JP7338979B2 - Drive unit for washing machine - Google Patents

Description

The disclosed technology relates to a drive unit suitable for washing machines.

Currently, various types of washing machines are being commercialized. Roughly classified, there are vertical washing machines in which a rotary tub for storing laundry rotates around a vertical axis, and drum-type washing machines in which a rotary tub rotates around a horizontal axis or an inclined axis. As a trend, drum-type washing machines are becoming mainstream. All of these washing machines are driven by motors.

In the case of a drum-type washing machine, a series of washing processes such as washing, rinsing, and spin-drying are performed by rotating a drum containing laundry. In washing and rinsing processes in which laundry containing a large amount of water is rotated, low-speed, high-torque rotation force is required. The dehydration process, in which the laundry is rotated so that the laundry is almost dehydrated, requires a high-speed, low-torque rotating force.

Therefore, the motor that drives the washing machine needs to accommodate these rotational forces. Therefore, reduction gears and clutches are generally used. For example, a pulley and a belt may be interposed between the motor and the output shaft, or a plurality of gears such as a planetary gear mechanism may be interposed to reduce the speed. Furthermore, by interposing a clutch, the operating state can be switched.

Conventional examples of such reduction gears and clutches include, for example, Patent Documents 1 to 4. However, in the speed reducer and the clutch disclosed in these publications, the two output shafts are switched, the clutch is arranged outside the motor, or the speed reducer and the clutch are arranged side by side in the axial direction. there is

Unlike such washing machines of a type (indirect drive type) in which a driven object is indirectly driven by a motor, there are also washing machines of a type (direct drive type) in which a driven object is directly driven by a motor. In such a washing machine, inverter control is performed in place of the speed reducer and clutch.

Regarding the disclosed technology, Patent Document 5 discloses a clutch that performs switching by sliding a slider with an electromagnetic force. However, the slider there has a metallic attractor, and by attracting the attractor with an electromagnetic force, it is slid against the elastic force of the spring.

The clutch of Patent Document 5 constantly supplies electric power to generate electromagnetic force in order to hold the slider at a predetermined position.

JP-A-2001-778 Japanese Patent Publication No. 2006-517126 JP 2017-99605 A Japanese Unexamined Patent Application Publication No. 2010-240006 Japanese Unexamined Patent Application Publication No. 2001-017778

Washing machines are required to have a compact size, large washing capacity, low noise, and energy saving.

On the other hand, in the case of a direct-drive washing machine, a single motor with the same magnetic configuration must be controlled to output a rotational force with a large difference in speed and torque. Therefore, it is necessary to drive the motor in greatly different rotational states, and the optimum rotational performance state cannot be maintained. In addition, the motor itself must be large in order to cope with such rotational performance conditions.

On the other hand, in the case of an indirect drive type washing machine, a speed reducer and a clutch are interposed between the driven object and the motor. Therefore, a large space for installing them is required. As a result, the washing capacity is restricted. In addition, the mechanical structure becomes complicated, such as having two output shafts. If the mechanical structure is complicated, loud sounds are likely to be produced.

Both the direct drive method and the indirect drive method have advantages and disadvantages.

Therefore, the main purpose of the technology disclosed is to realize a drive unit suitable for driving a washing machine by efficiently combining each method.

The disclosed technology relates to drive units for washing machines.

The drive unit includes a shaft, a motor that rotates the shaft, and a speed reducer using a clutch and a planetary gear mechanism interposed between the shaft and the motor. The clutch includes a movable portion that slides in the direction of the rotation axis, a pair of fixed portions that are separated from each other in the direction of the rotation axis, and a pair of fixed portions that are slidably connected to each other. and a drive unit for switching the connection state of the speed reducer. The driving section includes a mover provided in the moveable section and including a clutch magnet, and a stator including a clutch coil and a clutch yoke provided so as to face the mover in a radial direction across a gap. have. The clutch magnet has a plurality of magnetic poles arranged in the rotation axis direction.

Specifically, the drive unit can be configured as follows.

The drive unit includes a unit base, a shaft supported by the unit base in a rotatable state about a rotation axis, a motor for rotating the shaft, and a reducer interposed between the shaft and the motor. a machine and a clutch.

The motor has a rotor that is rotatably supported about the rotation shaft, and a stator that is fixed to the unit base and faces the rotor with a predetermined gap therebetween.

The speed reducer is rotatably supported by a carrier fixed to the shaft, a sun gear rotating about the rotation axis, an internal gear arranged around the sun gear, and the carrier. , and a plurality of planetary gears disposed between the sun gear and the internal gear so as to mesh therewith.

The clutch has a movable portion that slides in the direction of the rotation axis, a pair of fixed portions consisting of first and second portions that are spaced apart in the direction of the rotation axis, and a drive portion that slides the movable portion. there is By connecting the movable portion to the first fixed portion, the motor rotates the shaft through the speed reducer in a first mode, and the movable portion is connected to the second fixed portion. is switched to a second mode in which the motor rotates the shaft without using the speed reducer.

The driving section includes a mover provided in the moveable section and including a clutch magnet, and a stator including a clutch coil and a clutch yoke provided so as to face the mover in a radial direction across a gap. have. The clutch magnet has a plurality of magnetic poles arranged in the rotation axis direction.

According to this drive unit, a clutch and a speed reducer are provided between a shaft that outputs driving force and a motor. That is, since these are integrally constructed, the size of the entire unit can be made compact. It is possible to output by switching between a decelerated output and a non-decelerated output from one shaft. Therefore, it is suitable for a washing machine that performs washing and dehydration.

The clutch is a driving portion having a stator, and switches the connection state of the speed reducer by sliding a movable portion having a mover in the rotation axis direction. Since the mover has a clutch magnet having a plurality of magnetic poles aligned in the rotation axis direction, the moveable part can be slid by energizing the clutch coil of the stator. Then, when the power is not supplied, the connecting state of the movable portion can be maintained by the action of the electromagnetic force acting between the clutch yoke and the clutch magnet.

Therefore, electric power consumption can be suppressed because current needs to be supplied to the clutch coil only when switching the clutch.

The drive unit also has a magnetically stable first stable point on one side of a connection position between the movable part and the fixed part when no current is supplied to the clutch coil, and the connection is It may have a magnetically stable second stable point on the other side of the position.

In particular, the clutch magnet has three magnetic poles, and the clutch yoke has a pair of magnetic pole facing portions facing end magnetic poles positioned at both ends of the magnetic poles. preferable.

By doing so, the connected state of the movable portion can be more stably maintained.

In the washing machine, each of the fixed parts has fixed-side projections projecting in the direction of the rotation axis, and the movable part has a pair of movable-side projections that mesh with each of the fixed-side projections when connected to the fixed part. A positioning portion may be provided for positioning the fixed portion and the movable portion at a predetermined position in the circumferential direction where the fixed side protrusion and the movable side protrusion are engaged with each other.

By doing so, the fixed portion and the movable portion are connected by the engagement of the fixed side projection and the movable side projection, so that a stable connection state can be ensured with a simple configuration. Further, since the positioning portion is provided, even if the movable-side projection is displaced in the circumferential direction with respect to the fixed-side projection and does not mesh with each other, they can be meshed smoothly.

The washing machine may further include a cushioning member provided at a connecting portion between the movable portion and the fixed portion to reduce impact during connection.

