JP2020204541A - Characteristic test method of automobile body - Google Patents

Abstract

To provide a characteristic test method of an automobile body for suppressing vibrations other than a target vibration due to preliminary vibration of a vibration device when vibrating the automobile body in a pulse shape.SOLUTION: A characteristic test method of an automobile body performs a test on vehicle body characteristics of an automobile body 31 by vibrating a table 3 with a slide mechanism in the one horizontal axial direction using the table 3 with the slide mechanism for fixing the automobile body 31, a movable shaft section 5 connected to the table 3 with the slide mechanism, the main body section 7 for vibrating the movable shaft section 5 in the one horizontal axial direction, and an electrodynamic vibration device 9 having main body section support means 11 for supporting the main body section 7 so as to be vibrated. The method includes: a preliminary vibration process for preliminarily vibrating the main body section 7 of the electrodynamic vibration device 9 with the movable shaft section 5 braked; and a vibration process for braking the main body section 7 preliminarily vibrated and canceling braking the movable shaft section 5, and vibrating the table 3 with the slide mechanism in a pulse shape through the movable shaft section 5.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for testing the characteristics of an automobile body, and more particularly to a method for testing the characteristics of an automobile body by vibrating the automobile body with a predetermined acceleration pattern to test the characteristics of the vehicle body related to steering stability of the vehicle.

Conventionally, tests have been conducted to evaluate rigidity as a vehicle body characteristic of an automobile body. As a test for evaluating the rigidity of the automobile body, for example, as described in Patent Document 1, the left and right damper mounting positions on either the front side or the rear side of the automobile body are fixed, and the opposite side is not fixed. By connecting actuators to each of the left and right suspension fastening parts and moving the left and right actuators in opposite phases, the entire vehicle body is twisted, and evaluation is generally performed by a torsional rigidity test that measures the torsion angle under a constant load. It has been

The rigidity evaluated in such a torsional rigidity test is a static evaluation value, and is useful for evaluating the rigidity of an automobile body as a structure. Therefore, it is also applied as an evaluation index of vehicle performance such as riding comfort based on the feeling of left-right shaking in the running test of an actual vehicle. However, as in the technique disclosed in Patent Document 1, although the torsional rigidity test generally performed in the past can obtain a static rigidity value as a structure, the vehicle body of an automobile body during running of an actual vehicle can be obtained. It was not possible to obtain a dynamic rigidity value, and the correlation with the sensory evaluation of vehicle performance such as steering stability and ride comfort evaluated in a running test by a test driver was weak.

The sensory evaluation by the running test of the vehicle is largely contributed by the suspension parts such as tires and suspension and the chassis structure, and the evaluation is not determined only by the performance of the vehicle body structure, but in the vehicle with insufficient vehicle body rigidity, the foot It is not possible to satisfy the sensory evaluation value only by adjusting the peripheral parts and chassis structure. Therefore, in order to obtain an index close to the sensory evaluation of vehicle performance in a laboratory test using an automobile body, it is important to measure at least the dynamic response behavior to a load.

Therefore, as a technique for measuring the dynamic response behavior of an automobile body, for example, in the above-mentioned torsional rigidity test, the load is continuously changed to give periodic torsional deformation, and the change in torsional angle and the deformation behavior of each part of the vehicle body are applied. A method of observing is conceivable. This method is useful as lab test data for vehicle body deformation with respect to vertical load input from the road surface via the front tires and suspension. However, since it is not possible to apply a load in the lateral direction (vehicle body width direction), it is not possible to know the dynamic response behavior when cornering or changing lanes.

