Simulation analysis method for oil-gas suspension system of middle rear axle unilateral connection

Abstract

The application discloses a simulation analysis method for a middle-rear axle single-side joint oil-gas suspension system, and comprises the following steps: S1, obtaining the strokes of a middle axle oil cylinder and a rear axle oil cylinder in the middle-rear axle single-side joint oil-gas suspension system under multiple working conditions respectively, and obtaining the stroke change curve of each working condition by taking the stroke of one of the oil cylinders as the horizontal coordinate and the stroke of the other oil cylinder as the vertical coordinate for each working condition; and S2, building an equivalent simulation model of the middle-rear axle single-side joint oil-gas suspension system according to the structure of the middle-rear axle single-side joint oil-gas suspension system, inputting the stroke change curve obtained in S1 into the built equivalent simulation model, and obtaining the oil cylinder force change distribution curve of the middle axle oil cylinder and / or the rear axle oil cylinder. The application has the beneficial effect that the oil cylinder force change distribution curve of the middle-rear joint suspension system under different working conditions can be accurately obtained, and a model basis is provided for the design of the oil cylinder stroke of the suspension system, suspension motion analysis and stress analysis.

Description

Technical Field

[0001] This invention relates to the field of hydropneumatic suspension design methods. More specifically, this invention relates to a simulation analysis method for a single-sided hydropneumatic suspension system with a central and rear axle connection. Background Technology

[0002] Mining dump trucks equipped with full hydropneumatic suspension systems are widely used in the mining industry in China. Hydropneumatic suspensions offer variable stiffness and damping characteristics, resulting in low suspension stiffness, low frequency of rotation, and good comfort when the vehicle is unloaded. When fully loaded, its high stiffness meets the requirements for heavy-duty loads while also considering frequency of rotation and comfort, reducing driver fatigue. It also ensures smooth vehicle operation, reducing bumps caused by road surface disturbances and improving overall vehicle reliability and lifespan. The hydropneumatic suspension system used in mining dump trucks, with its single-sided connection between the middle and rear axles, features an external high- and low-pressure accumulator structure. The stiffness of the suspension is determined by the total volume of oil entering the accumulator from the middle and rear axle cylinders. Therefore, any change in the stroke of either the middle or rear axle cylinder will affect the amount of oil entering the accumulator, thus altering the stiffness of the suspension system. When developing suspension systems, design engineers often use hydropneumatic suspension stiffness calculation formulas to initially determine the suspension stiffness curves for the parallel wheel hop of the middle and rear axles, in order to obtain the static deflection parameters (travel under no-load and full-load conditions). However, the operating environment of mining dump trucks is extremely harsh, with uneven road surfaces being very common. The travel variation of the middle and rear axle suspension is unpredictable, making it difficult to determine the real-time suspension stiffness. The impact of the suspension on the entire vehicle is difficult to evaluate through theoretical calculations. In practice, insufficient cylinder travel leads to cylinder overshoot or bottoming out, and small cylinder sizes result in low stiffness and poor driving stability. How to establish a calculation model for a single-sided connected hydropneumatic suspension system for the middle and rear axles, obtain accurate suspension stiffness characteristics, and thus rationally match the suspension system scheme to reduce cylinder overshoot or bottoming-out failures, and further analyze the impact of suspension performance on the overall vehicle driving stability, is an important problem that needs to be solved in the design of mining dump trucks. Summary of the Invention

[0003] One object of the present invention is to solve at least the above-mentioned problems and to provide at least the advantages that will be described later.

[0004] Another objective of this invention is to provide a simulation analysis method for a single-sided connected hydraulic suspension system for the middle and rear axles. This method can accurately derive the cylinder force variation distribution curves of the middle and rear connected suspension system under different working conditions, providing a model basis for designing cylinder stroke, suspension motion analysis, and force analysis of the suspension system. This can increase the success rate of suspension system design, thereby reducing suspension system malfunctions and improving the overall vehicle driving stability.

[0005] To achieve these objectives and other advantages according to the present invention, a simulation analysis method for a single-sided connected hydro-pneumatic suspension system for the middle and rear axles is provided, comprising the following steps:

[0006] S1. Obtain the corresponding strokes of the middle axle cylinder and the rear axle cylinder in the single-sided connected oil-pneumatic suspension system of the middle and rear axles under various working conditions. For each working condition, take the stroke of one cylinder as the horizontal axis and the stroke of the other cylinder as the vertical axis to obtain the stroke change curve under each working condition.

[0007] S2. Based on the structure of the single-sided connected oil-pneumatic suspension system of the middle and rear axles, an equivalent simulation model of the single-sided connected oil-pneumatic suspension of the middle and rear axles is built. The stroke change curve obtained in S1 is input into the built equivalent simulation model to obtain the cylinder force change distribution curve of the middle axle cylinder and / or the rear axle cylinder.

[0008] Preferably, the single-sided connected hydropneumatic suspension system for the middle and rear axles includes a middle axle cylinder, a rear axle cylinder, an accumulator, and a pair of connecting pipes. The piston rods of both the middle axle cylinder and the rear axle cylinder are provided with one-way valves and damping holes. The accumulator includes a cavity, in which a pair of sliding sealing plugs are spaced apart to divide the cavity into a low-pressure air chamber, a hydraulic chamber, and a high-pressure air chamber. The hydraulic chamber is connected to the rodless chambers of the middle axle cylinder and the rear axle cylinder respectively through a pair of connecting pipes.

[0009] Preferably, the equivalent simulation model built in step S2 includes an equivalent element group of the middle axle cylinder, an equivalent element group of the rear axle cylinder, an equivalent element group of the accumulator, a pair of connecting pipeline elements, a displacement excitation element of the middle axle cylinder, and a displacement excitation element of the rear axle cylinder.

[0010] The equivalent element group of the middle bridge cylinder includes a rod-side chamber element, a rodless chamber element, a damping orifice element, a check valve element, a check valve stroke limiting element, a rodless chamber variable volume oil element, a rod-side variable volume oil element, and a cylinder stroke limiting element. The rodless chamber element is connected to the rodless chamber variable volume oil element, the cylinder stroke limiting element, and the rod-side chamber element. The rod-side chamber element is connected to the rod-side variable volume oil element and the middle bridge cylinder displacement excitation element. The damping orifice element and the check valve element are both connected between the rod-side variable volume oil element and the rodless chamber variable volume oil element. The check valve element is connected to the check valve stroke limiting element.

[0011] The structure of the equivalent element group of the rear axle cylinder is the same as that of the equivalent element group of the middle axle cylinder;

[0012] The accumulator equivalent element group includes a low-pressure gas chamber element, a low-pressure gas chamber stroke limiting element, a low-pressure rodless hydraulic chamber element, a low-pressure gas variable volume element, a high-pressure gas chamber element, a high-pressure gas chamber stroke limiting element, a high-pressure rodless hydraulic chamber element, a high-pressure gas variable volume element, and an accumulator oil variable volume element. The low-pressure gas chamber element is connected to the low-pressure gas variable volume element and the low-pressure gas chamber stroke limiting element, and the low-pressure gas chamber stroke limiting element is connected to the low-pressure rodless hydraulic chamber element. The high-pressure gas chamber element is connected to the high-pressure gas variable volume element and the high-pressure gas chamber stroke limiting element, and the high-pressure gas chamber stroke limiting element is connected to the high-pressure rodless hydraulic chamber element. The low-pressure rodless hydraulic chamber element and the high-pressure rodless hydraulic chamber element are both connected to the accumulator oil variable volume element.

[0013] Among them, a pair of connecting pipe elements correspond to the rodless cavity elements in the equivalent element group of the middle axle cylinder and the equivalent element group of the rear axle cylinder, respectively. One end of the connecting pipe element is connected to the corresponding rodless cavity element, and the other end is connected to the variable volume element of the accumulator oil. The displacement excitation element of the middle axle cylinder is connected to the rod cavity element in the equivalent element group of the middle axle cylinder, and the displacement excitation element of the rear axle cylinder is connected to the rod cavity element in the equivalent element group of the rear axle cylinder.

[0014] Preferably, the equivalent simulation model also includes a force sensor element for the middle axle cylinder and a force sensor element for the rear axle cylinder. The equivalent element group for the middle axle cylinder also includes a pressure sensor element for the rodless chamber of the middle axle cylinder. The equivalent element group for the rear axle cylinder also includes a pressure sensor element for the rodless chamber of the rear axle cylinder. The equivalent element group for the accumulator also includes a high-pressure sensor element and a low-pressure sensor element.

[0015] Specifically, the rodless chamber pressure sensor element of the middle axle cylinder is connected to the rodless chamber oil variable volume element of the equivalent element group of the middle axle cylinder; the rodless chamber pressure sensor element of the rear axle cylinder is connected to the rodless chamber oil variable volume element of the equivalent element group of the rear axle cylinder; the high-pressure pressure sensor element is connected to the high-pressure gas variable volume element; the low-pressure pressure sensor element is connected to the low-pressure gas variable volume element; the force sensor element of the middle axle cylinder is connected to the rod chamber element in the equivalent element group of the middle axle cylinder; and the force sensor element of the rear axle cylinder is connected to the rod chamber element in the equivalent element group of the rear axle cylinder.

