JP2007106151A - Wheel device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel device which can optimally set a vehicle posture. <P>SOLUTION: This wheel device 1 is equipped with a motor 3, a wheel supporting member 5, a braking member, and an arm member 9. In this case, the motor 3 is arranged on a wheel 7, and rotationally drives or regeneratively brakes the wheel 7. The wheel supporting member 5 is connected with a vehicle body through a suspension, and rotatably supports the wheel 7. The braking member is arranged on the wheel supporting member 5, and frictionally brakes the wheel 7. One end of the arm member 9 is connected with the vehicle body, and the other end of which is connected with the housing 3a of the motor 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wheel device in which a motor for rotationally driving or regeneratively braking a wheel is provided.

Conventionally, a wheel support unit that is supported by a vehicle body via a suspension device and rotatably supports a wheel, a motor that is supported by the wheel support unit, and that rotates and drives the wheel, and is disposed on the wheel support unit and brakes the wheel. There is known a motor-deployed wheel device including a caliper that performs (see, for example, Patent Document 1). The wheel support portion and the suspension device receive the reaction force against the driving force of the motor and the reaction force against the braking force of the caliper.
JP 2004-90822 A

  By the way, an anti-squat angle is used as one design parameter for determining the pitching posture during vehicle acceleration. In addition, an anti-lift angle is used as one design parameter for determining the pitching posture during vehicle braking.

  In the conventional motor-equipped wheel device, the reaction force against the driving force (driving torque) of the motor and the reaction force against the braking force (braking torque) of the caliper are both received by the wheel support portion and the suspension device. For this reason, since both these reaction forces are received by the same member, the anti-squart angle during vehicle acceleration and the anti-lift angle during vehicle braking become the same angle θ (FIG. 4). Thereby, the pitching posture at the time of vehicle acceleration and the pitching posture at the time of vehicle braking cannot be set separately, and the degree of freedom in design can be hindered. Therefore, there is a possibility that the pitching posture during vehicle acceleration and vehicle braking cannot be set optimally.

  The present invention has been made to solve such problems, and it is a main object of the present invention to provide a wheel device capable of optimally setting the vehicle posture.

The object is as described in claim 1.
A motor disposed on the wheel for rotationally driving or regeneratively braking the wheel;
A wheel support member connected to the vehicle body via a suspension and rotatably supporting the wheel;
A brake device disposed on the wheel support member and configured to frictionally brake the wheel,
This is achieved by a wheel device comprising an arm member having one end connected to the vehicle body and the other end connected to the housing of the motor.

  In the present invention, one end of the arm member is connected to the vehicle body, and the other end is connected to the motor housing. On the other hand, the brake member is connected to the vehicle body via a wheel support member and a suspension. In this case, the reaction force of the driving force (driving torque) generated when the motor is driven to rotate is transmitted to the vehicle body via the arm member. Further, the reaction force of the braking force (braking torque) generated at the time of friction braking of the wheel by the brake member is transmitted to the vehicle main body via the wheel support member and the suspension. Thus, the reaction force of the driving force of the motor during vehicle acceleration differs from the reaction force of the braking force of the brake member during vehicle braking in how these forces are received. Therefore, when the vehicle is accelerated and when the vehicle is braked, for example, by separately setting the vehicle vertical force received by the wheel support member, the pitching posture during vehicle acceleration and when the vehicle is braked is set to an optimum value separately. can do. That is, the vehicle posture can be set optimally.

  Note that the regenerative braking refers to braking the wheel by the rotational resistance of the motor that is generated, for example, during power generation (regeneration) of the motor. The friction braking refers to braking the wheel by friction resistance when the brake member comes into contact with a disk rotor connected to the wheel, for example. Further, the wheel support member includes a carrier that rotatably supports the wheel, one end connected to the carrier, the other end connected to the vehicle body, and an arm such as a lower arm that supports the carrier so as to be swingable in the vehicle vertical direction, You may have.

In this case, as described in claim 2, the wheel device according to claim 1,
The arm member preferably transmits a reaction force generated by the rotation driving or the regenerative braking of the motor to the vehicle body.

