Accelerated life test method for air compressor suction valve of automobile suspension system

Abstract

The application belongs to the technical field of compressors, and discloses an accelerated life test method for an air suction valve plate of an air compressor of an automobile suspension system, which comprises the following steps: determining the expected life and failure mode of the air suction valve plate under normal use conditions; determining an accelerated stress level and the number N of valve plate samples; recording the failure time t' of the N air suction valve plates during the test; determining the life characteristic quantity η of the air suction valve plate; calculating the expected life t of the N air suction valve plates under normal use conditions; judging the error ε between the expected life t and the life characteristic quantity η, correcting the coefficient parameter in the life cycle stress model until the final determined acceleration factor AF is obtained, repeating the accelerated life test of one air suction valve plate to obtain the failure time t'; and converting the failure time t' of the accelerated test into the expected life t of the air suction valve plate of the air compressor of the automobile suspension system by using the final determined acceleration factor AF. The application is applied to life prediction of the air suction valve, has small error and is economical and efficient.

Description

Technical Field

[0001] This invention belongs to the field of compressor technology, and specifically relates to an accelerated life test method for the intake valve plate of an air compressor in an automotive suspension system. Background Technology

[0002] The most direct benefit of air suspension is adjustable vehicle height. Vehicles equipped with air suspension can lower their ground clearance at high speeds, reducing wind resistance and thus lowering energy consumption. Compared to the metal components of traditional suspension systems, air suspension effectively reduces weight, thereby increasing the driving range of new energy vehicles.

[0003] The air compressor is the core of the air supply unit. High-pressure compressed air is generated by a single-stage reciprocating piston compressor. Piston compressors with an integrated connecting rod and piston design meet the requirements of high integration and lightweight design. However, the integrated connecting rod and piston design causes the piston to exhibit lateral oscillation motion in the vertical axial direction during the intake and compression processes, in addition to the axial movement of a traditional piston compressor. The intake valve is a core component of the piston compressor, and the axial oscillation motion of the piston presents new challenges to the design of the intake valve.

[0004] During compressor operation, the valve plates are constantly opening and closing under the influence of fluid forces, continuously enduring bending and impact stresses. Excessive stress concentration or excessively rapid impact response time will shorten the valve plate life. The valve plate life directly affects the compressor's reliability, system maintenance costs, and maintenance cycles. Therefore, predicting and studying the operating life of the compressor's suction valve is crucial.

[0005] However, current research on air compressors for automotive suspension systems is relatively scarce, and research on the lifespan of valve plates in piston compressors with lightweight integrated swing-link piston designs is even rarer. Using conventional valve plate lifespan research methods is highly uneconomical and too costly. The characteristics of the impact of swing-link compression motion on the lifespan of the intake valve at the piston top still need to be determined. Summary of the Invention

[0006] The purpose of this invention is to provide an accelerated life test method for the intake valve plate of an air compressor in an automotive suspension system, to accurately predict the normal operating life of the intake valve of a rocking piston air compressor, and to ensure the operational stability of the automotive suspension system, thereby filling a research gap in this area.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] Accelerated life test methods for intake valve plates of air compressors in automotive suspension systems include:

[0009] S1. Determine the expected lifespan and failure modes of the intake valve plate under normal operating conditions;

[0010] S2. Conduct experiments on the intake valve plate to determine the pressure difference and temperature on both sides of the intake valve plate during intake and compression; determine the lateral stress on the intake valve plate during the piston rod swinging motion.

[0011] S3. Select the life cycle stress model and use the pressure difference, temperature and lateral stress determined in step S2 to calculate the acceleration factor of the intake valve plate.

[0012] S4. Determine the accelerated stress level and the number of valve sample N for the accelerated life test of the intake valve plate of the air compressor in the automotive suspension system.

[0013] S5. Based on the accelerated stress level and the number of valve plate samples N, conduct accelerated stress tests on the intake valve plates and record the failure time t′ of N intake valve plates during the test.

[0014] S6. Use Weibull lifetime distribution analysis to perform statistical analysis on the failure times t′ of N tests to obtain the lifetime probability distribution of the intake valve plate failure; determine the lifetime characteristic quantity η of the intake valve plate based on the lifetime probability distribution of the intake valve plate failure.

