阅读说明：本技术 轮毂电机分布式电驱动汽车多模式转向机构及其方法 (Multi-mode steering mechanism and method for wheel hub motor distributed electric drive automobile ) 是由 提艳 宋廷伦 崔晓迪 李涛 储亚峰 李立君 于 2019-09-25 设计创作，主要内容包括：本发明公开了一种轮毂电机分布式电驱动汽车多模式转向机构及其方法,转向机构包含转向操纵模块、前转向模块、后转向模块、车速传感器、行驶模式切换模块和控制模块；控制模块分别和车速传感器、行驶模式切换模块、前转向模块、后转向模块相连,用于根据车速传感器、行驶模式切换模块的数据控制前转向模块、后转向模块工作,使得汽车能够工作在四种模式：两前轮转向模式、四轮转向模式、定点零半径转向模式、横向行驶模式。(The invention discloses a multi-mode steering mechanism of an electric drive automobile with a distributed wheel hub motor and a method thereof, wherein the steering mechanism comprises a steering control module, a front steering module, a rear steering module, a vehicle speed sensor, a running mode switching module and a control module; the control module is respectively connected with the vehicle speed sensor, the driving mode switching module, the front steering module and the rear steering module and is used for controlling the front steering module and the rear steering module to work according to the data of the vehicle speed sensor and the driving mode switching module, so that the automobile can work in four modes: two front wheel steering mode, four wheel steering mode, fixed point zero radius steering mode, lateral driving mode.)

1. A multi-mode steering mechanism of an electrically driven automobile with a distributed wheel hub motor is characterized by comprising a steering control module, a front steering module, a rear steering module, a vehicle speed sensor, a running mode switching module and a control module;

the steering control module comprises a steering wheel, a steering column, a steering intermediate shaft, a steering shaft, a driving bevel gear, first to sixth driven bevel gears and first to second transmission bevel gears;

one end of the steering column is vertically and fixedly connected with the center of the steering wheel, and the other end of the steering column is connected with one end of the steering intermediate shaft through a universal joint; the other end of the steering intermediate shaft is connected with one end of the steering shaft through a universal joint; the other end of the steering shaft is coaxially and fixedly connected with a rotating shaft of the driving bevel gear;

the first driven bevel gear and the second driven bevel gear are respectively arranged on the left side and the right side of the driving bevel gear and are meshed with the driving bevel gear, and rotating shafts of the first driven bevel gear and the second driven bevel gear are perpendicular to the steering shaft; the rotating shafts of the first transmission bevel gear and the second transmission bevel gear are correspondingly and coaxially fixedly connected with the rotating shafts of the first driven bevel gear and the second driven bevel gear respectively; the third driven bevel gear and the fifth driven bevel gear are respectively arranged on two sides of the first transmission bevel gear and are meshed with the first transmission bevel gear, and rotating shafts of the third driven bevel gear and the fifth driven bevel gear are perpendicular to the rotating shaft of the first transmission bevel gear; the fourth driven bevel gear and the sixth driven bevel gear are respectively arranged on two sides of the first transmission bevel gear and are meshed with the second transmission bevel gear, and rotating shafts of the fourth driven bevel gear and the sixth driven bevel gear are perpendicular to a rotating shaft of the second transmission bevel gear;

the front steering module comprises a first wheel hub motor, a second wheel hub motor, a first front straight gear, a second front straight gear, a first front meshing gear ring, a second front meshing gear ring, a first front steering gear, a second front steering gear, a first steering rack, a second steering rack, a front left conduction unit and a front right conduction unit;

the first wheel hub motor, the second wheel hub motor, the third wheel hub motor, the fourth wheel hub motor, the fifth wheel hub motor, the sixth wheel hub;

the first steering rack and the second steering rack are respectively arranged on the frames at the inner sides of the left front wheel and the right front wheel of the automobile and are both vertical to the steering shaft;

the first front straight gear is meshed with the second front straight gear, and a rotating shaft of the first front straight gear is connected with the first front steering gear through a first front meshing gear ring; one end of the second front straight gear rotating shaft is connected with the rotating shaft of the second front steering gear through the second front meshing gear ring, and the other end of the second front straight gear rotating shaft is coaxially connected with the rotating shaft of the third driven bevel gear; the first front steering gear and the second front steering gear are meshed with the first steering rack, and the first front steering gear and the second front steering gear are not meshed with each other; a rotating shaft of the third front steering gear is coaxially and fixedly connected with a rotating shaft of the fourth driven bevel gear, and the third front steering gear is meshed with the first steering rack;

the output ends of the first steering rack and the second steering rack are respectively connected with the first hub motor and the second hub motor through the front left conduction unit and the front right conduction unit; the front left conducting unit and the front right conducting unit are respectively used for transmitting the steering torque of the steering wheel to the left front wheel and the right front wheel of the automobile;

the rear steering module comprises third to fourth hub motors, first to fourth rear straight gears, first to fourth rear meshing gear rings, first to fourth rear steering gears, third to fourth steering racks, a rear left conduction unit and a rear right conduction unit;

the third hub motor and the fourth hub motor are arranged at the left rear wheel and the right rear wheel of the automobile, and the rotors are fixedly connected with rims of the left rear wheel and the right rear wheel of the automobile respectively and are used for driving the left rear wheel and the right rear wheel of the automobile to rotate respectively;

the first rear straight gear is meshed with the second rear front straight gear, and a rotating shaft of the first rear straight gear is connected with a rotating shaft of the first rear steering gear through a first rear meshing gear ring; one end of the second rear straight gear rotating shaft is connected with the rotating shaft of the second rear steering gear through the second rear meshing gear ring, and the other end of the second rear straight gear rotating shaft is coaxially connected with the rotating shaft of the fifth driven bevel gear; the first rear steering gear and the second rear steering gear are meshed with the third steering rack, and the first rear steering gear and the second rear steering gear are not meshed with each other;

