JP5311103B2 - Vehicle steering system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular steering device which can be downsized in an axial direction while coaxially disposing a steering shaft and an electric motor. <P>SOLUTION: The vehicular steering device 1 has the electric motor 23 for adding steering force to the steering shaft 3. The electric motor 23 has a rotor 30 capable of rotating coaxially and accompanied with the steering shaft 3, a stator 31 including a stator core 34 opposite to the rotor 30 and a coil 35 wound around the stator core 34, a cylindrical motor housing 32 storing the rotor 30 and the stator 31, and a connecting plate 36 connecting the coil 35. The connecting plate 36 is disposed oppositely to an outer surface 68 of an end wall 50 of the motor housing 32. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a vehicle steering apparatus.

Some vehicle steering apparatuses have a steering assist electric motor disposed concentrically with a steering shaft (see, for example, Patent Documents 1, 2, and 3).
Moreover, the coil of the electric motor and the external wiring for power feeding are connected to each other inside the electric motor (for example, see Patent Documents 4 and 5).
JP 2007-331456 A JP 2008-17549 A International Publication No. WO2007 / 024157A1 Specification Japanese Utility Model Publication No. 6-70453 Japanese Patent Laid-Open No. 6-233383

However, since the connection of the coil of the electric motor and the external wiring is made inside the electric motor, the electric motor is increased in size.
Further, when the electric motor of the vehicle steering device is arranged concentrically with the steering shaft, the vehicle steering device tends to increase in size in the axial direction of the steering shaft. As a result, it becomes difficult to mount the vehicle steering device on the vehicle.

  Accordingly, an object of the present invention is to provide a vehicle steering apparatus that can be downsized in the axial direction while coaxially arranging a steering shaft and an electric motor.

The vehicle steering device (1, 1D) of the present invention includes a hollow steering column (25) that surrounds the steering shaft (3) and rotatably supports the steering shaft, and an electric motor (for supplying steering force to the steering shaft ). 23,23D) and provided with, the electric motor, the steering axis coaxial to accompany the rotatable rotor (30), a coil (35) wound on the stator core (34) and the stator core facing the rotor a stator (31) comprising comprises a cylindrical motor housing containing a rotor and a stator (32), connection plate for connecting the coils and (36, 36A), said steering column, detects the steering torque torque tubular portion protruding in the axial direction (S1) is at least partially housed the motor housing end wall (50) of the sensor (20) comprises a (27), the connection to Feature is disposed in the open space surrounding the cylindrical portion at the outside of the torque sensor in the radial direction of the cylindrical portion, the opposite Tei Rukoto the outer surface (68) of the motor housing end wall (50, 51) And

  According to the present invention, since the space for the connection plate is not required inside the motor housing, the motor housing can be reduced in the axial direction. Further, since the connection plate is disposed outside the motor housing, the connection with the connection plate is facilitated. As a result, the space required for connection is reduced as compared with the case where the connection plate faces the inner surface of the end wall. Therefore, the vehicle steering device can be downsized in the axial direction.

  In the present invention, a connection member (38, 39) for connecting the external wiring (37) for supplying electric power to the electric motor and the coil is provided, and the connection member is formed integrally with the wiring board. Terminal (72) may be included. In this case, the terminal of the connection member can be supported by the connection board. Since the connection board is used to support the terminal, the space for supporting the terminal can be reduced. As a result, the vehicle steering device can be further reduced in size.

  In the present invention, the connection plate (36) includes a plurality of metal plates (104), and the terminal includes an extension protrusion (72) extending from each metal plate, The corresponding metal plate may be integrally formed of a single material. In this case, the metal plate and the terminal can be electrically connected to each other. Moreover, since such an electrical connection can be achieved by integrally forming the metal plate and the terminal with a single material, the space for the electrical connection described above can be reduced. As a result, the vehicle steering device can be further reduced in size.

  In the present invention, the connection plate (36) includes a plurality of insulating plates (105), and each of the metal plates includes a flat plate-shaped main body (106). May be stacked alternately. In this case, since the metal plate includes a flat plate-shaped main portion, the structure of the metal plate can be simplified. As a result, the structure of the connection plate can be simplified as compared with a conventional connection plate including a conventional metal plate having a curved plate shape. As a result, the connection board can be reduced in size.

In the present invention, the connection plate (36A) is formed by alternately laminating layers (122, 124, 126, 128) including the conductor (114) and insulating layers (121, 123, 125, 127, 129). Multi-layer circuit board (110) may be included. In this case, since a multilayer circuit board is used for the connection board, the connection board becomes small.
In addition, although the alphanumeric characters in the parentheses indicate reference signs of corresponding components in the embodiments described later, the scope of the claims is not limited by these reference signs.

  A preferred embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic diagram of a schematic configuration of an electric power steering apparatus as a vehicle steering apparatus according to a first embodiment of the present invention. Referring to FIG. 1, an electric power steering system (EPS) 1 includes a steering shaft 3 connected to a steering member 2 such as a steering wheel, and a first universal joint 4 attached to the steering shaft 3. An intermediate shaft 5 connected via a pin, a pinion shaft 7 connected to the intermediate shaft 5 via a second universal joint 6, and a rack tooth 9 meshing with a pinion tooth 8 provided near the end of the pinion shaft 7. And a rack bar 10 as a turning shaft extending in the left-right direction of the automobile.

  The pinion shaft 7 and the rack bar 10 constitute a steering gear 11 composed of a rack and pinion mechanism. The rack bar 10 is supported in a rack housing 13 fixed to the vehicle body 12 so as to be linearly reciprocable via a plurality of bearings (not shown). A pair of tie rods 14 are coupled to the rack bar 10. Each tie rod 14 is connected to a corresponding steered wheel 16 via a corresponding knuckle arm 15.

When the steering member 2 is operated and the steering shaft 3 is rotated, this rotation is converted by the pinion teeth 8 and the rack teeth 9 into a linear motion of the rack bar 10 along the left-right direction of the automobile. Thereby, the turning of the steered wheels 16 is achieved.
The steering shaft 3 is divided into an input shaft 17 connected to the steering member 2 and an output shaft 18 connected to the pinion shaft 7. The input shaft 17 and the output shaft 18 are connected to each other on the same axis via a torsion bar 19. When steering torque is input to the input shaft 17, the torsion bar 19 is elastically torsionally deformed, whereby the input shaft 17 and the output shaft 18 are rotated relative to each other.

