WO2015194614A1 - Motor, and electric power steering device and vehicle mounted with same - Google Patents

Motor, and electric power steering device and vehicle mounted with same Download PDF

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Publication number
WO2015194614A1
WO2015194614A1 PCT/JP2015/067550 JP2015067550W WO2015194614A1 WO 2015194614 A1 WO2015194614 A1 WO 2015194614A1 JP 2015067550 W JP2015067550 W JP 2015067550W WO 2015194614 A1 WO2015194614 A1 WO 2015194614A1
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WIPO (PCT)
Prior art keywords
motor
rotational position
position sensor
electric power
resolver stator
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PCT/JP2015/067550
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French (fr)
Japanese (ja)
Inventor
梢 中村
稔晃 浅田
菊地　祐介
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日本精工株式会社
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Publication of WO2015194614A1 publication Critical patent/WO2015194614A1/en

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K29/00—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
    • H02K29/06—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices
    • H02K29/12—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices using detecting coils using the machine windings as detecting coil
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
    • H02K11/20—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection for measuring, monitoring, testing, protecting or switching
    • H02K11/21—Devices for sensing speed or position, or actuated thereby
    • H02K11/225—Detecting coils
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/10—Structural association with clutches, brakes, gears, pulleys or mechanical starters
    • H02K7/116—Structural association with clutches, brakes, gears, pulleys or mechanical starters with gears
    • H02K7/1163—Structural association with clutches, brakes, gears, pulleys or mechanical starters with gears where at least two gears have non-parallel axes without having orbital motion
    • H02K7/1166—Structural association with clutches, brakes, gears, pulleys or mechanical starters with gears where at least two gears have non-parallel axes without having orbital motion comprising worm and worm-wheel

Definitions

  • a recess is formed on the bottom of a motor yoke (case) so that a rotational position sensor such as a resolver can be inserted from the outside, and a motor having a structure in which the concave wall surface can be used for introduction of the rotational position sensor and the motor mounted thereon
  • An electric power steering device mounted on a vehicle applies an assist force by a motor (for example, a brushless motor) to a steering system of the vehicle based on a current command value calculated based on at least a steering torque, and includes a bridge circuit. Drive controlled by an inverter.
  • an electric power steering device as a device in which a motor is mounted on the drive unit, and the electric power steering device applies a steering assist force (assist force) to the steering mechanism of the vehicle by the rotational force of the motor.
  • the driving force of the motor controlled by the electric power supplied from the motor is applied to the steering shaft or the rack shaft by a transmission mechanism such as a gear.
  • a conventional electric power steering apparatus performs feedback control of the motor current in order to accurately generate the torque of the steering assist force.
  • the motor applied voltage is adjusted so that the difference between the steering assist command value (current command value) and the motor current detection value is small.
  • the adjustment of the motor applied voltage is generally performed by PWM (pulse width). Modulation) is performed by adjusting the duty of the control, and as a motor, a brushless motor that is excellent in durability and maintainability, and has less noise and noise is generally used.
  • the general configuration of the electric power steering apparatus will be described with reference to FIG.
  • the tie rods 6a and 6b are connected to the steered wheels 8L and 8R via the hub units 7a and 7b.
  • the column shaft 2 is provided with a torque sensor 10 for detecting the steering torque of the handle 1 and a steering angle sensor 14 for detecting the steering angle ⁇ , and the motor 20 for assisting the steering force of the handle 1 is provided with the reduction gear 3.
  • the control unit (ECU) 30 that controls the electric power steering apparatus is supplied with electric power from the battery 13 and also receives an ignition key signal via the ignition key 11.
  • the control unit 30 calculates a current command value of an assist (steering assistance) command based on the steering torque Th detected by the torque sensor 10 and the vehicle speed Vel detected by the vehicle speed sensor 12, and compensates the current command value.
  • the current supplied to the EPS motor 20 is controlled by the voltage control command value Vref subjected to.
  • the steering angle sensor 14 is not essential and may not be provided, and the steering angle can be acquired from a rotational position sensor such as a resolver connected to the motor 20.
  • the control unit 30 is connected to a CAN (Controller Area Network) 40 that transmits and receives various types of vehicle information, and the vehicle speed Vel can also be received from the CAN 40.
  • the control unit 30 can be connected to a non-CAN 41 that exchanges communications, analog / digital signals, radio waves, and the like other than the CAN 40.
  • FIG. 1 An example of a power transmission mechanism of the motor 20 of the electric power steering apparatus and an example of connection between the motor 20 and the control unit (ECU) 30 are as shown in FIG.
  • the output shaft 201 of the motor 20 extends to the outside of the motor housing 202, and the motor housing 202 forming the motor yoke has a substantially bottomed cylinder that accommodates a motor body having a rotor and the like.
  • the case main body 203 and a motor attachment portion 204 attached to the opening side of the case main body 203 are configured.
  • the motor mounting portion 204 is formed in a plate shape as a whole, and the output shaft 201 is inserted through the outside of the motor mounting portion 204 through a through hole in the center.
  • the motor mounting portion 204 may be formed in a flange shape.
  • the power transmission mechanism 60 connected to the motor 20 includes a worm reduction mechanism including a worm 61 and a worm wheel 62, and includes a connecting portion 63 that connects the worm reduction mechanism and the output shaft 201.
  • the worm 61 is formed at an intermediate portion of a worm shaft 61 ⁇ / b> A coaxial with the output shaft 201 and meshes with the worm wheel 62.
