JPH11341714A - Stator of motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent as much as possible crackings and separations in a covering member, which is formed by molding for covering the outer surfaces of the yoke and the teeth of a stator core. SOLUTION: Grooves 6 which extend in the axial direction are formed in the inner circumference of the yoke of a stator core 1. The groove 6 is formed at a position between the respective adjacent teeth 5 and 5, and furthermore at an approximately central position between gates 10 and 10 for the molding of a covering member 7. The covering member 7 which is made of insulating resin is formed by molding so as to cover the outer surfaces of the stator core 1, and resin filling parts 9 filling the respective grooves 6 are formed integrally with the covering member 7. Since the covering member 7 is firmly fixed to the stator core 1 by the resin filling parts 9, crackings and separations in the covering member 7 can be restrained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor stator in which a covering member made of an insulating resin is provided on the outer surfaces of a yoke portion and each tooth portion of a stator core by molding.

[0002]

Conventionally, a stator of a motor has a stator core formed by laminating a plurality of steel plates punched into a predetermined shape, and an insulating end plate made of an insulating resin separately molded is formed on the stator core. A coil is wound around each tooth portion which is mounted and covered with the insulating end plate.

[0003] However, the work of assembling the insulating end plate to the stator core is troublesome. In particular, in the case of a stator core having a large number of teeth, the assembling operation is troublesome because the shape of the insulating end plate is complicated.

On the other hand, it has been considered to adopt a configuration in which a covering member made of an insulating resin is provided by molding on the outer surfaces of the yoke portion and each tooth portion of the stator core.
In this case, there is no need to attach an insulating end plate to the stator core.

However, in the case of such a configuration, cracks or peeling may occur in the covering member due to the temperature change during the curing of the resin after the molding of the covering member or the operation as a motor. There was a problem that it was easy to do.

The present invention has been made in view of the above circumstances, and has as its object to cover the outer surfaces of a yoke portion and each tooth portion of a stator core with a coating member provided by molding. An object of the present invention is to provide a motor stator that can minimize the occurrence of cracks and peeling of members.

[0007]

In order to achieve the above object, a stator of a motor according to the present invention comprises a stator core having a plurality of teeth on an outer peripheral portion or an inner peripheral portion of a yoke portion; A coating member made of insulating resin provided by molding so as to cover the outer surfaces of the yoke portion and each tooth portion, and a side of the yoke portion opposite to the teeth portion, and at the time of molding the coating member. A plurality of grooves extending in the axial direction of the stator yoke are provided so as to be located substantially at the center between adjacent gates, and are integrally provided on the covering member so as to be filled in the respective grooves. It is characterized by having a configuration including a resin filling portion.

[0008] In the above-described configuration, since the covering member for covering the outer surface of the yoke portion and each tooth portion of the stator core is provided by molding, the separately formed insulating end plate is assembled to the stator core. You don't have to.

By the way, the following can be considered as causes of cracks or peeling of the covering member covering the stator core. First, when molding the covering member,
A weld line is formed in a portion where the molten resins (hot water) collide with each other, and a crack is easily generated in the weld line portion when the resin is cured. In addition, due to the difference in thermal expansion coefficient (thermal shrinkage rate) between the materials of the stator core (metal) and the covering member (resin), cracks and peeling are likely to occur in the covering member with a change in ambient temperature.

Therefore, in the present invention, each groove formed in the yoke portion of the stator core is substantially at the center between the adjacent gates, and this portion is where a weld line is easily formed at the time of molding the covering member. . Since the groove is filled with a resin filling part integral with the covering member,
The covering member is in a state of being firmly fixed to the stator core at the resin filled portion. For this reason, even when the resin is cured during molding of the covering member, and even when there is a change in the surrounding temperature, the occurrence of cracks and peeling of the covering member is suppressed.

In the present invention, it is preferable that the groove formed in the yoke of the stator core has a shape in which the inside is wider than the opening, or a shape having an escape resistance portion. In such a case, the resin-filled portion filled in the groove becomes more difficult to fall out of the groove, so that the coating member can be further prevented from peeling from the stator core.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. In this embodiment, a case where the present invention is applied to a stator used for an outer rotor type motor will be described. First,
FIG. 1 is a cross-sectional plan view of a main part in a state after a covering member is formed on a stator core, FIG. 2 is a plan view of the entire stator core, and FIG. 3 is a vertical sectional side view thereof.