  A torque sensor 20 that detects a steering torque based on the amount of relative rotational displacement between the input shaft 17 and the output shaft 18 via the torsion bar 19 is provided. A vehicle speed sensor 21 for detecting the vehicle speed is also provided. An ECU (Electronic Control Unit) 22 is provided as a control device. In addition, an electric motor 23 for generating a steering assist force is provided.

Detection signals from the torque sensor 20 and the vehicle speed sensor 21 are input to the ECU 22. The ECU 22 controls the steering assisting electric motor 23 based on the torque detection result, the vehicle speed detection result, and the like. The output rotation of the electric motor 23 is transmitted to the pinion shaft 7 and converted into a linear motion of the rack bar 10 to assist steering.
The electric power steering apparatus 1 has a steering column 25 that supports the steering shaft 3 to be rotatable. The central axis of the steering shaft 3 is inclined with respect to the front-rear direction (horizontal direction) so that the steering member 2 is on the upper side.

  The steering column 25 includes a column tube 26 that houses a part of the steering shaft 3 and a housing 27 that houses at least a part of the torque sensor 20. An end portion of the column tube 26 and one end portion of the housing 27 are connected to each other. Further, the above-described electric motor 23 for applying a steering force to the steering shaft 3 is connected to the other end of the housing 27.

The electric motor 23 includes a rotatable annular rotor 30, an annular stator 31 that faces the rotor 30 in the radial direction of the rotor 30, and a cylindrical motor housing 32 that houses the rotor 30 and the stator 31. ing. The electric motor 23 is an inner rotor type brushless motor.
The rotor 30 is disposed concentrically with the output shaft 18 of the steering shaft 3. The rotor 30 is fixed to the output shaft 18 so as to be able to rotate along with the output shaft 18.

The inner peripheral surface of the stator 31 faces the outer peripheral surface of the rotor 30 in the radial direction of the rotor 30. Further, the outer peripheral surface of the stator 31 is fixed to the motor housing 32. The stator 31 includes an annular single stator core 34 and a plurality of coils 35 wound around the stator core 34.
The electric motor 23 has a connection plate 36 as a connection member to which a plurality of coils 35 are electrically connected.

The electric power steering apparatus 1 has an external wiring 37 for supplying electric power to the electric motor 23. Further, the electric power steering apparatus 1 has a pair of connectors 38 and 39 as connecting members for connecting the external wiring 37 and the connection plate 36 to each other.
One end of the external wiring 37 is electrically connected to the ECU 22. The other end of the external wiring 37 is electrically connected to one connector 38. The pair of connectors 38 and 39 are electrically connected to each other and can be separated from each other as necessary. The other connector 39 is electrically connected to the connection board 36. The other connector 39 is supported by the connection board 36.

Further, the electric power steering apparatus 1 has a rotational position detection sensor 41 for detecting the rotational angular position of the rotor 30 of the electric motor 23. For example, a resolver or a rotary encoder can be used as the rotational position detection sensor 41.
FIG. 2 is a cross-sectional view of the main part of FIG. 1 and mainly shows the electric motor 23. Referring to FIGS. 1 and 2, the electric power steering apparatus 1 includes first, second, third, fourth, and fifth bearings 43, 44, 45, 46, 47 that support the steering shaft 3. Have.

The first bearing 43 is held at the upper end of the column tube 26 of the steering column 25. The first bearing 43 is a ball bearing as a rolling bearing. The first bearing 43 rotatably supports the upper end portion of the steering shaft 3.
Referring to FIG. 2, the second bearing 44 is held by the housing 27 of the steering column 25. The second bearing 44 is a ball bearing as a rolling bearing. The second bearing 44 rotatably supports the input shaft 17 of the steering shaft 3.

The third bearing 45 is held on the upper portion of the motor housing 32 in the axial direction of the steering shaft 3. The third bearing 45 is a ball bearing as a rolling bearing. The third bearing 45 rotatably supports the upper end portion of the output shaft 18 of the steering shaft 3.
The fourth bearing 46 is held at the lower part of the motor housing 32 in the axial direction of the steering shaft 3. The fourth bearing 46 is a ball bearing as a rolling bearing. A fourth bearing 46 rotatably supports the lower portion of the output shaft 18 of the steering shaft 3.

The fifth bearing 47 is interposed between the input shaft 17 and the output shaft 18. The fifth bearing 47 is held by the output shaft 18 and rotatably supports the input shaft 17. The fifth bearing 47 is a sliding bearing. Note that the fifth bearing 47 may be held by the input shaft 17 and rotatably support the output shaft 18.
In the present embodiment, the electric motor 23 and the steering shaft 3 are arranged concentrically with each other. Further, the electric motor 23 can directly drive the output shaft 18 of the steering shaft 3. That is, the output shaft 18 of the steering shaft 3 and the rotor 30 of the electric motor 23 are fixed to each other so as to be able to rotate together.

  The rotor 30 of the electric motor 23 is rotatably supported by third and fourth bearings 45 and 46 via the steering shaft 3. Thus, the third and fourth bearings 45 and 46 are used both for supporting the rotor 30 and for supporting the output shaft 18. As a result, the number of bearings used in the electric power steering apparatus 1 can be reduced.

The motor housing 32 includes a cylindrical member 49 and a pair of plate-like end walls 50 and 51 that cover both ends of the cylindrical member 49. Corresponding end walls 50 and 51 are attached to both ends of the cylindrical member 49.
Further, one end wall 50 of the motor housing 32 is fixed to the housing 27 of the steering column 25. Specifically, the end wall 50 of the motor housing 32 is formed integrally with the housing 27 of the steering column 25 from a single material.

  In addition, the cylindrical member 49 and any one end wall 50 and 51 may be integrally formed by the single member, and may comprise the single component. Further, the housing 27 of the steering column 25 and the one end wall 50 of the motor housing 32 may be formed as separate parts and fixed to each other. In the following, it is in accordance with the case where the cylindrical member 49 and the pair of end walls 50 and 51 are formed separately from each other, and the one end wall 50 and the housing 27 are integrally formed. I will explain.