When changing the direction of movement of a vehicle such as cornering or changing lanes, the power train or chassis transmits lateral force (load) to the vehicle body, and the entire vehicle changes the direction of movement. At this time, since the vehicle body is deformed by the force transmitted to the vehicle body, it is considered that there is a correlation between the dynamic response behavior of the vehicle body due to the force and the movement of the vehicle.
That is, when the rigidity of the vehicle body is high and the entire vehicle approaches a rigid body, the transient deformation of the vehicle body is small and the vehicle can smoothly change the direction of motion. On the other hand, when the rigidity of the vehicle body is low, elastic deformation of the vehicle body occurs with respect to a momentary load in the vehicle body width direction, and a time delay occurs in the movement of the entire vehicle. When the driver feels this time delay, he / she tends to perform extra steering operation, and a large steering angle and steering force are required as compared with a vehicle having a high rigidity of the automobile body, so that the steering stability is lowered. Affects evaluation. Therefore, it is considered that the dynamic response behavior of the vehicle body at the time of cornering or lane change has a strong correlation with the steering stability.

Further, the elastic deformation of the automobile body based on the inertial force generated at the time of cornering or changing lanes excites the automobile body to vibrate with the time delay of the vehicle body deformation. It is known that the period, magnitude, and convergence (damping) time of the excited vibration are related to the sensory evaluation value including the steering stability felt by the driver as well as the vehicle body rigidity. Therefore, suppressing the vibration of the vehicle body is an important factor in improving the vehicle body performance such as steering stability as well as the rigidity of the vehicle body. Then, when the numerical indexes of the dynamic response behavior of the vehicle body of these automobiles are obtained and the sensory evaluation items during actual vehicle driving can be evaluated based on the numerical indexes, the criteria and targets of the vehicle body structure are clarified, and the automobile. It will be easier to build vehicle performance at the vehicle body design stage.

As a technique for evaluating dynamic response behavior based on the vibration characteristics of an automobile body, Patent Document 2 evaluates the vibration characteristics of an automobile body by observing the vibration damping in the vertical direction that occurs when the automobile gets over a step. The method is disclosed. Many of these methods for evaluating the vibration characteristics of an automobile body focus on damping characteristics such as frequency (frequency) and vibration time (time constant, damping ratio) as numerical indexes to be used for evaluation.

In addition, as a method of evaluating the dynamic response behavior of the automobile body, a load is input or an impact is applied to a part of the automobile body, such as a vibration generator that vibrates the automobile body or a hammer that hits the automobile body. There is an experimental mode analysis that measures and analyzes the vibration generated in the entire vehicle body by giving. According to the experimental mode analysis, it is possible to estimate the resonance frequency (eigenvalue) of the structure of the vehicle body vibrating in a steady state and the vibration mode corresponding to each resonance frequency.

In a lane change or the like used as a running test of an actual vehicle related to a sensory evaluation of steering stability, a load in the horizontal and lateral directions due to handling acts only once momentarily to return to a straight running / steady state. Therefore, when evaluating such movements in a laboratory manner, especially from the viewpoint of stability when changing lanes, the deformation of the automobile body after the working load disappears is better than the steady-state vibration observation due to periodic stress application. Restoration behavior is important. Therefore, in a laboratory test using an automobile body, it is important to apply a pulsed load to the automobile body only once and to understand how the excited vehicle body vibration is attenuated and disappears.

Therefore, as disclosed in Patent Document 3, the inventor momentarily applies an inertial force in the horizontal and lateral directions to the entire vehicle body to excite the vibration of the vehicle body deformation and the dynamic rigidity of the vehicle body. So far, we have proposed a test method to evaluate. The test method uses a dynamic rigidity test device that combines a table with a slide mechanism that can move in the horizontal direction and an electrokinetic vibration device that vibrates the table with the slide mechanism in the horizontal uniaxial direction. ..
Then, in the test using the dynamic rigidity test device, the state of the actual vehicle in which the input of the load from the road surface when the vehicle is running is transmitted to the vehicle body through the suspension parts (suspension, wheels, axles, steering device, etc.). Is imitating. Then, an inertial force is generated in the entire automobile body due to the displacement of the floor portion of the automobile body fixed to the slide table, and the vibration excited by the inertial force can be measured.

