WO2017104460A1

WO2017104460A1 - Motor actuator

Info

Publication number: WO2017104460A1
Application number: PCT/JP2016/086032
Authority: WO
Inventors: 久剛有賀
Original assignee: 日本電産サンキョー株式会社
Priority date: 2015-12-16
Filing date: 2016-12-05
Publication date: 2017-06-22
Also published as: JP6894186B2; CN108352733A; JP2017112735A

Abstract

Provided is a motor actuator in which both motor start-up failure and rotor vibration can be suppressed. Specifically, this motor actuator has a motor 10 that is formed from an AC synchronous motor, and a transmission mechanism that transmits the output from the motor 10, wherein the motor 10 has: a rotor 15 provided with a magnet 14 in which the S poles and the N poles are alternately provided in the circumferential direction; and a stator core 12 provided with a plurality of teeth 18, each radially facing the magnet 14. The plurality of teeth 18 include a plurality of main poles 18a arranged in the circumferential direction and interpoles 18b arranged between the circumferentially adjacent main poles 18a. The width dimension Wb of each interpole 18b is wider than one-half of the width dimension Wa of each main pole 18a but narrower than three-fourths of the width dimension Wa of each main pole 18a.

Description

Motor actuator

The present invention relates to a motor actuator provided with a motor and a transmission mechanism.

The actuator that drives the drain valve of the washing machine and the shutter of the ventilation fan is configured as a motor actuator that transmits the rotation of the AC synchronous motor by a transmission mechanism. The AC synchronous motor includes a rotor including a magnet in which S poles and N poles are alternately provided in the circumferential direction, and a stator core including a plurality of teeth facing the magnet in the radial direction. Here, if teeth of the same shape are arranged at equal angular intervals in the circumferential direction, the magnetic poles of the rotor and the teeth are completely opposed when the motor is stopped, and no rotational torque is generated when the motor is started. It becomes defective.

On the other hand, as a plurality of teeth, a plurality of main poles are provided in the circumferential direction, and an auxiliary pole having a dimension in the circumferential direction (width dimension) of less than ½ times that of the main pole is provided between adjacent main poles in the circumferential direction. The arrangement | positioning structure is disclosed (refer patent document 1). According to such a configuration, the state in which the magnetic poles of the rotor and the teeth are completely opposed to each other can be eliminated by supplementary poles. Therefore, rotational torque can be generated at the time of starting the motor, so that starting failure is unlikely to occur. .

Specifically, as shown in FIG. 9A, the number of magnetic poles of the rotor 15 is 8 poles in total including the N pole and the S pole, and the width dimension Wb of the auxiliary pole 18b is less than ½ times the main pole 18a. When the magnetic field analysis is performed when no excitation is applied and when a constant current of 10 mA to 40 mA is applied, the result shown in FIG. 9B is obtained. As can be seen from FIG. 9B, a stable point O11 appears at an angular position of 17.5 ° in the rotational angle of the rotor 15, and an unstable point O12 appears at an angular position of 38.75 ° in the rotational angle of the rotor 15. To do.

JP 2002-262491 A

However, when the width dimension Wb of the auxiliary pole 18b is less than ½ times the main pole 18a as in the configuration described in Patent Document 1, the detent torque is large, so that the magnetic pole of the rotor 15 is between the teeth 18. There is a problem that torque fluctuations due to the attraction and repulsion of the magnetic poles when jumping are large, and the rotor 15 vibrates.

Therefore, as shown in FIG. 10 (a), for example, the width dimension Wb of the auxiliary pole 18b was examined to be expanded to a dimension exceeding 3/4 times the main pole 18a. When the magnetic field analysis is performed when such a configuration is adopted, the result shown in FIG. 10B is obtained. As can be seen from FIG. 10B, a stable point O21 appears at an angular position of 9.075 ° in the rotational angle of the rotor 15, and an unstable point O22 appears at an angular position of 20.45 ° in the rotational angle of the rotor 15. did. Further, the angular position (dead point D20) at which the torque does not change when excited is deviated by only 2 ° from the stable point O21. Moreover, when the width dimension Wb of the auxiliary pole 18b is set to a dimension exceeding 3/4 times the main pole 18a, the detent torque is small. For this reason, if a load is applied to the rotor 15 from the outside when the motor is stopped, the rotor 15 may stop at the dead point D20. Accordingly, when a load is applied to the rotor 15 by an external force or an internal resistance and the torque and the load are balanced, the motor cannot be started.

It should be noted that the rotation angle of the rotor 15 corresponds to an electrical angle × (45/180). The stable point is a position at which the teeth 18 and the magnetic poles of the rotor 15 are completely opposed to each other and is very stable. Therefore, if the external force applied to the rotor 15 is zero, the rotor 15 is always Stop at this place. The unstable point is a position deviated by 1/2 pitch from the stable point and is a very unstable state. Therefore, when an external force is applied to the rotor 15 even a little, the rotor 15 is either clockwise or counterclockwise. Move to the stable point. The dead point is the position of the rotor 15 where no torque change occurs regardless of the increase or decrease of the magnetic force during teeth excitation.

