JP2002125353A - Electric motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the motor performance of an electric motor and to improve assemblability of the motor. SOLUTION: This electric motor has a rotor, incorporated rotatably in a housing and a stator placed coaxially with the rotor and incorporated incapable of rotation in the housing. The stator has a plurality of teeth 31a, arranged radially with the rotation center of the rotor as the center of the arrangement, a circular yoke 31b connecting the respective radial direction ends of the teeth 31a with each other, and a plurality of coils wound on the teeth 31a in slots S formed between the respective teeth 31a. The yoke 31b of the stator and the respective teeth 31a are integrally formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric motor having a rotor rotatably mounted on a housing and a stator coaxially disposed with respect to the rotor and non-rotatably mounted on the housing.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 9-215230 discloses a stator having a plurality of teeth radially arranged around a rotation axis of a rotor, and a circular yoke connecting radial ends of these teeth. An electric motor (electric motor) having a plurality of coils wound around the teeth at slots formed between the teeth is shown.

[0003]

In the stator disclosed in the above-mentioned publication, a plurality of teeth are formed separately from a yoke, and after winding a coil around each tooth, each tooth is attached to the yoke. A configuration for fixing is adopted. For this reason, the characteristics of the teeth tend to vary, which tends to cause an increase in cogging torque, which may degrade motor performance. Further, it is necessary to fix each tooth to the yoke, and there is room for improvement in assemblability. Therefore, an object of the present invention is to improve the motor performance or the assemblability of an electric motor.

[0004]

In order to achieve the above object, the present invention provides a rotor rotatably mounted on a housing, and a rotor coaxially disposed with respect to the rotor and non-rotatably mounted on the housing. A plurality of teeth provided with a stator to be assembled (which may be arranged on the outer periphery or the inner periphery of the rotor), wherein the stator is radially arranged around the rotation axis of the rotor;
In an electric motor having a circular yoke connecting radial ends of these teeth and a plurality of coils wound around the teeth at slots formed between the teeth, the yoke of the stator includes: It is characterized in that the teeth are integrally formed (the invention according to claim 1).

In this case, an insulator provided in each of the slots and interposed between each of the teeth and each of the coils is divided and formed in the axial direction of the motor (the invention according to claim 2). A pair of end insulators respectively fitted into both ends of the slot and through which a coil wire is inserted, and an elastically deformable intermediate insulator fitted into these end insulators at both ends and through which a coil wire is inserted. (Invention according to claim 3), forming a guide groove for guiding the coil in the insulator (invention according to claim 4), or a mold for molding at both axial ends of the insulator. It is desirable to form an engaging portion that engages with (the invention according to claim 5). In addition, an insulator interposed between each of the teeth and each of the coils is disposed in each of the slots, and a connecting portion that continuously connects the tips of the teeth in the circumferential direction is provided at predetermined axial intervals. (The invention according to claim 6).

Further, according to the present invention, there is provided a rotor rotatably mounted on a housing, and a stator coaxially disposed with respect to the rotor and non-rotatably mounted on the housing, wherein the stator is provided with the rotor. A plurality of teeth radially arranged around the rotation axis,
In an electric motor having a circular yoke connecting radial ends of these teeth and a plurality of coils wound around the teeth at slots formed between the teeth, three of the teeth are used. When winding the coil continuously, it was wound from the outer circumference of the tooth on one side to the inner circumference, then wound from the inner circumference of the center tooth to the outer circumference, and finally wound from the inner circumference of the other tooth to the outer circumference. That (claim 7
Of the present invention).

Further, according to the present invention, there is provided a rotor rotatably mounted on a housing, and a stator arranged coaxially with the rotor and non-rotatably mounted on the housing, wherein the stator is provided with A plurality of teeth radially arranged around the rotation axis,
In an electric motor having a circular yoke connecting the radial ends of these teeth and a plurality of coils wound around each of the teeth at slots formed between the teeth, the ends of the coils are It is characterized in that the terminal terminals are directly connected (the invention according to claim 8).

Further, according to the present invention, there is provided a rotor rotatably mounted on a housing, and a stator coaxially disposed with respect to the rotor and non-rotatably mounted on the housing, wherein the stator is formed of the rotor. A plurality of teeth radially arranged around the rotation axis,
In an electric motor having a circular yoke connecting radial ends of these teeth and a plurality of coils wound around the teeth at slots formed between the teeth, the outer peripheral surface of the rotor It is characterized in that a thin pipe covering the surfaces of the plurality of magnets to be assembled is fixed by caulking a part between the magnets (the invention according to claim 9).

Further, according to the present invention, there is provided a rotor rotatably mounted on the housing, and a stator coaxially disposed with respect to the rotor and non-rotatably mounted on the housing, wherein the stator is provided with the rotor. A plurality of teeth radially arranged around the rotation axis,
In an electric motor having a circular yoke connecting radial ends of these teeth and a plurality of coils wound around the teeth at slots formed between the teeth, the housing and the stator The sensor is made non-rotatable by key means, and a sensor that is attached to the housing and detects a rotational phase of the rotor with respect to the stator is positioned by the key means.
Of the present invention).