In FIGS. 1 to 3, the stator core 1 is formed by stacking a large number of steel plates 2 made of a silicon steel plate punched in a predetermined shape,
(See FIG. 1).
The stator core 1 has a configuration in which an annular yoke portion 4 and a large number of teeth portions 5 are provided on an outer peripheral portion of the yoke portion 4 so as to project radially. The caulking portion 3 is disposed at a tip end portion of each tooth portion 5 and a portion of the yoke portion 4 corresponding to each of the plurality of tooth portions 5.

In the yoke portion 4 of the stator core 1, the stator core is located at an inner peripheral portion opposite to the teeth portion 5 and at a substantially central portion between the adjacent teeth portions 5, 5. 1 axial direction (vertical direction in FIG. 3)
Is formed. This groove 6 is formed as shown in FIG.
As shown in the figure, the yoke portion 4 has a substantially circular shape with one opening on the inner peripheral side, and has an inner shape wider than the opening 6a, and an inner peripheral portion 6b deeper than the opening 6a. Constitutes the escape resistance portion.

A covering member 7 made of an insulating resin is provided on the outer surfaces of the yoke portion 4 and the teeth portions 5 of the stator core 1 by molding so as to cover substantially the entire surface thereof. As a material of the covering member 7,
In this case, polyphenylene sulfide (PPS), which is a material having excellent heat resistance, is used as a main component and glass powder is mixed with the material, and this material will be described later.

The covering member 7 has a large number of supporting exposed portions 8 formed by portions corresponding to supporting portions for supporting the stator core 1 in a molding die (not shown) when molding the covering member 7. I have. In this case, the supporting exposed portions 8 are arranged at a portion corresponding to the tip of each tooth portion 5 and at a plurality of locations on the inner peripheral portion of the yoke portion 4. Each of the groove portions 6 in the inner peripheral portion of the yoke portion 4 is filled with a resin filling portion 9 integral with the covering member 7.

Here, a gate 10 (indicated by a two-dot chain line in FIG. 1) for injecting a resin is formed in a molding die when the covering member 7 is molded. As shown by a two-dot chain line in FIG. 1, they are arranged so as to be located on the yoke portion 4 and on an extension of each tooth portion 5.
Are arranged so as to be located substantially at the center between the adjacent gates 10 and 10.

The covering member 7 has coils (not shown) wound around the teeth 5 at both axial ends (upper and lower ends in FIG. 3) of portions corresponding to the tips of the teeth 5. (See FIGS. 2 and 3)
Is provided, and at a portion corresponding to both ends in the axial direction of the yoke portion 4, a crossover wire arranging portion 12 for arranging the crossover wire of the coil is provided. Further, in FIG. A plurality of terminal processing units 13 for processing the terminals of the coil are provided in a portion corresponding to the unit.

Further, the covering member 7 is integrally provided with a plurality of mounting boss portions 14 located on the inner peripheral side of the yoke portion 4. A plurality of mounting bosses 14 are provided with a metal tubular portion 15 by insert molding. On the base end side of the mounting boss 14, a recess 16 for stealing the meat is formed.

When the covering member 7 is formed on the stator core 1 having the above-described structure, the following operation is performed. That is, first, the stator core 1 is housed and arranged in the molding die, and the cylindrical portion 15 of the mounting boss portion 14 is arranged. At this time, the stator core 1 is supported by a support (not shown) in the molding die. After this, each gate 1 of the molding die
The resin melted from 0 is injected into the mold, and the resin is cured, so that the covering member 7 is formed on the outer surface of the stator core 1 so as to cover the same. At this time, each groove 6 of the yoke portion 4 is filled with the resin filling portion 9 integrated with the covering member 7, and the mounting boss portion 14 and the like are integrally formed. After the resin is cured, the molding is completed by removing the mold.

In the stator core 1 configured as described above, a coil (not shown) is wound around the outer periphery of each of the teeth portions 5 to form an outer rotor type motor stator.

According to the first embodiment, the following effects can be obtained. Since the covering member 7 is provided on the outer surfaces of the yoke portion 4 and the teeth portions 5 of the stator core 1 by molding, it is not necessary to perform an operation of assembling a separately molded insulating end plate to the stator core. , Workability can be improved.

