CN216185449U

CN216185449U - A drive-by-wire a steering system for heavy commercial car

Info

Publication number: CN216185449U
Application number: CN202122732182.XU
Authority: CN
Inventors: 汪选要; 许金鹏; 马成程; 周俊
Original assignee: Anhui University of Science and Technology
Current assignee: Anhui University of Science and Technology
Priority date: 2021-11-09
Filing date: 2021-11-09
Publication date: 2022-04-05
Anticipated expiration: 2031-11-09

Abstract

The invention discloses a steer-by-wire system for a heavy commercial vehicle, which comprises a steering wheel, a steering column, a road sensing motor, a torque/corner sensor, an electromagnetic clutch, a worm gear and worm speed reducing mechanism, a recirculating ball type steering gear, a steering motor and a control unit. Has the advantages that: a hydraulic pump and an oil tank are eliminated, and no complex oil way and oil way accessories need to be assembled; a planetary gear reducer with higher transmission efficiency than a worm gear reducer is adopted; the electromagnetic clutch is arranged on the steering column, so that the mechanical steering capacity of the steering system is reserved, and the fault tolerance of the steering system is improved; the steering function requirements of auxiliary driving and automatic driving can be met.

Description

A drive-by-wire a steering system for heavy commercial car

Technical Field

The invention relates to a steer-by-wire system for a heavy commercial vehicle, belonging to the field of automobile steering devices.

Background

At present, recirculating ball-type hydraulic power-assisted steering gears are mainly used for heavy commercial vehicles. Conventional hydraulic power steering gears have a number of disadvantages: (1) the speed of a vehicle is improved, and the flow is improved to influence the hand feeling. The contradiction between high-speed stability and low-speed portability exists; (2) the engine outputs rated flow when idling, and for a normal flow type system, an oil pump works when the engine does not turn, and additional fuel consumption is large.

The patent with the publication number of CN108820035A discloses a steering control method of a wire-controlled hydraulic steering system of a commercial vehicle, wherein the system comprises a steering wheel module, a mechanical steering module, a hydraulic transmission module and a control module. An ECU in the control module outputs signals to control a hydraulic pump driving motor and an electromagnetic directional valve to work, and a connecting rod mechanism is driven to change the rotation angle of wheels by changing the oil pressure on two sides of a piston of a hydraulic cylinder; the ECU also outputs current signals, and the current signals are fed back to a driver through a road sense motor to correspond to road senses, so that the wire control hydraulic steering is completed.

The invention patent with the publication number of CN105501293A discloses an electric hydraulic steering system for a commercial vehicle, which comprises a circulating ball steering gear, an intermediate shaft, a mandrel, a worm wheel, a worm, a sensor, a supporting seat, a motor and a controller; a middle shell is fixedly arranged on one side of a connecting valve body of the recirculating ball steering gear through a connecting screw, a mandrel is arranged in the middle shell through a bearing A, one end of the mandrel is in keyed connection with an input shaft of the recirculating ball steering gear, the other end of the mandrel extends to the outer end of the middle shell, an intermediate shaft is movably sleeved on the mandrel in the middle shell, and the intermediate shaft is connected with a steering screw of the recirculating ball steering gear.

The two inventions optimize the traditional hydraulic power steering gear by additionally arranging the motor, the first invention reduces the fuel consumption to a certain extent by providing power for the hydraulic pump through the motor, and can realize steer-by-wire by controlling the motor, but the steering gear in the design has slower steering speed; the second invention patent reduces the hydraulic power needed by the steering through the combined work of the motor and the hydraulic power, thereby achieving the purpose of energy saving, but the coupling of the hydraulic power and the electric power in the design makes the control system of the steering more complicated, and the cost is also increased.

Disclosure of Invention

The invention aims to provide a steer-by-wire system for a commercial vehicle, which can remove a steering pump and hydraulic oil from the steering system, improve the transmission efficiency, reduce the energy loss and reduce the environmental pollution, and can set a variable transmission ratio in real time according to the running condition of the vehicle by a controller, thereby increasing the driving comfort and reducing the potential safety hazard.

In order to achieve the purpose, the invention adopts the following technical scheme: the utility model provides a drive-by-wire steering system for heavy commercial car, includes way sense analogue means, controller and initiative steering device, way sense analogue means includes steering wheel, steering column, torque angle sensor, worm gear speed reducer device and way sense motor, the bottom of way sense analogue means is provided with electromagnetic clutch, the steering column bottom is connected with the steering jackshaft through the universal joint, the steering jackshaft bottom is connected with the initiative steering device through the universal joint, the initiative steering device includes circulation ball formula steering gear, planetary gear reduction gear and steering motor, the inside angle sensor that is provided with of circulation ball formula steering gear.

