CN116771827A - Walking control hydraulic system for silage machine and control method thereof - Google Patents

Abstract

This application discloses a travel control hydraulic system for silage machines and a control method thereof. The travel control hydraulic system for silage machines includes a variable plunger pump, an oil supply pump, a right front accumulator, a left front accumulator, and a left front one-way valve. , the right front check valve, the left front variable plunger motor, the rear axle variable plunger motor, the right front variable plunger motor, the variable plunger pump and the oil charge pump are drivingly connected to the power output device, and the A port of the variable plunger pump They are connected to port A of each motor respectively, and port B of the variable piston pump is connected to port B of each motor respectively; the output end of the oil charge pump is connected to port A and port of the left front variable piston motor through the left front one-way valve respectively. The A port of the right front variable plunger motor is connected through the right front one-way valve. The left front accumulator is bypassed to the input end of the left front one-way valve, and the right front accumulator is bypassed to the input end of the right front one-way valve. This application ensures the service life of hydraulic components, improves braking efficiency and braking accuracy, and reduces friction plate wear.

Description

A traveling control hydraulic system for silage machines and its control method

Technical field

The present application relates to the technical field of agricultural equipment, and in particular, to a traveling control hydraulic system for silage machines and a control method thereof.

Background technique

With the development of animal husbandry and the centralization of cattle and sheep breeding, farmers' demand for feed and storage capacity continue to increase, and the problem of manual harvesting and storage of forage is highlighted. After a long period of development and verification of agricultural mechanization, silage machines It plays an indispensable role in the harvesting, chopping, storage and transportation of forage; and with the rapid improvement of China's agricultural mechanization level in recent years, farmers' requirements for the automation level of agricultural machinery continue to increase. Therefore, the practicality of silage machines Safety and safety are particularly important; existing silage machine traveling systems generally use hydrostatic drive. In order to ensure the braking distance, most of them are equipped with mechanical braking devices. There are mainly the following methods in the braking process of this type of machinery: 1. One is to use the foot pedal to output pressure to perform friction braking on the driving mechanism; the second is a control method that combines friction braking and hydrostatic braking.

Regarding the existing braking technology, there are currently several shortcomings in the following aspects:

1. Mechanical braking and hydrostatic braking are independent of each other. No matter under deceleration or emergency braking conditions, the braking force is mainly output by stepping on the pedal and friction braking of moving parts. Frequent mechanical braking Friction accelerates the wear of components; and in the case of emergency braking, the handle does not return to the neutral position for some reasons, and the hydraulic system continues to output driving force. Pure mechanical braking greatly reduces the safety and reliability of braking;

2. Some machines use a combination of mechanical braking and hydrostatic braking, but the pump and motor variables are mainly controlled by the pressure feedback of the foot pedal. When the foot pedal is lightly pressed to decelerate, the pressure signal controls the pump and motor variable displacement. The amount will inevitably coexist with friction braking during the hydrostatic braking process. This control method not only accelerates the wear of the friction plates, but also easily confuses the two working conditions of deceleration and emergency braking, reducing the braking accuracy of the entire machine. braking efficiency;

3. The hydrostatic braking power mainly comes from the high-pressure and low-pressure conversion at the inlet and outlet of the hydraulic motor, forming a reverse braking force. Under high-speed emergency braking conditions of the vehicle, it will cause an instantaneous ultra-high pressure at the motor oil outlet (low-pressure port). Due to the limitations of the flow rate of the high-pressure relief valve inside the closed pump and the flow rate of the charge pump, the high-pressure oil on the brake side cannot be instantly replenished to the low-pressure side, which results in an instantaneous loss of pressure at the motor oil inlet and an instantaneous loss of pressure at the outlet of the charge pump. This sudden loss of pressure can easily lead to the failure of hydraulic components such as variable pumps and variable motors, affecting their service life.

Contents of the invention

On the one hand, embodiments of the present application provide a traveling control hydraulic system for silage machines to solve the technical problem of short service life of hydraulic components in the prior art.

The technical solutions adopted in the embodiments of this application are as follows:

A traveling control hydraulic system for a silage machine, including a variable plunger pump, an oil charge pump, a right front accumulator, a left front accumulator, a left front check valve, a right front check valve, a left front variable plunger motor, and a rear axle variable plunger. Motor, right front variable piston motor, where:

The variable piston pump and the oil charge pump are drivingly connected to the power output device. The A port of the variable piston pump is respectively connected to the A port of the left front variable piston motor, the rear axle variable piston motor, and the right front variable piston motor. , the B port of the variable piston pump is connected to the B port of the left front variable piston motor, the rear axle variable piston motor, and the right front variable piston motor; the output end of the charge pump is connected through the left front one-way valve. Port A of the left front variable piston motor is connected to port A of the right front variable piston motor through the right front one-way valve. The left front accumulator is bypassed at the input end of the left front one-way valve, and the right front accumulator is bypassed at the right front single check valve. to the input end of the valve.

Preferably, it also includes a second relief valve and two first relief valves. The two first relief valves are connected in series and then in parallel and are arranged between ports A and B of the variable displacement piston pump; the second relief valve The relief valve is connected to the output end of the charge pump.

Preferably, it also includes a one-way valve, the output end of the one-way valve is connected to the output end of the oil charge pump, and the input end of the one-way valve is connected to the right front accumulator and the left front accumulator respectively.

Preferably, a third relief valve is further included, and the third relief valve is bypassed at the input end of the one-way valve.