Each groove 6 formed in the yoke 4 of the stator core 1 is located substantially at the center between the adjacent gates 10, 10, and the weld line L is formed when the covering member 7 is formed.
(Refer to the two-dot chain line in FIG. 1). Since the groove 6 is filled with the resin filling portion 9 integrated with the covering member 7, the stator core is formed as the covering member 7 at the resin filling portion 9. 1 is firmly fixed. For this reason, even when the resin is cured during molding of the covering member 7, even if a contraction force that pulls the weld line portion from both sides in the circumferential direction is applied with the contraction of the covering member 7, a crack is formed in the weld line portion. This can be prevented as much as possible. In addition, for example, in a state where the covering member 7 is used as a motor, the surrounding member 7 changes with a change in ambient temperature.
Even if is expanded or contracted, it is possible to minimize the occurrence of cracks and peeling in the covering member 7 due to the expansion and contraction forces.

In this case, in particular, since the inside of the groove 6 has a shape wider than the opening 6a and the inner peripheral portion 6b forms a resistance portion, the resin filled portion 9 comes out of the groove 6. Is more reliably prevented, and the occurrence of cracks and peeling in the covering member 7 can be further prevented.

Each of the gates 10 when forming the covering member 7 is disposed on an extension of each of the teeth 5, and each of the grooves 6 is disposed at a substantially central portion between the teeth 5. So, from those gates 10 each tooth part 5
The resin flows well around the gate and the gate 1
0 and the arrangement of the groove portions 6 are well balanced, so that good molding can be performed. Further, in the yoke part 4, since the position of the groove part 6 and the position of the caulking part 3 are shifted, it is possible to prevent the magnetic properties from being reduced as much as possible.

On the other hand, since the mounting boss 14 is provided integrally with the covering member 7, the number of parts can be reduced and the number of assembling steps can be reduced as compared with the case where a separate member is used for the mounting boss. Thus, the stator can be easily attached to a predetermined portion for attaching the motor. Further, since the metal cylindrical portion 15 is provided on the mounting boss portion 14 by insert molding, the strength of the mounting boss portion 14 can be increased.

Here, the stator used in this embodiment has a large output as a motor (torque of 300 [k
g · cm], large (diameter is about 26 cm), coil temperature is high (about 120 ° C.), and applied voltage is large (2
00V or more), the material used for the covering member 7 is
It is necessary to use a material having good fluidity, excellent heat resistance, sufficient strength, and hardly causing cracks due to heat shock.

The material used for the covering member 7 will be described with reference to FIG. In FIG. 5, samples A and
B, C, and D are the materials determined to be preferable in this example, and Comparative Samples 1 and 2 are the materials determined to be unfavorable. These samples A to D and comparative samples 1 and 2
Has a structure in which polyphenylene sulfide is a main component and glass powder is mixed with the main component as described above. FIG. 5 shows the mixing ratio of glass, the physical properties of the flexural modulus, the melt viscosity, and the flow length of each of the samples A to D and the comparative samples 1 and 2, and the determination when the coating member 7 was used. The results are shown. The comparative sample 1 uses a product number: 1140A6 manufactured by Polypla, and the comparative sample 2 uses a product number: 1130A6 manufactured by Polypla.

The methods for measuring the flexural modulus, melt viscosity and flow length are described in ASTM (The American Society).
for Testing and Materials). In this case, the measurement conditions of the melt viscosity are as follows: the temperature of the melted material is 310 ° C., and the speed of the pressing member is 1216 [m
m / s]. The measurement conditions of the flow length are as follows: the temperature of the molten material is 315.5 ° C., and the weight of the weight is 216.
0 g, nozzle diameter 2.0995 mm, nozzle length 8 mm, dwell time 5 minutes.

The result of determination when used as the covering member 7 was determined based on moldability, strength after molding, the degree of occurrence of cracks and peeling, and the like. As can be seen from this determination result, the samples A, B, C, and D are preferable as the covering members 7, and the comparative samples 1 and 2 have the covering members 7.
Was determined to be undesirable.

Therefore, as the material of the covering member 7, the mixing ratio of glass is preferably 20 to 30%, the flexural modulus is 5,000 to 10,000 [MPa], and the melt viscosity is 150 to 200 [Pa · s]. ], The flow length is 15 to 50 [m
m / 10 min] is preferable.

