CN203996474U - Automatically controlledly turn to servo-actuated mudguard for vehicle wheel device - Google Patents

Abstract

The utility model discloses an electric control steering wheel fender device, which comprises an electric control system, at least two stepping motors and at least two fenders; The inner side; the fenders are respectively installed on the output shaft of the stepping motor; the electronic control system includes a rotation angle sensor, a vehicle power supply and an electronic control unit, wherein the rotation angle sensor is installed on the steering shaft of the automobile; the electronic control unit is respectively connected with the rotation angle sensor and the The stepping motor is electrically connected to receive the data transmitted by the rotation angle sensor and control the rotation of the stepping motor. The beneficial effect is: it can effectively block the flying stones stirred up by the tires, avoiding safety accidents; it can effectively block the stones splashed by the high-speed rotating tires when turning, and avoid injuring rear vehicles and pedestrians; it can avoid fenders Scratching and movement interference with the wheel cover plate; stable and reliable work; the gap between the fender and the outer edge of the tire is not easy to block, ensuring the wheel to rotate freely.

Description

Electronic control steering follower wheel fender device

technical field

The utility model relates to an electronically controlled protection device applied to automobiles, more precisely, the utility model particularly relates to an electronically controlled steering wheel fender device which can move with the steering wheel.

Background technique

With the increase of car ownership and usage rate, the driving safety of cars has been paid more and more attention by people. With the increase of the driving speed of the car, there are often accidents on the highway where the front tire rolls up stones and splashes and damages the front windshield of the rear car and pedestrians, and even on the expressway, there are occasions when the front car rolls up stones and splashes and breaks through the windshield Accidents injuring passengers.

The fixed fenders of automobiles that are now in use are mainly used to prevent the body of the vehicle from being polluted by muddy water and scratched by stones. Due to the width limitation and the fixed installation method, it can prevent the steering wheel from stirring up flying stones and injuring the rear car and pedestrians. The effect is not ideal. For this reason, some movable fender devices have appeared, such as:

1. The fender described in the Chinese patent "automobile steering wheel follower fender" (patent number: 200620035562.0) is fixed on the car steering knuckle by a bracket and can rotate around the steering knuckle pin synchronously with the steering wheel, and is always connected with the steering wheel A mechanical device that maintains a constant position.

2. The European patent "Adjustable Mudguard" (Patent No.: EP851044881985-04-12) is a mechanical rotating mudguard installed on the wheel axle and capable of adjusting the axial and radial positions.

Most of the steering follower fenders and their transmission devices proposed in the above-mentioned related patents are placed on the steering knuckle or the wheel shaft, which makes installation and maintenance difficult; sludge, ice and snow tend to remain between the wheels and the fenders, increasing the friction The resistance makes it difficult for the wheel to turn; and because it is a purely mechanical device, when the fender turns inward with the wheel, it is easy to rub against the inner wheel cover plate of the vehicle body at the extreme position.

Contents of the invention

The purpose of this utility model is to solve the above-mentioned problems existing in the prior art, and to provide an electronically controlled steering follower wheel fender device, which can effectively block the stones splashed by the rotating tires, and avoid injuring rear vehicles and pedestrians , and can avoid the motion interference of the fender movement and the wheel cover plate inside the vehicle body; and further realize a mechanical structure of the electronically controlled rotatable wheel fender.

The electric control steering follower wheel fender device involved in the utility model includes an electric control system, a stepping motor and a fender;

At least two stepping motors are respectively mounted on the inner side of the wheel housing plate of the driving wheel of the automobile, and are used to receive the control signal of the electric control system and drive the two fenders to rotate respectively;

At least two fenders are respectively installed on the output shaft of the stepping motor, and are deflected through the control of the stepping motor to effectively block the stones splashed by the rotating tire;

The electronic control system includes a rotation angle sensor, an on-board power supply and an electronic control unit, wherein:

A rotation angle sensor, installed on the steering shaft of the automobile, is used to detect the rotation angle of the steering wheel of the automobile and transmit the detection data to the electronic control unit;

The electronic control unit is electrically connected with the rotation angle sensor and the stepping motor respectively, and is used for receiving the data transmitted by the rotation angle sensor and controlling the rotation of the stepping motor.