[0015] S7. Based on the failure time t′ of the N intake valves in step S5 and the acceleration factor obtained in step S3, calculate the expected lifespan t of the N intake valves under normal operating conditions; determine the error ε between the expected lifespan t of the N intake valves under normal operating conditions and the lifespan characteristic quantity η of the intake valves determined in step S6, and determine whether all errors ε are less than the preset value; if there is an error ε greater than the preset value, correct the coefficient parameters in the life cycle stress model.

[0016] S8. Based on the modified life cycle stress model, repeat steps S3-S7 until the error ε between the expected life t of N intake valves under normal use conditions and the life characteristic quantity η of the intake valve determined in step S6 is within the preset value range. Record the acceleration factor AF at this time as the final determined acceleration factor.

[0017] S9. Based on the final determined acceleration factor AF, repeat steps S4-S5 to conduct an accelerated life test on an intake valve plate and obtain the failure time t′; use the final determined acceleration factor AF to convert the failure time t′ of the accelerated test into the expected life t of the intake valve plate of the automotive suspension system air compressor:

[0018]

[0019] A further improvement of the present invention is that: in step S1, the expected lifespan and failure mode of the intake valve plate under normal operating conditions are determined based on the collected historical data.

[0020] A further improvement of the present invention is that the lateral stress F on the intake valve plate in step S2 is... l Determined by the piston's oscillating acceleration 'a':

[0021] F l =f() (1)

[0022] The piston's oscillating acceleration 'a' is related to the piston rod length 'l', the crankshaft's angular velocity 'ω', and the crankshaft radius 'r'.

[0023] a=f( ,r,ω) (2)

[0024] The tilt angle of the intake valve plate during the piston intake and compression process is θ; the temperature and pressure of the gas environment in which the intake valve plate is located are constantly changing; the compressor speed is N1; then the cycle length T of the intake and compression process is:

[0025] The angular velocity of the crankshaft is ω:

[0026]

[0027] The crankshaft rotates at an angle α:

[0028]

[0029] The deflection angle is θ:

[0030]

[0031]

[0032] The actual state equation for the air compression process is:

[0033]

[0034] Where: P is the gas pressure; V is the gas volume; n is the number of gas moles; R is the gas constant; T is the Kelvin temperature of the gas; a is the intermolecular attraction parameter; b is the molecular volume parameter;

[0035] The gas volume is the volume of the compression cylinder:

[0036]

[0037] In the formula: h and d are the height and width of the compressor cylinder, respectively;

[0038] The method for calculating the pressure difference across the intake valve plate is as follows:

[0039]

[0040] In the formula: P is the compressed gas pressure, and P0 is the atmospheric pressure.

[0041] A further improvement of this invention is that the method for calculating the acceleration factor in step S3 is as follows:

[0042] by Using time intervals as units, solve equations (12)-(15) simultaneously to calculate the tilt angles of the piston surface where the intake valve plate is located for each time interval, namely θ1, θ2, ..., θ n′ The gas pressure differences across the valve plate are ΔP1, ΔP2, ΔP3, ..., ΔP n′ Temperatures are T1, T2, ..., T n′ The acceleration factor for each time unit is determined according to formula (5): AF1, AF2, ..., AF n′ Then, by integrating and averaging the acceleration factor over time using formula (16), the acceleration factor of the intake valve plate determined in step S3 is obtained:

[0043]

[0044] Formula (5) is specifically as follows:

[0045]

[0046] In the formula: CθΔP′ is the gas pressure difference during the accelerated test; ΔP is the pressure difference during actual operation; T′ is the gas temperature during the accelerated test; and T is the gas temperature during actual operation.

[0047] A further improvement of the present invention is that: in step S3, the Arrhenius life cycle stress model is selected.

