CN111114621A

CN111114621A - Steering system for hub-driven vehicle and hub-driven vehicle

Info

Publication number: CN111114621A
Application number: CN201811278543.4A
Authority: CN
Inventors: 牟伟丰; 陈映杰; 李文杰; 楚向锋
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2018-10-30
Filing date: 2018-10-30
Publication date: 2020-05-08

Abstract

The invention relates to a steering system for a hub-driven vehicle and the hub-driven vehicle. The steering system comprises a steering knuckle connected with a wheel of a wheel hub driven vehicle in a torsion-proof manner and a driving motor, wherein the driving motor drives the steering knuckle to drive the corresponding wheel to steer, a stator of the driving motor is coaxially fixed on a guide rod of a suspension of the wheel hub driven vehicle, a rotor of the driving motor is rotatably supported on the guide rod, and the rotor is connected with the steering knuckle in the torsion-proof manner. The steering system avoids the limitation of the steering transverse pull rod on the steering angle of the wheels, and has simple structure, flexible steering and high steering precision.

Description

Steering system for hub-driven vehicle and hub-driven vehicle

Technical Field

The invention relates to the field of hub-driven vehicles. In particular, the present invention relates to a steering system for a hub driven vehicle and a hub driven vehicle including the steering system.

Background

Conventional vehicles use half shafts to transmit torque generated by an electric motor to wheels to drive the wheels to rotate, while tie rods are provided to steer the wheels. The half-shafts and tie rods limit the movement space of the wheels when they are steered, so that the steering angle that the wheels can achieve is very small, and therefore the conventional vehicle requires a large turning radius when it is steered (turning radius is usually larger than 4m for most of the conventional vehicles, and turning radius of about 3m can be obtained for only a few conceptual vehicle types). Such a large turning radius makes it difficult for conventional vehicles to evade under complicated road conditions. In some situations, such as when an edge stop is desired, it is difficult to conveniently stop using conventional vehicle steering systems.

New energy automobiles become a main direction of future development of the automobile industry, the driving technology of new energy automobiles is greatly different from the driving technology of internal combustion engine automobiles, and one type of driving technology has good development prospect, namely the hub motor technology. The wheel hub motor technology is also called as the wheel built-in motor technology, and the most important characteristic is that the power, transmission and braking devices are integrated into the contour, so that the mechanical part of the electric vehicle is greatly simplified. The vehicle driven by the wheel hub motor does not need to be provided with a half shaft any more, the angle of the wheel capable of rotating is larger when the vehicle turns, and the steering performance is better.

CN 105437951 a discloses a hub driving device that drives wheels to rotate by an in-wheel motor and steers the wheels by tie rods and knuckles. Although half shafts are no longer required in such hub-driven vehicles, it is still necessary to provide tie rods, or the like, to drive the wheels to steer in cooperation with the knuckles by means of a linkage mechanism such as a tie rod. The angle through which the tie rods can turn the wheels is limited, thereby limiting further improvements in the flexibility of the wheel steering system.

Disclosure of Invention

Therefore, the technical problem to be solved by the invention is to provide a vehicle steering system which is simple in structure, flexible in steering and high in steering precision.

The above problem is solved by a steering system for a hub driven vehicle according to the present invention. The steering system comprises a steering knuckle connected with a wheel of a wheel hub driven vehicle in a torsion-proof manner and a driving motor, wherein the driving motor drives the steering knuckle to drive the corresponding wheel to steer, a stator of the driving motor is coaxially fixed on a guide rod of a suspension of the wheel hub driven vehicle, a rotor of the driving motor is rotatably supported on the guide rod, and the rotor is connected with the steering knuckle in the torsion-proof manner. Because the steering of every wheel is driven by solitary motor, therefore no longer need connect the tie rod of turning between different wheels and transmit the power of turning, the restriction that single wheel received around the rotation of guide bar reduces greatly, so just can turn to with bigger angle, and then improved a steering system's flexibility, simultaneously, the motor is coaxial to be arranged on the guide bar, has saved overall arrangement space greatly. Preferably, the driving motor is an outer rotor type motor. The guide rod penetrates through the center of the driving motor and is connected with the stator in a torsion-resistant mode, the stator is static relative to the guide rod, and the rotor is sleeved on the outer side of the stator and can rotate relative to the guide rod.

According to a preferred embodiment of the invention, the steering knuckle is arranged coaxially outside the drive motor. The knuckle sleeve is established in the motor outside to be connected with driving motor's rotor antitorque, the rotor directly drives the knuckle and rotates, can realize the accurate control to steering angle, and the knuckle plays motor casing's effect simultaneously, can protect the motor and shield electromagnetic interference. Preferably, the steering knuckle is supported on the guide rod by a bearing. The knuckle is rotatable relative to the guide bar by means of a bearing.

According to a further preferred embodiment of the invention, the rotor is connected in a rotationally fixed manner to a housing of the drive motor, and the steering knuckle is formed integrally with the housing of the drive motor. The housing provides protection and electromagnetic shielding for the drive motor and transmits the rotational movement of the rotor to the knuckle, thereby driving the wheel to steer through the knuckle. Preferably, the housing is supported on the guide bar by bearings. The housing is rotatable relative to the guide bar by means of bearings.

According to another preferred embodiment of the invention, the steering system further comprises a sealing means, which is arranged outside the bearing. The sealing device can prevent external dust from entering the motor, thereby protecting the normal operation of the motor.

According to another preferred embodiment of the present invention, the steering system further comprises an electronic control unit connected to the driving motor and receiving a control request of a driver to control the operation of the driving motor, thereby achieving the driver's control of the steering of the wheels. Since according to the invention a drive motor is provided for each steering knuckle separately, i.e. each wheel has a separate steering system, the electronic control unit can be connected to the respective steering system and coordinate the steering movements of the respective steering system when steering takes place.

