enables output.

  The invention according to claim 2 is the drive device according to claim 1, an output member that operates according to rotation of the magnet that is a component of the drive device, a ground plate that includes an opening, A light amount adjusting member that is driven by a driving device to move forward and backward with respect to the opening of the base plate in conjunction with the output member operating to one or the other position, and changes the amount of light passing through the opening. This is a light quantity adjusting device.

  According to a third aspect of the present invention, there is provided the driving device according to the first aspect, an output member that operates in accordance with rotation of the magnet that is a component of the driving device, and the driving device that is driven by the driving device. The lens driving device includes a lens barrel that moves the lens in the optical axis direction in conjunction with the operation of the output member to one or the other position.

  The present invention provides a driving device, a light amount adjusting device, and a lens driving device capable of stable driving capable of increasing the rotation angle of a driving device and the operating angle of a driven member while achieving downsizing, cost reduction, and high output. Can be provided.

  As shown in Example 1 and Example 2 below.

  1 to 3 are views showing a driving apparatus according to Embodiment 1 of the present invention. Specifically, FIG. 1 is an exploded perspective view of the driving apparatus, FIG. 2 is an assembled state diagram of the driving apparatus, and FIG. 3 is a coil. FIG. 5 is a cross-sectional view taken along a plane that passes through the rotor shaft and is parallel to the axial direction.

  In these drawings, reference numeral 1 denotes a stator made of a soft magnetic material. Each of the first outer magnetic pole portion 1a, the second outer magnetic pole portion 1b, the first outer magnetic pole portion 1a, and the second outer magnetic pole portion 1b. And a fitting hole 1d for rotating and supporting a rotor shaft 6 to be described later. The first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b are formed in a comb-like shape extending in a direction parallel to the rotor shaft 6 described later.

  In the stator 1 according to the first embodiment, a first outer magnetic pole portion 1a and a second outer magnetic pole portion 1b are integrally formed as illustrated. For this reason, the mutual error between the first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b is reduced, and variations in the performance of the drive device due to assembly can be minimized. Further, since the stator 1 has a simple shape, press molding is possible and the cost is low.

  2 is a first coil formed by winding a conductive wire, 3 is a second coil formed by winding a conductive wire, and 4 is a bobbin around which the first coil 2 and the second coil 3 are wound. The first coil 2 is fixed so that the first outer magnetic pole portion 1a is disposed on the inner side (center portion) of the first coil 2 while being wound around the bobbin 4. Then, by energizing the first coil 2, the first outer magnetic pole portion 1a is excited. Similarly, the 2nd coil 3 is fixed so that the 2nd outer side magnetic pole part 1b may be arrange | positioned in the inner side (center part) in the state wound by the bobbin 4. FIG. Then, by energizing the second coil 3, the second outer magnetic pole portion 1b is excited.

  Since the first coil 2 and the second coil 3 are arranged adjacent to each other on the plane of the flat plate portion 1c of the stator 1, the length in the axial direction of the drive device can be shortened. Further, since the first coil 2 and the second coil 3 are connected in series and adjacent to each other, the total number of turns of the coil is increased, and the output is improved while the axial length of the driving device is kept short. Can be achieved. The first coil 2 and the second coil 3 are connected in series and in different winding directions. That is, if the first coil 2 is wound clockwise, the second coil 3 is wound counterclockwise, and when the first coil 2 and the second coil 3 connected in series are energized, The first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b are excited to opposite poles. The bobbin 4 is not provided for each of the first coil 2 and the second coil 3, but can be connected and integrated together to reduce the cost and can be easily wired in series. . Although the first coil 2 and the second coil 3 are connected in series, they may be connected in parallel. When driving at a constant voltage, the output increases in parallel connection, but the current consumption increases. On the other hand, current consumption can be reduced in series connection compared to parallel connection.

  Reference numeral 5 denotes a cylindrical magnet made of a permanent magnet, and the magnet 5 is magnetized in half in the circumferential direction, that is, half each of the S pole and the N pole. Further, the inner peripheral surface of the magnet 5 has a weak magnetization distribution compared to the outer peripheral surface, or is not magnetized at all, or is opposite to the outer peripheral surface, that is, when the outer peripheral surface is an S pole. The inner peripheral surface of the range is one that is magnetized to the N pole. Reference numeral 6 denotes a rotor shaft made of a soft magnetic material, and the outer peripheral surface of the first cylindrical portion 6a of the rotor shaft 6 and the inner peripheral surface 5a of the magnet 5 are closely fixed by adhesion, press fitting, or the like. At that time, one end of the magnet 5 in the axial direction is fixed so as to be flush with the upper surface of the first cylindrical portion 7a (see FIG. 3).

  By fixing the first cylindrical portion 6a of the rotor shaft 6 to the inner peripheral surface 5a of the magnet 5, there is a concern in terms of strength even if the thickness of the cylindrical shape of the magnet 5 in the radial direction is very thin. Absent. Support shaft portions 6c and 6d are formed at both ends of the rotor shaft 6, and are rotatably supported by a fitting hole 1d of the stator 1 and a cover 7 described later. In that case, the 2nd cylindrical part 6b of the rotor shaft | axis 6 is arrange | positioned adjacently between the 1st coil 2 and the 2nd coil 3, as shown in FIG. Further, the rotor shaft 6 is formed with a third cylindrical portion 6e to which a later-described lever 8 is fitted and fixed.