Preferably, the stepping motors are respectively fixed on the inner side of the wheel cover plate through a connecting plate and bolts, and a rectangular hole is arranged on the wheel cover plate corresponding to the stepping motor, and the corresponding output shaft of the stepping motor side of the rectangular shell clearance fit.

Preferably, the connecting plate is a rectangular flat plate with a through hole in the center, and two circles of evenly distributed connecting holes are respectively arranged around the through hole of the connecting plate to connect the stepping motor and the wheel cover respectively. plate.

Preferably, the fenders are respectively installed on the output shaft of the stepper motor through a spline shaft, and the fenders are an integral structure composed of an upper handle, a lower panel and a spline hub arranged at the upper end of the upper handle, The center of the spline hub is provided with a spline hole and matched with the spline shaft to facilitate installation and ensure reliable transmission.

Preferably, the length of the spline hub in the axial direction is greater than the thickness of the upper handle and the lower panel, and the outer cylinder and the rounded corners on both sides of the upper handle smoothly transition to play a role of local connection reinforcement.

Preferably, the fender is a "knife"-shaped and integrally concave panel part injection-molded by engineering plastics at one time, so as to facilitate processing and reduce manufacturing costs.

Preferably, the rotation angle sensor is installed in a protective casing, and is fixed on the automobile steering shaft bracket through the protective casing.

Preferably, the electronic control unit includes a single-chip microcomputer, a power supply module and a stepping motor driver corresponding to the stepping motor respectively, the input port of the single-chip microcomputer is connected to the data output end of the described rotation angle sensor, and the control output end of the single-chip microcomputer is connected to the stepping motor respectively. The signal input end of the motor driver is electrically connected, the power input end of the power module is connected to the vehicle power supply, the power output end of the power module is respectively electrically connected with the rotation angle sensor, the single-chip microcomputer and the stepper motor driver, and the output ends of the stepper motor driver are respectively connected with the Corresponding stepper motors are electrically connected.

The beneficial effects of the utility model are:

1. Because the wheel fender described in the utility model can realize the follow-up deflection with the wheel steering through the control of the stepping motor, it can effectively block the flying stones stirred up by the tire and avoid causing safety accidents; The stones splashed during the turn can be effectively blocked to avoid injuring the rear vehicles and pedestrians.

2. Since the wheel fender described in the utility model adopts the electronic control unit to control the rotation direction and the size of the corner accurately, it avoids the uncontrollable disadvantage of the mechanical steering follow-up fender, and the outer rear edge of the wheel faces the inner side of the car body When swinging, the fender is controlled by the electronic control unit to keep it in the initial position, which can effectively avoid scratching and movement interference with the wheel cover plate;

3. The wheel fender of the utility model uses the angle sensor to estimate the rotation angle and direction of the wheel through the electronic control system, and uses the angle to indirectly judge the driving speed of the car, so as to determine whether the wheel fender rotates and the angle and direction of the rotation Direction; thus ensuring stable and reliable work.

4. Since the wheel fender is installed on the wheel cover plate of the car body through a stepping motor, it avoids the installation of the follow-up fender on the wheel in the prior art, and the resulting snow and mud can easily block the outer surface of the tire. Due to the technical problem of the narrow space between the fender and the fender, a mechanical structure of an electronically controlled rotatable fender is realized, so that the gap between the fender and the outer edge of the tire is not easy to be blocked, thereby ensuring the wheel to rotate freely.

Description of drawings

Fig. 1 is a schematic diagram of the installation position of the system of the present utility model.

Fig. 2 is a partial view of the steering shaft of the present invention.

Fig. 3 is a schematic diagram of the assembly of the rotation angle sensor and the steering shaft described in the present invention.

