JP4721814B2 - Washing machine motor and washing machine equipped with the motor - Google Patents

Description

  The present invention relates to a motor for rotating an inner tub or a pulsator of a washing machine, and more specifically, to a motor for a washing machine in which a stator is formed by stacking iron cores composed of segments divided into a plurality of segments. is there.

The washing machine motor that rotates the inner tub and pulsator of the washing machine is composed of a stator wound with a coil and a rotor that is rotatably arranged on the inner or outer periphery of the stator so that power can be transmitted to the rotor. Connect to the inner tank or pulsator and rotate the inner tank or pulsator.
In general, a motor in which the stator is disposed on the inner peripheral side of the rotor is referred to as an outer rotor type motor, and a motor in which the stator is disposed on the outer peripheral side of the rotor is referred to as an inner rotor type motor.

The stator is configured by stacking a large number of annular iron cores each having a plurality of teeth protruding from the inner peripheral side or the outer peripheral side of the yoke portion.
The iron core is generally produced by punching a metal plate such as a silicon steel plate.
When the iron core is punched out of a metal plate in the form of a ring, there is a problem that the material yield is poor.

In order to improve material yield, as shown in FIG. 5, the iron core (90) is composed of a plurality of segments (91) (91) divided in the circumferential direction, and the divided segments (91) (91) are formed. There has been proposed a stator that is laminated and connected (for example, Patent Document 1).
This iron core (90) is divided so that the number of teeth of each segment (91) (91) is a multiple of the number of phases (three phases), and each segment (91) (91) is shown in FIG. As shown in FIG. 5, the metal plate (60) can be made by arranging the material in the vertical direction and punching it. In addition, the circular hole shown by the code | symbol (93) in a figure is a hole into which the pin for metal mold | die positioning is fitted.

JP 2000-152529 A

When the segments (91) and (91) are divided as described above, assuming that the phases of the currents flowing through the coils wound around the teeth (92) are U, V, and W, as shown in FIG. All seams (94) are located during the same phase, i.e., in the illustrated case, all between U and W.
Since the joint (94) between the segments (91) and (91) generally has a large magnetic loss, if the joints (94) are all located between the same phase, they become magnetically unbalanced and the motor is When it is rotated, there is a risk of causing uneven rotation, vibration, and noise.
Further, when divided by the same number of teeth, the arc length of each segment (91) (91) is the same, so when the segments are arranged on the metal plate (60) as shown in FIG. Since the distance S between the inner circumference side arc P and the outer circumference side arc Q of the segments (91) and (91) adjacent to each other is greatly increased, there is a demand for further improvement of the material yield.

  An object of the present invention is to divide into segments having different numbers of teeth, thereby reducing unbalance in magnetic resistance and further improving the material yield of the stator core, and a motor for the washing machine It is to provide a washing machine equipped with a motor.

In order to solve the above problems, the motor for a washing machine of the present invention is
A stator formed by laminating a plurality of annular cores projecting a plurality of teeth toward the inner periphery or the outer periphery, and winding a coil around the teeth;
A rotor disposed concentrically with the stator and having a plurality of magnets disposed at positions facing the teeth;
In a three-phase AC washing machine motor,
The iron core is divided into four in the circumferential direction, and is formed by connecting segments divided so as to have at least two different types of teeth through a seam ,
The seam between at least one segment and the seam between other segments were divided so that the combination of adjacent phases differed across the seam, and the same piece was placed on the opposite side .

  According to the washing machine motor of the present invention, the arc length and shape of the segment can be changed by dividing the iron core into segments so as to have at least two different numbers of teeth. As a result, as shown in the examples to be described later, when the segments are arranged on the metal plate and the material is taken, the inner and outer arcs of the upper and lower segments can be brought closer to each other, and the material yield can be further improved as compared with the conventional case. Can be improved, and cost reduction can be achieved.

  Also, by changing the number of teeth of the segment to multiple types, the combination of coil phases sandwiching the joints between segments can be changed, so that the unbalance of the magnetic resistance can be reduced, and motor rotation unevenness and vibration can be suppressed. be able to.

  A washing machine (10) equipped with a washing machine motor (30) of the present invention will be described with reference to the drawings. In the following, an embodiment in which the present invention is applied to an outer rotor type motor will be described, but the present invention is naturally applicable to an inner rotor type motor.