Japanese Unexamined Patent Publication No. 2006-292737 JP 2015-161587 JP-A-2018-179637

However, although the method disclosed in Patent Document 2 is useful as laboratory test data regarding the vibration characteristics of the automobile body with respect to the vertical load input from the road surface via the front tires and suspension, the inertia acting on the automobile body. It is not possible to obtain the vibration characteristics of vehicle body deformation caused by force.

Further, in the experimental mode analysis for an automobile body, as described above, a load is input to a part of the automobile body or an impact is applied to measure and analyze the vibration generated in the entire automobile body. It is difficult to measure and analyze the vibration of vehicle body deformation caused by the inertial force acting on the entire vehicle body.

Further, in the test method disclosed in Patent Document 3, preliminary vibration (preliminary vibration) is performed prior to vibrating the automobile body with pulsed acceleration by the electrokinetic vibration device, and the object is It is necessary to apply a pulsed load to the vehicle body. Since the preliminary vibration excites the vibration with a small exciting force using the resonance phenomenon, unintended vibration is generated in the automobile body due to the preliminary vibration before the pulsed acceleration is applied depending on the type of the test piece. There was a case that it ended up. Therefore, when observing the vibration damping behavior of the vehicle body after vibrating with pulsed acceleration, the vibration of the vehicle body during preliminary vibration becomes noise, which may adversely affect the analysis accuracy of the vibration damping behavior. It was.

The present invention has been made to solve the above-mentioned problems, and is a vibration device for measuring and analyzing the vibration damping behavior excited by the automobile body by vibrating the automobile body with pulsed acceleration. It is an object of the present invention to propose a characteristic test method for an automobile body, which suppresses the occurrence of unintended vibration of the automobile body due to the preliminary vibration of the above and performs a test related to the vehicle body characteristics of the automobile body.

The inventor used a table with a slide mechanism and a characteristic test device equipped with an electrokinetic vibration device to perform a characteristic test of an automobile body, and in order to solve the above problems, the inventor used a table with a slide mechanism at a pulsed acceleration. Before exciting, we enthusiastically examined the means to suppress the generation of unintended vibration due to the preliminary vibration of the electrokinetic vibration device.

In order to suppress the generation of unintended vibration of the automobile body due to the preliminary vibration, it is not necessary to transmit the preliminary vibration of the electrokinetic vibration device to the table with the slide table mechanism. It is necessary to disconnect the mechanical connection of the electric vibrating device until just before the pulsed vibration, and connect it at the moment when the pulsed stress is applied to the vehicle body to be tested.
Here, the electrokinetic vibrating device vibrates the movable shaft portion in the axial direction by electromagnetic force, and the main body portion and the movable shaft portion of the electrokinetic vibrating device are not mechanically connected. I paid attention to. When the main body of the electrokinetic vibrating device is fixed to the floor surface or the like, even if the electrokinetic vibrating device and the table with the slite mechanism are mechanically separated, the main body of the electrokinetic vibrating device At the same time as the energization, the electrokinetic vibration device and the table with the slite mechanism are connected by electromagnetic force, and the preliminary vibration of the electrokinetic vibration device is transmitted to the table with the slide mechanism via the movable shaft portion. Therefore, we searched for a specific method to prevent the table with slide mechanism from vibrating even when the electrokinetic vibration device is energized and the main body and the table with slide mechanism are connected by electromagnetic force. As a result, a means for allowing the main body of the electrokinetic vibration device to move in the same direction as the vibration direction of the table with the slide mechanism is provided, and a means for maintaining the braked state so that the table with the slide mechanism does not vibrate is provided. It was conceived that the table with a slide mechanism should be prevented from vibrating during the preliminary vibration of the main body of the electrokinetic vibration device.
The present invention has been made based on such an idea, and specifically has the following configuration.