[0016] Preferably, the multiple working conditions include five working conditions: parallel wheel jump, asymmetrical parallel wheel jump, single wheel jump, asymmetrical reverse wheel jump, and reverse wheel jump.

[0017] Preferably, the method for obtaining the corresponding strokes of the middle axle cylinder and rear axle cylinder in the single-sided connected hydraulic suspension system under the five working conditions of parallel wheel hop, asymmetrical parallel wheel hop, single wheel hop, asymmetrical reverse wheel hop, and reverse wheel hop is as follows:

[0018] A1. Let S be the compression stroke of the middle axle cylinder / rear axle cylinder under no-load conditions. 空上 The tension stroke under no-load conditions is denoted as S. 空下 The compression stroke under full load is denoted as S. 满上 The tensile stroke under full load is denoted as S. 满下 Let L be the static deflection of the middle axle cylinder / rear axle cylinder from no-load state to full-load state, then S 空上 =S 满上 +L, S 空下 =S 满下 -L;

[0019] A2. Under full load, the stroke calculation methods for the middle axle cylinder and the rear axle cylinder under five different working conditions are as follows:

[0020] Under parallel wheel runout conditions: S-axis of the middle axle cylinder and the rear axle cylinder 满上 The values ​​are all min(a, c / 2), S 满下 The values ​​are all -[min(b, d / 2)];

[0021] Under asymmetrical parallel wheel jump conditions: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, c / 2), S 满下 The value is -[min(b, d / 2)], and the S value of the other cylinder is... 满上 The value is 0.5*min(a, c / 2), S 满下 The value is -[0.5*min(b, d / 2)];

[0022] Under single-wheel jump condition: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, c) and S. 满下 The value is -[min(b, d)], and the S of the other cylinder is... 满上 The values ​​are 0 and S. 满下 The value is 0;

[0023] Under asymmetrical reverse wheel runout conditions: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, b) and S. 满下 The value is -[min(a, b)], and the S of the other cylinder is... 满上 The value is -[0.5*min(a, b)], S 满下The value is 0.5*min(a, b);

[0024] Under reverse wheel runout conditions: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, b) and S. 满下 The value is -[min(a, b)], and the S of the other cylinder is... 满上 The value is -[min(a, b)], S 满下 The value is min(a, b);

[0025] Where a is the length of the rodless chamber of the cylinder under full load, b is the length of the rod chamber of the cylinder under full load, c is the total gas volume of the high-pressure chamber and the low-pressure chamber under full load / the area difference between the rodless chamber and the rod chamber of the cylinder, and d is the total oil chamber volume of the high-pressure chamber and the low-pressure chamber under full load / the area difference between the rodless chamber and the rod chamber of the cylinder.

[0026] Preferably, the parameter settings of the rod-type chamber element and the rodless chamber element both include piston diameter, piston rod diameter, and chamber length; the parameter settings of the rod-type chamber variable volume liquid element and the rodless chamber variable volume liquid element both include initial pressure and dead zone volume; the parameter settings of the damping orifice element include damping orifice diameter; the parameter settings of the one-way valve element include base diameter and steel ball diameter; the parameter settings of the one-way valve stroke limiting element include the maximum displacement limit and minimum displacement limit of the steel ball; and the parameter settings of the cylinder stroke limiting element include the upper displacement limit and lower displacement limit of the cylinder.

[0027] Preferably, the parameter settings of the low-pressure gas chamber element and the high-pressure gas chamber element all include piston diameter, piston rod diameter, and gas chamber length; the parameter settings of the low-pressure gas variable volume element, the high-pressure gas variable volume element, and the accumulator oil variable volume element all include initial pressure and dead zone volume; the parameter settings of the low-pressure gas chamber stroke limiting element and the high-pressure gas chamber stroke limiting element include gas compression displacement limit and gas tension displacement limit; the parameter settings of the low-pressure rodless hydraulic chamber element include piston diameter, piston rod diameter, and low-pressure hydraulic chamber length; and the parameter settings of the high-pressure rodless hydraulic chamber element include piston diameter, piston rod diameter, and high-pressure hydraulic chamber length.

[0028] Preferably, the parameter settings for the connecting pipeline components include the inner diameter of the pipeline cavity, the length of the pipeline, the pressure of the pipeline, and the wall thickness of the pipeline.

[0029] The present invention has at least the following beneficial effects:

[0030] This invention provides a simulation analysis method for a single-sided connected hydraulic suspension system for the middle and rear axles. It breaks down all the complex working conditions of mining dump trucks traveling on uneven mining roads into typical working conditions, obtaining the suspension travel range under each typical working condition. Furthermore, through the simulation model, the distribution curves of the hydraulic cylinder force variation under different working conditions of the middle and rear connected suspension system can be accurately obtained. This provides a model basis for designing the hydraulic cylinder travel, analyzing suspension motion, and performing force analysis. Applying the method provided by this invention can increase the success rate of suspension system design, reduce suspension system malfunctions, and improve the overall vehicle driving stability.

[0031] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of the single-sided oil-gas suspension system for the middle and rear axles according to one of the technical solutions of the present invention;

[0033] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0034] Figure 3 This is a schematic diagram of the equivalent simulation model structure of the single-sided connected oil-gas suspension system of the middle and rear axles according to one of the technical solutions of the present invention;

[0035] Figure 4 The graph shows the stroke distribution curves of the middle axle cylinder and the rear axle cylinder under five typical working conditions in Embodiment 1 of the present invention. The horizontal axis represents the displacement of the middle axle cylinder, and the vertical axis represents the displacement of the rear axle cylinder.

[0036] Figure 5 This is a simulation curve of the force distribution of the middle axle cylinder obtained in Embodiment 1 of the present invention;

[0037] Figure 6 This is a comparison diagram of the simulation model and the measured cylinder force distribution curve of the middle axle cylinder in Embodiment 1 of the present invention. In the figure, the horizontal axis represents the displacement of the middle axle cylinder, and the vertical axis represents the force of the middle axle cylinder.

[0038] Figure 7 This is the time-displacement curve of the middle bridge cylinder described in one of the technical solutions of the present invention.

[0039] Reference numerals: 100-Middle axle cylinder; 1001-Middle axle cylinder rodless chamber; 1002-Middle axle cylinder rod chamber; 1003-Middle axle cylinder piston rod; 1004-Middle axle cylinder check valve; 1005-Middle axle cylinder damping orifice; 200-Accumulator; 2001-Low-pressure chamber; 2002-High-pressure chamber; 2003-Hydraulic chamber; 300-Rear axle cylinder; 3001-Rear axle cylinder rodless chamber; 3002-Rear axle cylinder rod chamber; 400-Connecting pipeline;

[0040] 1-Rod chamber element of the middle axle cylinder; 2-Rodless chamber element of the middle axle cylinder; 3-Damping orifice element of the middle axle cylinder; 4-Check valve element of the middle axle cylinder; 5-Pressure sensor element of the rodless chamber of the middle axle cylinder; 6-Variable volume element of the rodless chamber oil of the middle axle cylinder; 7-Rod chamber element of the rear axle cylinder; 8-Rodless chamber element of the rear axle cylinder; 9-Damping orifice element of the rear axle cylinder; 10-Check valve element of the rear axle cylinder; 11-Pressure sensor element of the rodless chamber of the rear axle cylinder; 12-Variable volume element of the rodless chamber oil of the rear axle cylinder; 13-First connecting pipeline element; 14-Second connecting pipeline element; 15-Low-pressure gas chamber element; 16-Low-pressure rodless hydraulic chamber element; 17-Low-pressure pressure sensor element; 18-Variable volume element of low-pressure gas; 19- 20-High-pressure air chamber element; 21-High-pressure rodless hydraulic chamber element; 22-High-pressure pressure sensor element; 23-High-pressure gas variable volume element; 24-Middle axle cylinder force sensor element; 25-Rear axle cylinder force sensor element; 26-Rear axle cylinder displacement excitation element; 27-Middle axle cylinder stroke limit element; 28-Middle axle cylinder check valve stroke limit element; 29-Low-pressure air chamber stroke limit element; 30-Accumulator oil variable volume element; 31-Rear axle cylinder rod chamber oil variable volume element; 32-Rear axle cylinder check valve stroke limit element; 33-Rear axle cylinder stroke limit element; 34-Middle axle cylinder rod chamber oil variable volume element; 35-High-pressure air chamber stroke limit element. Detailed Implementation

[0041] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0042] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0043] like Figure 1-7 As shown, this invention provides a simulation analysis method for a single-sided connected oil-gas suspension system for the middle and rear axles, comprising the following steps:

[0044] S1. Obtain the corresponding strokes of the middle axle cylinder and the rear axle cylinder in the single-sided connected oil-pneumatic suspension system of the middle and rear axles under various working conditions. For each working condition, take the stroke of one cylinder as the horizontal axis and the stroke of the other cylinder as the vertical axis to obtain the stroke change curve under each working condition.