The housing 27 has a bearing holding hole 52 that holds the second bearing 44. A second bearing 44 is fitted on the inner periphery of the bearing holding hole 52.
One end wall 50 has a bearing holding hole 53 that holds the third bearing 45. A third bearing 45 is fitted on the inner periphery of the bearing holding hole 53.
The other end wall 51 has a bearing holding hole 54 that holds the fourth bearing 46. A fourth bearing 46 is fitted to the inner periphery of the bearing holding hole 54. These three bearing holding holes 52, 53, 54 are arranged concentrically with each other.

Connection portions 55 and 56 for connecting to the cylindrical member 49 are provided on the outer peripheral edge portions of the end walls 50 and 51.
Both end portions in the axial direction of the cylindrical member 49 have connecting portions 57 and 58 for connecting to the connecting portions 55 and 56 of the corresponding end walls 50 and 51 in a fitted state.
The connecting portion 57 of the cylindrical member 49 and the corresponding connecting portion 55 of the end wall 50 are fixed to each other by a fixing bolt 60. The connecting portion 58 of the cylindrical member 49 and the corresponding connecting portion 56 of the end wall 51 are fixed to each other by a fixing bolt 61.

A rotor 30 and a stator 31 are accommodated in the motor housing 32. The output shaft 18 passes through the motor housing 32. The output shaft 18, the rotor 30, the stator 31, and the motor housing 32 are arranged concentrically with each other.
The rotor 30 includes a cylindrical rotor core 63 and an annular permanent magnet 64 fixed to the outer peripheral surface of the rotor core 63.

The permanent magnet 64 has an annular shape. The permanent magnet 64 has a plurality of magnetic poles that are separated in the circumferential direction of the rotor 30. With respect to the circumferential direction of the rotor 30, magnetic poles of N poles and S poles are formed alternately on the outer peripheral surface of the permanent magnet 64 at a plurality of locations. As the permanent magnet 64, a multipolar ring magnet may be used, or a plurality of segment magnets may be arranged in an annular shape.
The rotor core 63 is coaxially connected to the output shaft 18 via a connecting member 65. The connecting member 65 and the rotor core 63 are connected so as to be able to rotate together and transmit torque. Further, the connecting member 65 and the output shaft 18 are connected so as to be able to rotate together and transmit torque.

The stator 31 has an annular single stator core 34 and a plurality of coils 35. The stator core 34 has an annular single yoke and a plurality of teeth as salient poles that protrude radially inward of the stator 31 from the inner periphery of the yoke.
The outer peripheral surface of the yoke of the stator core 34 forms the outer peripheral surface of the stator 31. Protruding tip portions of the teeth of the stator core 34 form an inner peripheral surface of the stator 31, and are close to the rotor 30 and face each other at a predetermined interval. The plurality of teeth are formed in the same shape as each other, and are equally spaced apart from each other across slots of a predetermined interval in the circumferential direction T of the stator 31. A coil 35 is wound around each tooth.

  The plurality of coils 35 of the stator 31 includes a three-phase coil 35 to which each phase of three-phase alternating current is applied, that is, a U-phase coil 35, a V-phase coil 35, and a W-phase coil 35. It is. Each phase coil 35 includes a plurality of coils 35. Each coil 35 is formed of an electric wire coated with insulation. The U-phase coil 35, the V-phase coil 35, and the W-phase coil 35 are arranged in order in the circumferential direction of the stator 31 so as to repeat this order. In FIG. 3 to be described later, the U-phase coil 35 is denoted by reference numeral 35U, the V-phase coil 35 is denoted by reference numeral 35V, and the W-phase coil 35 is denoted by reference numeral 35W.

Returning to FIG. 2, in this embodiment, both ends of the electric wire of each coil 35 of the electric motor 23 are led out through the insertion holes 67 formed in one end wall 50 of the motor housing 32. Each end portion of each derived electric wire is electrically connected to the connection plate 36.
The connection plate 36 includes one end of a coil 35 of each phase, that is, a U-phase, V-phase, and W-phase coil 35, and an external wiring 37 (feeding line) for power supply corresponding to the above-described three phases. Are electrically connected to each other.

Moreover, the connection board 36 has electrically connected the other edge parts of the electric wire of the coil 35 of each phase. Thus, the three-phase coils 35 are Y-connected (star-connected).
Further, the connection plate 36 is disposed on the outer surface 68 of the end wall 50 of the motor housing 32 so as to face the axial direction S1 of the motor housing 32. The connection plate 36 is disposed close to the outer periphery of the motor housing 32. The connection plate 36 is fixed to the end wall 50 by, for example, a fixing bolt (not shown) with screws.

The connection plate 36 is connected to the ECU 22 via an external wiring 37 and a pair of connectors 38 and 39.
The external wiring 37 has a plurality of (specifically, three) covered electric wires provided for each phase of three-phase alternating current.
One connector 38 has a plurality of, for example, three terminals 70 provided for each three-phase AC phase, and a single connector housing 71. The connector housing 71 holds a plurality of terminals 70 in the accommodated state. The connector housing 71 insulates the terminals 70 from each other. Each terminal 70 is formed of a metal member as a conductor, and a corresponding covered electric wire of the external wiring 37 is electrically connected.

The other connector 39 includes a plurality of, for example, three terminals 72 and a single connector housing 73 that are used for each of the three-phase alternating current phases. The connector housing 73 holds a plurality of terminals 72 in a housed state. The connector housing 73 insulates the terminals 72 from each other. Each terminal 72 is formed of a metal member as a conductor.
The connector housing 71 of one connector 38 and the connector housing 73 of the other connector 39 are connected so as to be separable from each other. In a state where the two connector housings 71 and 73 are connected to each other, the terminals 70 and 72 corresponding to each other of the pair of connectors 38 and 39 are in contact with each other. Thereby, the mutually corresponding terminals 70 and 72 of the pair of connectors 38 and 39 are electrically connected to each other.

  FIG. 3 is a plan view of the connection plate 36 of FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG. FIG. 5 is an exploded view of the connection plate 36 of FIG. Referring to FIGS. 3 and 4, connection plate 36 includes a U-phase first conductor 81, a V-phase second conductor 82, and a W-phase third conductor 83. The fourth conductor 84 for the neutral point and the insulator 85 are provided. The insulator 85 insulates the conductors 81, 82, 83, and 84 described above and covers the conductors 81, 82, 83, and 84. The connection plate 36 has an annular shape.

