Hydraulic control method and control system for self-correction of running deviation of excavator

Abstract

The application discloses a kind of excavator walking deviation self-correction hydraulic control method and control system thereof, which belongs to the technical field of engineering machinery.It solves the defects of walking deviation in the walking process of left and right walking motors of traditional excavator in the prior art.The main structure includes compensation system, control system, left pump, right pump, right walking valve, left walking valve, straight walking valve, left walking motor and right walking motor, the compensation system is connected with left walking motor and right walking motor respectively, the control system is connected with left walking motor and right walking motor respectively, the left pump is connected with left walking valve and straight walking valve respectively, the right pump is connected with right walking valve through straight walking valve, left walking valve is also connected with left walking motor, and right walking valve is also connected with right walking motor.The application is mainly used in excavators and other engineering machinery.

Description

Technical Field

[0001] This invention belongs to the field of engineering machinery technology, and more specifically, it relates to a hydraulic control method and control system for self-correcting the travel deviation of an excavator. Background Technology

[0002] Excavator travel deviation is a common problem, and there are several reasons for it. First, when two pumps supply oil to two travel motors respectively, differences in load, efficiency, pump displacement, and volumetric efficiency during travel will cause variations in the flow rate to the two motors, resulting in travel deviation. Second, when two pumps supply oil to two travel motors for combined travel actions, if main pump 1 supplies oil for combined actions, the load on the left travel motor supplied by main pump 1 is inconsistent with the load of other actions. More flow goes to the side with the smaller load, and the flow to the left travel motor is obviously inconsistent with the flow to the right travel motor supplied by main pump 2, also resulting in travel deviation. Third, when both travel motors are supplied oil by main pump 1, this avoids the difference in flow rate caused by different loads during combined actions. However, the load on the two travel motors will still be different during travel, leading to different flow rates and ultimately, travel deviation.

[0003] The problem of misalignment between the two travel motors ultimately stems from the different flow rates to them, resulting in different motor speeds. For misalignment caused by the second scenario, existing excavators often employ a linear travel valve design to avoid the impact of combined movements on travel. The existing technical solution is as follows: Existing excavators often use a linear travel valve design to ensure consistent rotational speeds of the two travel motors. The specific solution is as follows: Figure 5 As shown: During single-movement operation, the solenoid E of the linear travel valve is not energized, and the linear travel valve operates in the right position. When performing single-movement leftward movement, the solenoid A of the main valve leftward linkage is energized, and the main valve leftward linkage operates in the left position. The hydraulic oil from the main pump 1 enters the leftward motor through the main valve leftward linkage, achieving forward movement. Similarly, when solenoid B is energized, the leftward movement achieves backward movement. When the rightward motor operates alone, the main pump 2 supplies oil to the rightward motor through the main valve rightward linkage, and the working principle is the same as the single-movement principle of the leftward motor. For example... Figure 5As shown, when both left and right travel motors operate simultaneously, if there is no compound action, the solenoid E of the linear travel valve remains de-energized, and the two pumps supply oil to the two travel motors individually. When a compound action occurs, the solenoid E of the linear travel valve is energized, and the solenoid valve operates in the left position. Main pump 1 supplies oil to the left travel motor through channel 1 of the left travel linkage of the main valve, and simultaneously supplies oil to the right travel motor through channel 2 of the linear travel valve and channel 3 of the right travel linkage of the main valve. The flow from main pump 2 enters other working linkages of the main valve. This design ensures that the flow entering the travel motors is not affected by other actions. Even if main pump 1 simultaneously supplies oil to other working linkages, it can ensure that, ideally, the load on the two travel motors is approximately the same, thus ensuring an equal distribution of flow into the two travel motors, thereby ensuring that the two travel motors rotate at the same speed and achieve linear travel. Therefore, it can be seen that the core of the existing technology is that when both travel motors are working and there is a compound action, the oil supply to both travel motors is from the same oil source, eliminating the impact of the compound action on the flow into the two travel motors.

[0004] However, the drawbacks of the existing technology are as follows: In straight-line walking conditions, the left and right walking motors are supplied with oil by the main pump 1, that is, the same power source is used to ensure that the flow into the two walking motors is as consistent as possible. However, it only solves the problem of walking deviation when the two walking motors are under the same load. Due to the different road surfaces, the loads of the two walking motors will inevitably be different. Even with the same oil source, more flow will flow to the side with a smaller load, while the side with a larger load will receive less flow. The difference in flow between the two walking motors will cause walking deviation, and the existing technology cannot correct the walking motor that is deviating. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a self-correcting hydraulic control method and control system for excavator travel deviation. It can compensate for the flow of the travel motor with a small input flow, with good compensation effect and high accuracy, and solves the problem of travel deviation caused by inconsistent flow into the travel motor due to various factors.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] A hydraulic control method for self-correcting travel deviation in an excavator includes an operation method for the travel motor in forward mode, an operation method for self-correcting travel deviation in forward mode, an operation method for the travel motor in reverse mode, and an operation method for self-correcting travel deviation in reverse mode.