Fig. 4 is an axial exploded view of the assembly of the steering wheel angle sensor and the protective casing according to the present invention.

Fig. 5 is a partial view of the inner side of the wheel house plate described in the utility model.

Fig. 6 is a schematic diagram of the assembly of the stepping motor and the wheel cover plate of the present invention.

Fig. 7 is a sectional view of the spline shaft of the present invention.

Fig. 8 is an axial exploded view of the assembly relationship between the stepping motor and the fender of the present invention.

Fig. 9 is a block diagram of the electronic control system of the present invention.

Fig. 10 is an electrical schematic diagram of the connection between the rotation angle sensor and the single-chip microcomputer described in the utility model.

Fig. 11 is an electrical schematic diagram of the connection between the stepping motor driver and the single-chip microcomputer described in the utility model.

Fig. 12 is a schematic diagram of the working principle of the fender deflection described in the present invention.

Fig. 13 is a program flow diagram of the electric control unit of the utility model.

In the figure: 1. Steering wheel, 2. Steering shaft, 201. Strip card slot, 3. Angle sensor, 301. Rectangular wiring slot, 302. Inner rotor, 303. Rectangular boss, 4. Electronic control unit, 5 , fender, 6, stepping motor, 7, wheel cover plate, 701, rectangular hole, 702, through hole, 8, connecting plate, 9, connecting plate bolt, 10, motor bolt, 11, screw, 12, upper Cover plate, 1201, through hole, 13, lower housing, 1301, inner chamber, 1302, through hole, 1303, rectangular through hole, 14, fixing nut, 15, spline shaft, 1501, stepped through hole, 1502, Annular groove, 16, snap ring, 17, limit screw, 18, vehicle power supply, 19, stepper motor driver, 20, power supply module, 21, single-chip microcomputer.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is described in detail.

The innovation point of the utility model is that the fender of the steering follower wheel applies electronic control technology, which realizes the purpose of the fender to realize the electric steering follow-up according to different working conditions. Referring to FIG. 1 , the electric control steering follower wheel fender device of the present invention mainly includes an electric control system, at least two stepping motors 6 and at least two fenders 5 . The quantity of the stepping motor 6 and the fender 5 is determined according to the number of the driving wheels of the automobile. In the present embodiment, the front wheel drive is taken as an example, so the quantity of the stepping motor and the fender is two respectively as an example.

As shown in Fig. 1 and Fig. 5, described stepper motor 6 is fixedly installed on the inner side of the wheel house plate 7 of automobile left and right front wheel by a connecting plate 8 and bolt respectively, is used for receiving the control signal of described electronic control system and The fenders 5 are driven to rotate respectively, which can avoid being damaged by rainwater erosion. A rectangular hole 701 is provided on the wheel cover plate 7 corresponding to the stepping motor 6 , and the rectangular hole 701 is in clearance fit with the rectangular housing on the side corresponding to the output shaft of the stepping motor 6 . Four through holes 702 are evenly arranged on the four corners of the wheel house plate 7 near the rectangular hole 701 , and fixing nuts 14 are respectively welded on the inner side of the wheel house plate 7 corresponding to the through holes 702 .

As shown in Figures 6 and 8, the connecting plate 8 is a rectangular flat plate and the center is provided with a through hole, the diameter of which is slightly larger than the outer diameter of the spline shaft 15 installed on the output shaft of the stepping motor 6, when connecting Two circles of evenly distributed connection holes are respectively provided around the through hole of the plate 8 to connect the stepping motor 6 and the wheel cover plate 7 respectively. The output shaft of the stepper motor 6 passes through the through hole in the center of the connecting plate 8 and is keyed to the spline shaft 15. The connecting plate 8 is connected to the stepping motor 6 through the motor bolt 10 passing through the connecting hole of its inner ring. The rectangular housing is fixed, and the connecting plate 8 is fixed on the outside of the wheel house plate 7 through the connecting plate bolts 9 passing through the connecting holes of its outer ring, and the connecting plate bolts 9 are screwed into the corresponding fixing nuts 14 respectively.