  The first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b are arranged to face the outer peripheral surface of the magnet 5 with a predetermined gap. And the 1st inner side magnetic pole part is formed in the part which opposes the 1st outer side magnetic pole part 1a of the 1st cylindrical part 6a, and the part adjacent to the outer periphery of the 1st coil 2 of the 2nd cylindrical part 6b. . Similarly, a second inner magnetic pole portion is formed at a portion facing the second outer magnetic pole portion 1b of the first cylindrical portion 6a and a portion adjacent to the outer periphery of the second coil 3 of the second cylindrical portion 6b. The

  When the first coil 2 is energized, the first outer magnetic pole portion 1a and the first inner magnetic pole portion are excited, and a magnetic flux crossing the magnet 5 is generated between the magnetic poles. Acts on 5. At that time, the first outer magnetic pole portion 1a and the first inner magnetic pole portion are excited to opposite poles. Similarly, by energizing the second coil 3, the second outer magnetic pole portion 1b and the second inner magnetic pole portion are excited, and a magnetic flux crossing the magnet 5 is generated between the magnetic poles. Acts on the magnet 5. At that time, the second outer magnetic pole portion 1b and the second inner magnetic pole portion are excited to opposite poles.

  Further, since the first coil 2 and the second coil 3 are connected in series and in different winding directions, the first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b are simultaneously and opposite to each other. Excited to the pole. As a result, as shown in FIG. 3, the first magnetic circuit (first magnetic path) formed by the first coil 2, the first outer magnetic pole portion 1a, and the first inner magnetic pole portion, the second The second magnetic circuit (second magnetic path) formed by the coil 3, the second outer magnetic pole portion 1b, and the second inner magnetic pole portion, the first coil 2, the second coil 3, and the first Magnetic circuit of a third magnetic circuit (third magnetic path) formed by the outer magnetic pole portion 1a, the first inner magnetic pole portion, and the second inner magnetic pole portion and the second outer magnetic pole portion 1b. Is configured, and a significant improvement in output can be achieved.

  As described above, the magnet 5 can be extremely thin in the radial direction of the cylindrical shape, and the first columnar portion 6a that forms an inner magnetic pole portion facing the inner peripheral surface of the magnet 5 and the magnet 5 There is no need to provide an air gap between the inner peripheral surface of each other. Therefore, the distance between the first outer magnetic pole part 1a and the first cylindrical part 6a and the distance between the second outer magnetic pole part 1b and the first cylindrical part 6a can be made very small. Therefore, the magnetic resistance of the first magnetic circuit, the second magnetic circuit, and the third magnetic circuit can be reduced, and the output of the driving device can be increased.

  Further, as shown in FIG. 3, since the inner diameter portion of the magnet 5 is filled with the rotor shaft 6, the mechanical strength of the magnet is larger than that proposed in Patent Document 1, and the rotor shaft 6 acts as a so-called back metal that reduces the magnetic resistance between the S pole and N pole appearing on the inner diameter part of the magnet 5, so that the permeance coefficient of the magnetic circuit is set high, so that Even when used, there is little magnetic deterioration due to demagnetization.

  Further, the one proposed in the above-mentioned Patent Document 1 needs to be assembled while maintaining the gap between the outer diameter part and the outer magnetic pole part of the magnet with high accuracy. It is necessary to provide a predetermined gap to the magnet, and if the variation in component accuracy or assembly accuracy is poor, this gap cannot be secured, and defects such as contact of the inner magnetic pole part with the magnet may occur. In contrast, in the first embodiment, it is only necessary to manage the gap only on the outer diameter side of the magnet 5, so that the assembly becomes easy.

  Further, in Patent Document 1, the inner magnetic pole portion must be configured not to contact the portion connecting the magnet and the shaft, thereby sufficiently increasing the axial length of the inner magnetic pole portion and the magnet facing each other. However, in the first embodiment, since the rotor shaft also serves as the inner magnetic pole portion, the axial length where the inner magnetic pole portion and the magnet 5 face each other can be secured sufficiently long. Thus, the first outer magnetic pole portion 1a, the second outer magnetic pole portion 1b, and the magnet 5 can be used effectively, and the output of the driving device can be increased.

  Further, since the first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b are configured in a comb-teeth shape extending in a direction parallel to the rotor shaft 6, the direction perpendicular to the rotor shaft 6 of the drive device Can be minimized. For example, if the outer magnetic pole part is composed of a yoke plate that extends in the radial direction (perpendicular to the axis) of the magnet, the coil is wound in the radial direction. The outermost diameter in the direction perpendicular to is large. On the other hand, the outermost diameter in the direction perpendicular to the axis of the driving device of the first embodiment is such that the magnet 5, the thickness of the first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b, and the first coil 2 And it is almost determined by the winding width of the second coil 3 (see FIG. 3).

  In addition, since the first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b are comb-shaped extending in a direction parallel to the rotor shaft 6, the first coil 2 and the second coil wound around the bobbin 4 The coil 3 and the rotor composed of the magnet 5 and the rotor shaft 6 can all be assembled from one direction (from the upper direction to the lower direction in FIG. 1), and the assembly workability is good.