Referring to FIGS. 3 and 5, the first conductor 81 includes a plurality of second conductors for connecting a single first terminal 87 for feeding power from the external wiring 37 and the U-phase coil 35. Terminal 88 and a connection portion 89 for electrically connecting the first terminal 87 and the second terminal 88 to each other.
The first terminal 87 is electrically connected to a corresponding terminal 72 of the other connector 39 as a connecting member, and is electrically connected to the external wiring 37 via the terminal 72. The second terminal 88 is electrically connected to one end of the electric wire of the U-phase coil 35.

The second conductor 82 includes a single third terminal 91 for supplying power from the external wiring 37, a plurality of fourth terminals 92 for connecting the V-phase coil 35, and the third terminals It has the connection part 93 which electrically connects the terminal 91 and the 4th terminal 92 mutually.
The third terminal 91 is electrically connected to the corresponding terminal 72 of the other connector 39, and is electrically connected to the external wiring 37 via this terminal 72. The fourth terminal 92 is electrically connected to one end of the electric wire of the V-phase coil 35.

The third conductor 83 includes a single fifth terminal 95 for feeding power from the external wiring 37, a plurality of sixth terminals 96 for connecting the W-phase coil 35, and the fifth It has a connection part 97 for electrically connecting the terminal 95 and the sixth terminal 96 to each other.
The fifth terminal 95 is electrically connected to the corresponding terminal 72 of the other connector 39, and is electrically connected to the external wiring 37 via this terminal 72. The sixth terminal 96 is electrically connected to one end of the electric wire of the W-phase coil 35.

The fourth conductor 84 connects the seventh terminal 99 for connecting the U-phase coil 35, the eighth terminal 100 for connecting the V-phase coil 35, and the W-phase coil 35. And a connection portion 102 that electrically connects the seventh terminal 99, the eighth terminal 100, and the ninth terminal 101 to each other.
The seventh terminal 99 is electrically connected to the other end of the electric wire of the U-phase coil 35. The eighth terminal 100 is electrically connected to the other end of the electric wire of the V-phase coil 35. The ninth terminal 101 is electrically connected to the other end of the electric wire of the W-phase coil 35. Accordingly, the other ends of the U-phase, V-phase, and W-phase coils 35 are electrically connected to each other via the fourth conductor 84. The fourth conductor 84 forms a neutral point of the Y connection (star connection).

The first to ninth terminals 87, 88, 91, 92, 95, 96, 99, 100, and 101 are arranged at different positions with respect to the circumferential direction of the connection plate 36.
With reference to FIG. 4 and FIG. 5, in this embodiment, the connection board 36 is comprised by the laminated board. The connection plate 36 includes a plurality of metal plates 104 and a plurality of insulating plates 105.
Each of the first to fourth conductors 81, 82, 83, 84 described above is formed by different metal plates 104. In addition, each of the first to third conductors 81, 82, 83 is composed of a single metal plate 104. The fourth conductor 84 is composed of a plurality of metal plates 104, but may be integrally formed by a single member.

The insulator 85 described above is composed of a plurality of insulating plates 105. Each insulating plate 105 is formed in an annular shape by a synthetic resin member, for example. A concave portion is formed on one surface of the four insulating plates 105. A metal plate 104 is accommodated in the recess. Metal plates 104 and insulating plates 105 are alternately stacked.
For example, the insulating plate 105, the metal plate 104 that forms the second conductor 82, the insulating plate 105, the metal plate 104 that forms the first conductor 81, the insulating plate 105, and the third conductor A metal plate 104 forming 83, an insulating plate 105, a metal plate 104 forming the fourth conductor 84, and the insulating plate 105 are laminated in this order in the axial direction S2 of the connection plate 36.

  Each metal plate 104 has conductivity. Each metal plate 104 includes a flat plate-like main body portion 106 and a plurality of convex portions 107 protruding from the main body portion 106. The main body portion 106 and the plurality of convex portions 107 are integrally formed of a single material. The main body portion 106 extends along the circumferential direction of the connection plate 36 and has an arc shape. Each convex portion 107 protrudes outward in the radial direction of the connection plate 36 from the main body portion 106. The tip of the convex portion 107 protrudes from the insulating plate 105.

Each connection portion 89, 93, 97, 102 of the first to fourth conductors 81, 82, 83, 84 is formed by the main portion 106 of the corresponding metal plate 104. Further, the first to ninth terminals 87, 88, 91, 92, 95, 96, 99, 100, 101 are formed by the convex portions 107 of the metal plate 104.
Further, the connection plate 36 of the present embodiment is formed integrally with the other connector 39. Specifically, the convex portion 107 of the metal plate 104 that forms the power feeding terminals 87, 91, and 95 of the connection plate 36 and the corresponding terminal 72 of the other connector 39 are integrally formed of a single material. ing. The terminal 72 of the other connector 39 is formed of an extended protrusion that extends from the metal plate 104. The extending protrusion is bent from the extending end of the convex portion 107 of the corresponding metal plate 104 and extends in the axial direction S2 of the connection plate 36. Each terminal 72 of the other connector 39 is integrally fixed to the connection plate 36. The connector housing 73 of the other connector 39 is integrally fixed to the connection plate 36.

Thereby, the other connector 39 is supported by the connection board 36. Further, the electrical connection between the terminal 72 of the other connector 39 and the metal plate 104 of the connection plate 36 and the mechanical connection between the terminal 72 of the other connector 39 and the metal plate 104 of the connection plate 36 are collectively performed. Can be achieved.
Each metal plate 104 is made of a press-molded product obtained by punching a metal plate (not shown) as a material. Thereby, the metal plate 104 can be formed at low cost. The manufacturing cost of the metal plate 104 made of a press-formed product is lower than that in the case of using other processing methods such as turning and wire cutting.

  Moreover, since the main body portion 106 of the metal plate 104 has a flat plate shape, the main body portion 106 can be easily formed. For example, a bending process for forming a conventional metal plate can be omitted. In addition, since the main portion 106 of the metal plate 104 and the insulating plate 105 each have a flat plate shape, the metal plate 104 and the insulating plate 105 can be easily stacked on each other. At the same time, the structure of the connection plate 36 is simplified. As a result, the connection board 36 can be reduced in size. Moreover, the manufacturing cost of the connection board 36 can be reduced.