the third rear straight gear is meshed with the fourth rear front straight gear, one end of a rotating shaft of the third rear straight gear is connected with the rotating shaft of the third rear steering gear through a third rear meshed gear ring, and the other end of the rotating shaft of the third rear straight gear is coaxially connected with a rotating shaft of the sixth driven bevel gear; the fourth rear straight gear rotating shaft is connected with the rotating shaft of the fourth rear steering gear through the fourth rear meshing gear ring; the third rear steering gear and the fourth rear steering gear are meshed with the fourth steering rack, and the third rear steering gear and the fourth rear steering gear are not meshed with each other;

the third steering rack and the fourth steering rack are respectively arranged on the frames at the inner sides of the left rear wheel and the right rear wheel of the automobile and are both vertical to the steering shaft; the output ends of the third steering rack and the fourth steering rack are respectively connected with the left rear wheel and the right rear wheel of the automobile through a rear left conduction unit and a rear right conduction unit;

the vehicle speed sensor is used for acquiring the vehicle speed of the vehicle and transmitting the vehicle speed to the control module;

the driving mode switching module is used for sending a driving mode selected by a user to the control module, and the driving mode comprises four modes: a two-front-wheel steering mode, a four-wheel steering mode, a fixed-point zero-radius steering mode and a transverse driving mode;

the control module is respectively and electrically connected with the vehicle speed sensor, the running mode switching module, the first to fourth hub motors, the first to second front meshing gear rings and the first to fourth rear meshing gear rings and is used for controlling the first to fourth hub motors, the first to second front meshing gear rings and the first to fourth rear meshing gear rings to work according to data of the vehicle speed sensor and the running mode switching module.

2. The multi-mode steering mechanism of the in-wheel motor distributed electric drive automobile according to claim 1, wherein the front left conducting unit, the front right conducting unit, the rear left conducting unit and the rear right conducting unit respectively comprise a steering tie rod, a steering knuckle and a control arm, wherein one end of the control arm is connected with the automobile frame through a ball pin, and the other end of the control arm is connected with the steering knuckle; one end of the steering tie rod is connected with the steering knuckle;

the steering knuckles of the front left conducting unit, the front right conducting unit, the rear left conducting unit and the rear right conducting unit are fixedly connected with the centers of the stators of the first to fourth hub motors respectively; the other ends of the tie rods of the front left conducting unit, the front right conducting unit, the rear left conducting unit and the rear right conducting unit are respectively connected with the output ends of the first steering rack, the second steering rack, the third steering rack and the fourth steering rack.

3. The two-front-wheel steering method of the multi-mode steering mechanism of the in-wheel motor distributed electrically-driven automobile based on the claim 1 is characterized by comprising the following specific steps of:

step A.1), a driver selects two front wheel steering modes through a driving mode switching module, and the driving mode switching module transmits the information to a control module;

step A.2), the control module controls the first rear meshing gear ring, the second rear meshing gear ring, the third rear meshing gear ring, the fourth rear meshing gear ring and the fourth rear meshing gear ring to be in a separated state, and controls the first front meshing gear ring, the second front meshing gear ring and the second front meshing gear ring to be in a meshed state;

step A.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to a first driven bevel gear and a second driven bevel gear through a steering column, a steering intermediate shaft, a steering shaft and a driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear and the second front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively.

4. The four-wheel steering method of the multi-mode steering mechanism of the in-wheel motor distributed electric drive automobile based on the claim 1 is characterized by comprising the following specific steps of:

b.1), the driver selects a four-wheel steering mode through a driving mode switching module, and the driving mode switching module transmits the information to a control module;

step B.2), the control module controls the first rear meshing gear ring, the second rear meshing gear ring, the third rear meshing gear ring, the fourth rear meshing gear ring and the fourth rear meshing gear ring to be in a separated state, and controls the first front meshing gear ring, the second front meshing gear ring and the second front meshing gear ring to be in a meshed state;

step B.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to a first driven bevel gear and a second driven bevel gear through a steering column, a steering intermediate shaft, a steering shaft and a driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear and the second front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively;

b.4), the control module receives the speed sensor to obtain the speed of the automobile;

step B.5), the module controls the vehicle speed to be compared with a preset first speed threshold value;

step B.5.1), when the vehicle speed is less than a preset speed threshold value, the control module controls the second rear meshing gear ring and the third rear meshing gear ring to be in a separated state, and controls the first rear meshing gear ring and the fourth rear meshing gear ring to be in a meshing state; the first driven bevel gear drives a third steering rack to move sequentially through a fifth driven bevel gear, a second rear straight gear, a first rear straight gear and a first rear steering gear; the second driven bevel gear drives a fourth steering rack to move sequentially through a sixth driven bevel gear, a third rear straight gear, a fourth rear straight gear and a fourth rear steering gear, so that the steering directions of a left rear wheel and a right rear wheel are opposite to the steering directions of a left front wheel and a right front wheel, and the ratio of the wheel rotation angle of the left rear wheel and the right rear wheel to the wheel rotation angle of the left front wheel and the right front wheel is a preset first proportional threshold;

step B.5.2), when the vehicle speed is greater than a preset speed threshold value, the control module controls the first rear meshing gear ring and the fourth rear meshing gear ring to be in a separated state, and controls the second rear meshing gear ring and the third rear meshing gear ring to be in a meshing state; the first driven bevel gear drives a third steering rack to move sequentially through a fifth driven bevel gear, a second rear straight gear and a second rear steering gear; the second driven bevel gear drives the fourth steering rack to move sequentially through the sixth driven bevel gear, the third rear straight gear and the third rear steering gear, so that the steering directions of the left rear wheel, the right rear wheel and the left front wheel and the right front wheel are the same, and the ratio of the wheel rotation angle of the left rear wheel and the right rear wheel to the wheel rotation angle of the left front wheel and the wheel rotation angle of the right front wheel is a preset second proportional threshold.