  A cover 7 is positioned and fixed to the stator 1 and the bobbin 4. Reference numeral 7a denotes a bearing portion provided integrally with the cover 7, and the support shaft portion 6d of the rotor shaft 6 is fitted into the bearing portion 7a so that the rotor shaft 6 is rotated and held. Reference numeral 8 denotes a lever, which is fixed to the magnet 5 and the rotor shaft 6 by adhesion, press fitting, or the like, and can be rotated integrally. At that time, the hole 8a provided in the lever 8 is fitted into the third cylindrical portion 6e of the magnet 5, and the protrusions 8c and 8d (8d not shown) provided in the lever 8 are the grooves 5b and 5c of the magnet 5. By being fitted, the positioning is fixed at a predetermined phase. The lever 8 is provided with a drive pin 8b at one end thereof. The cover 7 has an opening 7b, and the lever 8 extends from the inside of the cover 7 to the outside through the opening 7b. Thereby, the lever 8 acts as an output means in a state of being in close contact with the magnet 5. That is, the axial length of the entire drive device including the output unit is further shortened.

  The bearing portion 7 a of the cover 7 and the fitting hole 1 d of the stator 1 rotate and hold the rotor shaft 6 in a state where the cover 7 is fixed to the stator 1 and the bobbin 4. In this state, as shown in FIG. 3, the magnet 5 fixed to the rotor shaft 6 has a predetermined clearance between the outer peripheral surface of the magnet 5 and the first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b. The lever 8 fixed at one end in the direction maintains a predetermined gap with the back surface of the cover 7, and the other end in the axial direction maintains a predetermined gap with the first coil 2 and the second coil 3. Therefore, the magnet 5 is disposed adjacent to the first coil 2 and the second coil 3 in the axial direction, and the first coil 2 and the second coil 3 are adjacent to each other on a plane perpendicular to the axial direction. Therefore, it is possible to obtain a driving device having a short axial length.

  FIG. 4 is a top view showing the positional relationship between the magnet 5 and the stator 1, and the cover 7 and the lever 8 are omitted for easy understanding from the drive device shown in FIGS. 1 to 3. As can be seen from FIG. 4, the magnet 5 is formed with a magnetized portion magnetized in the S and N poles by dividing the outer peripheral surface into two in the circumferential direction.

  Here, the positional relationship between the magnet 5, the first outer magnetic pole portion 1a, and the second outer magnetic pole portion 1b will be described.

  The first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b are arranged at positions that are 180 degrees out of phase with respect to the rotation center of the magnet 5. Therefore, when the outer peripheral surface magnetized on the S pole of the magnet 5 is opposed to the first outer magnetic pole portion 1a, the outer peripheral surface magnetized on the N pole of the magnet 5 is the second outer magnetic pole portion. When the outer circumferential surface magnetized on the N pole of the magnet 5 is opposed to the first outer magnetic pole portion 1a, the outer circumferential surface magnetized on the S pole of the magnet 5 is the second When the opposing angles of the first outer magnetic pole part 1a and the second outer magnetic pole part 1b to the magnet 5 are the same, the phase ratios are equal.

  The first coil 2 and the second coil 3 have different winding directions and are wired in series. Therefore, when the first coil 2 and the second coil 3 are energized, the first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b are excited to opposite poles. That is, the magnetic force generated by energizing the first coil 2 and the second coil 3 is a force that rotates the magnet 5 in the same direction. Therefore, in the driving device of Patent Document 1, the outer magnetic pole portion is ½ of the number of magnetized magnetic poles (in the embodiment of Patent Document 1, there are two magnets and one outer magnetic pole portion). However, in the driving apparatus of the first embodiment, the magnet can be configured with two poles and two outer magnetic pole portions, so that the rotation angle can be increased and the rotation balance can be increased. Will be good.

  Here, the relationship between the number of poles of the magnet and the rotatable angle will be briefly described. In the driving device of Patent Document 1 and the driving device of the first embodiment, if the number of magnet poles is N, the rotatable angle is about (360 / N) degrees. (Actually, the rotation angle is smaller than the above due to the influence of friction or the load and the load.) Therefore, in the case of a two-pole magnet, in principle it is possible to rotate nearly 180 degrees. Can be rotated by nearly 90 degrees, which is half of that. Therefore, in the drive device of the first embodiment, since the magnet has two poles, the rotation angle can be increased. Note that the setting of the rotation angle when using the drive device is determined in consideration of the necessary torque. In other words, when the same drive device is used, when the rotation angle is set large, the starting torque becomes small, and when the rotation angle is set small, the starting torque becomes large.

  Next, the operation of the driving apparatus according to the first embodiment of the present invention will be described with reference to FIGS.