Preferably, it also includes a first pressure sensor and a second pressure sensor. The first pressure sensor is connected to the output end of the oil charge pump and is used to detect the outlet pressure of the oil charge pump; the second pressure sensor is bypassed. The pipeline between the one-way valve and the right front accumulator and the left front accumulator is used to detect the pressure in the right front accumulator and the left front accumulator.

On the other hand, this application provides a control method for a hydraulic system for traveling control of a silage machine to solve the technical problems of low braking efficiency, low braking accuracy, and rapid friction plate wear in the prior art.

The technical solutions adopted in the embodiments of this application are as follows:

A control method for a traveling control hydraulic system of a silage machine, including the steps:

Get the current pedal pedaling angle;

According to the range of the actual pedaling angle, the displacement of the variable piston pump, the left front variable piston motor, the rear axle variable piston motor, and the right front variable piston motor are controlled according to the corresponding displacement change slope to output a corresponding size of static pressure. The hydraulic braking force realizes the gradual deceleration of the vehicle; and only after the actual pedaling angle reaches the set threshold, while outputting the corresponding hydrostatic braking force, the foot brake valve output is also driven according to the actual pedaling angle. The hydraulic pressure reaches the brake caliper to generate a corresponding friction braking force to realize emergency braking of the vehicle, wherein the displacement change slope and the hydraulic pressure output by the foot brake valve are positively related to the actual pedaling angle.

Further, the displacement of the variable piston pump, the left front variable piston motor, the rear axle variable piston motor, and the right front variable piston motor is controlled according to the corresponding displacement change slope according to the interval where the actual pedaling angle is. Output a corresponding amount of hydrostatic force to achieve gradual deceleration of the vehicle; and only after the actual pedaling angle reaches the set threshold, while outputting a corresponding amount of hydrostatic force, also according to the actual pedaling angle. Drive the foot brake valve to output hydraulic pressure to the brake caliper to generate a corresponding friction braking force to achieve emergency braking of the vehicle. The specific steps include:

If the current stepping angle of the pedal θ<θ ₀ , the vehicle is in a normal driving state by default. At this time, the vehicle's driving speed is controlled by the handle, and the control system close-loop controls the vehicle speed and the handle current value to match each other;

If the current pedaling angle θ ₀ ≤ θ ≤ _{θ 1} , the control system overrides the handle control and controls the variable piston pump, left front variable piston motor, rear axle variable piston motor, and right front with the first displacement change slope K _θX1 The displacement of the variable piston motor is used to output a corresponding amount of hydrostatic power to achieve gradual vehicle deceleration;

If the current pedal angle θ ₁ <θ ≤ θ ₂ , the control system overrides the handle control and uses the second displacement change slope K _θX2 to control the variable piston pump, left front variable piston motor, rear axle variable piston motor, and right front The displacement of the plunger motor is variable to output a corresponding amount of hydrostatic force, where K _θX1 <K _θX2 ; at the same time, the foot brake valve outputs hydraulic pressure based on the actual pedaling angle to act on the brake caliper to generate a corresponding amount of friction. The braking force realizes emergency braking of the vehicle, and the friction braking force is positively related to the actual pedaling angle.

Further, the first displacement change slope K _θX1 and the second displacement change slope K _θX2 are specifically:

_{Among them : θ _} Slope; k ₀ and k ₁ are the displacement change slope of the pump and motor displacement that need to be controlled when decelerating when the pedal pedaling angle is θ ₀ and θ ₁ respectively; θ _X2 is the pedal pedaling angle at (θ ₁ , θ ₂ ] The real _- time feedback value within _{the interval} , _K θ It is necessary to control the displacement change slope of pump and motor displacement changes.

Further, if the current pedal angle θ ₀ ≤ θ ≤ θ ₁ , the control system overrides the handle control and controls the variable plunger pump, left front variable plunger motor, and rear axle variable with the first displacement change slope K _θX1 The displacement of the plunger motor and the right front variable plunger motor is used to output a corresponding amount of hydrostatic power to achieve gradual vehicle deceleration. The specific steps include:

If the motor current I _m =0, each motor is at its maximum displacement and the hydraulic system is in a pump speed regulation state. At this time, the variable plunger pump is controlled with the first displacement change slope K _θX1 to reduce the pump displacement until the vehicle decelerates. to 0;

If the motor current I _m ≠ 0, the hydraulic system is in the state of maximum pump displacement and motor variable displacement speed regulation. At this time, the first displacement change slope K θX1 is used to control each motor to increase to the maximum displacement, and then the third displacement change slope K _θX1 is used to control each motor to increase to the maximum displacement. A displacement change slope K _θX1 controls the variable displacement piston pump to reduce the pump displacement until the vehicle decelerates to 0.

Further, if the current pedaling angle θ ₁ <θ ≤ θ ₂ is stated, the control system overrides the handle control and controls the variable piston pump, left front variable piston motor, and rear axle variable with the second displacement change slope K _θX2 The displacement of the plunger motor and the right front variable plunger motor is used to output a corresponding amount of hydrostatic power to achieve gradual vehicle deceleration. The specific steps include:

If the motor current I _m =0, each motor is at its maximum displacement and the hydraulic system is in a pump speed regulation state. At this time, the variable plunger pump is controlled with the second displacement change slope K _θX2 to reduce the pump displacement until the vehicle decelerates. to 0;

If the motor current I _m ≠ 0, the hydraulic system is in a state of maximum pump displacement and motor variable displacement speed regulation. At this time, the second displacement change slope K _θX2 is used to simultaneously control each motor to increase displacement and the variable piston pump. Reduce pump displacement until the vehicle decelerates to 0;

or,

If the motor current I _m ≠ 0, the hydraulic system is in the state of maximum pump displacement and motor variable displacement speed regulation. At this time, the second displacement change slope K θX2 is first used to control each motor to increase to the maximum displacement, and then the second displacement change slope K _θX2 is used to control each motor to increase to the maximum displacement. The second displacement change slope K _θX2 controls the variable displacement piston pump to reduce the pump displacement until the vehicle decelerates to 0.