FIGS. 6, 7 and 8 show modifications 1, 2 and 3 of the groove formed in the yoke 4, respectively. Of these, the groove 20 in FIG. 6 has an inner side that is larger in the circumferential direction than the opening 20a in an elliptical shape, and an inner peripheral part 20b deeper than the opening 20a forms a resistance part. .

The groove 21 in FIG. 7 is L-shaped and has substantially the same thickness from the opening 21a to the tip, but the inner peripheral portion 21b on the tip end side of the bent portion comes off and forms a resistance portion. I have. The groove 22 in FIG.
In this case as well, the thickness is substantially the same from the opening 22a to the tip, but the inner peripheral portion 22b of the bent portion comes off and forms a resistance portion.

FIGS. 9 and 10 show a second embodiment of the present invention. The second embodiment differs from the first embodiment in the following points. That is, the stator core 1
In the steel plate 24 located at both ends in the axial direction (steel plates located at the upper and lower ends in FIG. 9), notches for forming the groove 6 are not formed, and the axial direction of the groove 6 The end is closed at the closing portion 24a.

In such a configuration, the resin filling portion 9 filled in the groove 6 is prevented from coming off in the axial direction by the closing portion 24a.
As a result, peeling in the axial direction from the stator core 1 can be prevented.

FIG. 11 shows a third embodiment of the present invention. The third embodiment differs from the first embodiment in the following points. That is, the stator core 1 is configured by connecting the plurality of divided cores 25 divided in the circumferential direction at the connection portion 26. Each connecting portion 26 is located between the adjacent teeth 5 and 5, and one of the connecting portions 26 is formed by a trapezoidal fitting groove 27 whose back side is wider than the opening, and the other is a tip portion. Is formed by a trapezoidal fitting protrusion 28 wider than the base end portion, and the fitting protrusion 28 is fitted into the fitting groove 27 in the axial direction.

In this case, the connected divided cores 2
Between the inner and outer peripheral sides of the yoke part 4, grooves 29, 29 are formed between the inner and outer peripheral parts of the yoke part 4, and these grooves are filled with a resin filling part 30 integrated with the covering member 7. ing. Therefore, the groove 29 in the connection portion 26
Has a configuration also serving as the groove 6. Further, in this case, the resin filling portion 3 integrated with the covering member 7 is also provided in the gap formed between the bottom of the fitting groove 27 and the tip of the fitting projection 28.
1 is filled.

FIG. 12 shows a fourth embodiment of the present invention. The fourth embodiment differs from the first embodiment in the following points. That is, the covering member 3 made of insulating resin
5 is divided into a coil bobbin portion 36 provided to cover the teeth portion 5 of the stator core 1 and a coating portion 37 provided to cover other portions. In this case, the coil bobbin portion 36 is primarily formed, and thereafter, the coating portion 37 is provided by secondary forming. The coil bobbin portion 36 is made of a material having excellent heat resistance, for example, PPS.
For the covering portion 37, a material having excellent tracking resistance (property of hardly forming carbide), for example, PBT (polybutylene terephthalate) or PS (polyamide) is used.

In the fourth embodiment, the covering member 35 is divided into the coil bobbin portion 36 and the other covering portion 37, so that a material suitable for the purpose can be used.

FIG. 13 shows a fifth embodiment of the present invention. The fifth embodiment differs from the first embodiment in the following points. That is, instead of integrally providing the mounting boss portion on the covering member 7, a separately manufactured mounting member 38 is mounted. In this case, an engaging portion 39 is provided integrally with the covering member 7, and an engaging claw 40 provided integrally with the mounting member 38 is engaged with the engaging portion 39, so that the attaching member 38 is attached to the covering member 7. As a result, the stator core 1
It is configured to be attached to. The attachment member 38 is attached to a predetermined portion via a buffer member 41 made of rubber.

In the case of such a configuration, the shape of the covering member 7 can be simplified, and the mounting member 38 is mounted via the buffer member 41, so that the vibration of the stator causes the stator to be mounted. Transmission to the other party can be prevented as much as possible. Note that the cushioning member 41
May be insert-molded when the mounting member 38 is formed.