[0008] Preferably, the operating method of the walking motor in forward mode includes the following steps:

[0009] When the travel motor is moving in a straight line, the solenoid E of the linear travel valve is energized, and the linear travel valve operates in the left position. The solenoid A of the left travel valve is energized, and the left travel valve operates in the left position. The flow from the left pump passes through channel one of the left travel valve, and then through the hydraulic control check valve one to supply oil to port A1 of the left travel motor. At the same time, the flow passes through channel seven of the linear travel valve, channel three of the right travel valve, and then through the hydraulic control check valve three to supply oil to port A2 of the right travel motor. Shuttle valve one transmits the hydraulic signals from the two travel motors to the hydraulic control check valves two and four, causing the hydraulic control check valves two and four to open in opposite directions. The flow entering the left travel motor passes through port B1, the hydraulic control check valve two, and then through channel two of the left travel valve back to the oil tank. The flow entering the right travel motor passes through port B2, the hydraulic control check valve four, and then through channel four of the right travel valve back to the oil tank. This cycle drives the travel motor to move forward.

[0010] Preferably, the self-correction method for travel deviation during forward movement of the travel motor includes the following steps:

[0011] When external factors cause inconsistent flow rates to the two travel motors, such as increased load on the left travel motor due to uneven road surface, the flow rate to the left travel motor decreases, resulting in slower left travel and faster right travel. At this time, the speed signals of the left travel motor detected by speed sensor 1 and the right travel motor detected by speed sensor 2 are transmitted to the processor after passing through a digital-to-analog converter and a comparator. The processor energizes the solenoid F of the reversing valve according to the speed signals, and the reversing valve operates in the left position. At the same time, it energizes the solenoid H of the servo valve, and the servo valve operates in the right position. The flow rate of the auxiliary high-pressure pump enters the reversing valve through the servo valve's channel nine and then through the check valve five to supply oil to the oil port A1 of the left travel motor, compensating for the flow rate of the left travel motor and achieving precise consistency in the flow rates entering the left and right travel motors. Finally, it adjusts the speed of the left and right travel motors to be consistent.

[0012] When external factors cause the right travel motor to run too slowly, the processor energizes the solenoid F of the reversing valve, causing the reversing valve to operate in the left position. At the same time, it energizes the solenoid G of the servo valve, causing the servo valve to operate in the left position. The flow from the auxiliary high-pressure pump enters the reversing valve through channel eight of the servo valve, and then supplies oil to the oil port A2 of the right travel motor through check valve four. This compensates for the flow of the right travel motor, ensuring that the flow entering the left and right travel motors is precisely consistent. Throughout the process, the flow of the travel motor with a small input flow can be compensated, and the travel deviation can be automatically corrected. At the same time, the opening area of ​​the servo valve can be adjusted according to the speed difference to control the amount of compensation flow.

[0013] Preferably, the method for operating the walking motor in reverse includes the following steps:

[0014] When the travel motor is in linear reverse operation, the solenoid E of the linear travel valve is energized, and the linear travel valve operates in the left position. The solenoid B of the left travel valve is energized, and the left travel valve operates in the right position. The flow from the left pump passes through channel eleven of the left travel valve, then through hydraulic check valve two, and supplies oil to port B1 of the left travel motor. At the same time, it passes through channel seven of the linear travel valve, enters channel thirteen of the right travel valve, and then through hydraulic check valve four, supplying oil to port B2 of the right travel motor. Shuttle valve two transmits the hydraulic signals from the left and right travel motors to hydraulic check valves one and three. Hydraulic check valves one and three open in opposite directions. The flow entering the left travel motor passes through port A1, hydraulic check valve one, and then through channel ten of the left travel valve back to the oil tank. The flow entering the right travel motor passes through port A2, hydraulic check valve three, and then through channel twelve of the right travel valve back to the oil tank. This cycle drives the travel motor to perform the reverse movement.

[0015] Preferably, the self-correction method for travel deviation during reverse operation of the travel motor includes the following steps:

[0016] When external factors cause inconsistent flow rates to the two travel motors, such as increased load on the left travel motor due to uneven road surface, the flow rate into the left travel motor decreases, resulting in slower left travel and faster right travel. At this time, the speed signals of the left travel motor detected by speed sensor 1 and the right travel motor detected by speed sensor 2 are transmitted to the processor after passing through a digital-to-analog converter and a comparator. Based on the speed signals, the processor de-energizes the solenoid F of the reversing valve, and the reversing valve operates in the right position. At the same time, it energizes the solenoid G of the servo valve, and the servo valve operates in the left position. The flow rate of the auxiliary high-pressure pump enters the reversing valve channel 15 through the servo valve channel 8, and then supplies oil to the oil port B1 of the left travel motor through the check valve 2 to compensate for the flow rate of the left travel motor, so as to maintain precise consistency of the flow rate entering the left and right travel motors, and finally adjust the speed of the left and right travel motors to be consistent.

[0017] When external factors cause the right travel motor to run too slowly, the processor de-energizes the solenoid F of the reversing valve, causing the reversing valve to operate in the right position. Simultaneously, it energizes the solenoid H of the servo valve, causing the servo valve to operate in the right position. The flow from the auxiliary high-pressure pump enters the reversing valve's channel fourteen through the servo valve's channel nine, and then supplies oil to the right travel motor's oil port B2 through the check valve three. This compensates for the flow to the right travel motor, ensuring precise consistency between the flow entering the left and right travel motors. Throughout this process, flow compensation can be performed on travel motors with low input flow, and travel deviation can be automatically corrected. At the same time, the opening area of ​​the servo valve can be adjusted according to the speed difference to control the magnitude of the compensation flow.