In view of the above problems, an object of the present invention is to provide a motor actuator that can suppress both a motor start failure and a rotor vibration.

In order to solve the above problems, the present invention provides a motor actuator having an AC synchronous motor and a transmission mechanism for transmitting the output of the AC synchronous motor, wherein the AC synchronous motor has an S pole in the circumferential direction. And a stator core having a plurality of teeth opposed to the magnet in the radial direction, and the plurality of teeth are arranged in the circumferential direction. A plurality of main poles and an auxiliary pole disposed between the main poles adjacent in the circumferential direction and having a width dimension that is a dimension in the circumferential direction smaller than the main pole, and the width dimension of the auxiliary pole Is wider than ½ times the width dimension of the main pole and narrower than 3/4 times the width dimension of the main pole.

In the present invention, since the width dimension of the auxiliary pole is narrower than 3/4 times the width dimension of the main pole, the stable point and the dead point can be sufficiently separated. Therefore, the motor can be started properly. In addition, since the width of the auxiliary pole is wider than half the width of the main pole, fluctuations in torque due to magnetic attraction and repulsion when the rotor magnetic pole jumps between the teeth can be suppressed. The vibration of the rotor can be suppressed. Therefore, according to the present invention, it is possible to suppress both startup failure and rotor vibration.

In the present invention, the auxiliary pole is located between the main poles adjacent in the circumferential direction and the main pole located on the opposite side to the rotation direction of the rotor is located on the rotation direction side of the rotor. It is preferable that the distance from the main electrode is narrower. According to such a configuration, it is possible to suppress fluctuations in torque caused by the attraction and repulsion of the magnetic poles when the magnetic poles of the rotor jump over the teeth, so that vibrations of the rotor can be suppressed. Therefore, stability when the rotor rotates can be enhanced.

In the present invention, it is preferable that the complementary poles are evenly arranged and point-symmetrically about the rotation center axis. According to such a configuration, the magnetic balance between the rotor and the stator is good.

In the present invention, it is possible to adopt a mode in which the complementary poles are arranged at two point-symmetrical positions around the rotation center axis. According to such a configuration, since the minimum number of supplementary poles necessary for suppressing start-up failure is provided, it is possible to suppress fluctuations in torque caused by the magnetic pole attracting and repelling when the magnetic pole of the rotor jumps between the teeth. Therefore, vibration of the rotor can be suppressed. In the present invention, it is preferable that the main poles are arranged at six places, and the complementary poles are arranged at every three main poles arranged continuously at equal intervals in the circumferential direction.

The present invention is effective when applied to a case where the transmission mechanism includes a mechanism for applying a load for rotating the rotor during a period in which energization of the motor is stopped. If the transmission mechanism includes a mechanism that applies a load that rotates the rotor while the motor is de-energized, the rotor cannot withstand the load when it approaches the dead point during startup. It is easy to cause problems such as defects, and problems that start-up defects occur when a rotor that has stopped at a stable point rotates to a dead point due to a load.According to the present invention, the occurrence of such problems is suppressed. can do. Further, in the present invention, the transmission mechanism includes a first transmission mechanism that transmits the power of the motor to a mechanism that applies the load, and a clutch unit that switches the power of the first transmission mechanism to a connected state or a disconnected state. And a second transmission mechanism for transmitting the power of the motor to the clutch means. Furthermore, in the present invention, it is preferable that the mechanism for applying the load is a valve body that opens and closes a drain port of the washing machine.

It is explanatory drawing which shows the motive power system in the motor actuator to which this invention is applied. It is a perspective view which shows the principal part of the motor actuator to which this invention is applied. It is a disassembled perspective view of the principal part of the motor actuator to which this invention is applied. It is a disassembled perspective view of the clutch means shown in FIG. It is explanatory drawing of the clutch pinion and motor pinion in the motor actuator to which this invention is applied. It is explanatory drawing of the lock lever etc. which are arrange | positioned under the driven side gearwheel shown in FIG. It is a disassembled perspective view of the motor used for the motor actuator to which this invention is applied. It is explanatory drawing of the teeth of the motor of the motor actuator to which this invention is applied. It is explanatory drawing of the teeth of the motor which concerns on the comparative example of this invention. It is explanatory drawing of the teeth of the motor which concerns on another comparative example of this invention.

Hereinafter, embodiments of the present invention will be described in detail. In the following description, “upper and lower” means the upper and lower in FIG. The “original position” refers to the position of each constituent member in a state where the motor 10 is not driven.

(Overall configuration of motor actuator 1)
FIG. 1 is an explanatory diagram showing a power system in a motor actuator 1 to which the present invention is applied. As shown in FIG. 1, the power system of the motor actuator 1 includes a first transmission mechanism 2 that transmits the power of the motor 10 to the driven member 90 and a second transmission mechanism 3 that operates the clutch means 30. The clutch means 30 switches the transmission of power by the first transmission mechanism 2 to a connected state or a disconnected state. If the clutch means 30 is in the joint state, the power of the motor 10 is transmitted to the driven member 90. If the clutch means 30 is in the disconnected state, the power of the motor 10 is not transmitted to the driven member 90. In this embodiment, a part of the power of the motor 10 is used as the power for operating the clutch means 30.

