Small-capacity automotive interior collision impact equipment and impact test methods

Abstract

This invention discloses a low-energy automotive interior collision impact device and impact testing method. The low-energy automotive interior collision impact device includes a base and a gantry frame mounted on the base. A tooling fixture is installed on the base, and a sleeve guide rail is vertically mounted above the base. A drop hammer is arranged inside the sleeve guide rail, and an electromagnetic chuck is positioned at the top of the drop hammer. The electromagnetic chuck controls the magnetic force by discharging a coil, thus controlling the attraction and release of the drop hammer. The top of the electromagnetic chuck is connected via a steel wire rope to a motor mounted on a crossbeam of the gantry frame. A laser rangefinder sensor is positioned on one side of the motor, and a safety pin is provided as a safety device to prevent accidental failure of the electromagnetic chuck. This invention provides a testing method for drop tests of vehicle components such as headlights, door interior panels, dashboards, and high-voltage wiring harnesses, and provides a testing platform for low-energy, high-precision longitudinal dynamic impact tests on automotive parts.

Description

Technical Field

[0001] This invention relates to the field of automotive component collision impact testing equipment, and in particular to a low-energy automotive interior collision impact device and impact testing method. Background Technology

[0002] Impact testing is a common method for testing the performance of automotive components, effectively simulating the performance of vehicle parts under impact from external objects. The working principle typically involves raising a drop hammer to a specific height in a certain way, then releasing it, ultimately impacting the test sample at a certain velocity. Different impact energies are achieved by changing the mass of the drop hammer or the height at which it is raised.

[0003] Existing impact testing equipment typically delivers impact energies ranging from a few hundred to a few thousand joules, which is insufficient for testing small automotive components such as headlights, door panels, dashboards, and high-voltage wiring harnesses. Furthermore, energy loss is common during impacts due to mechanical friction and air resistance. Current impact testing methods often neglect this energy loss, which is not insignificant and can lead to inaccurate results.

[0004] With the rapid development of the automotive parts industry and the booming rise of the new energy vehicle industry, product quality requirements are becoming increasingly stringent, and the demand for testing accuracy is also rising, necessitating more precise testing solutions. Therefore, developing new testing equipment to conduct tests and inspections to ensure the safe use of various components is of great significance in order to meet these increasingly stringent testing requirements. Summary of the Invention

[0005] The purpose of this invention is to address the technical deficiencies in the existing technology by providing a low-energy (less than or equal to 100 joules) automotive interior collision impact device and impact testing method for automotive interior impact conditions, which can provide a testing platform for low-energy, high-precision longitudinal dynamic impact at the automotive component level.

[0006] In one aspect, the present invention provides a low-energy automotive interior collision impact device, comprising a base and a gantry frame arranged on the upper surface of the base. A tooling fixture is provided on the base, and a sleeve guide rail is vertically arranged above the base. A drop hammer is arranged within the sleeve guide rail, and an electromagnetic chuck is arranged at the top of the drop hammer. The electromagnetic chuck controls the magnetic force by discharging a coil, thereby controlling the attraction and release of the drop hammer. The top of the electromagnetic chuck is connected via a steel wire rope to a motor arranged on the crossbeam of the gantry frame. A laser rangefinder sensor is arranged on one side of the motor to measure the distance between the laser rangefinder sensor and the drop hammer. A safety pin is provided as a safety device to prevent accidental failure of the electromagnetic chuck.

[0007] The top and bottom ends of the sleeve guide rail are connected and fixed to the guide rail fixing device, which is arranged inside the column of the gantry frame.

[0008] The drop hammer consists of two parts: a hammer body and a hammer head. The hammer body is located at the top of the hammer head and has a safety through hole arranged in the radial direction. Its upper end is used to connect and cooperate with the electromagnetic chuck.

[0009] When performing the safety function, the safety pin passes radially through the sleeve guide rail and is installed in the safety through hole of the hammer body of the drop hammer.

[0010] The base is equipped with leveling feet at its bottom to achieve leveling.

[0011] In another aspect, the present invention provides a method for conducting a low-energy vehicle interior collision impact test, using the aforementioned low-energy vehicle interior collision impact device, and comprising the following steps during the impact test:

[0012] Step 1: Install the test hammer head to assemble the drop hammer;

[0013] Step 2: Install the safety pin in the safety through hole of the drop hammer;

[0014] Step 3: Install the sample to be tested and its corresponding tooling fixtures on the base;

[0015] Step 4: Remove the safety pin;

[0016] Step 5: Control the motor to adjust the position of the drop hammer by pulling the steel wire rope and the electromagnetic chuck until it contacts the sample to be tested and its corresponding tooling fixture.

