A method and test bench for testing stability of a tailgate system of a vehicle

Abstract

The application relates to a kind of automobile tail door system stability test method and test bench, method includes the following steps: test vehicle is placed on test bench, test bench is configured to load test vehicle;Obtain the initial performance and objective index of the tail door system of test vehicle;The tail door of test vehicle is positioned at different opening degrees, and different load types are applied to the tail door at different opening degrees;Obtain the test result of the tail door at corresponding opening degree under corresponding load type;And obtain the current performance of the tail door at corresponding opening degree after corresponding load type is applied;Based on the correlation between test result and objective index, and the initial performance and current performance, the stability of automobile tail door system is determined. Through the method provided by the application, the stability of automobile tail door system can be tested in the product design and development stage, so that it meets the product design requirements and improves product quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tailgate system testing, in particular to a tailgate system stability testing method and testing platform. BACKGROUND

[0002] The tailgate of an automobile is a cover member with opening and closing and sealing functions installed at the trunk of the automobile. The common structural type is the hatchback door of a two-door automobile and the luggage compartment cover of a three-door automobile. The tailgate is mainly composed of a tailgate body, a lock body, a hinge, a spring (gas spring or torsion bar spring), and a sealing strip, and is one of the most critical vehicle body closure systems.

[0003] During actual use of the tailgate by a user, the tailgate opening and closing and sealing functions should not fail, and the performance and system stability of the tailgate should be continuously monitored and compared. The system stability is manifested as performance degradation of the tailgate system caused by external load interference, which can be eliminated when the external load interference disappears, i.e., the tailgate system can return to the original performance state. Conversely, if the performance degradation still exists after the external load interference disappears, the system is unstable.

[0004] Therefore, testing the performance stability of the tailgate system after being subjected to external load interference can ensure that the tailgate works normally under various conditions. However, there is no related research on measuring the stability of the tailgate system by automobile manufacturers and research and development teams, and the performance stability and product quality of the tailgate system before and after the automobile is delivered cannot be ensured. SUMMARY

[0005] One of the purposes of the present application is to provide a tailgate system stability testing method for testing the stability of the tailgate system during the product design and development stage, so as to meet the product design requirements and improve the product quality. The second purpose is to provide a testing platform to complete the stability testing of the tailgate system.

[0006] In order to achieve the above purposes, the technical solutions adopted by the present application are as follows:

[0007] The first aspect of the present application provides a tailgate system stability testing method applied to a testing platform, comprising the following steps:

[0008] The test vehicle is placed on the testing platform, and the testing platform is configured to apply a load to the test vehicle;

[0009] The initial performance and objective indicators of the tailgate system of the test vehicle are obtained;

[0010] The tailgate of the test vehicle is positioned at different opening degrees, and different load types are applied to the tailgate at different opening degrees;

[0011] obtaining a test result of the tailgate under a corresponding opening degree under a corresponding load type; and

[0012] obtaining a current performance of the tailgate under the corresponding opening degree after the corresponding load type is applied;

[0013] determining the stability of the tailgate system of the automobile based on the test result and the objective index, and a correlation between the initial performance and the current performance.

[0014] In a preferred technical solution, the initial performance includes a measurement item and a measurement result, and the obtaining of the initial performance of the tailgate system of the test vehicle includes:

[0015] selecting the measurement item of the tailgate system of the test vehicle, the measurement item including at least one of an unlocking bounce height, an opening force, a maximum support height, a closing force, a static locking force, an appearance gap difference, and an abnormal sound evaluation;

[0016] measuring the selected measurement item based on a performance evaluation requirement and a measurement method of a tailgate system development specification, to obtain a measurement result corresponding to the measurement item;

[0017] wherein the measurement item, the performance evaluation requirement, and the measurement method of the initial performance are the same as those of the current performance.

[0018] In a preferred technical solution, the positioning of the tailgate of the test vehicle at different opening degrees and the application of different load types to the tailgate at different opening degrees include:

[0019] positioning the tailgate of the test vehicle at a first opening degree state, and applying a corresponding type of load to the tailgate under the first opening degree state, wherein the first opening degree state represents an opening degree of the tailgate at an unlocking bounce height;

[0020] positioning the tailgate of the test vehicle at a second opening degree state, and applying a corresponding type of load to the tailgate under the second opening degree state, wherein the second opening degree state represents an opening degree of the tailgate at a fully open position.

[0021] In a preferred technical solution, the positioning of the tailgate of the test vehicle at different opening degrees and the application of different load types to the tailgate at different opening degrees include:

[0022] positioning the tailgate of the test vehicle at different opening degrees, and applying a horizontal transverse load and / or an over-opening load to the tailgate at different opening degrees; wherein,

[0023] applying the horizontal lateral load to the tailgate when the tailgate is in a first opening state;

[0024] applying the horizontal lateral load and the over-opening load to the tailgate when the tailgate is in a second opening state.

[0025] In a preferred technical solution, the applying the horizontal lateral load to the tailgate comprises:

[0026] applying zero load to a side corner of a bottom hemmed edge of the tailgate by the test bench;

[0027] gradually applying load to a limit lateral load from the zero load;

[0028] unloading the load to the zero load from the limit lateral load.

[0029] In a preferred technical solution, the gradually applying load to a limit lateral load from the zero load comprises:

[0030] obtaining a first distance between a midpoint of the bottom hemmed edge and a hinge axis of the tailgate in sequence; and,

[0031] obtaining a second distance between a center of gravity of the tailgate and the hinge axis of the tailgate; and,

[0032] obtaining a design weight and a lateral force coefficient of the tailgate;

[0033] calculating the limit lateral load based on the first distance, the second distance, the design weight and the lateral force coefficient;

[0034] gradually applying load to the limit lateral load from the zero load.

[0035] In a preferred technical solution, the applying the over-opening load to the tailgate comprises:

[0036] applying zero load to a midpoint of a bottom hemmed edge of the tailgate in an opening direction of the tailgate by the test bench;

[0037] gradually applying load to a limit over-opening load from the zero load;

[0038] unloading the load to the zero load from the limit over-opening load.