Further, as described in claim 3, the wheel device according to claim 1 or 2,
It is preferable that the arm member is disposed so that an anti-squart angle α that determines a pitching posture during vehicle acceleration is different from an anti-lift angle β that determines a pitching posture during vehicle braking. Thereby, the pitching posture at the time of vehicle acceleration and vehicle braking can be individually set to an optimum value. That is, the vehicle posture can be set optimally. The anti-lift angle that determines the pitching posture during vehicle acceleration may be set different from the anti-dive angle that determines the pitching posture during vehicle braking.

Furthermore, as described in claim 4, the wheel device according to any one of claims 1 to 3,
The arm member may extend in the vehicle front-rear direction. Thereby, the reaction force of the driving force generated at the time of rotational driving or regenerative braking of the motor can be transmitted to the vehicle body via the arm member.

  ADVANTAGE OF THE INVENTION According to this invention, the wheel apparatus which can set a vehicle attitude | position optimally can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the accompanying drawings. Note that the basic concept, main hardware configuration, operating principle, basic control method, and the like of the wheel device and the suspension device are known to those skilled in the art, and thus detailed description thereof is omitted.

  FIG. 1 is a schematic cross-sectional view of a wheel device according to an embodiment of the present invention, showing a state where the wheel device is mounted on a left rear wheel. Note that the state in which the wheel device 1 is attached to the right rear wheel is substantially the same as that of the left rear wheel, and thus detailed description thereof is omitted.

  The wheel device 1 according to this embodiment includes a motor 3 that is disposed in the wheel 7 and that rotationally drives the wheel 7 or performs regenerative braking. Further, a wheel support member 5 that rotatably supports the wheel 7 is connected to the vehicle body side member via a suspension.

  The wheel 7 includes a wheel 7a formed of an aluminum alloy or the like in a cylindrical shape, and a tire 7b fitted into a rim portion of the wheel 7a and filled with air. The tire 7b is made of a rubber material or the like and is formed in an annular shape.

  The motor 3 includes a motor housing 3a disposed in the wheel 7a, and a stator that is disposed on the inner peripheral surface of the motor housing 3a and is formed of a coil or the like. Inside the stator, a rotor 3b is arranged coaxially while maintaining a slight clearance with the stator. The rotor 3b is rotatably supported by a pair of bearings (for example, roller bearings) 3c arranged at both ends of the motor housing 3a.

  For example, an AC synchronous motor is used as the motor 3. When electric power is supplied to the stator coil from the power source of the vehicle body, the rotor 3b holding the permanent magnet is rotated, and the drive shaft 3d connected to the rotor 3b is rotated. On the other hand, the motor 3 has a power generation function as a generator. At the time of power generation (regeneration) of the motor 3, a power generation resistance is loaded on the rotation of the rotor 3b, and this load acts on the rotation of the wheel 7 as a braking force.

  One end 9a of an arm member 9 such as a torque rod extending in the vehicle front-rear direction is connected to the lower end 3e of the motor housing 3a by a bolt and a nut via a bush. The other end 9b of the torque rod 9 is connected to the vehicle body side member by a bolt and a nut so as to be swingable via a bush. The reaction force generated when the motor 3 is rotationally driven or regeneratively braked is transmitted to the vehicle body side member via the motor housing 3a and the torque rod 9.

  A hat 11a of the disc rotor 11 and a hub flange 13a of the hub 13 are connected to the wheel 7a in this order from the outside of the vehicle by hub bolts and nuts. The hub 13 is connected to the drive shaft 3 d of the motor 3. A reduction gear made of a planetary gear or the like may be interposed between the hub 13 and the drive shaft 3d of the motor 3. The speed reducer decelerates the rotation of the drive shaft 3 d of the motor 3 at a predetermined reduction ratio and transmits it to the hub 13.

  The wheel support member 5 is disposed on the outer periphery of the motor 3 and has a substantially cylindrical carrier 5a that opens to the inside of the vehicle. A bearing 5b such as a roller bearing is disposed at the center of the substantially cylindrical carrier 5a, and this bearing 5b rotatably supports a drive shaft 3d of the motor 3.