[0017] Step 6: Set the laser rangefinder sensor reading to zero, and use the position after zeroing as the height 0;

[0018] Step 7: Based on the pre-calculated drop height H, raise the drop hammer to the designated height;

[0019] Step 8: The electromagnetic chuck is released, and the drop hammer falls along the sleeve guide rail, impacting the sample to be tested and its corresponding tooling fixture.

[0020] The falling height H is calculated in advance using the following formula:

[0021] H = {W1 + W2 + W3 + E} / {(M + m)g}

[0022] In the formula, Work done for frictional resistance, To do work for the electromagnetic chuck, Work done by air resistance, H0 is the falling height when the hammer is completely separated from the electromagnetic chuck, E is the impact energy of the hammer head; M is the mass of the hammer head, m is the mass of the hammer body, g is the acceleration due to gravity, F is the electromagnetic chuck resistance of the falling hammer, f is the frictional resistance of the falling hammer, f(H) represents the falling height as a function of frictional resistance, F(H) represents the falling height as a function of electromagnetic chuck resistance, and cV(H) represents the falling height as a function of damping coefficient c and contact velocity V.

[0023] The impact energy E is represented by the following equation:

[0024] E = 0.5(M + m)V 2 ,

[0025] (M+m)gH-W1-W2-W3=0.5(M+m)V 2 .

[0026] Wherein, cV(H), f(H) and F(H) are calculated after pre-testing, and the processing steps include:

[0027] Define the falling height H as a continuous function of time t during the hammer's descent, expressed as H(t). The falling height H changes continuously with time t, while discrete data is expressed as H(t). i With H i+1 ;

[0028] At the moment of impact, the falling hammer exhibits the following dynamic equation:

[0029] (M+m)gF i -f i =(M+m)a i (1)

[0030] In the formula, a is the impact acceleration of the falling hammer, and i is a subscript indicating that at time i, a i F represents the impact acceleration of the falling hammer at time i. i f represents the resistance of the electromagnetic chuck as the hammer falls at time i. i This represents the frictional resistance of the falling hammer at time i.

[0031] Once the drop hammer has completely separated from the electromagnetic chuck, the dynamic equation of the drop hammer is as follows:

[0032] (M+m)gf i -c i V i =(M+m)a i (2)

[0033] (M+m)gf i+1 -c i+1 V i+1=(M+m)a i+1 (3)

[0034] In the formula, c i V is the damping coefficient of the falling hammer at time i. i Let f be the contact velocity of the falling hammer at time i. i+1 c i+1 V i+1 These represent the frictional resistance, damping coefficient, and contact velocity of the falling hammer at time i+1, respectively.

[0035] When H i and H i+1 When approaching infinitely, the approximate value of c is... i =c i+1 and f i =f i+1 Solve the following system of equations to get c i f i :

[0036] c i =c i+1 =(M+m)(a i -a i+1 ) / (V i+1 -V i (4)

[0037] f i =f i+1 =(M+m){ga i -V i (a i -a i+1 ) / (V i+1 -V i (5)

[0038] Substituting equation (5) into equation (1), we can solve the equation to obtain F. i =:

[0039] F i = (M+m)V i (a i -a i+1 ) / (V i+1 -V i (6)

[0040] During the test, the sampling frequency of the data acquisition device was set to 10000Hz, with a time interval of 0.0001s. Every 0.0001s, the data acquisition device recorded and output an acceleration, which, after integration, output a velocity and a drop height. Substituting the velocity and drop height data into equations (4), (5), and (6) respectively, multiple sets of c values ​​were obtained. i f i and Fi cV(H), f(H), and F(H) are obtained through data statistics.