Further, in the present invention, a rotor rotatably mounted on the housing, a stator coaxially disposed with respect to the rotor and non-rotatably mounted on the housing, and rotation of the rotor with respect to the stator. In an electric motor provided with a sensor for detecting a phase, one end of the rotor is protruded from the housing by a predetermined amount in the axial direction, and the rotor is connected to a test device through a cutout provided in the protrusion so that torque can be transmitted. It is characterized by having such a configuration (the invention according to claim 11).

Further, according to the present invention, there is provided a rotor rotatably mounted on a housing, and a stator coaxially arranged with respect to the rotor and non-rotatably mounted on the housing, wherein the stator is provided with the rotor. A plurality of teeth radially arranged around the rotation axis,
In an electric motor having a circular yoke connecting radial ends of these teeth and a plurality of coils wound around the teeth at slots formed between the teeth, at a boundary between the phases. It is characterized in that the inner peripheral portions of the teeth are connected (the invention according to claim 12).

According to the present invention, there is provided an electric motor comprising a rotor rotatably mounted on a housing and a stator arranged coaxially with the rotor and non-rotatably mounted on the housing. A sensor for detecting a rotational phase of the rotor and the stator, a back electromotive force sensor for detecting a back electromotive voltage of the motor, and a calculating means for calculating an offset amount based on outputs from these two sensors. (Claim 1
3).

According to the present invention, there is provided an electric motor comprising a rotor rotatably mounted on a housing and a stator arranged coaxially with the rotor and non-rotatably mounted on the housing. A magnetic encoder is employed as a sensor for detecting the rotational phase of the rotor and the stator, and an absolute sensor unit and an incremental sensor unit are arranged substantially linearly in the axial direction in the encoder. (14th invention).

Further, according to the present invention, there is provided a rotor rotatably mounted on the housing, and a stator coaxially disposed with respect to the rotor and non-rotatably mounted on the housing, wherein the stator is formed of the rotor. A plurality of teeth radially arranged around the rotation axis,
In an electric motor having a circular yoke connecting radial ends of these teeth and a plurality of coils wound around the teeth at slots formed between the teeth, the electric motor is located between the teeth. It is characterized in that a part of the yoke is protruded by a predetermined amount in the direction in which the teeth extend (the invention according to claim 15).

[0015]

In the electric motor according to the present invention (the invention according to claim 1), since each tooth is formed integrally with the yoke, the characteristics of each tooth are less likely to vary, and the cogging torque is reduced. The increase can be suppressed, and the performance of the motor can be improved. In addition, when the insulator provided in each slot and interposed between each tooth and each coil is divided and formed in the motor axis direction (in the case of the invention according to claim 2), in addition to the effects described above, In addition, assemblability of the insulator into each slot can be improved.

Further, the electric motor according to the present invention (claim 3)
In the invention according to the present invention, a stator is formed by assembling a pair of end insulators and an intermediate insulator into each slot, inserting a coil wire, and molding the coil with a resin. . By the way, since the insulator attached to each slot is divided in the axial direction, the insulator can be easily attached to the slot. Further, when the coil is molded with resin, both ends of the intermediate insulator are elastically deformed by the molding pressure and are brought into close contact with the inner surface of the end insulator to prevent leakage of the resin. Thereby, the resin does not leak to the peripheral surface of the stator,
The gap between the rotor and the stator can be set narrow, and the motor performance can be improved.

Further, the electric motor according to the present invention (Claim 4)
In the invention according to (1), since the guide groove for guiding the coil is formed in the insulator attached to each slot, the coil can be wound stably, and the assemblability can be improved. Further, in a case where engaging portions for engaging with a mold for molding are formed at both ends in the axial direction of the insulator (in the case of the invention according to claim 5), the resin is used for molding with the insulator and the mold for molding. Leakage between molds can be prevented, and the gap between the rotor and stator can be set narrow,
The motor performance can be improved.

Further, the electric motor according to the present invention (claim 6)
In the invention according to the present invention, since the connecting portions for continuously connecting the tips of the teeth in the circumferential direction are provided at predetermined axial intervals, the radial direction of the insulator interposed between each tooth and each coil is provided. It is possible to prevent protrusion (protrusion in the radial direction through a gap formed between the tips of the teeth), to set a narrow gap between the rotor and the stator, and to improve motor performance. it can.

The electric motor according to the present invention (claim 7)
In the invention according to (1), when winding the coil continuously around three of the teeth, after winding from the outer circumference to the inner circumference of one of the teeth, the coil is wound from the inner circumference to the outer circumference of the central tooth, and finally Since the teeth on the other side are wound from the inner circumference to the outer circumference, it is possible to increase the number of coil turns by effectively utilizing the outer circumference part (the space is larger than the inner circumference part) between the teeth. Thus, the motor performance can be improved.

Further, the electric motor according to the present invention (claim 8)
In the invention according to the present invention, since the terminal terminal is directly connected to the end of the coil, the position of the terminal terminal can be arbitrarily changed by bending the end of the coil, and the degree of freedom in setting the terminal terminal is increased. Thus, the assembling property can be improved.