The bottom of the steering wheel is fixedly connected with a steering column, a worm wheel is arranged in the middle of the steering column, a road sensing motor is arranged on one side of the steering column, a worm is fixedly mounted on an output shaft of the road sensing motor, the worm is in transmission connection with the worm wheel, a torque angle sensor is mounted on the steering column between the steering wheel and the worm wheel, and the torque angle sensor is a dual-channel angle sensor.

The controller is electrically connected with a steering motor, a road sensing motor and an electromagnetic clutch and controls work, and the controller is electrically connected with a torque corner sensor and a circulating ball type steering gear internal corner sensor and is in signal connection.

The steering gear shell is fixedly connected with the planetary gear reducer shell through a spigot structure, the steering gear shell is fixedly connected with the planetary gear reducer shell through the spigot structure, the steering motor is a 48V direct current brushless servo large-torque motor, the planetary gear reducer is a two-stage planetary gear reducer, and the reduction ratio range is 10-30.

The other end of a steering rocker arm of the steering gear is connected with a steering drag link in a sliding mode through a ball pin, and the other end of the steering drag link is connected with a steering knuckle arm in a sliding mode through the ball pin.

The invention has the beneficial effects that:

1. the invention can set variable transmission ratio, reduce the burden of a driver when the vehicle runs at low speed and improve the response capability of the steering system of the commercial vehicle; the steering of the vehicle is more stable when the vehicle runs at a high speed, and the safety of the commercial vehicle is improved; and the steering road feeling is simulated, so that the driver is helped to acquire road surface information, and the comprehensive judgment capability of the driver on the vehicle and the road surface condition is enhanced.

2. The invention eliminates a steering pump and a hydraulic oil tank, has no complex oil circuit and oil circuit accessories needing to be assembled, has no oil leakage problem and can not cause environmental pollution.

3. The invention adopts the motor to provide power for the steering gear, the steering gear is internally provided with the corner sensor, the corner of the steering gear can be monitored in real time, the intelligent driving functions of active steering, lane keeping and the like can be realized, the steering is light and flexible, and the energy loss is reduced and the transmission efficiency is improved by adopting the planetary gear speed reducing mechanism.

4. The invention adopts a redundancy design, improves the fault tolerance of the steering system and avoids the safety problem caused by the failure of the steering system due to the motor failure.

Drawings

FIG. 1 is a schematic structural view of the present invention; FIG. 2 is a schematic view showing the construction of a steering gear according to the present invention

1. Road feel simulation device 2, controller 3, active steering device

4. Steering gear 5, planetary gear reducer 6 and steering motor

7. Steering wheel 8, steering column 9, torque angle sensor

10. Road feel motor 11, electromagnetic clutch 12, steering column jackshaft

13. Steering rocker 14, steering drag link 15 and knuckle arm

16. Trapezoidal arm 17, steering tie rod

401. Input shaft 402, sensor rotor 403, and sensor stator

404. Torsion bar 405, intermediate housing 406, and steering gear housing

407. Output shaft 408, steering nut 409 and balls

410. Spiral trajectory 411, steering screw

501. Planet carrier II 502, planet wheel pin II 503 and planet wheel II

504. Sun gear II 505, sun shaft II 506 and inner gear ring

507. Planet carrier I508, planet wheel pin I509 and planet wheel I

510. Sun gear one 511 and sun shaft one

Detailed Description

The following detailed description of the embodiments of the present invention will be given with reference to the accompanying drawings for a purpose of helping those skilled in the art to more fully, accurately and deeply understand the concept and technical solution of the present invention and to facilitate its implementation.

It should be noted that, in the following embodiments, the "first" and "second" do not represent an absolute distinction relationship in structure and/or function, nor represent a sequential execution order, but merely for convenience of description.

The steer-by-wire system assembly for the heavy commercial vehicle is characterized in that the steering wheel (7) is assembled at the top end of the steering column (8), the torque angle sensor (9) and the electromagnetic clutch (11) are sequentially assembled on a steering intermediate shaft (8), and the bottom end of the steering intermediate shaft (12) is connected with the steering gear (4) through a universal joint.

The invention relates to a steering angle sensor (9) and a steering angle sensor which are connected with a controller (2), wherein the steering angle sensor (9) can output a steering angle signal, a torque signal and a self-checking signal to the controller (2), the steering angle sensor can also output a steering angle signal to the controller (2), and a road sensing motor (10), an electromagnetic clutch (11) and a steering motor (6) are connected with the controller (2) and controlled by the controller (2) to work. The road sensing motor (10) and the steering motor (6) are direct-current brushless servo motors, motor driving modules are arranged in the road sensing motor (10) and the steering motor (6), the road sensing motor (10) and the steering motor (6) are respectively provided with a motor position sensor and a current sensor, the rotor positions and the steering currents of the road sensing motor (10) and the steering motor (6) can be measured, the working states of the road sensing motor (10) and the steering motor (6) can be monitored, and alarm signals are output to the controller (2) when the road sensing motor (10) and the steering motor (6) are in fault.