The movable part is slidably connected to the fixed part. Therefore, when they are connected, an unpleasant impact sound may be generated due to their contact. On the other hand, impact noise can be reduced by providing a cushioning member, such as an elastic member or a vibration damping member, at the connecting portion between the movable portion and the fixed portion to reduce the impact at the time of connection.

The washing machine further includes a control device that controls the motor and the clutch, and the control device includes a motor control section that controls drive of the motor and a clutch control section that controls drive of the clutch. and the clutch control section shares a control circuit with the motor control section.

By doing so, it is possible to suppress an increase in the number of parts such as semiconductor devices, and to realize the device at a low cost.

In the washing machine, the clutch control section supplies a predetermined switching current to the clutch to connect the movable section to the fixed section by applying an impact relaxation current opposite to the switching current to the clutch. may be supplied to

By doing so, the impact noise can be reduced easily and inexpensively without any structural devising.

According to the disclosed technique, a drive unit suitable for driving a washing machine can be realized.

1 is a schematic diagram showing the structure of a washing machine to which the technology disclosed is applied; FIG. FIG. 3 is a schematic side view showing the appearance of a drive unit; 4 is an exploded perspective view showing main members of the drive unit; FIG. FIG. 4 is a schematic cross-sectional view of a main part of the drive unit; FIG. 4 is a schematic perspective view showing portions of the shaft and rotor; It is a schematic perspective view showing a portion of a stator. It is a schematic perspective view which shows the part of a reduction gear. FIG. 4 is a schematic perspective view showing portions of a speed reducer and a clutch; FIG. 4 is a schematic perspective view showing the essential parts of the speed reducer and the clutch. FIG. 4 is a schematic perspective view showing the essential parts of the speed reducer and the clutch. It is a figure explaining switching of a clutch. It is a flowchart which shows the basic operation example of a washing machine. 4 is a flow chart showing an example of clutch switching. It is a schematic perspective view showing the main part of a clutch. FIG. 4 is a diagram for explaining the function of the clutch (state when no power is applied); FIG. 4 is a diagram for explaining the function of the clutch (state when energized); Fig. 3 is a schematic diagram showing a control circuit of the drive unit; FIG. 4 is a schematic diagram showing a control circuit of another drive unit; FIG. 5 is a diagram showing an example of control for reducing impact noise when switching a clutch; FIG. 10 is a diagram showing another example of control for reducing impact noise when switching clutches; It is an enlarged view of a part of a speed reducer.

Embodiments of the disclosed technology will be described in detail below with reference to the drawings. However, the following description is essentially merely an example, and does not limit the present invention, its applications, or its uses. For convenience of explanation, directions such as up and down may be used with reference to the corresponding drawing. In addition, the direction in which the rotation axis extends is called the "rotational axis direction," and the direction around the rotation axis is called the "circumferential direction." is also called "radial direction".

<washing machine>
FIG. 1 illustrates a washing machine 1 to which the technology disclosed is applied. This washing machine 1 is a so-called drum-type washing machine. The washing machine 1 is a so-called fully automatic washing machine, and is configured to automatically perform a series of washing processes including washing, rinsing, dehydration, and the like.

The washing machine 1 mainly includes a housing 2, a tub 3 (stationary tub), a drum 4 (rotating tub), a drive unit 5, a controller 6 (control device), and the like.

The housing 2 is a box-shaped container made up of panels and frames, and constitutes an outer shell of the washing machine 1 . A circular loading slot 2a is formed on the front surface of the housing 2 for loading and unloading laundry. A door 2b having a transparent window is attached to the inlet 2a. The inlet 2a is opened and closed by a door 2b. Above the input port 2a in the housing 2, an operation unit 7 having switches and the like operated by the user is installed.

(Tab 3)
Inside the housing 2, a tab 3 is installed that communicates with the inlet 2a. The tub 3 is a bottomed cylindrical container capable of storing water, and its opening is connected to the inlet 2a. The tab 3 is supported by a damper (not shown) provided inside the housing 2 so as to be stable in a posture in which the center line J thereof is slightly inclined upward toward the front.

Above the tub 3, a water supply device 8 including a water supply pipe 8a, a water supply valve 8b, a drug injection device 8c and the like is provided. An upstream end of the water supply pipe 8a protrudes outside the washing machine 1 and is connected to a water supply source (not shown). A downstream end of the water supply pipe 8 a is connected to a water supply port 3 a opening at the top of the tub 3 . The water supply valve 8b and the medicine injection device 8c are installed in the middle of the water supply pipe 8a in this order from the upstream side.

The chemical injection device 8c accommodates chemicals such as detergents and softeners, and mixes these chemicals with water to be supplied to the tub 3 . A drain port 3b is provided at the bottom of the tub 3. As shown in FIG. The drain port 3b is connected to a drain pump 9. As shown in FIG. The drain pump 9 drains unnecessary water accumulated in the tub 3 to the outside of the washing machine 1 through a drain pipe 9a.

(drum 4)
The drum 4 is a cylindrical container having a diameter slightly smaller than that of the tub 3 and is housed in the tub 3 with the center line J aligned with the tub 3 . A circular opening 4a facing the inlet 2a is formed in the front portion of the drum 4. As shown in FIG. Laundry is put into the drum 4 through the inlet 2a and the circular opening 4a.

A large number of dewatering holes 4b are formed along the entire circumference of the drum 4 (only some of them are shown in FIG. 1). In addition, lifters 4c for stirring are attached to a plurality of locations inside the side portion. A front portion of the drum 4 is rotatably supported by the inlet 2a.

A drive unit 5 is attached to the bottom of the tub 3 . 2 and 3, the drive unit 5 is composed of a shaft 50, a unit base 51, a motor 52, and the like. The shaft 50 passes through the rear portion of the tab 3 and protrudes inside the tab 3 . The tip of the shaft 50 is fixed to the center of the bottom of the drum 4 .

That is, the rear portion of the drum 4 is supported by a shaft 50, and the drive unit 5 directly drives the drum 4 (corresponding to a so-called direct drive system). Thereby, the drum 4 is rotated around the center line J by driving the motor 52 .

The center line J corresponds to the rotation axis (rotation axis J). Since this washing machine 1 is of a drum type, the rotation axis J is arranged so as to extend in a direction inclined with respect to the horizontal direction or in a substantially horizontal direction.

The controller 6 is installed on the top of the housing 2 . The controller 6 is composed of hardware such as a CPU and memory, and software such as control programs and various data. Controller 6 comprehensively controls the operation of washing machine 1 .

An inverter 10 that receives power from an external power supply is installed inside the housing 2 . Inverter 10 is electrically connected to controller 6 and drive unit 5 . The drive unit 5 is driven by the controller 6 controlling the inverter 10 . The drum 4 is thereby rotated.

<Drive unit 5>
As described above, the drive unit 5 is composed of the shaft 50, the unit base 51, the motor 52, and the like. FIG. 4 shows a schematic cross-sectional view of a main part of the drive unit 5. As shown in FIG.

As shown in FIG. 3 , the unit base 51 is made of a substantially disk-shaped metal or resin member attached to the bottom of the tab 3 . A cylindrical shaft insertion hole 511 extending along the center line J is formed in the central portion of the unit base 51 . A pair of ball bearings (a main bearing 512M and a sub-bearing 512S) are attached to both ends of the shaft insertion hole 511 . In FIG. 3, the shaft 50 and the sub-bearing 512S are shown assembled to the motor 52. As shown in FIG. The motor 52 is attached to the back side of the unit base 51 .