The electric motor according to the present invention (claim 9)
In the invention according to the invention), since the thin pipe covering the surfaces of the plurality of magnets mounted on the peripheral surface of the rotor is fixed by caulking a part between the magnets, the diameter and size of the rotor are controlled by the thickness of the magnet and the thickness of the thin pipe. The thickness can be easily adjusted, the gap between the rotor and the stator can be easily managed, and the motor performance can be stabilized.

Further, the electric motor according to the present invention (Claim 1)
0), the housing and the stator are made non-rotatable by the key means, and the sensor mounted on the housing and detecting the rotational phase of the rotor with respect to the stator is positioned by the key means. By using the key means, a sensor for detecting the rotational phase of the rotor can be positioned and fixed with respect to the housing. Therefore, the sensor can be easily and inexpensively and accurately positioned with respect to the stator, the rotation phase of the rotor with respect to the stator can be accurately detected, and the motor performance can be sufficiently exhibited.

Further, the electric motor according to the present invention (Claim 1)
In the invention according to the first aspect), since one end of the rotor is axially protruded from the housing by a predetermined amount and is connected to the test device through a cutout provided in the protruding portion so as to be able to transmit torque, the motor It is possible to evaluate the performance of a single unit,
Offset adjustment of a sensor mounted on the housing and detecting the rotation phase of the rotor with respect to the stator can be easily performed by the motor alone, and variations in motor performance can be suppressed.

Further, the electric motor according to the present invention (Claim 1)
In the invention according to (2), since the tips of the teeth are connected at the boundary between the coil units of each phase, that is, at a portion where the magnetic flux change is small and the back electromotive voltage is small, it is possible to suppress the generation of noise due to the back electromotive voltage. At the same time, the cogging torque can be reduced, and the motor performance can be improved.

Further, the electric motor according to the present invention (Claim 1)
In the invention according to the third aspect), a sensor that is attached to the housing and detects the rotational phase of the rotor and the stator, a back electromotive force sensor that detects the back electromotive force of the motor, and an offset based on the outputs from these two sensors. Since the calculation means for calculating the amount is provided, the offset amount of the sensor can be easily obtained electrically, and the detection value of the sensor can be electrically corrected based on this. Therefore, there is no need to mechanically adjust the offset of the sensor with respect to the housing, and the workability of assembly can be improved.

The electric motor according to the present invention (Claim 1)
In the invention according to the fourth aspect), a magnetic encoder is employed as a sensor that is attached to the housing and detects the rotational phase of the rotor and the stator. In this encoder, the absolute sensor unit and the incremental sensor unit are substantially linear in the axial direction. , The detection sensitivity of the sensor can be easily adjusted.

Further, the electric motor according to the present invention (Claim 1)
In the invention according to the fifth aspect), since a part of the yoke located between the teeth is protruded by a predetermined amount in the direction in which the teeth extend, it is possible to suppress a decrease in the space of the winding wire and increase the rigidity of the yoke.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. 1 and 2 show an embodiment in which the electric motor according to the present invention is employed in a steering device for a vehicle. The electric motor according to this embodiment includes a cylindrical rotor 20 rotatably and axially immovably mounted on a housing 10 via ball bearings 91 and 92, and a housing arranged coaxially around the outer periphery of the rotor 20. The motor housing 11 includes a stator 30 that is non-rotatably (integrally) mounted to the motor housing 11 and a sensor 40 that detects the rotational phase of the rotor 20. ) And control signals (not shown) based on detection signals from the sensor 40 and the like.

The housing 10 includes a motor housing 11
The gear housing 12 is configured to support a pinion shaft and a steering rack shaft (not shown). The steering rack shaft is coaxially mounted in the rotor 20 via a ball screw mechanism (not shown) so that the rotation of the rotor 20 applies an axial steering assisting force. Has become.

As shown in FIGS. 1 and 3, the rotor 20 has a shaft body 21 made of a magnetic material and formed into a stepped cylindrical shape.
16 permanent magnets 22 arranged and fixed at equal intervals on the outer periphery of the shaft main body 21, a thin pipe 23 (a non-magnetic material such as stainless steel or aluminum) covering these permanent magnets 22 from the outer periphery, A stepped cylindrical pipe stopper 24 fixed to the outer periphery of the shaft main body 21 to prevent the thin pipe 23 from coming off.
(Material is metal, non-metal, magnetic material, non-magnetic material)
It is constituted by. The pipe stopper 24
It is also possible to extend a part of the rotor-side member 42 of the sensor 40 and use it as a substitute (substitute). In this case, the number of parts can be reduced.

The shaft main body 21 protrudes from the left end of the motor housing 11 in the axial direction by a predetermined amount, and a notch 21b provided in the protruding portion 21a forms a rotating shaft of a test device (motor performance evaluation test device not shown). Is configured to be capable of transmitting torque. The mounting surface of the electric motor shown in FIG. 1 to the test device is the left end surface of the motor housing 11 in FIG.

Each of the permanent magnets 22 has a shape that is long in the axial direction, and is formed in an arc shape that is convex toward the inner periphery (the S pole is skipped one by one) toward the inner periphery. The side (the N pole is alternately set as the N pole) is formed in an arc shape centered on the rotation center of the rotor 20. The thin pipe 23
It is a pipe for preventing magnet scattering, and is fixed to the outer periphery of the permanent magnet 22 by caulking a part between the permanent magnets 22. Note that the thin pipe 23 and the pipe stopper 24 may have an integrated structure molded with resin.