Compared with the existing technology, this application has the following beneficial effects:

This application provides a travel control hydraulic system for silage machines and a control method thereof. The travel control hydraulic system for silage machines aims at the problem of instantaneous pressure loss at the original high-pressure port of a closed system caused by high-speed emergency braking of vehicles. Set up an accumulator and one-way valve for oil replenishment to quickly replenish the oil to the pressure loss side, avoiding the failure of the variable pump and variable motor, ensuring the service life of the hydraulic components, and using a smaller number of commonly used components to achieve silage The demand for vehicle deceleration and emergency braking; the control method uses the optimized design of the control logic to differentially control the vehicle's pure deceleration condition and emergency braking condition: for example, in the pure deceleration condition, the system hydrostatic pressure is used Braking; in emergency braking conditions, the system hydrostatic braking + friction braking is used to avoid the problem of premature damage to the friction plates caused by a large number of friction braking, and increases the service life of the components; emergency braking In this case, if the handle does not return to the neutral position for some reason, the hydraulic system will continue to output driving force. At this time, only friction braking by the foot brake will cause the braking distance to be greatly increased. The control method of this application is in obtaining the current The control method is controlled according to the actual pedaling angle according to the positively related displacement change slope according to the range of the actual pedaling angle, which avoids the occurrence of this situation and improves the safety and reliability of the whole machine braking. The displacement of the pump and motor is used to output a corresponding amount of hydrostatic force. That is, the smaller the actual pedaling angle is, the smaller the displacement change slope is used to control the displacement of each pump and motor to output a smaller hydrostatic force. To realize the gradual deceleration of the vehicle, the larger the actual pedaling angle is, the displacement of each pump and motor is controlled with a larger displacement change slope to output greater hydrostatic braking force, and at the same time, the hydraulic pressure is also output to the brake caliper to produce a greater The large friction braking force jointly realizes emergency braking of the vehicle, that is, this application can output different sizes and types of braking force according to different working conditions, thus greatly improving the braking accuracy and braking efficiency of the entire machine.

The present application provides other objects, features and advantages in addition to those described above. The present application will be described in further detail below with reference to the accompanying drawings.

Description of drawings

The drawings that form a part of this application are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an improper limitation of this application. In the attached picture:

Figure 1 is a schematic diagram of the structural principle of the travel control hydraulic system for the silage machine of the present application.

Figure 2 is a schematic flowchart of the control method according to the preferred embodiment of the present application.

Figure 3 is a schematic diagram of the relationship between the pedal angle signal and the output hydraulic pressure of the foot brake valve according to the preferred embodiment of the present application.

Figure 4 is a schematic diagram of the relationship between the pedal angle signal and the displacement change slope according to the preferred embodiment of the present application.

Figure 5 is a schematic diagram of the relationship between the pedal angle signal and vehicle braking force according to the preferred embodiment of the present application.

Figure 6 is a schematic diagram of a control device module according to a preferred embodiment of the present application.

Figure 7 is a physical diagram of an electronic device according to a preferred embodiment of the present application.

Figure 8 is a schematic diagram of the composition of computer equipment according to a preferred embodiment of the present application.

Shown in the figure: 1. Variable plunger pump; 2. Charge pump; 3. First relief valve; 4. Second relief valve; 5. First pressure sensor; 6. Third relief valve; 7. Check valve; 8.1, right front accumulator; 8.2, left front accumulator; 9.2, left front check valve; 9.1, right front check valve; 10, left front variable plunger motor; 11, rear axle variable plunger motor; 12 , Right front variable plunger motor; 13. Second pressure sensor.

Detailed ways

It should be noted that, as long as there is no conflict, the embodiments and features in the embodiments of this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and embodiments.

As shown in Figure 1, the preferred embodiment of the present application provides a travel control hydraulic system for silage machines, including a variable plunger pump 1, an oil charge pump 2, a right front accumulator 8.1, a left front accumulator 8.2, and a left front one-way Valve 9.2, right front one-way valve 9.1, left front variable plunger motor 10, rear axle variable plunger motor 11, right front variable plunger motor 12, among which:

The variable piston pump 1 and the oil charge pump 2 are drivingly connected to the power output device. Port A of the variable piston pump 1 is connected to the left front variable piston motor 10, the rear axle variable piston motor 11, and the right front variable piston motor respectively. 12 is connected to port A, and port B of the variable piston pump 1 is connected to port B of the left front variable piston motor 10, the rear axle variable piston motor 11, and the right front variable piston motor 12 respectively; the oil charge pump The output ends of 2 are respectively connected to the A port of the left front variable plunger motor 10 through the left front one-way valve 9.2, and to the A port of the right front variable plunger motor 12 through the right front one-way valve 9.1. The left front accumulator 8.2 is bypassed at the left front The input end of the one-way valve 9.2, the right front accumulator 8.1 is bypassed to the input end of the right front one-way valve 9.1.

Preferably, the hydraulic system for traveling control of the silage machine also includes a second relief valve 4 and two first relief valves 3. The two first relief valves 3 are connected in series and then installed in parallel on the variable displacement piston pump 1. Between port A and port B; the second relief valve 4 is connected to the output end of the charge pump 2 .

Preferably, the hydraulic system for traveling control of the silage machine also includes a one-way valve 7, the output end of the one-way valve 7 is connected to the output end of the oil charge pump 2, and the input end of the one-way valve 7 is connected to the right front pump respectively. Accumulator 8.1, left front accumulator 8.2.