FIG. 1 is a sectional view of a washing machine (10) equipped with the washing machine motor (30) of the present invention, and FIG. 2 is an enlarged sectional view of a drive mechanism. The washing machine (10) has a bottomed cylindrical outer tub (12) (water storage tank) that is suspended and supported by the housing (11) and has a number of dewatering holes (not shown) in the peripheral wall. A cylindrical inner tank (13) (dehydration tank) is rotatably supported. A pulsator (15) (stirring blade) for stirring the laundry is rotatably supported on the inner bottom surface of the inner tub (13).
The inner tank (13) has a hollow main shaft (14) extending on the bottom side, and a blade shaft (16) which is a rotation shaft of the pulsator (15) is connected to the main shaft (14) via an oilless metal (17). It is loosely fitted. The main shaft (14) and the blade shaft (16) pass through the outer tub (12) and are attached to the lower surface of a tray (18) provided on the lower side of the outer tub (12) (20 ) To the washing machine motor (30).
The power transmission mechanism (20) includes a speed reduction mechanism (22) and a clutch mechanism (23) (for example, a clutch spring mechanism) formed of a speed reduction planetary mechanism inside an outer cover (21) fixed to the lower surface of the tray (18). The drive shaft (31) is connected. The speed reduction mechanism (22) and the clutch mechanism (23) transmit the driving force of the washing machine motor (30) to the blade shaft (16) and rotate only the pulsator (15) during the easy-to-wash operation. . In addition, during the dehydration operation, the driving force of the washing machine motor (30) is transmitted to both the blade shaft (16) and the main shaft (14), and the inner tub (13) and the pulsator (15) are rotated together. So that the power transmission is switched. The power transmission mechanism between the main shaft (14) and the blade shaft (16) and the drive shaft (31) of the washing machine motor (30) is not limited to the above, and when deceleration is not required Alternatively, a so-called direct drive mechanism in which the power transmission mechanism (20) is omitted may be used.

  As shown in FIG. 2, the washing machine motor (30) can be exemplified by an outer rotor type motor in which a stator (40) is arranged on the inner side and a rotor (70) is arranged on the outer side. The stator (40) is accommodated in the stator housing (54) attached to the outer peripheral cover (21) of the power transmission mechanism (20), and the rotor (70) covers the outer periphery of the stator (40). Thus, it fits concentrically with the stator (40).

  The stator (40) is formed by stacking a plurality of annular iron cores (41) shown in FIG. The iron core (41) includes an annular yoke portion (42) and teeth (43) (43) protruding from the outer periphery of the yoke portion (42). The illustrated iron core (41) has 18 teeth, and the teeth (43) are projected at regular intervals, that is, at 20 ° intervals. The teeth (43) are portions where the coil (51) is wound when the iron core (41) is laminated, and the tip is enlarged.

As shown in FIG. 3, the iron core (41) is composed of segments (45) and (46) divided into a plurality of pieces in the circumferential direction so that the number of teeth differs by at least two kinds. For example, when the number of teeth of the iron core (41) is 18, the iron core (41) is composed by combining two segments (45) with five teeth and two segments (46) with four teeth. can do.
FIG. 4 shows a desirable example of material removal when the segments (45) and (46) are punched from the metal plate (60).
As shown in FIG. 4, the segment (45) having 5 teeth and the segment (46) having 4 teeth use a metal plate (60) in the longitudinal direction (in the example shown, a rectangular metal plate). However, in practice, the metal plate (60) is a long coil and is continuous in the vertical direction in the figure), and the material can be taken alternately. Since the number of teeth of the segments (45) and (46) is different, the arc length and shape of the segments (45) and (46) are also different, and the segments (45) (46 ) Can be shortened (see FIGS. 4 and 6), and the material yield can be further improved.
Specifically, when the material of the iron core (41) is removed in the manner of the present invention as shown in FIG. About 80% of the required area of the metal plate is sufficient. Therefore, the material yield can be improved by about 20%. In FIG. 6, the size of the metal plate when the material of the iron core is removed in the manner of the present invention is indicated by a one-dot chain line R.

In the metal plate (60), the material of the segments (45) and (46) is removed as described above, and the holes (61) and (61) in which the mold positioning pins are fitted are removed. After taking these materials, the metal plate (60) is punched once or a plurality of times to produce segments (45) and (46) having a predetermined shape.
The segments (45) and (46) mesh with each other when they are stacked on the teeth (43) so that the segments (45) and the segments (46) are stacked and crimped so as not to be displaced. It is desirable to provide a caulking recess (not shown). This can be formed simultaneously with punching. The caulking dent may be formed on all the teeth (43) or only on some of the teeth (43).
Further, the end of the yoke part (42) of the segment (45) (46) is connected to the engaging recess (47) at one end and the other end to connect the segment (45) (46), respectively. A nail (48) is formed.

As described above, the segments (45) and (46) punched from the metal plate (60) are laminated and crimped for each segment (45) and for each segment (46). At the time of caulking, the caulking dents provided on the teeth (43) mesh with each other, so that the joining strength between the segments can be increased and separation can be prevented.
In the case of this example, in order to constitute the iron core (41), two laminated bodies of segments (45) and two laminated bodies of segments (46) are produced.
As shown in FIG. 3, the produced laminate is arranged so that the segments (45) and the segments (46) are arranged alternately, and the engaging recesses (47) and the engaging claws (48) are fitted together to form an annular connection. Then, the iron core (41) is produced.

As shown in FIG. 2, the produced iron core (41) is molded with PBT resin (polybutylene terephthalate resin) except for the tip of the teeth (43). The resin mold (52) is implemented to ensure insulation between the coil (51) and the iron core (41). The reason why the tip of the teeth (43) is not resin-molded is to shorten the distance between the rotor (70) described later and the tips of the teeth (43) as much as possible.
In addition, it is desirable to form ribs (53) and (53) for preventing the coil (51) from shifting during resin molding.