[0045] S2. Based on the structure of the single-sided connected oil-gas suspension system of the middle and rear axles, an equivalent simulation model of the single-sided connected oil-gas suspension of the middle and rear axles is built. The stroke change curve obtained in S1 is input into the built equivalent simulation model to obtain the cylinder force change distribution curve of the middle axle cylinder and / or the rear axle cylinder.

[0046] In the above technical solution, mining dump trucks will experience a variety of working conditions during actual operation. This invention first obtains the cylinder strokes of the middle axle cylinder and the rear axle cylinder in the single-sided connected oil-pneumatic suspension system of the middle and rear axles under different working conditions. Specifically, for any working condition, multiple one-to-one corresponding strokes of the middle axle cylinder and the rear axle cylinder are obtained. The stroke of one cylinder (such as the middle axle cylinder) is used as the horizontal axis and the stroke of the other cylinder (such as the rear axle cylinder) is used as the vertical axis to draw the stroke change curve of a pair of cylinders, which is the stroke change curve under that working condition. By obtaining the stroke change curves under different working conditions in sequence, multiple stroke change curves can be obtained. These multiple stroke change curves are used as input parameters for subsequent simulation calculations.

[0047] In the simulation calculation and analysis process, firstly, based on the structure of the single-sided connected hydraulic-pneumatic suspension system of the middle and rear axles to be designed, an equivalent simulation model of the system is built in simulation software such as Amesim. During the simulation model operation, the multiple stroke variation curves obtained above are used as input parameters. Specifically, since any point on the stroke variation curve represents the stroke displacement of the middle axle cylinder and the rear axle cylinder under that working condition, the entire stroke variation curve reflects the entire stroke displacement of the middle axle cylinder and the rear axle cylinder under that working condition. The stroke variation curve can be used as the stroke input source for the middle axle cylinder and the rear axle cylinder to simulate their strokes. The stroke variation curve corresponding to each point of the middle axle cylinder and the corresponding stroke of the rear axle cylinder are input into the simulation model. The simulation model runs and calculates to obtain the cylinder force variation distribution curve of the middle axle cylinder and / or the rear axle cylinder under this working condition. Designers refer to the obtained cylinder force variation distribution curve to design the air suspension, thereby increasing the success rate of suspension system design.

[0048] The beneficial effects of this technical solution are as follows: by obtaining the strokes of the middle axle cylinder and the rear axle cylinder in a single-sided connected hydraulic-pneumatic suspension system under various working conditions, and simultaneously, based on the structure of the single-sided connected hydraulic-pneumatic suspension system, an equivalent simulation model of the single-sided connected hydraulic-pneumatic suspension system can be built. The obtained strokes of the middle axle cylinder and the rear axle cylinder are input as input parameters into the equivalent simulation model. By running the equivalent simulation model for calculation, the variation distribution curves of the cylinder force of the middle axle cylinder and / or the rear axle cylinder under different working conditions of the single-sided connected suspension system can be accurately obtained. This provides a model basis for designing cylinder stroke, analyzing suspension motion, and performing force analysis for the suspension system. Applying the method provided by this invention can increase the success rate of suspension system design, reduce suspension system malfunctions, and improve the overall vehicle driving stability.

[0049] In another technical solution, the single-sided connected oil-pneumatic suspension system of the middle and rear axles includes a middle axle cylinder 100, a rear axle cylinder 300, an accumulator 200, and a pair of connecting pipes 400. The piston rods of the middle axle cylinder 100 and the rear axle cylinder 300 are provided with one-way valves and damping holes. The accumulator 200 includes a cavity, and a pair of sliding sealing plugs are spaced apart in the cavity to divide the cavity into a low-pressure air chamber 2001, a hydraulic chamber 2003, and a high-pressure air chamber 2002 in sequence. The hydraulic chamber 2003 is connected to the rodless chambers of the middle axle cylinder 100 and the rear axle cylinder 300 respectively through a pair of connecting pipes 400.

[0050] In the above technical solutions, such as Figures 1-2 As shown, the single-sided connected hydropneumatic suspension system for the middle and rear axles includes a middle axle cylinder 100, a rear axle cylinder 300, an accumulator 200, and a pair of connecting pipes 400. The middle axle cylinder 100 and the rear axle cylinder 300 have the same structure. Specifically, the middle axle cylinder 100 includes a vertical cylinder body, and a piston rod 1003 is provided inside the cylinder body to divide the cylinder body into a rodless chamber 1001 and a rod chamber 1002. The rod chamber 1002 of the middle axle cylinder is the cylinder body where the piston rod 1003 of the middle axle cylinder is located. The piston rod 1003 of the middle axle cylinder is provided with a one-way valve 1004 and a damping hole 1005. Both the rod chamber 1002 and the rodless chamber 1001 of the middle axle cylinder are completely filled with hydraulic oil. The one-way valve 1004 of the middle axle cylinder allows the hydraulic oil in the rodless chamber 1001 of the middle axle cylinder to flow into the rod chamber 1002 of the middle axle cylinder.

[0051] The rear axle cylinder 300 includes a vertical cylinder body. A piston rod is provided within the cylinder body to divide it into a rodless chamber 3001 and a rod chamber 3002. The rod chamber 3002 is where the piston rod is located. A one-way valve and a damping orifice are provided on the piston rod. Both the rod chamber 3002 and the rodless chamber 3001 are completely filled with hydraulic oil. The one-way valve allows hydraulic oil from the rodless chamber to flow into the rod chamber 3002.

[0052] The accumulator 200 includes a cavity, in which a pair of sliding sealing plugs are spaced apart to divide the cavity into a low-pressure gas chamber 2001, a hydraulic chamber 2003, and a high-pressure gas chamber 2002. The low-pressure gas chamber 2001 is filled with low-pressure gas, the high-pressure gas chamber 2002 is filled with high-pressure gas, and the hydraulic chamber 2003 is filled with hydraulic oil. The hydraulic chamber 2003 is connected to the rodless chamber 1001 of the middle axle cylinder and the rodless chamber 3001 of the rear axle cylinder through a pair of connecting pipes 400, which are hydraulic pipes.

[0053] In this technical solution, the working principle of the single-sided connected hydropneumatic suspension system for the middle and rear axles is as follows: When both the middle axle cylinder 100 and the rear axle cylinder 300 are in a compressed state, the rodless chambers of both the middle axle cylinder 100 and the rear axle cylinder 300 are compressed. Part of the oil in the rodless chambers of the middle axle cylinder 100 and the rear axle cylinder 300 enters the rod chamber 1002 of the middle axle cylinder and the rod chamber of the rear axle cylinder 300, respectively, while the other part enters the hydraulic chamber of the accumulator 200 through the corresponding connecting pipes 400. At point 2003, the volume of the hydraulic chamber 2003 of the accumulator 200 increases, compressing the low-pressure chamber 2001 (when the pressure of the low-pressure chamber 2001 increases to the same level as the pressure of the high-pressure chamber 2002, the hydraulic oil in the accumulator 200 will simultaneously compress both the low-pressure chamber 2001 and the high-pressure chamber 2002). The pressure in the hydraulic chamber 2003 of the accumulator 200 is the same as the pressure in the rodless chamber of the middle axle cylinder 100 and the rodless chamber of the rear axle cylinder 300, according to the adiabatic gas compression equation P1V1. r =P2V2 rIt can be deduced that the suspension system pressure is inversely proportional to the volume of the air chambers; the greater the compression stroke of the middle and rear axles, the greater the suspension system pressure. When both the middle and rear axle cylinders 300 are in the rebound state, the rodless chamber 1001 of the middle axle cylinder and the rodless chamber 3001 of the rear axle cylinder are stretched. Part of the oil comes from the rod chambers of the middle axle cylinder 100 and the rear axle cylinder 300, and the other part comes from the hydraulic chamber 2003 of the accumulator 200. At this time, the volume of the hydraulic chamber 2003 of the accumulator 200 decreases, and the volume of the low-pressure air chamber 2001 increases (when the pressure of the low-pressure air chamber 2001 is less than that of the high-pressure air chamber 2002) or the volumes of both the high-pressure air chamber 2002 and the low-pressure air chamber 2001 increase (when the pressures of the low-pressure air chamber 2001 and the high-pressure air chamber 2002 are the same). Therefore, the greater the stretching stroke of the middle and rear axles, the lower the suspension system pressure.

[0054] The beneficial effect of adopting the above technical solution is that, by designing the middle axle cylinder 100, the rear axle cylinder 300, the accumulator 200, and a pair of connecting pipes 400, a single-sided connected oil-air suspension structure for the middle and rear axles is provided. The simulation analysis method of the present invention is more suitable for the simulation analysis of the single-sided connected oil-air suspension structure for the middle and rear axles with this structure.

[0055] In another technical solution, the equivalent simulation model built in step S2 includes the equivalent element group of the middle axle cylinder, the equivalent element group of the rear axle cylinder, the equivalent element group of the accumulator, a pair of connecting pipeline elements, the displacement excitation element 25 of the middle axle cylinder, and the displacement excitation element 26 of the rear axle cylinder.