[0018] An excavator travel deviation self-correcting hydraulic control system according to any one of the above-mentioned excavator travel deviation self-correcting hydraulic control methods includes a compensation system, a control system, a left pump, a right pump, a right travel valve, a left travel valve, a linear travel valve, a left travel motor, and a right travel motor. The compensation system is connected to the left travel motor and the right travel motor respectively. The control system is connected to the left travel motor and the right travel motor respectively. The left pump is connected to the left travel valve and the linear travel valve respectively. The right pump is connected to the right travel valve through the linear travel valve. The left travel valve is also connected to the left travel motor, and the right travel valve is also connected to the right travel motor.

[0019] Preferably, the compensation system includes an auxiliary high-pressure pump, a servo valve, a directional valve, a hydraulically controlled check valve one, a hydraulically controlled check valve two, a shuttle valve one, a shuttle valve two, a hydraulically controlled check valve three, and a hydraulically controlled check valve four. The auxiliary high-pressure pump is connected to the directional valve via the servo valve. The directional valve is also connected to the left travel motor and the right travel motor respectively. Shuttle valve one is connected to the left travel valve, the right travel valve, hydraulically controlled check valve two, and hydraulically controlled check valve four respectively. Hydraulically controlled check valve two is also connected to port B1 of the left travel motor, and hydraulically controlled check valve four is also connected to port B2 of the right travel motor. Shuttle valve two is connected to the left travel valve, the right travel valve, hydraulically controlled check valve one, and hydraulically controlled check valve three respectively. Hydraulically controlled check valve one is also connected to port A1 of the left travel motor, and hydraulically controlled check valve three is also connected to port A2 of the right travel motor.

[0020] Preferably, a check valve five is provided between channel five on the reversing valve and oil port A1 of the left travel motor, a check valve four is provided between channel six on the reversing valve and oil port A2 of the right travel motor, a check valve three is provided between channel fourteen on the reversing valve and oil port B2 of the right travel motor, and a check valve two is provided between channel fifteen on the reversing valve and oil port B1 of the left travel motor.

[0021] Preferably, the control system includes a processor, a digital-to-analog converter, a speed sensor 1 mounted on the left travel motor for detecting the speed signal of the left travel motor, and a speed sensor 2 mounted on the right travel motor for detecting the speed signal of the right travel motor. The digital-to-analog converter is connected to the speed sensor 1 and the speed sensor 2 respectively, and the digital-to-analog converter is also connected to the processor through a comparator.

[0022] Preferably, the oil outlets of both the left and right pumps are connected back to the oil tank via a one-way valve and a safety valve, and a safety valve is provided at the oil outlet of the auxiliary high-pressure pump.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] 1. The auxiliary high-pressure pump is the power source for flow compensation. It provides flow compensation for the traveling motor with a smaller input flow and slower speed, so that the two traveling motors maintain the same input flow and thus ensure that the two traveling motors have the same speed.

[0025] 2. The energizing and de-energizing signals of the servo valve solenoids G and H come from the processor and are related to the speed difference of the travel motor. When the speed difference is large, the current of the servo valve solenoids is larger, the valve core opening is larger, and the flow rate entering the compensated travel motor is larger.

[0026] 3. The function of the reversing valve is to determine the working position of the valve core according to the forward and reverse rotation of the travel motor. When the travel motor moves forward, the solenoid F of the reversing valve is energized and the reversing valve works in the left position. When the travel motor moves backward, the solenoid F of the reversing valve is de-energized and the reversing valve works in the right position. When moving forward, the auxiliary high-pressure pump provides flow to the oil port A1 of the left travel motor or the oil port A2 of the right travel motor according to the signal from the controller, that is, the speed signal of the travel motor. When moving backward, the auxiliary high-pressure pump provides flow to the oil port B1 of the left travel motor or the oil port B2 of the right travel motor.

[0027] 4. The functions of check valves 2, 3, 4 and 5 are to prevent the high-pressure oil from the left pump from flowing back into the compensation system oil circuit when traveling in a straight line.

[0028] 5. The function of check valve one is to prevent the pressure of the left pump and the right pump from affecting each other. Safety valve one is an overflow valve to prevent the pressure of the hydraulic system from being too high and to protect the system. Safety valve two is installed at the oil outlet of the auxiliary high pressure pump. Safety valve two provides protection for the system and prevents the hydraulic pipeline from being damaged by excessive pressure.

[0029] 6. When the travel motor moves forward, shuttle valve one selects the pressure of the left and right travel motors and transmits it to hydraulic control check valve two and control check valve four, so that the return oil circuits of the left and right travel motors can be opened normally; when the travel motor moves backward, shuttle valve two selects the pressure of the left and right travel motors and transmits it to hydraulic control check valve one and control check valve three, so that the return oil circuits of the left and right travel motors can be opened normally; the use of hydraulic control check valves can ensure that the flow compensated to the left travel motor will not leak to the right travel motor through the left and right travel valves, ensuring that the compensation flow of the auxiliary high pressure pump can smoothly reach the compensated hydraulic motor;

[0030] 7. Speed ​​sensor 1 and speed sensor 2 are responsible for detecting the rotational speed of the two travel motors. The analog-to-digital converter is responsible for converting the detected analog speed signal into a digital signal. The comparator is responsible for comparing the rotational speed signals of the two travel motors and transmitting the signal to the whole machine processor. The processor controls the energization of the electromagnets of the reversing valve and servo valve according to the rotational speed and direction signals of the travel motors. Finally, the flow of the auxiliary high-pressure pump is distributed to the travel motor with a smaller input flow and slower speed. Flow compensation is performed on the slower-speed travel motor to ensure the straightness of left and right movement.