As shown in FIGS. 1 and 4, the stator 30 has a cylindrical core 31, a plurality of (18) coils 32 wound around the core 31, a core 31 and a coil 32.
An insulator 33 interposed therebetween, a coil connection tool (bus bar) 34 for connecting the end of each coil 32, and an energizing terminal 35 connected to the coil connection tool 34 are provided. And are molded and integrated with a resin 36 having electrical insulation.

The core 31 is, as shown in FIGS.
The electromagnetic steel sheet is punched into a predetermined shape (the shape shown in FIG. 5) and then laminated in the axial direction to form an integrated structure.
Eighteen teeth 31a radially arranged around the rotation axis of the rotor 20 and a circular yoke 31b connecting radial outer ends of these teeth 31a are provided, and each tooth 31a and the yoke 31b are integrated. Is formed. Each tooth 31a has a magnetic pole portion 31a1 extending in the circumferential direction on the inner circumferential side, and forms a slot S extending in the axial direction for winding the coil 32. In addition, circular concave and convex fitting portions 31c and 31d are formed at the base end and the distal end of each tooth 31a, and electromagnetic steel plates are integrally laminated by fitting these. .

As shown in FIGS. 8 to 11, three coils 32 continuous in the circumferential direction constitute one coil unit (U1).
, V1, W1, U2, V2, and W2 phases), and is formed continuously with one coil wire, and the 18 coils 32 are composed of six coil wires. It is desirable that the tip of each coil wire is sharply sharpened in order to enhance the winding property, assembling property, and reliability on the core 31 and the coil connection tool 34, and at that time, the tip is sharply sharpened using a dedicated jig. Alternatively, the coil wire may be thinned by being pulled in the axial direction, and then cut and sharpened.

As shown in FIG. 11, each of the coil units is wound in the order of 1 to 8 from the outer periphery of the left tooth 31a to the inner periphery, and then 9 to 15 from the inner periphery of the center tooth 31a to the outer periphery. Roll it up and finally the right tooth 31a
Are wound in the order of 16 to 24 from the inner circumference to the outer circumference. If the outer periphery 15 of the central tooth 31a is wound around the outer periphery 24 of the right tooth 31a, it cannot be wound next on the outer periphery 22 of the right tooth 31a, and the number of turns of the coil 32 is reduced. I will.

As shown in FIGS. 8 and 12 to 16, the insulator 33 has a pair of end insulators 33a attached to the axial ends of the core 31, and two end insulators 33a inside the end insulators 33a. An intermediate insulator 33b is fitted and fitted, and is formed into three parts in the motor axis direction. Each end insulator 33a is shown in FIG.
As shown in FIG. 15, the through hole 3 through which the coil wire is inserted.
3a1, a projection 33a2 fitted into a notch 31e formed at an end of the core 31, a guide groove 33a3 for guiding each coil 32, and three notches 33a4 are formed, and correspond to the through holes 33a1. A cylindrical portion 33a5 is formed. As shown in FIG. 16, the intermediate insulator 33b is formed by bending an elastically deformable thin plate-shaped insulator material into a shape of a slot S (a shape through which a coil wire is inserted) to form a cylindrical shape. The portion is located at the center of the outer peripheral side of the slot S.

As shown in FIGS. 1, 4, 8, and 9, the coil connecting member 34 is a holder 34 made of an insulating resin.
a and each connecting piece 34 for connecting the end of each coil unit
b, the holder 34a has an end insulator 33
a leg portion 34a1 that fits into the notch 33a4 of FIG.
Each connection piece 34b is formed with a flat plate portion 34b1 to which each connection piece 35a of the conducting terminal 35 is connected. The flat plate portion 34b1 of each connection piece 34b and each connection piece 35a of the energizing terminal 35 are joined by resistance welding before being molded with the resin 36.

The energizing terminal 35 is fixed to the housing 10 in advance by screwing (see FIG. 2), and the core 31, the coil 32, the insulator 33, and the coil connector 34 of the stator 30 are in the state shown in FIGS. By being incorporated into the motor housing 11 as shown in FIG.
The respective flat plate portions 34b1 are in contact with each other. At this time, a key 50 shown by a virtual line in FIG. 1 is used for positioning the stator 30 with respect to the motor housing 11 (positioning in the circumferential direction). The key 50 is used for the housing-side member 41 of the sensor 40 (see FIGS. 1 and 17).
Can be used as a reference when assembling to the motor housing 11. When positioning the stator 30 and the housing-side member 41 of the sensor 40 with respect to the motor housing 11 in this manner, the positioning of the sensor 40 with respect to the rotor 20 with respect to the rotor 20 is performed using a non-magnetic key ( It is desirable to perform the same in the same way (not shown).

As shown in FIG. 18, the resin 36 is filled and solidified in a state in which a mold 60 for molding is fitted on the inner periphery of the stator 30. As shown, the stator 30 is integrated with the motor housing 11. Mold 60 for molding
Has a tapered surface 61 at both ends in the axial direction of the insulator 33, that is, at a portion engaged with the inner periphery of the end of the end insulator 33a, and the resin 36 leaks to the inner periphery of the end insulator 33a during molding. Is preventing that. The injection port (gate not shown) of the resin 36 is desirably provided at a position where the molding pressure does not directly act on the core 31, and at a position substantially in the center of the slot S where the coil 32 does not hinder resin injection. Is desirable.