[0048] A further improvement of this invention is that the number of valve plate samples N is calculated based on the Weibull lifetime distribution model, and the characteristic lifetime calculation method at a confidence level of 60% is as follows:

[0049]

[0050] In the formula, x represents the failure degree of the intake valve plate at x%; t″ represents the time required for the intake valve plate to achieve the failure degree of x%; s and N represent the number of failures and the total number of failures of the intake valve plate at the i-th failure time, respectively; h represents the target characteristic lifetime of the intake valve plate; the calculation method for the sample size N is as follows:

[0051]

[0052] A further improvement of this invention is that, in step S6, the lifespan characteristic quantity η of the intake valve plate is:

[0053]

[0054] In the formula, A is a constant related to the failure mode and acceleration type; Ea is the activation energy determined by the material properties of the intake valve plate; k is the Boltzmann constant; θ is the tilt angle of the piston rod; C is the correction coefficient; ΔP represents the stress generated by the pressure difference between the inside and outside of the gas in the direction perpendicular to the surface of the intake valve plate.

[0055] A further improvement of the present invention is that the error ε in step S7 is generally 10% to 20%.

[0056] A further improvement of the present invention is that the recommended value for the error ε in step S7 is 10%.

[0057] A further improvement of the present invention is that the accelerated stress level of the intake valve plate accelerated life test in step S4 is greater than the stress level under normal use conditions, but less than the stress level at which the unexpected failure mode begins to occur.

[0058] Compared with the prior art, the present invention has the following beneficial effects:

[0059] Existing technologies lack a clear method for determining the service life of compressor valve plates in integrated crankshaft and screw designs for automotive suspension systems. Furthermore, these integrated valve plates are simultaneously subjected to forces perpendicular to their surface and lateral forces caused by the piston rod's rocking motion during compression and intake cycles. Therefore, the service life of valve plates in integrated rocking piston air compressors differs significantly from that of conventional compressor valve plates. This invention provides an accelerated life testing method for the intake valve plates of automotive suspension system air compressors, addressing the operating state and stress conditions of the compressor's intake valve. This method accurately predicts the normal operating life of rocking piston air compressor intake valves, ensuring the operational stability of automotive suspension systems and filling this research gap.

[0060] Furthermore, compared to destructive lifetime experiments, this invention can calculate the accurate sample size using a distribution model, shortening the experimental time and offering the advantages of cost-effectiveness. Attached Figure Description

[0061] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0062] Figure 1This is a schematic diagram of the structure of an air compressor for an automotive suspension system according to the present invention;

[0063] Figure 2 This is a schematic diagram of the intake valve plate of an air compressor for an automotive suspension system according to the present invention;

[0064] Figure 3 This is a schematic diagram of the valve plate states during the intake and compression processes of an air compressor in an automotive suspension system according to the present invention; wherein... Figure 3 (a) is a schematic diagram of the inhalation process; Figure 3 (b) is a schematic diagram of the compression process. Detailed Implementation

[0065] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0066] The following detailed description is exemplary and intended to provide further detailed explanation of the invention. Unless otherwise specified, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention.

[0067] Please see Figures 1 to 3 As shown, the present invention provides an accelerated life test method for the intake valve plate of an air compressor in an automotive suspension system, which accurately predicts the normal operating life of the intake valve plate of a rocking piston air compressor, thereby ensuring the operational stability of the automotive suspension system.

[0068] The air compressor for the automotive suspension system involved in this invention is a swing-type piston air compressor, comprising: a compressor cylinder 1; an intake valve 2; a connecting rod piston 3; and piston rings 4.

[0069] To achieve lightweight design, reduce radial dimensions, and address lubrication issues, the connecting rod and piston are integrated into a single unit, forming connecting rod-piston 3. This integrated design results in the piston reciprocating in a swinging motion within the compressor cylinder 1 during intake and compression. During operation, there is a certain angle θ between the piston and the wall of compressor cylinder 1, and the piston experiences a certain swinging acceleration. The intake valve 21 is located at the top of the piston and is an automatically differential pressure driven reed valve without a lift limiter. The swing angle θ of the piston's swinging motion is determined by the piston rod length l and the crankshaft radius r. The intake valve is subjected to pressure from the internal and external gas pressure difference perpendicular to its surface and lateral force from the swinging acceleration. The lateral stress F on the intake valve... l It is determined by the piston's oscillating acceleration 'a', that is:

[0070] F l=f() (1)

[0071] The piston's oscillating acceleration 'a' is related to the piston rod length 'l', the crankshaft's angular velocity 'ω', and the crankshaft radius 'r', that is:

[0072] a=f( ,r,ω) (2)

[0073] The stress fatigue at the connection between the intake valve plate and the intake valve base is divided into vertical deformation fatigue perpendicular to the valve plate surface and tensile-compressive deformation fatigue along the direction of the intake valve plate surface. During intake, the intake valve plate opens, and the stress generated by the tilting motion of the piston surface acts on the intake valve plate connection, causing compressive deformation at the connection. During compression, the intake valve plate closes, and the stress generated by the tilting motion of the piston surface acts on the intake valve plate connection, causing tensile deformation at the connection. The vertical deformation fatigue perpendicular to the intake valve plate surface and the tensile-compressive deformation fatigue along the valve plate surface alternate in each intake and compression process. Furthermore, the force generated by the acceleration of the rocking motion interferes with the lift of the intake valve plate, thus affecting the vertical deformation fatigue strength of the intake valve plate surface during the opening and closing processes.

[0074] In one specific embodiment, the present invention provides an accelerated life test method for the intake valve plate of an air compressor in an automotive suspension system, comprising the following specific steps:

[0075] S1. By collecting historical data and referring to the experience of similar products, understand the stress level and valve plate fatigue failure under normal operating conditions, and determine the expected life and failure mode of the intake valve plate under normal operating conditions (the expected life is to compare the expected life with the actual life after accelerated life testing to determine whether the actual life meets the expected requirements; the failure mode is the standard for judging valve plate failure in accelerated testing; the specific confirmation steps only need to provide clear expected life data and the definition of valve plate failure).

[0076] S2. Conduct experiments on the intake valve plate to determine the pressure difference and temperature experienced by the two surfaces of the intake valve plate during intake and compression processes; determine the lateral stress F experienced by the intake valve plate during the piston rod's rocking motion. l (Dynamic simulation can be used to assist in verification).

[0077] In one specific embodiment, the lateral stress F experienced by the intake valve plate in step S2 is... l The value of F is determined by the piston's oscillating acceleration 'a'. l =f() (1)

[0078] The piston's oscillating acceleration 'a' is related to the piston rod length 'l', the crankshaft's angular velocity 'ω', and the crankshaft radius 'r'.

[0079] a=f( ,r,ω) (2)

[0080] The tilt angle of the intake valve plate during the piston intake and compression process is θ; the temperature and pressure of the gas environment in which the intake valve plate is located are constantly changing; the compressor speed is N1; then the cycle length T of the intake and compression process is:

[0081] The angular velocity of the crankshaft is ω:

[0082]

[0083] The crankshaft rotates at an angle α:

[0084]

[0085] The deflection angle is θ:

[0086]

[0087]

[0088] The actual state equation for the air compression process is:

[0089]

[0090] Where: P is the gas pressure; V is the gas volume; n is the number of gas moles; R is the gas constant; T is the Kelvin temperature of the gas; a is the intermolecular attraction parameter; b is the molecular volume parameter;

[0091] The gas volume is the volume of the compression cylinder:

[0092]

[0093] In the formula: h and d are the height and width of the compressor cylinder, respectively;

[0094] The method for calculating the pressure difference across the intake valve plate is as follows:

[0095]

[0096] In the formula: P is the compressed gas pressure, and P0 is the atmospheric pressure.

[0097] S3. Select the life cycle stress model and use the pressure difference, temperature and lateral stress determined in step S2 to calculate the acceleration factor of the intake valve plate.

[0098] In one specific embodiment, the acceleration factor in step S3 is calculated as follows:

[0099] by Using time intervals as units, solve equations (12)-(15) simultaneously to calculate the tilt angles of the piston surface where the intake valve plate is located for each time interval, namely θ1, θ2, ..., θ n′ The gas pressure differences across the valve plate are ΔP1, ΔP2, ΔP3, ..., ΔP n′ Temperatures are T1, T2, ..., T n′ The acceleration factor for each time unit is determined according to formula (5): AF1, AF2, ..., AF n′ Then, by integrating and averaging the acceleration factor over time using formula (16), the acceleration factor of the intake valve plate determined in step S3 is obtained:

[0100]

[0101] Formula (5) is specifically as follows:

[0102]

[0103] In the formula: CθΔP′ is the gas pressure difference during the accelerated test; ΔP is the pressure difference during actual operation; T′ is the gas temperature during the accelerated test; and T is the gas temperature during actual operation.

