Cab suspension stiffness detection method and system

Abstract

The application discloses a cab suspension rigidity detection method and system, which comprises the following steps: formulating an excitation scheme according to the structure characteristics of a cab suspension to be detected; selecting the number and connecting points of rigidity detection devices for detecting the cab suspension to be detected according to the excitation scheme; controlling the cab suspension to move downwards for multiple times; collecting data of each time when the cab suspension moves downwards; processing the data according to a segmented displacement method or a total displacement method to obtain rigidity detection results of the cab suspension, so that the detection cost is reduced and the detection efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cab suspension stiffness detection, and particularly relates to a cab suspension stiffness detection method and system. BACKGROUND

[0002] With the gradual improvement of domestic productivity, the demand for commercial vehicles in the logistics transportation is gradually increasing. At present, there are various types of vehicles on the market, and the products with better smoothness and ride comfort can undoubtedly greatly improve their competitiveness in the market. The stiffness of the cab suspension is one of the key parameters affecting the vibration isolation performance of the cab, and the accuracy of the parameter directly affects the accuracy and effectiveness of the subsequent cab smoothness analysis of the driver. At present, there is no special commercial vehicle cab suspension stiffness detection device in China, and most enterprises use hydraulic durability tables to measure the stiffness of the cab suspension. However, the universality of the hydraulic durability table is poor, and the precision and stability of the loading force cannot be guaranteed, which seriously affects the cab suspension stiffness detection effect.

[0003] Moreover, the hydraulic durability machines used by most enterprises at present are expensive, and different types of hydraulic durability machines need to be selected according to the type of the vehicle to detect the stiffness of the cab suspension, which is too high in testing cost and has poor applicability. In the detection process, the detection steps are complex, and the detection efficiency is low. SUMMARY

[0004] The present application provides a cab suspension stiffness detection method and system, which improves the detection efficiency and reduces the detection cost.

[0005] To achieve the above-mentioned purpose, the present application provides a cab suspension stiffness detection method, which is suitable for a stiffness detection system; wherein the stiffness detection system comprises a cab suspension mechanism and a plurality of stiffness detection devices which are fixed and connected according to a preset excitation scheme.

[0006] The test method comprises:

[0007] The horizontal state of the cab suspension mechanism is adjusted, so that the cab suspension mechanism and the ground are kept in a horizontal state;

[0008] The plurality of stiffness detection devices are adjusted respectively, so that each stiffness detection device is in a pre-tightening state; the pre-tightening state is that there is no shaking and loosening between the structures of the stiffness detection device;

[0009] The plurality of stiffness detection devices are controlled to make the cab suspension mechanism connected to the stiffness detection devices move downward for multiple times, and the distance of each downward movement is the same;

[0010] Control each said stiffness detection device to collect the tension required by said cab suspension mechanism during each time of downward movement until said cab suspension mechanism reaches a preset position, and obtain tension data;

[0011] According to said tension data and the distance of each time of downward movement, take segmented displacement method or total displacement method to obtain the stiffness test result of said cab suspension mechanism.

[0012] The cab suspension mechanism is connected with multiple stiffness detection devices in the application, and the stiffness test result of the cab suspension mechanism is obtained through the stiffness detection devices. Firstly, the excitation scheme is formulated according to the structural characteristics of the cab suspension mechanism, and the cab suspension mechanism is connected with the stiffness detection devices according to the excitation scheme, so that the cab suspension mechanism will not appear large elastic deformation during the test process, and the accuracy of the test is ensured. Then, the cab suspension mechanism is adjusted to keep horizontal with the ground, so that the horizontal downward movement during the test process is ensured, and the experimental error caused by the inclination of the cab suspension mechanism is avoided, and the accuracy of the detection is improved. Then, the distance of each time of downward movement of the cab suspension mechanism is controlled to be the same, and the tension required by the cab suspension mechanism during each time of downward movement is obtained and recorded, which provides data support for the analysis of the stiffness of the cab suspension mechanism. Then, according to the research requirements, segmented displacement method or total displacement method can be taken to process data, and more detailed stiffness test result of the cab suspension mechanism is obtained. The whole test process has simple steps, short test time, and improves the detection efficiency.