  In FIG. 4, the first coil 2 and the second coil 3 are energized so that the first outer magnetic pole portion 1a is the N pole, and the first inner magnetic pole portion (the first cylindrical portion 6a and the second cylindrical portion 6b). Of the first outer magnetic pole portion 1a) as the S pole, the second outer magnetic pole portion 1b as the S pole, and the second inner magnetic pole portion (the first cylindrical portion 6a and the second cylindrical portion 6b). 2 is a state of the driving device in which the portion facing the outer magnetic pole portion 1b) is excited to have N poles. The drive pin 8b of the lever 8 that rotates integrally with the magnet 5 comes into contact with one end of a long hole 9b of the base plate 9 described later, and the rotation is stopped in the state shown in FIG. In this state, while the magnet 5 is energized to the first coil 2 and the second coil 3, the center of the first outer magnetic pole portion 1 a coincides with the center of the magnetized portion of the magnet 5 (the center of the S pole). Thus, a clockwise rotational force is generated in the drawing, and the clockwise direction in the drawing is adjusted so that the center of the second outer magnetic pole portion 1b and the center of the magnetized portion of the magnet 5 (the center of the N pole) coincide with each other. A rotational force is generated. Further, when energization of the first coil 2 and the second coil 3 is stopped, the magnet 5 is held at this position by the cogging force generated in the first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b. Is done.

  The direction of energization to the first coil 2 and the second coil 3 is reversed from the state shown in FIG. 4 so that the first outer magnetic pole portion 1a is the S pole, and the first inner magnetic pole portion (first cylindrical portion 6a and A portion of the second cylindrical portion 6b facing the first outer magnetic pole portion 1a is an N pole, a second outer magnetic pole portion 1b is an N pole, and a second inner magnetic pole portion (the first cylindrical portion 6a and the second cylindrical portion 6a). When the portion of the cylindrical portion 6b facing the second outer magnetic pole portion 1b is excited to be the S pole, the magnet 5 rotates counterclockwise. The magnet 5 is stopped from rotating in the state shown in FIG. 5 because the drive pin 8b of the lever 8 that rotates integrally with the other end of a long hole 9b of the base plate 9, which will be described later. In this state, when the magnet 5 is energized to the first coil 2 and the second coil 3, the center of the first outer magnetic pole portion 1a and the center of the magnetized portion of the magnet 5 (the center of the N pole) coincide. Thus, a counterclockwise rotational force is generated in the figure, and the center of the second outer magnetic pole part 1b and the center of the magnetized part of the magnet 5 (the center of the S pole) coincide with each other. Directional rotational force is generated. Further, when energization of the first coil 2 and the second coil 3 is stopped, the magnet 5 is held at this position by the cogging force generated in the first outer magnetic pole portion 1a and the second outer magnetic pole portion 1b. Is done.

  By switching the energization direction to the first coil 2 and the second coil 3 as described above, the magnet 5 reciprocally rotates in the range determined by the stopper (the long hole 9b of the base plate 9) together with the lever 8. It will be.

  FIG. 6 is an exploded perspective view of a shutter device using the driving device M of the present invention.

  In FIG. 6, 9 is a ground plate having an opening 9a formed at the center, and the driving device M is attached to the ground plate 9 by adhesion or the like. At that time, the drive pin 8 b of the lever 8 in the drive device M is inserted into a long hole 9 b provided in the base plate 9. The magnet 5 can rotate from the position where the drive pin 8b of the lever 8 contacts one end of the long hole 9b to the position where it contacts the other end. Further, the base plate 9 is integrally formed with protrusions 9c and 9d that protrude in the same direction as the drive pin 8b.

  Reference numerals 10 and 11 denote blades. A round hole 10 a of the blade 10 is rotatably fitted to the protrusion 9 d of the base plate 9, and a long hole 10 b of the blade 10 is slidably fitted to the drive pin 8 b of the lever 8. Further, the round hole 11 a of the blade 11 is rotatably fitted to the protrusion 9 c of the base plate 9, and the long hole 11 b of the blade 11 is slidably fitted to the drive pin 8 b of the lever 8. Reference numeral 12 denotes a blade retainer having an opening 12a formed at the center, which is fixed to the base plate 9 with the blade 10 and the blade 11 sandwiched between them with a predetermined gap therebetween. Become.

  By rotation of the magnet 5, the blade 10 is rotated around the round hole 10a by pushing the elongated hole 10b to the drive pin 8b of the lever 8, and the blade 11 is rounded by pushing the elongated hole 11b to the drive pin 8b of the lever 8. It rotates around the hole 11a and is configured to control the amount of light passing through the opening 9a of the base plate 9.

  Since the driving device M has a short length in the axial direction, the driving device M can be a shutter device with little protrusion in the optical axis direction that does not interfere with other lenses and structures. In addition, the shutter speed can be increased since the output is small but the output is high.

  In the first embodiment, the driving device is used as an actuator for driving the shutter blades. However, the driving device may be used for other purposes, such as rotating the diaphragm device or the cam cylinder for driving the lens to two positions. It can be used, and is useful as a drive device having the advantages of high output, small outer diameter, and short axial length. More specifically, the drive pin 8b of the lever 8 is connected to a cam cylinder (not shown) that can rotate around the optical axis, and the cam cylinder rotates by rotating the lever 8, and the cam cylinder A lens driving device in which a lens holder to which a lens (not shown) to be fitted is fixed moves in the optical axis direction by rotating the cam cylinder can be obtained.

  FIGS. 7 to 9 are views showing a driving apparatus according to Embodiment 2 of the present invention. Specifically, FIG. 7 is an exploded perspective view of the driving apparatus, FIG. 8 is an assembled state diagram of the driving apparatus, and FIG. FIG. 5 is a cross-sectional view taken along a plane that passes through the rotor shaft and is parallel to the axial direction.

