Self-walking type heavy load platform leveling hydraulic system and self-walking type heavy load platform

Abstract

The invention discloses a self-walking type heavy load platform leveling hydraulic system and a self-walking type heavy load platform. The system comprises a hydraulic pump, a multi-way valve and a plurality of leveling units used for leveling upper structural parts of the self-walking type heavy load platform. Each leveling unit comprises a leveling oil cylinder control valve group, a leveling oil cylinder and a leveling oil cylinder displacement sensor; the hydraulic pump is connected with the leveling oil cylinder control valve group through the multi-way valve, and the leveling oil cylinder control valve group is connected with the leveling oil cylinder; and the controller obtains the current state of each leveling oil cylinder and controls the piston rod of each leveling oil cylinder to extend or retract according to a set control logic, so as to level the upper structural member of the self-walking heavy-load platform. Synchronous heavy-load lifting of the multiple leveling units is achieved, closed-loop control is achieved in the leveling process, the adjusting precision is improved, meanwhile, stepless adjustment of a heavy-load platform is achieved, pressure fluctuation is reduced, the stability of hydraulic damping is improved, and vibration impact on chassis structural parts is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of heavy-load platform leveling, and in particular relates to a self-propelled heavy-load platform leveling hydraulic system and a self-propelled heavy-load platform. Background Art

[0002] At present, self-propelled large-scale engineering equipment mainly adopts oil-gas suspension hydraulic system to level and damp the chassis frame. However, this type of system mainly adopts electromagnetic reversing valve or electromagnetic ball valve to control the oil inlet and return of the suspension cylinder, and maintains the pressure through accumulator. The main problems are as follows: First, when the height of the upper structure of the chassis or frame of self-propelled large-scale engineering equipment is very high (for example, 80-100M high), only adjusting the horizontality of the chassis or frame cannot ensure that the upper structure of the whole machine is vertical under the condition of walking on a slope road (because of the deflection of the upper structure itself); Second, the electromagnetic reversing valve or electromagnetic ball valve is used to control the extension and retraction of the suspension cylinder. In addition, the suspension cylinder has no displacement sensor, and cannot realize closed-loop position control, high-precision adjustment or leveling control, and the adjustment effect is not good; Third, due to the physical characteristics of the accumulator itself, the pressure maintenance effect is general and the pressure fluctuation is large. For large-scale engineering equipment with heavy weight (for example, upper weight of 3000-5000 tons), if it is traveling on uneven roads, the pressure fluctuation of the rodless chamber of the suspension cylinder will cause the hydraulic support force to be unstable, which will lead to unstable hydraulic shock absorption effect and vibration impact on the chassis structure, reducing the service life; Fourth, after the accumulator has been used for a long time, the internal bladder will leak. In order to ensure the pressure-maintaining effect, it needs to be inflated regularly, which is more troublesome to maintain. Summary of the invention

[0003] In order to solve the deficiencies in the prior art, the present invention provides a self-propelled heavy-load platform leveling hydraulic system and a self-propelled heavy-load platform, which realize the synchronous heavy-load lifting and lowering of multiple leveling units, and the leveling process realizes closed-loop control, thereby improving the adjustment accuracy. At the same time, it realizes stepless adjustment of the heavy-load platform, reduces pressure fluctuations, and thereby improves the stability of the hydraulic shock absorption and reduces the vibration impact on the chassis structure.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] In a first aspect, a self-propelled heavy-load platform leveling hydraulic system is provided, comprising: a hydraulic pump, a multi-way valve and a plurality of leveling units for leveling the upper structural parts of the self-propelled heavy-load platform; each of the leveling units comprises a leveling cylinder control valve group, a leveling cylinder and a leveling cylinder displacement sensor; the outlet of the hydraulic pump is connected to the inlet of the multi-way valve, the working port of the multi-way valve is connected to the inlet of the leveling cylinder control valve group, and the leveling cylinder control valve group is connected to the leveling cylinder; the controller obtains the current state of each leveling cylinder through the leveling cylinder displacement sensor, and controls the extension or retraction of the piston rod of each leveling cylinder through the multi-way valve and the leveling cylinder control valve group according to the set control logic, so as to level the upper structural parts of the self-propelled heavy-load platform.