  A brake caliper 5d having a substantially U-shaped cross section is attached to the upper end portion 5c of the carrier 5a so as to be slidable in the vehicle width direction. A pair of brake pads 5e is disposed on the inner surface of the U-shaped brake caliper 5d so as to sandwich the sliding surface of the disk rotor 11. When the brake pedal is depressed, the brake caliper 5d slides in the vehicle width direction, and the brake pad 5e of the brake caliper 5d is pressed against the sliding surface of the disc rotor 11. By this pressing, a frictional force is generated between the brake pad 5e and the sliding surface of the disk rotor 11, and the rotation of the disk rotor 11 is braked by this frictional force.

  One end of a lower arm 13 extending in the vehicle width direction is connected to the lower end portion 5f of the carrier 5a via a bush. The other end of the lower arm 13 is connected to the vehicle main body side member via a bush.

  One end of an upper arm 15 extending in the vehicle width direction is connected to the upper end portion 5c of the carrier 5a via a bush. The other end of the upper arm 15 is connected to the vehicle main body side member via a bush. In such a double wishbone suspension, the vehicle body side member supports the lower arm 13, the carrier 5a, and the upper arm 15 so as to be swingable in the vehicle vertical direction. The bush is made of a rubber member or the like, and has a vibration isolating function for preventing vibration input from the wheel 7 from being transmitted to the vehicle main body side member.

  One end of a damping element 17 such as a shock absorber extending in the vehicle vertical direction is connected to the lower arm 13 via a bush. The shock absorber 17 has a cylinder 17a in which an oil passage through which oil and the like flow is formed, and a piston 17b slidably disposed inside the cylinder 17a. The other end of the shock absorber 17 is connected to the vehicle body side member via a bush.

  An elastic element 19 such as a coil spring that absorbs vibration input from the road surface via the wheel 7 is coaxially disposed on the shock absorber 17. The shock absorber 17 has a function of attenuating the vibration of the coil spring 19.

  Next, the operation of the wheel device 1 configured as described above will be described.

  When the motor 3 is rotationally driven during acceleration of the vehicle, the driving force (driving torque) of the motor 3 is transmitted to the wheels 7 via the driving shaft 3d and the hub 13. On the other hand, the reaction force against the driving force of the motor 3 is transmitted to the vehicle body side member via the motor housing 3a and the torque rod 9.

  Further, during braking of the vehicle, a braking force (braking torque) acts on the disc rotor 11 from the brake pad 5e of the brake caliper 5d. The reaction force against the braking force is transmitted to the upper arm 15 and the lower arm 13 via the brake caliper 5d and the carrier 5a, and is transmitted to the vehicle body side member.

  Further, during braking of the vehicle by power generation (regeneration) of the motor 3, the reaction force due to the driving force of the motor 3 is transmitted to the vehicle body side member via the motor housing 3a and the torque rod 9.

  Due to the reaction force described above, the upper arm 15, the lower arm 13, the coil spring 19, and the shock absorber 17 (hereinafter referred to as “suspension”) are stroked in the vehicle vertical direction, and the vehicle pitches (the entire vehicle). Swings back and forth). In designing the vehicle, it is possible to improve the operability and comfort of the vehicle by optimally setting the pitching posture during vehicle acceleration and vehicle braking.

  For example, the anti-squat angle α is used as one design parameter for determining the pitching posture during vehicle acceleration. Further, the anti-lift angle β is used as one design parameter for determining the pitching posture during vehicle braking (FIG. 2).

  The anti-squart angle α and the anti-lift angle β can be obtained as follows, for example. First, the anti-lift line n3 connecting the intersection m of the swing axis n1 when the upper arm 15 swings and the swing axis n2 when the lower arm 13 swings, and the contact point p between the wheel 7 and the road surface Z. Ask for. An angle formed by the antilift line n3 and the road surface Z is an antilift angle β.

