JP2009241787A - Steering device for vehicle - Google Patents

Abstract

The present invention provides a vehicle steering apparatus that is compact and has good mountability on a vehicle.
An ECU as a control device and a torque sensor as a steering state detection sensor are housed in an integral housing including a motor housing. The motor chamber 22 is partitioned by the motor housing body 26 and the first housing 23 that constitute the motor housing 25. The first housing 23 and the second housing 24 define a storage chamber 21 in which the ECU 12 is stored. The torque sensor 11 supported by the sensor housing 27 is disposed across the accommodation chamber 21 and the motor chamber 22.
[Selection] Figure 1

Description

  The present invention relates to a vehicle steering apparatus.

An electric power steering device as a vehicle steering device assists a driver's steering with an electric motor. That is, the steering state of the steering member is detected by various sensors and the like, and the control device controls the electric motor based on the detected value, so that a steering assist force is applied to the steering mechanism.
As an electromagnetic booster for an electric power steering apparatus, it has been proposed to arrange an electric motor on the same axis as the steering shaft and to arrange a control circuit in the case of the electromagnetic booster (for example, Patent Document 1). See).
Japanese Patent Publication No. 7-29611

In Patent Document 1, a torque sensor, a control device, and an electric motor are arranged in this order, and the torque sensor is arranged at a position separated from the electric motor and the control device with respect to the axial direction of the steering shaft. For this reason, there exists a problem that it enlarges in the axial direction of a steering shaft.
The present invention has been made based on such a background, and an object of the present invention is to provide a vehicle steering apparatus that is small in size and has good mountability on a vehicle.

  To achieve the above object, the present invention provides an electric motor (18) for obtaining a steering force, a steering state detection sensor (11; 11A; 11B; 11C) for detecting a steering state, and a steering state detection sensor. And a control device (12) for controlling the driving of the electric motor based on the detection signal from the motor, the electric motor being coaxial with the steering shaft (6) rotating in conjunction with the steering member (2). A rotor (19; 19A) provided rotatably, a stator (20) opposed to the rotor, and a motor housing (25) defining a motor chamber (22) in which the rotor and the stator are accommodated, and A housing (21) in which a control device is housed is formed in an integral housing (H) including a motor housing, and a steering state detection sensor is accommodated in the integral housing. With respect to the axial direction (X1) of the steering shaft, at least a portion of the steering state detecting sensor and the at least one of a portion of the accommodating chamber and the motor chamber and is characterized in that it is arranged in the same position.

  According to the present invention, since the control device and the steering state detection sensor are accommodated in an integral housing including the motor housing, it is possible to realize downsizing and simplification of the structure, and to reduce the manufacturing cost. In particular, with respect to the position of the steering shaft in the axial direction, at least a part of the steering state detection sensor and at least one part of the storage chamber and the motor chamber of the control device are arranged so as to overlap each other. Further downsizing can be achieved with respect to the direction, and as a result, it can be easily mounted on a vehicle. Further, since the electric motor, the steering state detection sensor, and the control device can be arranged close to each other, the wiring length of the signal line connecting them can be shortened, and electromagnetic noise can be reduced.

Examples of the steering state detection sensor include a torque sensor that detects a steering torque and a steering angle sensor that detects a steering angle.
Further, with respect to the axial direction of the steering shaft, the storage chamber may be disposed above the motor chamber, and the steering state detection sensor may be disposed so as to straddle the storage chamber and the motor chamber. ). In this case, a significant reduction in size can be achieved with respect to the axial direction of the steering shaft. It is also possible to connect the torque sensor and the control device or between the electric motor and the control device only with internal wiring.

Further, with respect to the axial direction of the steering shaft, the storage chamber may be disposed above the motor chamber, and the steering state detection sensor may be disposed in the motor chamber. In this case, since the steering state detection sensor is arranged in the motor chamber, it is possible to achieve downsizing.
Further, the storage chamber may be disposed above the motor chamber with respect to the axial direction of the steering shaft, and the steering state detection sensor may be disposed in the storage chamber of the control device. In this case, since the steering state detection sensor is disposed in the storage chamber of the control device, it is possible to achieve downsizing.