The shaft 50 is made of a cylindrical metal member with a diameter smaller than that of the shaft insertion hole 511 . The shaft 50 is inserted into the shaft insertion hole 511 with its tip protruding from the shaft insertion hole 511 . The shaft 50 is supported by the unit base 51 via a pair of ball bearings 512M, 512S. Thereby, the shaft 50 is rotatable around the rotation axis J. As shown in FIG.

The structure of the motor 52 is devised so as to be suitable for driving the washing machine 1 . That is, the washing machine 1 performs washing, rinsing, and spin-drying steps. Therefore, the motor 52 is required to have a high torque output at low speed rotation and a low torque output at high speed rotation.

In general, there is a method in which a speed reducer and a clutch are interposed between the drum and the motor to indirectly rotate the drum (indirect drive method), and a method in which the motor is driven by inverter control to directly rotate the drum. A rotating method (direct drive method) is used.

On the other hand, the drive unit 5 is devised so as to eliminate the shortcomings of each system by efficiently combining the indirect drive system and the direct drive system. That is, the washing machine 1 can realize a compact size with a large washing capacity, low noise, and energy saving.

Specifically, by efficiently incorporating a speed reducer 53 and a clutch 54 interposed between the shaft 50 and the motor 52 into the motor 52 that rotates the single shaft 50 that is the output shaft, these are integrated. is configured to As a result, the motor 52, the speed reducer 53, and the clutch 54 are arranged in a line in a direction substantially perpendicular to the rotation axis J. As shown in FIG. These structures will be described in detail below.

(Base end portion 50a of shaft 50)
As shown in FIG. 4, the base end 50a of the shaft 50 protrudes from the sub-bearing 512S. A screw hole 501 extending along the center line J is formed in the base end portion 50a of the shaft 50 . Serrations extending along the center line J are formed on the outer peripheral surface of the base end portion 50a of the shaft 50 (see FIG. 7). A bolt 503 is fastened to the screw hole 501 via a stopper 502 . By doing so, a main frame 5311 of a carrier 531, which will be described later, is fixed to the base end portion 50a of the shaft 50. As shown in FIG.

(motor 52)
The motor 52 has a rotor 521 and a stator 522 . The motor 52 is a so-called outer rotor type in which the rotor 521 is positioned outside the stator 522 .

As shown in FIG. 5, the rotor 521 is composed of a rotor case 5211, a plurality of magnets 5212, and the like. The rotor case 5211 is composed of a bottomed cylindrical member arranged so that its center coincides with the rotation axis J. As shown in FIG. The rotor case 5211 has a disk-shaped bottom wall 5211a with a round hole at the center, and a cylindrical peripheral wall 5211b continuous around the bottom wall 5211a. Note that the bottom wall 5211a may consist of multiple articles or one article. The rotor case 5211 has a shallow bottom (thickness is small), and the height of the peripheral wall 5211b is smaller than the radius of the bottom wall 5211a.

A cylindrical shaft support portion 5211c facing the peripheral wall 5211b is formed around the round hole opened at the center of the bottom wall 5211a. A gear is formed on the outer peripheral surface of the shaft support portion 5211c, and the shaft support portion 5211c also serves as a sun gear (sun gear 5211c), which will be described later.

A cylindrical sintered oil-impregnated bearing 5213 is fixed inside the shaft support portion 5211c. The shaft support 5211c is slidably supported by the shaft 50 (specifically, the main frame 5311 fixed to the shaft 50) through the sintered oil-impregnated bearing 5213. As shown in FIG. Thereby, the rotor case 5211 is rotatable with respect to the shaft 50 . The sintered oil-impregnated bearing 5213 constitutes a rotor bearing portion.

Each magnet 5212 consists of a rectangular permanent magnet bent in an arc. Each magnet 5212 is fixed to the inner surface of the peripheral wall 5211b of the rotor case 5211 so as to be arranged in series in the circumferential direction. Each magnet 5212 constitutes the magnetic poles of the rotor 521, and is arranged so that S poles and N poles are alternately arranged.

As shown in FIG. 6, the stator 522 is made of an annular member and has an annular core portion 522a and a plurality of tooth portions 522b radially protruding outward from the core portion 522a. The stator 522 is fixed to the unit base 51 via a fixed flange portion 522c provided inside the core portion 522a. Stator 522 is housed in rotor case 5211 .

The core portion 522a and each tooth portion 522b are configured by covering the surface of a magnetic metal stator core 5221 with an insulating insulator. Although not shown, a plurality of coils are formed around each tooth portion 522b by winding conductive wires in a predetermined order. Part of the stator core 5221 is exposed on the end face of each tooth portion 522b located on the outer peripheral portion of the stator 522. As shown in FIG. The exposed portions of these stator cores 5221 are radially opposed to the magnets 5212 of the rotor 521 with a predetermined gap therebetween.

A plurality of coils constitute a three-phase coil group consisting of U, V, and W. A controller 6 controls an inverter 10 to supply an alternating current to each of these coil groups while shifting the phase. By doing so, a magnetic field is formed between each coil group and the magnetic poles of the rotor 521 . The rotor 521 rotates around the rotation axis J due to the action of the magnetic force.

(Reducer 53)
The speed reducer 53 is arranged around the shaft support portion 5211c. The speed reducer 53 is housed in the rotor case 5211 . FIG. 7 shows the speed reducer 53 portion. The speed reducer 53 is a speed reducer using a so-called planetary gear mechanism, and includes a carrier 531, a sun gear 5211c, a plurality of (four in the figure) planetary gears 533, an internal gear 534, and the like.

The carrier 531 has a mainframe 5311 and a subframe 5312 . The subframe 5312 consists of an annular member having four lower bearing recesses 5312a. The subframe 5312 is mounted on the rotor case 5211 via an annular guide plate 535 .

A ring-shaped sliding member 536 is fixed inside the guide plate 535 . The guide plate 535 is rotatably mounted on the bottom wall 5211a of the rotor case 5211 with a sliding member 536 interposed between it and the shaft support 5211c.

The main frame 5311 has a base portion 5311a having a shallow cylindrical shape with a bottom, and a cylindrical shaft stop portion 5311b protruding from the central portion of the base portion 5311a to the rear side thereof. The rear surface of the base portion 5311a is arranged to face the subframe 5312 . A plurality of upper bearing recesses 5311c facing each of the lower bearing recesses 5312a are formed on the back surface of the base portion 5311a.

A serration that fits into the base end portion 50a of the shaft 50 is formed on the inner peripheral surface of the shaft stop portion 5311b. By inserting the base end portion 50a of the shaft 50 into the shaft stop portion 5311b, the main frame 5311 is fixed to the shaft 50 in a non-rotatable state. Around the shaft stop portion 5311b, as described above, the shaft support portion 5211c of the rotor 521 is supported via the sintered oil-impregnated bearing 5213 constituting the rotor bearing portion. The shaft support portion 5211c constitutes a sun gear that rotates about the rotation axis J. As shown in FIG.

The internal gear 534 is made of a substantially cylindrical member having a larger diameter than the sun gear 5211c. A gear portion 534 a is provided below the inner peripheral surface of the internal gear 534 . Gear teeth are formed on the entire circumference of the gear portion 534a. A plurality of inner slide guides 534b, which are linear projections extending in the direction of the rotation axis, are formed on the outer peripheral surface of the internal gear 534 at regular intervals over the entire circumference. These inner slide guides 534b will be separately described later.