When a driver controls the vehicle to steer, the driver rotates a steering wheel (7), steering torque and steering angle are transmitted to a torque corner sensor (9) through a steering column (8), the torque corner sensor collects signals of the magnitude of the rotating torque and the rotating direction acting on the steering wheel (7) and the rotating angle of the steering wheel (7) and sends the signals to a controller (2), the controller (2) processes the signals of the magnitude of the rotating torque and the rotating direction acting on the steering wheel (7) and the signals of the rotating angle of the steering wheel, outputs current and signals of the rotating direction to a steering motor (6), the steering motor (6) rotates, after passing through a steering gear (4), wheels are driven to steer through a knuckle arm (15) and a tie rod (17), and the controller (2) calculates the rotating angle of an output shaft (407) relative to a sensor stator (403) through a sensor rotor (410), controller (2) will be through the back of the road feel signal processing that the sensor received, output current and direction of rotation signal to road feel motor (10), transmit steering wheel (7) through steering column (8), provide the road feel for the driver, when turning to motor (6) trouble failure, controller (2) are closed through controlling electromagnetic clutch (11), the driver can provide steering torque through mechanical steering, guarantee the reliability of turning to under the electronic steering trouble, prevent that the vehicle from losing the power of turning to take place the accident because of turning to, promote whole car and take advantage of the security.

When the vehicle automatically steers, the whole vehicle collects the current required steering angle and transmits a turning angle signal to the controller (2); after receiving the steering angle, the controller (2) outputs a current and a rotation direction signal to the steering motor (6) and outputs the current and the rotation direction signal to the steering gear (4); after receiving the rotation angle transmission of a steering motor (6), the steering gear (4) drives a steering tie rod (17) through the transmission of a steering rocker arm (13), a steering tie rod (14), a steering knuckle arm (15) and a trapezoidal arm (16) to realize steering; the steering angle sensor in the steering gear (4) feeds back the measured steering angle signal to the controller (2), and the controller (2) compares the required steering angle signal with the measured steering angle signal to complete automatic steering.

The secondary planetary gear speed reducing mechanism comprises an assembly shell, two sets of sun shafts, a planet carrier and planet wheels, wherein a sun shaft I (511) is installed in the assembly shell through a bearing, one end of the sun shaft I (511) is connected with a steering motor (6), the other end of the sun shaft I (511) is provided with a sun wheel I (510) through pin connection, the sun wheel I (510) is meshed with four planet wheel I (509), the four planet wheel I (509) is meshed with an inner gear ring (506) on the assembly shell, one end of a planet wheel pin I (508) is in interference connection with the planet carrier I (507), the other end of the planet wheel pin I (508) is movably connected with the planet wheel I (509) through a sliding bearing, the other end of the planet carrier I (507) is fixedly connected with a sun shaft II (505) through a pin, the other end of the sun shaft II (505) is provided with a sun wheel II (504) through pin connection, and the sun wheel II (504) is meshed with the four planet wheel II (503), the four second planet wheels (503) are meshed with an inner gear ring (506) on the assembling shell, one end of a second planet wheel pin shaft (502) is in interference connection with the second planet wheel (501), the other end of the second planet wheel pin shaft (502) is movably connected with the second planet wheels (503) through a sliding bearing, and the other end of the second planet wheel (501) is fixedly connected with a steering screw rod (411) through a pin.