[0041] The invention relates to a low-energy automotive interior collision impact device technology, which can provide a test method for drop tests of vehicle components such as headlights, door interior panels, dashboards, and high-voltage wiring harnesses, and provide a test platform for low-energy, high-precision longitudinal dynamic impacts on automotive parts. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of the low-energy automotive interior collision impact device according to an embodiment of the present invention. Detailed Implementation

[0043] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0044] like Figure 1 As shown, the low-energy (less than or equal to 100 joules) automotive interior collision impact device of this invention includes a base 1 and a gantry frame 2 arranged on the upper surface of the base 2. A tooling fixture 6 is provided on the base. A sleeve guide rail 7 is vertically arranged above the base 1. A drop hammer 8 is arranged inside the sleeve guide rail 7. An electromagnetic chuck 10 is arranged at the top of the drop hammer 8. The electromagnetic chuck 10 uses electromagnetic principles to control the magnetic force by discharging a coil, thereby completing the adsorption and release control of the drop hammer 8. The top of the electromagnetic chuck 10 is connected to a motor 12 through a steel wire rope 11. The motor 12 is arranged on the bottom surface of the crossbeam of the gantry frame 2. A laser rangefinder 4 is arranged on one side of the motor 12 to measure the distance between the laser rangefinder 4 and the drop hammer 8.

[0045] In some embodiments, the top and bottom ends of the sleeve guide rail 7 are connected and fixed to the guide rail fixing device 3. The guide rail fixing device is arranged inside the column of the gantry frame. Preferably, the sleeve guide rail 7 adopts a partial constraint design, that is, the material is removed spirally on the cylinder to effectively reduce the influence of mechanical friction resistance on the falling energy. The partial sleeve guide rail is used to replace the through groove, thereby reducing the influence of the guide rail on the impact energy.

[0046] In some embodiments, the base 1 is provided with leveling feet 5 at its bottom to achieve leveling of the base 1. The base 1 can be a steel plate with sufficient mass and rigidity. Four leveling feet 5 are evenly installed below it to ensure that the entire device can be level on any ground surface. The sample to be tested and its corresponding tooling fixtures 6 are placed on top of it.

[0047] In this embodiment of the invention, the laser rangefinder 4 is arranged on the bottom surface of the crossbeam of the gantry 2. The laser sensor 4 can be zeroed at any height of the drop hammer 8. When the drop hammer 8 rises, that is, approaches the laser rangefinder 4, the distance is a positive value, and vice versa.

[0048] In some embodiments, the falling hammer 8 consists of two parts: a hammer body and a hammer head. The hammer head may have a hemispherical bottom surface, such as... Figure 1 As shown. It can also be replaced according to different test requirements, including but not limited to mass, shape, etc. The hammer body is a small-diameter rod that cooperates with the electromagnetic chuck 10 and adopts a flexible and variable connection interface. The hammer body can be connected with different hammer heads. The hammer heads can be replaced according to different test requirements, thereby changing the shape of the impact hammer head to meet different test requirements and realizing different test inputs such as impact energy.

[0049] Furthermore, in some embodiments, a safety pin 9 is provided. The safety pin 9 passes radially through the sleeve guide rail 7 and is installed in the through hole of the hammer body of the drop hammer 8. The safety pin 9 is an additional safety device to prevent accidental failure of the electromagnetic chuck 10. During the test preparation phase, even if the electromagnetic chuck 10 suddenly loses power, the safety pin 9 can effectively prevent the drop hammer structure 8 from falling off. Once the test is ready, the safety pin 9 can be removed.

[0050] The low-energy automotive interior collision impact device of this invention can provide a test method for drop tests of vehicle components such as headlights, door interior panels, dashboards, and high-voltage wiring harnesses, and provide a test platform for low-energy, high-precision longitudinal dynamic impacts on automotive parts.

[0051] The following steps are used when conducting impact tests with the low-energy automotive interior collision impact device according to an embodiment of the present invention:

[0052] Step 1: Install the test hammer head to assemble the drop hammer;

[0053] Step 2: Install the safety pin in the safety through hole of the drop hammer;

[0054] Step 3: Install the sample to be tested and its corresponding tooling fixtures on the base;

[0055] Step 4: Remove the safety pin;

[0056] Step 5: Control the motor to adjust the position of the drop hammer by pulling the steel wire rope and the electromagnetic chuck until it contacts the sample to be tested and its corresponding tooling fixture.

[0057] Step 6: Set the laser rangefinder sensor reading to zero, and use the position after zeroing as the height 0;

[0058] Step 7: Based on the pre-calculated drop height H, raise the drop hammer to the designated height;

[0059] Step 8: The electromagnetic chuck is released, and the drop hammer falls along the sleeve guide rail, impacting the sample to be tested and its corresponding tooling fixture.