Further, with respect to the axial direction of the steering shaft, the storage chamber may be disposed below the motor chamber, and at least a part of the steering state detection sensor may be disposed in the motor chamber. In this case, since at least a part of the steering state detection sensor is disposed in the motor chamber, it is possible to achieve downsizing.
In the above description, the alphanumeric characters in parentheses represent reference numerals of corresponding components in the embodiments described later, but the scope of the claims is not limited by these reference numerals.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
FIG. 1 is a schematic diagram showing a schematic configuration of an electric power steering apparatus 1 as a vehicle steering apparatus according to an embodiment of the present invention.
Referring to FIG. 1, an electric power steering apparatus 1 includes a steering member 2 including a steering wheel, a steering mechanism 4 that steers the steered wheels 3 in conjunction with the rotation of the steering member 2, and steering of the driver. And a steering assist mechanism 5 for assisting. The steering member 2 and the steering mechanism 4 are mechanically coupled via a steering shaft 6 as a steering shaft and an intermediate shaft 7 as a steering shaft.

In the present embodiment, the steering assist mechanism 5 will be described based on an example in which an assist force (steering assist force) is applied to the steering shaft 6. However, the present invention is applied to the intermediate shaft 7 described above. It is possible to apply to the structure which gives Assistance, and the structure which gives assist force to the pinion axis | shaft 13 as a steering axis mentioned later.
The steering shaft 6 extends linearly. The steering shaft 6 includes an input shaft 8 connected to the steering member 2 and an output shaft 9 connected to the intermediate shaft 7 via a universal joint. The input shaft 8 and the output shaft 9 are connected via a torsion bar 10 so as to be relatively rotatable on the same axis. That is, when a steering torque of a certain value or more is input to the steering member 2, the input shaft 8 and the output shaft 9 rotate in the same direction while rotating relative to each other.

  A torque sensor 11 as a steering state detection sensor disposed around the steering shaft 6 detects the steering torque input to the steering member 2 based on the relative rotational displacement amounts of the input shaft 8 and the output shaft 9. The torque detection result of the torque sensor 11 is input to an ECU 12 (Electronic Control Unit) as a control device. Further, a vehicle speed detection result from a vehicle speed sensor (not shown) is input to the ECU 12. The intermediate shaft 7 connects the steering shaft 6 and the steering mechanism 4.

The steered mechanism 4 includes a rack and pinion mechanism including a pinion shaft 13 and a rack shaft 14 as a steered shaft. A steered wheel 3 is connected to each end of the rack shaft 14 via a tie rod 15 and a knuckle arm (not shown).
The pinion shaft 13 is connected to the intermediate shaft 7 via a universal joint. The pinion shaft 13 rotates in conjunction with the steering of the steering member 2. A pinion 16 is connected to the tip of the pinion shaft 13 (the lower end in FIG. 1).

  The rack shaft 14 extends linearly along the left-right direction of the automobile. A rack 17 that meshes with the pinion 16 is formed in the middle of the rack shaft 14 in the axial direction. By the pinion 16 and the rack 17, the rotation of the pinion shaft 13 is converted into the axial movement of the rack shaft 14. The steered wheel 3 can be steered by moving the rack shaft 14 in the axial direction.

When the steering member 2 is steered (rotated), this rotation is transmitted to the pinion shaft 13 via the steering shaft 6 and the intermediate shaft 7. The rotation of the pinion shaft 13 is converted into an axial movement of the rack shaft 14 by the pinion 16 and the rack 17. Thereby, the steered wheel 3 is steered.
The steering assist mechanism 5 includes a steering assist electric motor 18 disposed coaxially with the steering shaft 6 as a steering shaft. The electric motor 18 includes a rotor 19 connected to the output shaft 9 so as to be able to rotate along with the output shaft 9, and an annular stator 20 surrounding the rotor 19.

When the electric motor 18 rotationally drives the output shaft 9, the rotation is transmitted to the pinion shaft 13 via the intermediate shaft 7. The rotation of the pinion shaft 13 is converted into the axial movement of the rack shaft 14. Thereby, the steered wheel 3 is steered. In other words, the steered wheels 3 are steered by rotating the output shaft 9 by the electric motor 18.
The electric motor 18 is controlled by the ECU 12. The ECU 12 controls the electric motor 18 based on a torque detection result from the torque sensor 11 and a vehicle speed detection result from a vehicle speed sensor (not shown). Specifically, the ECU 12 determines the target assist amount by using a map in which the relationship between the torque and the target assist amount is stored for each vehicle speed, and controls the assist force generated by the electric motor 18 to approach the target assist amount. To do.