[0013] As a preferred example, the cab suspension mechanism and multiple stiffness detection devices fixed and connected according to the preset excitation scheme specifically include:

[0014] When the cab suspension mechanism has left and right asymmetric rigid structural members, or the symmetric rigid structural members of the cab suspension mechanism and the stiffness detection device installation have motion interference and cannot find symmetric excitation points, an isosceles triangle three-point excitation scheme is adopted.

[0015] The isosceles triangle three-point excitation scheme is that two excitation points are arranged at the suspension end with symmetrically distributed rigid structural members or without spatial interference of the installation structure, and the midpoint of the balance rod of the suspension end without symmetrically distributed rigid structural members is selected as the third excitation point, so that the three excitation points form an isosceles triangle.

[0016] When the left and right sides of the cab suspension mechanism have symmetric rigid structural members and the symmetric rigid structural members and the stiffness detection device installation space have no motion interference of the mechanism, a symmetric four-point excitation scheme is adopted.

[0017] The symmetric four-point excitation scheme is that four excitation points are established at the suspension and rear suspension floor beam support and cab floor beam mounting points, respectively.

[0018] The present application formulates an excitation scheme suitable for the cab suspension mechanism by analyzing the structure of the cab suspension mechanism to be detected, determines the excitation points according to the excitation scheme, ensures that a suitable excitation scheme can be obtained for any type of cab suspension mechanism, and connects the stiffness detection device, thereby improving the applicability of the stiffness detection device.

[0019] As a preferred example, the cab suspension mechanism and the plurality of stiffness detection devices fixed and connected according to the preset excitation scheme specifically include:

[0020] According to the analysis of the structure of the cab suspension mechanism, a corresponding excitation scheme is adopted, and the positions and quantities of a plurality of excitation points of the cab suspension mechanism are determined according to the excitation scheme;

[0021] According to the positions and quantities of the plurality of excitation points, a plurality of stiffness detection devices are determined, and the plurality of stiffness detection devices are connected and fixed with the cab suspension mechanism through the plurality of excitation points.

[0022] The present application determines the quantity and connection position of the stiffness detection device connected with the cab suspension mechanism through the determined excitation points, which on the one hand ensures the stability of the cab suspension mechanism during measurement, avoids measurement errors caused by shaking of the cab suspension mechanism during measurement, and on the other hand connects the cab suspension mechanism and the stiffness detection device according to the excitation points, avoids large elastic changes of the cab suspension mechanism components, and improves the measurement accuracy.

[0023] As a preferred example, the cab suspension mechanism is kept in a horizontal state with the ground by adjusting the horizontal state of the cab suspension mechanism, specifically including:

[0024] The air bags of the front suspension and the rear suspension of the cab suspension mechanism are pressurized and raised, and the pressurization is stopped when the air bags of the front suspension and the rear suspension rise to the working height of the corresponding real vehicle of the cab suspension mechanism.

[0025] The floor beam and the balance of the cab suspension mechanism are kept horizontal with the ground by fine-tuning the air valve of the air bag.

[0026] The present application controls the front suspension and rear suspension of the cab suspension mechanism to be in the same horizontal plane and to be kept in a horizontal state with the ground, makes the whole cab suspension mechanism force balanced, avoids the front and rear suspension force imbalance, causes measurement error, and uses the air bag inflation to make the cab suspension mechanism in a horizontal state, which is simple in operation, simplifies the workload, and improves the measurement efficiency.

[0027] As a preferred example, before the cab suspension mechanism is controlled to move down multiple times, the present application comprises:

[0028] Each of the multiple stiffness detection devices comprises a displacement sensor and a tension sensor;

[0029] The displacement sensor and the tension sensor on each stiffness detection device are connected to the cab suspension mechanism through the excitation points obtained by the excitation scheme.