The internal gear 534 is arranged around the rotation axis J around the sun gear 5211c. A lower portion of the internal gear 534 is arranged on the guide plate 535 . A ring-shaped sliding member 537 is fixed inside the upper portion of the internal gear 534 (see FIG. 4). The carrier 531 (main frame 5311 ) is rotatably supported by the internal gear 534 via the sliding member 537 .

Each planetary gear 533 is rotatably supported by the carrier 531 and arranged between the sun gear 5211c and the internal gear 534 so as to mesh with them.

Each planetary gear 533 consists of a small-diameter gear member. A pin hole is formed through the center of each planetary gear 533 . Both ends of the pin 5331 inserted into the pin hole are pivotally supported by the upper bearing recess 5311c of the main frame 5311 and the lower bearing recess 5312a of the sub-frame 5312 . Gear teeth are formed on the outer peripheral surface of each planetary gear 533 over the entire circumference. This gear tooth meshes with both the sun gear 5211 c and the internal gear 534 .

Therefore, when the sun gear 5211c rotates at a predetermined speed with the internal gear 534 fixed (unrotatable), each planetary gear 533 rotates around the sun gear 5211c. Thereby, carrier 531 and shaft 50 rotate in a decelerated state.

(clutch 54)
The clutch 54 is arranged around the speed reducer 53 . Clutch 54 is housed in rotor case 5211 . 8, 9 and 10 show portions of the speed reducer 53 and the clutch 54. FIG. The clutch 54 has a slider 541 (movable portion), rotor-side and stator-side lock claws 542R and 542S (fixed portions), and a clutch driver 543 (drive portion). Clutch driver 543 has mover 5431 and stator 5432 .

The slider 541 is made of a cylindrical member having a diameter larger than that of the internal gear 534 . A plurality of outer slide guides 541a, which are linear projections extending in the rotation axis direction, are formed on the inner peripheral surface of the slider 541 at regular intervals along the entire circumference, as shown in FIG. 8 only. These outer slide guides 541 a are configured to mesh with a plurality of inner slide guides 534 b formed on the outer peripheral surface of the internal gear 534 .

The slider 541 is arranged around the internal gear 534 with each of its outer slide guides 541a meshing with each of its inner slide guides 534b. Thereby, the slider 541 is slidable in the rotation axis direction.

A pair of engaging claws 5411R and 5411S, which are rotor-side and stator-side engaging claws, are formed on the outer peripheral surface of the slider 541. As shown in FIG. These engaging claws 5411R and 5411S are composed of a plurality of protrusions (movable side protrusions) protruding in the rotation axis direction, and are formed on the outer peripheral surface of the slider 541 at regular intervals over the entire circumference. The rotor-side engaging claw 5411R is arranged at the lower end of the slider 541, and each protrusion protrudes downward. The stator-side engaging claw 5411S is arranged at the upper end portion of the slider 541, and each protrusion protrudes upward.

A mover accommodating portion 541b for accommodating the mover 5431 is formed between the rotor-side and stator-side engaging claws 5411R and 5411S on the outer peripheral surface of the slider 541. As shown in FIG.

As shown in FIG. 10 , the rotor-side lock claw 542R (first fixed portion) is provided on an annular member 544 attached to the rotor case 5211 . The rotor-side lock claw 542R is composed of a plurality of projections (fixed-side projections) protruding in the rotation axis direction at equal intervals over the entire circumference. These projections protrude upward. Although not shown, these protrusions can be formed simultaneously with other constituent parts or formed integrally with the rotor case 5211 when integrally molding the rotor.

A stator-side lock claw 542 S (second fixed portion) is provided on an annular member 545 attached to the stator 522 . The stator-side lock claw 542S is composed of a plurality of projections (fixed-side projections) protruding in the rotation axis direction at equal intervals over the entire circumference. These protrusions protrude downward. Also, these projections can be configured integrally with the insulator.

The rotor-side lock claw 542R and the stator-side lock claw 542S are arranged so as to face each other at positions separated in the rotation axis direction. The rotor-side locking claw 542R is configured to mesh with the rotor-side engaging claw 5411R, and the stator-side locking claw 542S is configured to mesh with the stator-side engaging claw 5411S.

The space between the rotor-side lock claw 542R and the stator-side lock claw 542S is set larger than the space between the rotor-side engagement claw 5411R and the stator-side engagement claw 5411S. Therefore, when the rotor-side lock claw 542R engages and connects with the rotor-side engagement claw 5411R, the stator-side lock claw 542S does not mesh with the stator-side engagement claw 5411S. When the stator-side locking claw 542S is meshed with the stator-side engaging claw 5411S and connected, the rotor-side locking claw 542R does not mesh with the rotor-side engaging claw 5411R.

As shown in FIG. 9, the mover 5431 of the clutch driver 543 has a slider core 5431a and a clutch magnet 5431b, and is installed in the mover accommodating portion 541b.

The slider core 5431a is made of a metallic cylindrical member having magnetism, and is installed at the back of the mover accommodating portion 541b. The clutch magnet 5431b is composed of a permanent magnet. The clutch magnet 5431b is installed over the entire circumference of the mover accommodating portion 541b in contact with the surface of the slider core 5431a.

As shown in FIG. 10, the stator 5432 of the clutch driver 543 is composed of a clutch coil 5432a, a coil holder 5432b, a holder support 5432c, and the like. The coil holder 5432b is made of an insulating ring-shaped member having a substantially C-shaped cross section with an opening facing radially outward. A clutch coil 5432a is formed by winding an electric wire around the coil holder 5432b.

The holder support 5432c is composed of a pair of upper and lower annular members that sandwich the coil holder 5432b. Holder support 5432 c is fixed to stator 522 . Thereby, the clutch coil 5432a (stator 5432) is configured to face the clutch magnet 5431b (moving element 5431) with a small gap in the radial direction.

The controller 6 controls energization of the clutch coil 5432a. A magnetic field is formed between the clutch coil 5432a and the clutch magnet 5431b by energizing the clutch coil 5432a. Thereby, the slider 541 slides in either one of the rotation axis directions.

Thereby, as shown in FIG. 11, a first mode in which the stator-side engaging claw 5411S engages with the stator-side locking claw 542S and a second mode in which the rotor-side engaging claw 5411R engages with the rotor-side locking claw 542R are performed. and switch to.

In the first mode, internal gear 534 is supported by stator 522 via slider 541 . Rotation of rotor 521 and sun gear 5211 c is thereby transmitted to shaft 50 and carrier 531 via speed reducer 53 . Therefore, the drive unit 5 outputs a rotational force with low rotation and high torque.

On the other hand, in the second mode, the internal gear 534 is supported by the rotor 521 via the slider 541 . Rotation of the rotor 521 and the sun gear 5211 c is thereby transmitted to the shaft 50 and the carrier 531 without going through the speed reducer 53 .

That is, since the rotor 521, the sun gear 5211c, and the internal gear 534 rotate together, the planetary gears 533 do not rotate. As a result, shaft 50 and carrier 531 also rotate together. Therefore, the drive unit 5 outputs a rotational force with high rotation and low torque.

Thus, according to the drive unit 5, the motor 52, the speed reducer 53 and the clutch 54 are arranged in a row in a direction substantially perpendicular to the rotation axis J. 54 are efficiently incorporated, and they are integrally constructed. By switching the clutch 54 , it is possible to output a low-rotation, high-torque rotational force and a low-torque, high-rotational rotational force through the single shaft 50 . Also, in both the first mode and the second mode having different outputs, the rotational speed and torque of the motor 52 can be set to relatively close values, so the motor efficiency can be optimized.