(1) The characteristic test method for an automobile body according to the present invention is a table with a slide mechanism that can fix the automobile body and can move in the horizontal uniaxial direction, and a movable shaft connected to the table with the slide mechanism. A vibrating device having a main body portion that vibrates the movable shaft portion in the horizontal uniaxial direction, a main body portion supporting means that supports the main body portion so as to vibrate in the horizontal uniaxial direction, and the horizontal one axis of the main body portion. Using the main body braking means for braking the vibration in the direction and the table-side braking means for braking the vibration in the horizontal uniaxial direction of the table with the slide mechanism, the table with the slide mechanism is horizontal with a predetermined acceleration pattern. The vehicle body is subjected to vibration in the uniaxial direction to test the vehicle body characteristics of the vehicle body, and the main body of the vibration device is set horizontally while the table with the slide mechanism is braked by the table-side braking means. The pre-vibration step of preliminarily vibrating in the uniaxial direction, the pre-vibrated main body portion is braked by the main body portion braking means, and the braking of the table with a slide mechanism by the table-side braking means is released. However, it is characterized by including a vibration step of vibrating the table with a slide mechanism with a predetermined acceleration pattern via the movable shaft portion.

According to the present invention, unintended vibration due to preliminary vibration in the vibrating device before vibrating the table with the slide mechanism is suppressed, and the vehicle body fixed to the table with the slide mechanism is vibrated with a predetermined acceleration pattern. Can be done.

It is a figure explaining each process of the characteristic test method of the automobile body which concerns on this embodiment ((a): preliminary vibration process, (b): vibration excitation process). It is a figure explaining the characteristic test apparatus of the automobile body used in the characteristic test method of the automobile body which concerns on embodiment of this invention. In the embodiment, it is a time response curve of acceleration in the vibration direction of the main body of the electrokinetic vibration device. In the embodiment, it is the result of measuring the time response curve of the acceleration in the vehicle body width direction of the automobile body (comparative example). In the embodiment, it is the result of measuring the time response curve of the acceleration in the vehicle body width direction of the automobile body (invention example).

The method for testing the characteristics of an automobile body according to the embodiment of the present invention is carried out using the characteristic test device 1 with the automobile body 31 as shown in FIG. 2 as a test target. Therefore, after explaining the automobile body 31 and the characteristic test device 1 to be tested, the characteristic test method of the automobile body according to the embodiment of the present invention will be described.

<Car body>
The automobile body 31 (see FIG. 2) to be tested in the present invention is a so-called white body (body-in-white) that does not include chassis, suspension parts, drive train parts, interior parts, etc., and is a body floor. It has a part and a suspension mount part for fastening the suspension.
Further, as will be described later, the automobile body 31 is provided with an accelerometer 33 that measures the acceleration of the automobile body 31 when the automobile body 31 is vibrated and braked.

<Characteristic test equipment for automobile bodies>
As shown in FIG. 2, the characteristic test device 1 includes a table 3 with a slide mechanism that can fix the automobile body 31 and can move in the horizontal uniaxial direction, and a movable shaft portion 5, a main body portion 7, and a main body portion. The electrokinetic vibration device 9 having the support means 11, the main body braking means 13, and the table-side braking means 15 are provided.

As the table 3 with a slide mechanism, a table 17 having a vibration table 17 on which the vehicle body 31 is placed and fixed, and a linear guide 19 that enables the vehicle body 31 to move linearly in the horizontal uniaxial direction together with the vibration table 17 are used. Can be done. It is assumed that the vibration table 17 and the linear guide 19 are supported by the table support structure 21 fixed to the floor surface 41.

The table 3 with a slide mechanism is provided with a jig for fixing the automobile body 31 on the vibration table 17. Then, the automobile body 31 is fixed to the vibration table 17 at a portion that can be an input point of a force (load) when traveling in an actual vehicle, such as a vehicle body floor portion and a suspension mount portion. Here, as the portion for fixing the automobile body 31, the vehicle body floor portion, the suspension mount portion, and the like may be appropriately selected depending on the content and purpose of the test for evaluating the vehicle body characteristics of the automobile body 31, and may be made of bolts or the like. It is desirable to use a rigid body connection.

