CN111267824A - Automatic control method of automobile differential lock - Google Patents

Abstract

The invention discloses an automatic control method of an automobile differential lock, which comprises the following steps: an automatic opening method of an automobile differential lock and an automatic closing method of the automobile differential lock. The automatic control method of the automobile differential lock realizes the automatic opening and closing functions of the automobile differential lock through the control of the VCU controller, so that the vehicle can open and close the functions of the automobile differential lock accurately in time, the vehicle can run normally and safely, and the driving safety and the performance of the vehicle are ensured. The method compares the speed of the ABS system with the theoretical speed calculated by the TCU controller, and performs complementary substitution, so that the speed used in the control of the differential lock is more accurate and closer to the actual speed, the control precision of the differential lock is higher, the safety performance is better, the automatic opening and closing functions of the differential lock can be accurate and accurate, and the driving safety of the vehicle is ensured.

Description

A kind of automatic control method of automobile differential lock

technical field

The invention relates to the field of vehicle control, in particular to an automatic control method for a differential lock of an automobile.

Background technique

With the popularity of automobiles, people have higher and higher requirements for the performance of automobiles. Compared with the field of commercial vehicles, the requirements for the performance of automobiles are also increasing year by year, such as the safety performance of automobiles, and the performance of automobiles in poor road conditions. Therefore, the research on differential lock technology is becoming more and more important.

The differential can make the left and right (or front and rear) drive wheels rotate at different speeds. But when one of the wheels spins, the other wheel on good pavement doesn't get torque either and loses its driving momentum. Therefore, a car differential lock came into being, which can connect the two wheels when needed, and the power can be transmitted to the other wheel at least, so that the vehicle can get the driving power and get out of the predicament. However, the existing control of the differential lock is relatively simple and rough, and cannot automatically and efficiently enable the vehicle to turn on and off the differential lock function in a timely and accurate manner, and the safety performance of the vehicle is not well improved.

SUMMARY OF THE INVENTION

In order to solve the above technical problems, the main purpose of the present invention is to provide an automatic control method for the differential lock of an automobile.

In order to achieve the above object, the present invention adopts the following technical solutions to solve it.

An automatic control method for an automobile differential lock, comprising: an automatic opening method for an automobile differential lock, specifically:

Step 1, the VCU controller detects whether the differential lock switch is pressed, if the differential lock switch is pressed, execute step 2; otherwise, exit;

Step 2, the VCU controller receives the vehicle speed of the ABS front axle, and uses the TCU to calculate the theoretical vehicle speed; the VCU controller judges whether the ABS front axle vehicle speed is accurate, and determines the vehicle speed to be selected by the VCU controller; if the ABS front axle vehicle speed is judged to be accurate, then select The selected vehicle speed is the ABS front axle speed, otherwise, the selected vehicle speed is the theoretical vehicle speed;

Step 3, the VCU controller judges whether the selected vehicle speed is less than the first speed threshold; if the selected vehicle speed is less than the first speed threshold, then execute step 4, otherwise, exit;

Step 4: The enabling signal of the differential lock solenoid valve controlled by the VCU controller is all 1, and the differential lock back-check signal detected by the VCU controller is all 0, then the vehicle differential lock is unlocked, and the VCU controller sends the message in the form of a message. The differential lock open status is sent to the instrument and displayed.

Further, in step 1, the differential lock switch includes an inter-axle differential lock switch and a wheel differential lock switch, and at least one of the inter-axle differential lock switch and the wheel differential lock switch is pressed, then execute Step 2.

Further, in step 2, the specific method for judging whether the vehicle speed of the ABS front axle is accurate is as follows: subtract the theoretical vehicle speed from the vehicle speed of the ABS front axle, if the difference is less than 3km/h, then determine that the vehicle speed of the ABS front axle is accurate; Axle speed is inaccurate.

Further, in step 3, the first speed threshold is 5 km/h.