(Specific configuration example of the motor actuator 1)
FIG. 2 is a perspective view showing a main part of the motor actuator 1 to which the present invention is applied. FIG. 3 is an exploded perspective view of a main part of the motor actuator 1 to which the present invention is applied. FIG. 4 is an exploded perspective view of the clutch means 30 shown in FIG. FIG. 5 is an explanatory diagram of the clutch pinion 21 and the motor pinion 41 in the motor actuator 1 to which the present invention is applied. FIG. 6 is an explanatory diagram of the lock lever 44 and the like disposed below the driven gear 43 shown in FIG.

As shown in FIG. 2 and FIG. 3, the motor actuator 1 includes a motor 10 that is a drive source, a first transmission mechanism 2 that transmits power of the motor 10 to the driven member 90, and power of the first transmission mechanism 2. The clutch means 30 that switches the transmission to the connected state or the disconnected state, the second transmission mechanism 3 that transmits the power of the motor 10 to the clutch means 30, and the load applying means 50 that applies a load to the driven gear 43 are provided. The motor 10, the first transmission mechanism 2, the clutch means 30, the second transmission mechanism 3, and the load applying means 50 are all housed in a case (not shown). The motor 10 is an AC synchronous motor, and the detailed configuration of the motor 10 will be described later with reference to FIG.

(First transmission mechanism 2)
FIG. 4 is an exploded perspective view of the clutch means 30 shown in FIG. FIG. 5 is an explanatory diagram of the clutch pinion 21 and the motor pinion 41 in the motor actuator 1 to which the present invention is applied. FIG. 6 is an explanatory diagram of the lock lever 44 and the like disposed below the driven gear 43 shown in FIG. The 1st transmission mechanism 2 comprises the output system which transmits the motive power of the motor 10 to the driven member 90 (refer FIG. 3). The first transmission mechanism 2 includes a clutch pinion 21, an input side gear 22 meshing with the clutch pinion 21, and an output side gear 23 that rotates with the rotation of the input side gear 22 when the clutch means 30 is in the connected state (see FIG. 4), a composite gear 24 that meshes with the output gear 23, a cam gear 25 that meshes with the composite gear 24, and a pulley 26 that rotates integrally with the cam gear 25. A wire 27 (see FIG. 3) to which a driven member 90 is connected is wound around the pulley 26. The input side gear 22 and the output side gear 23 constitute the clutch means 30.

The clutch pinion 21 is a spur gear supported on the support shaft 150 of the motor 10 so as to be rotatable and movable in the axial direction. A locked projection 211 is formed on the upper surface of the clutch pinion 21. The sector lever 60 acts on the locked projection 211. The clutch pinion 21 is biased upward by a coil spring (not shown). An upper engaging portion 215 (see FIG. 5) that engages with the motor pinion 41 is formed on the lower surface of the clutch pinion 21.

The input side gear 22 meshes with the clutch pinion 21. The input side gear 22 is a sun gear that constitutes a planetary gear mechanism. The input-side gear 22 includes a large-diameter large-diameter gear 221 and a small-diameter gear (not shown) formed smaller in diameter than the large-diameter gear 221 inside the large-diameter gear 221. The large-diameter gear 221 meshes with the clutch pinion 21, and the input-side gear 22 rotates as the clutch pinion 21 rotates.

The power of the motor 10 is transmitted to the output side gear 23 via the clutch pinion 21 and the input side gear 22. As shown in FIG. 4, the output side gear 23 includes three planetary gears 231 and a planetary support gear 232 that rotatably supports the planetary gear 231, and the planetary gear 231 is an upper end surface of the planetary support gear 232. And the retaining ring 233 are provided at equiangular intervals. The planetary support gear 232 has a gear portion 2321 on the side opposite to the side that supports the planetary gear 231. The planetary gear 231 meshes with the small-diameter gear of the input-side gear 22 and revolves around the small-diameter gear of the input-side gear 22 when the clutch means 30 is in the joint state. Further, when the planetary gear 231 revolves, the planetary support gear 232 rotates and power is transmitted from the input side gear 22 to the output side gear 23.

2 and 3 again, the compound gear 24 is engaged with the planetary support gear 232. The compound gear 24 includes a small-diameter gear 241 and a large-diameter gear 242 having a larger diameter than the small-diameter gear 241, and the large-diameter gear 242 meshes with the gear portion 2321 of the planetary support gear 232. Therefore, when the planetary support gear 232 rotates, the compound gear 24 rotates.

The gear portion 251 of the cam gear 25 meshes with the small diameter gear 241 of the compound gear 24. Therefore, when the compound gear 24 rotates, the cam gear 25 rotates. In the cam gear 25, a cam groove 252 is formed on the upper end surface of the disc portion where the gear portion 251 is formed. A fan-shaped lever 60 described later is engaged with the cam groove 252.