5. The fixed-point zero-radius steering method of the multi-mode steering mechanism of the in-wheel motor distributed electric-driven automobile based on the claim 1 is characterized by comprising the following specific steps of:

step C.1), a driver selects a fixed-point zero-radius steering mode through a driving mode switching module, and the driving mode switching module transmits the information to a control module;

step C.2), the control module controls the first front meshing gear ring to be in a meshing state, controls the second front meshing gear ring to be in a separating state and cuts off a power source of the second front steering gear;

step C.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to the first driven bevel gear and the second driven bevel gear through the steering column, the steering intermediate shaft, the steering shaft and the driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear, the first front straight gear and the first front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively, so that the turning angles arctan (L/d) of the left front wheel and the right front wheel are enabled, L represents the automobile wheelbase, d represents the wheelbase, and the steering of the two front wheels is completed;

step C.4), the control module controls the first rear meshing gear ring and the third rear meshing gear ring to be in a separated state, and controls the second rear meshing gear ring and the fourth rear meshing gear ring to be in a meshed state; the first driven bevel gear drives a third steering rack to move sequentially through a first transmission bevel gear, a fifth driven bevel gear, a second rear straight gear and a second rear steering gear; the second driven bevel gear drives a fourth steering rack to move sequentially through a second transmission bevel gear, a sixth driven bevel gear, a third rear straight gear, a fourth rear straight gear and a fourth rear steering gear; the third steering rack and the fourth steering rack transmit the steering torque of the steering wheel to the left rear wheel and the right rear wheel through the rear left transmission unit and the rear right transmission unit respectively, so that the turning angles of the left rear wheel and the right rear wheel of the automobile are arctan (L/d).

6. The transverse driving method of the multi-mode steering mechanism of the in-wheel motor distributed electric drive automobile based on the claim 1 is characterized by comprising the following specific steps of:

step D.1), the driver selects a transverse driving mode through the driving mode switching module, and the driving mode switching module transmits the information to the control module;

d.2), the control module controls the first front meshing gear ring to be in a meshing state and controls the second front meshing gear ring to be in a separating state, and a power source of the second front steering gear is cut off;

step D.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to a first driven bevel gear and a second driven bevel gear through a steering column, a steering intermediate shaft, a steering shaft and a driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear, the first front straight gear and the first front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively, so that the turning angles of the left front wheel and the right front wheel are 90 degrees, and the steering of the two front wheels is completed;

d.4), the control module controls the first rear meshing gear ring and the third rear meshing gear ring to be in a separated state, and controls the second rear meshing gear ring and the fourth rear meshing gear ring to be in a meshed state; the first driven bevel gear drives a third steering rack to move sequentially through a first transmission bevel gear, a fifth driven bevel gear, a second rear straight gear and a second rear steering gear; the second driven bevel gear drives a fourth steering rack to move sequentially through a second transmission bevel gear, a sixth driven bevel gear, a third rear straight gear, a fourth rear straight gear and a fourth rear steering gear; the third steering rack and the fourth steering rack transmit the steering torque of the steering wheel to the left rear wheel and the right rear wheel through the rear left transmission unit and the rear right transmission unit respectively, so that the rotation angles of the left rear wheel and the right rear wheel of the automobile are 90 degrees.

Technical Field

The invention relates to the technical field of wheel hub motor distributed electric drive automobiles, in particular to a wheel hub motor distributed electric drive automobile multi-mode steering mechanism and a method thereof.

Background

New energy automobiles become the main direction of automobile industry development in various countries, and are also the research hotspots of various automobile enterprises and colleges. Among them, in the electric automobile field, the wheel hub motor distributed electric drive automobile has great development potential, and satisfies the national plan for developing new energy automobiles for a long time. Meanwhile, with the continuous increase of the automobile holding capacity, the problems of traffic congestion, lack of parking spaces and the like are seriously troubled. Because the transverse stabilizer bar of the traditional automobile steering system exists, the steering angle of the front wheel is limited to-35 degrees to +35 degrees, the steering flexibility is poor, and the automobile can turn around to run, enter and exit a garage, park and the like, so that a large space is needed, and energy waste is also caused.

Disclosure of Invention

The invention aims to solve the technical problem of overcoming the defects in the prior automobile steering system technology, and provides a multi-mode steering mechanism of an electric drive automobile with a distributed hub motor and a method thereof, which can realize the steering of two front wheels and the steering of four wheels; when four-wheel steering is carried out, not only can conventional steering be realized, but also zero-radius steering and transverse driving can be realized in a narrow space range.

The invention adopts the following technical scheme for solving the technical problems:

a multi-mode steering mechanism of an electric drive automobile with a distributed wheel hub motor comprises a steering control module, a front steering module, a rear steering module, a vehicle speed sensor, a running mode switching module and a control module;

the steering control module comprises a steering wheel, a steering column, a steering intermediate shaft, a steering shaft, a driving bevel gear, first to sixth driven bevel gears and first to second transmission bevel gears;

one end of the steering column is vertically and fixedly connected with the center of the steering wheel, and the other end of the steering column is connected with one end of the steering intermediate shaft through a universal joint; the other end of the steering intermediate shaft is connected with one end of the steering shaft through a universal joint; the other end of the steering shaft is coaxially and fixedly connected with a rotating shaft of the driving bevel gear;

the first driven bevel gear and the second driven bevel gear are respectively arranged on the left side and the right side of the driving bevel gear and are meshed with the driving bevel gear, and rotating shafts of the first driven bevel gear and the second driven bevel gear are perpendicular to the steering shaft; the rotating shafts of the first transmission bevel gear and the second transmission bevel gear are correspondingly and coaxially fixedly connected with the rotating shafts of the first driven bevel gear and the second driven bevel gear respectively; the third driven bevel gear and the fifth driven bevel gear are respectively arranged on two sides of the first transmission bevel gear and are meshed with the first transmission bevel gear, and rotating shafts of the third driven bevel gear and the fifth driven bevel gear are perpendicular to the rotating shaft of the first transmission bevel gear; the fourth driven bevel gear and the sixth driven bevel gear are respectively arranged on two sides of the first transmission bevel gear and are meshed with the second transmission bevel gear, and rotating shafts of the fourth driven bevel gear and the sixth driven bevel gear are perpendicular to a rotating shaft of the second transmission bevel gear;