  A feature of the present embodiment is that an ECU 12 as a control device and a torque sensor 11 as a steering state detection sensor are housed in an integral housing H including a motor housing 25 of the electric motor 18. is there. Further, with respect to the axial direction X1 of the steering shaft 6 as a steering shaft, the torque sensor 11 is disposed so as to straddle the accommodation chamber 21 and the motor chamber 22 in which the ECU 12 is accommodated.

  In the present embodiment, the torque sensor 11 will be described in accordance with an aspect in which it extends over the accommodation chamber 21 and the motor chamber 22 of the ECU 12, but in the present invention, the steering shaft (the steering shaft 6, the intermediate shaft 7, the pinion) With respect to the axial direction of any of the shafts 13), at least a part of the steering state detection sensor (which may be the torque sensor 11 or the steering angle sensor) and the storage chamber 21 of the ECU 12. And at least one part of the motor chamber 22 should just be arrange | positioned in the same position.

  The integral housing H is configured by combining the first housing 23, the second housing 24, and the motor housing body 26. The first housing 23 and the second housing 24 that are in contact with each other (for example, in a state in which the end surfaces of each other are in contact with each other or in a state in which the end portions are fitted together) constitute a housing that defines the housing chamber 21. ing.

That is, the first housing 23 and the second housing 24 constituting the housing for housing the ECU 12 are in contact with each other (directly engaged), and another housing is provided between the housings 23 and 24. No housing is present. As a result, a significant reduction in size is achieved.
On the other hand, the motor housing 25 of the electric motor 18 includes a cylindrical motor housing body 26 and the first housing 23 described above. Specifically, the first housing 23 that is a part of the housing for housing the ECU 12 is integrally formed of at least a part of the motor housing 25 of the electric motor 12 with a single material. In other words, at least a part of the motor housing 25 is also used as a part of the housing for housing the ECU 12. The motor housing body 26 and the first housing 23 define a motor chamber 22 in which the rotor 19 and the stator 20 are accommodated.

A cylindrical sensor housing 27 in which the torque sensor 11 is accommodated extends through the accommodation chamber 21 and into the motor chamber 22. Thereby, as described above, the torque sensor 11 is disposed so as to straddle the accommodation chamber 21 and the motor chamber 22 of the ECU 12 with respect to the axial direction X1 of the steering shaft 6 as the steering shaft. The first housing 23, which is a part of the motor housing 25, includes an outer peripheral wall 92 having, for example, a square ring shape, and a partition wall 77 as a bottom wall. The second housing 24 combined with the first housing 23 has an outer peripheral wall 28 and a top wall 29 that form, for example, a square ring.

The steering shaft 6 includes a cylindrical upper shaft 31, a cylindrical lower shaft 32, and the input shaft 8 and the output shaft 9 arranged on the same axis. A part of the lower shaft 32 is fitted inside the upper shaft 31, and the upper shaft 31 and the lower shaft 32 are connected to be able to rotate together.
A part of the input shaft 8 is fitted inside the output shaft 9, and the input shaft 8 and the output shaft 9 are connected to each other via a torsion bar 10 inserted through the insides of both shafts 8 and 9. Has been.

Specifically, one end of the torsion bar 10 and the input shaft 8 are connected by a connecting member 33 so as to be able to rotate together. As the connecting member 33, a pin penetrating the one end of the torsion bar 10 and the input shaft 8 in the radial direction can be used.
The other end of the torsion bar 10 and the output shaft 9 are connected by a connecting member 34 so as to be able to rotate together. As the connecting member 34, a pin that penetrates the other end of the torsion bar 10 and the output shaft 9 in the radial direction can be used.

A part of the input shaft 8 is fitted inside the lower shaft 32, and the lower shaft 32 and the input shaft 8 are connected to each other by the connecting member 33 so as to be able to rotate together. That is, the lower shaft 32, the input shaft 8, and the one end of the torsion bar 10 are connected by a common connecting member 33.
The torque sensor 11 is disposed around the fitting portion of the input shaft 8 and the output shaft 9. The torque sensor 11 detects the torque input to the steering member 2 based on the magnetic resistance that changes according to the relative rotation amount of the input shaft 8 and the output shaft 9. A cylindrical sensor housing 27 that houses the torque sensor 11 passes through the housing chamber 21 of the ECU 12 and enters the motor chamber 22. A part of the sensor housing 27 is disposed radially inward of the rotor 19 of the electric motor 18, and the housing H is made small with respect to the axial direction X <b> 1 of the steering shaft 6.