[0056] The equivalent element group of the middle bridge cylinder includes a rod-side chamber element, a rodless chamber element, a damping orifice element, a check valve element, a check valve stroke limiting element, a rodless chamber variable volume oil element, a rod-side variable volume oil element, and a cylinder stroke limiting element. The rodless chamber element is connected to the rodless chamber variable volume oil element, the cylinder stroke limiting element, and the rod-side chamber element. The rod-side chamber element is connected to the rod-side variable volume oil element and the middle bridge cylinder displacement excitation element 25. The damping orifice element and the check valve element are both connected between the rod-side variable volume oil element and the rodless chamber variable volume oil element. The check valve element is connected to the check valve stroke limiting element.

[0057] The structure of the equivalent element group of the rear axle cylinder is the same as that of the equivalent element group of the middle axle cylinder;

[0058] The accumulator equivalent element group includes a low-pressure gas chamber element 15, a low-pressure gas chamber stroke limiting element 29, a low-pressure rodless hydraulic chamber element 16, a low-pressure gas variable volume element 18, a high-pressure gas chamber element 19, a high-pressure gas chamber stroke limiting element, a high-pressure rodless hydraulic chamber element 20, a high-pressure gas variable volume element 22, and an accumulator oil variable volume element 30. The low-pressure gas chamber element 15 is connected to the low-pressure gas variable volume element 18 and the low-pressure gas chamber stroke limiting element 29. The low-pressure gas chamber stroke limiting element 29 is connected to the low-pressure rodless hydraulic chamber element 16. The high-pressure gas chamber element 19 is connected to the high-pressure gas variable volume element 22 and the high-pressure gas chamber stroke limiting element. The high-pressure gas chamber stroke limiting element is connected to the high-pressure rodless hydraulic chamber element 20. The low-pressure rodless hydraulic chamber element 16 and the high-pressure rodless hydraulic chamber element 20 are both connected to the accumulator oil variable volume element 30.

[0059] Among them, a pair of connecting pipe elements correspond to the rodless cavity elements in the equivalent element group of the middle axle cylinder and the equivalent element group of the rear axle cylinder, respectively. One end of the connecting pipe element is connected to the corresponding rodless cavity element, and the other end is connected to the accumulator oil variable volume element 30. The displacement excitation element 25 of the middle axle cylinder is connected to the rod cavity element in the equivalent element group of the middle axle cylinder, and the displacement excitation element 26 of the rear axle cylinder is connected to the rod cavity element in the equivalent element group of the rear axle cylinder.

[0060] In the above technical solution, specifically, the equivalent simulation model built in step S2 includes the equivalent element group of the middle axle cylinder, the equivalent element group of the rear axle cylinder, the equivalent element group of the accumulator, a pair of connecting pipeline elements, the displacement excitation element 25 of the middle axle cylinder, the displacement excitation element 26 of the rear axle cylinder, and the pair of connecting pipeline elements are the first connecting pipeline element 13 and the second connecting pipeline element 14.

[0061] The equivalent element group of the middle bridge cylinder includes a rod chamber element 1, a rodless chamber element 2, a damping orifice element 3, a one-way valve element 4, a one-way valve stroke limit element 28, a rodless chamber oil variable volume element 6, a rod chamber oil variable volume element 34, and a stroke limit element 27.

[0062] The force-bearing port of the stroke limiting element 27 of the middle bridge cylinder is connected to the force-bearing port of the rodless cavity element 2 of the middle bridge cylinder. The inlet and outlet of the rodless cavity element 2 of the middle bridge cylinder is connected to the first inlet and outlet of the variable volume oil element 6 of the rodless cavity of the middle bridge cylinder. The force-bearing port of the rodless cavity element 2 of the middle bridge cylinder is connected to the force-bearing port of the rod cavity element 1 of the middle bridge cylinder. The inlet and outlet of the rod cavity element 1 of the middle bridge cylinder is connected to the first inlet and outlet of the variable volume oil element 34 of the rod cavity of the middle bridge cylinder.

[0063] Specifically, the inlet of the damping orifice element 3 of the middle bridge cylinder is connected to the second inlet / outlet of the rodless chamber oil variable volume element 6 of the middle bridge cylinder, and the outlet of the damping orifice element 3 of the middle bridge cylinder is connected to the second inlet / outlet of the rod chamber oil variable volume element 34 of the middle bridge cylinder; the inlet of the one-way valve element 4 of the middle bridge cylinder is connected to the second inlet / outlet of the rodless chamber oil variable volume element 6 of the middle bridge cylinder, and the outlet of the one-way valve element 4 of the middle bridge cylinder is connected to the second inlet / outlet of the rod chamber oil variable volume element 34 of the middle bridge cylinder; the first force-applying port of the one-way valve stroke limiting element 28 of the middle bridge cylinder is connected to the force-receiving port of the one-way valve element 4 of the middle bridge cylinder;

[0064] The force-bearing port of the rear axle cylinder stroke limiting element 33 is connected to the force-bearing port of the rodless chamber element 8 of the rear axle cylinder. The inlet and outlet of the rodless chamber element 8 of the rear axle cylinder is connected to the first inlet and outlet of the rodless chamber oil variable volume element 12 of the rear axle cylinder. The force-bearing port of the rodless chamber element 8 of the rear axle cylinder is connected to the force-bearing port of the rod chamber element 7 of the rear axle cylinder. The inlet and outlet of the rod chamber element 7 of the rear axle cylinder is connected to the first inlet and outlet of the rod chamber oil variable volume element 31 of the rear axle cylinder.

[0065] Specifically, the inlet of the rear axle cylinder damping orifice element 9 is connected to the second inlet / outlet of the rodless chamber oil variable volume element 12 of the rear axle cylinder, and the outlet of the rear axle cylinder damping orifice element 9 is connected to the second inlet / outlet of the rod chamber oil variable volume element 31 of the rear axle cylinder; the inlet of the rear axle cylinder check valve element 10 is connected to the second inlet / outlet of the rodless chamber oil variable volume element 12 of the rear axle cylinder, and the outlet of the rear axle cylinder check valve element 10 is connected to the second inlet / outlet of the rod chamber oil variable volume element 31 of the rear axle cylinder; the first force-applying port of the rear axle cylinder check valve stroke limiting element 32 is connected to the force-receiving port of the rear axle cylinder check valve element 10;

[0066] The accumulator equivalent element group includes a low-pressure gas chamber element 15, a low-pressure gas chamber stroke limit element 29, a low-pressure rodless hydraulic chamber element 16, a low-pressure gas variable volume element 18, a high-pressure gas chamber element 19, a high-pressure gas chamber stroke limit element, a high-pressure rodless hydraulic chamber element 20, a high-pressure gas variable volume element 22, and an accumulator oil variable volume element 30.

[0067] The first inlet and outlet of the low-pressure gas variable volume element 18 are connected to the inlet and outlet of the low-pressure gas chamber; the force-bearing port of the low-pressure gas chamber element 15 is connected to the first force-applying port of the low-pressure gas chamber stroke limiting element 29; the second force-applying port of the low-pressure gas chamber stroke limiting element 29 is connected to the force-bearing port of the low-pressure rodless hydraulic chamber element 16; the inlet and outlet of the low-pressure rodless hydraulic chamber element 16 are connected to the first inlet and outlet of the accumulator oil variable volume element 30; the first inlet and outlet of the high-pressure gas variable volume element 22 are connected to the inlet and outlet of the high-pressure gas chamber; the force-bearing port of the high-pressure gas chamber element 19 is connected to the first force-applying port of the high-pressure gas chamber stroke limiting element; the second force-applying port of the high-pressure gas chamber stroke limiting element is connected to the force-bearing port of the high-pressure rodless hydraulic chamber element 20; the inlet and outlet of the high-pressure rodless hydraulic chamber element 20 are connected to the first inlet and outlet of the accumulator oil variable volume element 30.

[0068] One end of the first connecting pipe element 13 is connected to the inlet and outlet of the rodless chamber element 2 of the middle axle cylinder, and the other end is connected to the second inlet and outlet of the accumulator oil variable volume element 30. One end of the second connecting pipe element 14 is connected to the inlet and outlet of the rodless chamber element 8 of the rear axle cylinder, and the other end is connected to the third inlet and outlet of the accumulator oil variable volume element 30.

[0069] The displacement output port of the middle axle cylinder displacement excitation element 25 is connected to the piston rod displacement input port of the rod chamber element 1 of the middle axle cylinder, and the displacement output port of the rear axle cylinder displacement excitation element 26 is connected to the piston rod displacement input port of the rod chamber element 7 of the rear axle cylinder; the middle axle cylinder displacement excitation element 25 and the rear axle cylinder displacement excitation element 26 are respectively connected to the corresponding displacement step signal.