[0039] In a preferred technical solution, the gradually applying load to a limit over-opening load from the zero load comprises:

[0040] obtaining a first distance between a midpoint of the bottom hemmed edge and a hinge axis of the tailgate in sequence; and,

[0041] obtaining a second distance between the center of gravity of the tailgate and a hinge axis of the tailgate; and

[0042] obtaining an overload force at the center of gravity of the tailgate and a design support reaction force at a lock body;

[0043] calculating the limit overload based on the first distance, the second distance, the overload force and the design support reaction force;

[0044] gradually applying a load from the zero load to the limit overload.

[0045] In a preferred technical solution, the obtaining of the test result of the tailgate under a corresponding load type at a corresponding opening degree comprises:

[0046] obtaining a first displacement amount of a corresponding measurement site of the tailgate under the limit lateral load or the limit overload; wherein the corresponding measurement site under the limit lateral load is another side corner of a bottom edge of the tailgate and a single-side hinge of the tailgate, and the corresponding measurement site under the limit overload is both sides of the tailgate;

[0047] obtaining a second displacement amount of a corresponding measurement site of the tailgate after unloading to the zero load;

[0048] judging an interference condition between the tailgate and a vehicle body of the test vehicle;

[0049] obtaining a test result according to the first displacement amount, the second displacement amount and the interference condition.

[0050] The second aspect of the present application provides a test bench for implementing the automobile tailgate system stability test method provided by the first aspect of the present application, the test bench comprising a test bench, a universal loading device, a plurality of standard displacement sensors and a plurality of load-bearing supports, the universal loading device being arranged on the test bench for placing the test vehicle; a plurality of standard displacement sensors are arranged on a plurality of measurement sites of the tailgate of the test vehicle; a plurality of load-bearing supports are arranged on the bottom of the test vehicle.

[0051] The test bench has the same advantages as the automobile tailgate system stability test method described above compared with the prior art, and will not be described here.

[0052] Compared with the prior art, the present application has the following beneficial effects:

[0053] The application provides a kind of automobile tailgate system stability test method, applied to test bench, comprising the following steps: the test vehicle is placed on the test bench, the test bench is configured to load the test vehicle;Obtain the initial performance and objective index of the tailgate system of the test vehicle;The tailgate of the test vehicle is positioned at different opening degrees, and different load types are applied to the tailgate at different opening degrees;Obtain the test results of the tailgate at corresponding opening degrees under corresponding load types;And obtain the current performance of the tailgate at corresponding opening degrees after applying corresponding load types;Based on the test results and the objective index, and the correlation between the initial performance and the current performance, the stability of the automobile tailgate system is determined.

[0054] By the method provided by the application, by loading different load types, different working conditions that the tailgate system may encounter in actual use can be simulated, and calculation and measurement are carried out under corresponding load types, compared with the initial performance and objective index of the tailgate system, the influence of the use of the tailgate by the user under different working conditions on the stability of the tailgate can be tested, and the effectiveness of the test verification is ensured. In this way, more comprehensive evaluation requirements are formulated for the stability of the tailgate system, not only the test results in the test of the stability of the tailgate under multiple loadings are evaluated subjectively and objectively, but also the performance of the tailgate after the test is evaluated subjectively and objectively, covering the design requirements and user needs of the stability of the tailgate, and the sufficiency of the test verification is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0055] In order to more clearly illustrate the technical solutions of the present application, the following will briefly introduce the drawings needed to be used in the description of the present application. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0056] Figure 1 The step flow chart of the automobile tailgate system stability test method described in an embodiment of the present application;

[0057] Figure 2 The overall structure schematic diagram of the test bench described in an embodiment of the present application;

[0058] Figure 3 The spacing schematic diagram of the limit load calculation of the tailgate of common structure type in loading stability test in an embodiment of the present application;

[0059] Figure 4 The measurement site schematic diagram of the tailgate at the first opening degree under transverse loading stability test in an embodiment of the present application;

[0060] Figure 5A measurement site schematic diagram of a transverse loading stability test of the tailgate in the second opening degree state according to an embodiment of the present application;

[0061] Figure 6 A measurement site schematic diagram of a transverse loading stability test of the tailgate in the second opening degree state according to an embodiment of the present application;

[0062] Legend:

[0063] Wherein, 1, test vehicle; 2, test bench; 21, universal loading device; 22, load bearing support. DETAILED DESCRIPTION

[0064] It can be understood that the tailgate is an important functional component of the automobile, and the stability of the tailgate system has important significance and effect. The automobile with good stability can ensure the safety and comfort of the user when using the vehicle; can ensure the functional reliability of the tailgate, avoid opening and closing failure, jamming, blockage and other problems; can improve the durability and service life of the tailgate; can enhance the user's satisfaction with the vehicle, and improve the brand reputation and market competitiveness of the vehicle manufacturer.

[0065] And for the automobile with poor stability, when the user is in some common load scenarios during use, it is easy to affect the tailgate design state, resulting in various performance degradation problems of the tailgate. For example, the problems of insufficient opening assist, decreased support height, and increased appearance step difference after the user forces the tailgate to be fully opened; or the problems of opening vibration and abnormal sound during opening and closing of the tailgate after the vehicle runs on a large torsion road; or the problems of increased closing force and increased appearance gap after the user parks on a side slope or torsion road and uses the tailgate. These performance degradation problems caused by long-term use of the tailgate can easily cause user complaints, and when the degradation is serious, it will affect the opening and closing and sealing function reliability of the tailgate.

[0066] The stability test before the automobile is delivered can objectively evaluate the stability performance of the tailgate system of the automobile, provide quantitative and qualitative data support, avoid the errors caused by the subjective evaluation of the current researchers, and through the test evaluation results, the problems that may occur in the actual use of the tailgate system can be found and solved as soon as possible, so as to comprehensively realize the functions of evaluating performance indicators, discovering potential problems in time, reducing risks and costs, meeting product design requirements, and improving user satisfaction. Therefore, the test verification of the performance stability of the tailgate system after being disturbed by external load in the design and development stage of the tailgate is an important means to ensure the safety, reliability and user experience of the tailgate system.