  Further, a line n4 connecting the intersection m of the swing axes n1 and n2 and the driving center r of the motor 3 or an extension line n5 extending this line n4 and an extension line n6 extending the torque rod 9 forward of the vehicle. Find the intersection point s. The virtual intersection point s is a point that supports the driving torque. The angle formed between the intersection point s, the anti-squat line n7 connecting the contact point p between the wheel 7 and the road surface Z, and the road surface Z is an anti-squat angle α. The intersection point s can be set at an arbitrary position depending on the arrangement method of the torque rod 9. For example, the intersection s between the extension line n6 of the torque rod 9 and the line n4 may be closer to the wheel than the intersection m.

  FIG. 3 is a diagram showing the relationship between the braking force F1 of the brake caliper 5d and the anti-lift angle β and the driving force F2 of the motor 3 and the anti-squart angle α.

As shown in FIG. 3, the braking force F1 acts on the wheel 7, for example, from the brake caliper 5d, during wheel braking, the braking force F1 by the brake caliper. 5d vehicle vertical force component F1 _y the coil spring 19 is subjected And the force component F1 _{β in} the anti-lift angle β direction. During vehicle braking, a rear lift that lifts the rear of the vehicle is generated by the force component F1 _{y in the} vehicle vertical direction.

On the other hand, when the driving force F2 acts on the wheel 7 from the motor 3, the driving force F2 of the motor 3 is received by the coil spring 19 when the motor is driven (accelerating the vehicle) or the motor is regenerating (braking the vehicle). The force component F2 _{y in the} direction and the force component F2 _{α in} the anti-squart angle α direction are decomposed. When the motor is driven, a rear dive in which the rear portion of the vehicle sinks is generated by the force component F2 _{y in the} vehicle vertical direction.

  By the way, as described above, the reaction force against the driving force of the motor 3 is received by the torque rod 9 via the motor housing 3a and transmitted from the torque rod 9 to the vehicle body side member. In this case, the reaction force against the driving force of the motor 3 is transmitted to the vehicle body side member without passing through the suspensions 13, 15, 17, 19.

  On the other hand, the reaction force against the braking force of the brake caliper 5d is received by the upper arm 15 and the lower arm 13 through the carrier 5a. Further, the braking force transmitted to the lower arm 13 is transmitted to the vehicle main body side member via the shock absorber 17 and the coil spring 19.

  Thus, the driving force of the motor 3 during vehicle acceleration and the braking force of the brake caliper 5d during vehicle braking differ in how these forces are received. Therefore, the vehicle vertical force applied to the suspensions 13, 15, 17, and 19 can be set separately during vehicle acceleration and vehicle braking. In other words, the anti-squart angle α and the anti-lift angle β can be set separately, and the pitching postures during vehicle acceleration and vehicle braking can be set individually.

  As described above, in the wheel device 1 according to the present embodiment, the motor housing 3 a and the vehicle main body side member are connected via the torque rod 9. Thus, the reaction force against the braking force of the brake caliper 5d is received by the upper arm 15 and the lower arm 13 through the carrier 5a. Further, the braking force transmitted to the lower arm 13 is transmitted to the vehicle main body side member via the shock absorber 17 and the coil spring 19. Thereby, the anti-squat angle α and the anti-lift angle β can be set individually. For example, while optimally setting the pitch attitude during vehicle acceleration based on the anti-squart angle α, independently of this setting, the pitch attitude during vehicle braking is optimally set based on the anti-lift angle β. be able to. That is, the vehicle posture can be set easily and optimally.

  In the prior art, the reaction force against the driving torque of the motor 100 and the reaction force against the braking force of the brake caliper are transmitted to the upper arm 101 and the lower arm 103 via the carrier, and are transmitted to the vehicle main body side member. Therefore, the above-described anti-squart angle and anti-lift angle are the same angle θ (FIG. 4). In this case, the anti-squart angle θ and the anti-lift angle θ are set simultaneously. Therefore, the setting of the pitch posture at the time of vehicle acceleration and the setting of the pitch posture at the time of vehicle braking may interfere with each other and be subject to design restrictions. That is, the wheel device 1 according to this embodiment described above can set the vehicle posture more optimally as compared with the prior art.