[0006] Further, the leveling cylinder control valve group includes: a rod chamber balancing valve, the inlet of the rod chamber balancing valve is connected to the working port of the multi-way valve, the outlet of the rod chamber balancing valve is connected to the inlet of the rod chamber balancing valve outlet solenoid valve, and the outlet of the rod chamber balancing valve outlet solenoid valve is connected to the rod chamber of the leveling cylinder; a rodless chamber balancing valve, the inlet of the rodless chamber balancing valve is connected to the working port of the multi-way valve, the outlet of the rodless chamber balancing valve is connected to the inlet of the rodless chamber balancing valve outlet solenoid valve, and the outlet of the rodless chamber balancing valve outlet solenoid valve is connected to the rodless chamber of the leveling cylinder; the rod chamber of the leveling cylinder in each of the leveling units is connected to the rod chamber of the leveling cylinder in other leveling units through the rod chamber connecting electromagnetic ball valve; the rodless chamber of the leveling cylinder in each of the leveling units is connected to the rodless chamber of the leveling cylinder in other leveling units through the rod chamber connecting electromagnetic ball valve.

[0007] Furthermore, the leveling cylinder control valve group also includes: a rod chamber pressure sensor for collecting the pressure of the rod chamber of the leveling cylinder; and a rodless chamber pressure sensor for collecting the pressure of the rodless chamber of the leveling cylinder.

[0008] Furthermore, the leveling cylinder control valve group also includes: a rod chamber inverse proportional relief valve for maintaining the pressure of the rod chamber of the leveling cylinder at no more than a set pressure; and a rodless chamber inverse proportional relief valve for maintaining the pressure of the rodless chamber of the leveling cylinder at no more than a set pressure.

[0009] Furthermore, the control logic includes: multiple leveling units are lifted and lowered synchronously with heavy loads, and the controller obtains the current state of each leveling cylinder through the leveling cylinder displacement sensor and calculates the position average value S of each leveling cylinder. 平均, as the external closed-loop axis, the output of the external closed-loop axis is proportional to the synchronous control target speed of each leveling cylinder; each leveling cylinder and the leveling cylinder displacement sensor matched with the leveling cylinder constitute the internal position closed-loop axis of the leveling cylinder; a virtual axis is added between the external closed-loop axis and the internal position closed-loop axis, the output of the virtual axis and the external closed-loop axis are linked to control, and the position of the internal position closed-loop axis and the virtual axis are linked to control, so as to realize the synchronous extension or synchronous retraction of the leveling cylinders of multiple leveling units, and then realize the synchronous heavy-load lifting of multiple leveling units.

[0010] Furthermore, the control logic includes: for leveling the heavy-loaded platform under the condition of walking on a sloping road, the controller collects the inclination angle data of the upper structure of the heavy-loaded platform, and determines the leveling cylinder that needs to be moved and the movement amplitude according to the collected inclination angle data, and then controls the corresponding leveling cylinder to extend or retract; taking the extension of leveling cylinder one and the retraction of leveling cylinder three as an example: the controller controls the hydraulic pump to supply oil to the rodless cavity of leveling cylinder one through the multi-way valve, and leveling cylinder one extends. The displacement sensor of leveling cylinder one detects the extension position of leveling cylinder one in real time and feeds back to the controller; the controller controls the hydraulic pump to supply oil to the rod cavity of leveling cylinder three through the multi-way valve, and leveling cylinder three retracts. The displacement sensor of leveling cylinder three detects the retracted position of leveling cylinder three in real time and feeds back to the controller.

[0011] Furthermore, the control logic includes: providing steplessly adjustable hydraulic support force for the heavy-loaded platform during walking, the controller opens the electromagnetic ball valve connecting the rodless chamber in each leveling unit, so that the rodless chambers of the leveling cylinders in each leveling unit are connected respectively; synchronous pressurization of the rodless chamber and stepless regulation of the rodless chamber pressure: the controller controls the hydraulic pump to supply oil to the rodless chamber of each leveling cylinder through the multi-way valve, and according to the target pressure value, controls the rodless chamber inverse proportional relief valve in each leveling unit to adjust the pressure in the rodless chamber until the target pressure value is reached; rodless chamber pressure maintenance: the controller detects the pressure value of the rodless chamber through the rodless chamber pressure sensor in each leveling unit. When the pressure value of the rodless chamber is ≤ (target value-1) MPa, the controller controls the hydraulic pump to supplement the oil supply to the rodless chamber of each leveling cylinder through the multi-way valve until the target pressure value is reached, so as to provide steplessly adjustable hydraulic support force for the heavy-loaded platform, and at the same time, realize the function of hydraulic shock absorption to reduce the vibration impact on the crawler chassis structure of the heavy-loaded platform.