The steering shaft 6 is rotatably supported by a steering column 39 via a plurality of bearings 35, 36, 37, and 38. Specifically, the steering column 39 is constituted by a cylindrical jacket 40 and the housing H described above.
The jacket 40 includes an upper jacket 41 and a lower jacket 42 that are fitted to each other. The upper jacket 41 is fitted to one end of the lower jacket 42, and the sensor housing 27 is fitted and fixed to the other end of the lower jacket 42.

The upper jacket 41 is fixed to the vehicle body side member 43. The motor housing body 26 of the housing H is fixed to the vehicle body side member 44.
The upper jacket 41 rotatably supports the upper shaft 31 via the bearing 35. The sensor housing 27 supports the input shaft 8 through a bearing 36 in a rotatable manner, and supports the output shaft 9 through a bearing 37 in a rotatable manner. The motor housing body 26 supports the output shaft 9 through a bearing 38 so as to be rotatable.

The end surfaces of the first housing 23 and the second housing 24 are abutted with each other, and the both end surfaces are sealed with an annular seal member 45.
The first housing 23 includes a first inner wall surface 101 that defines a part of the storage chamber 21, and the second housing 24 includes a second inner wall surface 102 that defines a part of the storage chamber 21, and The first inner wall surface 101 and the second inner wall surface 102 are opposed to the axial direction X1 of the steering shaft 6.

The second inner wall surface 102 of the second housing 24 is formed by an annular plane, and the annular plane is orthogonal to the central axis C1 of the steering shaft 6 and surrounds the central axis C1. Yes. Moreover, ECU12 as a control apparatus is arrange | positioned around said center axis line C1.
In the present embodiment, a brushless motor is used as the electric motor 18. The electric motor 18 includes the motor housing 25, the rotor 19 and the stator 20 accommodated in the motor housing 25.

  The rotor 19 includes an annular rotor core 66 attached to the outer periphery of the output shaft 9 so as to be able to rotate along with the rotor, and a rotor magnet 67 made of, for example, an annular permanent magnet attached to the outer periphery of the rotor core 66 so as to be able to rotate along with the rotor. Yes. In the rotor magnet 67, a plurality of magnetic poles are arranged side by side in the circumferential direction. These magnetic poles are configured so that the N pole and the S pole are alternately switched in the circumferential direction of the rotor 19.

  The stator 20 is fixed to the inner periphery of the motor housing body 26 of the motor housing 25. The stator 20 includes a stator core 68 fixed to the inner periphery of the motor housing body 26 and a plurality of coils 69. Stator core 68 includes an annular yoke and a plurality of teeth protruding radially inward from the inner periphery of the yoke. Each coil 69 is wound around a corresponding tooth.

  Further, in the motor chamber 22 defined by the motor housing main body 26 and the first housing 23 of the motor housing 25, an annular or C-shaped bus bar 71 is accommodated. The coil 69 wound around each tooth is connected to the bus bar 71. The bus bar 71 is a conductive connection material used for a connection portion between each coil 69 and the current application line, and the bus bar 71 functions as a power distribution member for distributing power from a power supply source (not shown) to each coil 69. To do.

  In the motor chamber 22, a rotational position detector 72 for detecting the rotational position of the rotor 19 is accommodated. The rotational position detection device 72 includes a stator 73 fixed to the outer periphery of the sensor housing 27 and a rotor 74 provided so as to be able to rotate with the output shaft 9 via a rotor core 66. The stator 73 and the rotor 74 are opposed to each other. As the rotational position detecting device 72, for example, a resolver can be used. A Hall element can also be used.

  The first housing 23, which is a part of the housing that partitions the storage chamber 21 of the ECU 12, includes a partition wall 77 that partitions the storage chamber 21 and the motor chamber 22 as a bottom wall. The partition wall 77 is provided with the first inner wall surface 101. A cylindrical projection 104 extends from the vicinity of the outer periphery of the partition wall 77 toward the motor housing body 26, and one end of the motor housing body 26 is fitted to the outer periphery of the cylindrical projection 104.

  A power board 78 and a control board 79 that constitute a part of the ECU 12 are accommodated and held in the accommodation chamber 21. On the power board 78, at least a part of a power circuit (for example, a switching element such as an FET) for driving the electric motor 18 is mounted. The bus bar 71 connected to each coil 69 is connected to the power board 78 via a bus bar terminal 82 that passes through the partition wall 77 of the first housing 23 and enters the storage chamber 21.