Therefore, this drive unit 5 is compact in size and can output a torque suitable for a washing machine. The drive unit 5 is suitable for washing machines.

<Operation of washing machine 1>
FIG. 12A shows a basic operation example of washing machine 1 .

When the washing machine 1 is operated, first, laundry is put into the drum 4 (step S1). In the case of this washing machine 1, at that time, the detergent or the like is also put into the chemical injection device 8c. Then, an instruction to start washing is input to the controller 6 by operating the operation unit 7 (Yes in step S2). The controller 6 thereby automatically initiates a series of washing processes, such as washing, rinsing, and spin-drying.

Prior to the washing process, the controller 6 measures the weight of the laundry in order to set the amount of water supply (step S3). The controller 6 sets an appropriate amount of water supply based on the measured weight of the laundry (step S4).

After setting the water supply amount, the controller 6 starts the washing process (step S5). When the washing process starts, the controller 6 controls the water supply valve 8b to supply the tub 3 with a set amount of water. At that time, the detergent contained in the chemical injection device 8c is injected into the tub 3 together with the supplied water.

The controller 6 then drives the drive unit 5 to initiate rotation of the drum 4, with the controller 6 prior to the rotation of the drum 4 from a washing or rinsing step, as shown in FIG. 12B. It is determined whether or not (step S10). As a result, if it is a washing or rinsing process, the controller 6 controls the clutch 54 to switch to the first mode (step S11). If it is not a washing or rinsing process, that is, if it is a dewatering process, the controller 6 controls the clutch 54 to switch to the second mode (step S12).

Since this is the washing process, the controller 6 switches the clutch 54 to the first mode. As a result, the drive unit 5 outputs a low-speed, high-torque rotational force. Therefore, the relatively heavy drum 4 can be efficiently rotated at a low speed.

When the washing process ends, the controller 6 starts the rinsing process (step S6). In the rinsing process, the wash water accumulated in the tub 3 is drained by driving the drain pump 9 . Next, the controller 6 performs water supply and agitation in the same manner as in the washing process.

In the rinsing process, the drive unit 5 is driven while the clutch 54 is maintained in the first mode.

After the rinsing process is completed, the controller 6 executes the dehydration process (step S7). In the dewatering process, the drum 4 is rotated at high speed for a predetermined time. Therefore, the controller 6 switches the clutch 54 to the second mode prior to the dewatering process. In the second mode, it is possible to output rotational force with high rotation and low torque. Therefore, the relatively light drum 4 can be efficiently rotated at high speed.

The laundry sticks to the inner surface of the drum 4 by centrifugal force. Water contained in the laundry flows out of the drum 4 . The laundry is thereby dehydrated.

Water accumulated in the tub 3 due to dehydration is discharged by driving the drain pump 9 . When the dehydration process is completed, the completion of washing is notified by sounding a predetermined buzzer, etc., and the operation of the washing machine 1 is terminated.

<Details of Clutch 54>
13 illustrates details of the clutch 54. As shown in FIG. According to this clutch 54, the speed reducer 53 can be stably switched with a simple structure. Since the slider 541 can be held in the connected state by the magnetic action of the permanent magnet when no power is supplied, power consumption can be suppressed.

The clutch magnet 5431b is composed of a plurality of magnetic pole members 54311 formed by arcuate thin permanent magnet plates. Each magnetic pole member 54311 has a plurality of magnetic poles (three in the figure) in which N poles and S poles are alternately arranged in the rotation axis direction. Specifically, when the magnetic pole member 54311 is viewed from the cross-sectional direction, it has an intermediate magnetic pole 54311a positioned at the center and a pair of end magnetic poles 54311b positioned at both ends.

The size of each end magnetic pole 54311b in the rotation axis direction is the same, and the size of the intermediate magnetic pole 54311a in the rotation axis direction is larger than each end magnetic pole 54311b. In the illustrated example, the intermediate magnetic pole 54311a is the N pole, and the end magnetic pole 54311b is the S pole. The magnetic poles 54311a and 54311b extend in the circumferential direction, and the cross-sectional structure of each magnetic pole member 54311 is the same. Also, the magnetic pole member 54311 may have a segment shape or an annular shape.

The holder support 5432c is made of magnetic metal. That is, the holder support 5432c constitutes a clutch yoke (hereinafter the holder support 5432c is referred to as the clutch yoke 5432c). The clutch yoke 5432c has a pair of magnetic pole facing portions 54321, 54321 that are radially opposed to the end magnetic poles 54311b with a small gap therebetween.

A gap portion 54322 is provided between the pair of magnetic pole facing portions 54321 and 54321 so as to face the intermediate magnetic pole 54311a in the radial direction with a small gap therebetween. Therefore, the intermediate magnetic pole 54311a faces the coil holder 5432b through the air gap 54322 thereof.

When the clutch 54 is not energized (when current is not supplied to the clutch coil 5432a), the magnetic action between the mover 5431 and the stator 5432 causes the mover 5431 to move to three different positions. It is designed to have a stable point and one unstable point.

Specific locations of these stable and unstable points are illustrated in FIG. 14A. The curve shown in the table of FIG. 14A shows the position of the mover 5431 relative to the stator 5432 in the rotation axis direction and the driving force (detent torque) generated in the mover 5431 by the magnetic action, that is, the clutch coil excitation. It shows the relationship with the magnetic force that works when it is not (not energized). The former is the vertical axis and the latter is the horizontal axis.

The position “0” of the mover 5431 is the position (neutral position) where the mover 5431 faces the stator 5432 . At the neutral position, each end magnetic pole 54311b faces each magnetic pole facing portion 54321, and the middle magnetic pole 54311a faces the coil holder 5432b. In the neutral position, the thrust is "0". At the neutral position, if the position shifts to the stator side or the rotor side even slightly, a propulsive force is generated in the direction of the shift and increases. Therefore, the mover 5431 becomes magnetically unstable (unstable point P3).

When the mover 5431 is at the neutral position, the slider 541 is positioned apart from the rotor-side lock claw 542R and the stator-side lock claw 542S. Therefore, the engaging claws 5411R and 5411S are not meshed with the locking claws 542R and 542S. Since the mover 5431 is magnetically unstable, the slider 541 slides without stopping. The tip portions of the locking claws 542R and 542S and the engaging claws 5411R and 5411S are formed in a pointed inverted U shape or an inverted V shape (see FIGS. 8 and 10) for easy engagement. ).

When the mover 5431 slides toward the stator (S side), the driving force (positive direction) toward the stator increases, reaches a peak at a predetermined position, and then decreases. Then, the propulsive force becomes "0" again and reaches a magnetically stable point (first stable point P1).

At the first stable point P1, the stator-side end magnetic pole 54311b is located outside the clutch yoke 5432c, the intermediate magnetic pole 54311a faces the stator-side magnetic pole facing portion 54321, and the rotor-side end magnetic pole 54311b It faces the end magnetic pole 54311b and the air gap 54322 on the rotor side. By moving the mover 5431 toward the first stable point P1, the stator-side lock claw 542S is engaged with the stator-side engagement claw 5411S and connected.

In this embodiment, as will be described later, meshing is set at a point P1-1 (connection position Cs) before reaching the first stable point P1 (see FIG. 14B). At the engagement point P1-1, the driving force toward the first stable point P1 is maintained.