[0067] Therefore, the present application aims to fill the gap in the field of tailgate system testing today, and provides a tailgate system stability test method. Please refer to Figure 1 .Figure 1 A step flow chart of a method for testing stability of a tailgate system of a vehicle is shown.

[0068] A method for testing stability of a tailgate system of a vehicle, characterized by being applied to a test bench, comprising the following steps:

[0069] S1, placing a test vehicle 1 on a test bench, the test bench being configured to apply a load to the test vehicle 1;

[0070] S2, obtaining initial performance and objective indicators of a tailgate system of the test vehicle 1;

[0071] S3, positioning the tailgate of the test vehicle 1 at different opening degrees, and applying different load types to the tailgate at different opening degrees;

[0072] S4, obtaining test results of the tailgate at corresponding opening degrees under corresponding load types; and

[0073] S5, obtaining current performance of the tailgate at corresponding opening degrees after applying corresponding load types;

[0074] S6, determining stability of the tailgate system of the vehicle based on the test results and the objective indicators, and the correlation between the initial performance and the current performance.

[0075] Specifically, the stability of the tailgate system specifically refers to the ability of the tailgate to maintain its normal function and restore to the original performance state when subjected to external load interference. The load referred to herein is the torque or force that the tailgate of the vehicle is subjected to under common load scenarios, which can come from the external environment or the operation of the user, and a test bench can be used to apply the load. Referring to Figure 2 Figure 2 An exemplary test bench provided according to some embodiments of the present disclosure is shown. The test bench includes a vehicle body partial test bench 2, a universal loading device 21 is installed on the vehicle body partial test bench, the test vehicle 1 is installed on the universal loading device 21, different types of loads can be applied to the vehicle by adjusting the direction and loading force of the universal loading device 21.

[0076] ​The vehicle equipped with the tailgate system can be horizontally placed on the universal loading device 21, and the vehicle is supported to keep the tires off the ground. In some embodiments, a vehicle security support bracket 22 with a load of 1-3T and a height of 300-600mm can be used to support the vehicle to the tire-off-ground state. In some embodiments, the loading range of the universal loading device is not less than ±500N, and X, Y, Z three-direction translation and X, Y, Z three-axis rotation can be achieved, and the translation range can be within 0-2000mm, so as to ensure the rotation freedom of the loading direction and the complete adjustment range covering the tailgate size. In some embodiments, the test vehicle 1 can be a vehicle equipped with a tailgate system, which can be a complete vehicle or a vehicle with some body parts removed, equipped with a complete tailgate system. The complete tailgate system generally includes tailgate, hinge, locking mechanism and sealing parts, etc., which can refer to the system configured in the existing automobile, and will not be described in detail herein. Preferably, the commonly configured structure type of tailgate can select the hatchback door of two-door car and the trunk lid of three-door car.

[0077] The initial performance and objective index of the tailgate system can be obtained according to the performance evaluation requirements and measurement methods of the tailgate system development technical specification. The initial performance can be understood as the performance of the tailgate when the automobile is not disturbed by external load. In some embodiments, the current performance of the tailgate can be obtained by the measurement method of the initial performance, and the current performance can be understood as the performance of the automobile after being disturbed by external load.

[0078] The objective index can be understood as the objective displacement of the tailgate when the automobile is not disturbed by external load. The objective displacement can be a certain range value in the tailgate system development technical specification. In some embodiments, the test results of the tailgate can be obtained, and the test results at least include the displacement of the automobile after being disturbed by external load. In some embodiments, the test results can also include the interference between the tailgate and the vehicle body, and more descriptions of the test results will be embodied in the following.

[0079] By comparing the performance before and after the load disturbance and the displacement, and referring to the performance evaluation requirements, the performance evaluation requirements can dataize the performance and displacement, including various quantitative and qualitative indexes and parameters, and provide a judgment standard, so that the test personnel can objectively evaluate the stability of the tailgate after being disturbed by external load.

[0080] It needs to be explained that in the actual use process, the tailgate system of the automobile will face various external load disturbances. By changing the different types of loads received by the tailgate, the load conditions that the automobile may encounter in the working conditions are simulated. Different load types can be understood as different directions and sizes of loads. Different directions and sizes of loads can be applied to the tailgate through the test bench, so as to realize the evaluation of the performance and stability of the tailgate system in different working conditions.

[0081] It also needs to be explained that in different working conditions, the opening degree of the tailgate is different, and the load distribution and stress condition received by the tailgate are different. The opening degree of the tailgate can be the angle opened by the operator after the tailgate is unlocked. The opening degree range can be nearly 0° to the angle after full opening, wherein the angle after full opening depends on the specific vehicle model and design, and this article does not limit it. Exemplarily, different load types can be applied at different opening degrees. For example, when the tailgate is close to 0°, a force of 10N in the horizontal transverse direction is applied to the tailgate; when the tailgate is fully opened, a force of 10N in the horizontal transverse direction is applied to the tailgate; when the tailgate is fully opened, a force of 50N in the horizontal transverse direction is applied to the tailgate; and when the tailgate is fully opened, a force of 50N in the opening direction of the tailgate is applied.

[0082] More specifically, whether each test result meets the requirements of the objective index is evaluated in sequence, and whether the current performance after the test is equivalent to the initial performance is compared. If both are, it is determined that the system stability is qualified. If any one does not meet the requirements, it is determined that the system stability is unqualified. Wherein, equivalent can be understood as little change or within an acceptable range, that is, it is considered that the tailgate system has no obvious performance degradation in stability. The test result can be obtained by actually measuring a value, and meeting the requirements of the objective index can be considered as the value falling within the above range value.

[0083] In summary, by applying different load types to the tailgate system and according to the measurement requirements, different working conditions that the user may encounter in the actual use process of the tailgate system can be simulated, and the initial performance of the tailgate system and the objective index are compared under the corresponding load type. The influence of the user on the stability of the tailgate in different working conditions can be tested, and the effectiveness of the test verification is ensured. In this way, more comprehensive evaluation requirements for the stability of the tailgate system are established. Not only the test results in the test of the stability of the tailgate are evaluated subjectively and objectively, but also the performance of the tailgate after the test is evaluated subjectively and objectively, covering the design requirements and user needs of the stability of the tailgate, ensuring the sufficiency of the test verification, and filling the gap in the field of tailgate system testing in the prior art.