  • An upper (handle) side output shaft 2 ⁇ / b> A of the column shaft 2 that rotates integrally with the worm wheel 62 is connected to the shaft center of the worm wheel 62.
  • the rotation of the motor 20, that is, the rotation of the output shaft 201 is decelerated by the worm deceleration mechanism and transmitted to the upper output shaft 2A.
  • the internal space of the motor mounting portion 64 on the speed reduction mechanism side is formed in a trumpet shape so as to expand toward the motor 20 side (opening side), and the motor mounting portion 64 is connected to the motor mounting portion 24 on the motor 20 side. By bolting, the opening of the motor attachment portion 64 is closed.
  • the connecting portion 63 and the output shaft 201 are positioned at the axial center of the internal space of the motor attachment portion 64.
  • the motor mounting portion 64 is formed in a flange shape
  • the motor mounting portion 64 is also formed in a flange shape correspondingly.
  • the motor 20 and the control unit (ECU) 30 or the ECU board are separated from each other and wired by a lead wire 31, and the motor 20 is driven and controlled by the control unit (ECU) 30 via the lead wire 31.
  • Patent Document 1 As a method of connecting a rotational position sensor to a motor, for example, there is one disclosed in Japanese Patent No. 3786667 (Patent Document 1). This is configured for the purpose of improving the accuracy of phase alignment and improving the stability after fixing by fixing the resolver by screw fastening. Regarding the phase positioning of the resolver, after the phase adjustment by excitation, the resolver is screwed and fixed to the bracket, which is an assembly method suitable for mass production.
  • the stator coil is also provided with adjusting means for adjusting the position of the signal rotor or the detection stator by energizing the stator coil and rotating and restricting the rotor by a predetermined angle or more.
  • the present invention has been made under the circumstances as described above, and an object of the present invention is to provide a concave portion on the bottom surface of the yoke so that the rotational position sensor can be easily fastened to the motor with a simple method and with a coaxiality. It is an object of the present invention to provide a motor having a structure, and an electric power steering device and a vehicle equipped with the motor.
  • the present invention relates to a motor in which all or part of the outer periphery and one bottom surface are covered with a case made of a pressed steel plate.
  • the above object of the present invention is to provide a recess for inserting a rotational position sensor on the bottom surface of the case. This is achieved by the structure in which the wall surface of the recess is used for introducing the rotational position sensor.
  • the object of the present invention is that the rotational position sensor is a resolver stator, or that a beat is provided in the insulator resin portion of the resolver stator so that the coaxiality can be obtained by light press-fitting, or This is more effectively achieved by screwing the resolver stator and the other bottom surface of the yoke.
  • An electric power steering apparatus that applies driving force to the vehicle steering system and a vehicle equipped with the electric power steering apparatus are achieved by a current command value that is driven and controlled by the brushless motor and is calculated based on at least the steering torque.
  • a recess is formed on the bottom surface of the yoke (case) of the motor so that a rotational position sensor such as a resolver or MR sensor can be inserted from the outside, and the wall surface of the concave can be used for inserting the rotational position sensor.
  • a rotational position sensor such as a resolver or MR sensor
  • the rotational position sensor can be easily fastened and the coaxiality can be easily adjusted.
  • the rotational position sensor is a resolver, there is an advantage that it is easier to introduce by providing a beat in the insulator resin portion.
  • a hole is made in the bottom surface of the motor yoke, and the rotational position sensor can be fixed by screw fastening, so that phase alignment becomes easy.
  • the space for the rotational position sensor can be placed inside the motor, so that space saving in the axial direction of the motor can also be achieved.
  • the motor structure of the present invention can secure a mounting space for a rotational position sensor such as a resolver and provide positioning of the rotational position sensor by providing a circular recess in the bottom surface of the yoke on the opposite side of the load (case made of pressed steel plate).
  • the vertical yoke wall surface facilitates insertion when the rotational position sensor is mounted.
  • the yoke wall surface and the taper surface play a role of smooth sensor introduction when the rotational position sensor is inserted.
  • the rotational position sensor is a resolver, by providing a beat in the insulator resin portion of the resolver stator, it can be inserted into the recess 22 by light press-fitting while having a certain gap.
  • the rotational position sensor is installed on the yoke side, the motor stator and the rotational position sensor are directly coupled to each other, so that it is easy to ensure the coaxiality.
  • a plurality of elongated holes having a margin in the circumferential direction are formed on the bottom surface of the yoke, and the resolver stator can be screwed and fixed to the yoke while adjusting the motor phase.
  • the resolver stator on the yoke bottom surface (a structure in which the motor is not blocked by another member such as a housing and the yoke covering the circumferential direction covers the bottom surface as it is).
  • the resolver installation direction does not depend on the load side or the anti-load side of the motor.
  • FIG. 3 is an assembly diagram of a structural example of the motor 20 and the resolver stator 50 according to the present invention
  • FIG. 4 is a sectional sectional view of the recess of the motor 20 according to the present invention
  • 5 is a cross-sectional view showing a state where the resolver stator 50 is mounted on the motor 20 according to the present invention
  • FIG. 6 is a perspective view.
  • the outer periphery of the motor 20 is covered by a yoke 21, and a concave portion 22 that is recessed in a circular shape for receiving the resolver stator 50 is formed on one bottom surface on the side opposite to the load of the yoke 21.
  • a vertical wall surface 22A is formed on the inner periphery.
  • the load side of the yoke 21 is completely or partially blocked and the output shaft protrudes.