[0031] In summary, this invention can compensate for the flow rate of travel motors with low input flow rate, with good compensation effect and high accuracy. It solves the problem of travel deviation caused by inconsistent flow rates into the travel motor due to various factors, such as different volumetric efficiencies of the two travel motors or different loads on the travel motors due to uneven road surfaces. When the input flow rates of the left and right travel motors are inconsistent, this invention has an automatic adjustment and correction function. When the travel motors deviate from their normal direction, the system can automatically adjust according to the rotational speed of the two travel motors to ensure that the flow rates entering the two travel motors are consistent, enabling the excavator to maintain straight-line travel under various working conditions. Attached Figure Description

[0032] Figure 1 This is a system schematic diagram of the present invention;

[0033] Figure 2 This is a schematic diagram of the system principle when the walking motor moves in a straight line in this invention;

[0034] Figure 3 This is a schematic diagram of the system principle when the walking motor moves backward in a straight line in this invention;

[0035] Figure 4 This is a block diagram illustrating the principle of the walking motor moving forward and backward in a straight line in this invention;

[0036] Figure 5 This is a simplified diagram of the system principle of existing technology.

[0037] In the diagram: 1. Left pump; 2. Right pump; 3. Auxiliary high-pressure pump; 4. Check valve one; 5. Safety valve one; 6. Safety valve two; 7. Servo valve; 8. Directional valve; 9. Right travel valve; 10. Check valve two; 11. Check valve three; 12. Right travel motor; 13. Check valve four; 14. Check valve five; 15. Processor; 16. Digital-to-analog converter; 17. Comparator; 18. Left travel motor; 19. Hydraulic check valve one; 20. Hydraulic check valve two; 21. Shuttle valve one; 22. Shuttle valve two; 23. Left travel valve; 24. Linear travel valve; 25. Engine; 26. Speed ​​sensor one; 27. Speed ​​sensor two; 28. Hydraulic check valve three; 29. ​​Hydraulic check valve four. Detailed Implementation

[0038] The present invention will be further described below with reference to specific embodiments and accompanying drawings.

[0039] Example 1:

[0040] like Figure 1As shown, a hydraulic control method for self-correcting travel deviation of an excavator includes an operation method for the travel motor in forward mode, an operation method for self-correcting travel deviation in the travel motor in forward mode, an operation method for the travel motor in reverse mode, and an operation method for self-correcting travel deviation in the travel motor in reverse mode.

[0041] The operating method for the forward movement of the walking motor includes the following steps:

[0042] like Figure 2 As shown, when the travel motor is moving in a straight line, the electromagnet E of the linear travel valve 24 is energized, and the linear travel valve 24 operates in the left position. The electromagnet A of the left travel valve 23 is energized, and the left travel valve 23 operates in the left position. The flow of the left pump 1 passes through channel one of the left travel valve 23, and then through the hydraulic control check valve 19 to supply oil to port A1 of the left travel motor 18. At the same time, the flow passes through channel seven of the linear travel valve 24, channel three of the right travel valve 9, and then through the hydraulic control check valve 28 to supply oil to port A2 of the right travel motor 12. Shuttle valve 21 transmits the hydraulic signals of the two travel motors to hydraulic control check valves 20 and 29, causing them to open in opposite directions. The flow into the left travel motor 18 passes through port B1, hydraulic control check valve 20, and then through channel 2 of the left travel valve 23 back to the oil tank. The flow into the right travel motor 12 passes through port B2, hydraulic control check valve 29, and then through channel 4 of the right travel valve 9 back to the oil tank. This cycle drives the travel motors to move forward.

[0043] The self-correction method for travel motor deviation during forward operation includes the following steps:

[0044] like Figure 4 As shown, when external factors cause the flow rates entering the two travel motors to be inconsistent, such as an increased load on the left travel motor due to uneven road surface, the flow rate into the left travel motor 18 decreases, resulting in slower left travel and faster right travel. At this time, the speed signals of the left travel motor 18 detected by speed sensor 1 26 and the right travel motor 12 detected by speed sensor 27 are transmitted to the processor 15 after passing through the digital-to-analog converter 16 and comparator 17. The processor 15 energizes the electromagnet F of the reversing valve 8 according to the speed signals, and the reversing valve 8 operates in the left position. At the same time, it energizes the electromagnet H of the servo valve 7, and the servo valve 7 operates in the right position. The flow rate of the auxiliary high-pressure pump 3 enters the reversing valve 8 through the channel 9 of the servo valve 7 and then supplies oil to the oil port A1 of the left travel motor 18 through the check valve 5 14 to compensate for the flow rate of the left travel motor 18, so as to maintain a precise consistency in the flow rate entering the left travel motor 18 and the right travel motor 12, and finally adjust the rotation speed of the left travel motor 18 and the right travel motor 12 to be consistent.