[0030] In the present application, the displacement sensor and the tension sensor are connected to the cab suspension mechanism through the excitation points, which ensures the stability during the whole test process and avoids errors, and uses the displacement sensor and the tension sensor to obtain direct data, which simplifies the detection steps and improves the detection efficiency.

[0031] As a preferred example, the distance of each time is the same and the tension required by the cab suspension mechanism when moving down each time, specifically comprising:

[0032] The multiple stiffness detection devices control the distance of each time of the cab suspension mechanism to be the same through the displacement sensor;

[0033] The displacement sensor monitors the descent displacement of each excitation point, so that the displacement of each excitation point is the same, the horizontal state of the cab suspension mechanism is maintained, and the cab suspension mechanism is controlled to descend the same displacement each time;

[0034] The multiple stiffness detection devices obtain the tension required by the cab suspension mechanism when moving down each time through the tension sensor.

[0035] The present application controls the distance of each time of the cab suspension mechanism to be the same through the displacement sensor, which is simple in operation, and the displacement sensor and the cab suspension mechanism are connected through the excitation points, the distance of each time of the excitation points is controlled to be the same, and then the cab suspension mechanism is controlled to move horizontally, which ensures the stability during the whole test process and avoids errors, and the tension required by the cab suspension mechanism when moving down the same distance each time is obtained through the tension sensor, which obtains direct data and improves the detection efficiency.

[0036] As a preferred example, in the rigidity test of the cab suspension mechanism by the piecewise displacement method or the total displacement method, specifically includes:

[0037] If the local change trend of the rigidity of the cab suspension mechanism after each displacement is studied, the piecewise displacement method is used to process the data, and the local change trend of the rigidity of the cab suspension mechanism is obtained.

[0038] If the overall change trend of the rigidity of the cab suspension mechanism from the static state to the preset position is studied, the total displacement method is used to process the data, and the overall change trend of the rigidity of the cab suspension mechanism is obtained.

[0039] According to the needs of the study, the present application adopts different processing methods. When the local change trend of the rigidity of the cab suspension mechanism after each displacement is studied, the piecewise displacement method is used to process the data. When the overall change trend of the rigidity of the cab suspension mechanism from the static state to the preset position is studied, the total displacement method is used to process the data. The present application can obtain more detailed and accurate measurement results of the cab suspension mechanism, and improve the measurement accuracy.

[0040] On the other hand, the present application also provides a cab suspension rigidity detection system for executing the cab suspension rigidity detection method of the present application, wherein the rigidity detection device comprises a fixed base, a height adjusting mechanism, a flower basket bolt fine adjustment mechanism, a sensor fixing mechanism and a fixed top cover.

[0041] The fixed base is connected and fixed with the cast iron floor through bolts, and is used for fixing the rigidity detection device.

[0042] The height adjusting mechanism is connected with the fixed base and the flower basket bolt fine adjustment mechanism through threads, and is used for adjusting the height of the rigidity detection device.

[0043] The flower basket bolt fine adjustment mechanism is used for pre-tightening through the flower basket bolt, i.e. eliminating the matching error between mechanisms, and can control and stabilize the displacement of the cab suspension mechanism through the flower basket bolt.

[0044] The sensor fixing mechanism is connected with the flower basket bolt fine adjustment mechanism downward through threads, and is connected with the fixed top cover upward, and is used for installing and fixing the measurement sensor.

[0045] The fixed top cover is connected and fixed with the cab suspension mechanism floor beam through bolts, and is used for connecting and fixing the rigidity detection device and the cab suspension mechanism.