the front steering module comprises a first wheel hub motor, a second wheel hub motor, a first front straight gear, a second front straight gear, a first front meshing gear ring, a second front meshing gear ring, a first front steering gear, a second front steering gear, a first steering rack, a second steering rack, a front left conduction unit and a front right conduction unit;

the first wheel hub motor, the second wheel hub motor, the third wheel hub motor, the fourth wheel hub motor, the fifth wheel hub motor, the sixth wheel hub;

the first steering rack and the second steering rack are respectively arranged on the frames at the inner sides of the left front wheel and the right front wheel of the automobile and are both vertical to the steering shaft;

the first front straight gear is meshed with the second front straight gear, and a rotating shaft of the first front straight gear is connected with the first front steering gear through a first front meshing gear ring; one end of the second front straight gear rotating shaft is connected with the rotating shaft of the second front steering gear through the second front meshing gear ring, and the other end of the second front straight gear rotating shaft is coaxially connected with the rotating shaft of the third driven bevel gear; the first front steering gear and the second front steering gear are meshed with the first steering rack, and the first front steering gear and the second front steering gear are not meshed with each other; a rotating shaft of the third front steering gear is coaxially and fixedly connected with a rotating shaft of the fourth driven bevel gear, and the third front steering gear is meshed with the first steering rack;

the output ends of the first steering rack and the second steering rack are respectively connected with the first hub motor and the second hub motor through the front left conduction unit and the front right conduction unit; the front left conducting unit and the front right conducting unit are respectively used for transmitting the steering torque of the steering wheel to the left front wheel and the right front wheel of the automobile;

the rear steering module comprises third to fourth hub motors, first to fourth rear straight gears, first to fourth rear meshing gear rings, first to fourth rear steering gears, third to fourth steering racks, a rear left conduction unit and a rear right conduction unit;

the third hub motor and the fourth hub motor are arranged at the left rear wheel and the right rear wheel of the automobile, and the rotors are fixedly connected with rims of the left rear wheel and the right rear wheel of the automobile respectively and are used for driving the left rear wheel and the right rear wheel of the automobile to rotate respectively;

the first rear straight gear is meshed with the second rear front straight gear, and a rotating shaft of the first rear straight gear is connected with a rotating shaft of the first rear steering gear through a first rear meshing gear ring; one end of the second rear straight gear rotating shaft is connected with the rotating shaft of the second rear steering gear through the second rear meshing gear ring, and the other end of the second rear straight gear rotating shaft is coaxially connected with the rotating shaft of the fifth driven bevel gear; the first rear steering gear and the second rear steering gear are meshed with the third steering rack, and the first rear steering gear and the second rear steering gear are not meshed with each other;

the third rear straight gear is meshed with the fourth rear front straight gear, one end of a rotating shaft of the third rear straight gear is connected with the rotating shaft of the third rear steering gear through a third rear meshed gear ring, and the other end of the rotating shaft of the third rear straight gear is coaxially connected with a rotating shaft of the sixth driven bevel gear; the fourth rear straight gear rotating shaft is connected with the rotating shaft of the fourth rear steering gear through the fourth rear meshing gear ring; the third rear steering gear and the fourth rear steering gear are meshed with the fourth steering rack, and the third rear steering gear and the fourth rear steering gear are not meshed with each other;

the third steering rack and the fourth steering rack are respectively arranged on the frames at the inner sides of the left rear wheel and the right rear wheel of the automobile and are both vertical to the steering shaft; the output ends of the third steering rack and the fourth steering rack are respectively connected with the left rear wheel and the right rear wheel of the automobile through a rear left conduction unit and a rear right conduction unit;

the vehicle speed sensor is used for acquiring the vehicle speed of the vehicle and transmitting the vehicle speed to the control module;

the driving mode switching module is used for sending a driving mode selected by a user to the control module, and the driving mode comprises four modes: a two-front-wheel steering mode, a four-wheel steering mode, a fixed-point zero-radius steering mode and a transverse driving mode;

the control module is respectively and electrically connected with the vehicle speed sensor, the running mode switching module, the first to fourth hub motors, the first to second front meshing gear rings and the first to fourth rear meshing gear rings and is used for controlling the first to fourth hub motors, the first to second front meshing gear rings and the first to fourth rear meshing gear rings to work according to data of the vehicle speed sensor and the running mode switching module.

As a further optimization scheme of the multi-mode steering mechanism of the wheel hub motor distributed electric drive automobile, the front left conduction unit, the front right conduction unit, the rear left conduction unit and the rear right conduction unit respectively comprise a steering tie rod, a steering knuckle and a control arm, wherein one end of the control arm is connected with a frame through a ball pin, and the other end of the control arm is connected with the steering knuckle; one end of the steering tie rod is connected with the steering knuckle;

the steering knuckles of the front left conducting unit, the front right conducting unit, the rear left conducting unit and the rear right conducting unit are fixedly connected with the centers of the stators of the first to fourth hub motors respectively; the other ends of the tie rods of the front left conducting unit, the front right conducting unit, the rear left conducting unit and the rear right conducting unit are respectively connected with the output ends of the first steering rack, the second steering rack, the third steering rack and the fourth steering rack.

The invention also discloses a two-front-wheel steering method of the wheel hub motor distributed electrically-driven automobile multi-mode steering mechanism, which comprises the following specific steps:

step A.1), a driver selects two front wheel steering modes through a driving mode switching module, and the driving mode switching module transmits the information to a control module;

step A.2), the control module controls the first rear meshing gear ring, the second rear meshing gear ring, the third rear meshing gear ring, the fourth rear meshing gear ring and the fourth rear meshing gear ring to be in a separated state, and controls the first front meshing gear ring, the second front meshing gear ring and the second front meshing gear ring to be in a meshed state;

step A.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to a first driven bevel gear and a second driven bevel gear through a steering column, a steering intermediate shaft, a steering shaft and a driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear and the second front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively.