  In these drawings, reference numeral 21 denotes a stator made of a soft magnetic material, and includes a first outer magnetic pole portion 21a, a second outer magnetic pole portion 21b, a first outer magnetic pole portion 21a, and a second outer magnetic pole portion 21b. A flat plate portion 21c that connects each end and a fitting hole 21d that rotatably supports a rotor shaft 26 described later are provided. The first outer magnetic pole portion 21a and the second outer magnetic pole portion 21b are formed in a comb-like shape extending in a direction parallel to the rotor shaft 26 described later.

  In the stator 21 according to the second embodiment, as shown in the figure, the first outer magnetic pole portion 21a and the second outer magnetic pole portion 21b are integrally formed. For this reason, the mutual error between the first outer magnetic pole portion 21a and the second outer magnetic pole portion 21b is reduced, and the variation in the performance of the drive device due to assembly can be minimized. Further, since the stator 21 has a simple shape, press molding is possible and the cost is low.

  22 is a first coil formed by winding a conductive wire, 23 is a second coil formed by winding a conductive wire, and 24 is a bobbin around which the first coil 22 and the second coil 23 are wound. In addition, the first coil 22 is fixed so that the first outer magnetic pole portion 21a is disposed on the inner side (center portion) of the first coil 22 while being wound around the bobbin 24. Then, by energizing the first coil 22, the first outer magnetic pole portion 21a is excited. Similarly, the second coil 23 is fixed so that the second outer magnetic pole portion 21b is disposed on the inner side (center portion) of the second coil 23 while being wound around the bobbin 24. Then, by energizing the second coil 23, the second outer magnetic pole portion 21b is excited.

  Since the first coil 22 and the second coil 23 are arranged adjacent to each other on the plane of the flat plate portion 21c of the stator 21, the axial length of the drive device can be shortened. In addition, since the first coil 22 and the second coil 23 are connected in series and adjacent to each other, the total number of turns of the coil increases, and the output is improved while the axial length of the drive device is kept short. Can be achieved. Further, the first coil 22 and the second coil 23 are connected in series so that the winding directions are different. That is, if the first coil 22 is wound clockwise, the second coil 23 is wound counterclockwise, and when the first coil 22 and the second coil 23 connected in series are energized, The first outer magnetic pole portion 21a and the second outer magnetic pole portion 21b are excited to opposite poles. The bobbin 24 is not provided for each of the first coil 22 and the second coil 23, but can be connected and integrated together so that the cost can be reduced and wiring in series is easy. . Although the first coil 22 and the second coil 23 are connected in series, they may be connected in parallel.

  Reference numeral 25 denotes a cylindrical magnet made of a permanent magnet. The magnet 25 is divided in the circumferential direction into two parts, that is, half of each of the S and N poles. Further, the inner peripheral surface of the magnet 25 has a weak magnetization distribution compared to the outer peripheral surface, or is not magnetized at all, or is opposite to the outer peripheral surface, that is, when the outer peripheral surface is an S pole. The inner peripheral surface of the range is one that is magnetized to the N pole. Reference numeral 26 denotes a rotor shaft made of a soft magnetic material. The outer peripheral surface of the first cylindrical portion 26a of the rotor shaft 26 and the inner peripheral surface 25a of the magnet 25 are closely fixed by adhesion, press fitting, or the like.

  By fixing the first cylindrical portion 26a of the rotor shaft 26 to the inner peripheral surface 25a of the magnet 25, there is a concern in terms of strength even if the thickness of the magnet 25 in the radial direction is very thin. Absent. Support shaft portions 26c and 26d are formed at both ends of the rotor shaft 26, and are rotatably supported by a fitting hole 21d of the stator 21 and a cover 27 described later. In that case, the 2nd cylindrical part 26b of the rotor shaft | axis 26 is arrange | positioned adjacently between the 1st coil 22 and the 2nd coil 23, as shown in FIG. Further, an output shaft portion 26e to which a later-described lever 28 is fitted and fixed is formed at the tip of the rotor shaft 26.

  The first outer magnetic pole portion 21a and the second outer magnetic pole portion 21b are arranged to face the outer peripheral surface of the magnet 25 with a predetermined gap. The first inner magnetic pole portion is formed at a portion of the first cylindrical portion 26a facing the first outer magnetic pole portion 21a and a portion of the second cylindrical portion 26b adjacent to the outer periphery of the first coil 22. . Similarly, a second inner magnetic pole portion is formed at a portion facing the second outer magnetic pole portion 21b of the first cylindrical portion 26a and a portion adjacent to the outer periphery of the second coil 23 of the second cylindrical portion 26b. The

  When the first coil 22 is energized, the first outer magnetic pole portion 21a and the first inner magnetic pole portion are excited, and a magnetic flux crossing the magnet 25 is generated between the magnetic poles. Act on 25. At that time, the first outer magnetic pole portion 21a and the first inner magnetic pole portion are excited to opposite poles. Similarly, when the second coil 23 is energized, the second outer magnetic pole portion 21b and the second inner magnetic pole portion are excited, and a magnetic flux crossing the magnet 25 is generated between the magnetic poles. Acts on the magnet 25. At that time, the second outer magnetic pole portion 21b and the second inner magnetic pole portion are excited to opposite poles.