[0046] The application provides a cab suspension rigidity detection system, which comprises a rigidity detection device, the rigidity detection device comprises a fixed base, a height adjusting mechanism, a flower basket bolt fine adjustment mechanism, a sensor fixing mechanism and a fixed top cover, the fixed base and the fixed top cover are used for fixing and connecting the rigidity detection device with a floor and a cab suspension mechanism to be detected, so that the cab suspension mechanism to be detected is prevented from shaking during measurement, and measurement error is reduced, then the height adjusting mechanism and the flower basket bolt fine adjustment mechanism are used for controlling the height change and height stability of the rigidity detection device during measurement, so that stability during testing is ensured, the height adjusting mechanism and the flower basket bolt fine adjustment mechanism are operated through a flower basket bolt and a thread, operation steps are simple, detection time is saved, the sensor fixing mechanism is used for fixing a sensor and obtaining test data during detection, the rigidity detection device has simple structure, the cost of various components is low, detection cost is reduced, and the rigidity detection device is connected with the cab suspension mechanism through the fixed top cover, is suitable for the cab suspension mechanism, and has strong applicability.

[0047] As a preferred example, the fixed base further comprises a pull wire displacement sensor.

[0048] The pull wire displacement sensor is fixed on the fixed base through a bolt, and is used for controlling the displacement of the cab suspension mechanism connected to the rigidity detection device to be the same during each time of downward movement.

[0049] The pull wire displacement sensor fixed on the fixed base is used for controlling the distance of the cab suspension mechanism to be the same during each time of downward movement, reducing test error and improving detection accuracy, the pull wire displacement sensor has obvious data display, simple structure and low detection cost.

[0050] As a preferred example, the sensor fixing mechanism further comprises a tension sensor.

[0051] The tension sensor is connected and fixed with the sensor fixing mechanism and a fixed clamp on the cab suspension mechanism through a thread, and is used for measuring the tension required by the cab suspension mechanism during each time of downward movement by the same distance.

[0052] The tension sensor is used for obtaining the tension required by the cab suspension mechanism during each time of downward movement by the same distance, the device has simple structure, and according to the simple and easily obtained tension data, the rigidity detection device is provided with accurate and easily obtained data for analyzing the rigidity of the cab suspension mechanism, measurement efficiency is improved, and measurement cost is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0053] Figure 1A flowchart of a cab suspension stiffness detection method provided by the embodiment of the present application is shown in the figure.

[0054] Figure 2 A structure diagram of a stiffness detection device of a cab suspension stiffness detection system provided by the embodiment of the present application is shown in the figure.

[0055] Figure 3 A diagram of a stiffness detection device provided by the embodiment of the present application is shown in the figure.

[0056] Figure 4 A diagram of an isosceles triangle three-point excitation scheme provided by the embodiment of the present application is shown in the figure.

[0057] Figure 5 A diagram of a symmetric four-point excitation scheme provided by the embodiment of the present application is shown in the figure.

[0058] Figure 6 A diagram of results after data processing by using a segmented displacement method provided by the embodiment of the present application is shown in the figure.

[0059] Figure 7 A diagram of results after data processing by using a total displacement method provided by the embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0060] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0061] Embodiment one

[0062] Please refer to Figure 1 A flowchart of a cab suspension stiffness detection method provided by the embodiment of the present application is shown in the figure, which mainly includes steps 101 to 105, and specifically includes:

[0063] Step 101: Adjust the horizontal state of the cab suspension mechanism, so that the cab suspension mechanism and the ground are kept in a horizontal state.

[0064] In this embodiment, before this step, an excitation scheme suitable for the cab suspension is selected according to the structural characteristics of the cab suspension, the excitation scheme including an isosceles triangle three-point excitation scheme and a symmetric four-point excitation scheme, and a diagram of the isosceles triangle three-point excitation scheme is shown in the figure. Figure 4 In the figure, 4-1 is a tension sensor, 4-2 is a tension line displacement sensor, 4-3 is a fixed roof, and 4-4 is a floor beam of the cab.Figure 4 A schematic diagram of an isosceles triangle three-point excitation scheme provided for an embodiment of the present application, two excitation points are provided at the suspended ends of the symmetrically distributed rigid structural members or the installation structure without spatial interference, and the midpoint of the balance bar at the suspended end of the non-symmetrically distributed rigid structural member is selected as the third excitation point, so that the three excitation points form an isosceles triangle, and the stiffness detection device is connected according to the three points. The symmetric four-point excitation scheme is as follows Figure 5 , Figure 5 A schematic diagram of a symmetric four-point excitation scheme provided for an embodiment of the present application, wherein 5-1 is a tension sensor, 5-2 is a tension line displacement sensor, 5-3 is a fixed top cover, and 5-4 is a floor beam of the cab, four excitation points are established at the suspended and rear suspended floor beam support and cab floor beam mounting points, and the stiffness detection device is connected according to the four excitation points.