The cylindrical sensor housing 27 is inserted into the insertion hole 30 of the top wall 29 of the second housing 24 together with the lower jacket 42 described above. The sensor housing 27 is inserted into an insertion hole 79 a formed in the control board 79, and further inserted into an insertion hole 77 c in the partition wall 77 of the first housing 23.
In addition, the rotational position detection device 72 is connected to the control board 79 via a bus bar terminal 81 that passes through the partition wall 77 of the first housing 23 and enters the storage chamber 21. Further, the torque sensor 11 is connected to the control board 79 only by wiring (internal wiring) in the housing H via a terminal 46 that passes through the sensor housing 27 in the accommodation chamber 21.

  In the storage chamber 21, the power board 78 on which the power circuit is mounted is disposed relatively close to the first inner wall surface 101 among the first inner wall surface 101 and the second inner wall surface 102. That is, the partition wall 77 includes a thick portion 77a and a relatively thin portion 77b that have a relatively thick thickness t1 in the axial direction X1 of the steering shaft 6. The thick portion 77a is provided so as to protrude into the accommodation chamber 21.

The power board 78 is arranged close to or in contact with the first inner wall surface 101 in the thick portion 77a. Specifically, in the first inner wall surface 101, the thick portion 77 a is a seat portion 103 that receives the power board 78.
In the present embodiment, the power substrate 78 is in contact with the first inner wall surface 101 in the thick portion 77a so as to be capable of conducting heat, and the thick portion 77a is for releasing the heat of the power substrate 78. It functions as a heat sink.

The control board 79 is disposed between the second inner wall surface 102 of the second housing 24 and the power board 78 with respect to the axial direction X1 of the steering shaft 6. The power board 78 and the control board 79 are arranged at a predetermined interval with respect to the axial direction X1 of the steering shaft 6.
In the storage chamber 21, the storage space S1 formed between the thin wall portion 77b of the partition wall 77 of the first housing 23 and the control board 79 has a sufficient height with respect to the axial direction X1 of the steering shaft 6. is doing. Although not shown in FIG. 2, tall parts such as a capacitor 85 and a relay 86 shown in FIG. 3 to be described later are accommodated in the accommodation space S <b> 1, and effective use of the space in the accommodation chamber 21 is facilitated. It has been.

  Next, referring to FIG. 3 which is an exploded perspective view, a power circuit 82 for driving the electric motor 18 is mounted on the power board 78. The power circuit 82 mounted on the power substrate 78 includes a plurality of FETs 83 (electrolytic effect transistors) as heat generating elements. The power board 78 is composed of a multilayer board on which a circuit is mounted on one side, and the multilayer board includes a high heat conduction plate (not shown) made of, for example, an aluminum plate that is in surface contact with the thick portion 77a as a heat sink. It is out.

  A control circuit 84 for controlling the power circuit 82 that drives the electric motor 18 is mounted on the control board 79. The control circuit 84 mounted on the control board 79 is disposed around the central axis C <b> 1 of the steering shaft 6. The control circuit 84 includes a driver that controls each FET 83 of the power circuit 82 and a CPU that controls the driver. Further, the ECU 12 includes a plurality of capacitors 85 for removing ripples of current flowing through the electric motor 18, a relay 86 for cutting off current flowing through the electric motor 18 as necessary, and other non-heat generating elements. ing. The capacitor 85, the relay 86, and the like as non-heat generating elements constitute a subassembly supported by an annular synthetic resin holder (not shown) so that the mounting operation can be performed collectively on the first housing 23. It has become.

The first housing 23 is a substantially square box-shaped member having one end opened. Specifically, the first housing 23 includes the outer peripheral wall 92 having a substantially quadrangular annular shape, the square annular flange 88 projecting radially outward from one end of the outer peripheral wall 92, and the above-described bottom wall. And a partition wall 77.
In the storage chamber 21, an insertion hole 77 c through which the sensor housing 27 is inserted is formed at the center of the partition wall 77 as described above. The outer peripheral wall 92 extends from the outer peripheral edge of the partition wall 77.

  An end surface 88a (the upper surface in FIG. 3) of the flange 88 is flat. The sealing member 45 comes into contact with the end surface 88a. Further, the flange 88 has a plurality of (a pair in the present embodiment) bracket-shaped attachment portions 96 protruding outward in the radial direction. Each attachment portion 96 is formed with a screw insertion hole 97 that penetrates the attachment portion 96 in the thickness direction. A fixing screw (not shown) for fastening the first and second housings 23 and 24 is inserted into each screw insertion hole 97.