[0060] The falling height H is calculated in advance using the following formula:

[0061] H = {W1 + W2 + W3 + E} / {(M + m)g}

[0062] In the formula, Work done for frictional resistance, To do work for the electromagnetic chuck, Work done by air resistance, H0 is the falling height corresponding to the complete separation of the drop hammer from the electromagnetic chuck, E is the impact energy of the hammer head; M is the mass of the hammer head, m is the mass of the hammer body, g is the acceleration due to gravity, F is the electromagnetic chuck resistance of the falling hammer, f is the frictional resistance of the falling hammer, f(H) represents the falling height as a function of frictional resistance, F(H) represents the falling height as a function of electromagnetic chuck resistance, and cV(H) represents the falling height as a function of damping coefficient c and contact velocity V.

[0063] The impact energy E is represented by the following equation:

[0064] E = 0.5(M + m)V 2 ,

[0065] (M+m)gH-W1-W2-W3=0.5(M+m)V 2 .

[0066] Wherein, cV(H), f(H) and F(H) are calculated after pre-testing, and the processing steps include:

[0067] Define the falling height H as a continuous function of time t during the hammer's descent, expressed as H(t). The falling height H changes continuously with time t, while discrete data is expressed as H(t). i With H i+1 ;

[0068] At the moment of impact, the falling hammer exhibits the following dynamic equation:

[0069] (M+m)gF i -f i =(M+m)a i (1)

[0070] In the formula, a is the impact acceleration of the falling hammer, and i is a subscript indicating that at time i, a i F represents the impact acceleration of the falling hammer at time i. if represents the resistance of the electromagnetic chuck as the hammer falls at time i. i This represents the frictional resistance of the falling hammer at time i.

[0071] Once the drop hammer has completely separated from the electromagnetic chuck, the dynamic equation of the drop hammer is as follows:

[0072] (M+m)gf i -c i V i =(M+m)a i (2)

[0073] (M+m)gf i+1 -c i+1 V i+1 =(M+m)a i+1 (3)

[0074] In the formula, c i V is the damping coefficient of the falling hammer at time i. i Let f be the contact velocity of the falling hammer at time i. i+1 c i+1 V i+1 These represent the frictional resistance, damping coefficient, and contact velocity of the falling hammer at time i+1, respectively.

[0075] When H i and H i+1 When approaching infinitely, the approximate value of c is... i =c i+1 and f i =f i+1 Solve the following system of equations to get c i f i :

[0076] c i =c i+1 =(M+m)(a i -a i+1 ) / (V i+1 -V i (4)

[0077] f i =f i+1 =(M+m){ga i -V i (a i -a i+1 ) / (V i+1 -V i (5)

[0078] Substituting equation (5) into equation (1), we can solve the equation to obtain F. i =:

[0079] Fi = (M+m)V i (a i -a i+1 ) / (V i+1 -V i (6)

[0080] During the test, the sampling frequency of the data acquisition device was set to 10000Hz, with a time interval of 0.0001s. Every 0.0001s, the data acquisition device recorded and output an acceleration, which, after integration, output a velocity and a drop height. Substituting the velocity and drop height data into equations (4), (5), and (6) respectively, multiple sets of c values ​​were obtained. i f i and F i cV(H), f(H), and F(H) are obtained through data statistics.

[0081] The collision impact testing method of the present invention relies solely on the mass of the falling hammer and the release height as the source of impact energy. It has a simple structure, low device development and installation costs, and the parameter extraction method after the test clarifies the influence relationship of suction cup resistance, mechanical friction resistance and air resistance on energy loss, which is beneficial to the precise control of impact energy.

[0082] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention.

[0083] Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of the equivalents of the claims be included within the invention.