Further, in step 4, the differential lock solenoid valve includes an inter-axle differential lock solenoid valve and a wheel differential lock solenoid valve, and the differential lock check signal includes an inter-axle differential lock check signal, 3 Axle wheel differential lock back-check signal and 4-axle wheel differential lock signal;

When the inter-axle differential lock solenoid valve and the wheel differential lock solenoid valve enable signals are both 1, and the inter-axle differential lock check signal, the 3-axle wheel differential lock check signal, and the 4-axle wheel differential lock check signal When the lock signal is 0 at the same time, the vehicle differential lock is opened.

Further, it also includes an automatic closing method for the differential lock of the automobile, which is specifically:

Step 5, the VCU controller judges the differential lock check signal, if the differential lock check signal is all 0, then execute step 6, otherwise, exit;

Step 6, the VCU controller judges whether all the differential lock switches are reset, if at least one is not reset, execute step 7; if all are reset, otherwise, exit;

Step 7: The VCU receives the vehicle speed of the ABS front axle, and uses the TCU to calculate the theoretical vehicle speed; the VCU controller judges whether the ABS front axle vehicle speed is accurate, and determines the vehicle speed to be selected by the VCU controller; if the ABS front axle vehicle speed is judged to be accurate, the selected vehicle speed is the vehicle speed of the ABS front axle, otherwise, the selected vehicle speed is the theoretical vehicle speed;

Step 8, the VCU controller determines whether the selected vehicle speed is greater than the second speed threshold, if the selected vehicle speed is greater than the second speed threshold, execute step 9, otherwise, exit;

Step 9, the enabling signal of the differential lock solenoid valve controlled by the VCU controller is all 0, and the differential lock checkback signal detected by the VCU controller is all 1, then the vehicle differential lock is closed, and the VCU controller sends the message in the form of a message. The differential lock closed status is sent to the instrument and displayed.

Further, in step 5, the differential lock checkback signal includes an inter-axle differential lock checkback signal, a 3-axle wheel differential lock checkback signal, and a 4-axle wheel differential lock signal;

When the inter-axle differential lock check signal, the 3-axle wheel differential lock check signal and the 4-axle wheel differential lock signal are all 0 at the same time, go to step 6, otherwise, exit.

Further, in step 6, the differential lock switch includes an inter-axle differential lock switch and a wheel differential lock switch, and at least one of the inter-axle differential lock switch and the wheel differential lock switch is not reset, then perform step 6. 7; If all reset, control the differential lock solenoid valve enable to 0, exit.

Further, in step 8, the second speed threshold is 30 km/h.

Further, in step 9, the differential lock solenoid valve includes an inter-axle differential lock solenoid valve and a wheel differential lock solenoid valve, and the differential lock check signal includes an inter-axle differential lock check signal, 3 Axle wheel differential lock back-check signal and 4-axle wheel differential lock signal;

When the inter-axle differential lock solenoid valve and the wheel differential lock solenoid valve enable signals are both 0, and the inter-axle differential lock check signal, the 3-axle wheel differential lock check signal, and the 4-axle wheel differential lock check signal When the lock signal is 1 at the same time, the vehicle differential lock is closed.

The automatic control method of the vehicle differential lock of the present invention realizes the automatic opening and closing functions of the vehicle differential lock through the control of the VCU controller, so that the vehicle can timely and accurately open and close the differential lock function, so that the vehicle can run normally and safely. Guarantee the driving safety and performance of the vehicle. This method compares the vehicle speed of the ABS system with the vehicle speed calculated by the TCU controller, and replaces them with each other, so that the vehicle speed used in the differential lock control is more accurate, closer to the actual vehicle speed, and the differential lock control accuracy is higher. , The safety performance is better, so that the automatic opening and closing function of the differential lock can be precise and accurate, and the driving safety of the vehicle is guaranteed.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained according to the structures shown in these drawings without creative efforts.