FIG. 14 shows a sixth embodiment of the present invention. The sixth embodiment differs from the first embodiment in the following points. That is, a metal reinforcing plate 43 is disposed at both axial ends of the stator core 1, and the reinforcing plate 43 is entirely covered with the covering member 7. In this case, the reinforcing plate 43 may be disposed only at one end in the axial direction.

FIG. 15 shows a seventh embodiment of the present invention. The seventh embodiment differs from the first embodiment in the following points. That is, the stator core 45 is used for a stator of an inner rotor type motor, and has a ring-shaped yoke portion 46 and a plurality of teeth portions provided to protrude toward the inner peripheral side of the yoke portion 46. 47. Further, the stator core 45 is configured by connecting a plurality of divided cores 48 divided in the circumferential direction at the connection portion 26, as in the third embodiment. An outer peripheral portion of the yoke portion 46 of the stator core 45 opposite to the teeth portion 47, and
A groove 6 extending in the axial direction of the stator core 45 is formed substantially at the center between the adjacent teeth 47, 47.

As in the first embodiment, a covering member 7 made of an insulating resin is provided on the outer surfaces of the yoke 46 and the teeth 47 of the stator core 45 by molding so as to cover almost the entire surface thereof. Have been. By this molding, each groove 6 of the stator core 45 and the connecting portion 26
The resin filling portions 9, 30, 31 integral with the covering member 7 are filled in the groove portions 29 and the gaps. Also in this case, the gate 10 of the molding die for molding the covering member 7 is disposed so as to be located on the yoke portion 36 and on an extension of each tooth portion 47 as shown by a two-dot chain line.

In the seventh embodiment having such a configuration, basically, the same operation and effect as those of the first embodiment can be obtained.

[0046]

As is clear from the above description, according to the present invention, the following effects can be obtained. Claim 1
According to the stators of the motors of (1) and (2), since the covering member for covering the yoke portion and each tooth portion of the stator core is provided on the outer surface by molding, the separately formed insulating end plate is assembled to the stator core. There is no need to perform work, and workability can be improved. By forming a groove in the yoke and filling the groove with a resin-filled portion integral with the covering member, the covering member is firmly fixed to the stator core at the resin-filled portion. Therefore, it is possible to minimize the occurrence of cracks and peeling in the covering member.

According to the motor stator of the third aspect, the number of parts can be reduced and the number of assembling steps can be reduced as compared with the case where a separate member is used for the mounting boss. According to the stator of the motor of the fourth aspect, the strength of the mounting boss can be increased. According to the motor stator of the fifth and sixth aspects, the resin-filled portion is more reliably prevented from falling out of the groove, and the occurrence of cracks and peeling of the covering member can be further prevented.

According to the motor stator of the present invention, the resin can be satisfactorily rotated around the teeth from the gate, and the arrangement of the gate and the groove is well-balanced, so that good molding can be performed. it can. According to the motor stator of the eighth aspect, since the positions of the groove and the caulked portion are shifted in the yoke, it is possible to prevent the magnetic characteristics from being reduced as much as possible.

According to the motor stator of the ninth aspect, the resin filling portion filled in the groove portion is prevented from coming off in the axial direction by the steel plate at the end portion. On the other hand, peeling in the axial direction can be prevented. According to the motor stator of the eleventh and twelfth aspects, the material of the covering member can be made preferable as the covering material of the stator, and a good stator can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional plan view of a main part showing a first embodiment of the present invention.

FIG. 2 is an overall plan view of a state where a stator core is covered with a covering member;

FIG. 3 is a longitudinal sectional side view.

FIG. 4 is an enlarged cross-sectional plan view of a groove portion.

FIG. 5 is a diagram showing a relationship between a material of a covering member and a physical property value.

FIG. 6 is a view corresponding to FIG. 4, showing a first modification of the groove.

FIG. 7 is a diagram corresponding to FIG. 4, showing a second modification of the groove portion;

FIG. 8 is a view corresponding to FIG. 4, showing a third modification of the groove.

FIG. 9 is a longitudinal sectional side view of a main part showing a second embodiment of the present invention.

FIG. 10 is an enlarged cross-sectional plan view of a main part.

FIG. 11 is a view corresponding to FIG. 1, showing a third embodiment of the present invention.