The circulating ball type steering gear consists of a steering gear shell (406), a steering screw rod (411), a steering nut (408), an output shaft (407) and a sensor, wherein the steering screw rod (411) is movably installed in the steering gear shell (406) through a bearing, the steering nut (408) is movably sleeved on the steering screw rod (411), spiral trajectories (410) are respectively arranged on the circumference of the steering screw rod (411) and the inner wall of the steering nut (408), the spiral trajectories (410) are movably connected with each other through balls (409), the spiral trajectories (410) are matched with the balls (409) to convert sliding friction between the steering nut (408) and the steering screw rod (411) into rolling friction between the steering nut (408) and the balls (409) and between the steering screw rod (411) and the balls (409), thereby reducing frictional resistance and reducing wear of the steering screw (411) and the steering nut (406); an output shaft (407) is arranged on the steering gear shell (406) on one side of the steering screw rod (411), the end head of the output shaft (407) is meshed with a steering nut (408), and when the steering nut (408) moves along the steering screw rod (411) under the action of the steering screw rod (411), the steering nut (408) can drive the output shaft (407) to rotate, so that wheels connected with the output shaft (407) can be driven to deflect to steer; a sensor is arranged on a steering gear shell (406) at one end head of the steering screw rod (411); the sensor is composed of an input shaft (401), a torsion bar (404), a sensor stator (403) and a sensor rotor (402), wherein the input shaft (401) is a tubular body, and the input shaft (401) is movably connected with a steering screw rod (411) through a sliding bearing; a torsion bar (404) is inserted in the input shaft (401), and the torsion bar (404) is connected with the input shaft (401) through a cylindrical pin; a sensor stator (403) is welded on the circumference of the input shaft (401), a sensor rotor (402) is sleeved on the input shaft (401) on one side of the sensor stator (403), and the sensor rotor (402) is fixedly connected with a steering screw (411); the torsion bar (404) is connected with the steering screw (411) in a plug-in manner; the middle shell (405) is movably connected with the steering screw rod (411) through a bearing; the end head of the other end of the steering screw rod (411) is fixedly connected with a second planet carrier (501); when the second planet carrier (501) rotates, the second planet carrier (501) drives the steering screw (411) to rotate, the steering screw (411) drives the sensor rotor (402) to rotate, meanwhile, the steering screw (411) drives the torsion bar (404) to rotate, further, the torsion bar (404) drives the input shaft (401) to rotate, the sensor stator (403) is driven to rotate in the rotation process of the input shaft (401), the torsion bar (404) deforms in the rotation process of the input shaft (401), the sensor rotor (402) deflects relative to the sensor stator (403), the rotation angle of the steering screw (411) is measured through the deflection angle of the sensor rotor (402) relative to the sensor stator (403), further, the stroke of the steering nut (408) relative to the steering screw (411) is measured, and therefore the rotation angle of the input shaft (401) is measured; the sensor rotor (402) and the sensor stator (403) are respectively connected with the controller (2), the controller (2) detects the states of the sensor rotor (402) and the sensor stator (403), and when the sensor rotor (402) deflects relative to the sensor stator (403), the controller (2) calculates the rotation angle of the output shaft (407) according to the deflection angle of the sensor rotor (402) relative to the sensor stator (403).

Claims

1. A steer-by-wire system for heavy commercial vehicle, includes road feel analogue means (1), controller (2) and initiative steering gear (3), its characterized in that: road feel analogue means (1) is including steering wheel (7), steering column (8), torque angle sensor (9), worm gear speed reducer and road feel motor (10), the bottom of road feel analogue means (1) is provided with electromagnetic clutch (11), steering column (8) bottom is connected with steering intermediate shaft (12) through the universal joint, steering intermediate shaft (12) bottom is connected with initiative steering device (3) through the universal joint, initiative steering device (3) are including circulation ball formula steering gear (4), planetary gear reducer (5) and steering motor (6), circulation ball formula steering gear (4) inside is provided with angle sensor.

2. A steer-by-wire system for a heavy commercial vehicle according to claim 1, wherein: the steering wheel is characterized in that a steering column (8) is fixedly connected to the bottom of the steering wheel (7), a worm wheel is arranged in the middle of the steering column (8), a road sensing motor (10) is arranged on one side of the steering column (8), a worm is fixedly mounted on an output shaft of the road sensing motor (10), the worm is in transmission connection with the worm wheel, a torque corner sensor (9) is mounted on the steering column (8) between the steering wheel (7) and the worm wheel, and the torque corner sensor (9) is a double-channel corner sensor.

3. A steer-by-wire system for a heavy commercial vehicle according to claim 1, wherein: the controller (2) is electrically connected with the steering motor (6), the road sensing motor (10) and the electromagnetic clutch (11) and controls work, and the controller (2) is electrically connected with the torque corner sensor (9) and the internal corner sensor of the circulating ball type steering gear (4) and is in signal connection.

4. A steer-by-wire system for a heavy commercial vehicle according to claim 1, wherein: the steering gear (4) shell and the planetary gear reducer (5) shell are fixedly connected through a spigot structure, the steering motor (6) is a 48V direct-current brushless servo large-torque motor, the planetary gear reducer (5) is a two-stage planetary gear reducer, and the reduction ratio range is 10-30.

5. A steer-by-wire system for a heavy commercial vehicle according to claim 1, wherein: the other end of a steering rocker arm (13) of the steering gear (4) is in sliding connection with a steering drag link (14) through a ball pin, and the other end of the steering drag link (14) is in sliding connection with a steering knuckle arm (15) through the ball pin.