[0045] When external factors cause the right travel motor 12 to run too slowly, the processor 15 energizes the solenoid F of the reversing valve 8, causing the reversing valve 8 to operate in the left position. At the same time, it energizes the solenoid G of the servo valve 7, causing the servo valve 7 to operate in the left position. The flow of the auxiliary high-pressure pump 3 enters the reversing valve 8 through the channel 8 of the servo valve 7, and then supplies oil to the oil port A2 of the right travel motor 12 through the check valve 13. This compensates for the flow of the right travel motor 12, ensuring that the flow into the left travel motor 18 and the right travel motor 12 remains precisely consistent. Throughout the process, the flow of the travel motor with a small input flow can be compensated, and the travel deviation can be automatically corrected. At the same time, the opening area of ​​the servo valve 7 can be adjusted according to the speed difference to control the amount of compensation flow.

[0046] The operation method for the walking motor in reverse mode includes the following steps:

[0047] like Figure 3 As shown, when the travel motor is in linear reverse operation, the solenoid E of the linear travel valve 24 is energized, and the linear travel valve 24 operates in the left position. The solenoid B of the left travel valve 23 is energized, and the left travel valve 23 operates in the right position. The flow of the left pump 1 passes through channel eleven of the left travel valve 23, then through the hydraulic control check valve 20, and supplies oil to port B1 of the left travel motor 18. At the same time, it passes through channel seven of the linear travel valve 24, enters channel thirteen of the right travel valve 9, and then through the hydraulic control check valve 29 to supply oil to port B2 of the right travel motor 12. Shuttle valve 2... 22 transmits the hydraulic signals of the left travel motor 18 and the right travel motor 12 to the hydraulic control check valve 19 and the hydraulic control check valve 28. The hydraulic control check valve 19 and the hydraulic control check valve 28 open in opposite directions. The flow entering the left travel motor 18 passes through oil port A1, hydraulic control check valve 19, and then through the channel 10 of the left travel valve 23 back to the oil tank. The flow entering the right travel motor 12 passes through oil port A2, hydraulic control check valve 28, and then through the channel 12 of the right travel valve 9 back to the oil tank. This cycle drives the travel motor to perform the backward movement.

[0048] The self-correction method for travel motor deviation during reverse operation includes the following steps:

[0049] For example Figure 4As shown, when external factors cause the flow rates entering the two travel motors to be inconsistent, such as an increased load on the left travel motor due to uneven road surface, the flow rate into the left travel motor 18 decreases, resulting in slower left travel and faster right travel. At this time, the speed signals of the left travel motor 18 detected by speed sensor 1 26 and the right travel motor 12 detected by speed sensor 27 are transmitted to the processor 15 after passing through the digital-to-analog converter 16 and comparator 17. The processor 15 de-energizes the electromagnet F of the reversing valve 8 according to the speed signals, and the reversing valve 8 operates in the right position. At the same time, the electromagnet G of the servo valve 7 is energized, and the servo valve 7 operates in the left position. The flow rate of the auxiliary high-pressure pump 3 enters the reversing valve 8 through the channel 8 of the servo valve 7 and then supplies oil to the oil port B1 of the left travel motor 18 through the check valve 2 10 to compensate for the flow rate of the left travel motor 18, so as to maintain a precise consistency in the flow rate entering the left travel motor 18 and the right travel motor 12, and finally adjust the rotation speed of the left travel motor 18 and the right travel motor 12 to be consistent.

[0050] When external factors cause the right travel motor 12 to run too slowly, the processor 15 de-energizes the solenoid F of the reversing valve 8, causing the reversing valve 8 to operate in the right position. At the same time, the solenoid H of the servo valve 7 is energized, causing the servo valve 7 to operate in the right position. The flow of the auxiliary high-pressure pump 3 enters the reversing valve 8 through the channel nine of the servo valve 7, and then supplies oil to the oil port B2 of the right travel motor 12 through the check valve three 11. This compensates for the flow of the right travel motor 12, ensuring that the flow into the left travel motor 18 and the right travel motor 12 remains precisely consistent. Throughout the process, the flow of the travel motor with a small input flow can be compensated, and the travel deviation can be automatically corrected. At the same time, the opening area of ​​the servo valve 7 can be adjusted according to the speed difference to control the amount of compensation flow.

[0051] Example 2:

[0052] An excavator travel deviation self-correcting hydraulic control system according to the excavator travel deviation self-correcting hydraulic control method of Embodiment 1 includes a compensation system, a control system, a left pump 1, a right pump 2, a right travel valve 9, a left travel valve 23, a linear travel valve 24, a left travel motor 18, and a right travel motor 12. The compensation system is connected to the left travel motor 18 and the right travel motor 12 respectively. The control system is connected to the left travel motor 18 and the right travel motor 12 respectively. The left pump 1 is connected to the left travel valve 23 and the linear travel valve 24 respectively. The right pump 2 is connected to the right travel valve 9 through the linear travel valve 24. The left travel valve 23 is also connected to the left travel motor 18, and the right travel valve 9 is also connected to the right travel motor 12.

[0053] For example Figure 3As shown, the solenoid E of the linear travel valve 24 is energized only when linear travel is required. When the linear travel valve 24 is in the left position, the engine 25 rotates, driving the left pump 1 to provide the main power source for the two travel motors, providing the main flow to the left travel motor 18 and the right travel motor 12. The flow from the right pump 2 enters other working links of the main valve and no longer provides flow to the travel motors. The left travel valve 23 and the right travel valve 9 are both three-position six-way solenoid directional valves. By energizing or de-energizing the solenoids at both ends of the solenoid valve, the flow configuration of the travel motor is realized, controlling the direction and magnitude of oil inlet and outlet of the travel motor, and further determining the rotation direction of the travel motor, that is, the travel direction of the excavator.