  Further, since the first coil 22 and the second coil 23 are connected in series and in different winding directions, the first outer magnetic pole part 21a and the second outer magnetic pole part 21b are simultaneously and opposite to each other. Excited. Thus, as shown in FIG. 9, the first magnetic circuit (first magnetic path) formed by the first coil 22, the first outer magnetic pole portion 21a, and the first inner magnetic pole portion, the second The second magnetic circuit (second magnetic path) formed by the coil 23, the second outer magnetic pole portion 21b, and the second inner magnetic pole portion, the first coil 22, the second coil 23, and the first Magnetic circuit of a third magnetic circuit (third magnetic path) formed by the outer magnetic pole portion 21a, the first inner magnetic pole portion, the second inner magnetic pole portion, and the second outer magnetic pole portion 21b. The output is greatly improved.

  As described above, the magnet 25 can be very thin in the radial direction of the cylindrical shape, and is opposed to the inner peripheral surface of the magnet 25 to form a first columnar portion 26 a that forms an inner magnetic pole portion and the magnet 25. There is no need to provide a gap between the inner peripheral surface. Therefore, the distance between the first outer magnetic pole portion 21a and the first cylindrical portion 26a and the distance between the second outer magnetic pole portion 21b and the first cylindrical portion 26a can be made extremely small. Therefore, the magnetic resistance of the first magnetic circuit, the second magnetic circuit, and the third magnetic circuit can be reduced, and the output of the driving device can be increased.

  Further, as shown in FIG. 9, since the inner diameter portion of the magnet 25 is filled with the rotor shaft 26, the mechanical strength of the magnet is larger than that proposed in Patent Document 1, and the rotor shaft 26 acts as a so-called back metal that reduces the magnetic resistance between the S pole and the N pole appearing on the inner diameter part of the magnet 25, so that the permeance coefficient of the magnetic circuit is set high, so that Even when used, there is little magnetic deterioration due to demagnetization.

  Further, the one proposed in the above-mentioned Patent Document 1 needs to be assembled while maintaining the gap between the outer diameter part and the outer magnetic pole part of the magnet with high accuracy. It is necessary to provide a predetermined gap to the magnet, and if the variation in component accuracy or assembly accuracy is poor, this gap cannot be secured, and defects such as contact of the inner magnetic pole part with the magnet may occur. On the other hand, in the second embodiment, since it is only necessary to manage the gap only on the outer diameter side of the magnet 5, the assembly becomes easy.

  Further, in Patent Document 1, the inner magnetic pole portion must be configured not to contact the portion connecting the magnet and the shaft, thereby sufficiently increasing the axial length of the inner magnetic pole portion and the magnet facing each other. However, in the second embodiment, since the rotor shaft also serves as the inner magnetic pole portion, the axial length where the inner magnetic pole portion and the magnet 25 face each other can be secured sufficiently long. Thus, the first outer magnetic pole portion 21a, the second outer magnetic pole portion 21b, and the magnet 25 can be effectively used, and the output of the driving device can be increased.

  Further, since the first outer magnetic pole portion 21a and the second outer magnetic pole portion 21b are configured in a comb-teeth shape extending in a direction parallel to the rotor shaft 26, the direction perpendicular to the rotor shaft 26 of the driving device. Can be minimized. For example, if the outer magnetic pole part is composed of a yoke plate that extends in the radial direction (perpendicular to the axis) of the magnet, the coil is wound in the radial direction. The outermost diameter in the direction perpendicular to is large. On the other hand, the outermost diameter in the direction perpendicular to the axis of the driving device of the second embodiment has the magnet 25, the thickness of the first outer magnetic pole portion 21a and the second outer magnetic pole portion 21b, and the first coil 22 as shown in FIG. And it is almost determined by the winding width of the second coil 23 (see FIG. 9).

  In addition, since the first outer magnetic pole portion 21a and the second outer magnetic pole portion 21b have a comb-teeth shape extending in a direction parallel to the rotor shaft 26, the first coil 22 and the second coil wound around the bobbin 24 The coil 23 and the rotor composed of the magnet 25 and the rotor shaft 26 can all be assembled from one direction (from the upper side to the lower side in FIG. 7), and the assembly workability is good.

  A cover 27 is positioned and fixed to the stator 21 and the bobbin 24. Reference numeral 27a denotes a bearing portion provided integrally with the cover 27, and the support shaft portion 26e of the rotor shaft 26 is fitted into the bearing portion 27a so that the rotor shaft 26 is rotated and held. Reference numeral 28 denotes a lever, and a drive pin 28b is provided at one end thereof. The lever 28 has a hole portion 28a fixed to the output shaft portion 26d of the rotor shaft 26 by press fitting or the like, and can rotate integrally. At this time, the protrusion 28c provided on the lever 28 is fitted into the groove 25b or the groove 25c of the magnet 25, so that the positioning is fixed at a predetermined phase. Further, the cover 27 is provided with elongated holes 27b and 27c, and the protrusion 28c of the lever 28 is inserted into the elongated hole 27b. Thereby, the lever 28 is fixed to the magnet 25, and the protrusion 28c abuts on the end of the elongated hole 27b, thereby serving as a rotation stopper for the magnet 25. That is, the magnet 25 can rotate from the position where the protrusion 28c of the lever 28 contacts one end of the elongated hole 27b to the position where it contacts the other end. Here, the long hole used as the stopper by inserting the protrusion 28c of the lever 28 may be the long hole 27c instead of the long hole 27b. The long hole portion 27c can also be used as an insertion portion for a phase matching jig when the lever 28 is fixed to the magnet 25.