The outer peripheral wall 92 having a quadrangular annular shape has four side walls 111 to 114, and the mounting portion 96 is extended at the ends of a pair of opposing side walls 111 and 113. Further, the thick portion 77a of the partition wall 77 that functions as the heat sink is formed continuously on the inner surface of one side wall 111 on which the mounting portion 96 is extended.
Of the first inner wall surface 101, a portion in the thick portion 77 a constitutes a seat portion 103 that receives the power board 78. The seat portion 103 is in contact with a power substrate 78 having an FET 83 as a heat generating element so as to allow heat conduction. The heat of the heat generating element is released from the second housing 24 to the jacket 40 side from the power board 78 through the thick portion 77a and the attachment portion 96 constituting the heat sink.

In the mounting portion 96 used for fastening with the fixing screw (not shown), the contact area with respect to the second housing 24 is larger than that of the other portion of the flange 88. A thick wall portion 77a serving as a heat sink having a large heat capacity is provided continuously to the side wall 111 provided with the mounting portion 96.
For example, an electrical connector 94 for inputting a signal from a vehicle speed sensor to the ECU 12 is disposed on a part of the outer peripheral wall 92.

According to the present embodiment, the ECU 12 as the control device and the torque sensor 11 as the steering state detection sensor are housed in the integral housing H including the motor housing 25, so that downsizing and simplification of the structure are realized. Manufacturing cost can be reduced.
In particular, with respect to the position of the steering shaft 6 in the axial direction X1, the torque sensor 11 and at least one of the accommodation chamber 21 and the motor chamber 22 of the ECU 12 are arranged so as to overlap each other. Specifically, with respect to the axial direction X1 of the steering shaft 6, the torque sensor 11 is disposed so as to straddle the accommodation chamber 21 and the motor chamber 22, so that the electric power steering device 1 is connected to the axial direction of the steering shaft 6. The size can be further reduced with respect to X1. As a result, it becomes easy to mount on the vehicle.

  Further, since the electric motor 18, the torque sensor 11 and the ECU 12 can be arranged close to each other, the wiring length of the signal line connecting them can be shortened, and electromagnetic noise can be reduced. In particular, the electric motor 18, the torque sensor 11 and the ECU 12 can be connected to each other only through the bus bar terminals 82 and 81 and the terminal 46 as internal wiring, and electromagnetic noise can be greatly reduced.

  The first housing 23 that is at least a part of the motor housing 25 and the second housing 24 that is in contact with the first housing 23 form a housing chamber 21 of the ECU 12. That is, since another housing is not interposed between the first housing 23 and the second housing 24, the electric power steering device 1 can be reduced in size. Therefore, the mountability to a vehicle is good.

In addition, the rotational position detecting device 72 that detects the rotational position of the rotor 19 of the electric motor 18 is arranged at a position overlapping with a part of the sensor housing 27 and a part of the rotor 19 with respect to the axial direction X1 of the steering shaft 6. Also in this respect, the electric power steering apparatus 1 can be reduced in size with respect to the axial direction X1.
In addition, the second inner wall surface 102 of the second housing 24 that defines a part of the accommodation chamber 21 includes an annular plane that is orthogonal to the central axis C1 of the steering shaft 6 and surrounds the central axis C1. . That is, there is no unnecessary protrusion in the storage chamber 21 with respect to the axial direction X1 of the steering shaft 6. Therefore, even if the storage chamber 21 is small with respect to the axial direction X1, a sufficient internal volume as the storage chamber 21 can be secured, and the electric power steering device 1 can be miniaturized as much as possible.

Further, since the ECU 12 as the control device is arranged around the central axis C1 of the steering shaft 6, the space inside the storage chamber 21 can be used effectively for the arrangement of the ECU 12, and as a result, the axis of the steering shaft 6 can be used. With respect to the direction X1, the electric power steering apparatus 1 can be made smaller.
The first housing 23 includes a partition wall 77 that partitions the storage chamber 21 and the motor chamber 22, and a power board 78 is provided relatively close to the first inner wall surface 101 of the partition wall 77. Yes. In particular, the power substrate 78 is in contact with the first inner wall surface 101 in the thick portion 77a of the partition wall 77 so as to be capable of conducting heat. Therefore, by using the thick portion 77a of the partition wall 77 of the first housing 23 as a heat sink, the heat of the power board 78 having a heat generating element such as the FET 83 is contacted from the first housing 23 to the second housing. It can escape effectively to 24 side.