As shown in FIG. 7 , the spline shaft 15 is made of engineering plastics, a stepped through hole 1501 is provided in the axial center, and a spline groove is processed on the outer wall. As shown in FIG. 8 , the fenders 5 are respectively installed on the output shafts of the stepper motors 6 through the spline shafts 15 , and are controlled by the stepper motors 6 to deflect and effectively block the stones splashed by the rotating tires. The fender 5 is a "knife"-shaped plate part that is integrally concaved by one-time injection molding of engineering plastics, so as to facilitate processing and reduce manufacturing costs. The fender 5 is an integral structure consisting of an upper handle, a lower panel and a spline hub located at the upper end of the upper handle. The center of the spline hub is provided with a spline hole and is connected to the spline shaft 15 Match the spline groove on the top. The length of the spline hub in the axial direction is greater than the thickness of the upper handle and the lower panel, and the outer cylinder and the rounded corners on both sides of the upper handle smoothly transition to play the role of local connection reinforcement. The fender 5 is inserted on the spline shaft 15 through its spline hub, an annular groove 1502 is arranged on the outside of the fender 5 on the spline shaft 15, and a snap ring is installed in the annular groove 1502 16, to realize the axial limit of the fender 5. The spline shaft 15 outer end is provided with the limit screw 17 that inserts in its stepped through hole 1501, the limit screw 17 inner end is threadedly connected with the central hole of the stepper motor 6 output shaft, and the hexagonal big head of the limit screw 17 is stuck in Inside the outer port of the stepped through hole 1501 .

As shown in FIGS. 1 and 9 , the electronic control system includes a rotation angle sensor 3 , a vehicle power supply 18 and an electronic control unit 4 . The rotation angle sensor 3 is installed on the steering shaft 2 of the automobile, and is used to detect the rotation angle of the steering wheel 1 of the automobile and transmit the detection data to the electronic control unit 4 .

As shown in FIG. 2 and FIG. 3 , the steering shaft 2 is a cylindrical stepped shaft, and a bar-shaped locking groove 201 is provided in the axial direction on the large-diameter shaft section at the stepped shoulder. The rotation angle sensor 3 is an integrated structure composed of a circular body and a rectangular wiring slot 301 , and the wiring slot is the terminal of the rotation angle sensor 3 . An inner rotor 302 with a light hole is arranged in the inner hole of the circular ring of the rotation angle sensor 3, and a rectangular boss 303 is arranged axially on the inner wall of the inner rotor 302, and the rectangular boss 303 snaps into the In the bar-shaped slot 201 of the steering shaft 2 , the steering shaft 2 drives the inner rotor 302 of the rotation angle sensor 3 to rotate relative to the outer shell of the rotation angle sensor 3 through the rectangular boss 303 , thereby measuring the rotation angle of the steering wheel 1 . As a non-restrictive preference, the utility model chooses the LH3 steering wheel angle sensor commonly used in the existing electric power steering system, but it is not limited to this type of steering wheel angle sensor, and there is no difference in selecting other types of steering wheel angle sensors. The new structure of the electric control steering follower wheel fender 5 described in the utility model still belongs to the protection scope of the utility model.

As shown in FIG. 4 , the rotation angle sensor 3 is installed in a protective casing, and is fixed on the steering shaft bracket of the automobile through the protective casing. The protective shell is formed by connecting the lower shell 13 and the upper cover plate 12 through screws 11 evenly distributed at the four corners. The lower shell 13 is a rectangular thick plate with a certain thickness, and an inner Chamber 1301, the inner contour shape of the inner chamber 1301 is consistent with the shape of the angle sensor 3, and is formed by a circular inner cavity and a rectangular groove. The angle sensor 3 is placed in the inner chamber 1301 and Packaged by the upper cover plate 12. A through hole 1302 is provided at the bottom center of the circular inner chamber of the inner chamber 1301 , and the diameter of the through hole 1302 is slightly larger than the diameter of the large-diameter shaft section of the steering shaft 2 . A rectangular through hole 1303 communicating with the inner chamber 1301 is provided on the outer wall of the lower housing 13 corresponding to the side of the rectangular groove, and the width of the rectangular through hole 1303 is consistent with the rectangular groove. The upper cover plate 12 is a rectangular flat piece, and a through hole 1201 is arranged in the center of the upper cover plate 12 , and the diameter of the through hole 1201 is slightly larger than the diameter of the small-diameter shaft section of the steering shaft 2 . The steering shaft 2 passes through the protective shell and the rotation angle sensor 3 from the bottom of the lower housing 13 .