[0104] S4. Determine the accelerated stress level and the number of valve sample N for the accelerated test of the intake valve plate (Formula 7). In one specific embodiment, firstly, it is necessary to understand that the failure mechanism of the intake valve plate is mainly fatigue failure. Based on this, ensure that the applied accelerated stress can effectively accelerate the fatigue failure process, rather than leading to unexpected failure modes. For fatigue failure of the intake valve plate, the magnitude or frequency of cyclic stress can be increased. Then, determine the accelerated stress level. The accelerated stress level should be higher than the stress level under normal operating conditions to reveal the product's failure behavior in a shorter time. Furthermore, preliminary tests or reference to accelerated test data of intake valve plates from similar compressors should be used to help determine the appropriate stress level range to ensure that the accelerated stress level is not too high, thus avoiding unexpected failure modes. The expected life determined in step S1 can also be used as a reference when determining the accelerated stress level. If the expected life is long, the accelerated stress level can be increased to improve the test speed; conversely, the accelerated stress level should be reduced to make the test time appropriate and improve test efficiency. Finally, conduct preliminary tests, continuously monitoring and evaluating the failure behavior of the intake valve plate during the test to verify whether the selected accelerated stress can effectively accelerate the failure process and observe the failure mode. Finally, the accelerated stress level and the number of valve plate samples N for the accelerated test were determined.

[0105] S5. Based on the determined accelerated stress level and the number of valve plate samples N, conduct accelerated stress tests on the intake valve plates and record the failure time t′ of each intake valve plate during the test. During the accelerated stress test, determine whether the valve plate has failed during the test based on the failure mode, and record the failure time t′.

[0106] S6. Use Weibull lifetime distribution analysis to perform statistical analysis on the failure times t′ of N tests to obtain the lifetime probability distribution of the intake valve plate failure; determine the lifetime characteristic quantity η of the intake valve plate based on the lifetime probability distribution of the intake valve plate failure.

[0107] The basic steps of Weibull lifetime distribution analysis are fixed, and the specific steps are as follows:

[0108] 1) In accelerated life testing, collect N test failure times t';

[0109] 2) Data sorting: Sort the N failure times t' in ascending order;

[0110] Calculate the cumulative distribution function (CDF): Calculate the cumulative probability Pi corresponding to each failure time t' using the following formula:

[0111] Pi=(i-0.5) / N, where i=1,2,...,N;

[0112] 3) Logarithmic transformation: Perform a logarithmic transformation on the failure time t' and the cumulative probability Pi, and calculate ln(t') and ln(-ln(1-Pi));

[0113] 4) Linear regression analysis: Perform linear regression analysis on the scatter plot of ln(t') and ln(-ln(1-Pi)), fit a straight line, and obtain the regression coefficient (slope) and intercept.

[0114] 5) Calculate the characteristic lifetime (η): Based on the results of the linear regression analysis, the estimated value of the characteristic lifetime (η) can be obtained.

[0115] 6) Result analysis: After obtaining the characteristic lifetime (η), the probability distribution of intake valve failure can be described.

[0116] In one specific embodiment, the lifespan characteristic η of the intake valve plate is:

[0117]

[0118] In the formula, A is a constant related to the failure mode and acceleration type; Ea is the activation energy determined by the material properties of the intake valve plate; k is the Boltzmann constant; θ is the tilt angle of the piston rod; C is the correction coefficient; ΔP represents the stress generated by the pressure difference between the inside and outside of the gas in the direction perpendicular to the surface of the intake valve plate.

[0119] In one specific implementation, after obtaining the failure time in S5, statistical analysis, such as Weibull distribution analysis, is performed on the data in S6. By fitting the data points, the value of the constant A is calculated. Specific calculation methods may include least squares method, maximum likelihood estimation, etc.