In the present embodiment, the automobile body 31 is fixed to the vibration table 17 so that the horizontal uniaxial direction to be vibrated is the vehicle body width direction of the automobile body 31. Then, the automobile body 31 vibrated in the vehicle body width direction is elastically deformed due to a load caused by the inertial force.

The electrokinetic vibration device 9 is a vibration device that vibrates a table 3 with a slide mechanism fixed to an automobile body 31 in a horizontal uniaxial direction with a predetermined acceleration pattern, and is a movable shaft portion connected to the table 3 with a slide mechanism. 5. The main body 7 that vibrates the movable shaft portion 5 in the horizontal uniaxial direction, and the main body that can vibrate in the axial direction of the movable shaft portion 5 and in the direction of vibrating the table 3 with the slide mechanism (horizontal uniaxial direction). It has a main body supporting means 11 for supporting the portion 7.

As shown in FIG. 2, in the electrokinetic vibration device 9, the movable shaft portion 5 has an axial direction in which it vibrates and a horizontal uniaxial direction for vibrating the automobile body 31 so as to coincide with each other. Is located in.

The main body support means 11 includes a main body support cylinder 23 arranged so as to penetrate the main body 7 in the horizontal uniaxial direction, and a main body support that is fixed to the floor surface 35 to support both ends of the main body support cylinder 23. It has a shock absorber 27 provided between the structure 25 and the main body 7 and the main body support structure 25 to protect the main body 7.

The electrokinetic vibration device 9 used as the vibration device in the present embodiment is located between the magnet (drive coil) connected to the movable shaft portion 5 side and the electromagnet installed on the main body portion 7 side. An attractive force or a repulsive force is generated, and the attractive force or the repulsive force induces a relative displacement of the movable shaft portion 5 in the axial direction to generate vibration.

Further, it is assumed that the electrokinetic vibration device 9 includes a control device for driving the electrokinetic vibration device 9 so that the movable shaft portion 5 vibrates in a predetermined predetermined acceleration pattern as a target. As the control device, for example, the response behavior when the table 3 (vibration table 17) with a slide mechanism to which the vehicle body 31 is fixed is vibrated at a plurality of frequencies such as frequency sweep and white noise is measured in advance and slides. A table with a mechanism may be used that has a function of generating an input power pattern to be input to the electrokinetic vibration device 9 in order to vibrate and brake the table 3 with a predetermined acceleration pattern or displacement pattern.

The control device of the electrokinetic vibration device 9 is not specified as long as the table 3 with a slide mechanism can be vibrated with a pulsed acceleration pattern, but it is shocking like a single pulse wave. It is necessary to be able to generate a drive output.

When the electrokinetic vibration device 9 is driven with its main body 7 stopped, only the movable shaft 5 is displaced in the axial direction and vibrates in the horizontal uniaxial direction, and conversely, the movable shaft 5 is stopped. When driven in this state, the main body 7 is displaced in the axial direction of the movable shaft 5 and vibrates in the horizontal uniaxial direction. Therefore, the characteristic test device 1 used in the present embodiment is provided with a main body braking means 13 for braking the main body 7 and a table-side braking means 15 for braking the table 3 with a slide mechanism.

The main body braking means 13 is capable of braking and stopping the vibration of the main body 7 in the horizontal uniaxial direction with respect to the floor surface 35, and is fixed to the floor surface 35. .. As the main body braking means 13, for example, a brake shoe or a hydraulic cylinder can be used.

The table-side braking means 15 can brake the table 3 with a slide mechanism from vibrating in the horizontal uniaxial direction with respect to the floor surface 35 to prevent the table 3 from vibrating. As the table-side braking means 15, for example, a brake shoe can be used.

In the characteristic test device 1 shown in FIG. 1, the table-side braking means 15 is attached to the movable shaft portion 5 and brakes the movable shaft portion 5 to indirectly brake the table 3 with a slide mechanism. However, as another aspect of the table-side braking means 15, it may be connected to the vibration table 17 and directly brake the vibration in the horizontal uniaxial direction. In this case, the vibration of the movable shaft portion 5 may be braked by braking the vibration table 17. As such a table-side braking means, in addition to the brake shoes, a hydraulic cylinder connected to the vibration table 17 can be used.