[0070] The middle axle cylinder stroke limiting element 27 is used to simulate the limiting of the middle axle cylinder's extension and compression strokes; the middle axle cylinder check valve stroke limiting element 28 is used to push the ball on the check valve element to simulate the opening degree of the check valve; the middle axle cylinder rod chamber oil variable volume element 34, the middle axle cylinder rodless chamber oil variable volume element 6, the rear axle cylinder rod chamber oil variable volume element 31, the rear axle cylinder rodless chamber oil variable volume element 12, and the accumulator oil variable volume element 30 are all used to store or release the pressure energy generated when the oil volume in the corresponding chamber changes; the low-pressure gas variable volume element 18 and the high-pressure gas variable volume element 22 are both used to store or release the pressure energy generated when the gas volume in the corresponding chamber changes; in actual use, the middle axle cylinder displacement excitation element 25 and the rear axle cylinder displacement excitation element 26 are connected to the corresponding displacement step signal, which is used to simulate the change of cylinder displacement.

[0071] The selection and source of each component in each simulation software are well known to those skilled in the art. The following uses Amesim2304 software as an example to further illustrate the model numbers of each component, making implementation easier for those skilled in the art. Details are as follows:

[0072] The rod chamber element 1 of the middle axle cylinder is selected from the software as a BRP17 element, that is, the rod chamber element 1 of the middle axle cylinder is a BRP17 element. Similarly, the rodless chamber element 2 of the middle axle cylinder is a BRP18 element, the damping orifice element 3 of the middle axle cylinder is a BHORF0 element, the one-way valve element 4 of the middle axle cylinder is a BAP22 element, the one-way valve stroke limit element 28 of the middle axle cylinder is a MECMAS21 element, the variable volume oil element 6 of the rodless chamber of the middle axle cylinder and the variable volume oil element 34 of the rod chamber of the middle axle cylinder are both BHC11 elements, and the stroke limit element 27 of the middle axle cylinder is a MAS010RT element.

[0073] The model of each component in the equivalent component group of the rear axle cylinder is consistent with the model of the corresponding component in the equivalent component group of the middle axle cylinder. Specifically: the rod chamber component 7 of the rear axle cylinder is a BRP17 component, the rodless chamber component 8 of the rear axle cylinder is a BRP18 component, the damping orifice component 9 of the rear axle cylinder is a BHORF0 component, the one-way valve component 10 of the rear axle cylinder is a BAP22 component, the one-way valve stroke limit component 32 of the rear axle cylinder is a MECMAS21 component, the variable volume oil component 12 of the rodless chamber of the rear axle cylinder and the variable volume oil component 31 of the rod chamber of the rear axle cylinder are both BHC11 components, and the stroke limit component 33 of the rear axle cylinder is a MAS010RT component.

[0074] In the accumulator equivalent element group: the low-pressure gas chamber element 15 is a PNPA001 element, the low-pressure gas chamber stroke limiting element 29 is a MECMAS21 element, the low-pressure rodless hydraulic chamber element 16 is a BAP12 element, the low-pressure gas variable volume element 18 is a PNCH012 element, the high-pressure gas chamber element 19 is a PNPA001 element, the high-pressure gas chamber stroke limiting element 35 is a MECMAS21 element, the high-pressure rodless hydraulic chamber element 20 is a BAP12 element, the high-pressure gas variable volume element 22 is a PNCH012 element; and the accumulator oil variable volume element 30 is a BHC11 element.

[0075] A pair of connecting pipe elements: both the first connecting pipe element 13 and the second connecting pipe element 14 are HL0002 elements;

[0076] Both the middle axle cylinder displacement excitation element 25 and the rear axle cylinder displacement excitation element 26 are XVLC01 elements.

[0077] It is important to note that the connections of each component must follow physical logic. For example, on the oil / gas flow path, the relevant ports of the component (such as liquid inlet / outlet, gas inlet / outlet, etc.) should be connected to the relevant ports of the component to be connected (such as liquid inlet / outlet, gas inlet / outlet, etc.). Similarly, on the path of a load-applying component, such as applying a load to a hydraulic cylinder, the force-bearing port of the cylinder should be connected to the relevant port of the simulated mechanical mass block component, and so on. Other unnecessary ports should be blocked. It is also important to note that the connections of each component are familiar to those skilled in the art using Amesim software. If the channel connection is incorrect, such as connecting a mechanical port to a hydraulic port, Amesim software will display a connection failure.

[0078] In this technical solution, since the displacement excitation element 25 of the middle axle cylinder and the displacement excitation element 26 of the rear axle cylinder are respectively connected to the corresponding displacement step signals, a method is provided to input the stroke corresponding to each point on the stroke change curve into the simulation model. Specifically, for each working condition, the stroke change curve can be first decomposed into the time-displacement curve of the middle axle cylinder and the time-displacement curve of the corresponding rear axle cylinder. The time-displacement curve is the displacement step signal loaded at the corresponding cylinder in the simulation model, used to simulate the stroke of the corresponding cylinder. The specific time-displacement curve can have various forms, as long as it includes the entire range of the stroke change curve. A preferred method is provided below: Figure 7 As shown, the displacement step signals corresponding to the middle axle cylinder and the rear axle cylinder are set according to five typical working conditions, with five sets of step signals showing the change of cylinder stroke over time. Figure 7The displacement step signal of the middle axle cylinder is represented by the horizontal axis, which is time (min). The time can be designed according to the actual operating conditions. The vertical axis is the stroke. The stroke is generally set to 0-maximum compression stroke-0-maximum tension stroke-0 as one cycle. This makes the simulation system more stable during operation and avoids the middle axle cylinder displacement being calculated from the maximum tension or maximum compression state at the beginning, which is prone to errors. The displacement step signal of the rear axle cylinder can be generated according to the stroke corresponding to the stroke of the middle axle cylinder (it should be noted that at any point in time under each working condition, the stroke of the middle axle cylinder and the stroke of the rear axle cylinder are one-to-one correspondences).

[0079] The beneficial effect of adopting this technical solution is that it provides a simulation model structure for a single-sided connected oil-gas suspension system for the middle and rear axles, which is especially suitable for building in Amesim software. Using this simulation model structure to simulate a single-sided connected oil-gas suspension system for the middle and rear axles yields good simulation results.

[0080] In another technical solution, the equivalent simulation model also includes a middle axle cylinder force sensor element 23 and a rear axle cylinder force sensor element 24. The equivalent element group of the middle axle cylinder also includes a rodless chamber pressure sensor element 5 of the middle axle cylinder. The equivalent element group of the rear axle cylinder also includes a rodless chamber pressure sensor element 11 of the rear axle cylinder. The equivalent element group of the accumulator also includes a high pressure sensor element 21 and a low pressure sensor element 17.

[0081] Specifically, the rodless chamber pressure sensor element 5 of the middle axle cylinder is connected to the rodless chamber oil variable volume element of the equivalent element group of the middle axle cylinder; the rodless chamber pressure sensor element 11 of the rear axle cylinder is connected to the rodless chamber oil variable volume element of the equivalent element group of the rear axle cylinder; the high pressure sensor element 21 is connected to the high pressure gas variable volume element 22; the low pressure sensor element 17 is connected to the low pressure gas variable volume element 18; the force sensor element 23 of the middle axle cylinder is connected to the rod chamber element in the equivalent element group of the middle axle cylinder; and the force sensor element 24 of the rear axle cylinder is connected to the rod chamber element in the equivalent element group of the rear axle cylinder.

[0082] In the above technical solution, the equivalent element group of the middle axle cylinder further includes a rodless chamber pressure sensor element 5, the equivalent element group of the rear axle cylinder further includes a rodless chamber pressure sensor element 11, the equivalent element group of the accumulator further includes a high-pressure sensor element 21 and a low-pressure sensor element 17, and the equivalent simulation model further includes a middle axle cylinder force sensor element 23 and a rear axle cylinder force sensor element 24; wherein, the input port of the rodless chamber pressure sensor element 5 of the middle axle cylinder is connected to the pressure output port of the rodless chamber oil variable volume element 6 of the middle axle cylinder, and the pressure of the rodless chamber of the rear axle cylinder is... The input port of sensor element 11 is connected to the pressure output port of the rodless chamber oil variable volume element 12 of the rear axle cylinder; the input port of high pressure sensor element 21 is connected to the pressure output port of high pressure gas variable volume element 22; the input port of low pressure sensor element 17 is connected to the pressure output port of low pressure gas variable volume element 18; the input port of middle axle cylinder force sensor element 23 is connected to the force output port of the rod chamber element 1 of the middle axle cylinder; and the input port of rear axle cylinder force sensor element 24 is connected to the force output port of the rod chamber element 7 of the rear axle cylinder.

[0083] Taking Amesim2304 software as an example, the selection of each component is as follows: the rodless chamber pressure sensor element 5 of the middle axle cylinder and the rodless chamber pressure sensor element 11 of the rear axle cylinder are both RT001 elements; the high pressure sensor element 21 and the low pressure sensor element 17 are both PNPS001 elements; and the force sensor element 23 of the middle axle cylinder and the force sensor element 24 of the rear axle cylinder are both MECFS0A elements.

