A modal test device and method for electric fan of automobile radiator

Abstract

The present invention provides a method and device for testing the modal state of an electric fan of an automobile radiator, including: installing the fan in a simulated real vehicle installation manner, steadily increasing the fan speed, collecting the three-axis component force curves of each installation point during the continuous change of the speed; extracting the first-order three-axis component force curves of each installation point corresponding to the first-order frequency of the fan speed, synthesizing all the first-order three-axis component force curves into a first-order resultant force curve in a vector synthesis manner; and identifying the frequency values ​​corresponding to the peak points of each force value according to the peaks of the first-order resultant force curve. The present invention simulates the fan being in a real vehicle installation manner and a real vehicle operation state, and tests the modal state of the fan. The test results are highly accurate and highly consistent with the actual vehicle installation results. The fan speed data is set according to the obtained data, which can improve the noise and vibration performance of the fan in the real vehicle.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile accessories, and more specifically, to a modal testing device and method for an automobile radiator electric fan. Background Art

[0002] For the electric fan of the car radiator, the main working frequency overlaps with the natural frequency range of the car steering system, dashboard, seat, etc. When the fan is working, it is easy to resonate with these subsystems or parts, causing noise and vibration in the car, resulting in a bad user experience. Through modal testing, the modal frequency vibration type of the fan can be identified, and the design scheme can be adjusted according to the modal test results to avoid the risk of resonance in advance. However, in the current prior art, this type of test fan is not in the actual vehicle installation state, and the fan is not in the actual vehicle operation state. The installation method and working state of the fan have a great influence on the modal test results, which often causes inaccurate fan modal test results. Summary of the invention

[0003] In view of the technical problems existing in the prior art, the present invention provides a method and a device for modal testing of an electric fan of an automobile radiator, thereby improving the accuracy of the fan vibration test.

[0004] According to a first aspect of the present invention, a method for modal testing of an electric fan of an automobile radiator is provided, comprising:

[0005] Install the fan in a simulated real vehicle installation method, steadily increase the fan speed, and collect the three-axis force component curves of each installation point during the continuous change of speed;

[0006] Extract the first-order three-axis component force curve of each installation point corresponding to the first-order frequency of the fan speed, and synthesize all the first-order three-axis component force curves into a first-order resultant force curve in a vector synthesis manner;

[0007] According to the peak of the first-order resultant force curve, the frequency value corresponding to each force peak point is identified.

[0008] Based on the above technical solution, the present invention can also make the following improvements.

[0009] Furthermore, synthesizing all first-order three-axis component force curves into a first-order resultant force curve in a vector synthesis manner includes:

[0010] Obtain the triaxial force component values ​​corresponding to the same sampling time on the first-order triaxial force component curves of all installation points;

[0011] All x-direction force values ​​of the three-axis force components are synthesized into an x-direction resultant force by vector synthesis, all y-direction force values ​​of the three-axis force components are synthesized into a y-direction resultant force by vector synthesis, and all z-direction force values ​​of the three-axis force components are synthesized into a z-direction resultant force by vector synthesis;

[0012] The x-direction resultant force, the y-direction resultant force and the z-direction resultant force are synthesized into a resultant force value by means of vector synthesis, and the resultant force values ​​at all sampling moments together constitute a first-order resultant force curve.

[0013] Furthermore, all first-order triaxial force curves are synthesized into a first-order resultant force curve in a vector synthesis manner, which is completed by the following formula:

[0014]

[0015] F x =F x1 +F x2 +……+F xn

[0016] F y =F y1 +F y2 +……+F yn

[0017] F z =F z1 +F z2 +……+F zn ,

[0018] Wherein, F is the first-order resultant force value at a certain sampling moment, Fx is the resultant force of all installation points in the x direction at this sampling moment, Fy is the resultant force of all installation points in the y direction at this sampling moment, Fz is the resultant force of all installation points in the z direction at this sampling moment, Fx1, Fx2, …, Fxn are the components of the x direction at each installation point of the fan at this sampling moment, Fy1, Fy2, …, Fyn are the components of the y direction at each installation point of the fan at this sampling moment, Fz1, Fz2, …, Fzn are the components of the z direction at each installation point of the fan at this sampling moment, and n is a natural number greater than 1.