  As described above with reference to FIG. 2, the electric power steering device 1 as the vehicle steering device of the present embodiment includes the electric motor 23 for applying a steering force to the steering shaft 3 as the steering shaft. Yes. The electric motor 23 includes a rotor 30 that can rotate along the same axis as the steering shaft 3, a stator core 34 that faces the rotor 30, a stator 31 that includes a coil 35 wound around the stator core 34, and the rotor 30 and the stator 31. Is provided with a cylindrical motor housing 32 and a connection plate 36 for connecting the coil 35. The connection plate 36 is arranged to face the outer surface 68 of the end wall 50 of the motor housing 32.

  According to this embodiment, since the space of the connection plate 36 is not required inside the motor housing 32, the motor housing 32 can be reduced in size in the axial direction S1. Further, since the connection plate 36 is disposed outside the motor housing 32, the connection with the connection plate 36 is facilitated. As a result, compared with the case where the connection board 36 opposes the inner surface of the end wall 50, the space required for connection is reduced. Therefore, the electric power steering device 1 can be downsized in the axial direction S1.

Moreover, since the connection board 36 is arrange | positioned on the outer side of the motor housing 32, the freedom degree of layout of the connection board 36 becomes high. As a result, compared with the case where the connection board 36 opposes the inner surface of the end wall 50, the space required for connection is reduced.
Referring to FIG. 4, in the present embodiment, the electric power steering apparatus 1 includes a connector 39 as a connecting member for connecting the external wiring 37 for supplying power to the electric motor 23 and the coil 35 to each other. I have. The connector 39 includes a terminal 72 formed integrally with the connection board 36.

In this case, the terminal 72 of the connector 39 can be supported by the connection plate 36. Since the connection plate 36 can be used to support the terminal 72, the space for supporting the terminal 72 can be reduced. As a result, the electric power steering device 1 can be further reduced in size.
In the present embodiment, the connection plate 36 includes a plurality of metal plates 104. The terminal 72 includes an extending protrusion extending from each metal plate 104. Each extending protrusion and the corresponding metal plate 104 are integrally formed of a single material.

In this case, the metal plate 104 and the terminal 72 of the connector 39 can be electrically connected to each other. In addition, since such an electrical connection can be achieved by integrally forming the metal plate 104 and the terminal 72 with a single material, the space for the electrical connection described above can be reduced. As a result, the electric power steering device 1 can be further reduced in size.
In the present embodiment, the connection plate 36 includes a plurality of insulating plates 105. Each metal plate 104 includes a flat plate-shaped main body 106. The main portions 106 of the metal plates 104 and the insulating plates 105 are alternately stacked.

In this case, since the metal plate 104 includes the flat main part 106, the structure of the metal plate 104 can be simplified. As a result, the structure of the connection plate 36 can be simplified as compared with a conventional connection plate including a conventional metal plate having a curved plate shape. As a result, the connection board 36 can be reduced in size.
Moreover, since the electric motor 23 can be reduced in size with respect to the axial direction of the steering shaft 3, the electric power steering device 1 can be easily incorporated into the passenger compartment of the automobile.

Moreover, since the electric motor 23 can be reduced in size, the electric power steering apparatus 1 can be reduced in size. As a result, the electric power steering apparatus 1 can be applied to a smaller automobile.
Since the connection plate 36 and the connectors 38 and 39 are disposed outside the motor housing 32, for example, the connection plate 36 and the connectors 38 and 39 can be applied to a motor housing that cannot accommodate the connection plate 36 therein. Become. Therefore, the connection plate 36 and the connectors 38 and 39 can be shared by more types of electric motors. As a result, the wiring board 36 and the connectors 38 and 39 can be made common in a plurality of types of electric power steering devices using different electric motors.

In addition, since the third and fourth bearings 45 and 46 are also used for supporting the rotor 30 of the electric motor 23 and supporting the steering shaft 3, the number of bearings can be reduced. As a result, the electric power steering device 1 can be made inexpensive.
Moreover, since the number of bearings can be reduced as described above, the bearings can be easily arranged concentrically. As a result, the rotation resistance when rotating the steering shaft 3 can be reduced. Moreover, the dispersion | variation in the above-mentioned rotation resistance for every electric power steering device 1 can be reduced.

Moreover, since the rotor 30 and the steering shaft 3 of the electric motor 23 are disposed concentrically with each other, the electric motor 23 can be prevented from protruding in the radial direction.
Moreover, since the electric motor 23 drives the steering shaft 3 directly, the conventional speed reducer for driving the steering shaft 3 can be eliminated. As a result, for example, noise caused by the reduction gear can be prevented. In addition, the number of parts can be reduced.

Moreover, the following modifications can be considered about this embodiment. In the following description, the difference from the above-described embodiment will be mainly illustrated, and this point will be mainly described. Other configurations are omitted, but are the same as those in the first embodiment described above, and are denoted by the same reference numerals.
For example, FIG. 6 is a plan view of a modified example of the connection plate 36. 7 is a cross-sectional view taken along the line VII-VII in FIG. 6 and 7, the terminal 72 of the other connector 39 extends from the corresponding convex portion 107 of the metal plate 104 in the direction along the plate surface of the main portion 106 of the metal plate 104 of the connection plate 36. Has been. Thereby, since the metal plate 104 and the terminal 72 form flat plate shape, the processing cost of the metal plate 104 and the terminal 72 can be reduced.

Although not shown, in each of the above-described embodiments, the convex portions 107 corresponding to the second, fourth, sixth to ninth terminals 88, 92, 96, 99, 100, 101 of the connection plate 36 are A case where the main body 106 is formed in a bent shape is also conceivable.
FIG. 8 is a plan view of the connection plate 36A of the second embodiment, and a part thereof is schematically shown. FIG. 9 is a cross-sectional view of the connection plate 36A of FIG. With reference to FIG. 8, FIG. 9, in this embodiment, the connection board 36A as a connection member is used instead of the above-mentioned connection board 36. FIG. The connection plate 36A is different from the connection plate 36 of the above-described embodiment in the following points, but is configured in the same manner in other points and functions similarly.