[0054] The compensation system includes an auxiliary high-pressure pump 3, a servo valve 7, a reversing valve 8, a hydraulically controlled check valve 19, a hydraulically controlled check valve 20, a shuttle valve 11, a shuttle valve 22, a hydraulically controlled check valve 3 28, and a hydraulically controlled check valve 4 29. The auxiliary high-pressure pump 3 is connected to the reversing valve 8 via the servo valve 7. The reversing valve 8 is also connected to the left travel motor 18 and the right travel motor 12, respectively. The shuttle valve 11 is connected to the left travel valve 23, the right travel valve 9, the hydraulically controlled check valve 20, and the hydraulically controlled check valve 4 29, respectively. One-way valve 4 29 is connected, hydraulic one-way valve 2 20 is also connected to port B1 of the left travel motor 18, and hydraulic one-way valve 4 29 is also connected to port B2 of the right travel motor 12; shuttle valve 2 22 is connected to left travel valve 23, right travel valve 9, hydraulic one-way valve 19 and hydraulic one-way valve 3 28 respectively, hydraulic one-way valve 19 is also connected to port A1 of the left travel motor 18, and hydraulic one-way valve 3 28 is also connected to port A2 of the right travel motor 12.

[0055] In this embodiment, the auxiliary high-pressure pump 3 in the compensation system becomes the power source for flow compensation, providing flow compensation for the travel motor with a smaller input flow and slower speed, so that the two travel motors maintain the same input flow, thereby ensuring that the two travel motors have the same speed. The energizing and de-energizing signals of the electromagnets G and H of the servo valve 7 come from the processor 15 and are related to the speed difference of the travel motors. When the speed difference is large, the current of the electromagnet of the servo valve 7 is larger, the opening of the valve core is larger, and the flow entering the compensated travel motor is larger. The function of the reversing valve 8 is to determine the working position of the valve core according to the forward and reverse rotation of the travel motor. Figure 2When the travel motor moves forward, the solenoid F of the reversing valve 8 is energized and operates in the left position. The auxiliary high-pressure pump 3, based on the signal from the controller 15 (i.e., the travel motor's speed signal), supplies flow to port A1 of the left travel motor 18 or port A2 of the right travel motor 12. When the travel motor moves backward, the solenoid F of the reversing valve 8 is de-energized and operates in the right position. The auxiliary high-pressure pump 3 supplies flow to port B1 of the left travel motor 18 or port B2 of the right travel motor 12. When the travel motor moves forward, shuttle valve 1 21 selects the pressure of the left travel motor 18 and the right travel motor 12 and transmits it to hydraulic check valve 2 20 and hydraulic check valve 4 29, allowing the return oil circuits of the left and right travel motors to open normally. When the travel motor moves backward, shuttle valve 2 22 selects the pressure of the left travel motor 18 and the right travel motor 12 and transmits it to hydraulic check valve 1 19 and hydraulic check valve 3 28, allowing the return oil circuits of the left and right travel motors to open normally. The use of a hydraulic check valve ensures that the flow compensated to the left travel motor 18 will not leak into the right travel motor 12 through the right travel valve 9 and the left travel valve 23, thus ensuring that the compensated flow from the auxiliary high-pressure pump 3 can smoothly reach the compensated hydraulic motor.

[0056] A check valve 5 14 is installed between channel 5 of the reversing valve 8 and port A1 of the left travel motor 18; a check valve 4 13 is installed between channel 6 of the reversing valve 8 and port A2 of the right travel motor 12; a check valve 3 11 is installed between channel 14 of the reversing valve 8 and port B2 of the right travel motor 12; and a check valve 2 10 is installed between channel 15 of the reversing valve 8 and port B1 of the left travel motor 18. The function of check valves 2 10, 3 11, 4 13, and 5 14 is to prevent the high-pressure oil from the left pump 1 from flowing back into the compensation system oil circuit during straight-line travel.

[0057] The control system includes a processor 15, a digital-to-analog converter 16, a speed sensor 26 mounted on the left travel motor 18 for detecting the speed signal of the left travel motor 18, and a speed sensor 27 mounted on the right travel motor 12 for detecting the speed signal of the right travel motor 12. The digital-to-analog converter 16 is connected to the speed sensor 26 and the speed sensor 27 respectively. The digital-to-analog converter 16 is also connected to the processor 15 through a comparator 17.

[0058] Speed ​​sensor 26 and speed sensor 27 are responsible for detecting the rotational speed of the two walking motors. The digital-to-analog converter 16 is responsible for converting the detected analog speed signal into a digital signal. The comparator 17 is responsible for comparing the rotational speed signals of the two walking motors and transmitting the signal to the whole machine processor 15. The processor 15 controls the energization of the electromagnets of the reversing valve 8 and the servo valve 7 according to the rotational speed and direction signals of the walking motors. Finally, it realizes flow compensation for the walking motor with smaller input flow and slower speed, ensuring the straightness of left and right walking.