  The stator 21, the first coil 22, the second coil 23, the bobbin 24, the magnet 25, the rotor shaft 26, and the cover 27 can be unitized as a drive device, and the lever 28 can be connected to the drive device unit later. Since it becomes possible to fix to the output shaft part 26d, the design freedom of the lever 28 increases. For example, a gear can be fixed to the output shaft portion 26d, and a shutter blade can be directly fixed. Further, it is possible to fix the drive device to the surface of the ground plate in a state where the output shaft portion 26d is penetrated, and to fix the lever 28 from the back surface of the ground plate to the output shaft portion 26d, thereby reducing the total thickness of the shutter device. Also suitable for.

  The bearing portion 27a of the cover 27 and the fitting hole 21d of the stator 21 hold the rotor shaft 26 in a state where the cover 27 is fixed to the stator 21 and the bobbin 24, and move the rotor shaft 26 in the axial direction. Restrict within a predetermined range. In this state, as shown in FIG. 9, the magnet 25 fixed to the rotor shaft 26 has a predetermined gap between the outer peripheral surface and the first outer magnetic pole portion 21a and the second outer magnetic pole portion 21b. One end in the axial direction of the magnet 25 maintains a predetermined gap with the back surface of the cover 27, and the other end in the axial direction maintains a predetermined gap with the first coil 22 and the second coil 23. Therefore, the magnet 25 is disposed adjacent to the first coil 22 and the second coil 23 in the axial direction, and the first coil 22 and the second coil 23 are adjacent to each other on a plane perpendicular to the axial direction. Therefore, it is possible to obtain a driving device having a short axial length.

  Since the operation of the driving apparatus according to the second embodiment of the present invention is the same as that of the first embodiment, the description thereof is omitted.

  Here, the effects of the first embodiment and the second embodiment will be collectively listed below.

  1) A first outer magnetic pole portion, which has a predetermined gap with respect to the outer peripheral surface of the magnet 1 and is disposed so as to face the outer peripheral surface at a predetermined angle, and the first outer magnetic pole portion are a magnet A second outer magnetic pole portion that is 180 degrees out of phase with respect to the center and has a predetermined gap with respect to the outer peripheral surface of the magnet and is disposed so as to face the outer peripheral surface at a predetermined angle, It is configured to be excited by poles.

  Thus, since the first outer magnetic pole part and the second outer magnetic pole part are arranged 180 degrees out of phase with respect to the center of the magnet, it is compared with the drive device proposed in Patent Document 1. In addition, since the rotation balance is good and the magnet can be composed of two poles, the driving device can have a large rotation angle.

  2) Since the magnetic flux generated by the energization of the first coil and the magnetic flux generated by the energization of the second coil simultaneously act on the magnet, the number of turns as a total of the driving device can be increased without increasing the number of turns of one coil. As a result, a high-output drive device can be provided while the axial length is reduced without increasing the outer diameter.

  3) If the rotor shaft fixed to the inner peripheral surface of the magnet is called an inner magnetic pole portion, the magnetic flux generated by the first coil is generated between the first outer magnetic pole portion and the inner magnetic pole portion facing the outer peripheral surface of the magnet. The magnetic flux generated by the second coil similarly passes between the second outer magnetic pole portion and the inner magnetic pole portion facing the outer peripheral surface of the magnet. Acts effectively on the magnet. At this time, since it is not necessary to provide a gap between the inner magnetic pole portion and the inner peripheral surface of the magnet, the distance between the outer magnetic pole portion and the inner magnetic pole portion is set as compared with the driving device having the above-described conventional Patent Document 1. It is possible to reduce the magnetic resistance, thereby reducing the magnetic resistance and increasing the output of the driving device.

  4) Since the first inner magnetic pole part and the second inner magnetic pole part are constituted by the rotor shaft, the outer magnetic pole part and the inner magnetic pole part proposed in Patent Document 1 are connected or integrally manufactured. Compared with the case where it does, it can manufacture easily and a cost becomes cheap.

  5) The magnet is excellent in strength because the rotor shaft is fixed to the inner diameter portion.

  6) Since the first outer magnetic pole part and the second outer magnetic pole part are made of the same member, it is possible to reduce the error of the mutual position, reduce the number of parts, and provide a simple structure. It can be provided and the cost is reduced.

  7) The first outer magnetic pole portion and the second outer magnetic pole portion are formed in a comb-teeth shape extending in the same direction as the axial direction of the rotor shaft, thereby reducing the size in the direction perpendicular to the axial direction. In addition, the coil can be easily assembled.

  8) A configuration in which the first coil and the second coil are wired in series, or a configuration in which the first coil and the second coil are wired in parallel, the first coil and the second coil are configured. A single circuit for energizing the coil is sufficient, and the cost is reduced.