  • the diameter of the recess 22 is adjusted to match the outer diameter of the resolver stator 50 in order to position the resolver stator 50 and the bearing 23 in the direction of the motor shaft 25.
  • the protrusion 22B is formed in the center part.
  • the resolver space exists inside the motor 20, and is responsible for space saving in the axial direction of the motor 20.
  • the concave portion 22 of the yoke 21 there is a vertical wall surface 22A for introducing the resolver stator 50, which simultaneously provides the coaxiality of the resolver stator 50.
  • the resolver stator 50 by providing a convex beat by ribing along the outer surface axial direction of the insulator resin 51 of the resolver stator 50, it has a certain degree of coaxiality accuracy while having a margin for phase adjustment by light press-fitting. Can be inserted.
  • a rounded taper is provided on the inner side of the upper end of the recess 22 so that the resolver stator 50 can be inserted into the recess 22 more easily and smoothly.
  • the mounting portion 53 on the flat plate of the resolver stator 50 is fastened and fixed with screws 52 or the like.
  • a plurality of elongated holes 26 are formed in the yoke 21 along the circumferential direction, and are screwed into the holes 26.
  • bus bars 70 of two systems (two systems each of U, V, and W phases) of the motor 20 protrude from the six holes 26.
  • the recess 22 Since the resolver stator 50 is inserted and fixed in the recess 22, the recess 22 has a dimensional volume capable of receiving the resolver stator 50. Accordingly, the dimensional relationship between the recess 22 and the resolver stator 50 is such that the inner diameter L2 of the recess 22 is L2> L1 with respect to the outer diameter L1 of the resolver stator 50 as shown in FIG. Further, the depth H2 of the concave portion 22 up to the protrusion 22B has a relationship of H2 ⁇ H1 with respect to the height H1 up to the lower surface of the mounting portion 53 of the resolver stator 50.
  • a plurality of elongated holes 26 are provided in the circumferential direction of the yoke 21, and a bus bar 70 protrudes from the holes 26.
  • the hole 2 can also be used as a hole for fixing the resolver stator 50, and the motor or bus bar insulating resin and the resolver stator 50 are fastened and fixed by screws 52. Since the hole 26 has a long shape, the phase can be adjusted when the resolver stator 50 is fastened and fixed.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Steering Mechanism (AREA)
  • Brushless Motors (AREA)

Abstract

[Problem] To provide a motor having a structure in which a recess portion is provided on a bottom of a yoke and fastening a rotational position sensor to the motor can be facilitated by a simple method and with maintaining the coaxiality, and also to provide an electric power steering device and a vehicle mounted with the motor. [Solution] A motor is covered with a case formed of a pressed steel plate on the outer periphery and the entire or a part of one of the bottoms and has such a structure that a recess portion for inserting a rotational position sensor is provided at a bottom of the case and the wall surface of the recess portion is used for introducing the rotational position sensor.

Description

モータ並びにそれを搭載した電動パワーステアリング装置及び車両Motor, electric power steering apparatus equipped with the motor, and vehicle
　本発明は、モータのヨーク（ケース）底面に、レゾルバ等の回転位置センサを外部から挿入できるような凹部を作成し、凹部壁面を回転位置センサの導入に利用できる構造のモータ並びにそれを搭載した電動パワーステアリング装置及び車両に関する。車両に搭載される電動パワーステアリング装置は、少なくとも操舵トルクに基づいて演算された電流指令値により、車両の操舵系にモータ（例えばブラシレスモータ）によるアシスト力を付与するものであり、ブリッジ回路で成るインバータによって駆動制御される。 According to the present invention, a recess is formed on the bottom of a motor yoke (case) so that a rotational position sensor such as a resolver can be inserted from the outside, and a motor having a structure in which the concave wall surface can be used for introduction of the rotational position sensor and the motor mounted thereon The present invention relates to an electric power steering apparatus and a vehicle. An electric power steering device mounted on a vehicle applies an assist force by a motor (for example, a brushless motor) to a steering system of the vehicle based on a current command value calculated based on at least a steering torque, and includes a bridge circuit. Drive controlled by an inverter.
　駆動部にモータを搭載した装置として電動パワーステアリング装置（ＥＰＳ）があり、電動パワーステアリング装置は、車両のステアリング機構にモータの回転力で操舵補助力（アシスト力）を付与するものであり、インバータから供給される電力で制御されるモータの駆動力を、ギア等の伝達機構により、ステアリングシャフト或いはラック軸に操舵補助力を付与する。かかる従来の電動パワーステアリング装置は、操舵補助力のトルクを正確に発生させるため、モータ電流のフィードバック制御を行っている。フィードバック制御は、操舵補助指令値（電流指令値）とモータ電流検出値との差が小さくなるようにモータ印加電圧を調整するものであり、モータ印加電圧の調整は、一般的にＰＷＭ（パルス幅変調）制御のデューティの調整で行っており、モータとしては耐久性や保守性に優れ、騒音やノイズも少ないブラシレスモータが一般的に使用されている。 There is an electric power steering device (EPS) as a device in which a motor is mounted on the drive unit, and the electric power steering device applies a steering assist force (assist force) to the steering mechanism of the vehicle by the rotational force of the motor. The driving force of the motor controlled by the electric power supplied from the motor is applied to the steering shaft or the rack shaft by a transmission mechanism such as a gear. Such a conventional electric power steering apparatus performs feedback control of the motor current in order to accurately generate the torque of the steering assist force. In feedback control, the motor applied voltage is adjusted so that the difference between the steering assist command value (current command value) and the motor current detection value is small. The adjustment of the motor applied voltage is generally performed by PWM (pulse width). Modulation) is performed by adjusting the duty of the control, and as a motor, a brushless motor that is excellent in durability and maintainability, and has less noise and noise is generally used.