The above technical problem is also solved by a hub driven vehicle according to the present invention, which comprises a steering system having the above features.

Drawings

The invention is further described below with reference to the accompanying drawings. Identical reference numbers in the figures denote functionally identical elements. Wherein:

fig. 1 is a schematic sectional view of a steering system according to an embodiment of the present invention.

Detailed Description

Fig. 1 is a schematic sectional view of a steering system 1 according to an embodiment of the present invention. As shown in fig. 1, the steering system 1 includes a knuckle 4 and a drive motor 5. A hub drive system (not shown) is mounted in the wheel 2, and the hub of the wheel 2 is connected in a rotationally fixed manner to the knuckle 4. The suspension system of the vehicle comprises a guide bar 3, which guide bar 3 is connected to other parts of the chassis or body (not shown) via an upper arm 10 and a lower arm 11 etc. The guide rod 3 passes through the knuckle 4 and is supported on the knuckle 4 by means of two bearings 9. The steering system 1 may have one or more bearings 9 (2 shown in the figure). A driving motor 5 is installed in the knuckle 4, and the driving motor 5 is an outer rotor type motor having a stator 7 and a rotor 8. The stator 7 is coaxially fixed on the guide rod 3, and the rotor 8 is coaxially sleeved outside the stator 7 and fixed on the motor shell. The motor housing is fixed inside the knuckle 4 and is preferably formed integrally with the knuckle 4. Alternatively, the knuckle 4 may directly serve as a housing for fixing and enclosing the driving motor 5 without providing a separate housing.

When the vehicle turns, the driving motor 5 runs, the rotor 8 rotates relative to the stator 7, the steering knuckle 4 is driven to rotate relative to the guide rod 3, the wheel 2 rotates relative to the guide rod 3, and finally the steering of the wheel is achieved.

The steering system 1 according to the embodiment can provide a separate steering driving motor 5 for each of the steerable wheels 2, and thus, there is no need to provide tie rods to transmit steering torque from a single source to different wheels, so that the limitation of the tie rods to the steering angle of the wheels is avoided, and the flexibility of wheel steering is greatly improved. In addition, because the steering drive motor 5 is integrated in the knuckle 4, the construction is simple, and the installation space is greatly saved. In addition, as the rotor 8 is directly connected with the steering knuckle 4 in a torque-resistant manner, accurate transmission between the driving motor 5 and the steering knuckle 4 can be realized, and the steering angle of the wheel 2 can be accurately controlled. The steering system 1 of the invention can control the wheels to accurately steer within a range of +/-90 degrees.

In an embodiment of the invention, the steering system 1 is further provided with an electronic control unit 6 connected to the drive motor 5. The electronic control unit 6 receives a control instruction of a driver, and sends a control signal to the driving motor 5 according to the control instruction to control the operation of the driving motor 5, so as to control the different wheels 2 to cooperatively steer.

Furthermore, in an embodiment of the present invention, the steering system 1 may further include a sealing device (not shown). Sealing device sets up in the outside of every bearing, prevents that external dust from entering into driving motor 5 in, and then ensures driving motor 5's normal operating.

Although possible embodiments have been described by way of example in the above description, it should be understood that numerous embodiment variations exist, still by way of combination of all technical features and embodiments that are known and that are obvious to a person skilled in the art. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. From the foregoing description, one of ordinary skill in the art will more particularly provide a technical guide to convert at least one exemplary embodiment, wherein various changes may be made, particularly in matters of function and structure of the components described, without departing from the scope of the following claims.

Reference numerals

1 steering system

2 wheel

3 guide rod

4 steering knuckle

5 drive motor

6 electronic control unit

7 stator

8 rotor

9 bearing

10 Upper arm

11 lower arm

Claims

1. A steering system (1) for a wheel hub driven vehicle comprises a steering knuckle (4) and a driving motor (5), wherein the steering knuckle (4) is connected with a wheel (2) of the wheel hub driven vehicle in a torsion-proof manner, the driving motor (5) drives the steering knuckle (4) to drive the corresponding wheel (2) to steer,

it is characterized in that the preparation method is characterized in that,

the stator (7) of the drive motor (5) is coaxially fixed to a guide rod (3) of a suspension of the wheel hub drive vehicle, the rotor (8) of the drive motor (5) is rotatably mounted on the guide rod (3), and the rotor (8) is connected in a rotationally fixed manner to the steering knuckle (4).

2. Steering system (1) according to claim 1, characterized in that the steering knuckle (4) is arranged coaxially outside the drive motor (5).

3. Steering system (1) according to claim 2, characterized in that the steering knuckle (4) is supported on the guide bar (3) by means of a bearing (9).

4. Steering system (1) according to claim 1, characterized in that the rotor (8) is non-rotatably connected with the housing of the drive motor (5) and the steering knuckle (4) is formed integrally with the housing of the drive motor (5).

5. Steering system (1) according to claim 4, characterized in that the housing is supported on the guide rod (3) by means of a bearing (9).

6. Steering system (1) according to claim 1, characterized in that said drive motor (5) is an outer rotor motor.

7. Steering system (1) according to claim 3 or 5, characterized in that the steering system (1) further comprises sealing means, which are arranged outside the bearing (9).

8. Steering system (1) according to claim 1, characterized in that the steering system (1) further comprises an electronic control unit (6), which electronic control unit (6) is connected with the drive motor (5) and controls the operation of the drive motor (5).

9. A hub driven vehicle comprising a steering system (1) according to any one of claims 1-8.