[0019] According to a second aspect of the present invention, there is provided a modal test device for an automobile radiator electric fan, comprising: a mounting seat, on which are provided a plurality of mounting points simulating the installation of the fan on a real vehicle, the fan being fixedly installed corresponding to each of the mounting points, and a three-axis force sensor being provided between each mounting point and the fan.

[0020] Preferably, it also includes a driving source, which is electrically connected to the fan and can adjust the fan speed.

[0021] Preferably, the driving source comprises a programmable DC regulated power supply, and the programmable DC regulated power supply is connected to a power supply interface of the fan.

[0022] Preferably, the driving source further includes a PWM signal generator, and the PWM signal generator is connected to a speed regulating interface of the fan.

[0023] Preferably, the mounting seat is provided with a plurality of groups of mounting plates parallel to each other, and a plurality of elongated first slide grooves parallel to each other, the first slide grooves are arranged perpendicular to the mounting plates, the mounting plates are installed in the first slide grooves through sliding connectors, and the mounting plates can slide towards or away from each other; the mounting plate is provided with a second slide groove arranged perpendicular to the first slide groove, the second slide groove is provided with a plurality of sliders, and the sliders are slidably connected to the second slide groove; a three-axis force sensor is fixedly provided on the slider, the mounting point is provided on the slider, and when the fan is in the installed state, the fan is pressed against the three-axis force sensor.

[0024] The present invention provides a method and device for modal testing of an automobile radiator electric fan, which simulates the fan being in a real vehicle installation mode and a real vehicle operation state, and tests the fan's modal state. The test results are highly accurate and highly consistent with the actual installation results. The fan's speed data is set according to the obtained data, which can improve the fan's noise and vibration performance in the real vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A flow chart of a modal test method for an automobile radiator electric fan provided by the present invention;

[0026] Figure 2 This is a schematic diagram of the three-axis force component curve of the first installation point in the embodiment;

[0027] Figure 3 is a schematic diagram of a three-axis force component curve of the second installation point in the embodiment;

[0028] Figure 4 is a schematic diagram of a three-axis force component curve of the third mounting point in the embodiment;

[0029] Figure 5 is a schematic diagram of a three-axis force component curve of the fourth mounting point in the embodiment;

[0030] Figure 6 Schematic diagram of the first-order resultant force curve of all installation points in the embodiment;

[0031] Figure 7 is a schematic diagram of a modal frequency curve of a fan in an embodiment;

[0032] Figure 8 A structural schematic diagram of a certain viewing angle of a vehicle radiator electric fan modal test device provided by the present invention;

[0033] Fig. 9 The present invention is a structural schematic diagram of another perspective of a vehicle radiator electric fan modal testing device provided by the present invention.

[0034] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0035] 1. Mounting seat, 101. Mounting plate, 1011. Second slide groove, 1012. Sliding block, 102. First slide groove, 103. Sliding connector, 104. Three-axis force sensor. DETAILED DESCRIPTION

[0036] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0037] Figure 1 A flow chart of a modal test method for an automobile radiator electric fan provided by the present invention is as follows: Figure 1 As shown, the method includes:

[0038] 101. Install the fan in a simulated real vehicle installation method, steadily increase the fan speed, and collect the three-axis force component curves of each installation point during the continuous change of the speed;

[0039] 102. Extract the first-order three-axis component force curve of each installation point corresponding to the first-order frequency of the fan speed, and synthesize all the first-order three-axis component force curves into a first-order resultant force curve in a vector synthesis manner;

[0040] 103. According to the peak of the first-order resultant force curve, identify the frequency value corresponding to each force peak point.