The characteristic test device 1 may be provided with a device that integrates and controls the operations of the main body braking means 13 and the table-side braking means 15. In this case, the device that controls both the main body braking means 13 and the table-side braking means 15 can drive the electrodynamic vibration device 9 in synchronization with the control device of the electrodynamic vibration device 9 described above. Is preferable.

[Embodiment 1]
The characteristic test method for an automobile body according to the first embodiment of the present invention uses the characteristic test apparatus 1 illustrated in FIG. 1, and includes a preliminary vibration step and a vibration step. .. Hereinafter, each of the above steps will be described together with the operation of the characteristic test apparatus 1.

<Preliminary vibration process>
In the preliminary vibration step, the electrokinetic vibration device 9 is driven to move the main body 7 in the horizontal uniaxial direction while the table 3 with the slide mechanism is braked by the table side braking means 15 so as not to vibrate in the horizontal uniaxial direction. This is a preliminary vibration process.

<Vibration process>
In the vibrating step, the main body 7 preliminarily vibrated in the preliminary vibration step is braked by the main body braking means 13, and the braking of the table 3 with the slide mechanism by the table side braking means 15 is released to release the movable shaft portion. This is a step of vibrating the table 3 with a slide mechanism with a predetermined acceleration pattern via 5.
In the table excitation step of the present embodiment, the predetermined acceleration pattern for exciting the table 3 with the slide mechanism is defined as the acceleration pattern of the single pulse wave.

As described above, in the characteristic test method of the automobile body according to the present embodiment, the preliminary vibration step and the vibration step are provided, and the preliminary vibration of the electrokinetic vibration device 9 is transmitted to the table 3 with a slide mechanism. By preventing this, it is possible to suppress the occurrence of unintended vibration in the vehicle body 31 and vibrate the vehicle body 31 in a pulsed manner.

In the characteristic test device 1 used in the characteristic test method for the vehicle body according to the present embodiment, the electrokinetic vibration device 9 is used as the vibrating device, and the electrokinetic vibration device 9 is used in the preliminary vibration process. By preliminarily vibrating the main body 7 while braking the movable shaft portion 5, the vibration of the table 3 with a slide mechanism can be prevented, and the energy required for the subsequent pulse-like vibration of the table 3 with a slide mechanism can be obtained. It can be efficiently stored in the main body 7 as kinetic energy.

Further, in the subsequent vibration step, the main body 7 is braked by the main body braking means 13 at the moment when the repulsive force due to the electromagnetic force between the main body 7 of the electrokinetic vibration device 9 and the table 3 with the slide mechanism becomes maximum. At the same time, by releasing the braking of the table 3 with the slide mechanism by the table-side braking means 15, the kinetic energy of the main body 7 can be efficiently transferred to the table 3 with the slide mechanism, and the pulse-shaped acceleration pattern can be obtained. Can be generated.

After the table 3 with a slide mechanism is vibrated with a pulsed acceleration pattern, the vehicle body 31 on the table 3 with a slide mechanism is freely vibrated, and the damping behavior of this vibration is observed to stabilize the steering of the vehicle. It is possible to evaluate dynamic response behavior such as vibration damping behavior of the vehicle body according to the above. Then, the damping behavior of the free vibration of the automobile body 31 may be evaluated based on the time response curve of the acceleration acquired by the accelerometer 33 attached to the automobile body 31 as shown in FIG. 2, for example.

The characteristic test method for an automobile body according to the present embodiment has been described assuming that the characteristic test apparatus 1 shown in FIG. 1 is used as described above. However, the present invention is not limited to the one using the characteristic test apparatus 1 shown in FIG. 1, and in the preliminary vibration step, a means for vibrating only the main body 7 so that the table 3 with a slide mechanism does not vibrate is added. Any device may be used as long as it has a means for vibrating the table with a slide mechanism in a pulsed manner in the shaking process.