In the accommodation chamber 21, the accommodation space S1 facing the thin wall portion 77b of the partition wall 77 of the first housing 23 has a sufficient height with respect to the axial direction X1 of the steering shaft 6. In S1, effective use of the space in the storage chamber 21 is achieved by storing tall components such as the capacitor 85 and the relay 86 shown in FIG.
Next, FIG. 4 shows another embodiment of the present invention. The present embodiment is different from the embodiment of FIG. 1 as follows. That is, in the embodiment of FIG. 1, the torque sensor 11 is disposed so as to straddle the storage chamber 21 and the motor chamber 22 with respect to the axial direction X1 of the steering shaft 6. On the other hand, in the present embodiment, the entire torque sensor 11 </ b> A is disposed in the motor chamber 22. In the present embodiment, the same components as those in the embodiment of FIG.

  In the present embodiment, the same operational effects as the embodiment of FIG. 1 can be obtained. Specifically, since the torque sensor 11A as a steering state detection sensor is disposed in the motor chamber 22, the electric power steering device 1 can be reduced in size with respect to the axial direction X1 of the steering shaft 6. Therefore, it becomes easy to mount the electric power steering device 1 on the vehicle.

  In addition, since the electric motor 18, the torque sensor 11A, and the ECU 12 can be arranged close to each other, the wiring length of signal lines connecting them can be shortened, and electromagnetic noise can be reduced. In particular, the electric motor 18, the torque sensor 11A, and the ECU 12 can be connected to each other only through internal wiring, and electromagnetic noise can be significantly reduced.

  Next, FIG. 5 shows still another embodiment of the present invention. The present embodiment is different from the embodiment of FIG. 1 as follows. That is, in the embodiment of FIG. 1, the torque sensor 11 is disposed so as to straddle the storage chamber 21 and the motor chamber 22 with respect to the axial direction X1 of the steering shaft 6. In contrast, in the present embodiment, the entire torque sensor 11 </ b> B is disposed in the accommodation chamber 21.

  In the embodiment of FIG. 1, a part of the sensor housing 27 is disposed radially inward of the rotor 19 of the electric motor 18. On the other hand, in the present embodiment, the sensor housing 27 and the rotor 19A are separated from each other with respect to the axial direction X1 of the steering shaft 6. In the present embodiment, the same components as those in the embodiment of FIG.

  In the present embodiment, the same operational effects as the embodiment of FIG. 1 can be obtained. Specifically, since the torque sensor 11B as the steering state detection sensor is disposed in the storage chamber 21, the electric power steering device 1 can be reduced in size with respect to the axial direction X1 of the steering shaft 6. Therefore, it becomes easy to mount the electric power steering device 1 on the vehicle.

  In addition, since the electric motor 18, the torque sensor 11B, and the ECU 12 can be arranged close to each other, the wiring length of signal lines connecting them can be shortened, and electromagnetic noise can be reduced. In particular, the electric motor 18, the torque sensor 11B, and the ECU 12 can be connected to each other only through internal wiring, and electromagnetic noise can be significantly reduced.

  Next, FIG. 6 shows still another embodiment of the present invention. The present embodiment differs from the embodiment of FIG. 1 in that in the embodiment of FIG. 1, the storage chamber 21 is disposed above the motor chamber 22 with respect to the axial direction X1 of the steering shaft 6. On the other hand, in the present embodiment, the storage chamber 21 is disposed below the motor chamber 22 with respect to the axial direction X1 of the steering shaft 6.

  Further, in the embodiment of FIG. 1, the second housing 24, the first housing 23, and the motor housing body 26 are arranged in this order from the upper side to the lower side in the axial direction X1 of the steering shaft 6. H constituted. On the other hand, in the present embodiment, the motor housing body 26A, the first housing 23A, and the second housing 24A are arranged in this order from the upper side to the lower side in the axial direction X1 of the steering shaft 6 so as to be integrated. The housing H1 is configured. The first housing 23A and the second housing 24A constitute a housing 25A of the ECU 12.