[0084] In some embodiments, the initial performance includes measurement items and measurement results, and the measurement items include at least one of the following: unlock pop-up height, opening force, maximum support height, closing force, static locking force, appearance gap difference, and abnormal sound evaluation. The measurement results include numerical values of the measurement items. The measurement results corresponding to the measurement items can reflect the influence of the tailgate system after being disturbed by external loads. Specifically, step S2 includes:

[0085] S21, selecting measurement items of the tailgate system of the test vehicle 1;

[0086] S22, measuring the selected measurement items based on the performance evaluation requirements and measurement methods of the tailgate system development technical specification, to obtain measurement results corresponding to the measurement items;

[0087] The measurement items, performance evaluation requirements, and measurement methods of the initial performance and the current performance are the same.

[0088] In this embodiment, the vehicle enterprises are provided with tailgate system development technical specifications, which define the types of measurement items, performance evaluation requirements, and measurement methods. The unlock pop-up height, opening force, maximum support height, closing force, static locking force, appearance gap difference, and abnormal sound evaluation can be used to measure the stability of the tailgate system. According to the tailgate system development technical specification, the initial performance of the tailgate system is measured and evaluated. According to the tailgate system development technical specification, the current performance of the tailgate system can be measured and evaluated.

[0089] It can be understood that the unlock pop-up height can be the height of the tailgate automatically popped up after being unlocked; the opening force can be the force required to open the tailgate; the maximum support height can be the maximum height that the tailgate can maintain in the open state; the closing force can be the force required to close the tailgate; the static locking force can be the locking force of the tailgate in the closed state; the appearance gap difference can be the gap difference between the tailgate and the surrounding vehicle body; and the abnormal sound evaluation can be any abnormal sound or noise generated by the tailgate during opening, closing, or movement.

[0090] When measuring and evaluating the current performance and recording, the measurement items, evaluation requirements, and measurement methods should be consistent with the initial performance. The measurement results are used to evaluate the influence of the tailgate system on the stability during use. For example, when testing and evaluating the opening force, maximum support height, and closing force of the tailgate system without being disturbed by external loads, the opening force, maximum support height, and closing force of the tailgate system after being disturbed by external loads should be tested and evaluated. Specifically, step S5 can include:

[0091] S51, determining the current measurement items to be measured according to the measurement items selected in the initial performance;

[0092] S52, based on the performance evaluation requirements and measurement methods of the tailgate system development technical specification, measure the current measurement items to obtain the measurement results corresponding to the current measurement items.

[0093] In some embodiments, step S3 comprises:

[0094] S31, position the tailgate of the test vehicle 1 at a first opening state, and apply a corresponding type of load to the tailgate in the first opening state; wherein the first opening state represents the opening degree of the tailgate at the unlocking pop-up height;

[0095] S32, position the tailgate of the test vehicle 1 at a second opening state, and apply a corresponding type of load to the tailgate in the second opening state, wherein the second opening state represents the opening degree of the tailgate at the fully open position.

[0096] In this embodiment, the main test is to apply a force of a target direction and a target size to the tailgate when the tailgate is in the first opening state, i.e. the tailgate is opened and positioned at the minimum opening position, usually the tailgate is opened to the distance of 10-100mm from the engagement point of the lock catch to the lock body, or in other words, the initial performance of the tailgate unlocking pop-up height, and to apply a force of a target direction and a target size to the tailgate when the tailgate is in the second opening state, i.e. the tailgate is opened and positioned at the fully open position. By simulating different working conditions at two tailgate opening degrees, the limit state of the tailgate system movement can be tested, so as to comprehensively evaluate its stability.

[0097] In some embodiments, step S3 further comprises:

[0098] S33, position the tailgate of the test vehicle 1 at different opening degrees, and apply a horizontal transverse load and / or an over-opening load to the tailgate in different opening degrees.

[0099] In the embodiment, the load type can include horizontal lateral load and over-opening load, wherein the horizontal lateral load is to apply a horizontal lateral load to the tailgate, and the lateral load stability test working condition and measurement requirement of the tailgate system and the lateral load calculation method can simulate the load boundary condition of the user parking on the side slope and the torsion road or the whole vehicle passing through the large torsion road, so as to test the influence of the lateral load on the user using the tailgate and the stability of the tailgate, and ensure the effectiveness of the test verification. The over-opening load is to apply an over-opening load to the tailgate, and the over-opening load stability test working condition and measurement requirement of the tailgate system and the over-opening load calculation method can simulate the load boundary condition of the user opening the tailgate, so as to test the influence of the over-opening load on the user using the tailgate and the stability of the tailgate, and ensure the effectiveness of the test verification. In the embodiment, the horizontal lateral load and the over-opening load can approximately cover the case of the tailgate system under different external load interference, simulate the possible working condition, and provide more comprehensive and accurate tailgate system performance measurement and evaluation for the user in actual use.

[0100] Referring to Figure 4 , it is illustrated that Figure 4 is a measurement position schematic diagram of the lateral load stability test of the tailgate in the first opening degree state according to the present application; wherein Figure 4 a is a horizontal displacement measurement position of the tailgate bottom edge corner, b is a horizontal displacement measurement position of the tailgate single-side hinge, and c is a horizontal load loading position of the tailgate bottom edge corner. Preferably, step S31 comprises:

[0101] S311, positioning the tailgate of the test vehicle 1 in the first opening degree state, and applying a horizontal lateral load to the tailgate in the first opening degree state to complete the lateral load stability test of the tailgate.

