Testing device and method for dynamic pressure distribution test of boneless windscreen wiper of automobile

Abstract

The invention discloses a testing device and method for dynamic pressure distribution testing of an automobile boneless windscreen wiper, and relates to the technical field of automobile windscreen wipers. Comprising an overall test bench frame, a rotatable nozzle, a pressure measuring unit, a windshield assembly, a wiper arm, a driving motor and a multi-channel pressure data acquisition module. The rotatable nozzle, the windshield assembly and the driving motor are installed on the overall test bench frame. The wiper arm is mounted on the driving motor, and the boneless wiper to be tested is mounted on the wiper arm; the pressure measuring units are embedded in the windshield assembly, and the multiple pressure measuring units are evenly arranged and electrically connected with the multi-channel pressure data acquisition module. Through the design of the pressure measuring unit and the windshield assembly, the boneless windscreen wiper and the curved flexible film pressure sensor are in full contact, the working mode and the contact mode of the boneless windscreen wiper and the curved flexible film pressure sensor are not changed, and the dynamic pressure distribution condition of the boneless windscreen wiper in the working process can be accurately measured.

Description

Technical Field

[0001] The invention relates to the technical field of automobile windshield wipers, and in particular to a test device and method for testing dynamic pressure distribution of an automobile boneless windshield wiper. Background Art

[0002] Car wipers are one of the important safety components that are indispensable to cars. Their main function is to keep the windshield clean through the reciprocating motion of the wipers in rainy, snowy or other situations where it is necessary to remove moisture, snow, dirt, etc. from the windshield, so as to ensure that the driver has a clear view. Boneless wipers have a simple structure, light weight, and uniform force. Compared with traditional bone wipers, they have better cleaning effects, and because of their more uniform pressure distribution, they reduce wear, reduce noise, and improve durability. With the continuous development of technology, driving safety has received great attention. Car wipers should be strictly controlled from design and production to factory inspection to ensure the high quality and high reliability of car wipers, especially in the design stage and product verification stage. Among them, the pressure distribution test (dynamic / static) of boneless wipers is particularly critical. The test results directly determine the rationality of the wiper structure and its wiper cleanliness.

[0003] At present, the vast majority of wiper design and production companies use non-professional testing equipment and methods to conduct pressure tests, which causes deviations in test results and affects product quality. Even a small number of companies have not conducted analysis and research on the uniformity of pressure distribution on wipers, and only rely on the naked eye to judge the clarity of the windshield and conduct fatigue tests to determine whether the wipers can meet the factory conditions. If professional pressure distribution test equipment and methods are used to conduct pressure distribution tests (dynamic / static) on bone wipers, and the test data and results are combined to optimize the wiper structure, so that the pressure distribution on the contact surface between the wiper and the windshield is more uniform, the wiping effect and service life of the wipers can be significantly improved, and the product quality and brand influence can be greatly improved.

[0004] The Chinese patent application number 201810004897.3 discloses a windshield wiper boneless spring pressure distribution test system and test method. The windshield wiper boneless spring pressure distribution test system analyzes the pressure distribution of the windshield wiper boneless spring positively pressed on the multi-point telescopic rod (simulating the curvature of the glass) under static conditions. But obviously, in addition to the positive pressure perpendicular to the contact surface, the wiper spring should also consider the transmission of the force generated by the deformation of the rubber strip, as well as the friction between the rubber strip and the glass during the dynamic reciprocating motion of the wiper.

[0005] The Chinese patent application number 201710762158.6 discloses a new type of windshield wiper pressure distribution test equipment, which measures the pressure distribution data in both static and relative motion states by contacting the wiper blade with the sensor blade on the test reference plate. It ignores the fact that the friction between the wiper rubber strip and the car glass will also affect the pressure on the wiper surface. Therefore, the wiping effect of the wiper on the sensor blade is completely different from that on the windshield, and there is a significant difference in the drag coefficient, and the working conditions cannot be changed for the convenience of measurement.