The sensor 40 includes a housing side member 41 positioned and fixed to the motor housing 11 and a rotor 20.
The rotor 20 is constituted by a rotor side member 42 positioned and fixed to the motor housing 11.
And the phase of stator 30 (rotor 2 with respect to stator 30)
(A rotation phase of 0) is detected, and a detection signal is output to a control device (not shown).

If the offset value of the sensor 40 with respect to the motor unit is detected in advance and is written in the sensor 40 in the form of a trimming resistor or the like, the offset value is controlled from the sensor 40 by the voltage level. It can be output to a device (not shown). In this case, there is no need to write the offset value in the control device (not shown). Even if the control device (not shown) changes, the offset value is accurately sent to the control device (not shown), and the predetermined torque is obtained. Can be generated.

The electric motor configured as described above can be used in the following steps, ie, a step of winding each coil 32 around the core 31, a step of assembling the coil connecting member 34 to each coil 32, and a motor of the stator 30. It is manufactured through a molding process for the housing 11, a process for assembling the housing side member 41 of the sensor 40 to the motor housing 11, a process for assembling the rotor 20 to the housing 10, and the like.

In the step of winding each coil 32 around the core 31, prior to winding each coil 32, each end insulator 33 a is attached to both ends of the core 31 in the axial direction, and then each intermediate insulator 33 b is wound. Each of the 18 intermediate insulators 33b is fitted such that both ends are fitted into the cylindrical portion 33a5 of each end insulator 33a.
Then, each coil 32 is sequentially wound in the order shown in FIG. 11 to form a coil unit.

In the step of assembling the coil connection device 34 to each coil 32, the coil connection device 34 fits each leg 34a1 into each notch 33a4 of the end insulator 33a in accordance with each coil unit wound around the core 31. By being fitted together, they are assembled in the axial direction, and the ends (coil wires) of the respective coil units are fixed by caulking to the corresponding portions of the respective connection pieces 34b, and the stator sub-assembly shown in FIGS. Is formed.

In the step of molding the stator 30 into the motor housing 11, prior to the molding, FIG.
10 is positioned and fixed to the motor housing 11 using the key 50, and the energizing terminals 35 are assembled to the motor housing 11 from the outer periphery. Each connecting piece 35 of the flat plate portion 34b1 of 34b and the energizing terminal 35
a is joined by resistance welding, and then set in a mold 60 for molding and molded with the resin 36. The injection of the resin 36 is performed from the right side to the left side in FIG. 1 and from the inner circumference to the outer circumference.

The housing-side member 41 of the sensor 40
In the step of assembling to the motor housing 11, the housing side member 41 is positioned to the motor housing 11 with respect to the key 50 (see the phantom line in FIG. 1) in which the stator sub-assembly is positioned to the motor housing 11. Can be Before or after this step, the ball bearing 91 is assembled to the motor housing 11.

In the process of assembling the rotor 20 to the housing 10, the rotor side member 42 of the sensor 40 is positioned and assembled at the right end of the rotor 20, and the ball bearing 92 is mounted.
Is mounted, the rotor 20 is mounted on the gear housing 12 via the ball bearing 92, and then the stator 30 is mounted.
The motor housing 11 with the assembled components is inserted from left to right of the rotor 20 to connect the motor housing 11 and the gear housing 12 with bolts (not shown).

In the electric motor of the present embodiment manufactured as described above, each tooth 31a is connected to the yoke 31b.
Since the teeth 31a are formed integrally with each other, the characteristics of the teeth 31a are unlikely to vary, the increase in cogging torque can be suppressed, and the motor performance can be improved.

An insulator 33 disposed in each slot S and interposed between each tooth 31a and each coil 32 is provided with a pair of end insulators 33a attached to both ends of the core 31 and each slot S. Since it is constituted by 18 intermediate insulators 33b to be assembled therein and is divided and formed in the axial direction of the motor, it is possible to easily assemble the insulator 33 into each slot S.

When molding each of the coils 32 and the like with the resin 36, both ends of the intermediate insulator 33b are elastically deformed by the molding pressure, so that the end insulator 3
3a is pressed into close contact with the inner surface to prevent resin leakage. Thereby, the resin 36 does not leak to the inner peripheral surface of the stator 30, the gap between the rotor 20 and the stator 30 can be set narrow, and the motor performance can be improved. In addition, the overlapping portion of the intermediate insulator 33b is also brought into close contact with each other by the molding pressure to prevent the resin from leaking.

In the electric motor according to the present embodiment, since the guide groove 33a3 for guiding the coil 32 is formed in the end insulator 33a of the insulator 33 attached to each slot S, the coil 32 can be wound stably. And improve the assemblability. In addition, since the engagement portions that engage with the mold 60 for molding are formed at both ends in the axial direction of the insulator 33, the resin 36 leaks to the inner peripheral side through the space between the insulator 33 and the mold 60 for molding during molding. Can be prevented, the gap between the rotor 20 and the stator 30 can be set narrow, and the motor performance can be improved.