  9) Since the first coil and the second coil are configured to have different winding directions in the state where they are assembled to the first outer magnetic pole portion and the second outer magnetic pole portion, respectively, By energizing the second coil, the first outer magnetic pole part and the second outer magnetic pole part can be excited to opposite poles.

  As is clear from the above, it is possible to provide a drive device that is small and has a short axial length, can be driven stably at a low cost, with high output and a large rotation angle. In addition, by using the driving device for a light amount adjusting device such as a shutter device or a lens driving device, the operating angle of a shutter blade or a lens barrel can be increased while achieving miniaturization, cost reduction, and high output. Can take.

(Correspondence between Invention and Example)
In the first embodiment, the magnet 6 in FIGS. 1 and 3 to 5 corresponds to the magnet of the present invention, and the rotor shaft 6 in FIGS. 1 to 5 corresponds to the rotor shaft of the present invention. 1 to 5 corresponds to the first coil of the present invention, and the first outer magnetic pole portion 1a of FIGS. 1 to 5 corresponds to the first outer magnetic pole portion of the present invention. 3 to 5 correspond to the second coil of the present invention, and the second outer magnetic pole portion 1b of FIGS. 1 and 3 to 5 corresponds to the second outer magnetic pole portion of the present invention. It corresponds to. 7 and 9 corresponds to the magnet of the present invention, the rotor shaft 26 of FIGS. 7 to 9 corresponds to the rotor shaft of the present invention, and the second embodiment of FIGS. One coil 22 corresponds to the first coil of the present invention, and the first outer magnetic pole portion 21a of FIGS. 7 and 9 corresponds to the first outer magnetic pole portion of the present invention. The second coil 23 corresponds to the second coil of the present invention, and the second outer magnetic pole portion 21b of FIGS. 7 and 9 corresponds to the second outer magnetic pole portion of the present invention.

  The above is the correspondence between each configuration of the first embodiment and the second embodiment and each configuration of the present invention. However, the present invention is not limited to these embodiments, and the functions shown in the claims or the embodiments are not limited. It goes without saying that any configuration may be used as long as the functions it can achieve.

  The present invention can be applied to various devices in which a rotation angle (operation angle) of a driving member driven from one side to the other side is increased and a good rotational balance is desired.

It is a disassembled perspective view of the drive device concerning Example 1 of the present invention. FIG. 2 is an assembly completed state diagram of the drive device of FIG. 1. It is sectional drawing in a surface parallel to the rotor axial direction of the drive device of FIG. It is a top view which shows the phase relationship of the magnet and stator of the drive device of FIG. It is a top view which shows the state which switched the coil electricity supply from the state of FIG. 4, and rotated the magnet. It is a disassembled perspective view of the shutter apparatus using the drive device of FIG. It is a disassembled perspective view of the drive device which concerns on Example 2 of this invention. It is an assembly completion state figure of the drive device of FIG. It is sectional drawing in a surface parallel to the rotor axial direction of the drive device of FIG. It is a disassembled perspective view which shows one structural example of the conventional drive device. It is sectional drawing in a surface parallel to the rotor axial direction of the drive device shown in FIG.

Explanation of symbols

1,21 Stator 1a, 21a First outer magnetic pole portion 1b, 21b Second outer magnetic pole portion 2,22 First coil 3,23 Second coil 4,24 Bobbin 5,25 Magnet 6,26 Rotor Shaft 7, 27 Cover 8, 28 Lever

Claims (3)

A cylindrical magnet whose outer peripheral surface is divided into two in the circumferential direction and magnetized to different poles;
A rotor shaft made of a soft magnetic material fixed to the inner diameter portion of the magnet;
A first outer magnetic pole portion having a predetermined gap with respect to the outer peripheral surface of the magnet and arranged to face the outer peripheral surface at a predetermined angle;
A first coil disposed adjacent to the magnet in the axial direction of the rotor shaft and wound around the first outer magnetic pole portion to excite the first outer magnetic pole portion;
The first outer magnetic pole portion is 180 degrees out of phase with the center of the magnet, has a predetermined gap with respect to the outer peripheral surface of the magnet, and is arranged to face the outer peripheral surface at a predetermined angle. A second outer magnetic pole portion,
The magnet is disposed adjacent to the magnet in the axial direction of the rotor shaft and substantially aligned with the first coil on a plane perpendicular to the axial direction of the rotor shaft, and is wound around the second outer magnetic pole portion. And a second coil for exciting the second outer magnetic pole part,
A driving apparatus characterized in that the first outer magnetic pole part and the second outer magnetic pole part are excited to opposite poles. A drive device according to claim 1;
An output member that operates in accordance with rotation of the magnet, which is a component of the driving device;
A main plate with an opening;
A light amount adjusting member that is driven by the drive device and moves forward and backward with respect to the opening of the base plate in conjunction with the output member operating to one or the other position, and changes the amount of light passing through the opening. A light amount adjusting device. A drive device according to claim 1;
An output member that operates in accordance with rotation of the magnet, which is a component of the driving device;
A lens driving device comprising: a lens barrel that is driven by the driving device and moves the lens in the optical axis direction in conjunction with the output member operating to one or the other position.

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