The pulley 26 is fixed to the cam gear 25 by a bolt 269. Accordingly, when the cam gear 25 rotates, the pulley 26 rotates. One end of a wire 27 is fixed to the pulley 26. Therefore, when the pulley 26 rotates in the direction in which the wire 27 is drawn, the wire 27 is wound around the pulley 26. A driven member 90 (for example, a valve body that opens and closes a drain port) is fixed to the other end side of the wire 27, and the driven member 90 is always in its original position (valve body as indicated by an arrow F). The load in the direction (the direction in which the wire 27 is pulled out) to return to the position where the is closed) is acting.

(Clutch means 30)
The operation of the clutch means 30 shown in FIG. 4 uses a planetary gear mechanism including an input side gear 22 (sun gear), an output side gear 23 (planetary gear 231 and planetary support gear 232), and a fixed gear 31 (ring gear). It is a thing. In the clutch means 30, a fixed gear 31 is disposed between the input side gear 22 and the planetary support gear 232, and the fixed gear 31 has an external gear 311 and an internal gear 312. Three planetary gears 231 mesh with the internal gear 312 of the fixed gear 31. The external gear 311 of the fixed gear 31 is positioned below the large-diameter gear 221 of the input side gear 22 and meshes with a lock gear 46 described later. For this reason, when the rotation of the lock gear 46 is blocked, the rotation of the fixed gear 31 is blocked.

In the clutch means 30, whether the planetary gear 231 revolves and the planetary support gear 232 rotates depends on whether the rotation of the fixed gear 31 is blocked. That is, when the input side gear 22 rotates while the rotation of the fixed gear 31 is blocked, the planetary gear 231 revolves along the internal gear 312 and the planetary support gear 232 rotates. On the other hand, even if the input side gear 22 rotates when the rotation of the fixed gear 31 is not blocked and the planetary gear 231 tries to revolve, the fixed gear 31 rotates idly, so that the planetary support gear 232 does not rotate. Therefore, if the rotation of the fixed gear 31 is blocked, the first transmission mechanism 2 is brought into a joint state by the clutch means 30, and if the rotation of the fixed gear 31 is not blocked, the first transmission is performed by the clutch means 30. The mechanism 2 is disconnected.

(Second transmission mechanism 3)
The second transmission mechanism 3 constitutes a clutch operating system that transmits the power of the motor 10 to the clutch means 30. The second transmission mechanism 3 includes a motor pinion 41, a driving gear 42 that meshes with the motor pinion 41, a driven gear 43 that meshes with the driving gear 42, and a lock lever 44 that is pushed down when the driven gear 43 moves downward. (See FIG. 6), and a lock gear 46 that is locked when the lock lever 44 is pushed down. The motor pinion 41 is a spur gear formed integrally with the rotor 15 of the motor 10. On the upper surface of the motor pinion 41, a lower engagement portion 415 (see FIG. 5) that engages with the upper engagement portion 215 formed on the lower surface of the clutch pinion 21 is formed. Therefore, when the clutch pinion 21 is positioned at the lowermost position by the inclined cam of the sector lever 60 described later and the upper engagement portion 215 of the clutch pinion 21 and the lower engagement portion 415 of the motor pinion 41 are engaged, the clutch pinion 21 And the motor pinion 41 rotate integrally. That is, the power of the motor 10 is also transmitted to the clutch pinion 21.

The drive side gear 42 meshes with the motor pinion 41. The driving gear 42 is supported by the support shaft 427 so as to be rotatable and movable in the axial direction. The driving gear 42 includes a large-diameter gear 421 and a small-diameter gear 422 having a smaller diameter than the large-diameter gear 421. The small-diameter gear 422 has helical teeth. The drive side gear 42 has a large diameter gear 421 meshing with the motor pinion 41.

The driven side gear 43 meshes with the driving side gear 42, and the driven side gear 43 is rotatably supported by the support shaft 437. The driven gear 43 includes a large diameter gear 432 and a small diameter gear 431 having a smaller diameter than the large diameter gear 432. Both the large diameter gear 432 and the small diameter gear 431 are formed with helical teeth. In the driven gear 43, the large diameter gear 432 is engaged with the small diameter gear 422 of the drive side gear 42. Therefore, the driven gear 43 rotates as the driving gear 42 rotates. At that time, a downward thrust load is generated on the driven gear 43 because a load in the direction opposite to the rotation direction is applied by the load applying means 50 described later. Therefore, when the drive side gear 42 rotates, the driven side gear 43 moves downward while rotating.

As shown in FIG. 6, the lock lever 44 is a flat plate-like member, and is supported by a support shaft 437 so as to be movable in the axial direction below the driven gear 43. A concave portion 442 is formed at one end of the lock lever 44, and the concave portion 442 is engaged with a convex portion (not shown) extending in the axial direction in a case (not shown). For this reason, the lock lever 44 is prevented from rotating. A convex lock portion 441 is formed at the other end of the lock lever 44. A biasing member (not shown) for biasing the lock lever 44 upward is disposed below the lock lever 44. When the motor 10 is stopped by the biasing member, the lock lever 44 is It is located above the locked portion 461 of the lock gear 46. Further, since the driven gear 43 is disposed on the lock lever 44, the driven gear 43 is also biased upward. Here, the urging force of the urging member is smaller than the downward thrust load generated in the driven gear 43 when the driven gear 43 rotates as the driving gear 42 rotates. Therefore, when the driven gear 43 rotates, the driven gear 43 moves downward against the biasing force of the biasing member. As a result, the lock lever 44 also moves downward, so that the lock portion 441 of the lock lever 44 moves to substantially the same height as the locked portion 461 of the lock gear 46.