In the electric motor according to the present embodiment, when the coil 32 is continuously wound around the three teeth 31a, as shown in FIG. After winding, the center teeth 3
Wrap from the inner circumference to the outer circumference of 1a, and finally the teeth 3 on the other side
Since the inner periphery of the coil 1a is wound from the inner periphery to the outer periphery, the outer peripheral portion between the teeth 31a (the space is larger than the inner peripheral portion) can be effectively utilized, and the number of turns of the coil 32 can be increased. The motor performance can be improved.

In the electric motor of the present embodiment, the thin pipe 23 covering the surface of the plurality of permanent magnets 22 attached to the outer peripheral surface of the rotor 20 is fixed by caulking a part between the magnets. Diameter can be easily controlled by the thickness of the permanent magnet 22 and the thickness of the thin pipe 23, the gap between the rotor 20 and the stator 30 can be easily controlled, and the motor performance can be stabilized. Can be.

In the electric motor according to the present embodiment, the motor housing 11 and the stator 30 are non-rotatably positioned by the key 50, and are mounted on the motor housing 11 to detect the rotation phase of the rotor 20 with respect to the stator 30. The housing side member 41 of the key 5
0, the stator 30 can be non-rotatably positioned and fixed to the motor housing 11 by the key 50, and the housing-side member 41 of the sensor 40 is
Can be positioned and fixed with respect to. Therefore,
The sensor 40 can be easily and inexpensively and accurately positioned with respect to the stator 30, the rotation phase of the rotor 20 with respect to the stator 30 can be accurately detected, and the motor performance can be sufficiently exhibited. is there.

In the electric motor of the present embodiment, one end of the rotor 20 is projected from the housing 10 in the axial direction by a predetermined amount, and the notch 21 provided in the projection 21a is provided.
Since the motor is configured to be connected to the rotating shaft of the test apparatus so as to be able to transmit torque at b, it is possible to evaluate the performance of the motor alone and detect the rotational phase of the rotor 20 with respect to the stator 30 by being assembled to the housing 10. The offset adjustment and the like of the sensor 40 can be easily performed by the motor alone, and variation in motor performance can be suppressed.

In the above embodiment, FIGS.
As shown by, the tip (inner peripheral end) of each tooth 31a
Are formed discontinuously in the circumferential direction, and each slot S is continuously opened on the inner circumferential side. However, as shown by a virtual line in FIG. In the case where the connecting portions 31a2 that are continuously connected with each other are provided at predetermined intervals in the axial direction (when the connecting portions 31a2 are provided on electromagnetic steel sheets stacked for a predetermined number of sheets), each tooth 31a and each coil The intermediate insulator 33b interposed between the teeth 32 can be prevented from protruding in the radial direction (protruding radially inward through a gap formed between the tips of the teeth 31a). Can be set narrow, and the motor performance can be improved.

In the above embodiment, the insulator 33 is constituted by a pair of end insulators 33a attached to both ends of the core 31 and 18 intermediate insulators 33b attached in each slot S (2). However, as shown in FIG. 19, the cylindrical portion 33a5 of the end insulator 33a is formed to be longer by a predetermined amount in the axial direction (formed to be approximately half the axial length of the core 31). In addition, it is also possible to alternately form the distal end portion as a solid line shape and an imaginary line shape that are oblique in the radial direction (alternately, the shape can be implemented in an oblique shape in the circumferential direction). In this case, when assembling the pair of end insulators 33 a to the core 31, the phases are shifted vertically by one slot, so that the insulators 33 can be composed of one kind and two pieces, so that the number of parts is reduced. Thus, cost reduction and productivity improvement can be achieved.

In the above embodiment, the coil connector 34 is used to connect the end of each coil 32 and each connection piece 35a of the current-carrying terminal 35. However, as shown in FIG. A terminal terminal 39 is provided at the end of each coil 32.
Are directly connected, and this terminal terminal 39 is
5 may be connected to each connection piece 35a. In this case, it is possible to arbitrarily change the position of the terminal terminal 39 by bending the end of the coil 32, so that the degree of freedom in setting the terminal terminal 39 can be improved and the assembling property can be improved. Can be done.

In practicing the present invention, each phase (U1
Phase, V1, W1, U2, V2, W2) coil unit boundaries (C1, C2, C3, C in FIG. 10)
4, C5, C6), that is, when the tip of the tooth 31a is connected to a portion where the magnetic flux change is small and the back electromotive voltage is small, it is possible to suppress the generation of noise due to the back electromotive voltage and to reduce the cogging torque. And the motor performance can be improved.

In practicing the present invention, the sensor 40
In addition, a back electromotive force sensor (not shown) for detecting a back electromotive voltage of the electric motor, and a calculation means (not shown) for calculating an offset amount based on outputs from both sensors
Is provided, the offset of the sensor 40 can be easily obtained electrically, and the sensor 40
Can be electrically corrected. Therefore, in this case, the sensor 40 is connected to the motor housing 11.
Therefore, it is not necessary to mechanically adjust the offset, thereby improving the assembling workability.