Preferably, the hydraulic system for traveling control of the silage machine further includes a third relief valve 6 , and the third relief valve 6 is bypassed at the input end of the one-way valve 7 .

Preferably, the hydraulic system for traveling control of the silage machine also includes a first pressure sensor 5 and a second pressure sensor 13. The first pressure sensor 5 is connected to the output end of the oil charge pump 2 for detecting the The outlet pressure of the charge pump 2; the second pressure sensor 13 is bypassed on the pipeline between the one-way valve 7 and the right front accumulator 8.1 and the left front accumulator 8.2, and is used to detect the right front accumulator 8.1 and the left front accumulator 8.1. Pressure in accumulator 8.2.

In the above embodiment, the variable piston pump 1 is the power source of the hydraulic travel system, and the swash plate can be variable in both directions; the oil supply pump 2 is a gear pump. In this hydraulic system, the main function of the oil in the oil supply pump 2 is: low pressure of the hydraulic system Side oil replenishment, motor housing flushing, control of variable plunger pump 1 swash plate variable; the first relief valve 3 is a high-pressure relief valve, its main function is when the oil pressure on one side of the hydraulic system is higher than the relief valve setting When the value is reached, the first relief valve 3 opens, the high-pressure side oil enters the low-pressure side, and the oil in the pump inlet and outlet circulates; the second relief valve 4 is a charge relief valve, controlling the outlet pressure of the charge pump; The first pressure sensor 5 is a charge pressure sensor that detects the outlet pressure of the charge pump 2 at all times;

The third relief valve 6 is a safety valve. If the leakage of the right front one-way valve 9.1 or the left front one-way valve 9.2 is relatively large, long-term walking will cause the high-pressure side oil to pass through the right front one-way valve 9.1 or the left front one-way valve. 9.2 leaks between the one-way valve 7 and the right front accumulator 8.1 or the left front accumulator 8.2, causing the pressure of each accumulator to continuously increase. If there is a problem with the right front one-way valve 9.1 or the left front one-way valve 9.2, the high-pressure side will Oil can directly enter each accumulator. Therefore, when the pressure increases to the set pressure of the third relief valve 6, the third relief valve 6 unloads, protecting each accumulator and improving the use of each accumulator. safety and reliability; the one-way valve 7 is a one-way stop valve. Under high-speed emergency braking conditions, due to the limitations of the 3-way flow of the first relief valve and the flow of the oil charge pump 2, the left front variable plunger motor 10, The inlet A of the right front variable piston motor 12 will lose pressure, and the oil stored in each accumulator will be quickly replenished to the pressure loss side. However, at the same time, the outlet pressure of the oil charge pump 2 will also decrease. In order to ensure that each accumulator All the internally stored oil quickly enters the left front variable piston motor 10 and the right front variable piston motor 12 without flowing back to the charge pump 2 side. This application sets a one-way valve 7 for reverse cutoff. Under normal working conditions, the charge pump 2. Supply oil to each accumulator in the positive direction through the one-way valve 7;

The right front one-way valve 9.1 or the left front one-way valve 9.2 is a one-way stop valve, which reversely blocks the imported high-pressure oil of the left front variable piston motor 10 and the right front variable piston motor 12. The left front variable piston motor 10 and the right front variable piston motor 12 When the oil inlet loses pressure, the oil in the right front accumulator 8.1 or the left front accumulator 8.2 is quickly replenished to the left front variable plunger motor 10 and the right front variable plunger through the right front one-way valve 9.1 or the left front one-way valve 9.2 respectively. Low voltage side of motor 12;

The left front variable piston motor 10 and the right front variable piston motor 12 are front axle left and right wheel drive motors, and the rear axle variable piston motor 11 is a rear axle drive motor. Each motor is a variable displacement motor. The left front variable piston motor 10 , the right front variable plunger motor 12 has the maximum displacement when power is lost. Since high-speed emergency braking usually occurs in two-wheel drive (front-wheel drive) mode, the oil replenishment of each accumulator is only set on the oil circuit of the left and right front traveling motors. .

The second pressure sensor 13 is arranged on the pipeline between each accumulator and the one-way valve 7. The second pressure sensor 13 can provide a safety alarm in advance. The alarm pressure of the second pressure sensor 13 is greater than the oil supply pressure. , is slightly less than the set pressure of the third relief valve 6. When the right front one-way valve 9.1 or the left front one-way valve 9.2 has a relatively large leakage or other problems, the pressure of each accumulator continues to increase and reaches the point where the second pressure sensor 13 alarms. When the pressure is high, the system prompts that the pressure of each accumulator is too high and needs to be inspected.

It can be seen that the travel control hydraulic system for silage machines provided by the above embodiments is aimed at the problem of instantaneous pressure loss at the original high-pressure port of the closed system caused by high-speed emergency braking of the vehicle. By setting an accumulator and a one-way valve for oil replenishment in the circuit, the system can The oil is quickly replenished to the pressure loss side, avoiding the failure of the variable pump and variable motor, ensuring the service life of the hydraulic components, and using a smaller number of commonly used components to achieve the needs of deceleration and emergency braking of the silage machine;

As shown in Figure 2, another preferred embodiment of the present application provides a control method for a traveling control hydraulic system for a silage machine, including the steps:

S1. Obtain the current pedaling angle, for example, set an angle sensor on the pedal, and use the angle sensor to detect the current pedaling angle in real time;

S2. Control the displacement of the variable piston pump 1, the left front variable piston motor 10, the rear axle variable piston motor 11, and the right front variable piston motor 12 according to the corresponding displacement change slope according to the range of the actual pedaling angle. The vehicle is gradually decelerated by outputting a corresponding amount of hydrostatic force; and only after the actual pedaling angle reaches the set threshold, while outputting a corresponding amount of hydrostatic force, the vehicle is also decelerated according to the actual pedaling angle. The large and small drive foot brake valve outputs hydraulic pressure to the brake caliper to generate a corresponding friction braking force to implement emergency braking of the vehicle. The displacement change slope and the hydraulic pressure output by the foot brake valve are positively related to the actual pedaling angle.