[0041] It is understandable that based on the defects in the background technology, the embodiment of the present invention proposes a modal test method for an automobile radiator electric fan. The three-axis force component data of each installation point when the fan is installed and running in a simulated real vehicle are collected, and the three-axis force component data obtained at the continuous sampling time form a three-axis force component curve. Since the fan speed also changes gradually, the fan speed is used as the horizontal coordinate and the three-axis force component of each installation point is used as the vertical coordinate to obtain the following: Figures 2 to 5 The three-axis force component curves of the four mounting points are shown. Using this three-axis force component curve as the basic data for subsequent calculations will increase the test accuracy.

[0042] The present invention simulates the fan being in a real vehicle installation mode and a real vehicle operation state, and tests the mode of the fan. The test result is highly accurate and highly consistent with the actual installation result. The fan speed data is set according to the obtained data, which can improve the noise and vibration performance of the fan in the real vehicle.

[0043] It is understandable that the number of mounting points can be flexibly changed according to the difference of fans and installation environments. In order to facilitate a more intuitive description of the present invention, this embodiment is illustrated by four mounting points, that is, assuming that the fan of this embodiment is installed through four mounting points, force values ​​are sampled at the four mounting points respectively, and a force value curve of each mounting point is obtained.

[0044] In a possible embodiment, synthesizing all first-order three-axis component force curves into a first-order resultant force curve in a vector synthesis manner includes:

[0045] Obtain the triaxial force component values ​​corresponding to the same sampling time on the first-order triaxial force component curves of all installation points;

[0046] All x-direction force components of the three-axis force components are synthesized into the x-direction resultant force of all installation points by vector synthesis, all y-direction force components of the three-axis force components are synthesized into the y-direction resultant force of all installation points by vector synthesis, and all z-direction force components of the three-axis force components are synthesized into the z-direction resultant force of all installation points by vector synthesis;

[0047] The x-direction resultant force, the y-direction resultant force and the z-direction resultant force are synthesized into a resultant force value by means of vector synthesis, and the resultant force values ​​at all sampling moments together constitute a first-order resultant force curve.

[0048] In this embodiment, Figures 2 to 5 The figure shows the curve of the three-axis force values ​​of the four installation points obtained by sampling and the change of the fan speed. Figures 2 to 5 The horizontal axis in the middle is the fan speed. As time goes by, the fan speed gradually increases. During the process of increasing the speed, the three-axis force component values ​​collected at each installation point of the fan also change synchronously. Since the present invention aims to analyze the modal of the fan, Figure 6 As shown, this embodiment analyzes the vibration characteristics of the fan by combining the three-axis force values ​​of all installation points into a total resultant force value.

[0049] In a possible implementation manner, all first-order three-axis component force curves are synthesized into a first-order resultant force curve in a vector synthesis manner, which is completed by the following formula:

[0050]

[0051] F x =F x1 +F x2 +……+F xn

[0052] F y =F y1 +F y2 +……+F yn

[0053] F z =F z1 +F z2 +……+F zn ,

[0054] Wherein, F is the first-order resultant force value at a certain sampling moment, Fx is the resultant force of all installation points in the x direction at this sampling moment, Fy is the resultant force of all installation points in the y direction at this sampling moment, Fz is the resultant force of all installation points in the z direction at this sampling moment, Fx1, Fx2, …, Fxn are the components of the x direction at each installation point of the fan at this sampling moment, Fy1, Fy2, …, Fyn are the components of the y direction at each installation point of the fan at this sampling moment, Fz1, Fz2, …, Fzn are the components of the z direction at each installation point of the fan at this sampling moment, and n is a natural number greater than 1.