Figure 1 is a part of the pin definition diagram of the VCU controller;

Figure 2 is another part of the pin definition diagram of the VCU controller

Fig. 3 is the flow chart of opening the differential lock of the automobile in the method of the present invention;

Fig. 4 is the flow chart of turning off the differential lock of the automobile in the method of the present invention;

In the picture above:

Pin B73 is the differential lock switch signal between axles;

Pin B74 is the wheel differential lock switch signal;

Pin B51 is the inter-axle differential lock check signal (normally closed);

The B52 pin is the 3-axle wheel differential lock back detection signal (normally closed);

The B54 pin is the 4-axle differential lock back detection signal (normally closed);

Pin B90 is the enable signal of the inter-axle differential lock solenoid valve;

Pin B91 is the enable signal of the wheel differential lock solenoid valve.

Detailed ways

In order to make the above objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

In the following description, specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar promotions without departing from the connotation of the present invention. Accordingly, the present invention is not limited by the specific embodiments disclosed below.

Referring to Figure 1, Figure 1 is a part of the pin definition diagram of the VCU controller, in which the B73 pin is the inter-axle differential lock switch signal, the B74 pin is the wheel differential lock switch signal, and the B51 pin is the inter-axle differential lock check signal ( Normally closed), the B52 pin is the 3-axle wheel differential lock checkback signal (normally closed), and the B54 pin is the 4-axle differential lock checkback signal (normally closed);

Figure 2 is another part of the pin definition diagram of the VCU controller, in which the B90 pin is the enable signal of the inter-axle differential lock solenoid valve, and the B91 pin is the wheel differential lock solenoid valve enable signal.

Referring to Figure 3, Figure 3 is a flow chart of the function of opening the differential lock of the car, and the automatic opening method of the differential lock of the car, specifically:

Step 1, the VCU controller judges the switch signal of pin B73 and pin B74, that is, the signal from the inter-axle differential lock switch and the wheel differential lock switch signal, if at least one of the inter-axle differential lock switch and the wheel differential lock switch is Press, that is, at least one of B73 signal or B74 signal is 1, then execute step 2; otherwise, exit;

Step 2, the VCU controller receives the vehicle speed of the ABS front axle, and uses the TCU to calculate the theoretical vehicle speed; wherein, the vehicle speed of the ABS front axle is the vehicle speed when the car adopts anti-lock braking; the TCU is the automatic transmission control unit, and the theoretical vehicle speed is calculated by the TCU obtained speed. The VCU controller judges whether the ABS front axle speed is accurate, and determines the vehicle speed to be selected by the VCU controller; the specific judgment method is: subtract the theoretical vehicle speed from the ABS front axle speed, if the difference is less than 3km/h, then judge the ABS front axle speed If it is accurate, the selected vehicle speed is the ABS front axle speed; if the difference is greater than or equal to 3km/h, the ABS front axle speed is judged to be inaccurate, and the selected vehicle speed is the theoretical vehicle speed.

Step 3, the VCU controller judges whether the selected vehicle speed is less than the first speed threshold 5km/h; if the selected vehicle speed is less than the first speed threshold 5km/h, then execute step 4, if the selected vehicle speed is greater than or equal to 5km/h, then exit ;

Step 4, the VCU controller controls the B91 inter-axle differential lock solenoid valve enable signal and the B92 wheel differential lock solenoid valve enable signal are both 1, and the VCU controller detects the B51 pin inter-axle differential lock back check signal, B52 pin 3 axle differential lock back-check signal and B53 pin 4 axle wheel differential lock signal are both 0, then the car differential lock is opened, and the VCU controller sends the differential lock open status in the form of a message to the instrument and display.