[0012] In a second aspect, a self-propelled heavy-load platform is provided, wherein the self-propelled heavy-load platform is equipped with the self-propelled heavy-load platform leveling hydraulic system described in the first aspect.

[0013] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention arranges a hydraulic pump, a multi-way valve and a plurality of leveling units for leveling the upper structural parts of a self-propelled heavy-load platform; each leveling unit comprises a leveling cylinder control valve group, a leveling cylinder and a leveling cylinder displacement sensor; the outlet of the hydraulic pump is connected to the inlet of the multi-way valve, the working port of the multi-way valve is connected to the inlet of the leveling cylinder control valve group, and the leveling cylinder control valve group is connected to the leveling cylinder; the controller obtains the current state of each leveling cylinder through the leveling cylinder displacement sensor, and controls the leveling cylinder according to the set control logic through the multi-way valve, the leveling cylinder control valve group and the leveling cylinder displacement sensor. The control valve group controls the piston rod of each leveling cylinder to extend or retract, which is used to level the upper structure of the self-propelled heavy-duty platform; it realizes the high-precision synchronous heavy-duty lifting and lowering of the leveling cylinder when the upper structure of the heavy-duty platform is initially installed, and realizes the automatic adjustment of the upper structure of the whole machine when the heavy-duty platform is walking on a sloped road; during the walking process of the heavy-duty platform, it provides stepless and adjustable hydraulic support force for the upper load of the heavy-duty platform, and realizes the function of hydraulic shock absorption, reduces the vibration impact on the track chassis structure of the heavy-duty platform, and improves the reliability of the track chassis structure of the heavy-duty platform. The hydraulic principle of this system is reasonable and reliable, with strong versatility, and has reference significance for the design of other similar products. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the principle of a self-propelled heavy-load platform leveling hydraulic system provided by an embodiment of the present invention. Figure 1 ;

[0015] Figure 2 This is a schematic diagram of the principle of a self-propelled heavy-load platform leveling hydraulic system provided by an embodiment of the present invention. Figure 2 ;

[0016] Figure 3 This is a schematic diagram of the principle of a self-propelled heavy-load platform leveling hydraulic system provided by an embodiment of the present invention. Figure 3 ;

[0017] In the figure: 1. Motor; 2. Duplex pump; 3. Front pump; 4. Rear pump; 5. Pilot control valve group; 6. Accumulator; 7. Overflow valve; 8. Solenoid reversing valve; 9. Pressure sensor; 10. Load-sensitive multi-way valve; 11. Rod chamber pressure sensor; 12. Rod chamber connecting solenoid ball valve; 13. Rod chamber balance valve outlet solenoid valve; 14. Rod chamber balance valve; 15. Rod chamber inverse proportional overflow valve; 16. Rodless chamber inverse proportional overflow valve; 17. Rodless chamber balance valve outlet solenoid valve; 18. Rodless chamber balance valve; 19 1. The rodless cavity is connected to the electromagnetic ball valve; 20. The rodless cavity pressure sensor; 21. The control valve group of the leveling cylinder one; 22. The leveling cylinder one; 23. The matching displacement sensor of the leveling cylinder one; 24. The control valve group of the leveling cylinder two; 25. The leveling cylinder two; 26. The matching displacement sensor of the leveling cylinder two; 27. The control valve group of the leveling cylinder three; 28. The leveling cylinder three; 29. ​​The matching displacement sensor of the leveling cylinder three; 30. The control valve group of the leveling cylinder four; 31. The leveling cylinder four; 32. The matching displacement sensor of the leveling cylinder four. DETAILED DESCRIPTION

[0018] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0019] Embodiment 1

[0020] A self-propelled heavy-load platform leveling hydraulic system comprises: a hydraulic pump, a multi-way valve and a plurality of leveling units for leveling the upper structural parts of the self-propelled heavy-load platform; each leveling unit comprises a leveling cylinder control valve group, a leveling cylinder and a leveling cylinder displacement sensor; the outlet of the hydraulic pump is connected to the inlet of the multi-way valve, the working port of the multi-way valve is connected to the inlet of the leveling cylinder control valve group, and the leveling cylinder control valve group is connected to the leveling cylinder; a controller obtains the current state of each leveling cylinder through the leveling cylinder displacement sensor, and controls the piston rod of each leveling cylinder to extend or retract through the multi-way valve and the leveling cylinder control valve group according to the set control logic, so as to level the upper structural parts of the self-propelled heavy-load platform.