[0120] S7. Based on the failure time t′ of the N intake valves in step S5 and the acceleration factor obtained in step S3, calculate the expected lifespan t (t=t' / AF) of the N intake valves under normal operating conditions; determine the error ε between the expected lifespan t of the N intake valves under normal operating conditions and the lifespan characteristic quantity η of the intake valves determined in step S6, and determine whether all errors ε are less than the preset value; if there is an error ε greater than the preset value, correct the coefficient parameters in the life cycle stress model.

[0121] In one specific implementation, the number of valve plate samples N is calculated based on the Weibull lifetime distribution model. The characteristic lifetime calculation method at a confidence level of 60% is as follows:

[0122]

[0123] In the formula, x represents the failure degree of the intake valve plate at x%; t″ represents the time required for the intake valve plate to achieve the failure degree of x%; s and N represent the number of failures and the total number of failures of the intake valve plate at the i-th failure time, respectively; h represents the target characteristic lifetime of the intake valve plate; the calculation method for the sample size N is as follows:

[0124]

[0125] In one specific embodiment, the error ε is taken as 10% to 20%; preferably 10%.

[0126] S8. Based on the modified life cycle stress model, repeat steps S3-S7 until the error ε between the expected life t of N intake valves under normal use conditions and the life characteristic quantity η of the intake valve determined in step S6 is within the preset value range. Record the acceleration factor AF at this time as the final determined acceleration factor.

[0127] S9. Based on the final determined acceleration factor AF, repeat steps S4-S5 to conduct an accelerated life test on an intake valve plate and obtain the failure time t′; use the final determined acceleration factor AF to convert the failure time t′ of the accelerated test into the expected life t of the intake valve plate of the automotive suspension system air compressor:

[0128]

[0129] In one specific embodiment, since the compressor of the present invention has an integrated connecting rod and piston design, the piston moves in both vertical and horizontal directions during the intake and compression processes, causing the intake valve plate to be subjected to stress in both vertical and horizontal directions simultaneously. Therefore, in step S3, the Arrhenius life cycle stress model is selected.

[0130] As is known from common technical knowledge, this invention can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative in all respects and are not the only ones. All modifications within the scope of this invention or its equivalents are included in this invention.

Claims

1. A method of accelerated life testing of an air compressor suction valve for an automotive suspension system, characterized by, Comprise: S1, determine the expected life of the suction valve piece under normal use conditions, failure mode; S2, the experimental determination of the suction valve piece in the suction and compression process on both sides of the surface by the pressure difference and temperature; determine the lateral stress on the suction valve piece in the process of piston rod swing; S3, select life cycle stress model, using step S2 to determine the pressure difference, temperature and lateral stress calculation of the suction valve piece of the acceleration factor; S4, determine the acceleration stress level and the number of valve piece samples N of the air compressor suction valve piece of the automobile suspension system; S5, according to the acceleration stress level and the number of valve piece samples N of the suction valve piece, the acceleration stress test is carried out, and the failure time t' of N suction valve pieces in the test process is recorded; S6, using Weibull life distribution analysis to statistically analyze the N test failure time t', so as to obtain the life probability distribution result of the suction valve piece failure; according to the life probability distribution result of the suction valve piece failure, the life characteristic quantity η of the suction valve piece is determined; S7, according to the failure time t' of N suction valve pieces in step S5 and the acceleration factor obtained in step S3, the expected life t of N suction valve pieces under normal use conditions is calculated; judge the error ε of the expected life t of N suction valve pieces under normal use conditions and the life characteristic quantity η of the suction valve piece determined in step S6, judge whether all the errors ε are less than the preset value; if there is an error ε greater than the preset value, the coefficient parameter in the life cycle stress model is modified; S8, on the basis of the modified life cycle stress model, repeat steps S3-S7, until the error ε of the expected life t of N suction valve pieces under normal use conditions and the life characteristic quantity η of the suction valve piece determined in step S6 is within the preset value range, record the acceleration factor AF at this time as the final determined acceleration factor; S9, according to the final determined acceleration factor AF, repeat steps S4-S5 to perform an accelerated life test of an air valve plate, and obtain the failure time t ′ ; using the final determined acceleration factor AF, convert the failure time t of the accelerated test into the expected life t of the air compressor air valve plate of the automobile suspension system: ′ ​ 2. The accelerated life test method for an air compressor suction valve of an automotive suspension system according to claim 1, characterized by, In step S1, the expected life of the suction valve piece under normal use conditions and the failure mode are determined according to the collected historical data.