[0084] The beneficial effect of adopting this technical solution is that by setting the rodless chamber pressure sensor element 5 of the middle axle cylinder, the rodless chamber pressure sensor element 11 of the rear axle cylinder, the high pressure sensor element 21, the low pressure sensor element 17, the force sensor element 23 of the middle axle cylinder, and the force sensor element 24 of the rear axle cylinder, the data of the above sensor elements can be output to the Adams dynamics model through the interface protocol when performing joint simulation of this equivalent simulation model with the Adams multibody dynamics model, making it more convenient to use.

[0085] In another technical solution, the typical working conditions are five types: parallel wheel jump, asymmetrical parallel wheel jump, single wheel jump, asymmetrical reverse wheel jump, and reverse wheel jump.

[0086] In the above technical solution, the present invention breaks down the complex working conditions into five typical working conditions: parallel wheel jump, asymmetrical parallel wheel jump, single wheel jump, asymmetrical reverse wheel jump, and reverse wheel jump. Specifically, parallel wheel jump refers to the equal amplitude movement of the middle and rear axles (e.g., ±100mm); asymmetrical parallel wheel jump refers to the middle and rear axles moving in the same direction but with a difference in amplitude of 2 times (e.g., middle axle ±100mm, rear axle ±50mm); single wheel jump refers to movement of only one side of the cylinder (e.g., middle axle ±150mm, rear axle 0mm); asymmetrical reverse wheel jump refers to the middle and rear axles moving in opposite directions with a difference in amplitude of 2 times (e.g., middle axle +100mm / -50mm, rear axle -50mm / +25mm); and reverse wheel jump... The five typical working conditions refer to the equal-amplitude reverse motion of the middle and rear axles (e.g., middle axle +150mm / -150mm, rear axle -150mm / +150mm). These conditions comprehensively characterize the displacement changes of the middle and rear axle cylinders. By breaking down all the complex working conditions of mining dump trucks traveling on uneven mining roads into typical working conditions, the suspension travel range under each typical working condition is obtained. Furthermore, through simulation models, the stiffness performance of the middle and rear connected suspension system under different working conditions can be accurately obtained. This provides a model basis for designing cylinder travel, suspension motion analysis, and force analysis for the suspension system. Applying the method provided by this invention can increase the success rate of suspension system design, reduce suspension system operation failures, and improve the overall vehicle driving stability.

[0087] In another technical solution, the specific method for obtaining the stroke of the middle axle cylinder and the rear axle cylinder in the single-sided connected hydraulic suspension system under five working conditions—parallel wheel jump, asymmetrical parallel wheel jump, single wheel jump, asymmetrical reverse wheel jump, and reverse wheel jump—is as follows:

[0088] A1. Let S be the compression stroke of the middle axle cylinder / rear axle cylinder under no-load conditions. 空上 The tension stroke under no-load conditions is denoted as S. 空下 The compression stroke under full load is denoted as S. 满上 The tensile stroke under full load is denoted as S. 满下 Let L be the static deflection of the middle axle cylinder / rear axle cylinder from no-load state to full-load state, then S 空上 =S 满上 +L, S 空下 =S 满下 -L;

[0089] A2. Under full load, the stroke calculation methods for the middle axle cylinder and the rear axle cylinder under five different working conditions are as follows:

[0090] Under parallel wheel runout conditions: S-axis of the middle axle cylinder and the rear axle cylinder 满上 The values ​​are all min(a, c / 2), S 满下The values ​​are all -[min(b, d / 2)];

[0091] Under asymmetrical parallel wheel jump conditions: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, c / 2), S 满下 The value is -[min(b, d / 2)], and the S value of the other cylinder is... 满上 The value is 0.5*min(a, c / 2), S 满下 The value is -[0.5*min(b, d / 2)];

[0092] Under single-wheel jump condition: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, c) and S. 满下 The value is -[min(b, d)], and the S of the other cylinder is... 满上 The values ​​are 0 and S. 满下 The value is 0;

[0093] Under asymmetrical reverse wheel runout conditions: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, b) and S. 满下 The value is -[min(a, b)], and the S of the other cylinder is... 满上 The value is -[0.5*min(a, b)], S 满下 The value is 0.5*min(a, b);

[0094] Under reverse wheel runout conditions: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, b) and S. 满下 The value is -[min(a, b)], and the S of the other cylinder is... 满上 The value is -[min(a, b)], S 满下 The value is min(a, b);

[0095] Where a is the length of the rodless chamber of the cylinder under full load, b is the length of the rod chamber of the cylinder under full load, c is the total gas volume of the high-pressure chamber and the low-pressure chamber under full load / the area difference between the rodless chamber and the rod chamber of the cylinder, and d is the total oil chamber volume of the high-pressure chamber and the low-pressure chamber under full load / the area difference between the rodless chamber and the rod chamber of the cylinder.

[0096] In the above technical solution, the structures of the middle axle cylinder and the rear axle cylinder are completely identical. Here, 'a' represents the length of the rodless chamber of the cylinder. Since the calculation is based on the cylinder stroke under full vehicle load, 'a' is the length of the rodless chamber under full vehicle load. 'b' represents the length of the rod chamber under full vehicle load. 'c' represents the difference between the total gas volume of the high-pressure chamber and the low-pressure chamber under full vehicle load and the area difference between the rodless and rod chambers of the cylinder. The total gas volume of the high-pressure chamber and the low-pressure chamber refers to the sum of the volumes in the high-pressure chamber and the low-pressure chamber. 'd' represents the length of the cylinder under full vehicle load. Below, the total volume of the oil chambers in the high-pressure and low-pressure air chambers is divided by the area difference between the rodless and rod-side chambers of the cylinder. The total volume of the oil chambers in the high-pressure and low-pressure air chambers refers to the total volume of oil in the hydraulic chamber of the accumulator. It should be noted that in the above definitions of parameters a, b, c, and d, since the structures of the middle axle cylinder and the rear axle cylinder are exactly the same, the cylinder can be calculated based on either the middle axle cylinder or the rear axle cylinder. In addition, when the cylinder size type is determined, the static deflection and the area difference between the rodless and rod-side chambers of the cylinder are constant values, which is conventional knowledge in this field.

[0097] Since the stroke variation curves under each working condition are linear, the following example, using the parallel wheel jump condition, with the middle axle cylinder as the abscissa and the rear axle cylinder as the ordinate, illustrates how to obtain the stroke variation curves of the middle and rear axle cylinders under this condition: If, under the parallel wheel jump condition, the maximum value of the rodless chamber length 'a' of the middle axle cylinder is 120mm, the maximum value of the rod chamber length 'b' of the middle axle cylinder is 100mm, and the maximum total gas volume of the high-pressure and low-pressure chambers is 600mm... 3 The maximum total volume of oil in the accumulator's hydraulic chamber is 500 mm. 3 The area difference between the rodless chamber and the rod chamber of the hydraulic cylinder is 4mm. 2 ,but:

[0098] Compression stroke: Compression stroke values ​​S of the middle axle cylinder and the rear axle cylinder 满上 The maximum value is min(120, (600 / 4) / 2) (i.e., min(120, 75)), so the maximum compression stroke is 75, and the coordinate point of the maximum compression stroke is (75, 75). The minimum compression stroke is no compression, so both are 0, and the coordinate point of the minimum compression stroke is (0, 0). Therefore, the compression stroke curve under this condition is the curve between the coordinate points (0, 0) and (75, 75). Connecting these two points will give the curve. Similarly, the extension stroke value S of the middle axle cylinder and the rear axle cylinder is also given. 满下The maximum value is -[min(100, (500 / 4) / 2)] (i.e. -[min(100, 62.5)]), so the maximum tensile stroke is -62.5, and the coordinate point of the maximum tensile stroke is (-62.5, -62.5). The minimum coordinate point is (0,0) (minimum tensile stroke means no tensile stroke, so both are 0). Therefore, the tensile stroke curve under this working condition is the coordinate point (0,0) and the coordinate point (-62.5, -62.5). The line connecting the two points is sufficient.

[0099] Furthermore, under each operating condition, the stroke of the same cylinder is used as the abscissa and the stroke of the other cylinder as the ordinate. After the simulation is completed, the cylinder force curve generated by the cylinder with the larger stroke range is the required cylinder force distribution curve. It is preferable to use the cylinder with the larger stroke range as the abscissa, which is more in line with operating habits. For example, if the stroke of the middle axle cylinder is used as the abscissa and the stroke of the rear axle cylinder is used as the ordinate, then under the parallel wheel jump condition: the S-axis of the middle axle cylinder and the rear axle cylinder... 满上 The values ​​are all min(a, c / 2), S 满下 The values ​​are all -[min(b, d / 2)]; Under the asymmetric parallel wheel runout condition: S of the middle axle cylinder 满上 The values ​​are min(a, c / 2), S 满下 The value is -[min(b, d / 2)], and the S value of the rear axle cylinder is... 满上 The value is 0.5*min(a, c / 2), S 满下 The value is -[0.5*min(b, d / 2)]; Under the single-wheel jump condition: S of the middle axle cylinder 满上 The values ​​are min(a, c) and S. 满下 The value is -[min(b, d)], and the S value of the rear axle cylinder is... 满上 The values ​​are 0 and S. 满下 The value is 0; under the asymmetric reverse wheel jump condition: the S value of the middle axle cylinder 满上 The values ​​are min(a, b) and S. 满下 The value is -min(a, b), and the S value of the rear axle cylinder is... 满上 The value is -[0.5*min(a, b)], S 满下 The value is 0.5*min(a, b); Under the reverse wheel runout condition: S of the middle axle cylinder 满上 The values ​​are min(a, b) and S. 满下 The value is -[min(a, b)], and the S value of the rear axle cylinder is... 满上 The value is -[min(a, b)], S 满下 The value is min(a, b). In this case, the value range of the middle axle cylinder is larger than that of the rear axle cylinder. Therefore, after the simulation is completed, you can check the cylinder force curve generated at the middle axle cylinder.