The lock gear 46 includes a disc portion 463 and a gear 462 formed above the disc portion 463, and the locked portion 461 protrudes outward from the disc portion 463. Therefore, when the lock lever 44 moves downward, the lock portion 441 and the locked portion 461 interfere with each other, and the rotation of the lock gear 46 is prevented. On the other hand, the lock gear 46 meshes with the external gear 311 of the fixed gear 31. Therefore, when the rotation of the lock gear 46 is blocked, the rotation of the fixed gear 31 is also blocked. In this embodiment, the lock gear 46 has a brake portion 464 that is a centrifugal brake. The brake unit 464 applies a load in a direction that hinders the rotation of the lock gear 46, and prevents the lock gear 46 from rotating at a higher speed than necessary.

(Load applying means 50)
The load applying means 50 is configured to apply a load in the direction opposite to the rotation direction to the driven gear 43, and includes a gear 51 made of a worm gear and a load portion 52 made of a centrifugal brake. The gear 51 extends in a direction orthogonal to the axial direction of the driven gear 43 and meshes with the large-diameter gear 432. The large-diameter gear 432 and the gear 51 constitute a speed increasing gear mechanism. Accordingly, the rotation of the driven gear 43 is increased and transmitted to the gear 51. The load unit 52 is a governor that increases the load generated in the direction of stopping the rotation when the rotation speed increases.

When the rotational speed of the driven gear 43 is increased by the load portion 52, the load received in the direction to stop the rotation increases. As the load of the load portion 52 increases, the driven gear 43 that meshes with the driving gear 42 receives the downward thrust load. Further, the driven gear 43 receives a downward thrust load also by the meshing of the large diameter gear 432 and the gear 51. At this time, when the downward thrust load received by the driven gear 43 becomes larger than the upward biasing force of the biasing member, the driven gear 43 is subjected to a load in the direction opposite to the rotation direction by the load portion 52. It moves downward by meshing.

(Configuration of sector lever 60 etc.)
2 and 3 again, the sector lever 60 is disposed on the compound gear 24. The sector lever 60 is rotatably supported by the support shaft 247 as in the compound gear 24. An engaging protrusion 61 is formed on the lower surface of the sector lever 60. The engaging protrusion 61 is engaged with a cam groove 252 formed on the upper surface of the cam gear 25. Although not shown, a lock protrusion and an inclined cam are formed on the lower surface of the sector lever 60. Accordingly, when the pulley 26 winds the wire 27 to a predetermined position, when the sector lever 60 rotates to the predetermined position, the lock protrusion acts on the locked protrusion 211 of the clutch pinion 21 in conjunction with the operation of the cam gear 25, and the clutch pinion 21 is prevented from rotating. At the same time, the clutch pinion 21 pressed downward by the inclined cam is released and moved upward by the coil spring. As a result, the engagement between the upper engagement portion 215 of the clutch pinion 21 and the lower engagement portion 415 of the motor pinion 41 is released. That is, the power of the motor 10 is not transmitted to the clutch pinion 21.

(Operation of motor actuator 1)
In the motor actuator 1, a power transmission operation for transmitting the power of the motor 10 to the driven member 90 in the original position and a power cutoff operation for interrupting the transmission of the power of the motor 10 and returning the driven member 90 to the original position. Done.

(Power transmission operation)
In the power transmission operation, when the motor 10 is driven in one direction with the driven member 90 in the original position (the wire 27 is not wound around the pulley 26), the motor pinion 41 and the clutch pinion 21 are integrally integrated. And the driven gear 43 rotates. Since the gear 51 is meshed with the large-diameter gear 432 of the driven gear 43, a load is generated in a direction in which the rotation is stopped when the rotation speed increases, and the load is applied to the driven gear 43. Is done. Here, the transmission of power between the drive side gear 42 and the driven side gear 43 is due to the meshing of the helical teeth. Therefore, the driven gear 43 receives a downward thrust load due to the rotation of the driving gear 42, and the driven gear 43 moves downward while rotating. Further, since the meshing between the driven gear 43 and the gear 51 is also due to the helical teeth, a large downward thrust load is generated in the driven gear 43. As a result, the lock lever 44 moves downward, so that the rotation of the lock gear 46 is prevented. Therefore, since the rotation of the fixed gear 31 is also prevented, the transmission of power by the first transmission mechanism 2 is brought into a joint state by the clutch means 30.