[0102] Referring to Figure 5 and Figure 6 , it is illustrated that Figure 5 is a measurement position schematic diagram of the lateral load stability test of the tailgate in the second opening degree state according to the present application; wherein Figure 5 a is a horizontal displacement measurement position of the tailgate bottom edge corner, b is a horizontal displacement measurement position of the tailgate single-side hinge, and c is a horizontal load loading position of the tailgate bottom edge corner. Figure 6 is a measurement position schematic diagram of the over-opening load stability test of the tailgate in the second opening degree state; Figure 6 a is an opening direction displacement measurement position of the tailgate left-side hinge, b is an opening direction displacement measurement position of the tailgate right-side hinge, c is an opening direction load loading position of the tailgate bottom edge corner, and A is a local enlarged schematic diagram of the measurement position. Preferably, step S32 comprises:

[0103] S321, positioning the tail door of the test vehicle 1 at the second opening state, applying a horizontal lateral load and an over-opening load to the tail door in the second opening state to respectively complete the tail door lateral loading stability test and the over-opening loading stability test.

[0104] In a more specific implementation, the present application provides a lateral loading stability test working condition and measurement requirement, and a lateral load calculation method. The tail door lateral loading stability test in step S33 includes:

[0105] S331, applying zero load to the side corner of the bottom edge of the tail door by the test bench;

[0106] S332, gradually applying load from zero load to the limit lateral load;

[0107] S333, unloading the load from the limit lateral load to zero load.

[0108] More specifically, step S333 can include:

[0109] S3331, setting the number of test points, calculating the lateral load increment based on the number of test points and the limit load;

[0110] S3332, starting from zero load, gradually loading to the limit lateral load with the lateral load increment as the step.

[0111] In the present implementation, the universal loading device 21 of the local vehicle body test bench 2 is adjusted so that the universal loading device 21 can apply a horizontal lateral load at the side corner of the bottom edge of the tail door. The universal loading device 21 starts from zero load and gradually loads to the limit lateral load with the lateral load increment as the step, and then unloads to zero load. The loading and unloading process should be slow and smooth, and the speed should be controlled within 2N / S-10N / S. The number of test points can be the number of tests, and the number of test points can be set to set the lateral load increment. For example, when the limit lateral load is 100N, the number of test points can be set to 10 times, and the lateral load increment is 10N / S.

[0112] Preferably, the limit lateral load can be determined according to Formula One, as shown in Figure 3 , which is a schematic diagram of the spacing when calculating the limit load of the tail door in the loading stability test of the common structure type tail door. Figure 3

[0113] F=(L1 / L2)*c*f1, (One)

[0114] ​Wherein, F is the ultimate lateral load; L1 is the distance between the midpoint of the tailgate bottom edge and the tailgate hinge axis; L2 is the distance between the tailgate center of gravity and the tailgate hinge axis; c is the standard tailgate lateral force coefficient; f1 is the tailgate design weight.

[0115] Preferably, the lateral load increment can be determined according to Formula Two;

[0116] ΔF = F / n, (Two);

[0117] Wherein, ΔF is the lateral load increment; F is the ultimate lateral load; n is the number of test data points.

[0118] In a more specific implementation, the present application provides an over-opening load stability test condition and measurement requirement, and an over-opening load calculation method. The tailgate over-opening load stability test in step S33 includes:

[0119] S334, applying zero load to the tailgate in the direction of opening the tailgate at the midpoint of the tailgate bottom edge by the test bench;

[0120] S335, gradually applying load from zero load to the ultimate over-opening load;

[0121] S336, unloading the load from the ultimate over-opening load to zero load.

[0122] More specifically, step S336 can include:

[0123] S3361, setting the number of test points, and based on the number of test points and the ultimate over-opening load, calculating the over-opening load increment;

[0124] S3362, gradually loading from zero load to the ultimate over-opening load with the over-opening load increment as the step size.

[0125] In the present implementation, the universal loading device 21 of the vehicle body local test bench 2 is adjusted so that the universal loading device 21 can apply an over-opening load to the tailgate in the direction of opening the tailgate at the midpoint of the tailgate bottom edge. When the universal loading device 21 applies an over-opening load to the tailgate in the direction of opening the tailgate from zero load, the over-opening load is gradually loaded to the ultimate over-opening load with the over-opening load increment as the step size, and then unloaded to zero load. The loading and unloading process should be slow and smooth, and the speed should be controlled within 2-10 N / S. The number of test points can be the number of tests, and the over-opening load increment can be set by setting the number of test points. For example, when the over-opening lateral load is 100 N, the number of test points can be set to 10 times, and the over-opening load increment is 10 N / S.

[0126] Preferably, the ultimate over-opening load can be determined according to Formula Three;

[0127] W = (L2 / L1) * w1 + w2, (III)

[0128] wherein, W is the ultimate over-opening load; L1 is the distance between the midpoint of the tailgate bottom edge and the tailgate hinge axis; L2 is the distance between the tailgate center of gravity and the tailgate hinge axis; w1 is the standard overloading force at the tailgate center of gravity; w2 is the designed support reaction force at the tailgate lock body.

[0129] Preferably, the over-opening load increment can be determined according to formula IV;

[0130] ΔW = W / n, (IV)

[0131] wherein, ΔW is the over-opening load increment, W is the ultimate over-opening load; n is the number of test data points.

[0132] Please refer to Figures 4-6 , as a specific explanation of the embodiment, step S4 includes:

[0133] S41, obtaining a first displacement amount of the corresponding measurement position of the tailgate under the ultimate lateral load or the ultimate over-opening load; wherein, the corresponding measurement position under the ultimate lateral load is the other side corner of the tailgate bottom edge and the single side hinge of the tailgate, and the corresponding measurement position under the ultimate over-opening load is the two side hinges of the tailgate;

[0134] S42, obtaining a second displacement amount of the corresponding measurement position of the tailgate after unloading to zero load;

[0135] S43, judging the interference between the tailgate and the vehicle body of the test vehicle 1;

[0136] S44, obtaining the test result according to the first displacement amount, the second displacement amount and the interference condition.

[0137] In the embodiment, the test bench can be configured with a standard displacement sensor with a measurement range of not less than ±50mm for loading stability test, and the first displacement amount and the second displacement amount can be obtained by the standard displacement sensor. In the process of gradually loading the load, after each step of loading, more than 10S should be maintained, then the readings of all standard displacement sensors of the corresponding measurement position are recorded, and whether there is interference between the tailgate and the vehicle body is checked. After unloading, the readings of all standard displacement sensors should also be recorded, and whether there is interference between the tailgate and the vehicle body is checked.