The control method provided by this embodiment uses the optimized design of the control logic to differentially control the vehicle's pure deceleration conditions and emergency braking conditions: for example, in pure deceleration conditions, system hydrostatic braking is used; while in emergency braking conditions, During dynamic working conditions, system hydrostatic braking + friction braking is used to avoid the problem of premature damage to the friction plates caused by a large amount of friction braking, and increases the service life of the components; in the case of emergency braking, if due to some The reason is that the handle has not returned to the neutral position, and the hydraulic system will continue to output driving force. At this time, only friction braking by the foot brake will cause the braking distance to be greatly increased. The control method of this application overrides the control after obtaining the current pedal pedal angle. , avoiding the occurrence of this situation and improving the safety and reliability of the whole machine braking; the control method of this embodiment controls the displacement of each pump and motor according to the positively correlated displacement change slope according to the range of the actual pedaling angle. To output a corresponding amount of hydrostatic force, that is, the smaller the actual pedaling angle is, the smaller the displacement change slope is used to control the displacement of each pump and motor to output a smaller hydrostatic force to achieve a gradual deceleration of the vehicle. The larger the actual pedaling angle is, the larger the displacement change slope is used to control the displacement of each pump and motor to output greater hydrostatic braking force. At the same time, it also outputs hydraulic pressure to the brake caliper to generate greater friction braking force. To realize vehicle emergency braking, this application can output different sizes and types of braking force according to different working conditions, thus greatly improving the braking accuracy and braking efficiency of the entire machine.

Preferably, the variable piston pump 1, the left front variable piston motor 10, the rear axle variable piston motor 11, and the right front variable piston motor 12 are controlled according to the corresponding displacement change slope according to the actual pedaling angle. The displacement is to output a hydrostatic force of a corresponding size to realize the vehicle's gradual deceleration; and only after the actual pedaling angle reaches the set threshold, while outputting a hydrostatic force of a corresponding size, the vehicle is also decelerated according to the actual pedaling angle. The size of the pedaling angle drives the foot brake valve to output hydraulic pressure to the brake caliper to generate a corresponding friction braking force to achieve emergency braking of the vehicle. The specific steps include:

S21. If the current stepping angle of the pedal is θ<θ ₀ , the vehicle is in a normal driving state by default. At this time, the vehicle's driving speed is controlled by the handle, and the closed-loop control system controls the vehicle speed and the handle current value to match each other;

S22. If the current pedal angle θ ₀ ≤ θ ≤ θ ₁ , the control system overrides the handle control and controls the variable plunger pump 1, the left front variable plunger motor 10, and the rear axle variable column with the first displacement change slope K _θX1 The displacement of the piston motor 11 and the right front variable piston motor 12 is used to output a corresponding amount of hydrostatic power to achieve gradual vehicle deceleration;

S23. If the current pedal angle θ ₁ <θ ≤ θ ₂ , the control system overrides the handle control and uses the second displacement change slope K _θX2 to control the variable piston pump 1, the left front variable piston motor 10, and the rear axle variable column. The displacements of the piston motor 11 and the right front variable piston motor 12 are used to output corresponding hydrostatic pressing power, where K _θX1 <K _θX2 ; at the same time, the foot brake valve outputs hydraulic pressure to act on the brake according to the actual pedaling angle. The caliper generates a corresponding friction braking force to implement emergency braking of the vehicle, and the friction braking force is positively related to the actual pedaling angle.

As shown in Figure 3, the foot pedal is connected to the angle sensor. The abscissa is the actual pedaling angle, which corresponds to the angle sensor feedback electrical signal and the angle brake valve output pressure respectively. The interval 0 to θ ₀ is set as the dead zone. This interval When there is a slight change in the pedaling angle of the inner pedal, it will not cause the angle sensor to output an electrical signal, which can avoid misoperation caused by some external environments and human factors. Within the interval θ ₀ ~ θ ₁ , the angle sensor outputs an electrical signal corresponding to 0 ~ I1. This When the pedal has no pressure, the oil is output to the brake caliper; within the interval θ ₁ to θ ₂ , the angle sensor outputs an electrical signal corresponding to I1-I2. At this time, the pedal output pressure range is 0 to P _max . It can be seen that in this embodiment, the pedal The output pressure and angle sensor signals are positively related to the pedal angle.

As shown in Figure 4, when the controller detects the electrical signal fed back by the angle sensor, it overrides the handle control. When the angle signal is within the interval θ ₀ ~ θ ₁ , the system defaults to the slow deceleration condition, and the system decelerates at a lower slope. Control the pump and motor variables (motor increases displacement, pump decreases displacement), and the displacement change slope is set to the first displacement change slope K _θX1 , as shown in Figure 5. The whole machine brake is hydrostatic in this interval. Braking, the braking force is in the range 0~F1. Under this working condition, only hydrostatic braking is used to achieve slow deceleration, which avoids rapid wear of the friction plates caused by repeated mechanical friction braking.