When the mover 5431 slides toward the rotor (R side), the driving force (negative direction) toward the rotor increases, reaches a peak at a predetermined position, and then decreases. Then, the propulsive force becomes "0" again and reaches a magnetically stable point (second stable point P2).

At the second stable point P2, the rotor-side end magnetic pole 54311b is located outside the clutch yoke 5432c, the intermediate magnetic pole 54311a faces the rotor-side magnetic pole facing portion 54321, and the stator-side end magnetic pole 54311b It faces the end magnetic pole 54311b and the air gap 54322 on the stator side. As the mover 5431 moves toward the second stable point P2, the rotor-side lock claw 542R is engaged with the rotor-side engagement claw 5411R and connected.

In this embodiment, as will be described later, meshing is set at a point P2-1 (connection position Cr) before reaching the second stable point P2 (see FIG. 14B). At the engagement point P2-1, the driving force toward the second stable point P2 is maintained.

A stator-side connection position Cs where the lock claw 542S and the engagement claw 5411S are meshed and connected, and a rotor-side connection position Cr where the lock claw 542R and the engagement claw 5411R are meshed and connected It is set at the point P1-1 and the engagement point P2-1. As a result, due to the action of the detent torque, it is possible to stably maintain the meshing state at each of the coupling positions Cs and Cr even when no power is supplied.

Note that when the clutch 54 is not energized, the mover 5431 positioned at the neutral position is unstable. That is, when the mover 5431 shifts from the neutral position in the rotation axis direction, the propulsive force acts and the mover 5431 slides easily.

When the clutch 54 is energized, that is, when a current is supplied to the clutch coil 5432a, the slider 541 slides to either the stator side or the rotor side depending on the direction of the current. A first mode of sliding toward the stator and a second mode of sliding toward the rotor are selected depending on the direction of current flow.

FIG. 14B shows the relationship between the position of the mover 5431 relative to the stator 5432 in the rotational axis direction and the propulsive force generated in the mover 5431 when energized. A dashed line represents the detent torque. A solid line L1 represents the driving force in the first mode, and a solid line L2 represents the driving force in the second mode.

In the first mode, current is supplied to the clutch coil 5432a so that the magnetic pole facing portion 54321 on the rotor side becomes the N pole and the magnetic pole facing portion 54321 on the stator side becomes the S pole. As a result, the electromagnetic force generated by the stator 5432 acts on the clutch magnet 5431b, and the driving force T1 directed toward the stator is generated in the mover 5431. FIG. The propulsive force T1 is designed to be large enough to overcome the detent torque and move toward the stator even at the rotor-side connection position. Therefore, the mover 5431 slides toward the stator at any position.

In the second mode, current is supplied to the clutch coil 5432a so that the magnetic pole facing portion 54321 on the rotor side becomes the S pole and the magnetic pole facing portion 54321 on the stator side becomes the N pole. As a result, the electromagnetic force generated by the stator 5432 acts on the clutch magnet 5431b, and the driving force T2 directed toward the rotor is generated in the mover 5431. FIG. The propulsive force T2 is designed to be generated even at the connecting position on the stator side. Therefore, the mover 5431 slides toward the rotor at any position.

(Circumferential Positioning of Clutch 54)
The slider 541 is configured so that it can be positioned in the circumferential direction so that the locking claw 542S smoothly meshes with the engaging claw 5411S.

During the switching of the clutch 54, the mover 5431 is in a free state without meshing. Therefore, as described above, the mover 5431 meshes with the stator 5432 while being guided by the tips of the locking claws 542R and 542S and the engaging claws 5411R and 5411S, which are formed to be easily meshed.

However, it is preferable for the mover 5431 to mesh more smoothly with the stator 5432, such as to reduce impact noise. Therefore, a positioning portion 5433 is provided between the mover 5431 and the stator 5432 . The positioning portion 5433 can position the slider 541 at a predetermined position (reference position) where each locking claw 542S and each engaging claw 5411S are smoothly engaged.

Specifically, as shown in FIG. 13, a gap (inter-pole gap 5433a) of a predetermined size is provided between two adjacent magnetic pole members 54311, 54311. As shown in FIG. Slits 5433b are provided at a plurality of positions in the circumferential direction of the clutch yoke 5432c so as to face each of the magnetic pole gaps 5433a in the radial direction. Each slit 5433b is formed to divide the magnetic pole facing portion 54321 in the circumferential direction.

At the reference position, the inter-magnetic pole gap 5433a and the slit 5433b forming the positioning portion 5433 are set to face each other in the radial direction. When the magnetic pole gap 5433a and the slit 5433b face each other in the radial direction, non-uniform magnetic action is generated between the mover 5431 and the stator 5432 in the circumferential direction. By sensing the non-uniform magnetic action, the slider 541 can be positioned at the reference position.

By controlling the rotation of the motor, the controller 6 positions the slider 541 at the reference position before switching the clutch 54 from the second mode to the first mode. Thereby, the clutch 54 can be switched smoothly.

(Switching control of clutch 54)
Switching control of the clutch 54 is performed by the controller 6 . As schematically shown in FIG. 1, the controller 6 has a motor control section 6a and a clutch control section 6b. The motor control unit 6a controls driving of the motor 52. FIG. The clutch control unit 6b controls driving of the clutch 54. As shown in FIG.

The clutch control section 6b of the drive unit 5 shares the control circuit 60 with the motor control section 6a. An example is shown in FIG. 15A.

15A shows a control circuit 60 (main part) that drives the drive unit 5. FIG. This control circuit 60 has an inverter drive circuit 601 , a motor drive circuit 602 and a clutch drive circuit 603 . Inverter drive circuit 601 , motor drive circuit 602 , and clutch drive circuit 603 are provided in inverter 10 .

The motor 52 has three-phase coil groups 602a, 602a, 602a consisting of U, V, and W, as described above. A motor drive circuit 602 having a neutral point 602b is configured by star-connecting (Y-connecting) the coil groups 602a.

The inverter drive circuit 601 is electrically connected to an external commercial power supply (not shown). The inverter drive circuit 601 incorporates a converter (not shown), which converts alternating current from a commercial power supply into a predetermined direct current voltage and outputs the same. In FIG. 15A, the output DC voltage is schematically represented as a DC power supply 601a.

The inverter drive circuit 601 converts the DC voltage into a predetermined AC voltage by PWM control or the like, and converts the AC voltage into three phases (U-phase, V-phase, W-phase) of different phases. The inverter drive circuit 601 has three arms 601b, 601b, 601b that are installed between a pair of busbars. In each arm 601b, two element units 601c each composed of a switching element and a freewheeling diode connected in anti-parallel are arranged in series.

An output line 601d drawn from between the two element units 601c, 601c of each arm 601b is connected to each coil group 602a. The element unit 601c of each arm 601b is turned on and off at a predetermined timing. As a result, alternating currents having different phases are supplied to the coil groups 602a of each phase, and the motor 52 rotates in synchronization with the alternating currents.

The clutch driving circuit 603 has a clutch coil 5432a, a motor-side wiring 603a, and an inverter-side wiring 603b. One end of the clutch coil 5432a is connected to the neutral point 602b via the motor-side wiring 603a. The other end of the clutch coil 5432a is connected to a potential point (two-divided potential point 603c) that halves the potential of the DC power supply 601a via an inverter-side wiring 603b.