[0021] like Figure 1~Figure 3As shown, the present invention mainly includes: a motor 1, a double pump 2, a front pump 3, a rear pump 4, a pilot control valve group 5, an accumulator 6, a relief valve 7, an electromagnetic reversing valve 8, a pressure sensor 9, a load-sensitive multi-way valve 10, a rod chamber pressure sensor 11, a rod chamber connecting electromagnetic ball valve 12, a rod chamber balance valve outlet electromagnetic valve 13, a rod chamber balance valve 14, a rod chamber inverse proportional relief valve 15, a rodless chamber inverse proportional relief valve 16, a rodless chamber balance valve outlet electromagnetic valve 17, a rodless chamber balance valve 18, The rodless chamber is connected to the electromagnetic ball valve 19, the rodless chamber pressure sensor 20, the leveling cylinder one control valve group 21, the leveling cylinder one 22, the leveling cylinder one matching displacement sensor 23, the leveling cylinder two control valve group 24, the leveling cylinder two 25, the leveling cylinder two matching displacement sensor 26, the leveling cylinder three control valve group 27, the leveling cylinder three 28, the leveling cylinder three matching displacement sensor 29, the leveling cylinder four control valve group 30, the leveling cylinder four 31, the leveling cylinder four matching displacement sensor 32.

[0022] The leveling cylinder control valve group includes:

[0023] There is a rod chamber balancing valve 14, the inlet of the rod chamber balancing valve 14 is connected to the working port of the multi-way valve, the outlet of the rod chamber balancing valve 14 is connected to the inlet of the rod chamber balancing valve outlet solenoid valve 13, and the outlet of the rod chamber balancing valve outlet solenoid valve 13 is connected to the rod chamber of the leveling cylinder;

[0024] A rodless chamber balancing valve 18, the inlet of the rodless chamber balancing valve 18 is connected to the working port of the multi-way valve, the outlet of the rodless chamber balancing valve 18 is connected to the inlet of the rodless chamber balancing valve outlet solenoid valve 17, and the outlet of the rodless chamber balancing valve outlet solenoid valve 17 is connected to the rodless chamber of the leveling cylinder;

[0025] The rod chamber is connected to the electromagnetic ball valve 12, and the rod chamber of the leveling oil cylinder in each leveling unit is connected to the rod chamber of the leveling oil cylinder in other leveling units through the rod chamber connecting electromagnetic ball valve 12;

[0026] The rodless cavity is connected to the electromagnetic ball valve 19, and the rodless cavity of the leveling oil cylinder in each leveling unit is connected to the rodless cavity of the leveling oil cylinder in other leveling units through the rodless cavity connecting electromagnetic ball valve 19;

[0027] A rod cavity pressure sensor 11 is used to collect the pressure of the rod cavity of the leveling cylinder;

[0028] The rodless cavity pressure sensor 20 is used to collect the pressure of the rodless cavity of the leveling cylinder;

[0029] The rod chamber inverse proportional relief valve 15 is used to maintain the pressure of the rod chamber of the leveling cylinder not exceeding the set pressure;

[0030] The rodless chamber inverse proportional relief valve 16 is used to maintain the pressure of the rodless chamber of the leveling cylinder not exceeding the set pressure.

[0031] The double pump 2 comprises a front pump 3 and a rear pump 4; in the present invention, the front pump 3 is an electronic variable displacement piston pump, and the rear pump 4 is a pilot gear pump.

[0032] The pilot control valve group 5 includes an accumulator 6, a relief valve 7, an electromagnetic reversing valve 8, and a pressure sensor 9. In the present invention, the electromagnetic reversing valve 8 is a two-position three-way electromagnetic reversing valve.