The connection board 36 </ b> A includes a single multilayer circuit board 110 and a plurality of cylindrical conductors 111 provided on the multilayer circuit board 110 and extending in the thickness direction of the multilayer circuit board 110.
The multilayer circuit board 110 has a plurality of layers stacked in the thickness direction of the multilayer circuit board 110, for example, in the present embodiment, first to ninth layers 121 to 129. The first to ninth layers 121 to 129 are stacked in this order.

The multilayer circuit board 110 includes a plurality of insulating plates 113, a plurality of conductor patterns 114, and a plurality of insulating films 115 in order to form the layers 121 to 129.
The first, third, fifth, seventh and ninth layers 121, 123, 125, 127 and 129 function as insulating layers. Specifically, each of the layers 121, 123, 125, 127, and 129 is constituted by an insulating plate 113.

The second, fourth, sixth, and eighth layers 122, 124, 126, and 128 function as layers including a conductor. Specifically, each of the layers 122, 124, 126, and 128 is composed of a conductor pattern 114 and an insulating film 115.
Each conductor pattern 114 is formed of a film-like conductor, for example, metal, along the insulating plate 113 adjacent in the plate thickness direction. The insulating film 115 is formed in a film shape along the insulating plate 113 adjacent in the plate thickness direction, and is provided around the conductor pattern 114 formed on the insulating plate 113.

Each conductor pattern 114 is electrically connected to the above-described cylindrical conductor 111. The conductor patterns 114 of the second, fourth, sixth, and eighth layers 122, 124, 126, and 128 are connected to different cylindrical conductors 111.
More specifically, the multilayer circuit board 110 has a plurality of insertion holes 116 that penetrate the multilayer circuit board 110 in the thickness direction. A cylindrical conductor 111 is formed of metal on the inner surface of the insertion hole 116. For example, the insertion hole 116 illustrated at the bottom in FIG. 9 passes through the plurality of insulating plates 113. Further, the insertion hole 116 passes through the conductor pattern 114 of the second layer 122. Thereby, the cylindrical conductor 111 provided in the insertion hole 116 is electrically connected to the conductor pattern 114 of the second layer 122. On the other hand, the insertion hole 116 passes through the insulating film 115 of the other layers including the conductor, that is, the fourth, sixth, and eighth layers 124, 126, and 128.

The conductive pattern 114 of the second layer 122 and the plurality of cylindrical conductors 111 electrically connected thereto constitute the first conductor 81 for U phase.
The conductive pattern 114 of the fourth layer 124 and the plurality of cylindrical conductors 111 electrically connected thereto constitute a second conductor 82 for V phase.
The conductive pattern 114 of the sixth layer 126 and the plurality of cylindrical conductors 111 electrically connected thereto constitute a W-phase third conductor 83.

The conductive pattern 114 of the eighth layer 128 and the plurality of cylindrical conductors 111 electrically connected thereto constitute a fourth conductor 84 for a neutral point. In addition, the plurality of insulating plates 113 and the plurality of insulating films 115 constitute an insulator 85.
In other words, the connection plate 36A, like the connection plate 36, is a first conductor 81 for the U phase, a second conductor 82 for the V phase, and a third conductor 83 for the W phase. And it can be said that it has the 4th conductor 84 for neutral points, and the insulator 85. FIG.

  Further, the first conductor 81 has a first terminal 87, a second terminal 88, and a connection portion 89. The second conductor 82 has a third terminal 91, a fourth terminal 92, and a connection portion 93. The third conductor 83 has a fifth terminal 95, a sixth terminal 96, and a connection portion 97. The fourth conductor 84 includes a seventh terminal 99, an eighth terminal 100, a ninth terminal 101, and a connection portion 97.

The connecting portions 89, 93, 97, 102 of the first to fourth conductors 81-84 are formed by the conductor patterns 114 of the corresponding layers 122, 124, 126, 128 described above. Each terminal 87, 88, 91, 92, 95, 96, 99, 100, 101 is formed by a corresponding cylindrical conductor 111.
In the present embodiment, the first, third, and fifth terminals 87, 91, and 95 for feeding the corresponding connection plate 36A are disposed in the plane of the connection plate 36A. The first, third, and fifth terminals 87, 91, and 95 and the linear terminal 72A of the other connector 39 are integrally formed by soldering, for example, and are electrically connected to each other.

  In the present embodiment, the connection plate 36A includes the second, fourth, sixth, and eighth layers 122, 124, 126, and 128 including the conductor pattern 114 as a conductor, and the first as an insulating layer. It includes a multilayer circuit board 110 in which first, third, fifth, seventh and ninth layers 121, 123, 125, 127 and 129 are alternately laminated. In this case, since the multilayer circuit board 110 is used for the connection board 36A, the connection board 36A is reduced in size.

FIG. 10 is a plan view of the connection member 130 of the third embodiment. FIG. 11 is a schematic exploded view of the connection member 130 of FIG. 12 is a cross-sectional view taken along the line XII-XII in FIG. In this embodiment, the connection member 130 is used in place of the connection plate 36 described above.
Similar to the connection plate 36, the connection member 130 includes a first conductor 81 for U phase, a second conductor 82 for V phase, a third conductor 83 for W phase, A fourth conductor 84 for dots and an insulator 85 are provided. The first conductor 81 has a first terminal 87, a second terminal 88, and a connection portion 89. The second conductor 82 has a third terminal 91, a fourth terminal 92, and a connection portion 93. The third conductor 83 has a fifth terminal 95, a sixth terminal 96, and a connection portion 97. The fourth conductor 84 includes a seventh terminal 99, an eighth terminal 100, a ninth terminal 101, and a connection portion 102.

The above-described portions of the connection member 130 are different from the corresponding portions of the connection plate 36 of the above-described embodiment in the following points, but are configured in the same manner in other points and function similarly. .
The connection member 130 is constituted by an electric wire assembly. The electric wire assembly includes a plurality of covered electric wires 131 and a plurality of holding members 132 that hold these covered electric wires 131. The covered electric wire 131 includes a metal wire 133 and an insulating covering member 134 that covers the metal wire 133.

Each of the first to fourth conductors 81, 82, 83, 84 is formed of a metal wire 133 of a covered electric wire 131 that is different from each other. The insulator 85 includes the insulating covering members 134 of the plurality of covered electric wires 131 and the plurality of holding members 132.
Each covered electric wire 131 has an annular shape. The two covered electric wires 131 have an annular shape with a relatively small diameter. These two covered electric wires 131 have the same diameter. The remaining two covered electric wires 131 have an annular shape with a relatively large diameter. The diameters of the remaining two covered wires 131 are equal to each other.