In implementing the present invention, the sensor 40
Instead of the magnetic encoder 1 shown in FIGS.
It is also possible to adopt and implement 40. The encoder 140 includes a housing-side member 141 mounted on the motor housing 11 and a rotor-side member 142 (drum 142a and magnet 14) mounted on the rotor 20 side.
2b), the magnet 142b of the rotor side member 142 has an incremental phase (an INC phase of 108 poles each of N and S poles) and an absolute phase (an INC phase of 108 poles as shown in FIG. 23). 8 poles each for N and S poles /
(U phase, V phase, W phase) are axially displaced and magnetized.

For this reason, when an electric motor is configured by employing the above-described encoder 140, the absolute phase (U-phase, U-phase,
Since the V phase and the W phase) and the incremental phase (INC phase) functioning as an incremental sensor are arranged substantially linearly in the axial direction, the detection sensitivity of the sensor can be easily adjusted.

In implementing the present invention, as shown in FIG. 24, the yoke 31b located between the teeth 31a
When a part of the yoke 31b is protruded by a predetermined amount in the extending direction (inner circumferential direction) of the teeth 31a, the rigidity of the yoke 31b is increased by reducing the space of the winding (reducing the space for winding the coil 32). be able to.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of an electric motor according to the present invention.

FIG. 2 is a plan view of the electric motor shown in FIG.

FIG. 3 is a vertical sectional side view of a main part of the rotor shown in FIG. 1;

FIG. 4 is a longitudinal sectional view of the motor housing and the stator shown in FIG.

FIG. 5 is a front view of the core shown in FIGS. 1 and 4;

FIG. 6 is a side view of the core shown in FIGS. 1 and 4;

FIG. 7 is an enlarged front view showing a part of FIG. 2;

8 is a cross-sectional view taken along line AA of FIG. 9 showing a relationship among a core, a coil, an insulator, and a coil connector in the stator shown in FIGS. 1 and 4;

9 is a left side view of the assembly shown in FIG.

FIG. 10 is an enlarged cross-sectional view of the assembly shown in FIG. 8, taken along line BB.

FIG. 11 is an enlarged view showing the winding order of the coil shown in FIG.

FIG. 12 is a front view of the end insulator alone shown in FIG. 8;

FIG. 13 is a rear view of the end insulator alone shown in FIG. 8;

FIG. 14 is an enlarged front view showing a part of FIG. 12;

FIG. 15 is a rear view showing a part of FIG. 13 in an enlarged manner.

FIG. 16 is a view showing an intermediate insulator assembled between both end insulators shown in FIG. 8;

FIG. 17 is a front view of the sensor shown in FIG. 1;

FIG. 18 is an explanatory diagram of a process when the stator constituent member is resin-molded in the motor housing.

FIG. 19 is a partial sectional view showing a modified embodiment of the insulator.

FIG. 20 is a diagram showing an embodiment in which a terminal terminal is directly connected to an end of a coil.

FIG. 21 is a side view of a magnetic encoder that can be employed instead of the sensor shown in FIG. 1;

FIG. 22 is a plan view of the magnetic encoder shown in FIG.

23 is a diagram showing a positional relationship of magnetized tracks provided on the outer peripheral surface of a rotor side member of the magnetic encoder shown in FIG.

FIG. 24 is a partial view showing a modified embodiment of the yoke in the core.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Housing, 11 ... Motor housing, 12 ... Gear housing, 20 ... Rotor, 21 ... Shaft main body, 21a ...
Projection, 21b Notch, 22 Permanent magnet, 23 Thin pipe, 24 Pipe stopper, 30 Stator, 31
... core, 31a ... teeth, 31a2 ... connecting part provided in the teeth, 31b ... yoke, 32 ... coil, 33 ... insulator, 33a ... end insulator, 33a3 ...
Guide groove provided in the end insulator, 33b intermediate insulator, 34 coil connection tool, 35 energizing terminal, 3
6 ... Molding resin, 39 ... Terminal terminal, 40 ...
Sensor, 41: Housing side member, 42: Rotor side member, 50: Key, 60: Mold for molding, 91, 9
2 ... Ball bearing, S ... Slot.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02K 3/12 H02K 3/12 5H621 3/34 3/34 C 5H622 3/50 3/50 A 5/22 5/22 11/00 11/00 CF term (reference) 5H002 AA01 AA08 AB04 AB07 AC01 AC03 AC08 AC09 AE06 5H603 AA03 AA04 AA09 BB01 BB09 BB12 CA01 CA05 CB02 CB04 CB12 CB20 CB24 CB26 CC03 CC17 CD02 CD21 CD28 CE01 FE01 FA16 5H604 AA08 BB01 BB10 BB14 CC01 CC05 CC13 DA14 DB26 PB03 PC03 PE06 QB03 QB16 5H605 BB05 BB10 CC01 CC02 CC06 CC09 DD05 EB10 EC01 GG02 GG03 GG04 GG06 GG18 5H611 AA01 BB01 BB07 CA01 BB02 A0101 PP12 PP18

Claims (15)