An experiment for confirming the action and effect of the characteristic test method for an automobile body according to the present invention has been conducted, and this will be described below.

In the experiment, the characteristic test device 1 shown in FIG. 2 was used to acquire the acceleration of the vehicle body 31 when the vehicle body 31 was vibrated in a pulse shape in the vehicle body width direction by the electrokinetic vibration device 9 as a vibration device. From the acquired acceleration, it was verified whether or not it is possible to prevent the preliminary vibration of the electrokinetic vibration device 9 from being transmitted to the vehicle body 31 and suppress the unintended vibration.

The vehicle body 31 used in the experiment was a white body of a compact car on the market (without doors, hood and fenders, equipped with bumper reinforcement and windshield, total weight 230 kg) and fixed to a table 3 with a slide mechanism. Here, the automobile body 31 is fixed to the vibration table 17 so as to coincide with the body width direction, which is the vibration direction.

As shown in FIG. 2, an accelerometer 33 was installed in the center of the inner roof rail of the automobile body 31 to measure the time response of acceleration. In this embodiment, as an accelerometer 33, a DC component detection type acceleration sensor having a frequency sensitivity of DC to 100 Hz and a maximum acceleration of 40 m / s ² for simultaneous measurement in three axial directions is installed on the vehicle body 31 in the vehicle body width direction and front and rear of the vehicle body. The acceleration in the direction and the vertical direction of the vehicle body was measured.

Further, in the experiment, a control program for driving the electrokinetic vibration device 9 was generated so as to vibrate the table 3 with a slide mechanism fixed to the vehicle body 31 with a target pulsed acceleration pattern, and the control program was generated. The electrokinetic vibration device 9 was driven to vibrate and brake the table 3 with a slide mechanism. The target pulsed acceleration pattern in this example was a half-signed single pulse wave with a maximum acceleration of 6.0 m / s ² and an action time of 50 ms.

In this embodiment, in the preliminary vibration step, the main body 7 is preliminarily vibrated while the movable shaft portion 5 of the electrokinetic vibration device 9 is braked, and in the subsequent table vibration step, the main body 7 is braked. An example of the invention was an example in which the braking of the movable shaft portion 5 was released and the table 3 with a slide mechanism was vibrated in a pulsed acceleration pattern via the movable shaft portion 5.

Here, 0.5 seconds before the pulsed vibration was set as the preliminary vibration period of the main body 7 in the preliminary vibration step, and the vibration output pattern of the electrokinetic vibration device 9 during that period was programmed. Further, at the same time as controlling the excitation output for driving the electrokinetic vibration device 9, the ON / OFF output of braking by the main body braking means 13 and the table side braking means 15 is integrated and controlled.

Specifically, the braking by the main body braking means 13 and the table side braking means 15 is such that the table 3 with the slide mechanism is braked by the table side braking means 15 in the preliminary vibration step, and the main body by the main body braking means 13. Preliminary vibration is started with the braking of the part 7 released.

Subsequently, at the position where the acceleration of the main body 7 in the vibration direction becomes maximum at the end of the preliminary vibration, that is, at the moment when the displacement speed of the main body 7 in the preliminary vibration becomes zero, the main body braking means 13 is operated to operate the main body. The unit 7 is braked. At the same timing, the braking of the table 3 with the slide mechanism by the table-side braking means 15 operated in the preliminary vibration step is released, and the table 3 with the slide mechanism is vibrated in a pulsed acceleration pattern.

In this way, after controlling the operations of the main body braking means 13 and the table side braking means 15 and exciting the table 3 with the slide mechanism in a pulsed acceleration pattern as described above, the main body braking means 13 and the table side The braking of the braking means 15 was released.
Then, as the dynamic response behavior of the automobile body 31, time-series data of acceleration was measured by the accelerometer 33.