In the present embodiment, at least a part of the torque sensor 11 </ b> C is disposed in the motor chamber 22. In the present embodiment, the same components as those in the embodiment of FIG.
Also in the present embodiment, the same operational effects as the embodiment of FIG. 1 can be obtained. Specifically, since at least a part of the torque sensor 11C is disposed in the motor chamber 22, the electric power steering device 1 can be reduced in size with respect to the axial direction X1 of the steering shaft 6. Therefore, it becomes easy to mount the electric power steering device 1 on the vehicle.

  Moreover, since the electric motor 18, the torque sensor 11C, and the ECU 12 can be arranged close to each other, the wiring length of the signal line connecting them can be shortened, and electromagnetic noise can be reduced. In particular, the electric motor 18, the torque sensor 11C, and the ECU 12 can be connected to each other only through internal wiring, and electromagnetic noise can be significantly reduced.

The steering shaft is not limited to the steering shaft 6 but may be the intermediate shaft 7 or the pinion shaft 13.
In each of the above embodiments, the steering state detection sensor is a torque sensor. However, the steering state detection sensor may be a steering angle sensor that detects the steering angle of the steering member 2. .

The present invention is not limited to the contents of the above embodiments, and various modifications can be made within the scope of the claims.
In the above-described embodiment, the example in which the present invention is applied to the electric power steering apparatus that outputs the output of the electric motor 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.

Further, at least a part of the power board 78 and the control board 79 of the ECU 12 may be molded with resin.
In the above-described embodiment, an example in which a brushless motor is used as the electric motor 18 has been described. However, the invention is not limited thereto, and a motor other than the brushless motor may be used as the electric motor 18.

It is a mimetic diagram showing a schematic structure of an electric power steering device as a vehicle steering device concerning one embodiment of the present invention. It is an illustration sectional view of the important section of an electric power steering device. It is a disassembled perspective view of the 1st housing and the components of ECU accommodated in this. It is a mimetic diagram showing a schematic structure of an electric power steering device as a steering device for vehicles concerning another embodiment of the present invention. It is a mimetic diagram showing a schematic structure of an electric power steering device as a steering device for vehicles concerning another embodiment of the present invention. It is a mimetic diagram showing a schematic structure of an electric power steering device as a steering device for vehicles concerning another embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electric power steering device (steering device for vehicles), 4 ... Steering mechanism, 5 ... Steering assist mechanism, 6 ... Steering shaft (steering shaft), X1 ... (steering shaft) axial direction, C1 ... Center axis, 7 ... intermediate shaft (steering shaft), 10 ... torsion bar, 11, 11A, 11B, 11C ... torque sensor, 12 ... ECU (control device), 13 ... pinion shaft (steering shaft), 18 ... electric motor, 19, 19A ... Rotor, 20 ... Stator, 21 ... Storage chamber (contains control device), 22 ... Motor chamber, 23, 23A ... First housing, 24, 24A ... Second housing, 25 ... Motor housing, 26, 26A ... Motor housing body, 27 ... Sensor housing, H, H1 ... Integral housing

Claims (5)

An electric motor to obtain steering force;
A steering state detection sensor for detecting a steering state;
A control device for controlling the drive of the electric motor based on a detection signal from the steering state detection sensor,
The electric motor divides a rotor provided coaxially with a steering shaft that rotates in conjunction with a steering member so as to be able to rotate together, a stator facing the rotor, and a motor chamber in which the rotor and the stator are accommodated. Including a motor housing,
A housing chamber containing the control device is formed in an integral housing including the motor housing,
A steering state detection sensor is housed in the integral housing.
A steering apparatus for a vehicle, characterized in that at least a part of a steering state detection sensor is disposed at the same position as a part of at least one of the storage chamber and the motor chamber with respect to the axial direction of the steering shaft.   In claim 1, with respect to the axial direction of the steering shaft, the storage chamber is disposed above the motor chamber, and the steering state detection sensor is disposed so as to straddle the storage chamber and the motor chamber. A vehicle steering apparatus.   2. The vehicle steering apparatus according to claim 1, wherein the storage chamber is disposed above the motor chamber with respect to the axial direction of the steering shaft, and the steering state detection sensor is disposed in the motor chamber.   The vehicle steering apparatus according to claim 1, wherein the storage chamber is disposed above the motor chamber with respect to the axial direction of the steering shaft, and the steering state detection sensor is disposed in the storage chamber.   2. The vehicle according to claim 1, wherein the housing chamber is disposed below the motor chamber with respect to the axial direction of the steering shaft, and at least a part of the steering state detection sensor is disposed in the motor chamber. Steering device.

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