As shown in Figure 4, when the angle signal is within the interval θ ₁ ~ θ ₂ , the system defaults to the emergency braking condition and needs to decelerate and stop quickly. The system controls the pump and motor variables at a higher slope (the motor increases displacement, (pump reduces displacement), the displacement change slope is set to the second displacement change slope K _θ It also increases with the increase of the pedaling angle, which acts on the brake caliper to generate friction braking force. As shown in Figure 5, the whole machine braking in the interval θ ₁ to θ ₂ includes hydrostatic braking + mechanical friction braking. The power is in the range F1~F2, and the vehicle braking force F is larger, realizing a rapid emergency stop of the vehicle.

Specifically, the first displacement change slope K _θX1 and the second displacement change slope K _θX2 are:

_{Among them : θ _} Slope; k ₀ and k ₁ are the displacement change slope of the pump and motor displacement that need to be controlled when decelerating when the pedal pedaling angle is θ ₀ and θ ₁ respectively; θ _X2 is the pedal pedaling angle at (θ ₁ , θ ₂ ] The real _- time feedback value within the _{interval , K} θ It is necessary to control the displacement change slope of pump and motor displacement changes.

Preferably, if the current pedal angle θ ₀ ≤ θ ≤ θ ₁ , the control system overrides the handle control and controls the variable piston pump 1 , the left front variable piston motor 10 , and the rear variable piston pump 1 with the first displacement change slope K _θX1 The displacement of the bridge variable piston motor 11 and the right front variable piston motor 12 is used to output a corresponding amount of hydrostatic power to achieve gradual deceleration of the vehicle. The specific steps include:

S221. If the motor current I _m =0, each motor is at the maximum displacement and the hydraulic system is in the pump speed regulation state. At this time, the variable plunger pump 1 is controlled to reduce the pump displacement with the first displacement change slope K _θX1 . Until the vehicle decelerates to 0;

S222. If the motor current I _m ≠ 0, the hydraulic system is in the state of maximum pump displacement and motor variable displacement speed regulation. At this time, the first displacement change slope K _θX1 is used to control each motor to increase to the maximum displacement, and then The variable displacement piston pump 1 is controlled with a first displacement change slope K _θX1 to reduce the pump displacement until the vehicle decelerates to 0.

Preferably, if the current stepping angle of the pedal is θ ₁ <θ ≤ θ ₂ , the control system overrides the handle control and controls the variable piston pump 1 , left front variable piston motor 10 , and rear with the second displacement change slope K _θX2 The displacement of the bridge variable piston motor 11 and the right front variable piston motor 12 is used to output a corresponding amount of hydrostatic power to achieve gradual deceleration of the vehicle. The specific steps include:

S2301. If the motor current I _m =0, each motor is at the maximum displacement and the hydraulic system is in the pump speed regulation state. At this time, the variable plunger pump 1 is controlled to reduce the pump displacement with the second displacement change slope K _θX2 . Until the vehicle decelerates to 0;

S2302. If the motor current I _m ≠ 0, the hydraulic system is in the state of maximum pump displacement and motor variable displacement speed regulation. At this time, the second displacement change slope K _θX2 is used to simultaneously control each motor to increase displacement and the variable column. Plug pump 1 to reduce pump displacement until the vehicle decelerates to 0.

Preferably, if the current stepping angle of the pedal is θ ₁ <θ ≤ θ ₂ , the control system overrides the handle control and controls the variable piston pump 1 , left front variable piston motor 10 , and rear with the second displacement change slope K _θX2 The displacement of the bridge variable piston motor 11 and the right front variable piston motor 12 is used to output a corresponding amount of hydrostatic power to achieve gradual deceleration of the vehicle. The specific steps include:

S2311. If the motor current I _m =0, each motor is at the maximum displacement and the hydraulic system is in the pump speed regulation state. At this time, the variable plunger pump 1 is controlled to reduce the pump displacement with the second displacement change slope K _θX2 . Until the vehicle decelerates to 0;

S2312. If the motor current I _m ≠0, the hydraulic system is in the maximum displacement state of the pump and variable displacement speed regulation of the motor. At this time, the second displacement change slope K _θX2 is used to control each motor to increase to the maximum displacement, and then The variable displacement piston pump 1 is controlled with a second displacement change slope K _θX2 to reduce the pump displacement until the vehicle decelerates to 0.

As shown in Figure 6, the preferred embodiment of the present application also provides a control device for the traveling control hydraulic system of the silage machine, including:

Pedaling angle acquisition module, used to obtain the current pedaling angle;

The braking force control module is used to control the variable plunger pump 1, the left front variable plunger motor 10, the rear axle variable plunger motor 11, and the right front variable plunger according to the corresponding displacement change slope according to the range of the actual pedaling angle. The displacement of the motor 12 is such that it can output a hydrostatic force of a corresponding size to achieve gradual deceleration of the vehicle; and only after the actual pedaling angle reaches the set threshold, while outputting a hydrostatic force of a corresponding size, the vehicle is also decelerated according to the required amount. The actual pedaling angle drives the foot brake valve to output hydraulic pressure to the brake caliper to generate a corresponding friction braking force to achieve emergency braking of the vehicle. The displacement change slope, the hydraulic pressure output by the footbrake valve and the actual pedaling angle are The size is positively related.

As shown in Figure 7, a preferred embodiment of the present application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program Steps to implement the control method of the hydraulic system for traveling control of the silage machine in the above embodiment.