　電動パワーステアリング装置の一般的な構成を図１に示して説明すると、ハンドル１のコラム軸（ステアリングシャフト、ハンドル軸）２は減速部内の減速ギア３、ユニバーサルジョイント４ａ及び４ｂ、ピニオンラック機構５、タイロッド６ａ，６ｂを経て、更にハブユニット７ａ，７ｂを介して操向車輪８Ｌ，８Ｒに連結されている。また、コラム軸２には、ハンドル１の操舵トルクを検出するトルクセンサ１０及び操舵角θを検出する舵角センサ１４が設けられており、ハンドル１の操舵力を補助するモータ２０が減速ギア３を介してコラム軸２に連結されている。電動パワーステアリング装置を制御するコントロールユニット（ＥＣＵ）３０には、バッテリ１３から電力が供給されると共に、イグニションキー１１を経てイグニションキー信号が入力される。コントロールユニット３０は、トルクセンサ１０で検出された操舵トルクＴｈと車速センサ１２で検出された車速Ｖｅｌとに基づいてアシスト（操舵補助）指令の電流指令値の演算を行い、電流指令値に補償等を施した電圧制御指令値Ｖｒｅｆによって、ＥＰＳ用モータ２０に供給する電流を制御する。 The general configuration of the electric power steering apparatus will be described with reference to FIG. The tie rods 6a and 6b are connected to the steered wheels 8L and 8R via the hub units 7a and 7b. Further, the column shaft 2 is provided with a torque sensor 10 for detecting the steering torque of the handle 1 and a steering angle sensor 14 for detecting the steering angle θ, and the motor 20 for assisting the steering force of the handle 1 is provided with the reduction gear 3. Are connected to the column shaft 2 via The control unit (ECU) 30 that controls the electric power steering apparatus is supplied with electric power from the battery 13 and also receives an ignition key signal via the ignition key 11. The control unit 30 calculates a current command value of an assist (steering assistance) command based on the steering torque Th detected by the torque sensor 10 and the vehicle speed Vel detected by the vehicle speed sensor 12, and compensates the current command value. The current supplied to the EPS motor 20 is controlled by the voltage control command value Vref subjected to.
　なお、舵角センサ１４は必須のものではなく、配設されていなくても良く、また、モータ２０に連結されたレゾルバ等の回転位置センサから操舵角を取得することも可能である。 It should be noted that the steering angle sensor 14 is not essential and may not be provided, and the steering angle can be acquired from a rotational position sensor such as a resolver connected to the motor 20.
　コントロールユニット３０には、車両の各種情報を授受するＣＡＮ（Controller Area Network）４０が接続されており、車速ＶｅｌはＣＡＮ４０から受信することも可能である。また、コントロールユニット３０には、ＣＡＮ４０以外の通信、アナログ／ディジタル信号、電波等を授受する非ＣＡＮ４１も接続可能である。 The control unit 30 is connected to a CAN (Controller Area Network) 40 that transmits and receives various types of vehicle information, and the vehicle speed Vel can also be received from the CAN 40. The control unit 30 can be connected to a non-CAN 41 that exchanges communications, analog / digital signals, radio waves, and the like other than the CAN 40.
　電動パワーステアリング装置のモータ２０の動力伝達機構例、及びモータ２０及びコントロールユニット（ＥＣＵ）３０の接続例は図２に示すようになっている。 An example of a power transmission mechanism of the motor 20 of the electric power steering apparatus and an example of connection between the motor 20 and the control unit (ECU) 30 are as shown in FIG.
　図２に示すように、モータ２０の出力軸２０１はモータハウジング２０２の外側に延在しており、モータヨークを形成するモータハウジング２０２は、ロータ等を備えたモータ本体を収容する有底略円筒状のケース本体２０３と、ケース本体２０３の開口側に取付けられたモータ取付け部２０４とで構成されている。モータ取付け部２０４は全体として板状に形成され、その中央部の貫通孔を介して出力軸２０１をモータ取付け部２０４の外側に挿通させている。なお、モータ取付け部２０４をフランジ状に形成してもよい。 As shown in FIG. 2, the output shaft 201 of the motor 20 extends to the outside of the motor housing 202, and the motor housing 202 forming the motor yoke has a substantially bottomed cylinder that accommodates a motor body having a rotor and the like. The case main body 203 and a motor attachment portion 204 attached to the opening side of the case main body 203 are configured. The motor mounting portion 204 is formed in a plate shape as a whole, and the output shaft 201 is inserted through the outside of the motor mounting portion 204 through a through hole in the center. The motor mounting portion 204 may be formed in a flange shape.
　モータ２０に連結された動力伝達機構６０は、ウォーム６１及びウォームホイール６２から成るウォーム減速機構を有し、ウォーム減速機構と出力軸２０１とを連結する連結部６３を備えている。ウォーム６１は、出力軸２０１と同軸のウォームシャフト６１Ａの中間部に形成され、ウォームホイール６２に噛合している。ウォームホイール６２の軸心には、ウォームホイール６２と一体回転するコラム軸２のアッパー（ハンドル）側出力軸２Ａが連結されている。ウォーム減速機構によって、モータ２０の回転、即ち出力軸２０１の回転が減速されてアッパー側出力軸２Ａに伝達される。 The power transmission mechanism 60 connected to the motor 20 includes a worm reduction mechanism including a worm 61 and a worm wheel 62, and includes a connecting portion 63 that connects the worm reduction mechanism and the output shaft 201. The worm 61 is formed at an intermediate portion of a worm shaft 61 </ b> A coaxial with the output shaft 201 and meshes with the worm wheel 62. An upper (handle) side output shaft 2 </ b> A of the column shaft 2 that rotates integrally with the worm wheel 62 is connected to the shaft center of the worm wheel 62. The rotation of the motor 20, that is, the rotation of the output shaft 201 is decelerated by the worm deceleration mechanism and transmitted to the upper output shaft 2A.