FIG. 12 is a cross-sectional plan view of a main part showing a fourth embodiment of the present invention.

FIG. 13 is a longitudinal sectional side view of a main part showing a fifth embodiment of the present invention.

FIG. 14 is a longitudinal sectional side view of a main part showing a sixth embodiment of the present invention.

FIG. 15 is a view corresponding to FIG. 1, showing a seventh embodiment of the present invention.

[Explanation of symbols]

1 is a stator core, 2 is a steel plate, 3 is a caulked portion, 4 is a yoke portion, 5 is a teeth portion, 6 is a groove portion, 6a is an opening portion, 6b.
Is an inner peripheral portion (extraction resistance portion), 7 is a covering member, 9 is a resin-filled portion, 10 is a gate, 14 is a mounting boss portion, 15 is a cylindrical portion, 20, 21, and 22 are grooves, 20a, 21a, and 22a.
Is an opening, 20b, 21b, 22b are inner peripheral portions (extraction resistance portions), 24 is a steel plate, 24a is a closing portion, 25 is a split core, 26 is a connecting portion, 29 is a groove portion, 30 is a resin filled portion, and 30 is a resin filled portion.
Reference numeral 1 denotes a resin filling portion, 35 denotes a covering member, 36 denotes a coil bobbin portion, 37 denotes a covering portion, 45 denotes a stator core, 46 denotes a yoke portion, 47 denotes a teeth portion, and 48 denotes a divided core.

Claims (12)

[Claims] 1. A stator core having a plurality of teeth on an outer peripheral portion or an inner peripheral portion of a yoke portion, and an insulating resin formed by molding so as to cover outer surfaces of the yoke portion and each of the teeth portions of the stator core. A covering member, provided on the yoke portion on the opposite side to the teeth portion, and at a substantially central portion between adjacent gates at the time of molding the covering member; A stator for a motor, comprising: a plurality of grooves extending in an axial direction; and a resin filling portion provided integrally with the covering member so as to be filled in each of the grooves. 2. A stator core having a plurality of teeth on an outer peripheral portion of a yoke portion, and a covering member made of an insulating resin provided by molding to cover outer surfaces of the yoke portion and each of the teeth portions of the stator core. A plurality of groove portions provided on the inner peripheral side of the yoke portion and at a substantially central portion between adjacent gates at the time of molding the covering member, and extending in the axial direction of the stator yoke; And a resin filling portion provided integrally with the covering member so as to be filled in each of the groove portions. 3. The motor stator according to claim 1, wherein the covering member is integrally provided with a mounting boss. 4. The motor stator according to claim 3, wherein a metal cylindrical portion is insert-molded on the mounting boss portion. 5. The motor stator according to claim 1, wherein the groove has a shape whose inside is wider than the opening. 6. The motor stator according to claim 1, wherein the groove has a shape having an escape resistance portion. 7. The gate according to claim 1, wherein the gate is disposed so as to be located on an extension of each of the teeth, and the groove is disposed substantially at the center between the adjacent teeth. Motor stator. 8. The stator yoke is formed by laminating a plurality of steel plates, and is provided with caulking portions at a plurality of locations, wherein the positions of the caulking portions and the groove portions are shifted in the circumferential direction. 3. The motor stator according to claim 1, wherein: 9. The stator yoke is formed by stacking a plurality of steel plates, and the steel plates located at both ends in the axial direction are:
The motor stator according to claim 1, wherein the stator is configured to cover an axial end of the groove. 10. The stator yoke is configured by connecting a plurality of divided cores divided in a circumferential direction, and a connecting portion between the divided cores also serves as a groove. Or the stator of the motor according to 2. 11. The material of the covering member is mainly composed of polyphenylene sulfide and mixed with glass, and the mixing ratio of the glass is 20 to 3 in weight ratio.
0% and the flexural modulus is 5000 to 10000
The motor stator according to claim 1 or 2, wherein a material having a physical property value of [MPa] and a melt viscosity of 150 to 200 [Pa · s] is used. 12. The material of the covering member is mainly composed of polyphenylene sulfide and mixed with glass, and the mixing ratio of the glass is 20 to 3 by weight.
0% and the flexural modulus is 5000 to 10000
[MPa], flow length is 15 to 50 [mm / 10 min]
2. A material showing physical property values of
Or the stator of the motor according to 2.