[0138] In the test process of the ultimate lateral load, the standard displacement sensor is arranged in the horizontal direction of the other side corner of the tailgate bottom edge and the single side hinge of the tailgate, so that the horizontal displacement amount of the other side corner of the tailgate bottom edge and the single side hinge of the tailgate can be measured during the loading process.

[0139] The displacement amount collected by the standard displacement sensor when gradually loaded to the limit lateral load is recorded as the first displacement amount, and the displacement amount collected by the standard displacement sensor after unloading to zero load is recorded as the second displacement amount, whether the first displacement amount and the second displacement amount meet the index requirements of the objective displacement amount is judged, and whether interference exists between the tail door and the vehicle body is judged, and the judgment results are taken as the test results.

[0140] In the test process of the limit over-opening load, the standard displacement sensor is arranged in the opening direction of the tail door at both sides of the hinge of the tail door, so that the displacement amount of the tail door in the opening direction of the tail door at both sides of the hinge can be measured during the loading process. The displacement amount collected by the standard displacement sensor when gradually loaded to the limit over-opening load is recorded as the first displacement amount, and the displacement amount collected by the standard displacement sensor after unloading to zero load is recorded as the second displacement amount, whether the first displacement amount and the second displacement amount meet the index requirements of the objective displacement amount is judged, and whether interference exists between the tail door and the vehicle body is judged, and the judgment results are taken as the test results.

[0141] The following several examples of the test method provided by the application are introduced in detail and completely in combination with the drawings:

[0142] Example one:

[0143] A test method for the stability of an automobile tail door system is applied to a test bench and includes the following steps:

[0144] S100, a vehicle equipped with a trunk lid system is prepared, the state and assembly state of each part of the trunk lid system are checked to ensure that the state and assembly state of each part meet the design requirements, and the threaded connection points of the lock body and the hinge of the trunk lid system are fastened according to the minimum value of the tightening torque required by the design, and color marking is performed after fastening;

[0145] As shown in Figure 4 , the vehicle equipped with the trunk lid system is horizontally placed on a vehicle body local rigidity test bench 2, and four automobile security load supports 22 are used to support the vehicle to keep the four wheels off the ground.

[0146] S101, the initial performance of the trunk lid system is measured and evaluated and recorded. The evaluation requirements and measurement methods of each performance should be determined and implemented according to the enterprise's trunk lid system technology development specification.

[0147] S102, open the trunk lid, and adjust the trunk lid to the first opening state, and position it to the minimum opening position, adjust the universal loading device 21 of the vehicle body local test bench 2, so that the universal loading device 21 can apply horizontal lateral load at the corner of the bottom edge of the trunk lid, and arrange standard displacement sensors on the other corner of the bottom edge of the trunk lid and the horizontal direction of the single hinge of the trunk lid, so that the horizontal displacement of the other corner of the bottom edge of the trunk lid and the single hinge of the trunk lid can be measured during loading.

[0148] At the same time, the distance L1 between the midpoint of the bottom edge of the trunk lid and the hinge axis of the trunk lid, and the distance L2 between the center of gravity of the trunk lid and the hinge axis of the trunk lid are measured, and substituted into formula one and formula two to calculate the limit lateral load F and the lateral load increment ΔF.

[0149] By controlling the universal loading device 21 of the vehicle body local stiffness test bench 2, horizontal lateral load is applied to the corner of the bottom edge of the trunk lid from 0, and gradually loaded to the limit lateral load F with the lateral load increment ΔF as the step, and then unloaded to 0, the loading and unloading process should be slow and smooth, and the speed should be controlled within 2-10N / S.

[0150] At the same time, after each step of loading, the readings of the standard displacement sensors of the other corner of the bottom edge of the trunk lid and the single hinge of the trunk lid should be recorded, and the interference between the trunk lid and the vehicle body should be checked. After unloading, the readings of the standard displacement sensors of the other corner of the bottom edge of the trunk lid and the single hinge of the trunk lid should also be recorded, and the interference between the trunk lid and the vehicle body should be checked.

[0151] After the test is completed, the trunk lid is restored to the closed state, and the performance of the trunk lid system after the test is measured and evaluated and recorded, and the measurement content and evaluation requirements and measurement methods should be consistent with the initial performance.

[0152] S103, according to the test results and performance comparison results, evaluate the lateral loading stability of the trunk lid at the minimum opening position.

[0153] The test results include the displacement of the other corner of the bottom edge of the trunk lid and the single hinge of the trunk lid under the limit lateral load and after unloading, and the interference between the trunk lid and the vehicle body. The performance comparison results include the comparison of all initial performance of the trunk lid system and the performance after the test.

[0154] If the displacement amount under the limit lateral load and the displacement amount after unloading of all measurement sites meet the objective displacement amount index requirements, and there is no interference between the luggage cover and the vehicle body, and the performance after the test is equivalent to the initial performance, it is determined that the lateral loading stability of the luggage cover at the minimum opening position is qualified.

[0155] Embodiment Two

[0156] As Figure 5 Embodiment Two, a vehicle tailgate system stability test method is shown, which includes the following steps:

[0157] S200, prepare a vehicle equipped with a hatchback door system, check the state and assembly state of each part of the hatchback door system, ensure that the state and assembly state of each part meet the design requirements, and tighten the threaded connection points of the lock body, hinge and gas spring of the hatchback door system according to the minimum value of the design required tightening torque. After tightening, color marking is performed.

[0158] As Figure 5 shown, the vehicle equipped with the hatchback door system is placed horizontally on the vehicle body local rigidity test bench 2, and the vehicle is supported by four automobile security load supports 22 to keep the four wheels off the ground.

[0159] S201, measure and evaluate the initial performance of the hatchback door system and record it. The evaluation requirements and measurement methods of each performance shall be determined and implemented in accordance with the enterprise's hatchback door system technology development specification.