[0059] The oil outlets of both the left pump 1 and the right pump 2 are connected back to the oil tank through one-way valve 4 and safety valve 5. The function of one-way valve 4 is to prevent the pressure of the left pump 1 and the right pump 2 from affecting each other. Safety valve 5 is a relief valve to prevent the hydraulic system pressure from being too high and to protect the system. A safety valve 6 is installed at the oil outlet of the auxiliary high-pressure pump 3. Safety valve 6 provides protection for the system and prevents the hydraulic pipeline from being damaged by excessive pressure.

Claims

1. A hydraulic control method for self-correcting the running deviation of an excavator, characterized by: This includes the operation methods for the forward travel motor, the operation methods for self-correction of travel deviation in the forward travel motor, the operation methods for the backward travel motor, and the operation methods for self-correction of travel deviation in the backward travel motor. The self-correction method for travel motor deviation during forward operation includes the following steps: When external factors cause inconsistent flow rates to the two travel motors, such as increased load on the left travel motor due to uneven road surface, the flow rate into the left travel motor (18) decreases, resulting in slower left travel and faster right travel. At this time, the speed signals of the left travel motor (18) detected by speed sensor one (26) and the right travel motor (12) detected by speed sensor two (27) are transmitted to the processor (15) after passing through the digital-to-analog converter (16) and comparator (17). The processor (15) energizes the electromagnet F of the reversing valve (8) according to the speed signal. (8) When the left position is working, the electromagnet H of the servo valve (7) is energized, the servo valve (7) is working in the right position, the flow of the auxiliary high pressure pump (3) enters the channel five of the reversing valve (8) through the channel nine of the servo valve (7), and then supplies oil to the oil port A1 of the left travel motor (18) through the check valve five (14) to compensate for the flow of the left travel motor (18), so as to achieve precise consistency of the flow entering the left travel motor (18) and the right travel motor (12), and finally adjust the speed of the left travel motor (18) and the right travel motor (12) to be consistent. The self-correction method for travel motor deviation during reverse operation includes the following steps: When external factors cause inconsistent flow rates to the two travel motors, such as increased load on the left travel motor due to uneven road surface, the flow rate into the left travel motor (18) decreases, resulting in slower left travel and faster right travel. At this time, the speed signals of the left travel motor (18) detected by speed sensor one (26) and the right travel motor (12) detected by speed sensor two (27) are transmitted to the processor (15) after passing through the digital-to-analog converter (16) and comparator (17). The processor (15) de-energizes the electromagnet F of the reversing valve (8) according to the speed signal. 8) When the right position is working, the electromagnet G of the servo valve (7) is energized, the servo valve (7) is working in the left position, and the flow of the auxiliary high pressure pump (3) enters the channel 15 of the reversing valve (8) through the channel 8 of the servo valve (7), and then supplies oil to the oil port B1 of the left travel motor (18) through the check valve 2 (10) to compensate for the flow of the left travel motor (18), so as to achieve precise consistency of the flow entering the left travel motor (18) and the right travel motor (12), and finally adjust the speed of the left travel motor (18) and the right travel motor (12) to be consistent.

2. The excavator travel run-off self-correcting hydraulic control method of claim 1, wherein: The operating method for the forward movement of the walking motor includes the following steps: When the travel motor is in forward operation, the electromagnet E of the linear travel valve (24) is energized, and the linear travel valve (24) operates in the left position. The electromagnet A of the left travel valve (23) is energized, and the left travel valve (23) operates in the left position. The flow of the left pump (1) passes through channel one of the left travel valve (23), and then through the hydraulic control check valve one (19) to supply oil to port A1 of the left travel motor (18). At the same time, the flow passes through channel seven of the linear travel valve (24), channel three of the right travel valve (9), and then through the hydraulic control check valve three (28) to supply oil to port A2 of the right travel motor (12). Valve 1 (21) transmits the hydraulic signals of the two travel motors to hydraulic control check valve 2 (20) and hydraulic control check valve 4 (29), causing hydraulic control check valve 2 (20) and hydraulic control check valve 4 (29) to open in opposite directions. The flow entering the left travel motor (18) passes through oil port B1, hydraulic control check valve 2 (20), and then through channel 2 of the left travel valve (23) back to the oil tank. The flow entering the right travel motor (12) passes through oil port B2, hydraulic control check valve 4 (29), and then through channel 4 of the right travel valve (9) back to the oil tank. This cycle drives the travel motor to perform forward movement.

3. The excavator travel run-off self-correcting hydraulic control method of claim 1, wherein: The self-correction method for travel motor deviation during forward operation also includes the following steps: When external factors cause the right travel motor (12) to run too slowly, the processor (15) energizes the electromagnet F of the reversing valve (8), and the reversing valve (8) operates in the left position. At the same time, the electromagnet G of the servo valve (7) is energized, and the servo valve (7) operates in the left position. The flow of the auxiliary high-pressure pump (3) enters the reversing valve (8) through the channel 8 of the servo valve (7), and then supplies oil to the oil port A2 of the right travel motor (12) through the check valve 4 (13) to compensate for the flow of the right travel motor (12) and achieve precise consistency between the flow entering the left travel motor (18) and the right travel motor (12).