The invention also discloses a four-wheel steering method of the multi-mode steering mechanism of the hub motor distributed electric drive automobile, which comprises the following specific steps:

b.1), the driver selects a four-wheel steering mode through a driving mode switching module, and the driving mode switching module transmits the information to a control module;

step B.2), the control module controls the first rear meshing gear ring, the second rear meshing gear ring, the third rear meshing gear ring, the fourth rear meshing gear ring and the fourth rear meshing gear ring to be in a separated state, and controls the first front meshing gear ring, the second front meshing gear ring and the second front meshing gear ring to be in a meshed state;

step B.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to a first driven bevel gear and a second driven bevel gear through a steering column, a steering intermediate shaft, a steering shaft and a driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear and the second front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively;

b.4), the control module receives the speed sensor to obtain the speed of the automobile;

step B.5), the module controls the vehicle speed to be compared with a preset first speed threshold value;

step B.5.1), when the vehicle speed is less than a preset speed threshold value, the control module controls the second rear meshing gear ring and the third rear meshing gear ring to be in a separated state, and controls the first rear meshing gear ring and the fourth rear meshing gear ring to be in a meshing state; the first driven bevel gear drives a third steering rack to move sequentially through a fifth driven bevel gear, a second rear straight gear, a first rear straight gear and a first rear steering gear; the second driven bevel gear drives a fourth steering rack to move sequentially through a sixth driven bevel gear, a third rear straight gear, a fourth rear straight gear and a fourth rear steering gear, so that the steering directions of a left rear wheel and a right rear wheel are opposite to the steering directions of a left front wheel and a right front wheel, and the ratio of the wheel rotation angle of the left rear wheel and the right rear wheel to the wheel rotation angle of the left front wheel and the right front wheel is a preset first proportional threshold;

step B.5.2), when the vehicle speed is greater than a preset speed threshold value, the control module controls the first rear meshing gear ring and the fourth rear meshing gear ring to be in a separated state, and controls the second rear meshing gear ring and the third rear meshing gear ring to be in a meshing state; the first driven bevel gear drives a third steering rack to move sequentially through a fifth driven bevel gear, a second rear straight gear and a second rear steering gear; the second driven bevel gear drives the fourth steering rack to move sequentially through the sixth driven bevel gear, the third rear straight gear and the third rear steering gear, so that the steering directions of the left rear wheel, the right rear wheel and the left front wheel and the right front wheel are the same, and the ratio of the wheel rotation angle of the left rear wheel and the right rear wheel to the wheel rotation angle of the left front wheel and the wheel rotation angle of the right front wheel is a preset second proportional threshold.

The invention also discloses a fixed-point zero-radius steering method of the wheel hub motor distributed electrically-driven automobile multi-mode steering mechanism, which comprises the following specific steps:

step C.1), a driver selects a fixed-point zero-radius steering mode through a driving mode switching module, and the driving mode switching module transmits the information to a control module;

step C.2), the control module controls the first front meshing gear ring to be in a meshing state, controls the second front meshing gear ring to be in a separating state and cuts off a power source of the second front steering gear;

step C.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to the first driven bevel gear and the second driven bevel gear through the steering column, the steering intermediate shaft, the steering shaft and the driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear, the first front straight gear and the first front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively, so that the turning angles arctan (L/d) of the left front wheel and the right front wheel are enabled, L represents the automobile wheelbase, d represents the wheelbase, and the steering of the two front wheels is completed;

step C.4), the control module controls the first rear meshing gear ring and the third rear meshing gear ring to be in a separated state, and controls the second rear meshing gear ring and the fourth rear meshing gear ring to be in a meshed state; the first driven bevel gear drives a third steering rack to move sequentially through a first transmission bevel gear, a fifth driven bevel gear, a second rear straight gear and a second rear steering gear; the second driven bevel gear drives a fourth steering rack to move sequentially through a second transmission bevel gear, a sixth driven bevel gear, a third rear straight gear, a fourth rear straight gear and a fourth rear steering gear; the third steering rack and the fourth steering rack transmit the steering torque of the steering wheel to the left rear wheel and the right rear wheel through the rear left transmission unit and the rear right transmission unit respectively, so that the turning angles of the left rear wheel and the right rear wheel of the automobile are arctan (L/d).

The invention also discloses a transverse running method of the multi-mode steering mechanism of the wheel hub motor distributed electric drive automobile, which comprises the following specific steps:

step D.1), the driver selects a transverse driving mode through the driving mode switching module, and the driving mode switching module transmits the information to the control module;

d.2), the control module controls the first front meshing gear ring to be in a meshing state and controls the second front meshing gear ring to be in a separating state, and a power source of the second front steering gear is cut off;

step D.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to a first driven bevel gear and a second driven bevel gear through a steering column, a steering intermediate shaft, a steering shaft and a driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear, the first front straight gear and the first front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively, so that the turning angles of the left front wheel and the right front wheel are 90 degrees, and the steering of the two front wheels is completed;

d.4), the control module controls the first rear meshing gear ring and the third rear meshing gear ring to be in a separated state, and controls the second rear meshing gear ring and the fourth rear meshing gear ring to be in a meshed state; the first driven bevel gear drives a third steering rack to move sequentially through a first transmission bevel gear, a fifth driven bevel gear, a second rear straight gear and a second rear steering gear; the second driven bevel gear drives a fourth steering rack to move sequentially through a second transmission bevel gear, a sixth driven bevel gear, a third rear straight gear, a fourth rear straight gear and a fourth rear steering gear; the third steering rack and the fourth steering rack transmit the steering torque of the steering wheel to the left rear wheel and the right rear wheel through the rear left transmission unit and the rear right transmission unit respectively, so that the rotation angles of the left rear wheel and the right rear wheel of the automobile are 90 degrees.