　減速機構側のモータ取付け部６４の内部空間は、モータ２０側（開口側）に向かって拡開するようにラッパ形状に形成されており、モータ取付け部６４がモータ２０側のモータ取付け部２４にボルト止めされることで、モータ取付け部６４の開口が閉塞される。モータ取付け部６４にモータ２０を取付けた図２に示す状態では、モータ取付け部６４の内部空間の軸心に連結部６３及び出力軸２０１が位置するようになっている。なお、モータ取付け部６４をフランジ状に形成した場合には、これに対応して、モータ取付け部６４もフランジ状に形成する。 The internal space of the motor mounting portion 64 on the speed reduction mechanism side is formed in a trumpet shape so as to expand toward the motor 20 side (opening side), and the motor mounting portion 64 is connected to the motor mounting portion 24 on the motor 20 side. By bolting, the opening of the motor attachment portion 64 is closed. In the state shown in FIG. 2 in which the motor 20 is attached to the motor attachment portion 64, the connecting portion 63 and the output shaft 201 are positioned at the axial center of the internal space of the motor attachment portion 64. When the motor mounting portion 64 is formed in a flange shape, the motor mounting portion 64 is also formed in a flange shape correspondingly.
　また、モータ２０とコントロールユニット（ＥＣＵ）３０若しくはＥＣＵ基板とは離間してリード線３１で配線されており、モータ２０はコントロールユニット（ＥＣＵ）３０によってリード線３１を介して駆動制御される。 Further, the motor 20 and the control unit (ECU) 30 or the ECU board are separated from each other and wired by a lead wire 31, and the motor 20 is driven and controlled by the control unit (ECU) 30 via the lead wire 31.
　このような電動パワーステアリング装置において、モータとしてブラシレスモータを使用した場合には、モータ回転位置に応じてモータに供給する電流の通電、遮断を制御する必要があるため、モータ回転位置を検出する必要がある。そのため、モータにレゾルバ、ＭＲセンサ等の回転位置センサが連結される。 In such an electric power steering device, when a brushless motor is used as the motor, it is necessary to control the energization and interruption of the current supplied to the motor in accordance with the motor rotation position, and therefore it is necessary to detect the motor rotation position. There is. Therefore, a rotational position sensor such as a resolver or MR sensor is connected to the motor.
　モータに回転位置センサを連結する手法として、例えば特許第３７８３６６７号公報（特許文献１）に示されるものがある。これは、レゾルバをネジ締結により固定することで、位相合わせの精度向上と、固定後の安定性の向上とを目的として構成されている。レゾルバの位相位置決めについては、励磁による位相調整後、レゾルバをブラケットにネジ止め固定することで、量産に適した組立方法としている。また、固定子コイルに通電して、回転子を予め設定した所定角度以上回転させて拘束し、信号ロータ又は検出ステータの位置を調整する調整手段を備えたものである。 As a method of connecting a rotational position sensor to a motor, for example, there is one disclosed in Japanese Patent No. 3786667 (Patent Document 1). This is configured for the purpose of improving the accuracy of phase alignment and improving the stability after fixing by fixing the resolver by screw fastening. Regarding the phase positioning of the resolver, after the phase adjustment by excitation, the resolver is screwed and fixed to the bracket, which is an assembly method suitable for mass production. The stator coil is also provided with adjusting means for adjusting the position of the signal rotor or the detection stator by energizing the stator coil and rotating and restricting the rotor by a predetermined angle or more.
特許第３７８３６６７号公報Japanese Patent No. 3783667
　しかし、特許文献１に開示された構造では、モータにレゾルバステータを挿入する際のモータ軸との同軸度については全く考慮されていないので、高い同軸度が必要となる場合には使用できない問題がある。従来のモータは、この特許文献１記載のように、ハウジング側にレゾルバステータが設置されているため、ハウジングとヨークとの同軸度、更にハウジングとレゾルバステータとの同軸度を調整する必要があり、その積み重ねを考慮するため、各々の同軸度も厳しく設定する必要があった。 However, in the structure disclosed in Patent Document 1, since the coaxiality with the motor shaft when the resolver stator is inserted into the motor is not considered at all, there is a problem that it cannot be used when high coaxiality is required. is there. Since the conventional motor has a resolver stator installed on the housing side as described in Patent Document 1, it is necessary to adjust the coaxiality between the housing and the yoke, and the coaxiality between the housing and the resolver stator. In order to consider the accumulation, it was necessary to set each coaxiality strictly.
　本発明は上述のような事情よりなされたものであり、本発明の目的は、ヨークの底面に凹部を設け、回転位置センサのモータへの締結を簡易な手法でかつ同軸度をもって容易に行い得る構造のモータ並びにそれを搭載した電動パワーステアリング装置及び車両を提供することにある。 The present invention has been made under the circumstances as described above, and an object of the present invention is to provide a concave portion on the bottom surface of the yoke so that the rotational position sensor can be easily fastened to the motor with a simple method and with a coaxiality. It is an object of the present invention to provide a motor having a structure, and an electric power steering device and a vehicle equipped with the motor.