When the motor 52 is driven, alternating currents with different phases are supplied to the coil groups 602a of each phase, as described above. At this time, since the neutral point 602b has substantially the same potential difference as the two-divided potential point 603c, almost no current flows through the clutch coil 5432a.

Therefore, the clutch 54 is not switched when the motor 52 is driven. The connected state of the clutch 54 is maintained by the detent torque.

When switching the clutch 54, the motor 52 is not driven. Therefore, the inverter drive circuit 601 and the motor drive circuit 602 are used to switch the clutch 54 . That is, the clutch control section 6b controls the element unit 601c of each arm 601b. Then, as an example, current is supplied to the motor drive circuit 602 as indicated by the arrow in FIG. 15A. Thereby, a predetermined zero-phase current Iz can be supplied to the clutch coil 5432a.

When a predetermined zero-phase current Iz is supplied to the clutch coil 5432a, a driving force is generated in the slider 541 and the clutch 54 is switched. By changing the control contents of the element unit 601c, the zero-phase current Iz can be caused to flow in the opposite direction. Therefore, the clutch 54 can be switched. According to this control circuit 60, since a semiconductor element or the like can be shared for driving the motor 52 and the clutch 54, an increase in the number of parts can be suppressed and the cost can be reduced.

FIG. 15B shows another configuration example of the control circuit. In this control circuit 60', the configuration of the clutch drive circuit 603 is changed from that of the control circuit 60 described above.

The clutch driving circuit 603 has a clutch coil 5432a, a first wiring 603h, a second wiring 603i, and a relay 603j. One end of the clutch coil 5432a is connected via a first wiring 603h to a connecting portion of one of the three-phase coil groups 602a to the output line 601d of the coil group 602a. The other end of the clutch coil 5432a is connected to a connection portion with the output line 601d of any one other coil group 602a. The relay 603j is arranged on either one of the first wiring 603h and the second wiring 603i.

In the case of this control circuit 60', the clutch 54 can be driven by turning on/off the relay 603j. Also in this case, since the motor 52 and the control circuit 60 are shared, an increase in the number of parts can be suppressed, and the cost can be reduced.

(Reduction of impact noise)
When the clutch 54 is switched, impact noise is generated due to contact between the lock claws 542S and 542R and the engagement claws 5411S and 5411R. Impulsive sound can be an unpleasant noise.

The impact noise generated when switching the clutch 54 can be roughly classified into the following three types. That is, the collision sound (first impact sound) generated when the tips of the locking claws 542S and 542R collide with the tips of the engaging claws 5411S and 5411R in a state where they are not meshed with each other, and the locking claws 542S and 542R Frictional noise (second impact noise) generated in the process of entering the engaging claws 5411S and 5411R, and generated when the locking claws 542S and 542R are completely meshed with the engaging claws 5411S and 5411R. collision sound (third impact sound).

Among these first to third impulsive sounds, the first and third impulsive sounds are particularly likely to become unpleasant noises. Therefore, in order to reduce these impact noises, cushioning members such as elastic members and damping members for reducing impact noise are provided at the connecting portions between the slider 541 and the lock claws 542R and 542S on the rotor side and the stator side. is preferably provided.

Specifically, at least one of a portion provided with the lock claw 542S and a portion provided with the engagement claw 5411S, and a portion provided with the lock claw 542R and the engagement claw 5411R are provided. At least one of the portions in which it is located may be made of a material such as rubber or plastic having elasticity and damping properties. In the latter case, for example, it is conceivable to use an elastic member as the material of the annular member 544 .

At least one of a portion provided with the locking claw 542S and a portion provided with the engaging claw 5411S, and a portion provided with the locking claw 542R and a portion provided with the engaging claw 5411R. At least one of them may be assembled with an elastic member interposed therebetween. In this way, especially the first and third impulsive sounds can be reduced.

The impact noise may be reduced by devising the control of the clutch 54 .

For example, immediately before the clutch control unit 6b supplies a predetermined switching current (current for switching the clutch 54, which corresponds to the zero-phase current Iz described above) to the clutch 54 to connect the slider 541 to the lock claws 542R and 542S. In addition, a current (impact relaxation current) in the opposite direction to the switching current may be supplied to the clutch 54 .

Specifically, as shown in FIG. 14B, switching of the clutch 54 is performed by sliding a slider 541 under the action of driving forces T1 and T2 caused by electromagnetic force. At this time, the detent torque is also acting. Until the neutral position is exceeded, the detent torque acts in the opposite direction to the propulsive forces P1 and P2, but once the neutral position is exceeded, the detent torque also acts in the same direction as the propulsive forces P1 and P2.

Therefore, at least beyond the neutral position, even if the energization of the clutch 54 is stopped, the slider 541 is slid by the detent torque, so the clutch 54 can be switched. Then, at any timing after the slider 541 crosses the neutral position and before the slider 541 is connected to each of the lock claws 542R and 542S (just before means this timing), the shock relaxation current is supplied to the clutch 54. , produces a reverse thrust (indicated by arrow Pr in FIG. 14B).

By doing so, the momentum of the slider 541 is relaxed, so that the impact noise can be reduced. This control is particularly effective in reducing the third impact noise.

Further, the propulsive force is lower before the lock claws 542S and 542R mesh with the engagement claws 5411S and 5411R than after the lock claws 542S and 542R mesh with the engagement claws 5411S and 5411R. Thus, the clutch control section 6b may control the voltage applied to the clutch coil 5432a.

An example of the control is shown in FIG. 16A. The solid line in FIG. 16A shows the relationship between the voltage applied to the clutch coil 5432a and the position of the mover 5431 relative to the stator 5432 in the rotation axis direction. The former is the vertical axis and the latter is the horizontal axis. V0 represents the voltage value normally applied to the clutch coil 5432a.

Section A is a section where the locking claws 542S and 542R are not engaged with the engaging claws 5411S and 5411R, and section B is where the locking claws 542S and 542R are engaged with the engaging claws 5411S and 5411R. It is an interval.

A point P1 indicates a position where engagement between the lock claws 542S and 542R and the engagement claws 5411S and 5411R starts, and a point P2 indicates engagement between the lock claws 542S and 542R and the engagement claws 5411S and 5411R. indicates where the ends.

When the voltage applied to clutch coil 5432a is lowered, the electromagnetic force generated at stator 5432 is also reduced. Therefore, the driving force is weakened. As a result, in section A, the propulsive force is weaker than usual, and the momentum of the slider 541 is suppressed. As a result, the first impact noise generated when the locking claws 542S and 542R mesh with the engaging claws 5411S and 5411R can be reduced.

After the lock claws 542S and 542R mesh with the engagement claws 5411S and 5411R, the voltage is increased to normal voltage. FIG. 16A shows an example in which the voltage is gradually increased to a normal voltage from the start end to the end end of section B. FIG.

As shown in FIG. 16B, the voltage applied to the clutch coil 5432a may be boosted to a normal voltage at the beginning of the section B at once. By boosting the voltage, the propulsive force is restored, so it is possible to switch quickly and stably.

<Details of the speed reducer 53>
FIG. 17 shows an enlarged view of the portion of the speed reducer 53. As shown in FIG. The speed reducer 53 is sealed at its periphery and filled with grease.

Specifically, under the sliding surface of the sliding member 537 (also referred to as the first sliding member 537) that is in rotatable contact with the carrier 531 (main frame 5311), a ring-shaped first A sealing material 538 (an elastic member such as rubber) is attached. Thereby, the space between the carrier 531 and the first sliding member 537 is liquid-sealed.