Referring to FIG. 4, FIG. 4 is a flowchart of the function of closing the differential lock of the automobile, and the automatic closing method of the differential lock of the automobile, specifically:

Step 5, the VCU controller judges that the differential lock check signal between the axles on the B51 pin, the wheel differential lock check signal on the B52 pin 3 axle and the wheel differential lock signal on the B53 pin 4 are all 0, then go to step 6, Otherwise, exit;

Step 6, the VCU controller judges the switch signal of pin B73 and pin B74, that is, the signal from the inter-axle differential lock switch and the wheel differential lock switch signal, if at least one of the inter-axle differential lock switch and the wheel differential lock switch is not Reset, that is, at least one of the B73 signal and the B74 signal is 0, then execute step 7; otherwise, exit;

Step 7, the VCU receives the vehicle speed of the ABS front axle, and uses the TCU to calculate the theoretical vehicle speed;

The VCU controller judges whether the ABS front axle speed is accurate, and determines the vehicle speed to be selected by the VCU controller; the specific judgment method is: subtract the theoretical vehicle speed from the ABS front axle speed, if the difference is less than 3km/h, then judge the ABS front axle speed If it is accurate, the selected vehicle speed is the ABS front axle speed; if the difference is greater than or equal to 3km/h, the ABS front axle speed is judged to be inaccurate, and the selected vehicle speed is the theoretical vehicle speed.

Step 8, the VCU controller judges whether the selected vehicle speed is greater than the second speed threshold 30km/h, if the selected vehicle speed is greater than the second speed threshold 30km/h, execute step 9, otherwise, exit;

Step 9, the VCU controller controls the B91 inter-axle differential lock solenoid valve enable signal and the B92 wheel differential lock solenoid valve enable signal are both 0, and the VCU controller detects the B51 pin inter-axle differential lock back check signal 、B52 pin 3 axle differential lock back check signal and B53 pin 4 axle wheel differential lock signal are both 1, then the car differential lock is closed, and the VCU controller sends the differential lock closed status in the form of a message to the meter and display.

Although the present invention has been described in detail with general description and specific embodiments in this specification, some modifications or improvements can be made on the basis of the present invention, which will be obvious to those skilled in the art. Therefore, these modifications or improvements made without departing from the present invention fall within the scope of the claimed protection of the present invention.

Claims (10)

1. An automatic control method of a vehicle differential lock is characterized by comprising the following steps: the automatic unlocking method of the automobile differential lock specifically comprises the following steps:

step 1, a VCU controller detects whether a differential lock switch is pressed down, and if the differential lock switch is pressed down, step 2 is executed; otherwise, quitting;

step 2, the VCU controller receives the ABS front axle vehicle speed, and the TCU is used for calculating to obtain a theoretical vehicle speed; the VCU controller judges whether the ABS front axle speed is accurate or not and determines the speed to be selected by the VCU controller; if the ABS front axle vehicle speed is judged to be accurate, the selected vehicle speed is the ABS front axle vehicle speed, otherwise, the selected vehicle speed is the theoretical vehicle speed;

step 3, the VCU controller judges whether the selected vehicle speed is less than a first speed threshold value; if the selected vehicle speed is less than the first speed threshold value, executing the step 4, otherwise, exiting;

and 4, controlling the enabling signal of the electromagnetic valve of the differential lock to be 1 by the VCU controller, detecting that the return detection signal of the differential lock is 0 by the VCU controller, finishing unlocking the automobile differential lock, and transmitting the unlocking state of the differential lock to an instrument and displaying by the VCU controller in a message form.

2. The automatic control method of a differential lock for a vehicle according to claim 1, wherein in step 1, the differential lock switch includes an inter-axle differential lock switch and a wheel-side differential lock switch, and when at least one of the inter-axle differential lock switch and the wheel-side differential lock switch is pressed, step 2 is performed.

3. The automatic control method of an automobile differential lock according to claim 1, wherein in the step 2, the specific method for judging whether the vehicle speed of the front axle of the ABS is accurate is as follows: and subtracting the theoretical speed from the ABS front axle speed, if the difference is less than 3km/h, judging that the ABS front axle speed is accurate, and otherwise, judging that the ABS front axle speed is inaccurate.