Compared with the prior art, the invention adopting the technical scheme has the following technical effects:

the multi-mode steering mechanism capable of realizing the distributed electric drive automobile with the hub motor can realize steering of two front wheels and four-wheel steering; the four-wheel steering not only can realize the steering of the high-speed front wheel, the steering angle of the rear wheel, which is the same as the steering angle of the front wheel, and the steering of the steering angle of the rear wheel, which is opposite to the steering angle of the front wheel, in the normal driving process, but also can realize the fixed-point zero-radius steering and the transverse driving in a narrow space range.

Drawings

FIG. 1 is a schematic view of the entire vehicle structure of the present invention;

FIG. 2 is a schematic view of the construction of the steering module of the present invention;

FIG. 3 is a schematic view of the front wheel steering module and the steering module of the present invention showing the mating of parts;

FIG. 4 is a schematic view of the arrangement of the rear wheel steering module and the steering module of the present invention in combination;

FIG. 5 is a schematic illustration of a two front wheel steering mode of the present invention;

FIG. 6 is a schematic diagram of a four-wheel steering mode of the present invention with vehicle speed less than a preset first speed threshold;

FIG. 7 is a schematic diagram of a four-wheel steering mode of the present invention with vehicle speed greater than a preset first speed threshold;

FIG. 8 is a schematic diagram of the fixed point zero radius steering mode of the present invention;

fig. 9 is a schematic view of the lateral traveling mode in the present invention.

In the figure, 1-steering wheel, 2-steering column, 3-steering intermediate shaft, 4-universal joint, 5-steering shaft, 6-frame, 7-driving bevel gear, 8-first driven bevel gear, 9-second driven bevel gear, 10A-fifth driven bevel gear, 10B-sixth driven bevel gear, 11A-first driving bevel gear; 11B-a second drive bevel gear; 12A-a third driven bevel gear; 12B-a fourth driven bevel gear;

13-first front spur gear, 14-second front spur gear, 15A-first front meshing ring gear, 15B-second front meshing ring gear, 16A-first front steering gear, 16B-second front steering gear, 17A-first steering rack, 17B-second steering rack, 17C-third steering rack, 17D-fourth steering rack, 18A-rotating shaft of first driven bevel gear, 18B-rotating shaft of third driven bevel gear, 18C-rotating shaft of first front spur gear, 18D-rotating shaft of second driven bevel gear, 18E-rotating shaft of fourth driven bevel gear, 19A-rotating shaft of fifth driven bevel gear, 19B-rotating shaft of sixth driven bevel gear, 19C-rotating shaft of first rear spur gear, 19D-rotating shaft of fourth rear spur gear, 20A-a first rear spur gear, 20B-a second rear spur gear, 20C-a third rear spur gear, 20D-a fourth rear spur gear, 21A-a first rear meshing ring gear, 21B-a second rear meshing ring gear, 21C-a third rear meshing ring gear, 21D-a fourth rear meshing ring gear, 22A-a first rear steering gear, 22B-a second rear steering gear, 22C-a third rear steering gear, 22D-a fourth rear steering gear, 23-a front wheel, 24A-a knuckle of a front left conduction unit, 24B-a knuckle of a front right conduction unit, 24C-a knuckle of a rear left conduction unit, 24D-a knuckle of a rear right conduction unit, 25A-a control arm of a front left conduction unit, 25B-a control arm of a front right conduction unit, 25C-control arm of rear left conduction unit, 25D-control arm of rear right conduction unit, 26A-tie rod of front left conduction unit, 26B-tie rod of front right conduction unit, 26C-tie rod of rear left conduction unit, 26D-tie rod of rear right conduction unit, and 27-in-wheel motor.

Detailed Description

The technical scheme of the invention is further explained in detail by combining the attached drawings:

the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, components are exaggerated for clarity.

As shown in figure 1, the invention discloses a multi-mode steering mechanism of a wheel hub motor distributed electric drive automobile, which comprises a steering control module, a front steering module, a rear steering module, a vehicle speed sensor, a running mode switching module and a control module.

As shown in fig. 2, the steering module includes a steering wheel, a steering column, a steering intermediate shaft, a steering shaft, a driving bevel gear, first to sixth driven bevel gears, and first to second driving bevel gears;

one end of the steering column is vertically and fixedly connected with the center of the steering wheel, and the other end of the steering column is connected with one end of the steering intermediate shaft through a universal joint; the other end of the steering intermediate shaft is connected with one end of the steering shaft through a universal joint; the other end of the steering shaft is coaxially and fixedly connected with a rotating shaft of the driving bevel gear;

the first driven bevel gear and the second driven bevel gear are respectively arranged on the left side and the right side of the driving bevel gear and are meshed with the driving bevel gear, and rotating shafts of the first driven bevel gear and the second driven bevel gear are perpendicular to the steering shaft; the rotating shafts of the first transmission bevel gear and the second transmission bevel gear are correspondingly and coaxially fixedly connected with the rotating shafts of the first driven bevel gear and the second driven bevel gear respectively; the third driven bevel gear and the fifth driven bevel gear are respectively arranged on two sides of the first transmission bevel gear and are meshed with the first transmission bevel gear, and rotating shafts of the third driven bevel gear and the fifth driven bevel gear are perpendicular to the rotating shaft of the first transmission bevel gear; and the fourth driven bevel gear and the sixth driven bevel gear are respectively arranged on two sides of the first transmission bevel gear and are meshed with the second transmission bevel gear, and rotating shafts of the fourth driven bevel gear and the sixth driven bevel gear are perpendicular to the rotating shaft of the second transmission bevel gear.