Therefore, when the clutch pinion 21 is rotated together with the motor pinion 41 by driving the motor 10, the input side gear 22 is rotated and the planetary gear 231 is revolved, so that the planetary support gear 232 is rotated. Therefore, the rotational power of the input side gear 22 is transmitted to the output side gear 23. Here, the large-diameter gear 242 of the compound gear 24 meshes with the gear portion 2321 of the planetary support gear 232. Therefore, the compound gear 24 rotates as the planetary support gear 232 rotates. Further, the gear portion 251 of the cam gear 25 is meshed with the small diameter gear 241 of the compound gear 24. Therefore, the cam gear 25 rotates as the compound gear 24 rotates. When the cam gear 25 rotates, the pulley 26 fixed to the upper end of the cam gear 25 rotates. When the pulley 26 rotates, the wire 27 fixed to the pulley 26 is wound up along the wire groove 261. Since the driven member 90 is fixed to the tip of the wire 27, the driven member 90 operates to be pulled up by the wire 27. For example, when the driven member 90 is a valve body that opens and closes the drain port of the washing machine, the drain port is opened when the valve body is pulled up by the wire 27, and drainage is started.

The winding of the wire 27 by the pulley 26 is stopped as follows. First, when the cam gear 25 rotates to a predetermined position, the sector lever 60 having the engaging protrusion 61 that engages with the cam groove 252 rotates in a direction away from the cam gear 25. As a result, the locking projection of the sector lever 60 contacts the locked projection 211 of the clutch pinion 21 from the circumferential direction. As a result, the clutch pinion 21 is prevented from rotating. Further, the clutch pinion 21 pressed downward in the axial direction by the inclined cam of the sector lever 60 is released and moves upward. As a result, the upper engagement portion 215 of the clutch pinion 21 and the lower engagement portion 415 of the motor pinion 41 are disengaged, and the power of the motor 10 is not transmitted to the clutch pinion 21. As a result, the winding of the wire 27 by the pulley 26 is stopped and the pulley 26 is held at the winding position (when the driven member 90 is a valve body that opens and closes the drain of the washing machine, State in which opening is maintained).

(Power cutoff operation)
When returning the driven member 90 to the original position, the energization to the motor 10 is stopped. As a result, since the rotation of the motor pinion 41 and the drive side gear 42 stops, the rotation of the driven side gear 43 also stops. When the rotation of the driven gear 43 stops, the downward thrust load on the driven gear 43 disappears. Here, since the driven gear 43 is biased upward by the biasing member together with the lock lever 44, when the thrust load disappears, the driven gear 43 moves upward while rotating and returns to the original position. At that time, the lock lever 44 also moves upward and returns to the original position. When the lock lever 44 moves upward, the height direction position of the lock portion 441 of the lock lever 44 becomes higher than the height direction position of the locked portion 461 of the lock gear 46. Therefore, the state in which the rotation of the lock gear 46 is prevented is eliminated, and the lock gear 46 can freely rotate. Accordingly, the fixed gear 31 of the clutch means 30 can be freely rotated, and the clutch means 30 is disconnected. Here, the driven member 90 is always going to return to the original position by an external load acting on itself. For example, when the driven member 90 is a valve body that opens and closes the drain port of the washing machine, and the valve body is operated in a direction to open the drain port by driving the motor actuator 1, the valve body always opens the drain port. It is biased in the closing direction. Therefore, when the clutch means 30 is in the disconnected state, the load applied to the driven member 90 is transmitted to the planetary support gear 232 of the output side gear 23 so as to reverse the first transmission mechanism 2. The energy based on the load applied to the driven member 90 thus transmitted is consumed by idling of the output side gear 23 because the clutch means 30 is in the disengaged state. Thereby, the driven member 90 returns to the original position.

Further, when the cam gear 25 returns to the original position, the sector lever 60 having the engagement protrusion 61 that engages with the cam groove 252 rotates in a direction approaching the cam gear 25. When the sector lever 60 rotates in this way, the locking projection 62 of the sector lever 60 is separated from the locked projection 211 of the clutch pinion 21. As a result, the clutch pinion 21 is allowed to rotate. Further, the clutch pinion 21 urged upward in the axial direction by the coil spring is pressed against the inclined cam and moves downward. Accordingly, the upper engagement portion 215 of the clutch pinion 21 and the lower engagement portion 415 of the motor pinion 41 are engaged, and the power of the motor 10 is transmitted to the clutch pinion 21.

At that time, the brake portion 464 of the lock gear 46 brakes the operation of the driven member 90 to return to the original position, and softens the impact applied to the first transmission mechanism 2. Therefore, damage to the power transmission member constituting the first transmission mechanism 2 can be prevented. In addition, when the driven member 90 returns to the original position, an impact sound that collides with each other (when the driven member 90 is a valve body that opens and closes the drain port of the washing machine, the valve body is (Impact sound that collides with the surroundings) can be reduced.

(Configuration of motor 10)
FIG. 7 is an exploded perspective view of the motor 10 used in the motor actuator 1 to which the present invention is applied. As shown in FIG. 7, the motor 10 includes a rotor 15 that is rotatably supported by a support shaft 150 and a stator 11, and the rotor 15 includes a cylindrical magnet 14. The stator 11 includes a plate-shaped stator core 12 including a plurality of teeth 18 that face the magnet 14 on the outer side in the radial direction, and an insulator 13 that holds the stator core 12. The teeth 18 are cylindrical in shape of the insulator 13. It is positioned so as to be along the inner peripheral surface of the body portion 130 of the body. The insulator 13 has

flange portions

131 and 132 on both sides of the body portion 130, and the coil wire 19 is wound around the body portion 130 between the

flange portions

131 and 132. The stator 11 thus configured is covered with a cover 16, and the cover 16 and the insulator 13 are connected.