[0065] In this embodiment, step 101 is specifically: by inflating gas into the air bag of the cab suspension mechanism, the air bags of the front suspension and the rear suspension of the cab suspension mechanism are pressurized and raised, and when the air bags of the front suspension and the rear suspension are raised to the working height of the corresponding vehicle of the cab suspension mechanism, the pressurization is stopped; by fine-tuning the air valve of the air bag, the floor beam and the balance bar of the cab suspension mechanism are kept horizontal with the ground.

[0066] Step 102: adjust the plurality of stiffness detection devices respectively, so that each stiffness detection device is in a pre-tightened state.

[0067] In this embodiment, this step is specifically: according to the determined excitation scheme, the number of stiffness detection devices connected to the cab suspension mechanism is determined, and before connection, all stiffness detection devices are adjusted to ensure that there is no shaking and loosening of the structures on all stiffness detection devices.

[0068] Step 103: control the plurality of stiffness detection devices to make the cab suspension mechanism connected to the stiffness detection devices move down multiple times, and the distance of each time is the same.

[0069] In this embodiment, this step is specifically: the plurality of stiffness detection devices control the cab suspension mechanism to move down the same distance each time through the displacement sensor; the displacement sensor monitors the downward displacement of each excitation point, so that the displacement of each excitation point is the same, the horizontal state of the cab suspension mechanism is maintained, and the cab suspension mechanism is controlled to move down the same displacement each time.

[0070] In the embodiment, the plurality of rigidity detection devices each include a displacement sensor, the displacement sensor in each of the plurality of rigidity detection devices is connected to the cab suspension mechanism through an excitation point, and then the displacement sensor controls the cab suspension to move downward horizontally multiple times with the same distance each time.

[0071] Step 104: control each of the rigidity detection devices to collect the tension required by the cab suspension mechanism each time it moves downward until the cab suspension mechanism reaches a preset position, and obtain tension data.

[0072] In the embodiment, the plurality of rigidity detection devices each include a displacement sensor, the displacement sensor in each of the plurality of rigidity detection devices is connected to the cab suspension mechanism through an excitation point, and then the displacement sensor controls the cab suspension to move downward horizontally multiple times with the same distance each time.

[0073] In the embodiment, the plurality of rigidity detection devices each include a displacement sensor, the displacement sensor in each of the plurality of rigidity detection devices is connected to the cab suspension mechanism through an excitation point, and then the displacement sensor controls the cab suspension to move downward horizontally multiple times with the same distance each time.

[0074] Step 105: according to the tension data and the distance each time the cab suspension mechanism moves downward, obtain the rigidity test result of the cab suspension mechanism by using a segmented displacement method or a total displacement method.

[0075] In the embodiment, if the local rigidity change trend of the cab suspension mechanism after moving downward a certain distance is studied, the segmented displacement method is used to process the data to obtain the local rigidity change trend of the cab suspension mechanism; if the overall rigidity change trend of the cab suspension mechanism from a static state to a preset position is studied, the total displacement method is used to process the data to obtain the overall rigidity change trend of the cab suspension mechanism.