As shown in fig. 3, the front steering module includes first to second hub motors, first to second front spur gears, first to second front meshing gear rings, first to third front steering gears, first to second steering racks, a front left conduction unit, and a front right conduction unit;

the first wheel hub motor, the second wheel hub motor, the third wheel hub motor, the fourth wheel hub motor, the fifth wheel hub motor, the sixth wheel hub;

the first steering rack and the second steering rack are respectively arranged on the frames at the inner sides of the left front wheel and the right front wheel of the automobile and are both vertical to the steering shaft;

the first front straight gear is meshed with the second front straight gear, and a rotating shaft of the first front straight gear is connected with the first front steering gear through a first front meshing gear ring; one end of the second front straight gear rotating shaft is connected with the rotating shaft of the second front steering gear through the second front meshing gear ring, and the other end of the second front straight gear rotating shaft is coaxially connected with the rotating shaft of the third driven bevel gear; the first front steering gear and the second front steering gear are meshed with the first steering rack, and the first front steering gear and the second front steering gear are not meshed with each other; a rotating shaft of the third front steering gear is coaxially and fixedly connected with a rotating shaft of the fourth driven bevel gear, and the third front steering gear is meshed with the first steering rack;

the output ends of the first steering rack and the second steering rack are respectively connected with the first hub motor and the second hub motor through the front left conduction unit and the front right conduction unit; the front left conducting unit and the front right conducting unit are respectively used for transmitting the steering torque of the steering wheel to the left front wheel and the right front wheel of the automobile.

As shown in fig. 4, the rear steering module includes third to fourth hub motors, first to fourth rear spur gears, first to fourth rear meshing ring gears, first to fourth rear steering gears, third to fourth steering racks, a rear left conduction unit, and a rear right conduction unit;

the third hub motor and the fourth hub motor are arranged at the left rear wheel and the right rear wheel of the automobile, and the rotors are fixedly connected with rims of the left rear wheel and the right rear wheel of the automobile respectively and are used for driving the left rear wheel and the right rear wheel of the automobile to rotate respectively;

the first rear straight gear is meshed with the second rear front straight gear, and a rotating shaft of the first rear straight gear is connected with a rotating shaft of the first rear steering gear through a first rear meshing gear ring; one end of the second rear straight gear rotating shaft is connected with the rotating shaft of the second rear steering gear through the second rear meshing gear ring, and the other end of the second rear straight gear rotating shaft is coaxially connected with the rotating shaft of the fifth driven bevel gear; the first rear steering gear and the second rear steering gear are meshed with the third steering rack, and the first rear steering gear and the second rear steering gear are not meshed with each other;

the third rear straight gear is meshed with the fourth rear front straight gear, one end of a rotating shaft of the third rear straight gear is connected with the rotating shaft of the third rear steering gear through a third rear meshed gear ring, and the other end of the rotating shaft of the third rear straight gear is coaxially connected with a rotating shaft of the sixth driven bevel gear; the fourth rear straight gear rotating shaft is connected with the rotating shaft of the fourth rear steering gear through the fourth rear meshing gear ring; the third rear steering gear and the fourth rear steering gear are meshed with the fourth steering rack, and the third rear steering gear and the fourth rear steering gear are not meshed with each other;

the third steering rack and the fourth steering rack are respectively arranged on the frames at the inner sides of the left rear wheel and the right rear wheel of the automobile and are both vertical to the steering shaft; the output ends of the third steering rack and the fourth steering rack are respectively connected with the left rear wheel and the right rear wheel of the automobile through the rear left conduction unit and the rear right conduction unit.

The vehicle speed sensor is used for acquiring the vehicle speed of the vehicle and transmitting the vehicle speed to the control module;

the driving mode switching module is used for sending a driving mode selected by a user to the control module, and the driving mode comprises four modes: a two-front-wheel steering mode, a four-wheel steering mode, a fixed-point zero-radius steering mode and a transverse driving mode;

the control module is respectively and electrically connected with the vehicle speed sensor, the running mode switching module, the first to fourth hub motors, the first to second front meshing gear rings and the first to fourth rear meshing gear rings and is used for controlling the first to fourth hub motors, the first to second front meshing gear rings and the first to fourth rear meshing gear rings to work according to data of the vehicle speed sensor and the running mode switching module.

As a further optimization scheme of the multi-mode steering mechanism of the wheel hub motor distributed electric drive automobile, the front left conduction unit, the front right conduction unit, the rear left conduction unit and the rear right conduction unit respectively comprise a steering tie rod, a steering knuckle and a control arm, wherein one end of the control arm is connected with a frame through a ball pin, and the other end of the control arm is connected with the steering knuckle; one end of the steering tie rod is connected with the steering knuckle;

the steering knuckles of the front left conducting unit, the front right conducting unit, the rear left conducting unit and the rear right conducting unit are fixedly connected with the centers of the stators of the first to fourth hub motors respectively; the other ends of the tie rods of the front left conducting unit, the front right conducting unit, the rear left conducting unit and the rear right conducting unit are respectively connected with the output ends of the first steering rack, the second steering rack, the third steering rack and the fourth steering rack.

As shown in fig. 5, the invention also discloses a two-front-wheel steering method of the wheel hub motor distributed electrically-driven automobile multi-mode steering mechanism, which comprises the following specific steps:

step A.1), a driver selects two front wheel steering modes through a driving mode switching module, and the driving mode switching module transmits the information to a control module;

step A.2), the control module controls the first rear meshing gear ring, the second rear meshing gear ring, the third rear meshing gear ring, the fourth rear meshing gear ring and the fourth rear meshing gear ring to be in a separated state, and controls the first front meshing gear ring, the second front meshing gear ring and the second front meshing gear ring to be in a meshed state;

step A.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to a first driven bevel gear and a second driven bevel gear through a steering column, a steering intermediate shaft, a steering shaft and a driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear and the second front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively.