  As mentioned above, although the best mode for carrying out the present invention has been described using one embodiment, the present invention is not limited to such one embodiment, and within the scope not departing from the gist of the present invention, Various modifications and substitutions can be made to the above-described embodiment.

  For example, the double wishbone type suspension is applied to the above-described embodiment, but it can also be applied to a strut type suspension (McPherson type). It can also be applied to a multi-link double wishbone suspension.

  Moreover, in the said one Example, although applied to the rear wheel (non-steering wheel) 7 of a vehicle, it is applicable also to the front wheel (steering wheel) of a vehicle.

  Further, in the above embodiment, the torque rod 9 extends in the vehicle front-rear direction, one end is connected to the lower end portion 3e of the motor housing 3a, and the other end is connected to the vehicle body side member. You may be connected with the upper end part or side part of the housing 3a. That is, if the reaction force generated when the motor 3 is driven or braked can be transmitted to the vehicle main body side member via the motor housing 3a and the torque rod 9, the torque rod 9 can be attached at an arbitrary position. .

  In the above embodiment, one end of the shock absorber 17 is connected to the lower arm 13 via a bush, but one end of the shock absorber 17 may be connected to the upper arm 15 or the carrier 5a via a bush.

  When one end of the shock absorber 17 is connected to the upper arm 15, the reaction force against the braking force of the brake caliper 5 d is transmitted to the shock absorber 17 and the coil spring 19 via the carrier 5 a and the upper arm 15. When one end of the shock absorber 17 is connected to the carrier 5a, a reaction force against the braking force of the brake caliper 5d is transmitted to the shock absorber 17 and the coil spring 19 through the carrier 5a.

  In the above embodiment, the anti-squart angle α and the anti-lift angle β of the vehicle rear (rear part of the vehicle) are set to be different, but the anti-lift angle and the anti-dive angle of the vehicle front (front part of the vehicle) are It may be set differently. Note that the anti-squart angle α at the rear of the vehicle and the anti-lift angle at the front of the vehicle have a certain correlation. Further, the anti-lift angle β at the rear of the vehicle and the anti-dive angle at the front of the vehicle have a certain correlation.

  The present invention can be used for a wheel device. The appearance, weight, size, running performance, etc. of the vehicle to be mounted are not limited.

1 is a schematic cross-sectional view of a wheel device according to an embodiment of the present invention, showing a state where the wheel device is mounted on a left rear wheel. It is a figure which shows the anti-squat angle | corner (alpha) and the anti-lift angle (beta) in the wheel apparatus which concerns on one Example of this invention. It is a figure which shows the relationship between the braking force F1 of a brake caliper, anti-lift angle (beta), and the driving force F2 of a motor, and anti-squart angle (alpha). It is a figure which shows the anti-squart angle | corner (alpha) and antilift angle (beta) in a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wheel apparatus 3 Motor 3a Motor housing 5 Wheel support member 5a Carrier 5d Brake caliper 7 Wheel 9 Torque rod (arm member)
11 Disc rotor 13 Lower arm 15 Upper arm 17 Shock absorber 19 Coil spring

Claims (4)

A motor disposed on the wheel for rotationally driving or regeneratively braking the wheel;
A wheel support member connected to the vehicle body via a suspension and rotatably supporting the wheel;
A brake device disposed on the wheel support member and configured to frictionally brake the wheel,
A wheel device comprising: an arm member having one end connected to the vehicle body and the other end connected to a housing of the motor. The wheel device according to claim 1,
The wheel device according to claim 1, wherein the arm member transmits a reaction force generated by the rotational driving or the regenerative braking of the motor to the vehicle body. The wheel device according to claim 1 or 2,
The wheel device is characterized in that the arm member is disposed so that an anti-squat angle α that determines a pitching posture during vehicle acceleration is different from an anti-lift angle β that determines a pitching posture during vehicle braking. The wheel device according to any one of claims 1 to 3,
The wheel device, wherein the arm member extends in a vehicle front-rear direction.

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