[0055] It is understandable that this embodiment uses four installation points as an example, so the value of n is 4. The force values ​​in the x-direction, y-direction, and z-direction are synthesized in sequence through the vector synthesis formula, and then the resultant force in the x-direction, the resultant force in the y-direction, and the resultant force in the z-direction are synthesized into a total force value, which is used to determine the total force value of the fan at all installation points. The total force value curve can reflect the vibration conditions of the fan at different speeds. Figure 7 The figure shows the schematic diagram of the fan modal frequency converted from the synthesized first-order resultant force curve. Figure 7 It can be found that the larger the total force value (i.e. the peak value of the force wave), the more intense the vibration. Therefore, based on this modal frequency graph, it can be found at which speed values ​​the fan vibrates more violently. When designing a car fan, avoid the speed value corresponding to the peak value of the force wave on the modal frequency when setting the fan parameters, which can improve the noise and vibration performance of the fan in the actual car and enhance the user experience of the car.

[0056] Figures 8-9 The structure diagram of a vehicle radiator electric fan modal test device provided by the embodiment of the present invention from two different perspectives is as follows: Figures 8-9 As shown, a modal test device for an automobile radiator electric fan comprises: a mounting base 1, on which are provided a plurality of mounting points a for simulating the installation of the fan on a real vehicle, the fan is fixedly installed corresponding to each of the mounting points a, and a three-axis force sensor 104 is provided between each mounting point a and the fan.

[0057] It can be understood that the mounting base 1 is used to simulate the state of the fan being installed in a real vehicle and the use of the fan in the running state of the real vehicle. The fan is installed on the mounting base 1 through various mounting points a, and a three-axis force sensor 104 is set at each mounting point a to collect the three-axis force component data of each mounting point. The three-axis force component data obtained at the continuous sampling time form a three-axis force component curve. Since the fan speed also changes gradually, the fan speed is used as the horizontal coordinate and the three-axis force component of each mounting point is used as the vertical coordinate to obtain the following: Figures 2 to 5 The triaxial force curves of the four mounting points are shown.

[0058] As one of the preferred embodiments, the device also includes a driving source, which is electrically connected to the fan. The driving source can provide power to the fan and adjust the fan speed to complete the test of the solution of the present invention.

[0059] As one of the preferred embodiments, the driving source includes a programmable DC regulated power supply (30V-200A), and the programmable DC regulated power supply is connected to the power interface of the fan. If the fan motor under test is a brushed motor, the output voltage of the regulated power supply can be directly adjusted to gradually increase the speed of the fan from a low speed.

[0060] As one of the preferred embodiments, for the fan under test whose motor adopts a brushless motor, the driving source also includes a PWM signal generator, and the PWM signal generator is connected to the speed control interface of the fan. The fan under test is powered by a programmable DC regulated power supply, and the speed of the fan is adjusted by adjusting the duty cycle of the PWM signal output by the PWM signal generator, so that the speed of the fan increases steadily.

[0061] As one of the preferred embodiments, the mounting seat is provided with a plurality of mutually parallel groups of mounting plates 101 and a plurality of mutually parallel elongated first slide grooves 102, the first slide grooves 102 are arranged perpendicular to the mounting plate 101, the mounting plate 101 is installed in the first slide grooves 102 through a sliding connection 103, and the plurality of mounting plates 101 can slide towards or away from each other; the mounting plate 101 is provided with a second slide groove 1011 arranged perpendicular to the first slide groove 102, the second slide groove 1011 is provided with a plurality of sliders 1012, and the sliders 1012 are slidably connected to the second slide groove 1011; a three-axis force sensor 104 is fixedly provided on the slider 1012, the mounting point a is provided on the slider 1012, and when the fan is in the installed state, the fan is pressed against the three-axis force sensor 104.

[0062] It can be understood that, by vertically setting the first slide groove 102 and the second slide groove 1011, the relative positions of each mounting point a and the number of mounting points a used can be adjusted, thereby increasing the applicable scope of the mounting base 1, making the device of this embodiment suitable for testing fans of more types and sizes.