  In addition, the metal wire 133 has an annular main portion 135 and a plurality of convex portions 136 protruding from the main portion 135. The main body 135 is covered with an insulating covering member 134. The plurality of convex portions 136 are arranged apart from each other in the circumferential direction of the metal wire 133. Each protrusion 136 of the metal wire 133 of the relatively small-diameter covered electric wire 131 protrudes inward in the radial direction of the metal wire 133. Each convex part 136 of the metal wire 133 of the relatively large diameter covered electric wire 131 protrudes outward in the radial direction of the metal wire 133. In the vicinity of each convex portion 136, the insulating covering member 134 is removed.

The connecting portions 89, 93, 97, 102 of the first to fourth conductors 81 to 84 are formed by the main portion 135 of the corresponding metal wire 133. Each terminal 87, 88, 91, 92, 95, 96, 99, 100, 101 of each of the first to fourth conductors 81 to 84 is formed by a convex portion 136 of the corresponding metal wire 133.
The plurality of holding members 132 are spaced apart from each other in the circumferential direction of the covered electric wire 131. Each holding member 132 has a plurality of, for example, four holding holes 138. Each holding hole 138 holds a single covered electric wire 131. The four holding holes 138 are arranged in a grid in the axial direction and the radial direction of the motor housing 32.

  The four covered electric wires 131 are arranged concentrically by the plurality of holding members 132. At the same time, the two covered wires 131 having a relatively small diameter are arranged in the axial direction S 1 of the motor housing 32. The two relatively large-diameter covered electric wires 131 are arranged in the axial direction S1 of the motor housing 32. At the same time, one relatively large-diameter covered wire 131 and one relatively small-diameter covered wire 131 are opposed to each other in the radial direction R1 of the motor housing 32, and these mutually in the radial direction R1. The two covered electric wires 131 facing each other are arranged at the same position with respect to the axial direction S1 of the motor housing 32. The other relatively covered wire 131 having a larger diameter and the other covered wire 131 having a relatively smaller diameter are also arranged in the same manner.

In the present embodiment, the first, third, and fifth terminals 87, 91, and 95 for feeding the corresponding connecting members 130 and the linear terminal 72A of the other connector 39 are, for example, soldered. Are integrally formed by caulking or the like and are electrically connected to each other.
In the connection member 130 of the present embodiment, since the inexpensive covered electric wire 131 is used, the manufacturing cost of the connection member 130 can be reduced.

Since the holding member 132 holds the four covered electric wires 131 in a grid, the connection member 130 can be appropriately downsized in both the radial direction R1 and the axial direction S1 of the electric motor 23. As a result, the connecting member 130 and, consequently, the electric power steering device 1 can be miniaturized.
FIG. 13 is a schematic diagram of a schematic configuration of an electric power steering apparatus 1D as a vehicle steering apparatus according to the fourth embodiment. FIG. 14 is a cross-sectional view of the main part of FIG. 13 and mainly shows an electric motor 23D.

In the present embodiment, the electric motor 23 </ b> D is provided at the upper end portion of the steering shaft 3. The steering member 2 is provided with a torque sensor 20D. Accordingly, the housing 27 of the steering column 25 is abolished, and the input shaft 17, the output shaft 18 and the torsion bar 19 are abolished.
The steering member 2 includes a hub 144 at the center, an annular rim 145, and a plurality of spokes 146 that connect the rim 145 and the hub 144.

  The electric motor 23D is different from the above-described electric motor 23 in the following points, and is the same in other points. The electric motor 23 </ b> D has a pair of output shafts 148 that are rotatably supported by the motor housing 32. The rotor core 63 is coaxially connected to the pair of output shafts 148 via the pair of connecting members 65. One output shaft 148 is connected to the hub 144 of the steering member 2 so as to be able to rotate together. The other output shaft 148 of the electric motor 23D is coupled to the upper end portion of the steering shaft 3 so as to be able to rotate together.

  A motor housing 32 of the electric motor 23 </ b> D is fixed to an upper end portion in the axial direction of the steering column 25. With respect to the axial direction of the steering shaft 3, the electric motor 23 </ b> D is disposed between the steering column 25 and the steering member 2. In addition, at least a part (a part in the present embodiment) of the electric motor 23 </ b> D is disposed inside the rim 145 of the steering member 2.

  The torque sensor 20 </ b> D is interposed between the spoke 146 of the steering member 2 and the rim 145. The torque sensor 20D includes a pressure sensitive element (not shown). The steering torque is transmitted from the rim 145 to the spoke 146. At this time, at least a part of the steering torque (a part in the present embodiment) is transmitted from the rim 145 to the spoke 146 via the torque sensor 20D. At this time, the part of the steering torque is detected by the torque sensor 20D.

  For example, when the steering torque acts on the rim 145, the circumferential pressing force acts on a pair of opposed surfaces that are provided on the spoke 146 and the rim 145 and that are opposed to each other in the circumferential direction. A torque sensor 20D is interposed between the pair of opposed surfaces. The circumferential pressing force is detected by the pressure sensitive element. The above-mentioned pressing force changes according to the steering torque, and the output signal of the pressure sensitive element changes according to the magnitude of this pressing force. Therefore, the steering torque can be detected based on the output signal of the pressure sensitive element. In addition, a pair of pressure sensitive elements is provided to detect steering torque in both directions.

  As the torque sensor 20D, a sensor that detects a force acting on a joint portion between the spoke 146 and the rim 145 of the steering member 2 or a vicinity thereof can be used. Further, as the torque sensor 20D, a sensor that detects distortion generated in the coupling portion or the vicinity thereof may be used. Further, the torque sensor 20 </ b> D may be provided at all joints between the spokes 146 and the rim 145 of the steering member 2.

The connection plate 36 is disposed so as to face the outer surface 68 of the end wall 50 of the motor housing 32 on the lower side in the axial direction, and is disposed inward in the radial direction of the steering shaft 3.
In the present embodiment, since the electric motor 23D is arranged at the upper part in the axial direction of the steering column 25, the electric motor 23D and the driver's seat are compared with the case where the electric motor 23D is arranged at the lower part in the axial direction of the steering column 25. Interference with the peripheral members is less likely to occur. Therefore, the electric power steering apparatus can be easily applied to more types of vehicles.