As shown in Fig. 1 and Fig. 9, described electronic control unit 4 is installed under the automobile dashboard and is electrically connected with angle sensor 3, on-board power supply 18 and stepper motor 6 respectively, is used for receiving the data that angle sensor 3 transmits and controls The rotation of stepper motor 6. The on-board power supply 18 is the original 12V on-board power supply of the automobile.

Described electronic control unit 4 comprises single-chip microcomputer 21, power supply module 20 and stepper motor driver 19 corresponding with stepper motor 6 respectively, the input port of single-chip microcomputer 21 is connected the data output end of described angle sensor 3, the control output end of single-chip microcomputer 21 Be electrically connected with the signal input ends of two stepping motor drivers 19 respectively, the power input end of the power supply module 20 is connected with the positive and negative output ends of the vehicle power supply 18, and the power output end of the power supply module 20 is connected with the angle sensor 3 and the two respectively. Two stepper motor drivers 19 are electrically connected, and the output ends of the stepper motor drivers 19 are electrically connected to the power supply ports of the two stepper motors 6 respectively.

As a non-restrictive preference, the single-chip microcomputer 21 described in the utility model selects a PIC16F877A single-chip microcomputer, and the stepper motor driver 19 described in the utility model selects a model MB450A. The circuit connection of the electronic control unit 4 will be described in detail below in combination with the specific models of the single-chip microcomputer 21 and the stepper motor driver 19 .

As shown in Figure 10, the VDD interface of described angle sensor 3 is electrically connected with the 12V output terminal of power supply module 20, and the GND interface of angle sensor 3 is grounded, and the OUT interface of angle sensor 3 is a signal output port and is connected with the RA0 interface of single-chip microcomputer PIC16F877A connect. The VPP interface of the single-chip microcomputer PIC16F877A is a reset input interface, the VDD interface of the single-chip microcomputer PIC16F877A is electrically connected with the 5V output terminal of the power supply module, and the VSS interface of the single-chip microcomputer PIC16F877A is grounded.

As shown in Figure 11, the RC0 port of the single-chip microcomputer PIC16F877A is electrically connected to the positive terminal PUL+ port of the stepping pulse signal input of the two stepping motor drivers MB450A, and the RC1 port of the single-chip microcomputer PIC16F877A is connected to the negative terminal of the stepping pulse signal input of the stepping motor driver MB450A. The terminal PUL-port is electrically connected, and the RC0 and RC1 ports of the single-chip microcomputer PIC16F877A are responsible for sending pulse signals to the stepper motor driver 19 for controlling the rotation angle of the stepper motor 6 . The RC2 port of the single-chip microcomputer PIC16F877A is electrically connected with the stepping direction signal input positive terminal DIR+ port of the stepping motor driver MB450A, and the RC3 port of the single-chip microcomputer PIC16F877A is electrically connected with the stepping direction signal input negative terminal DIR- port of the stepping motor driver MB450A. The two ports RC2 and RC3 of PIC16F877A are responsible for sending the switching value to the stepping motor driver 19 for controlling the steering of the stepping motor 6 . The DC+ and DC- of the stepper motor driver MB450A are electrically connected to the 24V output terminal of the power supply module 20 and the ground terminal GND respectively, and are responsible for the power supply of the stepper motor driver 19 . The four ports A+, A-, B+, and B- of the stepper motor driver MB450A are respectively electrically connected to the corresponding stepper motor 6 power supply ports.