　本発明は、外周及び一方の底面の全部又は一部がプレス鋼板によるケースで包括されているモータに関し、本発明の上記目的は、前記ケースの底面に回転位置センサを挿入するための凹部が設けられ、前記凹部の壁面を前記回転位置センサの導入に利用する構造となっていることにより達成される。 The present invention relates to a motor in which all or part of the outer periphery and one bottom surface are covered with a case made of a pressed steel plate. The above object of the present invention is to provide a recess for inserting a rotational position sensor on the bottom surface of the case. This is achieved by the structure in which the wall surface of the recess is used for introducing the rotational position sensor.
　本発明の上記目的は、前記回転位置センサがレゾルバステータであることにより、或いは前記レゾルバステータのインシュレータ樹脂部にビートが設けられ、軽圧入で同軸度を出せる構造となっていることにより、或いは前記レゾルバステータと前記ヨークの他方の底面とがネジ締結されていることにより、より効果的に達成される。 The object of the present invention is that the rotational position sensor is a resolver stator, or that a beat is provided in the insulator resin portion of the resolver stator so that the coaxiality can be obtained by light press-fitting, or This is more effectively achieved by screwing the resolver stator and the other bottom surface of the yoke.
　上記ブラシレスモータで駆動制御され、少なくとも操舵トルクに基づいて演算された電流指令値により、車両の操舵系にアシスト力を付与する電動パワーステアリング装置及びそれを搭載した車両が達成される。 An electric power steering apparatus that applies driving force to the vehicle steering system and a vehicle equipped with the electric power steering apparatus are achieved by a current command value that is driven and controlled by the brushless motor and is calculated based on at least the steering torque.
　本発明のモータによれば、モータのヨーク（ケース）底面に、レゾルバ、ＭＲセンサ等の回転位置センサが外部から挿入できるような凹部を形成し、凹部の壁面を回転位置センサの挿入に利用できるようにしているので、回転位置センサの締結が容易であり、同軸度の調整も容易である。回転位置センサがレゾルバの場合、インシュレータ樹脂部にビートを設けることで、一層導入し易くなる利点がある。 According to the motor of the present invention, a recess is formed on the bottom surface of the yoke (case) of the motor so that a rotational position sensor such as a resolver or MR sensor can be inserted from the outside, and the wall surface of the concave can be used for inserting the rotational position sensor. Thus, the rotational position sensor can be easily fastened and the coaxiality can be easily adjusted. When the rotational position sensor is a resolver, there is an advantage that it is easier to introduce by providing a beat in the insulator resin portion.
　また、モータヨークの底面に穴が開けられており、回転位置センサをネジ締結により固定できるので、位相合わせが容易となる。モータヨークに凹部を作成することで、回転位置センサのスペースをモータ内部に置くことができるため、モータの軸方向の省スペース化を図ることもできる。 Also, a hole is made in the bottom surface of the motor yoke, and the rotational position sensor can be fixed by screw fastening, so that phase alignment becomes easy. By creating a recess in the motor yoke, the space for the rotational position sensor can be placed inside the motor, so that space saving in the axial direction of the motor can also be achieved.
　上記構造のモータを電動パワーステアリング装置に適用することにより、位置決め精度が高く、安価で信頼性の高い電動パワーステアリング装置を達成でき、かかる電動パワーステアリング装置を車両に搭載することにより、車両の一層の安定化、コストダウンを図ることがきる。 By applying the motor having the above structure to an electric power steering device, an electric power steering device with high positioning accuracy, low cost and high reliability can be achieved. Stabilization and cost reduction.
電動パワーステアリング装置の概要を示す構成図である。It is a lineblock diagram showing an outline of an electric power steering device. 電動パワーステアリング装置のモータと減速部の連結機構例及びコントロールユニット（ＥＣＵ）との接続例を示す図である。It is a figure which shows the connection example of the connection mechanism example of the motor of the electric power steering device, the connection part of a deceleration part, and a control unit (ECU). 本発明に係るモータの構造例及びレゾルバステータの組立図である。It is an assembly drawing of a structural example of a motor and a resolver stator according to the present invention. 本発明に係るモータの凹部断面機構図である。It is a recessed part cross-section mechanism figure of the motor which concerns on this invention. 本発明に係るモータにレゾルバステータを装着した状態を示す断面図である。It is sectional drawing which shows the state which mounted | wore the motor which concerns on this invention with the resolver stator. 本発明に係るモータにレゾルバステータを装着した状態を示す斜視図である。It is a perspective view which shows the state which mounted | wore the motor which concerns on this invention with the resolver stator.