[0100] Since the structure and arrangement of the middle axle cylinder and the rear axle cylinder are exactly the same, the cylinder force distribution curve calculated by taking the stroke of the rear axle cylinder or the middle axle cylinder as the horizontal axis can be the same as the cylinder force distribution curve of the other cylinder.

[0101] In this technical solution, the strokes of the middle axle cylinder and the rear axle cylinder under five different working conditions are first obtained. The stroke of the cylinder with the larger stroke range is used as the horizontal axis, and the stroke of the other cylinder is used as the vertical axis to plot the stroke variation distribution curve. This curve is then used as the input source and input into the subsequent equivalent simulation model for cylinder force calculation. This is equivalent to loading the strokes of the middle axle cylinder and the rear axle cylinder under each working condition into the equivalent simulation model. Each set of corresponding middle axle cylinder strokes and corresponding rear axle strokes represents the cylinder state of the vehicle under the corresponding working condition. Therefore, by applying the varying strokes of the middle axle cylinder and the rear axle cylinder under each working condition, the cylinder force variation distribution curve under that working condition can be obtained.

[0102] In another technical solution, the parameter settings of both the rod-side chamber element and the rodless chamber element include piston diameter, piston rod diameter, and chamber length; the parameter settings of both the rod-side chamber variable volume fluid element and the rodless chamber variable volume fluid element include initial pressure and dead zone volume; the parameter settings of the damping orifice element include damping orifice diameter; the parameter settings of the one-way valve element include base diameter and steel ball diameter; the parameter settings of the one-way valve stroke limiting element include the maximum and minimum displacement limits of the steel ball; and the parameter settings of the cylinder stroke limiting element include the upper displacement limit (rodless chamber length) and lower displacement limit (rod-side chamber length). In this technical solution, it should be noted that in actual use, the piston rod diameter of the rodless chamber element of the middle axle cylinder and the rodless chamber element of the rear axle cylinder is set to 0.

[0103] In another technical solution, the parameter settings of the low-pressure gas chamber element and the high-pressure gas chamber element both include piston diameter, piston rod diameter, and gas chamber length; the parameter settings of the low-pressure gas variable volume element, the high-pressure gas variable volume element, and the accumulator oil variable volume element all include initial pressure and dead zone volume; the parameter settings of the low-pressure gas chamber stroke limiting element and the high-pressure gas chamber stroke limiting element include gas compression displacement limit and gas tension displacement limit; the parameter settings of the low-pressure rodless hydraulic chamber element include piston diameter, piston rod diameter, and low-pressure hydraulic chamber length; the parameter settings of the high-pressure rodless hydraulic chamber element include piston diameter, piston rod diameter, and high-pressure hydraulic chamber length. In this technical solution, it should be noted that in actual use, the piston rod diameter of the low-pressure gas chamber element and the high-pressure gas chamber element is set to 0, and the piston rod diameter of the low-pressure rodless hydraulic chamber element and the high-pressure rodless hydraulic chamber element is also set to 0.

[0104] In another technical solution, the parameter settings of the connecting pipeline components include the inner diameter of the pipeline, the length of the pipeline, the pressure of the pipeline, and the wall thickness of the pipeline;

[0105] In this technical solution, when using it, the equivalent simulation model is run according to the conventional simulation setup and operation steps, for example, the following steps:

[0106] S1, Amesim Modeling: In SKETCH mode, drag each component into the drawing area and connect them;

[0107] S2, Amesim Component Type Settings: In SUBMODEL mode, select the sub-model corresponding to each component;

[0108] S3, Amesim Component Parameter Settings: In PARAMETER mode, set the parameters of each component according to the parameters specified above;

[0109] S4. Amesim Simulation: In Simulation mode, set Simulation mode to Dynamic, Simulation settings start time to 0, end time to the end time of the stroke corresponding to each working condition, and output time interval to 0.1s. Start simulation.

[0110] S5, Amesim View Results: In Simulation mode, after the simulation ends, clicking on any component will display the component parameter values ​​at the end of the simulation in the status bar. Dragging the component to the plotting area will display the curve of the component parameter changing over time.

[0111] <Example>

[0112] 1. Model building and simulation calculation

[0113] Based on the parameters of relevant components of the single-sided connected hydropneumatic suspension system of the middle and rear axles to be designed, and following the aforementioned stroke calculation method, the compression and extension strokes of the middle axle cylinder and the rear axle cylinder under five typical working conditions—parallel wheel jump, asymmetrical parallel wheel jump, single wheel jump, asymmetrical reverse wheel jump, and reverse wheel jump—are calculated. With the stroke of the middle axle cylinder as the abscissa (extension stroke is negative, compression stroke is positive) and the stroke of the rear axle cylinder as the ordinate (extension stroke is negative, compression stroke is positive), the stroke variation curves for each working condition are obtained (e.g., ...). Figure 4 (as shown);

[0114] An equivalent simulation model of the single-sided connected oil-gas suspension system of the middle and rear axles was constructed according to the method of the present invention (e.g., Figure 3 As shown), the stroke variation curves of these five working conditions are processed into displacement step signals of the middle axle cylinder and the rear axle cylinder respectively (i.e., similar to...). Figure 7 The stroke-time curves are obtained by loading each stroke-time curve onto the corresponding hydraulic cylinder, running the equivalent simulation model, and finally obtaining the hydraulic force distribution curve of the middle axle cylinder (e.g., ...). Figure 5 As shown in the figure, since the structure and arrangement of the middle axle cylinder and the rear axle cylinder are exactly the same, the cylinder force distribution curves of the two are consistent.

[0115] 2. Verification

[0116] The verification of the simulation analysis method for the single-sided connected hydropneumatic suspension system of the middle and rear axles in this embodiment was conducted under the test condition of parallel wheel hop. The stroke of the middle and rear axle cylinders and the pressure data of the rodless chamber of the cylinders were tested during the loading and unloading of counterweights. The tested pressure data was multiplied by the area difference between the rodless and rod chambers to obtain the tested cylinder force. A comparison and analysis of the cylinder force and stroke change curves from the simulation and the test showed an error of only 1%, indicating high accuracy in calculating the suspension stiffness using the simulation analysis model. Figure 6 As shown.

[0117] 3. Model Usage

[0118] Based on the cylinder stroke of the mining dump truck under different working conditions (input: stroke corresponding to different working conditions), the range of cylinder force variation of the suspension is obtained. It is important to note that the points on and between the obtained curves are the points where the cylinder force of the suspension is measured; that is, the range of cylinder force values ​​for the suspension is formed on and between each curve. The method of this invention obtains the cylinder force variation distribution curve, which can provide accurate basic data for suspension design, improving the efficiency and success rate of suspension design.

[0119] The number of devices and processing scale described herein are for the purpose of simplifying the description of this invention. Applications, modifications, and variations of the simulation analysis method for the rear axle single-sided connected hydropneumatic suspension system in this invention will be readily apparent to those skilled in the art.

[0120] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A simulation analysis method for a single-sided connected oil-gas suspension system for the middle and rear axles, characterized in that, Includes the following steps: S1. Obtain the corresponding strokes of the middle axle cylinder and the rear axle cylinder in the single-sided connected oil-pneumatic suspension system of the middle and rear axles under various working conditions. For each working condition, take the stroke of one cylinder as the horizontal axis and the stroke of the other cylinder as the vertical axis to obtain the stroke change curve under each working condition. S2. Based on the structure of the single-sided connected oil-pneumatic suspension system of the middle and rear axles, an equivalent simulation model of the single-sided connected oil-pneumatic suspension of the middle and rear axles is built. The stroke change curve obtained in S1 is input into the built equivalent simulation model to obtain the cylinder force change distribution curve of the middle axle cylinder and / or the rear axle cylinder.

2. The simulation analysis method for a single-sided connected oil-gas suspension system of the middle and rear axles as described in claim 1, characterized in that, The single-sided connected hydraulic suspension system for the middle and rear axles includes a middle axle cylinder, a rear axle cylinder, an accumulator, and a pair of connecting pipes. The piston rods of both the middle axle cylinder and the rear axle cylinder are equipped with one-way valves and damping holes. The accumulator includes a cavity, in which a pair of sliding sealing plugs are spaced apart to divide the cavity into a low-pressure air chamber, a hydraulic chamber, and a high-pressure air chamber. The hydraulic chamber is connected to the rodless chambers of the middle axle cylinder and the rear axle cylinder respectively through a pair of connecting pipes.