4. The automatic control method of a differential lock for a vehicle according to claim 1, wherein the first speed threshold value in step 3 is 5 km/h.

5. The automatic control method for a vehicle differential lock according to claim 1, wherein in step 4, the differential lock solenoid valves comprise an inter-axle differential lock solenoid valve and a wheel-side differential lock solenoid valve, and the differential lock return detection signals comprise an inter-axle differential lock return detection signal, a 3-axle wheel-side differential lock return detection signal and a 4-axle wheel-side differential lock signal;

when enabling signals of the inter-axle differential lock electromagnetic valve and the wheel-side differential lock electromagnetic valve are simultaneously 1, and the inter-axle differential lock return detection signal, the 3-axle wheel-side differential lock return detection signal and the 4-axle wheel-side differential lock signal are simultaneously 0, the opening of the automobile differential lock is completed.

6. The automatic control method of a vehicle differential lock according to claim 1, further comprising an automatic closing method of the vehicle differential lock, specifically:

step 5, the VCU controller judges the differential lock return detection signals, if the differential lock return detection signals are all 0, the step 6 is executed, otherwise, the operation is quitted;

step 6, the VCU controller judges whether the differential lock switches are all reset, if at least one of the differential lock switches is not reset, the step 7 is executed, and if not, the operation is quitted;

step 7, the VCU receives the ABS front axle vehicle speed, and the TCU is used for calculating to obtain a theoretical vehicle speed; the VCU controller judges whether the ABS front axle speed is accurate or not and determines the speed to be selected by the VCU controller; if the ABS front axle vehicle speed is judged to be accurate, the selected vehicle speed is the ABS front axle vehicle speed, otherwise, the selected vehicle speed is the theoretical vehicle speed;

step 8, the VCU controller judges whether the selected vehicle speed is greater than a second speed threshold value, if so, the step 9 is executed, otherwise, the operation is exited;

and 9, controlling the enabling signals of the electromagnetic valves of the differential lock to be 0 by the VCU controller, detecting that the return detection signals of the differential lock are 1 by the VCU controller, finishing closing the automobile differential lock, and sending the closing state of the differential lock to an instrument and displaying by the VCU controller in a message form.

7. The automatic control method for a vehicle differential lock according to claim 6, wherein in step 5, the differential lock return detection signal comprises an inter-axle differential lock return detection signal, a 3-axle wheel-side differential lock return detection signal and a 4-axle wheel-side differential lock signal;

and (6) when the inter-axle differential lock return detection signal, the 3-axle wheel-side differential lock return detection signal and the 4-axle wheel-side differential lock signal are simultaneously 0, executing the step, and otherwise, exiting.

8. The automatic control method of a differential lock for a vehicle according to claim 6, wherein in step 6, the differential lock switch includes an inter-axle differential lock switch and a wheel-side differential lock switch, and at least one of the inter-axle differential lock switch and the wheel-side differential lock switch is not reset, then step 7 is performed; if all the differential locks are reset, the electromagnetic valve of the differential lock is controlled to be enabled to be 0, and the differential lock exits.

9. The automatic control method of a differential lock for a vehicle according to claim 6, wherein the second speed threshold value is 30km/h in step 8.

10. The automatic control method for a vehicle differential lock according to claim 6, wherein in step 9, the differential lock solenoid valves comprise an inter-axle differential lock solenoid valve and a wheel-side differential lock solenoid valve, and the differential lock return detection signals comprise an inter-axle differential lock return detection signal, a 3-axle wheel-side differential lock return detection signal and a 4-axle wheel-side differential lock signal;

when enabling signals of the inter-axle differential lock electromagnetic valve and the wheel-side differential lock electromagnetic valve are simultaneously 0, and the inter-axle differential lock return detection signal, the 3-axle wheel-side differential lock return detection signal and the 4-axle wheel-side differential lock signal are simultaneously 1, closing of the automobile differential lock is completed.

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