[0006] Therefore, the currently disclosed test device for testing the pressure distribution of boneless wipers has the following defects and deficiencies: the pressure distribution of the boneless wiper reed is directly assumed to be the pressure distribution at the contact position between the wiper and the glass; the pressure change caused by the friction with the glass is ignored in the dynamic / static test; and the pressure distribution test of the wiper in a water environment cannot be performed. The above problems all lead to inaccurate measurement results and large measurement errors. Summary of the invention

[0007] The purpose of the present invention is to provide a test device and method that can accurately measure the dynamic pressure distribution of a boneless wiper in view of the problems existing in the existing test device and method for testing the dynamic pressure distribution of a boneless wiper. The wiper makes a reciprocating motion of scraping rain on the glass surface, and the pressure measuring unit embedded in the windshield can measure the single-point pressure at a fixed position. Through the single-point pressure measurement at multiple positions, the dynamic pressure distribution measurement data of the wiper is obtained, and the measurement values ​​of multiple groups of pressure measurement units can be displayed in real time in the computer software. This method makes the test operation simpler, the working conditions more realistic, and the collected data more accurate. At the same time, the dynamic pressure collection software facilitates the processing and analysis of test data, so that the problem of uneven pressure distribution of the wiper can be quantitatively pointed out during the wiper design process.

[0008] To achieve the above-mentioned purpose, the present invention provides a test device for testing the dynamic pressure distribution of a car boneless wiper, comprising an overall test bench frame, a rotatable nozzle, a pressure measuring unit, a windshield assembly, a wiper arm, a drive motor and a multi-channel pressure data acquisition module; the rotatable nozzle, windshield assembly and drive motor are mounted on the overall test bench frame; the rotatable nozzle is located above the windshield assembly and is connected to a water pipe; the wiper arm is mounted on the drive motor, and the boneless wiper to be tested is mounted on the wiper arm and abuts against the windshield assembly; the pressure measuring unit is embedded in the windshield assembly, and a plurality of pressure measuring units are evenly arranged, and the plurality of pressure measuring units are electrically connected to the multi-channel pressure data acquisition module.

[0009] Furthermore, the overall test bench frame includes a base frame, a large upright frame, a small upright frame and a windshield fixing frame; the large upright frame, the small upright frame and the windshield fixing frame are all fixedly connected to the base frame; the windshield assembly is installed on the windshield fixing frame; the rotatable nozzle is installed at the bottom of the upper beam of the large upright frame; and the drive motor is installed on the small upright frame.

[0010] Furthermore, the windshield fixing frame includes an oblique frame and a base support frame, the base support frame is parallel to the small upright frame and is located behind the small upright frame, and the angle between the oblique frame and the large upright frame is set to α, which depends on the specific model of the vehicle.

[0011] Furthermore, two rotatable spray heads are provided and symmetrically arranged at the bottom of the upper beam of the large upright frame.

[0012] Furthermore, the pressure measuring unit includes a fixed block and a curved flexible film pressure sensor arranged on the top of the fixed block, and a layer of waterproof paint is coated on the surface of the curved flexible film pressure sensor.

[0013] Furthermore, the windshield assembly includes a windshield and a pad, the curvature of the windshield assembly is consistent with the curvature of the front windshield of the actual vehicle, and the curvature and size of the upper surface of the pad are completely consistent with the bottom surface of the windshield; the windshield is provided with a plurality of through holes corresponding one-to-one to the pressure measuring units, and the pad is provided with a plurality of mounting grooves corresponding one-to-one to the pressure measuring units.

[0014] Furthermore, the multi-channel pressure data acquisition module includes a multi-channel data acquisition device and a PC; the plurality of pressure measurement units are electrically connected to the multi-channel data acquisition device, and the multi-channel data acquisition device is electrically connected to the PC.

[0015] The present invention also provides a test method for testing the dynamic pressure distribution of a car's frameless windshield wiper, comprising the following steps:

[0016] S1. Prepare the frameless wiper to be tested according to the test requirements and record the model and size parameters of the frameless wiper to be tested;

[0017] S2. Preparation of the test device: install the boneless wiper to be tested on the wiper arm and set the clamping stress of the initial static condition, turn on the multi-channel pressure data acquisition module, and adjust the rotatable nozzle to spray water;

[0018] S3, start the test, turn on the drive motor, adjust the swing speed of the wiper arm, and display and record the test data in real time through the multi-channel pressure data acquisition module;

[0019] S4, end the test, store the test measurement data, and turn off the drive motor and the rotatable nozzle;

[0020] S5. Organize the test data and conduct test data analysis.

[0021] The present invention has the following beneficial effects:

[0022] 1. The present invention, through the design of the pressure measurement unit and the windshield assembly, makes the boneless wiper and the curved flexible film pressure sensor fully contact without changing their working mode and contact mode, and can accurately measure the dynamic pressure distribution of the boneless wiper during its working process, which is convenient for analyzing the dynamic pressure distribution of the boneless wiper and timely proposing the optimal design scheme of the boneless wiper. The design of the pressure measurement unit and the windshield assembly simplifies the test process, improves the test efficiency, and reduces the test cost of the boneless wiper.