[0076] In the embodiment, after the tension sensor and the tension sensor obtain the data during the downward movement of the cab suspension mechanism, the local rigidity change trend of the cab suspension mechanism is obtained by using the segmented displacement method to process the data as shown in Figure 6 , Figure 6 The result obtained by using the segmented displacement method to process the data provided in the embodiment of the application is shown in Figure 7 , Figure 7 The result obtained by using the total displacement method to process the data provided in the embodiment of the application is shown in

[0077] In the embodiment, the segmented displacement method is as follows:

[0078] In the embodiment, the segmented displacement method is as follows:

[0079] wherein i (i = 1, 2, C, n) represents the number of times of lowering the cab by a certain distance; represents the local equivalent stiffness of the cab suspension at the i-th measurement; F i represents the average value of all force sensors at the i-th and i-1-th lowering, respectively, wherein F0 represents the average value of all force sensors at the initial pre-tightening state; D i-1 represents the average value of all force sensors at the i-th and i-1-th lowering, respectively, wherein F0 represents the average value of all force sensors at the initial pre-tightening state; D i represents the average value of all force sensors at the i-th and i-1-th lowering, respectively, wherein F0 represents the average value of all force sensors at the initial pre-tightening state; D i-1 represents the average value of all force sensors at the i-th and i-1-th lowering, respectively, wherein F0 represents the average value of all force sensors at the initial pre-tightening state; D

[0080] In the present embodiment, the total displacement method is as follows:

[0081]

[0082] wherein j (j = 1, 2,..., n) represents the number of times of lowering the cab by a certain distance; represents the global equivalent stiffness of the cab suspension at the j-th lowering; F j represents the average value of all force sensors at the j-th lowering; F0 represents the average value of all force sensors at the initial pre-tightening state; D j represents the average value of all force sensors at the j-th lowering; F0 represents the average value of all force sensors at the initial pre-tightening state; D

[0083] Please refer to Figure 2 , a structure diagram of a stiffness detection device of a cab suspension stiffness detection system provided by the embodiment of the present application, which mainly comprises a fixed base 201, a height adjusting mechanism 202, a flower basket bolt fine adjustment mechanism 203, a sensor fixing mechanism 204 and a fixed top cover 205.

[0084] In the present embodiment, the fixed base 201 is connected and fixed with the cast iron floor through bolts, for fixing the stiffness detection device.

[0085] The height adjusting mechanism 202 is connected with the fixed base 201 and the flower basket bolt fine adjustment mechanism 203 through threads, for adjusting the height of the stiffness detection device.

[0086] The flower basket bolt fine adjustment mechanism 203 is used for pre-tightening, i.e. eliminating the matching error between mechanisms, and can control and stabilize the displacement amount of the cab suspension lowering through the flower basket bolt.

[0087] The sensor fixing mechanism 204 is connected to the fixed top cover 205 through screw thread connection, and is used for fixing the installation of the measuring sensor.

[0088] The fixed top cover 205 is connected and fixed to the cab suspension mechanism floor beam through bolts, and is used for connecting and fixing the stiffness detection device and the cab suspension mechanism.

[0089] In the embodiment, the fixed base 201 further comprises a pull-wire displacement sensor.

[0090] The pull-wire displacement sensor is fixed to the fixed base through bolts, and is used for controlling the displacement of the cab suspension mechanism connected to the stiffness detection device to be the same each time.

[0091] In the embodiment, the sensor fixing mechanism 204 further comprises a tension sensor.

[0092] The tension sensor is connected and fixed to the sensor fixing mechanism and the fixed clamp on the cab suspension mechanism through screw thread, and is used for measuring the tension required by the cab suspension mechanism when moving down by the same distance each time.

[0093] In the embodiment, the fixed base and the fixed top cover fix and connect the stiffness detection device to the floor and the cab suspension mechanism to be detected, prevent the cab suspension mechanism to be detected from shaking during the measurement, and reduce the measurement error. Then, the height adjusting mechanism and the basket bolt fine adjustment mechanism control the height change and the height stability of the stiffness detection device during the measurement, ensure the stability during the test, and the height adjusting and the basket bolt fine adjustment mechanism are operated through basket bolts and screw threads, the operation steps are simple, the detection time is saved, the sensor is fixed by the sensor fixing mechanism, and the test data during the detection is obtained. The stiffness detection device has simple structure, low cost of each component, and low detection cost. Moreover, the stiffness detection device is connected to the cab suspension mechanism through the fixed top cover, is suitable for the type of cab suspension mechanism, and has strong applicability.