　本発明のモータ構造は、反負荷側のヨーク底面（プレス鋼板によるケース）に円形状に窪んだ凹部を設けることにより、レゾルバ等の回転位置センサの装着スペースを確保できると共に、回転位置センサの位置決めを容易に行うことができ、垂直なヨーク壁面により回転位置センサ装着時の挿入を円滑にできる。このヨーク壁面及びテーパ面が、回転位置センサ挿入時に滑らかなセンサ導入の役割を担う。また、回転位置センサがレゾルバの場合、レゾルバステータのインシュレータ樹脂部にビートを設けることで、ある程度の隙間を持ちつつ、軽圧入にて凹部２２に挿入することができる。ヨーク側に回転位置センサが設置されることで、モータステータと回転位置センサとが直接結合されるため、同軸度の確保が容易となる。また、ヨーク底面に、円周方向に余裕をもつ長形状の穴が複数開けられており、モータ位相を調整しつつ、レゾルバステータをヨークにネジ締結し固定することができる。 The motor structure of the present invention can secure a mounting space for a rotational position sensor such as a resolver and provide positioning of the rotational position sensor by providing a circular recess in the bottom surface of the yoke on the opposite side of the load (case made of pressed steel plate). The vertical yoke wall surface facilitates insertion when the rotational position sensor is mounted. The yoke wall surface and the taper surface play a role of smooth sensor introduction when the rotational position sensor is inserted. Further, when the rotational position sensor is a resolver, by providing a beat in the insulator resin portion of the resolver stator, it can be inserted into the recess 22 by light press-fitting while having a certain gap. Since the rotational position sensor is installed on the yoke side, the motor stator and the rotational position sensor are directly coupled to each other, so that it is easy to ensure the coaxiality. In addition, a plurality of elongated holes having a margin in the circumferential direction are formed on the bottom surface of the yoke, and the resolver stator can be screwed and fixed to the yoke while adjusting the motor phase.
　また、本発明のモータ構造は、ヨーク底面(ハウジング等別部材でモータを塞がず、円周方向をカバーしているヨークがそのまま底面まで覆っている構造)にレゾルバステータを設置する必要はあるが、ヨークの向きによっては、レゾルバの設置方向はモータの負荷側・反負荷側には拠らない。 Further, in the motor structure of the present invention, it is necessary to install the resolver stator on the yoke bottom surface (a structure in which the motor is not blocked by another member such as a housing and the yoke covering the circumferential direction covers the bottom surface as it is). However, depending on the direction of the yoke, the resolver installation direction does not depend on the load side or the anti-load side of the motor.
　以下に、本発明の実施形態を図面を参照して説明する。 Embodiments of the present invention will be described below with reference to the drawings.
　図３は、本発明に係るモータ２０の構造例及びレゾルバステータ５０の組立図であり、図４は、本発明に係るモータ２０の凹部断面機構図である。また、図５は、本発明に係るモータ２０にレゾルバステータ５０を装着した状態を示す断面図であり、図６は斜視図である。 3 is an assembly diagram of a structural example of the motor 20 and the resolver stator 50 according to the present invention, and FIG. 4 is a sectional sectional view of the recess of the motor 20 according to the present invention. 5 is a cross-sectional view showing a state where the resolver stator 50 is mounted on the motor 20 according to the present invention, and FIG. 6 is a perspective view.
　モータ２０の外周はヨーク２１で包括されており、ヨーク２１の反負荷側である一方の底面に、レゾルバステータ５０を受容する円形状に窪んだ凹部２２が形成されており、凹部２２の外側の内周には垂直な壁面２２Ａが形成されている。ヨーク２１の負荷側は、図示はしないが全部又は一部が塞がれて出力軸が突出している。また、凹部２２の中央部に軸受２３を中に介在させているため、レゾルバステータ５０と軸受２３とをモータ軸２５方向に位置決めすべく、レゾルバステータ５０の外径に合わせて、凹部２２の直径（内径）を変化させるように弾性部材で形成すると共に、中央部に隆起２２Ｂを形成している。底面のヨーク２１に凹部２２を形成することで、レゾルバのスペースはモータ２０の内部に存在することになり、モータ２０の軸方向の省スペース化を担っている。 The outer periphery of the motor 20 is covered by a yoke 21, and a concave portion 22 that is recessed in a circular shape for receiving the resolver stator 50 is formed on one bottom surface on the side opposite to the load of the yoke 21. A vertical wall surface 22A is formed on the inner periphery. Although not shown, the load side of the yoke 21 is completely or partially blocked and the output shaft protrudes. Further, since the bearing 23 is interposed in the central portion of the recess 22, the diameter of the recess 22 is adjusted to match the outer diameter of the resolver stator 50 in order to position the resolver stator 50 and the bearing 23 in the direction of the motor shaft 25. While forming with an elastic member so that (inner diameter) may be changed, the protrusion 22B is formed in the center part. By forming the concave portion 22 in the yoke 21 on the bottom surface, the resolver space exists inside the motor 20, and is responsible for space saving in the axial direction of the motor 20.
　ヨーク２１の凹部２２にはレゾルバステータ５０を導入するための垂直な壁面２２Ａが存在し、これが同時にレゾルバステータ５０の同軸度を出している。また、レゾルバステータ５０のインシュレータ樹脂５１の外面軸方向に沿って、リブ出し加工による凸形状のビートを設けることで、軽圧入にて位相調整の余裕を持ちながら、ある程度の同軸度精度を持って挿入することができる。凹部２２の上面端部内側には丸みを持ったテーパが付けられており、レゾルバステータ５０の凹部２２への挿入を更に容易かつ円滑に行い得るようにしている。 In the concave portion 22 of the yoke 21, there is a vertical wall surface 22A for introducing the resolver stator 50, which simultaneously provides the coaxiality of the resolver stator 50. In addition, by providing a convex beat by ribing along the outer surface axial direction of the insulator resin 51 of the resolver stator 50, it has a certain degree of coaxiality accuracy while having a margin for phase adjustment by light press-fitting. Can be inserted. A rounded taper is provided on the inner side of the upper end of the recess 22 so that the resolver stator 50 can be inserted into the recess 22 more easily and smoothly.