As shown in Figure 13, the single-chip microcomputer 21 of the electronic control unit 4 described in the utility model stores a pre-written electronically controlled steering follow-up wheel fender control program, and its execution steps are as follows:

1. Read the rotation angle signal A _SW measured by the rotation angle sensor 3 through the single-chip microcomputer 21, and calculate the steering wheel deflection angle A _fw according to the formula A _fw =A _sw /i. Among them, i represents the angular transmission ratio of the steering system, which can be selected in the range of 12-20 simply according to the different models of the car.

2. Determine whether the absolute value of the angle is greater than 5 degrees. If it is, it indicates that there is a certain steering angle, and there may be a danger of the tires stirring up stones and splashing. It is necessary to start the control and continue to the next step; otherwise, it is considered that the wheel rotation angle is too small. It is unlikely that the stones will splash, so return to the previous step and continue to read the signal of the corner sensor 3.

3. Continue to judge whether the absolute value of the steering wheel deflection angle A _fw is between 5-30 degrees, if yes, go to the next step; The possibility of stone splashing is small, and the deflection angle of the fender is controlled to be kept at the maximum value so as not to continue to increase with the increase of the wheel angle, that is, to enter step 5.

4. Continue to judge whether it is greater than positive 5 degrees or less than negative 5 degrees; if it is greater than positive 5 degrees, then according to the formula f=A _fw ×k, the single-chip microcomputer sends the frequency to the stepper motor driver 19 corresponding to the stepper motor 6 on the left wheel side The pulse of f is used to control the stepping motor 6 on the left wheel side to deflect clockwise for a fixed angle, that is, to deflect to the outside of the vehicle body _; The stepper motor driver 19 of the stepper motor 6 sends pulses with a frequency of f to control the stepper motor 6 on the right wheel side to deflect a fixed angle counterclockwise. Among them, the coefficient k is the conversion coefficient for converting the rotation angle into the frequency.

5. Continue to judge whether the angle is greater than positive 30 degrees; if so, send a pulse with a frequency of f to the stepper motor driver 19 corresponding to the stepper motor 6 on the left wheel side according to the formula f=30×k, so as to control the left wheel side Stepper motor 6 deflects the maximum angle clockwise; if not, according to the formula f=30×k, the stepper motor driver 19 that corresponds to the stepper motor 6 on the right wheel side sends a pulse with a frequency of f to control the right wheel side The stepper motor 6 deflects the maximum angle counterclockwise.

6. The ECU program ends.

The working principle of the electric control steering follower wheel fender device described in the utility model is as follows:

The rotation angle of the steering shaft 2 is measured by the rotation angle sensor 3, and the angular displacement signal is converted into an electrical signal and transmitted to the single-chip microcomputer 21, and the single-chip microcomputer 21 judges and processes the signal. When the absolute value of the angle is less than 5 degrees, the wheel rotation angle is very small, and the fender 5 itself can block the deflection of the wheel at a small angle to excite flying stones, and does not need to rotate with the direction. When the absolute value of the angle is between 5 degrees and 30 degrees, it is regarded as a large angle deflection of the wheel. Judging the turning direction of the steering shaft 2, it is stipulated that the clockwise rotation of the steering shaft 2 is positive, and the counterclockwise rotation is negative. When the angle is greater than 5 degrees, the rear side of the left wheel is obviously exposed to the car body, and the fender 5 needs to be rotated to block. This moment, right wheel rear side turns to in the car, does not need fender 5 to rotate. So when the angle is greater than 5 degrees, the signal is only delivered to the stepper motor driver 19 corresponding to the left wheel fender 5; It solves the problem of scratching the car body by the ordinary steering follow-up fender with the wheel steering. When the absolute value of the angle is greater than 30 degrees, it is regarded as a large angle deflection of the wheel. The limit rotation angle of the wheel is generally 35 degrees to 42 degrees. When the wheel rotation angle exceeds 30 degrees, the vehicle speed is low and it is not easy to cause the stones to splash at high speed. Therefore, the deflection angle of the fender 5 is kept at the deflection angle corresponding to 30 degrees, and does not increase with the wheels. deflection angle. As shown in FIG. 12 , it is a schematic diagram of the deflection working principle of the fender 5 .