[0084] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A low-energy automotive interior collision impact device, characterized in that, The device includes a base and a gantry frame arranged on the upper surface of the base. A tooling fixture is provided on the base. A sleeve guide rail is vertically arranged above the base, and a drop hammer is arranged inside the sleeve guide rail. An electromagnetic chuck is arranged at the top of the drop hammer. The electromagnetic chuck controls the magnetic force by discharging a coil, thus controlling the attraction and release of the drop hammer. The top of the electromagnetic chuck is connected to a motor arranged on the crossbeam of the gantry frame via a steel wire rope. A laser rangefinder is arranged on one side of the motor to measure the distance between the laser rangefinder and the drop hammer. A safety pin is provided as a safety device to prevent accidental failure of the electromagnetic chuck. The impact test follows these steps: Step 1: Install the test hammer head to assemble the drop hammer; Step 2: Install the safety pin in the safety through hole of the drop hammer; Step 3: Install the sample to be tested and its corresponding tooling fixtures on the base; Step 4: Remove the safety pin; Step 5: Control the motor to adjust the position of the drop hammer by pulling the steel wire rope and the electromagnetic chuck until it contacts the sample to be tested and its corresponding tooling fixture. Step 6: Set the laser rangefinder sensor reading to zero, and use the position after zeroing as the height 0; Step 7: Based on the pre-calculated drop height H, raise the drop hammer to the designated height; Step 8: The electromagnetic chuck is released, and the drop hammer falls along the sleeve guide rail, impacting the sample to be tested and its corresponding tooling fixture. The falling height H is pre-calculated using the following formula: H={W1+W2+W3+E} / {(M+m)g}; In the formula, Work done on frictional resistance ， Doing work for the electromagnetic chuck ， Work done by air resistance; H0 is the drop height when the hammer is completely separated from the electromagnetic chuck; E is the impact energy of the hammer head; M is the mass of the hammer head; m is the mass of the hammer body; g is the acceleration due to gravity; F is the resistance of the electromagnetic chuck during the fall of the hammer; f is the frictional resistance during the fall of the hammer. A function representing the falling height and frictional resistance. The function representing the falling height and the resistance of the electromagnetic chuck. Indicates the drop height and damping coefficient Contact speed The function; The , , Calculated after prior testing, the processing steps include: Define the falling height H as a continuous function of time t during the hammer's descent, expressed as H(t). The falling height H changes continuously with time t, while discrete data is expressed as H(t). i With H i+1 ; At the moment of impact, the falling hammer exhibits the following dynamic equation: (M+m)g-F i -f i =(M+m)a i (1) In the formula, a is the impact acceleration of the falling hammer, and i is a subscript indicating that at time i, a i F represents the impact acceleration of the falling hammer at time i. i f represents the resistance of the electromagnetic chuck as the hammer falls at time i. i This represents the frictional resistance of the falling hammer at time i. Once the drop hammer has completely separated from the electromagnetic chuck, the dynamic equation of the drop hammer is as follows: (M+m)g-f i -c i V i =(M+m)a i (2) (M+m)g-f i+1 -c i+1 V i+1 =(M+m)a i+1 (3) In the formula, c i V is the damping coefficient of the falling hammer at time i. i Let f be the contact velocity of the falling hammer at time i. i+1 c i+1 V i+1 These represent the frictional resistance, damping coefficient, and contact velocity of the falling hammer at time i+1, respectively. When H i and H i+1 When approaching infinitely, the approximate value of c is... i =c i+1 and f i =f i+1 Solve the following system of equations to get c i f i : c i =c i+1 =(M+m)(a i -a i+1 ) / (V i+1 -V i ) (4) f i =f i+1 =(M+m){g-a i -V i (a i -a i+1 ) / (V i+1 -V i )} (5) Substituting equation (5) into equation (1) and solving the equation yields F. i : F i =(M+m)V i (and i -a i+1 ) / (V i+1 -V i )(6) During the test, the sampling frequency of the data acquisition device was set to 10000Hz, with a time interval of 0.0001s. Every 0.0001s, the data acquisition device recorded and output an acceleration, which, after integration, output a velocity and a drop height. Substituting the velocity and drop height data into equations (4), (5), and (6) respectively, multiple sets of c were obtained. i f i and F i ， Obtained through data statistics , , .

2. The low-energy automotive interior collision impact device according to claim 1, characterized in that, The top and bottom ends of the sleeve guide rail are connected and fixed to the guide rail fixing device, which is arranged inside the column of the gantry frame.

3. The low-energy automotive interior collision impact device according to claim 1, characterized in that, The drop hammer consists of two parts: a hammer body and a hammer head. The hammer body is located at the top of the hammer head and has a safety through hole arranged in its radial direction. Its upper end is used to connect and cooperate with the electromagnetic chuck.

4. The low-energy automotive interior collision impact device according to claim 3, characterized in that, When performing the safety function, the safety pin passes radially through the sleeve guide rail and is installed in the safety through hole of the hammer body of the drop hammer.

5. The low-energy automotive interior collision impact device according to claim 1, characterized in that, The base is provided with leveling feet at its bottom to achieve leveling of the base.

6. The low-energy automotive interior collision impact device according to claim 1, characterized in that, The impact energy E is expressed by the following equation: E=0.5(M+m)V 2 , (M+m)gH-W1-W2-W3=0.5(M+m)V 2 。

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