[0023] 2. The test device and method of the present invention can obtain dynamic pressure distribution data of the boneless wiper at different windshield positions under different rainfall conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The present invention is an overall schematic diagram of a test device for testing the dynamic pressure distribution of a vehicle's frameless wiper.

[0025] Figure 2 This is a schematic diagram of the installation distribution of the pressure measuring unit of a test device for testing the dynamic pressure distribution of a frameless wiper of an automobile on a pad.

[0026] Figure 3 The present invention is a schematic diagram of a pad of a test device for testing the dynamic pressure distribution of a frameless windshield wiper of an automobile.

[0027] Figure 4 The present invention is a schematic diagram of the installation method of a single pressure measurement unit and a pad of a test device for testing the dynamic pressure distribution of a vehicle's frameless wiper.

[0028] Figure 5 The present invention is a schematic diagram of a pressure measuring unit of a test device for testing the dynamic pressure distribution of a vehicle's boneless windshield wiper.

[0029] Figure 6 A windshield schematic diagram of a test device for testing dynamic pressure distribution of a vehicle's frameless wiper according to the present invention.

[0030] Among them, 1- overall test bench frame; 2- pressure measurement unit; 3- windshield assembly; 4- wiper arm; 5- multi-channel pressure data acquisition module; 11- base frame; 12- large upright frame; 13- small upright frame; 14- windshield fixing frame; 15- rotatable nozzle; 21- fixed block; 22- curved flexible film pressure sensor; 31- windshield; 32- pad; 41- boneless wiper to be tested; 51- multi-channel data collector; 52- PC. DETAILED DESCRIPTION

[0031] In order to achieve the above-mentioned purpose and effect, the technical means and structures adopted by the present invention are described in detail with reference to the accompanying drawings for the features and functions of the preferred embodiments of the present invention.

[0032] like Figure 1-6 As shown, the present invention provides a test device for dynamic pressure distribution test of automobile boneless wipers, comprising an overall test bench frame 1, a rotatable nozzle 15, a pressure measuring unit 2, a windshield assembly 3, a wiper arm 4, a drive motor and a multi-channel pressure data acquisition module 5; the rotatable nozzle 15, the windshield assembly 3 and the drive motor are installed on the overall test bench frame 1; the rotatable nozzle 15 is located above the windshield assembly 3 and is connected to the tap water pipe; the wiper arm 4 is installed on the drive motor, and the boneless wiper 41 to be tested is installed on the wiper arm 4 and abuts against the windshield assembly 3; the pressure measuring unit 2 is embedded in the windshield assembly 3, and a plurality of pressure measuring units 2 are evenly arranged, and the plurality of pressure measuring units 2 are all electrically connected to the multi-channel pressure data acquisition module 5.

[0033] The overall test bench frame 1 includes a base frame 11 , a large upright frame 12 , a small upright frame 13 , a windshield fixing frame 14 , and a rotatable spray head 15 .

[0034] The base frame 11 is provided with a plurality of rectangular drainage grooves, and the accumulated water at the bottom of the test bench is promptly drained during the test in simulated rainy weather. The large upright frame 12, the small upright frame 13 and the windshield fixing frame 14 are all welded and fixed to the base frame 11.

[0035] The windshield assembly 3 is consistent with the actual installation position of the front windshield of the car. The windshield fixing frame 14 includes an inclined frame and a base support frame. The base support frame is parallel to the small upright frame 13, and the parallelism error does not exceed 0.01mm. The angle between the inclined frame and the large upright frame 12 is set to α (α depends on the specific model of the vehicle) to ensure that the installed windshield assembly 3 has the same angle as in the actual situation.

[0036] Two rotatable sprinklers 15 are provided, which are symmetrically arranged at the bottom of the upper beam of the large upright frame 12. The rotatable sprinklers 15 with different outlet apertures can be replaced according to the simulated rainfall amount required.

[0037] The pressure measuring unit 2 includes a fixing block 21 and a curved flexible film pressure sensor 22 .

[0038] The fixing block 21 can be disassembled and replaced by rotating the fixing block 21 according to actual use conditions.

[0039] The surface of the curved flexible film pressure sensor 22 is coated with a layer of waterproof paint to ensure the circuit safety during the test process. The curved flexible film pressure sensor 22 is attached to the surface of the fixing block 21.