Under the sliding surface of the sliding member 536 (also referred to as the second sliding member 536) fixed inside the guide plate 535 and rotatably in contact with the rotor case 5211 (shaft support portion 5211c) A ring-shaped second seal member 539 is attached to the side. Thereby, the guide plate 535 and the second sliding member 536 and the rotor case 5211 are liquid-sealed.

Accordingly, the grease can be stably sealed inside the speed reducer 53, and the lubrication of the grease enables the sun gear 5211c, the planetary gears 533, and the internal gear 534 to rotate smoothly.

The material of the first and second sliding members 536 and 537 is preferably self-lubricating resin because it can be made at low cost. In that case, it is preferable to improve the sliding property by applying hard plating to the surface opposite to the sliding surface. Also, the sliding portions where the first and second sliding members 536 and 537 are installed may be configured with ball bearings.

The material of the main frame 5311 is preferably aluminum (aluminum die casting). In that case, it is preferable to anodize the portion of the first sliding member 537 that contacts the sliding surface.

<Modified example of bearing part>
In the above-described embodiment, the drive unit 5 in which the rotor bearing portion that rotatably supports the rotor 521 on the shaft 50 is composed of one sintered oil-impregnated bearing 5213 is exemplified. The rotor bearing portion is not limited to this, and can be appropriately deformed according to specifications.

For example, a pair of ball bearings may constitute the rotor bearing portion. Specifically, instead of the sintered oil-impregnated bearing 5213, a pair of ball bearings are interposed between the shaft stop portion 5311b of the carrier 531 and the shaft support portion 5211c of the rotor case 5211.

Each ball bearing is arranged at a position separated in the rotation axis direction. A pressurizing mechanism is provided together with these ball bearings, and the pressurizing mechanism applies a constant pressurization to these ball bearings.

In that case, one of the pair of ball bearings may be a sintered oil-impregnated bearing. In general, sintered oil-impregnated bearings are not suitable for high-speed rotation, but in the case of this drive unit 5, the rotor bearing portion does not rotate in the second mode of high-speed rotation. Therefore, even if a sintered oil-impregnated bearing is used for the rotor bearing, the reliability of the bearing can be improved.

Note that the technology disclosed is not limited to the above-described embodiments and the like, and includes various other configurations.

For example, in the embodiment, a drum-type washing machine was exemplified, but application to a vertical washing machine is also possible. Further, although the outer rotor type motor in which the rotor magnets are positioned outside the stator has been exemplified, an inner rotor type motor in which the rotor magnets are positioned inside the stator may be used.

The number of magnetic poles of the clutch magnet 5431b is not limited to three, and may be four or more. Accordingly, the number of magnetically stable points may be four or more.

1 washing machine 3 tab (fixed tub)
4 drum (rotating tank)
5 drive unit 6 controller (control device)
10 inverter 50 shaft 51 unit base 52 motor 521 rotor 5211 rotor case 5211c shaft support (sun gear)
5212 magnet 5213 sintered oil-impregnated bearing (rotor bearing)
522 Stator 53 Reduction gear 531 Carrier 533 Planetary gear 534 Internal gear 54 Clutch 541 Slider (moving part)
542R Rotor-side lock claw (fixed part)
542S Stator-side lock claw (fixed part)
543 Clutch driver (drive unit)
5431 mover 54311 magnetic pole member 54311a intermediate magnetic pole 54311b end magnetic pole 5432 stator 5432a clutch coil 5432b coil holder 5432c holder support (clutch yoke)
54321 magnetic pole facing portions 60, 60' control circuit 601 inverter drive circuit 602 motor drive circuit 603 clutch drive circuit

Claims (6)

A drive unit for a washing machine, comprising:
a shaft;
a motor that rotates the shaft;
a speed reducer using a clutch and a planetary gear mechanism interposed between the shaft and the motor;
with
The clutch is
a movable part that slides in the direction of the rotation axis;
a pair of fixing parts positioned apart in the direction of the rotation axis;
a drive unit that switches the connection state of the speed reducer by sliding the movable unit and connecting it to one of the fixed units;
has
The drive unit
a mover provided in the moveable part and including a clutch magnet;
a stator including a clutch coil and a clutch yoke provided so as to face the mover in the radial direction across a gap;
has
The clutch magnet has three magnetic poles arranged in the direction of the rotation axis ,
the clutch yoke has a pair of magnetic pole facing portions that face end magnetic poles positioned at both ends of the magnetic poles,
The movable element has a magnetically stable first stable point on one side of a connection position between the movable portion and the fixed portion when no current is supplied to the clutch coil, and the connection position is drive unit having a magnetically stable second stable point on the other side of the . A drive unit for a washing machine, comprising:
unit base and
a shaft supported by the unit base in a rotatable state about a rotation axis;
a motor that rotates the shaft;
a speed reducer and a clutch interposed between the shaft and the motor;
with
The motor is
a rotor rotatably supported around the rotating shaft;
a stator fixed to the unit base and opposed to the rotor with a predetermined gap therebetween;
has
The speed reducer is
a carrier secured to the shaft;
a sun gear rotating around the rotating shaft;
an internal gear arranged around the sun gear;
a plurality of planetary gears rotatably supported by the carrier and arranged between the sun gear and the internal gear so as to mesh with them;
has
The clutch is
a movable part that slides in the direction of the rotation axis;
a pair of first and second fixing portions spaced apart in the rotation axis direction;
a drive section for sliding the movable section;
has
By connecting the movable portion to the first fixed portion, a first mode in which the motor rotates the shaft via the speed reducer and the movable portion is connected to the second fixed portion. Thereby, the motor is configured to switch to a second mode in which the shaft is rotated without passing through the speed reducer,
The drive unit
a mover provided in the moveable part and including a clutch magnet;
a stator including a clutch coil and a clutch yoke provided so as to face the mover in the radial direction across a gap;
has
The clutch magnet has three magnetic poles arranged in the direction of the rotation axis ,
the clutch yoke has a pair of magnetic pole facing portions that face end magnetic poles positioned at both ends of the magnetic poles,
The movable element has a magnetically stable first stable point on one side of the connecting position between the movable portion and the fixed portion when no current is supplied to the clutch coil, and the connecting position drive unit having a magnetically stable second stable point on the other side of the . A drive unit according to claim 1 or claim 2, wherein
each of the fixed portions has a fixed-side protrusion that protrudes in the direction of the rotation axis;
the movable part has a pair of movable-side projections that mesh with each of the fixed-side projections when connected to the fixed part;
A drive unit, comprising a positioning portion that positions the fixed portion and the movable portion at predetermined positions in the circumferential direction where the fixed side projection and the movable side projection are engaged with each other. A drive unit according to claim 3, wherein
A drive unit, wherein a shock-absorbing member is provided at a connecting portion between the movable portion and the fixed portion to reduce impact during connection. In the drive unit according to any one of claims 1 to 4,
further comprising a control device that controls the motor and the clutch;
The control device is
a motor control unit that controls driving of the motor;
a clutch control unit that controls driving of the clutch;
has
A drive unit, wherein the clutch controller shares a control circuit with the motor controller. A drive unit according to claim 5, wherein
The drive unit, wherein the clutch control section supplies an impact relaxation current opposite to the switching current to the clutch immediately before supplying a predetermined switching current to the clutch to couple the movable portion to the fixed portion. .

Images