3. The accelerated life test method for an air compressor suction valve of an automotive suspension system according to claim 1, characterized by, The lateral stress F on the suction valve plate in step S2 l Decided by the swing acceleration a of the piston: F l = f(a) (1) The swing acceleration a of the piston is related to the piston rod length l, the angular velocity ω of the crankshaft rotation and the crankshaft radius r: a = f (l, r, ω) (2) The inclination angle of the suction valve piece in the piston suction and compression process swing is θ, the temperature and pressure of the gas environment where the suction valve piece is located are constantly changing; the speed of the compressor is N1, and the cycle length of the suction compression process is T: The rotation angle of the crankshaft is α: The deflection angle is θ: The actual state equation of the air compression process is: In the formula: P is the gas pressure; V is the gas volume; n is the gas mole number; R is the gas constant; T is the gas Kelvin temperature; a is the intermolecular attraction parameter; b is the molecular volume parameter; The gas volume is the volume of the compression cylinder: In the formula: h and d are the height and width of the compressor cylinder respectively; The calculation method of the pressure difference on both sides of the suction valve piece is as follows: In the formula: P is the compression gas pressure, P0 is the atmospheric pressure. The calculation method of the acceleration factor in step S3 is as follows:

4. The accelerated life test method of an air compressor suction valve of an automotive suspension system according to claim 3, characterized by, In the formula (5), the specific formula is: In The inclination angles of the piston surface where the suction valve plate is located at each time interval are θ1, θ2, …, θn, respectively, the pressure differences of the gas on both sides of the valve plate are ΔP1, ΔP2, ΔP3, …, ΔPn, respectively, the temperatures are T1, T2, …, Tn, respectively, the acceleration factors of each time unit are AF1, AF2, …, AFn, respectively, and the acceleration factor of the suction valve plate determined in step S3 is AF. n′ n′ n′ n′ The acceleration factors of each time unit are AF1, AF2, …, AFn, respectively, and the acceleration factor of the suction valve plate determined in step S3 is AF.​​​ ​ Wherein: CθΔP' is the gas pressure difference of the accelerated test; ΔP is the pressure difference in actual operation; T' is the gas temperature of the accelerated test; T is the gas temperature in actual operation.

5. The accelerated life test method of an air compressor suction valve of an automotive suspension system according to claim 1, wherein In step S3, the Arrhenius life cycle stress model is selected.

6. The accelerated life test method of an air compressor suction valve plate for an automotive suspension system according to claim 1, characterized by, The number N of valve sample is calculated based on the Weibull life distribution model, and the characteristic life calculation method with a confidence of 60% is as follows: Wherein: x is the failure degree of the intake valve, which is x%; t" is the time length required for the failure degree of the intake valve to be x%; s and N are the failure number corresponding to the i th failure time and the total failure number of the intake valve respectively, h is the target characteristic life of the intake valve; and the calculation method of the sample number N is as follows:

7. The accelerated life test method of an air compressor suction valve of an automotive suspension system according to claim 3, characterized by, In step S6, the life characteristic quantity η of the intake valve is as follows: Wherein: A is a constant related to the failure mode and the acceleration type; Ea is the activation energy determined by the material properties of the intake valve; k is the Boltzmann constant; θ is the inclination angle of the piston rod; C is the correction coefficient; and ΔP represents the stress action of the pressure difference between the inside and outside of the gas in the direction perpendicular to the surface of the intake valve.

8. The accelerated life test method of an air compressor suction valve plate for an automotive suspension system according to claim 1, characterized by, In step S7, the value of the error ε is 10% to 20%.

9. The accelerated life test method of an air compressor suction valve plate for an automotive suspension system according to claim 1, characterized by, In step S7, the value of the error ε is 10%.

10. The accelerated life test method of an air compressor suction valve of an automotive suspension system according to claim 1, wherein In step S4, the acceleration stress level of the accelerated life test of the intake valve is greater than the stress level under the normal use condition and less than the stress level at which the unintended failure mode is generated.

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