[0033] Motor 1 drives the rear pump 4 (pilot gear pump) in the duplex pump 2. The pilot pressure is controlled by the relief valve 7. The solenoid reversing valve 8 is not energized, and the pilot pressure oil directly returns to the oil tank and does not participate in the work; the solenoid reversing valve 8 is energized, and the pilot pressure oil is introduced from the outlet of the solenoid reversing valve 8 into the pilot control port G of the front pump 3 to drive the variable mechanism variable of the front pump.

[0034] The first control valve group 21 of the leveling oil cylinder includes a rod chamber pressure sensor 11, a rod chamber connecting electromagnetic ball valve 12, a rod chamber balance valve outlet electromagnetic valve 13, a rod chamber balance valve 14, a rod chamber inverse proportional relief valve 15, a rodless chamber inverse proportional relief valve 16, a rodless chamber balance valve outlet electromagnetic valve 17, a rodless chamber balance valve 18, a rodless chamber connecting electromagnetic ball valve 19, and a rodless chamber pressure sensor 20. The internal components of the second control valve group 24 of the leveling oil cylinder, the third control valve group 27 of the leveling oil cylinder, and the fourth control valve group 30 of the leveling oil cylinder are consistent with those of the first control valve group of the leveling oil cylinder.

[0035] A leveling cylinder one control valve group 21 and a leveling cylinder one matching displacement sensor 23 are installed on the leveling cylinder one 22; a leveling cylinder two control valve group 24 and a leveling cylinder two matching displacement sensor 26 are installed on the leveling cylinder two 25; a leveling cylinder three control valve group 27 and a leveling cylinder three matching displacement sensor 29 are installed on the leveling cylinder three 28; a leveling cylinder four control valve group 30 and a leveling cylinder four matching displacement sensor 32 are installed on the leveling cylinder four 31.

[0036] The load-sensitive multi-way valve 10 in the present invention is a four-way load-sensitive multi-way valve, which is characterized in that each working link is equipped with a pressure compensation valve, and the flow of the A / B port is only in a basically linear positive proportional relationship with the input current of the corresponding pilot valve (Y3a, Y3b, Y4a, Y4b, Y5a, Y5b, Y6a, and Y6b are proportional solenoids corresponding to the pilot proportional pressure reducing valve).

[0037] When the upper structure of the heavy-load platform is initially installed, the high-precision synchronous heavy-load lifting of the four leveling cylinders can be achieved according to the following control logic:

[0038] a. Four-cylinder synchronous heavy-load lifting: The controller starts the motor 1, drives the double pump 2 to work, and the front pump 3 and the rear pump 4 start to supply oil. The electromagnets Y2, Y3a, Y4a, Y5a, Y6a, Y7a, Y8a, Y7b, Y8 b, Y7c, Y8 c, Y7d, and Y8 d are energized, and the leveling cylinder 1 22, the leveling cylinder 25, the leveling cylinder 3 28, and the leveling cylinder 4 31 start to extend outward at the same time. The principle of the four-cylinder synchronous control is shown in item c;

[0039] b. Four-cylinder synchronous heavy-load recovery: The controller starts the motor 1, drives the double pump 2 to work, and the front pump 3 and the rear pump 4 start to supply oil. The electromagnets Y2, Y3b, Y4b, Y5b, Y6b, Y7a, Y8a, Y7b, Y8b, Y7c, Y8c, Y7d, and Y8d are energized to control the leveling cylinder 1 22, the leveling cylinder 25, the leveling cylinder 3 28, and the leveling cylinder 4 31 to start recovery at the same time. The principle of four-cylinder synchronous control is shown in item c;

[0040] c. Principle of four-cylinder synchronous control: 1. The controller uses the average position S of the four leveling cylinders according to the real-time feedback of the displacement sensor 23 of the leveling cylinder 1, the displacement sensor 26 of the leveling cylinder 2, the displacement sensor 29 of the leveling cylinder 3, and the displacement sensor 32 of the leveling cylinder 4. 平均 [S 平均 =(S1+ S2+ S3+ S4) / 4] as the external closed-loop axis, the output of this axis is proportional to the target speed of the four-cylinder synchronous control; 2. The leveling cylinder 1 22 and the matching displacement sensor 23 of the leveling cylinder 1 constitute the internal position closed-loop axis of the leveling cylinder 1 22; the leveling cylinder 2 25 and the matching displacement sensor 26 of the leveling cylinder 2 constitute the internal position closed-loop axis of the leveling cylinder 25; the leveling cylinder 3 28 and the matching displacement sensor 29 of the leveling cylinder 3 constitute the internal position closed-loop axis of the leveling cylinder 3 28; the leveling cylinder 4 31 and the matching displacement sensor 32 of the leveling cylinder 4 constitute the internal position closed-loop axis of the leveling cylinder 4 31; 3. Add a virtual axis between the external closed-loop axis and the internal position closed-loop axis, the output of the virtual axis and the external closed-loop axis are linked to the output control, and the position of the internal position closed-loop axis and the virtual axis are linked to the position control. The outer closed loop axis operates as a typical position control axis, controlling the leveling cylinder 1 22, the leveling cylinder 25, the leveling cylinder 3 28, and the leveling cylinder 4 31 to be implemented in the same position.