[Claims] 1. A rotor rotatably mounted on a housing, and a stator arranged coaxially with the rotor and non-rotatably mounted on the housing, wherein the stator is centered on a rotation axis of the rotor. A plurality of teeth radially arranged as, a circular yoke connecting radial ends of these teeth, and a plurality of coils wound around each of the teeth at slots formed between the teeth. An electric motor comprising: the yoke of the stator; and the teeth are integrally formed. 2. The electric motor according to claim 1, wherein an insulator disposed in each of the slots and interposed between each of the teeth and each of the coils is divided and formed in the axial direction of the motor. Electric motor. 3. An electric motor according to claim 2, wherein said insulators are respectively fitted to both ends of said slot, and a pair of end insulators through which a coil wire is inserted, and both ends inside said end insulators. An electric motor comprising an elastically deformable intermediate insulator into which a coil wire is inserted and inserted. 4. The electric motor according to claim 2, wherein a guide groove for guiding the coil is formed in the insulator. 5. The electric motor according to claim 2, wherein an engaging portion for engaging a mold for molding is formed at both axial ends of the insulator. 6. The electric motor according to claim 1, wherein an insulator interposed between each of the teeth and each of the coils is disposed in each of the slots, and a tip of each of the teeth is continuously arranged in a circumferential direction. An electric motor characterized in that connecting portions for connecting to the motor are provided at predetermined axial intervals. 7. A rotor rotatably mounted on a housing, and a stator arranged coaxially with the rotor and non-rotatably mounted on the housing, wherein the stator is centered on a rotation axis of the rotor. A plurality of teeth radially arranged as, a circular yoke connecting radial ends of these teeth, and a plurality of coils wound around each of the teeth at slots formed between the teeth. In the electric motor having three teeth, the coils are wound continuously from the outer circumference to the inner circumference of one of the teeth, and then wound from the inner circumference to the outer circumference of the central tooth. An electric motor characterized in that the teeth are wound from the inner circumference to the outer circumference. 8. A rotor rotatably mounted on a housing, and a stator arranged coaxially with the rotor and non-rotatably mounted on the housing, wherein the stator is centered on a rotation axis of the rotor. A plurality of teeth radially arranged as, a circular yoke connecting radial ends of these teeth, and a plurality of coils wound around each of the teeth at slots formed between the teeth. An electric motor having a terminal connected directly to an end of the coil. 9. A rotor rotatably mounted on a housing, and a stator arranged coaxially with the rotor and non-rotatably mounted on the housing, wherein the stator is centered on a rotation axis of the rotor. A plurality of teeth radially arranged as, a circular yoke connecting radial ends of these teeth, and a plurality of coils wound around each of the teeth at slots formed between the teeth. An electric motor comprising: a thin pipe covering a surface of a plurality of magnets attached to a peripheral surface of the rotor, the thin pipe being fixed by caulking a part between the magnets. 10. A rotor rotatably mounted on a housing, and a stator arranged coaxially with the rotor and non-rotatably mounted on the housing, wherein the stator is centered on a rotation axis of the rotor. A plurality of teeth radially arranged as, a circular yoke connecting radial ends of these teeth, and a plurality of coils wound around each of the teeth at slots formed between the teeth. An electric motor, wherein the housing and the stator are made non-rotatable by key means, and a sensor attached to the housing and detecting a rotation phase of the rotor with respect to the stator is positioned by the key means. motor. 11. A rotor rotatably mounted on a housing, a stator arranged coaxially with the rotor and non-rotatably mounted on the housing, and a sensor for detecting a rotation phase of the rotor with respect to the stator. An end portion of the rotor is axially protruded from the housing by a predetermined amount, and the rotor is configured to be connected to a test device through a notch provided in the protruding portion so that torque can be transmitted. An electric motor characterized by the following. 12. A rotor rotatably mounted on a housing, and a stator arranged coaxially with the rotor and non-rotatably mounted on the housing, wherein the stator is centered on a rotation axis of the rotor. A plurality of teeth radially arranged as, a circular yoke connecting radial ends of these teeth, and a plurality of coils wound around each of the teeth at slots formed between the teeth. An electric motor comprising: an end portion of the teeth connected to a boundary between coil units of each phase. 13. An electric motor comprising a rotor rotatably mounted on a housing and a stator coaxially disposed with respect to the rotor and non-rotatably mounted on the housing. A sensor for detecting a rotation phase of the rotor and the stator,
An electric motor, comprising: a back electromotive force sensor for detecting a back electromotive force of a motor; and a calculating means for calculating an offset amount based on outputs from both sensors. 14. An electric motor comprising: a rotor rotatably mounted on a housing; and a stator coaxially disposed with respect to the rotor and non-rotatably mounted on the housing, the electric motor being mounted on the housing. An electric motor, wherein a magnetic encoder is employed as a sensor for detecting a rotation phase of the rotor and the stator, and an absolute sensor unit and an incremental sensor unit are arranged substantially linearly in the axial direction in the encoder. 15. A rotor rotatably mounted on a housing, and a stator arranged coaxially with the rotor and non-rotatably mounted on the housing, wherein the stator is centered on a rotation axis of the rotor. A plurality of teeth radially arranged as, a circular yoke connecting radial ends of these teeth, and a plurality of coils wound around each of the teeth at slots formed between the teeth. An electric motor comprising: a part of the yoke located between the teeth protruding a predetermined amount in a direction in which the teeth extend.