  After the iron core (41) is resin-molded, the coils (51) are wound around the teeth (43), respectively, and predetermined electrical wiring is applied to produce the stator (40). In the case of a three-phase AC motor, three sets of coils (51) are wound around each tooth (43) in turn.

In order to attach the waterproof and stator (40) to the outer peripheral cover (21) of the power transmission mechanism (20), the stator (40) thus prepared is resin-molded, and the stator housing (54) It is desirable to cover. Examples of the resin to be molded include BMC resin (bulk molding compound resin, for example, thermosetting unsaturated polyester). In this case as well, the tip of the teeth (43) is exposed without being resin-molded.
As mentioned above, the stator (40) is molded with waterproof resin, so that even if water enters the motor (30), the coil (51) will not be short-circuited, and deterioration such as rust will be prevented. There are advantages that can be made.

After the stator (40) is enclosed by the stator housing (54), the stator housing (54) is attached to the outer cover (21) of the power transmission mechanism (20), and the rotor (70) is attached to the outer periphery of the stator (40). Is placed.
The rotor (70) includes an annular yoke (74) having a substantially L-shaped cross section, and a plurality of permanent magnets (72) (72) disposed on the inner peripheral wall surface of the yoke (74). (72) is covered with a resin (73) such that the surface is exposed from the cylinder inner wall (71) of the rotor (70). The magnets (72) are arranged so that the polarities are alternate.
A drive shaft (31) of the power transmission mechanism (20) is connected to the center of the bottom surface of the rotor (70).

In the washing machine motor (30) configured as described above, when the coil (51) is energized, a three-phase alternating current flowing in the coil (51) generates a rotating magnetic field in the stator (40), and the rotor (70) Rotate.
The rotation of the rotor (70) is transmitted to the power transmission mechanism (20), the main shaft (14) and the blade shaft (16) rotate, and the inner tank (13) and the pulsator (15) rotate.

In the present invention, it is desirable to divide the segments (45) and (46) as follows.
The number of segments (45) and (46) into which the iron core (41) is divided is 2 or more, and is preferably 4. This is for the purpose of taking out the material and preventing the assembly process from becoming complicated.
In this case, it is desirable that the segments (45) and (46) are arranged so that the same piece comes to each other. As a result, as shown in FIG. 3, the seam (49) is positioned approximately every 90 ° in the radial direction with respect to the center of the iron core (41), ensuring mechanical stability and reducing strength. This is because it can be prevented.

Moreover, although the number of teeth of the divided | segmented segment can be made into multiple types, it is two types desirably. In this case, one segment (45) has a larger number of teeth than the other segment (46), but the difference is preferably 1. This is because the seam (49) between at least one segment and the seam (49) between other segments can be divided so that the combination of adjacent phases (U, V, W) across the seam (49) is different. Because. In the example shown in FIG. 3, it can be seen that there are two seams (49) between W and U and two between V and W, respectively.
Thus, by positioning the seam (49) in the yoke part (42) with different amount of magnetic flux passing through, the magnetic loss generated in the seam (49) can be made uniform, and as a result, the magnetic resistance is unbalanced. This is because the vibration becomes smaller and vibration during rotation can be suppressed.

  As described above, the washing machine motor (30) of the present invention has a small unbalance of magnetic resistance generated in the stator (40) and a small vibration during rotation. Low vibration and low noise can be achieved.

  INDUSTRIAL APPLICABILITY The present invention is suitable as a washing machine motor that has less vibration and can further improve the material yield.

It is sectional drawing of a washing machine. It is an expanded sectional view of the drive mechanism of a washing machine. It is a top view of the iron core formed by connecting the segments divided in the manner of the present invention. It is a top view which shows the state which took the material for the segment divided | segmented in the point of this invention to the metal plate. It is a top view of the iron core formed by connecting the segments divided in the conventional manner. It is a top view which shows the state which returned the segment divided | segmented in the conventional way to the metal plate.

Explanation of symbols

(10) Washing machine
(20) Power transmission mechanism
(30) Motor for washing machine
(40) Stator
(41) Iron core
(42) Relay part
(43) Teeth
(45) Segment
(46) Segment
(49) Seam
(60) Metal plate
(70) Rotor

Claims (3)

A stator formed by laminating a plurality of annular iron cores with a plurality of teeth projecting toward the inner periphery or the outer periphery, and winding a coil around the teeth;
A rotor disposed concentrically with the stator and having a plurality of magnets disposed at positions facing the teeth;
In a three-phase AC washing machine motor,
The iron core is divided into four in the circumferential direction, and is formed by connecting segments divided so as to have at least two different types of teeth through a seam ,
At least one seam segments each other, the seam of each other other segments, by dividing the segment combination is different phases adjacent to each other with a seam, that you have arranged so that the same piece respectively facing A motor for a washing machine. The motor for a washing machine according to claim 1 , wherein the number of teeth of the divided segments is two, and one segment has one more tooth than the other segment. A washing machine comprising the washing machine motor according to claim 1 or 2 .

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