[0160] S202, open the hatchback door and adjust it to the first opening state so that it is positioned at the fully open position. Then adjust the universal loading device 21 of the vehicle body local test bench 2, so that the universal loading device 21 can apply horizontal lateral load at the bottom edge corner of the hatchback door. And arrange standard displacement sensors on the other side corner of the bottom edge of the hatchback door and the horizontal direction of the single side hinge of the hatchback door, so that the horizontal displacement of the other side corner of the bottom edge of the hatchback door and the single side hinge of the hatchback door can be measured during the loading process.

[0161] At the same time, measure Figure 3 The distance L1 between the midpoint of the bottom edge of the hatchback door and the hinge axis of the hatchback door, and the distance L2 between the center of gravity of the hatchback door and the hinge axis of the hatchback door are shown, and are substituted into Formula One and Formula Two to calculate the limit lateral load F and the lateral load increment AF.

[0162] The universal loading device 21 of the local rigidity test bench 2 is controlled to apply a horizontal transverse load to the corner of the bottom hemmed edge of the hatchback door from 0, and gradually load to the limit transverse load F with a transverse load increment ΔF as a step, and then unload to 0. The loading and unloading process should be slow and smooth, and the speed should be controlled within 2-10 N / S.

[0163] Meanwhile, after each step of loading, the reading of the standard displacement sensor of the other corner of the bottom hemmed edge of the hatchback door and the single-side hinge of the hatchback door should be recorded, and whether there is interference between the hatchback door and the vehicle body should be checked. After unloading, the reading of the standard displacement sensor of the other corner of the bottom hemmed edge of the hatchback door and the single-side hinge of the hatchback door should also be recorded, and whether there is interference between the hatchback door and the vehicle body should be checked.

[0164] After the test is completed, the hatchback door is restored to the closed state, and the post-test performance of the hatchback door system is measured and evaluated and recorded. The measurement content and evaluation requirements and measurement methods should be consistent with the initial performance.

[0165] S203, according to the test results and performance comparison results, evaluate the transverse loading stability of the hatchback door at the fully open position.

[0166] The test results include the displacement of the other corner of the bottom hemmed edge of the hatchback door and the single-side hinge of the hatchback door under the limit transverse load and the displacement after unloading, and the interference between the hatchback door and the vehicle body. The performance comparison results include the comparison of all initial performance of the hatchback door system and the post-test performance.

[0167] If the displacement of all measurement sites under the limit transverse load and the displacement after unloading meet the objective displacement requirement, and there is no interference between the hatchback door and the vehicle body, and the post-test performance is equivalent to the initial performance, it is determined that the transverse loading stability of the hatchback door at the fully open position is qualified.

[0168] Example Three:

[0169] A method for testing the stability of a tailgate system of a vehicle, comprising the following steps:

[0170] S300, step S100 is synchronized;

[0171] S301, step S101 is synchronized;

[0172] S302, as Figure 6As shown, the trunk lid is opened and adjusted to the second opening degree state, and positioned at the fully open position. Then, the universal loading device 21 of the vehicle body local test bench 2 is adjusted so that the universal loading device 21 can apply the over-opening load to the midpoint 3 of the trunk lid bottom edge in the tailgate opening direction. Standard displacement sensors are arranged on both sides of the trunk lid hinge 1 and 2 in the trunk lid opening direction, so that the displacement of both sides of the trunk lid hinge 1 and 2 in the trunk lid opening direction can be measured during loading.

[0173] At the same time, the distance L1 between the midpoint of the trunk lid bottom edge and the trunk lid hinge axis, and the distance L2 between the center of gravity of the trunk lid and the trunk lid hinge axis are measured, and substituted into formula three and formula four to calculate the limit over-opening load W and the over-opening load increment ΔW.

[0174] By controlling the universal loading device 21 of the vehicle body local test bench 2, the midpoint of the trunk lid bottom edge is loaded from 0 to the trunk lid opening direction, and the over-opening load is gradually loaded to the limit over-opening load W with the over-opening load increment ΔW as the step, and then unloaded to 0. The loading and unloading process should be slow and smooth, and the speed should be controlled within 2-10 N / S.

[0175] At the same time, after each step of loading, the readings of the standard displacement sensors of both sides of the trunk lid hinge 1 and 2 are recorded, and the interference between the trunk lid and the vehicle body is checked. After unloading, the readings of the standard displacement sensors of both sides of the trunk lid hinge 1 and 2 are also recorded, and the interference between the trunk lid and the vehicle body is checked.

[0176] After the test is completed, the trunk lid is restored to the closed state, and the post-test performance of the trunk lid system is measured and evaluated and recorded. The measurement content and evaluation requirements and measurement methods should be consistent with the initial performance.

[0177] S304, according to the test results and performance comparison results, evaluate the over-opening load stability of the trunk lid at the fully open position.

[0178] The test results include the displacement of both sides of the trunk lid hinge under the limit over-opening load and the displacement after unloading, and the interference between the trunk lid and the vehicle body. The performance comparison results include the comparison of all initial performance of the trunk lid system and the post-test performance.

[0179] If the displacement of all measurement positions under the limit over-opening load and the displacement after unloading meet the objective displacement requirement, and there is no interference between the trunk lid and the vehicle body, and the post-test performance is equivalent to the initial performance, it is determined that the over-opening load stability of the trunk lid at the fully open position is qualified.

[0180] Reference can be made to Figure 2 The second purpose of the embodiment is to provide a test bench for implementing the automobile tailgate system stability test method as above, the test bench comprising a test bench 2, a universal loading device 21, a plurality of standard displacement sensors and a plurality of load-bearing supports 22, the universal loading device 21 being arranged on the test bench 2 for placing the test vehicle 1; the plurality of standard displacement sensors being arranged on a plurality of measurement positions of the tailgate of the test vehicle 1; and the plurality of load-bearing supports 22 being arranged on the bottom of the test vehicle 1.

[0181] For the test bench embodiment of the present application, it is basically similar to the automobile tailgate system stability test method embodiment, so the description is relatively simple, and the relevant parts are described in the method embodiment.

[0182] It should be noted that each embodiment in the present specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same parts of each embodiment can be referred to each other.