[0040] The thickness of the curved flexible film pressure sensor is 0.3mm and the error is ±0.01mm.

[0041] The signal line of the curved flexible film pressure sensor passes through the interior of the fixing block 21 and comes out from the rear of the fixing block 21 .

[0042] The windshield assembly 3 includes a windshield 31 and a backing plate 32 .

[0043] The windshield 31 can be modified from the original vehicle windshield, or a windshield 31 having a curvature consistent with that of the actual vehicle front windshield and a curvature error of the curved surface within the range of ±0.001 can be used.

[0044] The backing plate 32 is a high-precision designed curved surface. The curvature, that is, the shape structure and size of the upper surface of the backing plate 32 and the bottom surface of the windshield 31 are completely consistent, so that the windshield 31 and the backing plate 32 fit completely.

[0045] The windshield 31 is perforated, and a specific groove is provided on the other side of the pad 32 for installation with the fixing block 21. The layout parameters of the through holes are defined, including the number of rows N and the number of columns M, that is, the number and arrangement of the through holes provided on the windshield 31, as well as the width W, height H, thickness T and curvature function C(u) of the windshield. C(u) represents the curvature of the windshield 31, which depends on the horizontal position u. u represents the horizontal parameter, v represents the vertical parameter, and the position of the through hole is described by the parameters (u, v). Assuming that the value range of u is 0≤u≤1 and the value range of v is 0≤v≤1, the horizontal and vertical positions of the through hole x(u, v) and y(u, v) are expressed as x(u, v)=u×W and y(u, v)=v×H+C(u).

[0046] The structural designs of the windshield 31, the backing plate 32 and the fixed block 21 are coordinated with each other. The windshield 31 is punched with 8 rows and 8 columns at equal intervals, that is, N=8, M=8, and then the backing plate 32 is punched with the same curvature as the curvature of the windshield 31 (curvature error ≤±0.001), and the position of the through hole of the backing plate 32 is consistent with the position of the through hole of the windshield 31. The curved flexible film pressure sensor 22 is fixedly installed on the upper surface of the fixed block 21, and the surface of the curved flexible film pressure sensor 22 is waterproofed before installation. The upper surface of the fixed block 21 is kept at a distance of 0.3mm (error ±0.01mm) from the upper surface of the windshield 31 at the location, so that after the fixed block 21 is installed with the curved flexible film pressure sensor 22 with a thickness of 0.3mm, it can ensure that the installed flexible sensing film pressure sensor 22 is consistent with the curvature of the windshield 31 (curvature error ≤±0.001).

[0047] During the installation process, the pressure measuring unit 2 is aligned with the slot hole of the pad 32, and the fixing block 21 is fixed to the pad 32 by rotating 180°. At the same time, the surface curvature of the curved flexible film pressure sensor 22 is consistent with the curvature of the current through-hole position of the windshield 31, so that the boneless wiper 41 to be tested can be in full contact with the windshield 31 and the curved flexible film pressure sensor 22, and wipe normally.

[0048] The frameless wipers 41 to be tested of different models and sizes are installed on the wiper arm 4 through connectors.

[0049] The multi-channel pressure data acquisition module 5 includes a multi-channel data acquisition device 51 and a PC 52 .

[0050] The signal line output by each pressure measuring unit 2 is connected to one of the channels of the multi-channel data collector 51 , and the multi-channel data collector 51 can simultaneously receive 64 groups of piezoelectric signals output by the pressure measuring units 2 .

[0051] The multi-channel data acquisition device 51 is connected to the PC 52 and transmits data. The PC 52 is equipped with a multi-channel boneless wiper dynamic pressure distribution test software. Through the dynamic pressure test software, the pressure value at the location of each pressure measurement unit 2 can be displayed in real time, and then a pressure distribution curve can be generated, which can clearly present the pressure distribution situation.

[0052] The measured data can be saved and downloaded, which is convenient for testers to perform secondary processing.

[0053] The present invention also provides a test method for testing the dynamic pressure distribution of a car's frameless windshield wiper, comprising the following steps:

[0054] S1. Prepare the frameless wiper 41 to be tested according to the test requirements, and record the model, size and other parameters of the frameless wiper 41 to be tested;

[0055] S2, test device preparation work; install the boneless wiper 41 to be tested on the wiper arm 4 and set the clamping stress of the initial static condition, turn on the multi-channel pressure data acquisition module 5, and adjust the rotatable nozzle 15 to spray water;

[0056] S3, start the test, turn on the drive motor, adjust the swing speed of the wiper arm 4, and display and record the test data in real time through the multi-channel pressure data acquisition module 5;

[0057] S4, end the test, store the test measurement data, and turn off the drive motor and the rotatable nozzle 15;

[0058] S5. Organize the test data and conduct test data analysis.