[0094] Please refer to Figure 3 for a schematic diagram of a stiffness detection device provided by the embodiment of the present application.

[0095] In the embodiment, the rigidity detection device is provided with a fixed base 3-1, a pull wire type displacement sensor 3-2, a height adjusting mechanism 3-3, a basket bolt 3-4, a sensor fixing mechanism 3-5, a tension sensor 3-6, and a fixed top cover 3-7. The fixed base 3-1 is connected with the height adjusting mechanism 3-3 through a thread, the height adjusting mechanism 3-3 is connected with the pull wire type displacement sensor 3-2 and the basket bolt 3-4 through a thread, the basket bolt 3-4 is connected with the two ends of the sensor fixing mechanism 3-5 through a thread, the upper end of the tension sensor 3-6 is connected with the excitation point position of the cab through a bolt, the main body of the pull wire type displacement sensor 3-2 is fixed with the fixed base 3-1 through a bolt, and the pull wire end is fixed with the fixed top cover 3-7 through a thread.

[0096] The tension sensor and the pull wire type displacement sensor of the rigidity detection device need to be calibrated and verified in accuracy. The full-scale measurement accuracy of the sensor should be within ±5%. When the device is used for detection, the basket bolt of the device is adjusted to keep the device perpendicular to the ground relative to the cab, and there is no shaking and loosening between the structures of the test device. The starting data of the sensor is recorded, then the basket bolt of the device is synchronized, and the pull wire type displacement sensor installed through the selected excitation scheme is used to monitor the displacement of each excitation point of the cab, so that the displacement of each excitation point is the same, thereby ensuring that the floor beam and the balance bar of the cab can keep parallel to the ground during displacement. The test data of the tension sensor is recorded every time the cab moves down by a fixed distance until it reaches the limit block.

[0097] The above specific embodiments further illustrate the purpose, technical solutions and advantages of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the protection scope of the present application. It should be particularly pointed out that any modification, equivalent replacement, improvement, etc. made by those skilled in the art within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A cab suspension stiffness detection method characterized by, The application is suitable for a rigidity detection system, wherein the rigidity detection system comprises a cab suspension mechanism and a plurality of rigidity detection devices which are fixed and connected according to a preset excitation scheme; the preset excitation scheme comprises an isosceles triangle three-point excitation scheme and a symmetric four-point excitation scheme; the isosceles triangle three-point excitation scheme is that two excitation points are arranged at the suspension ends of symmetrically distributed rigid structural members or at positions without spatial interference of the installation structure, and the midpoint of the balance bar of the suspension end without symmetrically distributed rigid structural members is selected as a third excitation point, so that the three excitation points form an isosceles triangle; the symmetric four-point excitation scheme is that four excitation points are established at the cab suspension floor beam support and the cab floor beam mounting point, respectively; when the cab suspension mechanism has asymmetric rigid structural members on the left and right sides, or the symmetric rigid structural members of the cab suspension mechanism and the rigidity detection device installation have motion interference, the isosceles triangle three-point excitation scheme is adopted; when the cab suspension mechanism has symmetric rigid structural members on the left and right sides and the symmetric rigid structural members and the rigidity detection device installation have no motion interference, the symmetric four-point excitation scheme is adopted; The cab suspension rigidity detection method comprises the following steps: The horizontal state of the cab suspension mechanism is adjusted, so that the cab suspension mechanism and the ground are kept in a horizontal state; the air bags of the cab suspension mechanism are inflated to increase the pressure of the air bags of the front suspension and the rear suspension, and the pressure is stopped when the air bags rise to the working height of the corresponding vehicle; the air valves of the air bags are adjusted to keep the floor beam and the balance bar of the cab suspension mechanism horizontal; The plurality of rigidity detection devices are adjusted respectively, so that each rigidity detection device is in a pre-tightening state; the pre-tightening state is that there is no shaking and loosening between the structures of the rigidity detection device; The plurality of rigidity detection devices are controlled to make the cab suspension mechanism connected to the rigidity detection devices move down multiple times, and the distance of each time is the same; each rigidity detection device comprises a displacement sensor and a tension sensor; the displacement sensor and the tension sensor of each rigidity detection device are connected to the cab suspension mechanism through the excitation points obtained by the excitation scheme; The rigidity detection devices are controlled to collect the tension required by the cab suspension mechanism when moving down each time until the cab suspension mechanism reaches a preset position, and the tension data is obtained. According to the tension data and the distance of each time of moving down, the stiffness test result of the cab suspension mechanism is obtained by using the segmented displacement method or the total displacement method; wherein, if the local change trend of the stiffness of the cab suspension mechanism after moving down by a certain distance is studied, the segmented displacement method is used to process the data, and the local change trend of the stiffness of the cab suspension mechanism is obtained; if the overall change trend of the stiffness of the cab suspension mechanism from the static state to the preset position is studied, the total displacement method is used to process the data, and the overall change trend of the stiffness of the cab suspension mechanism is obtained.