[0183] It should also be noted that in this paper, the terms "upper", "lower", "left", "right", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the present application. In addition, relationship terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations, nor can it be understood as indicating or implying relative importance. Moreover, the term "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or terminal device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or terminal device.

[0184] The above provides a kind of automobile tailgate system stability test method and test bench provided in the present application, which is described in detail, specific examples are applied in the present application to describe the principle and implementation mode of the present application, the above embodiment is only used to help understanding the present application, and the content of the specification should not be understood as limiting the present application. At the same time, for those skilled in the art, according to the present application, there will be different forms of changes in specific implementation and application range, which do not need and cannot enumerate all the implementation ways here, and the obvious changes or changes derived therefrom are still within the protection scope of the present application.

Claims

1. A method for testing the stability of a car tailgate system, characterized in that, When applied to a test bench, the following steps are included: The test vehicle is placed on the test bench, which is configured to apply a load to the test vehicle; Obtain the initial performance and objective indicators of the tailgate system of the test vehicle; The tailgate of the test vehicle was positioned at different opening degrees, and different types of loads were applied to the tailgate at different opening degrees. Obtain the test results of the tailgate under the corresponding load type at the corresponding opening degree; and Obtain the current performance of the tailgate at the corresponding opening degree after applying the corresponding load type; Based on the test results and objective indicators, as well as the correlation between the initial performance and the current performance, the stability of the vehicle tailgate system is determined. The step of positioning the tailgate of the test vehicle at different opening degrees and applying different types of loads to the tailgate at different opening degrees includes: The tailgate of the test vehicle was positioned at different opening degrees, and horizontal lateral loads and / or over-opening loads were applied to the tailgate at different opening degrees; wherein, When the tailgate is in the first opening state, the horizontal lateral load is applied to the tailgate; When the tailgate is in the second opening state, the horizontal lateral load and the over-opening load are applied to the tailgate.

2. The method for testing the stability of a car tailgate system according to claim 1, characterized in that, The initial performance includes measurement items and measurement results. Obtaining the initial performance of the tailgate system of the test vehicle includes: The measurement items selected for the tailgate system of the test vehicle include at least one of the following: unlocking pop-up height, opening force, maximum support height, closing force, static locking force, appearance gap step difference, and abnormal noise evaluation. Based on the performance evaluation requirements and measurement methods of the tailgate system development technical specifications, the selected measurement items are measured to obtain the measurement results for the corresponding measurement items. The initial performance and the current performance have the same measurement items, performance evaluation requirements and measurement methods.

3. The method for testing the stability of a car tailgate system according to claim 1, characterized in that, The step of positioning the tailgate of the test vehicle at different opening degrees and applying different types of loads to the tailgate at different opening degrees includes: The tailgate of the test vehicle is positioned in a first opening state, and a load of the corresponding type is applied to the tailgate in the first opening state; wherein, the first opening state is characterized by the opening degree of the tailgate at the unlocked pop-up height; The tailgate of the test vehicle is positioned in a second opening state, and a load of the corresponding type is applied to the tailgate in the second opening state, wherein the second opening state is characterized by the opening degree of the tailgate in the fully open position.

4. The method for testing the stability of a car tailgate system according to claim 1, characterized in that, The application of a horizontal lateral load to the tailgate includes: A zero load is applied to one corner of the bottom edge of the tailgate using the test bench; Gradually apply the load from the zero load to the ultimate lateral load; The load is unloaded from the ultimate lateral load to the zero load.

5. The method for testing the stability of a car tailgate system according to claim 4, characterized in that, The stepwise application of load from zero load to ultimate lateral load includes: The first distance between the midpoint of the bottom edge and the hinge axis of the tailgate is obtained sequentially; and, Obtain the second distance between the center of gravity of the tailgate and the hinge axis of the tailgate; and, Obtain the design weight and lateral force coefficient of the tailgate; The ultimate lateral load is calculated based on the first spacing, the second spacing, the design weight, and the lateral force coefficient. The load is gradually applied from the zero load to the ultimate lateral load.

6. The method for testing the stability of a car tailgate system according to claim 1, characterized in that, The application of an over-opening load to the tailgate includes: A zero load is applied to the midpoint of the bottom edge of the tailgate in the direction of tailgate opening using the test bench; Gradually apply the load from the zero load to the ultimate overload; The load is unloaded from the ultimate overload to the zero load.

7. The method for testing the stability of a car tailgate system according to claim 6, characterized in that, The stepwise application of load from zero load to the ultimate overload includes: The first distance between the midpoint of the bottom edge and the hinge axis of the tailgate is obtained sequentially; and, Obtain the second distance between the center of gravity of the tailgate and the hinge axis of the tailgate; and, Obtain the overload force at the center of gravity of the tailgate and the design support reaction force at the lock body; The ultimate over-opening load is calculated based on the first spacing, the second spacing, the overload force, and the design support reaction force. The load is gradually applied from the zero load to the ultimate overload.

8. A method for testing the stability of a car tailgate system according to claim 4 or 6, characterized in that, The process of obtaining the test results of the tailgate under the corresponding load type at the corresponding opening degree includes: Obtain the first displacement of the measuring part corresponding to the ultimate lateral load or the ultimate over-opening load of the tailgate; wherein, the measuring part corresponding to the ultimate lateral load is the corner on the other side of the bottom edge of the tailgate and the single-side hinge of the tailgate, and the measuring part corresponding to the ultimate over-opening load is the hinges on both sides of the tailgate. Obtain the second displacement of the measurement point corresponding to the tailgate after it is unloaded to zero load; Determine the interference between the tailgate and the body of the test vehicle; The test results are obtained based on the first displacement, the second displacement, and the interference.

9. A test stand, characterized in that, The test bench is used to implement the stability test method for the automobile tailgate system as described in any one of claims 1-8. The test bench includes a test bench, a universal loading device, multiple standard displacement sensors and multiple load-bearing supports. The universal loading device is disposed on the test bench and is used to place the test vehicle. Multiple standard displacement sensors are used to be installed on multiple measuring points on the tailgate of the test vehicle; multiple load-bearing brackets are used to be installed on the bottom of the test vehicle.

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