4. The excavator travel run-off self-correcting hydraulic control method of claim 1, wherein: The operation method for the walking motor in reverse mode includes the following steps: When the travel motor is in reverse operation, the electromagnet E of the linear travel valve (24) is energized, and the linear travel valve (24) operates in the left position. The electromagnet B of the left travel valve (23) is energized, and the left travel valve (23) operates in the right position. The flow of the left pump (1) passes through channel eleven of the left travel valve (23), then through the hydraulic control check valve two (20), and supplies oil to the oil port B1 of the left travel motor (18). At the same time, it passes through channel seven of the linear travel valve (24), enters channel thirteen of the right travel valve (9), and then through the hydraulic control check valve four (29) to supply oil to the oil port B2 of the right travel motor (12). The shuttle valve two (22) The hydraulic signals of the left travel motor (18) and the right travel motor (12) are transmitted to the hydraulic control check valve 1 (19) and the hydraulic control check valve 3 (28). The hydraulic control check valve 1 (19) and the hydraulic control check valve 3 (28) open in opposite directions. The flow into the left travel motor (18) passes through oil port A1, hydraulic control check valve 1 (19), and then through the channel 10 of the left travel valve (23) back to the oil tank. The flow into the right travel motor (12) passes through oil port A2, hydraulic control check valve 3 (28), and then through the channel 12 of the right travel valve (9) back to the oil tank. This cycle drives the travel motor to perform the backward movement.

5. The excavator walk-off self-correcting hydraulic control method of claim 1, wherein: The self-correction method for travel motor deviation during reverse operation also includes the following steps: When external factors cause the right travel motor (12) to run too slowly, the processor (15) de-energizes the electromagnet F of the reversing valve (8), and the reversing valve (8) operates in the right position. At the same time, the electromagnet H of the servo valve (7) is energized, and the servo valve (7) operates in the right position. The flow of the auxiliary high-pressure pump (3) enters the reversing valve (8) through the nineth channel of the servo valve (7), and then supplies oil to the oil port B2 of the right travel motor (12) through the three-way valve (11) to compensate for the flow of the right travel motor (12) and achieve precise consistency between the flow entering the left travel motor (18) and the right travel motor (12).

6. A hydraulic control system for self-correcting the travel deviation of a shovel provided with a hydraulic control method for self-correcting the travel deviation of a shovel according to any one of claims 2 to 5, characterized by: It includes a compensation system, a control system, a left pump (1), a right pump (2), a right travel valve (9), a left travel valve (23), a linear travel valve (24), a left travel motor (18), and a right travel motor (12). The compensation system is connected to the left travel motor (18) and the right travel motor (12) respectively. The control system is connected to the left travel motor (18) and the right travel motor (12) respectively. The left pump (1) is connected to the left travel valve (23) and the linear travel valve (24) respectively. The right pump (2) is connected to the right travel valve (9) through the linear travel valve (24). The left travel valve (23) is also connected to the left travel motor (18). The right travel valve (9) is also connected to the right travel motor (12).

7. The excavator travel run-off correction hydraulic control system of claim 6, wherein: The compensation system includes an auxiliary high-pressure pump (3), a servo valve (7), a reversing valve (8), a hydraulic check valve one (19), a hydraulic check valve two (20), a shuttle valve one (21), a shuttle valve two (22), a hydraulic check valve three (28), and a hydraulic check valve four (29). The auxiliary high-pressure pump (3) is connected to the reversing valve (8) through the servo valve (7). The reversing valve (8) is also connected to the left travel motor (18) and the right travel motor (12) respectively. The shuttle valve one (21) is connected to the left travel valve (23), the right travel valve (9), and the hydraulic check valve two (20). 20) is connected to hydraulic control check valve four (29), hydraulic control check valve two (20) is also connected to port B1 of the left travel motor (18), hydraulic control check valve four (29) is also connected to port B2 of the right travel motor (12); shuttle valve two (22) is connected to the left travel valve (23), right travel valve (9), hydraulic control check valve one (19) and hydraulic control check valve three (28) respectively, hydraulic control check valve one (19) is also connected to port A1 of the left travel motor (18), hydraulic control check valve three (28) is also connected to port A2 of the right travel motor (12).

8. The excavator travel run-off correction hydraulic control system of claim 7, wherein: A check valve five (14) is provided between channel five on the reversing valve (8) and oil port A1 of the left travel motor (18), a check valve four (13) is provided between channel six on the reversing valve (8) and oil port A2 of the right travel motor (12), a check valve three (11) is provided between channel fourteen on the reversing valve (8) and oil port B2 of the right travel motor (12), and a check valve two (10) is provided between channel fifteen on the reversing valve (8) and oil port B1 of the left travel motor (18).

9. The excavator travel run-off correction hydraulic control system of claim 8, wherein: The control system includes a processor (15), a digital-to-analog converter (16), a speed sensor 1 (26) installed on the left walking motor (18) for detecting the speed signal of the left walking motor (18), and a speed sensor 2 (27) installed on the right walking motor (12) for detecting the speed signal of the right walking motor (12). The digital-to-analog converter (16) is connected to the speed sensor 1 (26) and the speed sensor 2 (27) respectively. The digital-to-analog converter (16) is also connected to the processor (15) through a comparator (17).

10. The excavator walk-off self-correcting hydraulic control system of claim 9, wherein: The oil outlets of the left pump (1) and the right pump (2) are connected back to the oil tank through one-way valve (4) and safety valve (5), and a safety valve (6) is provided at the oil outlet of the auxiliary high pressure pump (3).

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