As shown in Figure 8, a preferred embodiment of the present application also provides a computer device. The computer device can be a terminal or a living body detection server, and its internal structure diagram can be shown in Figure 8. The computer device includes a processor, memory, and network interfaces connected through a system bus. Wherein, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes non-volatile storage media and internal memory. The non-volatile storage medium stores operating systems and computer programs. This internal memory provides an environment for the execution of operating systems and computer programs in non-volatile storage media. The network interface of the computer device is used to communicate with other external computer devices through a network connection. When the computer program is executed by the processor, the steps of the control method of the hydraulic system for traveling control of the silage machine are implemented.

Those skilled in the art can understand that the structure shown in Figure 8 is only a block diagram of a partial structure related to the solution of the present application, and does not constitute a limitation on the computer equipment to which the solution of the present application is applied. Specific computer equipment can May include more or fewer parts than shown, or combine certain parts, or have a different arrangement of parts.

A preferred embodiment of the present application also provides a storage medium. The storage medium includes a stored program. When the program is running, the device where the storage medium is located is controlled to execute the hydraulic system for traveling control of the silage machine in the above embodiment. steps of the control method.

It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and, although a logical sequence is shown in the flowchart, in some cases, The steps shown or described may be performed in a different order than here.

If the functions described in the method of this embodiment are implemented in the form of software functional units and sold or used as independent products, they can be stored in one or more computing device-readable storage media. Based on this understanding, the part that the embodiments of the present application contribute to the prior art or the part of the technical solution can be embodied in the form of a software product. The software product is stored in a storage medium and includes a number of instructions to enable a A computing device (which may be a personal computer, a server, a mobile computing device or a network device, etc.) executes all or part of the steps of the methods described in various embodiments of this application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disks or optical disks and other media that can store program codes. .

Those skilled in the art will understand that embodiments of the present application may be provided as methods, systems, or computer program products. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment that combines software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein. The solutions in the embodiments of this application can be implemented using various computer languages, such as the object-oriented programming language Java and the literal scripting language JavaScript.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each process and/or block in the flowchart illustrations and/or block diagrams, and combinations of processes and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions executed by the processor of the computer or other programmable data processing device produce a use A device for realizing the functions specified in one process or multiple processes of the flowchart and/or one block or multiple blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory that causes a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction means, the instructions The device implements the functions specified in a process or processes of the flowchart and/or a block or blocks of the block diagram.

These computer program instructions may also be loaded onto a computer or other programmable data processing device, causing a series of operating steps to be performed on the computer or other programmable device to produce computer-implemented processing, thereby executing on the computer or other programmable device. Instructions provide steps for implementing the functions specified in a process or processes of a flowchart diagram and/or a block or blocks of a block diagram.

Although the preferred embodiments of the present application have been described, those skilled in the art will be able to make additional changes and modifications to these embodiments once the basic inventive concepts are apparent. Therefore, it is intended that the appended claims be construed to include the preferred embodiments and all changes and modifications that fall within the scope of this application.

Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. In this way, if these modifications and variations of the present application fall within the scope of the claims of the present application and equivalent technologies, the present application is also intended to include these modifications and variations.

Claims (10)