2. The cab suspension stiffness detection method of claim 1, wherein The cab suspension mechanism and the plurality of stiffness detection devices according to the preset excitation scheme are specifically comprising: According to the analysis of the structure of the cab suspension mechanism, a corresponding excitation scheme is adopted, and the positions and the number of a plurality of excitation points of the cab suspension mechanism are determined according to the excitation scheme; According to the positions and the number of the plurality of excitation points, a plurality of stiffness detection devices are determined to be connected and fixed with the cab suspension mechanism through the plurality of excitation points.

3. The method of claim 1, wherein The distance of each time of moving down is the same, and the tension required by the cab suspension mechanism at each time of moving down is collected, specifically comprising: The plurality of stiffness detection devices control the distance of each time of moving down of the cab suspension mechanism through the displacement sensor; The descent displacement amount of each excitation point is monitored through the displacement sensor, so that the displacement amount of each excitation point is the same, the horizontal state of the cab suspension mechanism is maintained, and the same displacement amount of the cab suspension mechanism is controlled at each time of moving down; The plurality of stiffness detection devices obtain the tension required by the cab suspension mechanism at each time of moving down through the tension sensor.

4. The method of claim 1-3, wherein The stiffness detection device comprises a fixed base, a height adjusting mechanism, a basket bolt fine adjustment mechanism, a sensor fixing mechanism and a fixed top cover; wherein, the fixed base further comprises a pull-wire displacement sensor; the sensor fixing mechanism further comprises a tension sensor; The fixed base is connected and fixed with the cast iron floor through a bolt, and is used for the fixation of the stiffness detection device; the pull-wire displacement sensor is fixed on the fixed base through a bolt, and is used for controlling the same displacement amount of the cab suspension mechanism connected with the stiffness detection device at each time of moving down; The height adjusting mechanism connects the fixed base and the basket bolt fine adjustment mechanism through a thread, and is used for adjusting the height of the stiffness detection device; The basket bolt fine adjustment mechanism is used for pre-tightening through a basket bolt, i.e. eliminating the matching error between mechanisms, and can control and stabilize the displacement amount of the cab suspension mechanism moving down through the basket bolt; The sensor fixing mechanism is connected with the basket bolt fine adjustment mechanism downward through a thread, and is connected with the fixed top cover upward, and is used for the installation and fixation of the measuring sensor; the tension sensor is connected and fixed with the sensor fixing mechanism and the fixed clamp on the cab suspension mechanism through a thread, and is used for measuring the tension required by the cab suspension mechanism at each time of moving down by the same distance. The fixed top cover is connected and fixed with the cab suspension mechanism floor beam through bolts, and is used for connecting and fixing the rigidity detection device with the cab suspension mechanism.

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