In the motor 10 configured as described above, when the motor 10 is stopped, the rotor 15 tries to stop at a stable point. However, in this embodiment, when the motor 10 is stopped, the upper engagement portion 215 of the clutch pinion 21 shown in FIG. 5 is engaged with the lower engagement portion 415 of the motor pinion 41. Here, since both the upper engaging portion 215 and the lower engaging portion 415 are in contact with each other through the inclined surface, the rotor 15 is pushed by the upper engaging portion 215 of the clutch pinion 21 when the motor 10 is stopped. Depending on the load, there is a risk of rotating to the dead point.

Further, when the motor 10 is stopped, the clutch means 30 is disengaged, but the compound gear 24 is engaged with the motor pinion 41. For this reason, a load is applied to the rotor 15 due to the frictional resistance of the composite gear 24, grease, or the like, and when the motor 10 is stopped, the rotor 15 may not stop at a stable point but may stop at a dead point.

Therefore, in the present embodiment, the stator core 12 is provided with teeth 18 having a configuration described with reference to FIG.

(Configuration of teeth 18)
FIG. 8 is an explanatory diagram of the teeth 18 of the motor 10 of the motor actuator 1 to which the present invention is applied. FIGS. 8A and 8B are plan views of the teeth 18 and an explanation showing the magnetic field analysis result at that time. FIG.

In this embodiment, as shown in FIG. 8 (a), the plurality of teeth 18 include a plurality of main poles 18a arranged in the circumferential direction, and between the main poles 18a adjacent in the circumferential direction. Includes a complementary pole 18b having a width dimension smaller than that of the main pole 18a in the circumferential direction. In this embodiment, the number of magnetic poles of the rotor 15 is 8 poles in total including the N pole and the S pole, and the main pole 18a has three main poles 18a at equal intervals in each of two regions separated in the circumferential direction. Has been placed. On the other hand, the complementary poles 18b are arranged evenly and symmetrically with respect to the rotation center axis L. In this embodiment, the complementary poles 18b are arranged at positions adjacent to each other in the clockwise direction CW in two regions where the three main poles 18a are arranged at equal intervals. They are arranged point-symmetrically around the rotation center axis L. Here, the rotor 15 rotates clockwise CW, and corresponding to this configuration, the auxiliary pole 18b is positioned on the opposite side to the rotation direction of the rotor 15 between the main poles 18a adjacent in the circumferential direction. The distance from the main pole 18a is narrower than the distance from the main pole 18a located on the rotation direction side of the rotor 15. That is, the main poles 18a are arranged at six places, and the auxiliary poles 18b are arranged at every three main poles 18a arranged continuously at equal intervals in the circumferential direction.

When the magnetic field analysis was performed in the case of the motor 10 provided with the auxiliary electrode 18b having such a configuration when no excitation was applied and when a constant current of 10 mA to 40 mA was applied, the result shown in FIG. 8B was obtained. As can be seen from FIG. 8B, the detent torque is smaller than the result shown in FIG. 9B (in the case where the width dimension Wb of the auxiliary pole 18b is less than ½ times the main pole 18a). It is larger than the result shown in (b) (when the width dimension Wb of the auxiliary electrode 18b is 3/4 or more times that of the main electrode 18a). Further, a stable point O31 appears at an angular position of 21.25 ° with respect to the rotational angle of the rotor 15, and an unstable point O32 appears at an angular position of 41.25 ° with respect to the rotational angle of the rotor 15. Further, the angular position (dead point D30) at which the torque does not change when excited is deviated by 15 ° from the stable point O31 by the rotation angle of the rotor 15.

Therefore, even when a load is applied to the rotor 15 when the motor 10 is stopped, it is difficult for the rotor 15 to rotate to the dead point. Further, even when a load is applied to the rotor 15 at the time of start-up, the rotational torque exceeds the load, so that a start-up failure hardly occurs in the motor 10. In this embodiment, since the detent torque is smaller than the result shown in FIG. 9B (when the width dimension Wb of the auxiliary pole 18b is less than ½ times the main pole 18a), the rotor 15 rotates. The torque fluctuation due to the magnetic pole attracting and repelling when the magnetic pole of the rotor 15 jumps between the teeth 18 is not large.

(Main effects of this form)
As described above, in the motor 10 (AC synchronous motor) used in the motor actuator 1 of the present embodiment, the width dimension Wb of the auxiliary pole 18b is wider than ½ times the width dimension Wa of the main pole 18a. Since it is narrower than twice, the detent torque is at an appropriate level. Further, since the width dimension Wb of the auxiliary pole 18b is smaller than 3/4 times the width dimension Wa of the main pole 18a, the stable point O31 and the dead point D30 can be sufficiently separated. Therefore, since the rotor 15 is difficult to stop at the dead point D30, the motor 10 can be started appropriately. Further, since the width dimension Wb of the auxiliary pole 18b is larger than ½ times the width dimension Wa of the main pole 18a, the fluctuation of the torque due to the attraction and repulsion of the magnetic pole when the magnetic pole of the rotor 15 jumps between the teeth 18 Therefore, vibration of the rotor 15 can be suppressed. Therefore, both the starting failure and the vibration of the rotor 15 can be suppressed.