  Here, the above-mentioned peripheral members are members disposed around the electric power steering apparatus 1D in the driver's seat, and are, for example, an instrument panel, a lean hose, wiring, and an air outlet forming member of an air conditioner. In addition, the above-mentioned lean hose is a structural member which comprises a part of motor vehicle arrange | positioned in the front part of a passenger compartment, and is a metal cylindrical member extended along the left-right direction of a motor vehicle.

  Further, with respect to the axial direction of the steering shaft 3, a part of the electric motor 23D and the rim 145 of the steering member 2 are arranged at the same position. In addition, a part of the electric motor 23 </ b> D is disposed inside the rim 145 of the steering member 2. In addition, the electric motor 23D directly drives the steering shaft 3 without using a speed reducer. As a result, the electric power steering device 1D can be reduced in size.

In addition, any one of the connection plate 36 as each modification of the first embodiment, the connection plate 36A of the second embodiment, and the connection member 130 of the third embodiment is used as the electric motor of the fourth embodiment. You may apply to 23D.
Moreover, each connection board 36 and 36A and the connection member 130 of each above-mentioned embodiment should just contain at least one of the 1st-4th conductors 81-84. In addition, each of the connection plates 36 and 36A and the connection member 130 of each of the above-described embodiments may be directly fixed to the end wall 50 as an object to be fixed, or may be fixed indirectly. In addition, each connection plate 36, 36 </ b> A and connection member 130 of each of the above-described embodiments may be opposed to the outer surface 68 of the end wall 51 instead of the end wall 50. Further, the above-described fixing target may be a member other than the end wall 50, for example, the end wall 51, the cylindrical member 49, or the steering column 25.

  In the first to fourth embodiments described above, the connection plates 36 and 36A and the connection member 130 facing the outer surface 68 of the end wall 50 of the motor housing 32 are electrically connected to a so-called column assist type electric power steering device. Although the example applied to the motors 23 and 23D has been described, the present invention is not limited to this, and each of the connection plates 36 and 36A and the connection member 130 described above is an electric motor of a so-called pinion assist type electric power steering device or a so-called rack assist. The present invention may be applied to an electric motor of an electric power steering device of the type.

  In the above-described embodiment, the example in which the present invention is applied to the electric power steering apparatus 1 that outputs the output of the electric motors 23 and 23D as the steering assist force has been described, but the present invention is not limited thereto. For example, a transmission ratio variable mechanism that includes a transmission ratio variable mechanism capable of changing a ratio of a steered wheel turning angle to a steering angle of a steering member, and that uses an output of an electric motor to drive the transmission ratio variable mechanism, is used for vehicle steering. Even if the present invention is applied to a device, a steer-by-wire type vehicle steering device in which the mechanical connection between the steering member and the steered wheel is released and the steered wheel is steered by the output of the electric motor, etc. Good. In addition, various changes can be made within the scope of the matters described in the claims.

1 is a schematic diagram of a schematic configuration of an electric power steering apparatus as a vehicle steering apparatus according to a first embodiment of the present invention. It is sectional drawing of the principal part of FIG. 1, and mainly shows an electric motor. It is a top view of the connection board of FIG. It is sectional drawing of the IV-IV cross section of FIG. It is an exploded view of the connection board of FIG. It is a top view of the modification of a connection board. It is sectional drawing of the VII-VII cross section of FIG. It is a top view of the connection board of a 2nd embodiment. It is sectional drawing of the connection board of FIG. It is a top view of the connection board of a 3rd embodiment. It is a typical exploded view of the connection board of FIG. It is sectional drawing of the XII-XII cross section of FIG. It is a schematic diagram of a schematic configuration of an electric power steering device as a vehicle steering device of a fourth embodiment. It is sectional drawing of the principal part of FIG. 13, and mainly shows an electric motor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1D ... Electric power steering apparatus (steering apparatus for vehicles), 3 ... Steering shaft (steering shaft), 23, 23D ... Electric motor, 30 ... Rotor, 31 ... Stator, 32 ... Motor housing, 34 ... Stator core, 35 ... Coil, 36, 36A ... connection board, 37 ... external wiring, 38, 39 ... connector (connection member), 50, 51 ... end wall, 68 ... (outside wall) outer surface, 72 ... terminal (extending projection), 104 DESCRIPTION OF SYMBOLS ... Metal plate, 106 ... Main part, 110 ... Multilayer circuit board, 113 ... Insulating plate, 114 ... Conductor pattern (conductor), 121, 123, 125, 127, 129 ... Insulating layer, 122, 124, 126, 128 ... a layer containing a conductor.

Claims (5)

A hollow steering column that surrounds the steering shaft and rotatably supports the steering shaft;
And an electric motor for applying a steering force to the steering shaft,
The electric motor includes a rotor that can rotate along the same axis as the steering shaft, a stator core that faces the rotor, a stator that includes a coil wound around the stator core, a cylindrical motor housing that houses the rotor and the stator, Including a connection plate for connecting the coil,
The steering column includes a cylindrical portion that accommodates at least a part of a torque sensor that detects a steering torque and protrudes in an axial direction from an end wall of the motor housing,
The connection plate is disposed in the open space surrounding the cylindrical portion at the outside of the torque sensor in the radial direction of the cylindrical portion, a steering vehicle, wherein opposing Tei Rukoto the outer surface of the end wall of the motor housing apparatus. In claim 1,
A connecting member for connecting the external wiring for supplying power to the electric motor and the coil;
The vehicle steering apparatus, wherein the connection member includes a terminal formed integrally with the connection board. In claim 2,
The connection plate includes a plurality of metal plates,
The terminal includes an extending protrusion extending from each metal plate,
Each of the extending protrusions and the corresponding metal plate are integrally formed of a single material. In claim 3,
The connection board includes a plurality of insulating plates,
Each of the metal plates includes a flat plate-shaped main portion,
A steering apparatus for a vehicle, wherein a main part of the metal plate and the insulating plate are alternately laminated.   3. The vehicle steering apparatus according to claim 1, wherein the connection board includes a multilayer circuit board in which layers including conductors and insulating layers are alternately stacked.

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