[0041] When the heavy-load platform is traveling on a sloped road, the upper structure of the whole machine can be automatically adjusted according to the following control logic:

[0042] a. The dual-axis inclination sensor of the upper structure of the heavy-duty platform can collect the inclination angle data of the upper structure in real time. The inclination angle data is transmitted to the controller, which can: (1) determine which of the leveling cylinders 1 22, 25, 38, and 4 31 needs to be extended and which needs to be retracted; (2) the extension displacement value and the retraction displacement value; (3) control the corresponding cylinder to automatically extend or retract;

[0043] b. Take the extension of leveling cylinder 1 22 and the retraction of leveling cylinder 3 28 as an example: (1) Leveling cylinder 1 22 extends: the controller starts motor 1, drives the double pump 2 to work, and the front pump 3 and the rear pump 4 start to supply oil. Electromagnets Y2, Y3a, Y7a, and Y8a are energized to control the extension of leveling cylinder 1 22. The displacement sensor 23 of leveling cylinder 1 monitors the extension position in real time. After reaching the target position, the displacement signal is transmitted to the controller to control Y3a, Y7a, and Y8a to cut off the power, and the leveling cylinder 1 22 stops extending and maintains the position; (2) Leveling cylinder 3 28 retracts: the controller starts motor 1, drives the double pump 2 to work, and the front pump 3 and the rear pump 4 start to supply oil. Electromagnets Y2, Y5b, Y7c, and Y8c are energized to control the retraction of leveling cylinder No. 3 28. The displacement sensor 29 supporting leveling cylinder No. 3 monitors the retraction position in real time. After reaching the target position, the displacement signal is transmitted to the controller to control Y5b, Y7c, and Y8c to cut off power, and the leveling cylinder No. 3 28 stops retracting and maintains the position.

[0044] When the heavy-load platform is moving, according to the following control logic, it can provide stepless and adjustable hydraulic support force for the upper load of the heavy-load platform, realize the function of hydraulic shock absorption, reduce the vibration impact on the crawler chassis structure of the heavy-load platform, and improve the reliability of the crawler chassis structure of the heavy-load platform;

[0045] a. The rodless chambers of the four leveling cylinders are connected: the controller controls the Y9a, Y9b, Y9c, and Y9d electromagnets to be energized, and controls the rodless chambers of the leveling cylinder 1 22, the leveling cylinder 25, the leveling cylinder 3 28, and the leveling cylinder 4 31 to be connected;

[0046] b. The rodless chambers of the four leveling oil cylinders are pressurized synchronously and the pressure of the rodless chambers is adjusted steplessly: (1) The controller starts the motor 1, drives the double pump 2 to work, and the front pump 3 and the rear pump 4 start to supply oil. The electromagnets Y2, Y3a, Y4a, Y5a, Y6a, Y7a, Y11a, Y7b, Y11b, Y7c, Y11c, Y7d, and Y11d are energized, and the pressure oil is controlled to enter the rodless chambers of the leveling oil cylinder 1 22, the leveling oil cylinder 2 25, the leveling oil cylinder 3 28, and the leveling oil cylinder 4 31 at the same time, and start to pressurize; (2) According to the target pressure value, the controller controls the corresponding inverse proportional relief valves of Y11a, Y11b, Y11c, and Y11d to adjust the pressure and reach the target pressure value;