[0063] It can be understood that the automobile radiator electric fan modal test device provided by the present invention corresponds to the automobile radiator electric fan modal test method provided by the aforementioned embodiments, and the relevant technical features of the automobile radiator electric fan modal test device can refer to the relevant technical features of the automobile radiator electric fan modal test method, which will not be repeated here.

[0064] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0065] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A modal test method for an automobile radiator electric fan, characterized in that: Applied to a vehicle radiator electric fan modal test device, where: The test device comprises a mounting seat, the mounting seat is provided with a plurality of mounting points simulating the installation of a fan on a real vehicle, the fans are fixedly installed corresponding to the respective mounting points, and a three-axis force sensor is provided between each mounting point and the fan; the mounting seat is provided with a plurality of mutually parallel mounting plates and a plurality of mutually parallel long first slide grooves, the first slide grooves are arranged perpendicular to the mounting plates, the mounting plates are installed in the first slide grooves through sliding connectors, and the mounting plates can slide in opposite directions or back to back; the mounting plate is provided with a second slide groove arranged perpendicular to the first slide groove, the second slide groove is provided with a plurality of sliders, and the sliders are slidably connected with the second slide groove; the slider is fixedly provided with a three-axis force sensor, the mounting point is arranged on the slider, and when the fan is in the installed state, the fan is pressed against the three-axis force sensor; Test methods include: Install the fan in a simulated real vehicle installation method, steadily increase the fan speed, and collect the three-axis force component curves of each installation point during the continuous change of speed; Extract the first-order three-axis component force curves of each installation point corresponding to the first-order frequency of the fan speed, and synthesize all the first-order three-axis component force curves into a first-order resultant force curve in a vector synthesis manner; specifically including: Obtain the triaxial force component values ​​corresponding to the same sampling time on the first-order triaxial force component curves of all installation points; All x-direction force values ​​of the three-axis force components are synthesized into an x-direction resultant force by vector synthesis, all y-direction force values ​​of the three-axis force components are synthesized into a y-direction resultant force by vector synthesis, and all z-direction force values ​​of the three-axis force components are synthesized into a z-direction resultant force by vector synthesis; The x-direction resultant force, the y-direction resultant force and the z-direction resultant force at the same sampling moment are synthesized into a resultant force value by vector synthesis, and the resultant force values ​​at all sampling moments together form a first-order resultant force curve; According to the peak of the first-order resultant force curve, the frequency value corresponding to each force peak point is identified.

2. A vehicle radiator electric fan modal testing method according to claim 1, characterized in that: All first-order triaxial force curves are synthesized into a first-order resultant force curve in a vector synthesis manner, which is completed by the following formula: ， Wherein, F is the first-order resultant force value at a certain sampling moment, Fx is the resultant force of all installation points in the x direction at this sampling moment, Fy is the resultant force of all installation points in the y direction at this sampling moment, Fz is the resultant force of all installation points in the z direction at this sampling moment, Fx1, Fx2, …, Fxn are the components of the x direction at each installation point of the fan at this sampling moment, Fy1, Fy2, …, Fyn are the components of the y direction at each installation point of the fan at this sampling moment, Fz1, Fz2, …, Fzn are the components of the z direction at each installation point of the fan at this sampling moment, and n is a natural number greater than 1.

3. A vehicle radiator electric fan modal testing method according to any one of claims 1 to 2, characterized in that: The device also includes a driving source, which is electrically connected to the fan and can adjust the speed of the fan.

4. A vehicle radiator electric fan modal testing method according to claim 3, characterized in that: The driving source comprises a programmable DC regulated power supply, and the programmable DC regulated power supply is connected to a power supply interface of the fan.

5. A vehicle radiator electric fan modal testing method according to claim 4, characterized in that: The driving source also includes a PWM signal generator, and the PWM signal generator is connected to the speed regulating interface of the fan.

Images