Further, the interval between the auxiliary pole 18 b and the main pole 18 a located on the opposite side of the rotation direction of the rotor 15 (clockwise CW direction) between the main poles 18 a adjacent in the circumferential direction is the rotation of the rotor 15. It is narrower than the distance to the main pole 18a located on the direction (clockwise CW direction) side. For this reason, the fluctuation | variation of the torque resulting from the attraction | suction and repulsion of the magnetic pole when the magnetic pole of the rotor 15 jumps between the teeth 18 can be suppressed. Therefore, since vibration of the rotor 15 can be suppressed, stability when the rotor 15 rotates can be improved.

Further, since the complement poles 18b are arranged evenly and point-symmetrically about the rotation center axis L, the magnetic balance between the rotor 15 and the stator 11 is good. In particular, in this embodiment, the complementary poles 18b are arranged at two point-symmetrical points with the rotation center axis L as the center. For this reason, since the minimum auxiliary pole 18b necessary for suppressing the start-up failure is provided, it is possible to suppress the torque fluctuation caused by the magnetic pole attracting and repelling when the magnetic pole of the rotor 15 jumps between the teeth 18. Therefore, since vibration of the rotor 15 can be suppressed, stability when the rotor 15 rotates can be improved.

8B, in addition to the result shown in FIG. 8B, the width dimension Wb of the auxiliary pole 18b is wider than ½ times the width dimension Wa of the main pole 18a, and narrower than 3/4 times the width dimension Wa of the main pole 18a. Although various conditions were evaluated, as shown in FIG. 8B, all have effects such as the detent torque being at an appropriate level, and both the starting failure and the vibration of the rotor 15 are suppressed. It was confirmed that it was possible.

(Other embodiments)
In the above embodiment, the auxiliary pole 18b is provided at an angular position that is 180 ° apart. For example, the auxiliary pole 18b may be provided at an adjacent position. In the above embodiment, the two complementary poles 18b are provided. However, the complementary poles 18b may be provided at one place or at three or more places.

In the above embodiment, the number of magnetic poles of the rotor 15 is 8 poles including the N pole and the S pole, but the present invention may be applied to other poles.

DESCRIPTION OF SYMBOLS 1 ... Motor actuator, 2 ... 1st transmission mechanism, 3 ... 2nd transmission mechanism, 10 ... Motor, 11 ... Stator, 12 ... Stator core, 14 ... Magnet, 15 ... Rotor, 16 ... Cover, 18 ... Teeth, 18a ... Main Poles, 18b ... complementary poles, 19 ... coil wire, 21 ... clutch pinion, 22 ... input side gear, 23 ... output side gear, 24 ... compound gear, 25 ... cam gear, 30 ... clutch means, 41 ... motor pinion, 42 ... Drive side gear, 43 ... Drive side gear, 44 ... Lock lever, 50 ... Load applying means, 60 ... Fan lever, 90 ... Driven member, 150 ... Support shaft

Claims

AC synchronous motor,
A transmission mechanism for transmitting the output of the AC synchronous motor;
In a motor actuator having
The AC synchronous motor includes a rotor including a magnet in which S poles and N poles are alternately provided in a circumferential direction, and a stator core including a plurality of teeth facing the magnet in a radial direction,
The plurality of teeth are arranged between a plurality of main poles arranged in the circumferential direction and the main poles adjacent to each other in the circumferential direction, and a width dimension that is a dimension in the circumferential direction is smaller than the main pole. And include
The motor actuator according to claim 1, wherein a width dimension of the complementary electrode is larger than ½ times a width dimension of the main pole and smaller than 3/4 times the width dimension of the main pole.
The auxiliary pole is located between the main poles adjacent to each other in the circumferential direction, and the main pole is located at a rotation direction side of the rotor with a distance from the main pole located on the opposite side to the rotation direction of the rotor. The motor actuator according to claim 1, wherein the motor actuator is narrower than the distance of the motor actuator.
3. The motor actuator according to claim 2, wherein the complementary poles are evenly arranged and point-symmetrically about the rotation center axis.
4. The motor actuator according to claim 3, wherein the complementary poles are arranged at two point-symmetrical positions around the rotation center axis.
5. The motor actuator according to claim 4, wherein the main pole is arranged at six places, and the auxiliary pole is arranged at every three main poles arranged continuously at equal intervals in the circumferential direction. .
The motor according to claim 1, wherein the transmission mechanism includes a mechanism that applies a load that rotates the rotor during a period in which energization of the motor is stopped. Actuator.
The transmission mechanism includes: a first transmission mechanism that transmits power of the motor to a mechanism that applies the load; clutch means that switches power from the first transmission mechanism to a connected state or a disconnected state; and The motor actuator according to claim 6, further comprising a second transmission mechanism that transmits the clutch means.
The motor actuator according to claim 6, wherein the mechanism for applying the load is a valve body that opens and closes a drain of a washing machine.