[0047] c. Pressure maintenance: (1) The controller controls all electromagnets except Y9a, Y9b, Y9c, and Y9d to cut off power, so as to maintain the pressure of the rodless chamber of the four cylinders; (2) The pressure sensors matching the rodless chambers of the leveling oil cylinder 1 22, the leveling oil cylinder 2 25, the leveling oil cylinder 3 28, and the leveling oil cylinder 4 31 monitor the pressure value of the rodless chamber of each leveling oil cylinder in real time. When the pressure value is ≤ (target value - 1) MPa, the controller controls to start the motor 1 again, drive the double pump 2 to work, and the front pump 3 and the rear pump 4 start to supply oil. The electromagnets Y2, Y3a, Y4a, Y5a, Y6a, Y7a, Y11a, Y7b, Y11b, Y7c, Y11c, Y7d, and Y11d are energized, and the pressure oil is controlled to enter the rodless chambers of the leveling oil cylinder 1 22, the leveling oil cylinder 2 25, the leveling oil cylinder 3 28, and the leveling oil cylinder 4 31 at the same time. After reaching the target pressure value, the oil supply is automatically stopped.

[0048] d. Through the above control, the upper load of the heavy-load platform can be provided with steplessly adjustable hydraulic support force, and the function of hydraulic shock absorption can be realized, thereby reducing the vibration impact on the track chassis structure of the heavy-load platform and improving the reliability of the track chassis structure of the heavy-load platform.

[0049] The present invention solves the following problems: (1) the problem of high-precision synchronous heavy-load lifting of four leveling cylinders when the heavy-load platform is initially installed on the upper structural parts of the platform; (2) the problem of automatic adjustment of the upper structural parts of the whole machine when the heavy-load platform is walking on a sloped road; (3) when the heavy-load platform is walking, it provides stepless and adjustable hydraulic support force for the upper load of the heavy-load platform, realizes the function of hydraulic shock absorption, reduces the vibration impact on the crawler chassis structural parts of the heavy-load platform, and improves the reliability of the crawler chassis structure of the heavy-load platform. The hydraulic principle of this system is reasonable and reliable, with strong versatility, and has reference significance for the design of other similar products.

[0050] Embodiment 2

[0051] Based on the self-propelled heavy-load platform leveling hydraulic system described in Example 1, this embodiment provides a self-propelled heavy-load platform, and the self-propelled heavy-load platform is equipped with the self-propelled heavy-load platform leveling hydraulic system described in Example 1.

[0052] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A self-propelled heavy-load platform leveling hydraulic system, characterized in that: include: Hydraulic pumps, multi-way valves and multiple leveling units for leveling the upper structure of the self-propelled heavy-duty platform; Each of the leveling units comprises a leveling cylinder control valve group, a leveling cylinder and a leveling cylinder displacement sensor; The outlet of the hydraulic pump is connected to the inlet of the multi-way valve, the working port of the multi-way valve is connected to the inlet of the leveling oil cylinder control valve group, and the leveling oil cylinder control valve group is connected to the leveling oil cylinder; The controller obtains the current status of each leveling cylinder through the leveling cylinder displacement sensor, and controls the extension or retraction of the piston rod of each leveling cylinder through the multi-way valve and the leveling cylinder control valve group according to the set control logic, which is used to level the upper structure of the self-propelled heavy-load platform.

2. The self-propelled heavy-load platform leveling hydraulic system according to claim 1 is characterized in that: The leveling cylinder control valve group includes: A rod chamber balancing valve (14), the inlet of the rod chamber balancing valve (14) is connected to the working port of the multi-way valve, the outlet of the rod chamber balancing valve (14) is connected to the inlet of the rod chamber balancing valve outlet solenoid valve (13), and the outlet of the rod chamber balancing valve outlet solenoid valve (13) is connected to the rod chamber of the leveling cylinder; A rodless chamber balancing valve (18), the inlet of the rodless chamber balancing valve (18) is connected to the working port of the multi-way valve, the outlet of the rodless chamber balancing valve (18) is connected to the inlet of the rodless chamber balancing valve outlet solenoid valve (17), and the outlet of the rodless chamber balancing valve outlet solenoid valve (17) is connected to the rodless chamber of the leveling cylinder; The rod chamber of the leveling oil cylinder in each leveling unit is connected to the rod chambers of the leveling oil cylinders in other leveling units via a rod chamber connecting electromagnetic ball valve (12); The rodless chamber of the leveling oil cylinder in each leveling unit is connected to the rodless chambers of the leveling oil cylinders in other leveling units via a rodless chamber connecting electromagnetic ball valve (19).