As shown in fig. 6 and 7, the invention also discloses a four-wheel steering method of the multi-mode steering mechanism of the in-wheel motor distributed electric drive automobile, which comprises the following specific steps:

b.1), the driver selects a four-wheel steering mode through a driving mode switching module, and the driving mode switching module transmits the information to a control module;

step B.2), the control module controls the first rear meshing gear ring, the second rear meshing gear ring, the third rear meshing gear ring, the fourth rear meshing gear ring and the fourth rear meshing gear ring to be in a separated state, and controls the first front meshing gear ring, the second front meshing gear ring and the second front meshing gear ring to be in a meshed state;

step B.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to a first driven bevel gear and a second driven bevel gear through a steering column, a steering intermediate shaft, a steering shaft and a driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear and the second front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively;

b.4), the control module receives the speed sensor to obtain the speed of the automobile;

step B.5), the module controls the vehicle speed to be compared with a preset first speed threshold value;

step B.5.1), when the vehicle speed is less than a preset speed threshold value, the control module controls the second rear meshing gear ring and the third rear meshing gear ring to be in a separated state, and controls the first rear meshing gear ring and the fourth rear meshing gear ring to be in a meshing state; the first driven bevel gear drives a third steering rack to move sequentially through a fifth driven bevel gear, a second rear straight gear, a first rear straight gear and a first rear steering gear; the second driven bevel gear drives a fourth steering rack to move sequentially through a sixth driven bevel gear, a third rear straight gear, a fourth rear straight gear and a fourth rear steering gear, so that the steering directions of a left rear wheel and a right rear wheel are opposite to the steering directions of a left front wheel and a right front wheel, and the ratio of the wheel rotation angle of the left rear wheel and the right rear wheel to the wheel rotation angle of the left front wheel and the right front wheel is a preset first proportional threshold;

step B.5.2), when the vehicle speed is greater than a preset speed threshold value, the control module controls the first rear meshing gear ring and the fourth rear meshing gear ring to be in a separated state, and controls the second rear meshing gear ring and the third rear meshing gear ring to be in a meshing state; the first driven bevel gear drives a third steering rack to move sequentially through a fifth driven bevel gear, a second rear straight gear and a second rear steering gear; the second driven bevel gear drives the fourth steering rack to move sequentially through the sixth driven bevel gear, the third rear straight gear and the third rear steering gear, so that the steering directions of the left rear wheel, the right rear wheel and the left front wheel and the right front wheel are the same, and the ratio of the wheel rotation angle of the left rear wheel and the right rear wheel to the wheel rotation angle of the left front wheel and the wheel rotation angle of the right front wheel is a preset second proportional threshold.

As shown in fig. 8, the invention also discloses a fixed point zero radius steering method of the multi-mode steering mechanism of the wheel hub motor distributed electric drive automobile, which comprises the following specific steps:

step C.1), a driver selects a fixed-point zero-radius steering mode through a driving mode switching module, and the driving mode switching module transmits the information to a control module;

step C.2), the control module controls the first front meshing gear ring to be in a meshing state, controls the second front meshing gear ring to be in a separating state and cuts off a power source of the second front steering gear;

step C.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to the first driven bevel gear and the second driven bevel gear through the steering column, the steering intermediate shaft, the steering shaft and the driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear, the first front straight gear and the first front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively, so that the turning angles arctan (L/d) of the left front wheel and the right front wheel are enabled, L represents the automobile wheelbase, d represents the wheelbase, and the steering of the two front wheels is completed;

step C.4), the control module controls the first rear meshing gear ring and the third rear meshing gear ring to be in a separated state, and controls the second rear meshing gear ring and the fourth rear meshing gear ring to be in a meshed state; the first driven bevel gear drives a third steering rack to move sequentially through a first transmission bevel gear, a fifth driven bevel gear, a second rear straight gear and a second rear steering gear; the second driven bevel gear drives a fourth steering rack to move sequentially through a second transmission bevel gear, a sixth driven bevel gear, a third rear straight gear, a fourth rear straight gear and a fourth rear steering gear; the third steering rack and the fourth steering rack transmit the steering torque of the steering wheel to the left rear wheel and the right rear wheel through the rear left transmission unit and the rear right transmission unit respectively, so that the turning angles of the left rear wheel and the right rear wheel of the automobile are arctan (L/d).

As shown in fig. 9, the invention also discloses a transverse driving method of the multi-mode steering mechanism of the wheel hub motor distributed electric drive automobile, which comprises the following specific steps:

step D.1), the driver selects a transverse driving mode through the driving mode switching module, and the driving mode switching module transmits the information to the control module;

d.2), the control module controls the first front meshing gear ring to be in a meshing state and controls the second front meshing gear ring to be in a separating state, and a power source of the second front steering gear is cut off;

step D.3), when a driver rotates a steering wheel, the torque of the steering wheel is sequentially transmitted to a first driven bevel gear and a second driven bevel gear through a steering column, a steering intermediate shaft, a steering shaft and a driving bevel gear respectively; the first driven bevel gear drives the first steering rack to move sequentially through the first transmission bevel gear, the third driven bevel gear, the second front straight gear, the first front straight gear and the first front steering gear; the second driven bevel gear drives a second steering rack to move sequentially through a second transmission bevel gear, a fourth driven bevel gear and a third front steering gear; the first steering rack and the second steering rack transmit the steering torque of the steering wheel to the left front wheel and the right front wheel through the front left transmission unit and the front right transmission unit respectively, so that the turning angles of the left front wheel and the right front wheel are 90 degrees, and the steering of the two front wheels is completed;

d.4), the control module controls the first rear meshing gear ring and the third rear meshing gear ring to be in a separated state, and controls the second rear meshing gear ring and the fourth rear meshing gear ring to be in a meshed state; the first driven bevel gear drives a third steering rack to move sequentially through a first transmission bevel gear, a fifth driven bevel gear, a second rear straight gear and a second rear steering gear; the second driven bevel gear drives a fourth steering rack to move sequentially through a second transmission bevel gear, a sixth driven bevel gear, a third rear straight gear, a fourth rear straight gear and a fourth rear steering gear; the third steering rack and the fourth steering rack transmit the steering torque of the steering wheel to the left rear wheel and the right rear wheel through the rear left transmission unit and the rear right transmission unit respectively, so that the rotation angles of the left rear wheel and the right rear wheel of the automobile are 90 degrees.

It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The above-mentioned embodiments, objects, technical solutions and advantages of the present invention are further described in detail, it should be understood that the above-mentioned embodiments are only illustrative of the present invention and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.