[0059] The above descriptions are only preferred embodiments of the present invention, not all embodiments. Anyone should be aware that any structural changes made under the inspiration of the present invention, and any technical solutions that are the same or similar to the present invention, belong to the protection scope of the present invention.

Claims

1. A test device for testing the dynamic pressure distribution of a car's frameless wiper, characterized in that: It includes an overall test bench frame, a rotatable nozzle, a pressure measuring unit, a windshield assembly, a wiper arm, a drive motor and a multi-channel pressure data acquisition module; the rotatable nozzle, windshield assembly and drive motor are installed on the overall test bench frame; the rotatable nozzle is located above the windshield assembly and is connected to the water pipe; the wiper arm is installed on the drive motor, and the boneless wiper to be tested is installed on the wiper arm and abuts against the windshield assembly; the pressure measuring unit is embedded in the windshield assembly, and a plurality of pressure measuring units are evenly arranged, and the plurality of pressure measuring units are electrically connected to the multi-channel pressure data acquisition module.

2. The test device for testing the dynamic pressure distribution of a car's frameless wiper as claimed in claim 1, characterized in that: The overall test bench frame includes a base frame, a large upright frame, a small upright frame and a windshield fixing frame; the large upright frame, the small upright frame and the windshield fixing frame are all fixedly connected to the base frame; the windshield assembly is installed on the windshield fixing frame; the rotatable nozzle is installed at the bottom of the upper beam of the large upright frame; and the drive motor is installed on the small upright frame.

3. A test device for testing dynamic pressure distribution of a car's frameless wiper as claimed in claim 1 or 2, characterized in that: The windshield fixing frame includes an oblique frame and a base support frame, the base support frame is parallel to the small upright frame and is located behind the small upright frame, and the angle between the oblique frame and the large upright frame is set to α, which depends on the specific model of the vehicle.

4. The test device for testing the dynamic pressure distribution of a car's frameless wiper as claimed in claim 3, characterized in that: There are two rotatable spray heads, which are symmetrically arranged at the bottom of the upper beam of the large upright frame.

5. The test device for testing the dynamic pressure distribution of a car's frameless wiper as claimed in claim 4, characterized in that: The pressure measuring unit comprises a fixed block and a curved flexible film pressure sensor arranged on the top of the fixed block, and a layer of waterproof paint is coated on the surface of the curved flexible film pressure sensor.

6. The test device for testing the dynamic pressure distribution of a car's frameless wiper as claimed in claim 5, characterized in that: The windshield assembly includes a windshield and a pad. The curvature of the windshield assembly is consistent with the curvature of the front windshield of an actual vehicle. The curvature and size of the upper surface of the pad are completely consistent with those of the bottom surface of the windshield. The windshield is provided with a plurality of through holes corresponding to the pressure measuring units one by one, and the pad is provided with a plurality of mounting grooves corresponding to the pressure measuring units one by one.

7. A test device for testing dynamic pressure distribution of a car's frameless wiper as claimed in claim 5 or 6, characterized in that: The multi-channel pressure data acquisition module includes a multi-channel data acquisition device and a PC; a plurality of pressure measurement units are electrically connected to the multi-channel data acquisition device, and the multi-channel data acquisition device is electrically connected to the PC.

8. A test method for dynamic pressure distribution test of a car's frameless wiper, characterized in that: The test device for testing the dynamic pressure distribution of a vehicle windshield wiper as claimed in any one of claims 1 to 7 comprises the following steps: S1. Prepare the frameless wiper to be tested according to the test requirements and record the model and size parameters of the frameless wiper to be tested; S2. Preparation of the test device: install the boneless wiper to be tested on the wiper arm and set the clamping stress of the initial static condition, turn on the multi-channel pressure data acquisition module, and adjust the rotatable nozzle to spray water; S3, start the test, turn on the drive motor, adjust the swing speed of the wiper arm, and display and record the test data in real time through the multi-channel pressure data acquisition module; S4, end the test, store the test measurement data, and turn off the drive motor and the rotatable nozzle; S5. Organize the test data and conduct test data analysis.

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