In this embodiment, as a comparison target, the table 3 with a slide mechanism is not braked in the preliminary vibration process, and the electrokinetic vibration device 9 is pre-vibrated while the main body 7 is braked, and then the table 3 with a slide mechanism is used. Was vibrated with a pulsed acceleration pattern as a comparative example. Then, as in the invention example, the time series data of the acceleration in the automobile body 31 was measured.
In the comparative example as well, the installation position of the accelerometer 33 was set to the center of the roof rail inner of the automobile body 31 (see FIG. 2), as in the invention example.
For reference, an accelerometer was also installed in the main body of the electrokinetic vibration device 9 (not shown), and time-series data of acceleration was measured.

FIG. 3 shows the measurement results of the time series data of the acceleration in the main body 7 of the electrokinetic vibration device 9.
In the preliminary vibration step, the main body 7 is preliminarily vibrated, and after outputting a pulsed acceleration pattern, it is braked and the acceleration is attenuated.

4 and 5 show the measurement results of the acceleration time series data in the accelerometer 33 of the vehicle body 31 when the table 3 with the slide mechanism is vibrated by the electrokinetic vibration device 9 in a pulsed acceleration pattern. Here, FIG. 4 shows a comparative example, and FIG. 5 shows a result in an invention example.

In the comparative example shown in FIG. 4, the preliminary vibration of the electrokinetic vibration device 9 is transmitted to the vehicle body 31 in the preliminary vibration process. In the subsequent vibration step, unlike the pulse-shaped vibration of the automobile body 31, the purpose is that the acceleration of the accelerometer 33 located at a position away from the table 3 with the slide mechanism does not show any time phase difference. External vibration is occurring in the car body.

On the other hand, in the example of the invention shown in FIG. 5, the vibration of the automobile body 31 in the preliminary vibration process is hardly observed, and the vehicle body 31 is vibrated at a pulsed acceleration in the vibration process. From this, in the invention example, the preliminary vibration of the vibration device in the preliminary vibration process is prevented from being transmitted to the table with the slide mechanism, and the unintended vibration of the automobile body before the pulsed vibration is suppressed. You can see that there is.

As described above, according to the characteristic test method for an automobile body according to the present invention, unintended vibration is generated in the automobile body 31 by preventing the preliminary vibration of the electrokinetic vibration device 9 from being transmitted to the automobile body 31. It was demonstrated that the vehicle body 31 can be vibrated in a pulsed manner by suppressing the above.

1 Characteristic test device 3 Table with slide mechanism 5 Movable shaft 7 Main body 9 Electrodynamic vibration device 11 Main body support means 13 Main body braking means 15 Table side braking means 17 Vibration table 19 Linear guide 21 Table support structure 23 Main body Part support cylinder 25 Main body support structure 27 Cushioning body 31 Automobile body 33 Accelerometer 35 Floor surface

Claims (1)

A table with a slide mechanism that can fix the vehicle body and can move in the horizontal uniaxial direction, a movable shaft portion connected to the table with the slide mechanism, and a main body that vibrates the movable shaft portion in the horizontal uniaxial direction. A vibrating device having a main body supporting means for vibrating the main body and the main body in the horizontal uniaxial direction, a main body braking means for braking the vibration of the main body in the horizontal uniaxial direction, and a slide mechanism. Using the table-side braking means for braking the vibration of the attached table in the horizontal uniaxial direction, the table with the slide mechanism is vibrated in the horizontal uniaxial direction with a predetermined acceleration pattern, and the vehicle body characteristics of the automobile body are adjusted. It is a characteristic test method of the automobile body to be tested in
A preliminary vibration step of preliminarily vibrating the main body of the vibrating device in the horizontal uniaxial direction while the table with the slide mechanism is braked by the table-side braking means.
The preliminarily vibrated main body is braked by the main body braking means, the braking of the table with the slide mechanism by the table-side braking means is released, and the table with the slide mechanism is released via the movable shaft portion. A characteristic test method for an automobile body, which comprises a vibration step of vibrating a brake with a predetermined acceleration pattern.