1. A traveling control hydraulic system for silage machines, which is characterized in that it includes a variable plunger pump (1), an oil charge pump (2), a right front accumulator (8.1), a left front accumulator (8.2), a left front one-way Valve (9.2), right front one-way valve (9.1), left front variable plunger motor (10), rear axle variable plunger motor (11), right front variable plunger motor (12), among which: The variable piston pump (1) and charge pump (2) are drivingly connected to the power output device. Port A of the variable piston pump (1) is connected to the left front variable piston motor (10) and the rear axle variable piston respectively. The A port of the motor (11) and the right front variable piston motor (12) are connected, and the B port of the variable piston pump (1) is connected to the left front variable piston motor (10) and the rear axle variable piston motor (11) respectively. ) and the B port of the right front variable piston motor (12) are connected; the output end of the charge pump (2) is connected to the A port of the left front variable piston motor (10) and the right front variable piston motor (10) through the left front one-way valve (9.2) respectively. The one-way valve (9.1) is connected to port A of the right front variable piston motor (12). The left front accumulator (8.2) is connected to the input end of the left front one-way valve (9.2) and next to the right front accumulator (8.1). Connect to the input end of the right front one-way valve (9.1). 2. The travel control hydraulic system for silage machines according to claim 1, characterized in that it also includes a second relief valve (4), two first relief valves (3), and two first relief valves. (3) After series connection, it is arranged in parallel between port A and port B of the variable displacement piston pump (1); the second relief valve (4) is connected to the output end of the oil charge pump (2). 3. The travel control hydraulic system for silage machines according to claim 1 or 2, characterized in that it also includes a one-way valve (7), the output end of the one-way valve (7) is connected to the oil supply pump (2) ), and the input end of the one-way valve (7) is connected to the right front accumulator (8.1) and the left front accumulator (8.2) respectively. 4. The travel control hydraulic system for silage machines according to claim 3, characterized in that it also includes a third relief valve (6), the third relief valve (6) is bypassed to the one-way valve. The input terminal of (7). 5. The traveling control hydraulic system for silage machines according to claim 3, characterized in that it also includes a first pressure sensor (5) and a second pressure sensor (13), and the first pressure sensor (5) and the The output end of the oil charge pump (2) is connected to detect the outlet pressure of the oil charge pump (2); the second pressure sensor (13) is bypassed to the one-way valve (7) and the right front accumulator. The pipeline between (8.1) and the left front accumulator (8.2) is used to detect the pressure in the right front accumulator (8.1) and the left front accumulator (8.2). 6. A control method for the traveling control hydraulic system of a silage machine according to any one of claims 1 to 5, characterized in that it includes the steps: Get the current pedal pedaling angle; According to the range of the actual pedaling angle, the variable piston pump (1), the left front variable piston motor (10), the rear axle variable piston motor (11), and the right front variable piston motor are controlled according to the corresponding displacement change slope. The displacement of (12) is to output a corresponding amount of hydrostatic braking force to achieve gradual deceleration of the vehicle; and only after the actual pedaling angle reaches the set threshold, while outputting a corresponding amount of hydrostatic braking force, the vehicle is also decelerated according to the The size of the actual pedaling angle drives the foot brake valve to output hydraulic pressure to the brake caliper to generate a corresponding friction braking force to achieve emergency braking of the vehicle, wherein the displacement change slope, the hydraulic pressure output by the footbrake valve and the actual pedaling The size of the angle is positively related. 7. The control method according to claim 6, characterized in that the variable piston pump (1) and the left front variable piston motor (1) are controlled according to the corresponding displacement change slope according to the interval where the actual pedaling angle is located. 10), the displacement of the rear axle variable piston motor (11) and the right front variable piston motor (12) is to output a corresponding amount of hydrostatic power to achieve gradual vehicle deceleration; and only when the actual pedaling angle reaches the setting After the threshold, while outputting a corresponding amount of hydrostatic braking force, the foot brake valve is also driven according to the actual pedaling angle to output hydraulic pressure to the brake caliper to generate a corresponding amount of friction braking force to achieve vehicle emergency braking, which specifically includes steps : If the current stepping angle of the pedal θ<θ ₀ , the vehicle is in a normal driving state by default. At this time, the vehicle's driving speed is controlled by the handle, and the control system close-loop controls the vehicle speed and the handle current value to match each other; If the current pedal angle θ ₀ ≤ θ ≤ θ ₁ , the control system overrides the handle control and controls the variable piston pump (1), left front variable piston motor (10), and rear axle with the first displacement change slope K _θX1 The displacements of the variable piston motor (11) and the right front variable piston motor (12) are used to output corresponding amounts of hydrostatic power to achieve gradual vehicle deceleration; If the current pedal angle θ ₁ <θ ≤ θ ₂ , the control system overrides the handle control and controls the variable piston pump (1), left front variable piston motor (10), and rear axle with the second displacement change slope K _θX2 The displacement of the variable piston motor (11) and the right front variable piston motor (12) is used to output a corresponding amount of hydrostatic force, where K _θX1 <K _θX2 ; at the same time, the foot brake valve is adjusted according to the actual pedaling angle. The output hydraulic pressure acts on the brake caliper to generate a corresponding friction braking force to implement emergency braking of the vehicle. The friction braking force is positively related to the actual pedaling angle. 8. The control method according to claim 7, wherein the first displacement change slope K _θX1 and the second displacement change slope K _θX2 are specifically: _{Among them : θ _} Slope; k ₀ and k ₁ are the displacement change slope of the pump and motor displacement that need to be controlled when decelerating when the pedal pedaling angle is θ ₀ and θ ₁ respectively; θ _X2 is the pedal pedaling angle at (θ ₁ , θ ₂ ] The real _- time feedback value within the _{interval , K} θ It is necessary to control the displacement change slope of pump and motor displacement changes. 9. The control method according to claim 7, characterized in that if the current pedal angle θ ₀ ≤ θ ≤ θ ₁ , the control system overrides the handle control and controls the variable with the first displacement change slope K _θX1 The displacements of the plunger pump (1), left front variable piston motor (10), rear axle variable piston motor (11), and right front variable piston motor (12) are designed to output corresponding amounts of hydrostatic force to achieve the gradual descent of the vehicle. speed, specifically including steps: If the motor current I _m =0, each motor is at the maximum displacement and the hydraulic system is in the pump speed regulation state. At this time, the variable plunger pump (1) is controlled to reduce the pump displacement with the first displacement change slope K _θX1 . Until the vehicle decelerates to 0; If the motor current I _m ≠ 0, the hydraulic system is in the state of maximum pump displacement and motor variable displacement speed regulation. At this time, the first displacement change slope K θX1 is used to control each motor to increase to the maximum displacement, and then the third displacement change slope K _θX1 is used to control each motor to increase to the maximum displacement. A displacement change slope K _θX1 controls the variable displacement piston pump (1) to reduce the pump displacement until the vehicle decelerates to 0. 10. The control method according to claim 7, characterized in that if the current pedal angle θ ₁ <θ ≤ θ ₂ , the control system overrides the handle control and controls the variable with the second displacement change slope K _θX2 The displacements of the plunger pump (1), left front variable piston motor (10), rear axle variable piston motor (11), and right front variable piston motor (12) are designed to output corresponding amounts of hydrostatic force to achieve the gradual descent of the vehicle. speed, specifically including steps: If the motor current I _m =0, each motor is at the maximum displacement and the hydraulic system is in the pump speed regulation state. At this time, the variable plunger pump (1) is controlled to reduce the pump displacement with the second displacement change slope K _θX2 . Until the vehicle decelerates to 0; If the motor current I _m ≠ 0, the hydraulic system is in a state of maximum pump displacement and motor variable displacement speed regulation. At this time, the second displacement change slope K _θX2 is used to simultaneously control each motor to increase displacement and the variable piston pump. (1) Reduce the pump displacement until the vehicle decelerates to 0; or, If the motor current I _m ≠ 0, the hydraulic system is in the state of maximum pump displacement and motor variable displacement speed regulation. At this time, the second displacement change slope K θX2 is first used to control each motor to increase to the maximum displacement, and then the second displacement change slope K _θX2 is used to control each motor to increase to the maximum displacement. The second displacement change slope K _θX2 controls the variable displacement piston pump (1) to reduce the pump displacement until the vehicle decelerates to 0.