　レゾルバステータ５０を凹部２２に挿入後、レゾルバステータ５０の平板上の取付部５３をネジ５２等で締結して固定する。ヨーク２１には円周方向に沿って複数の長形状の穴２６が開けられており、この穴２６にネジ止めする。また、穴２６の６つには、モータ２０の２系統（Ｕ、Ｖ、Ｗ相の各２系統）のバスバー７０が突出している。 After the resolver stator 50 is inserted into the recess 22, the mounting portion 53 on the flat plate of the resolver stator 50 is fastened and fixed with screws 52 or the like. A plurality of elongated holes 26 are formed in the yoke 21 along the circumferential direction, and are screwed into the holes 26. In addition, bus bars 70 of two systems (two systems each of U, V, and W phases) of the motor 20 protrude from the six holes 26.
　レゾルバステータ５０は凹部２２内に挿入されて固定されるので、凹部２２はレゾルバステータ５０を受容できる寸法容積を備えている。従って、凹部２２とレゾルバステータ５０の寸法関係は、図４に示すように凹部２２の内径Ｌ２はレゾルバステータ５０の外径Ｌ１に対してＬ２＞Ｌ１の関係である。また、凹部２２の隆起２２Ｂまでの深さＨ２は、レゾルバステータ５０の取付部５３の下面までの高さＨ１に対してＨ２≧Ｈ１の関係である。 Since the resolver stator 50 is inserted and fixed in the recess 22, the recess 22 has a dimensional volume capable of receiving the resolver stator 50. Accordingly, the dimensional relationship between the recess 22 and the resolver stator 50 is such that the inner diameter L2 of the recess 22 is L2> L1 with respect to the outer diameter L1 of the resolver stator 50 as shown in FIG. Further, the depth H2 of the concave portion 22 up to the protrusion 22B has a relationship of H2 ≧ H1 with respect to the height H1 up to the lower surface of the mounting portion 53 of the resolver stator 50.
　図６に示すように、ヨーク２１の円周方向に長形状の穴２６が複数個設けられており、穴２６からバスバー７０が突出されている。穴２はレゾルバステータ５０を固定するための穴としても使用でき、ネジ５２によりモータ又はバスバー絶縁樹脂とレゾルバステータ５０とを締結して固定する。穴２６は長形状になっているため、レゾルバステータ５０の締結固定時に位相調整を行うことができる。  As shown in FIG. 6, a plurality of elongated holes 26 are provided in the circumferential direction of the yoke 21, and a bus bar 70 protrudes from the holes 26. The hole 2 can also be used as a hole for fixing the resolver stator 50, and the motor or bus bar insulating resin and the resolver stator 50 are fastened and fixed by screws 52. Since the hole 26 has a long shape, the phase can be adjusted when the resolver stator 50 is fastened and fixed.
１　　　　　　　　　　ハンドル
２　　　　　　　　　　コラム軸（ステアリングシャフト、ハンドル軸）
１０　　　　　　　　　トルクセンサ
１２　　　　　　　　　車速センサ
１４　　　　　　　　　舵角センサ
２０　　　　　　　　　モータ
３０　　　　　　　　　コントロールユニット（ＥＣＵ）
４０　　　　　　　　　ＣＡＮ
５０　　　　　　　　　レゾルバステータ
６０　　　　　　　　　動力伝達機構
７０　　　　　　　　　バスバー 1 Handle 2 Column shaft (steering shaft, handle shaft)
10 Torque sensor 12 Vehicle speed sensor 14 Rudder angle sensor 20 Motor 30 Control unit (ECU)
40 CAN
50 Resolver stator 60 Power transmission mechanism 70 Bus bar

Claims (6)

  1. 外周及び一方の底面の全部又は一部がプレス鋼板によるケースで包括されているモータであり、
    前記ケースの底面に回転位置センサを挿入するための凹部が設けられ、前記凹部の壁面を前記回転位置センサの導入に利用する構造となっているモータ。     A motor in which all or part of the outer periphery and one bottom surface is enclosed by a case made of pressed steel sheet,
    A motor having a structure in which a concave portion for inserting a rotational position sensor is provided on a bottom surface of the case, and a wall surface of the concave portion is used for introducing the rotational position sensor.
  2. 前記回転位置センサがレゾルバステータである請求項１に記載のモータ。 The motor according to claim 1, wherein the rotational position sensor is a resolver stator.
  3. 前記レゾルバステータのインシュレータ樹脂部にビートが設けられ、軽圧入で同軸度を出せる構造となっている請求項２に記載のモータ。 The motor according to claim 2, wherein a beat is provided in an insulator resin portion of the resolver stator so that a coaxial degree can be obtained by light press-fitting.
  4. 前記レゾルバステータと前記ヨークの他方の底面とがネジ締結されている請求項２又は３に記載のモータ。 The motor according to claim 2 or 3, wherein the resolver stator and the other bottom surface of the yoke are screwed together.
  5. 請求項１乃至４のいずれかに記載のモータで駆動制御され、少なくとも操舵トルクに基づいて演算された電流指令値により、車両の操舵系にアシスト力を付与する電動パワーステアリング装置。 An electric power steering device that is driven and controlled by the motor according to any one of claims 1 to 4 and applies an assist force to a steering system of a vehicle based on a current command value calculated based on at least a steering torque.
  6. 請求項５に記載の電動パワーステアリング装置を搭載した車両。 A vehicle equipped with the electric power steering device according to claim 5.
PCT/JP2015/067550 2014-06-19 2015-06-18 Motor, and electric power steering device and vehicle mounted with same WO2015194614A1 (en)

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Citations (8)

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