3. The self-propelled heavy-load platform leveling hydraulic system according to claim 2 is characterized in that: The leveling oil cylinder control valve group also includes: A rod cavity pressure sensor (11) is used to collect the pressure of the rod cavity of the leveling oil cylinder; The rodless cavity pressure sensor (20) is used to collect the pressure of the rodless cavity of the leveling oil cylinder.

4. The self-propelled heavy-load platform leveling hydraulic system according to claim 3 is characterized in that: The leveling oil cylinder control valve group also includes: A rod chamber inverse proportional relief valve (15) for maintaining the pressure of the rod chamber of the leveling cylinder not exceeding a set pressure; The rodless chamber inverse proportional relief valve (16) is used to maintain the pressure of the rodless chamber of the leveling cylinder not exceeding the set pressure.

5. The self-propelled heavy-load platform leveling hydraulic system according to claim 4, characterized in that: The control logic includes: multiple leveling units synchronously lifting heavy loads, The controller obtains the current state of each leveling cylinder through the leveling cylinder displacement sensor and calculates the average position S of each leveling cylinder. 平均 , as an external closed-loop axis, the output of the external closed-loop axis is proportional to the synchronous control target speed of each leveling cylinder; Each leveling cylinder and the leveling cylinder displacement sensor matched with the leveling cylinder constitute the internal position closed loop axis of the leveling cylinder; A virtual axis is added between the external closed-loop axis and the internal position closed-loop axis. The output of the virtual axis and the external closed-loop axis are controlled in linkage, and the position of the internal position closed-loop axis and the virtual axis are controlled in linkage, so that the leveling cylinders of multiple leveling units can be extended or retracted synchronously, thereby realizing the synchronous heavy-load lifting of multiple leveling units.

6. The self-propelled heavy-load platform leveling hydraulic system according to claim 4, characterized in that: The control logic includes: leveling the heavy-load platform under the condition of walking on a sloped road, The controller collects the tilt angle data of the upper structure of the heavy-load platform, and determines the leveling cylinder that needs to be moved and the movement amplitude according to the collected tilt angle data, and then controls the corresponding leveling cylinder to extend or retract; Take the extension of leveling cylinder 1 (22) and the retraction of leveling cylinder 3 (28) as an example: the controller controls the hydraulic pump to supply oil to the rodless chamber of leveling cylinder 1 (22) through the multi-way valve, and the leveling cylinder 1 (22) is extended. The displacement sensor (23) of leveling cylinder 1 detects the extension position of leveling cylinder 1 (22) in real time and feeds back to the controller; the controller controls the hydraulic pump to supply oil to the rod chamber of leveling cylinder 3 (28) through the multi-way valve, and the leveling cylinder 3 (28) is retracted. The displacement sensor (29) of leveling cylinder 3 detects the retracted position of leveling cylinder 3 (28) in real time and feeds back to the controller.

7. The self-propelled heavy-load platform leveling hydraulic system according to claim 4, characterized in that: The control logic includes: providing a stepless and adjustable hydraulic support force for the heavy-load platform during the walking process, The controller opens the rodless cavity communication electromagnetic ball valve (19) in each leveling unit, so that the rodless cavities of the leveling cylinders in each leveling unit are connected respectively; Synchronous pressurization of the rodless chamber and stepless regulation of the rodless chamber pressure: the controller controls the hydraulic pump to supply oil to the rodless chamber of each leveling cylinder through the multi-way valve, and controls the rodless chamber inverse proportional relief valve (16) in each leveling unit to adjust the pressure in the rodless chamber according to the target pressure value until the target pressure value is reached; Rodless cavity pressure maintenance: The controller detects the pressure value of the rodless cavity through the rodless cavity pressure sensor (20) in each leveling unit. When the pressure value of the rodless cavity is ≤ (target value - 1) MPa, the controller controls the hydraulic pump to replenish oil to the rodless cavity of each leveling cylinder through the multi-way valve until the target pressure value is reached, so as to provide stepless adjustable hydraulic support force for the heavy-load platform and realize the function of hydraulic shock absorption to reduce the vibration impact on the crawler chassis structure of the heavy-load platform.

8. A self-propelled heavy-load platform, characterized in that: The self-propelled heavy-load platform is equipped with the self-propelled heavy-load platform leveling hydraulic system according to any one of claims 1 to 7.

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