3. The simulation analysis method for a single-sided connected oil-gas suspension system of the middle and rear axles as described in claim 2, characterized in that, The equivalent simulation model built in step S2 includes the equivalent element group of the middle axle cylinder, the equivalent element group of the rear axle cylinder, the equivalent element group of the accumulator, a pair of connecting pipeline elements, the displacement excitation element of the middle axle cylinder, and the displacement excitation element of the rear axle cylinder. The equivalent element group of the middle bridge cylinder includes a rod-side chamber element, a rodless chamber element, a damping orifice element, a check valve element, a check valve stroke limiting element, a rodless chamber variable volume oil element, a rod-side variable volume oil element, and a cylinder stroke limiting element. The rodless chamber element is connected to the rodless chamber variable volume oil element, the cylinder stroke limiting element, and the rod-side chamber element. The rod-side chamber element is connected to the rod-side variable volume oil element and the middle bridge cylinder displacement excitation element. The damping orifice element and the check valve element are both connected between the rod-side variable volume oil element and the rodless chamber variable volume oil element. The check valve element is connected to the check valve stroke limiting element. The structure of the equivalent element group of the rear axle cylinder is the same as that of the equivalent element group of the middle axle cylinder; The accumulator equivalent element group includes a low-pressure gas chamber element, a low-pressure gas chamber stroke limiting element, a low-pressure rodless hydraulic chamber element, a low-pressure gas variable volume element, a high-pressure gas chamber element, a high-pressure gas chamber stroke limiting element, a high-pressure rodless hydraulic chamber element, a high-pressure gas variable volume element, and an accumulator oil variable volume element. The low-pressure gas chamber element is connected to the low-pressure gas variable volume element and the low-pressure gas chamber stroke limiting element, and the low-pressure gas chamber stroke limiting element is connected to the low-pressure rodless hydraulic chamber element. The high-pressure gas chamber element is connected to the high-pressure gas variable volume element and the high-pressure gas chamber stroke limiting element, and the high-pressure gas chamber stroke limiting element is connected to the high-pressure rodless hydraulic chamber element. The low-pressure rodless hydraulic chamber element and the high-pressure rodless hydraulic chamber element are both connected to the accumulator oil variable volume element. Among them, a pair of connecting pipe elements correspond to the rodless cavity elements in the equivalent element group of the middle axle cylinder and the equivalent element group of the rear axle cylinder, respectively. One end of the connecting pipe element is connected to the corresponding rodless cavity element, and the other end is connected to the variable volume element of the accumulator oil. The displacement excitation element of the middle axle cylinder is connected to the rod cavity element in the equivalent element group of the middle axle cylinder, and the displacement excitation element of the rear axle cylinder is connected to the rod cavity element in the equivalent element group of the rear axle cylinder.

4. The simulation analysis method for a single-sided connected oil-gas suspension system of the middle and rear axles as described in claim 3, characterized in that, The equivalent simulation model also includes a force sensor element for the middle axle cylinder and a force sensor element for the rear axle cylinder. The equivalent element group for the middle axle cylinder also includes a pressure sensor element for the rodless chamber of the middle axle cylinder. The equivalent element group for the rear axle cylinder also includes a pressure sensor element for the rodless chamber of the rear axle cylinder. The equivalent element group for the accumulator also includes a high-pressure sensor element and a low-pressure sensor element. Specifically, the rodless chamber pressure sensor element of the middle axle cylinder is connected to the rodless chamber oil variable volume element of the equivalent element group of the middle axle cylinder; the rodless chamber pressure sensor element of the rear axle cylinder is connected to the rodless chamber oil variable volume element of the equivalent element group of the rear axle cylinder; the high-pressure pressure sensor element is connected to the high-pressure gas variable volume element; the low-pressure pressure sensor element is connected to the low-pressure gas variable volume element; the force sensor element of the middle axle cylinder is connected to the rod chamber element in the equivalent element group of the middle axle cylinder; and the force sensor element of the rear axle cylinder is connected to the rod chamber element in the equivalent element group of the rear axle cylinder.

5. The simulation analysis method for a single-sided connected oil-gas suspension system of the middle and rear axles as described in claim 1, characterized in that, The various working conditions include five types: parallel wheel jump, asymmetrical parallel wheel jump, single wheel jump, asymmetrical reverse wheel jump, and reverse wheel jump.

6. The simulation analysis method for a single-sided connected oil-gas suspension system of the middle and rear axles as described in claim 5, characterized in that, The specific method for obtaining the stroke of the middle axle cylinder and rear axle cylinder in the single-sided connected hydraulic suspension system of the middle and rear axles under five working conditions—parallel wheel hop, asymmetrical parallel wheel hop, single wheel hop, asymmetrical reverse wheel hop, and reverse wheel hop—is as follows: A1. Let S be the compression stroke of the middle axle cylinder / rear axle cylinder under no-load conditions. 空上 The tension stroke under no-load conditions is denoted as S. 空下 The compression stroke under full load is denoted as S. 满上 The tensile stroke under full load is denoted as S. 满下 Let L be the static deflection of the middle axle cylinder / rear axle cylinder from no-load state to full-load state, then S 空上 =S 满上 +L, S 空下 =S 满下 -L; A2. Under full load, the stroke calculation methods for the middle axle cylinder and the rear axle cylinder under five different working conditions are as follows: Under parallel wheel runout conditions: S-axis of the middle axle cylinder and the rear axle cylinder 满上 The values ​​are all min(a, c / 2), S 满下 The values ​​are all -[min(b, d / 2)]; Under asymmetrical parallel wheel runout conditions: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, c / 2), S 满下 The value is -min(b, d / 2), and the S of the other cylinder is... 满上 The value is 0.5*min(a, c / 2), S 满下 The value is -[0.5*min(b, d / 2)]; Under single-wheel jump condition: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, c) and S. 满下 The value is -[min(b, d)], and the S of the other cylinder is... 满上 The values ​​are 0 and S. 满下 The value is 0; Under asymmetrical reverse wheel runout conditions: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, b) and S. 满下 The value is -[min(a, b)], and the S of the other cylinder is... 满上 The value is -[0.5*min(a, b)], S 满下 The value is 0.5*min(a, b); Under reverse wheel runout conditions: In the middle axle cylinder and the rear axle cylinder, the S-axis of one of the cylinders... 满上 The values ​​are min(a, b) and S. 满下 The value is -[min(a, b)], and the S of the other cylinder is... 满上 The value is -[min(a, b)], S 满下 The value is min(a, b); Where a is the length of the rodless chamber of the cylinder under full load, b is the length of the rod chamber of the cylinder under full load, c is the total gas volume of the high-pressure chamber and the low-pressure chamber under full load / the area difference between the rodless chamber and the rod chamber of the cylinder, and d is the total oil chamber volume of the high-pressure chamber and the low-pressure chamber under full load / the area difference between the rodless chamber and the rod chamber of the cylinder.

7. The simulation analysis method for a single-sided connected oil-gas suspension system of the middle and rear axles as described in claim 3, characterized in that, The parameter settings for both the rod-type chamber element and the rodless chamber element include piston diameter, piston rod diameter, and chamber length. The parameter settings for both the rod-type chamber variable volume fluid element and the rodless chamber variable volume fluid element include initial pressure and dead zone volume. The parameter settings for the damping orifice element include damping orifice diameter. The parameter settings for the one-way valve element include base diameter and steel ball diameter. The parameter settings for the one-way valve stroke limiting element include the maximum and minimum displacement limits of the steel ball. The parameter settings for the cylinder stroke limiting element include the upper and lower displacement limits of the cylinder.

8. The simulation analysis method for a single-sided connected oil-gas suspension system of the middle and rear axles as described in claim 3, characterized in that, The parameter settings for the low-pressure gas chamber element and the high-pressure gas chamber element all include piston diameter, piston rod diameter, and gas chamber length; the parameter settings for the low-pressure gas variable volume element, the high-pressure gas variable volume element, and the accumulator oil variable volume element all include initial pressure and dead zone volume; the parameter settings for the low-pressure gas chamber stroke limiting element and the high-pressure gas chamber stroke limiting element include gas compression displacement limit and gas tension displacement limit; the parameter settings for the low-pressure rodless hydraulic chamber element include piston diameter, piston rod diameter, and low-pressure hydraulic chamber length; the parameter settings for the high-pressure rodless hydraulic chamber element include piston diameter, piston rod diameter, and high-pressure hydraulic chamber length.

9. The simulation analysis method for a single-sided connected hydropneumatic suspension system of the middle and rear axles as described in claim 8, characterized in that, The parameter settings for the connecting pipeline components include the inner diameter of the pipeline, the length of the pipeline, the pressure of the pipeline, and the wall thickness of the pipeline.

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