Although the embodiment of the present utility model has been disclosed as above, it is not limited to the use listed in the description and the implementation, and it can be applied to various fields suitable for the present utility model. For those familiar with the art, Further modifications can be readily effected, so the invention is not limited to the specific details and examples shown and described herein without departing from the general concept defined by the claims and their equivalents.

Claims (8)

1. An electronically controlled steering follow-up wheel fender device is characterized in that it includes an electric control system, a stepping motor and a fender; At least two stepping motors are respectively mounted on the inner side of the wheel housing plate of the driving wheel of the automobile, and are used to receive the control signal of the electric control system and drive the two fenders to rotate respectively; At least two fenders are respectively installed on the output shaft of the stepping motor, and are deflected through the control of the stepping motor to effectively block the stones splashed by the rotating tire; The electronic control system includes a rotation angle sensor, an on-board power supply and an electronic control unit, wherein: A rotation angle sensor, installed on the steering shaft of the automobile, is used to detect the rotation angle of the steering wheel of the automobile and transmit the detection data to the electronic control unit; The electronic control unit is electrically connected with the rotation angle sensor and the stepping motor respectively, and is used for receiving the data transmitted by the rotation angle sensor and controlling the rotation of the stepping motor. 2. The electronic control steering follower wheel fender device according to claim 1, characterized in that: said stepper motors are respectively fixed on the inner side of said wheel house plate through a connecting plate and bolts, and on said wheel house A rectangular hole is provided on the board corresponding to the stepping motor, and is clearance-fitted with a rectangular housing corresponding to the output shaft side of the stepping motor. 3. The electronically controlled steering follower wheel fender device according to claim 2, characterized in that: the connecting plate is a rectangular flat plate with a through hole in the center, and two holes are respectively arranged around the through hole of the connecting plate. Connecting holes evenly distributed in circles are respectively used for connecting the stepping motor and the wheel cover plate. 4. The electric control steering follower wheel fender device according to claim 1, characterized in that: the fenders are respectively installed on the output shaft of the stepping motor through a spline shaft, and the fenders are formed by the upper end The handle, the lower end panel and the spline hub on the upper end of the upper handle constitute an integrated structure. The center of the spline hub is provided with a spline hole and matched with the spline shaft to facilitate installation and ensure reliable transmission. 5. The electronically controlled steering follower wheel fender device according to claim 4, characterized in that: the length of the spline hub in the axial direction is greater than the thickness of the upper end handle and the lower end panel, and its outer cylinder is twice as close to the upper end handle. The rounded corners of the side end face are smoothly transitioned to strengthen the local connection. 6. The electronic control steering follower wheel fender device according to claim 1, 4 or 5, characterized in that: the fender is a "knife" type injection molded by engineering plastics at one time and is concave as a whole panels to facilitate processing and reduce manufacturing costs. 7. The electronically controlled steering follow-up wheel fender device according to claim 1, characterized in that: said rotation angle sensor is installed in a protective shell, and is fixed on the steering shaft bracket of the automobile through the protective shell. 8. The electronically controlled steering wheel fender device according to claim 1 or 7, characterized in that: the electronic control unit includes a single-chip microcomputer, a power supply module and a stepping motor driver corresponding to the stepping motor respectively, and the single-chip microcomputer The input port is connected to the data output end of the angle sensor, the control output end of the single-chip microcomputer is electrically connected to the signal input end of the stepper motor driver, the power input end of the power module is connected to the vehicle power supply, and the power output ends of the power module are respectively It is electrically connected with the rotation angle sensor, the single chip microcomputer and the stepping motor driver, and the output terminals of the stepping motor driver are respectively electrically connected with the corresponding stepping motors.