JP2023003256A - Impact excitation test device, impact excitation test method, and impact excitation test program - Google Patents

Abstract

To appropriately and efficiently conduct a test to apply impact acceleration to a test piece.SOLUTION: An impact excitation test device comprises: an excitation table on which a test piece is mounted; a driving unit that drives the excitation table to apply acceleration to the test piece; and a control unit that controls the driving unit so that the test piece is applied with the acceleration indicated by a time history waveform including a shock pulse wave and adjustment excitation waves arranged temporally before and after the shock pulse wave. The control unit generates the time history waveform such that a total value of time integration values of the shock pulse wave and the adjustment excitation waves becomes 0 and a period of the adjustment excitation waves becomes 10 times or more a period of the shock pulse wave.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to an impact and vibration test apparatus, an impact and vibration test method, and an impact and vibration test program.

As a test apparatus for applying impact acceleration to a test object, for example, an impact vibration test apparatus is known that includes a vibration table on which the test object is placed and a drive unit that drives the vibration table and applies acceleration to the test object. (See Patent Document 1, for example). In the impact vibration test apparatus, for example, if the acceleration of a pulse wave that starts from zero and has only a component in a certain direction is defined as the excitation wave, the vibration table will continue to be displaced in one direction if it is excited according to this waveform. It will be. For this reason, in practice, for a shock pulse wave having a value in the excitation direction, a waveform having a value in the opposite direction to the excitation direction is included, and the time of the shock pulse wave and the waveform in the opposite direction to the excitation direction is The vibration table is driven so that the compensating vibration wave adjusted so that the total value of the integrated values becomes 0 is applied to the specimen.

Japanese Patent Application Laid-Open No. 2020-153870

In the impact vibration test, the feasibility of the test is evaluated by whether or not the time history waveform of the vibration acceleration is applied, and the floor response spectrum of the vibration table when the vibration is applied satisfies the target value. It may be done depending on whether you are doing it.

The floor response spectrum when a compensating excitation wave including a shock pulse wave and an adjusted excitation wave in the opposite direction to the excitation direction is applied to the test specimen is the floor response spectrum when the acceleration of the time history waveform of only the shock pulse wave is applied to the test specimen. In some cases, the values on the long-period side are lower than the floor response spectrum. If the value of the floor response spectrum on the long-period side does not reach the target value in this way, the test is performed in a state in which sufficient acceleration is not applied to the test object.

On the other hand, for example, it is conceivable to apply an acceleration that uniformly amplifies the values of the entire time zone of the initial time history waveform to the test object. Since the value also rises, it becomes an excessive excitation. In addition, in order to compensate for the drop in the long-period side of the floor response spectrum, it is conceivable to conduct a separate test in which acceleration having only long-period components is applied to the specimen. end up

The present disclosure has been made in view of the above, and an impact and vibration test apparatus, an impact and vibration test method, and an impact and vibration test program capable of appropriately and efficiently performing a test that applies impact acceleration to a test object. intended to provide

An impact and vibration test apparatus according to the present disclosure includes a vibration table on which a test object is placed, a driving unit that drives the vibration table and applies acceleration to the test object, a shock pulse wave, and a shock pulse wave that a control unit for controlling the driving unit so that an acceleration represented by a time history waveform including adjustment excitation waves arranged temporally before and after the test object is applied to the test object; The time history is adjusted so that the total value of the time integral values of the shock pulse wave and the adjustment excitation wave is 0, and the period of the adjustment excitation wave is ten times or more the period of the shock pulse wave. Generate a waveform.

The shock excitation test method according to the present disclosure includes placing a test specimen on a vibration table, applying a shock pulse wave and an adjustment excitation wave temporally before and after the shock pulse wave, respectively. A time history waveform in which the total value of the time integral values of the shock pulse wave and the adjustment excitation wave is 0, and the period of the adjustment excitation wave is 10 times or more the period of the shock pulse wave and driving the vibration table so that the acceleration indicated by the generated time history waveform is applied to the test object.

A shock excitation test program according to the present disclosure includes a shock pulse wave and adjustment excitation waves temporally positioned before and after the shock pulse wave, wherein the shock pulse wave and the adjustment excitation wave A process of generating a time history waveform in which the total value of the time integral values of is 0 and the period of the adjustment excitation wave is 10 times or more the period of the shock pulse wave, and the generated time history waveform is and driving a vibration table on which the specimen is placed so that the indicated acceleration is applied to the specimen.

Advantageous Effects of Invention According to the present disclosure, it is possible to appropriately and efficiently conduct a test in which an impact acceleration is applied to a specimen.

FIG. 1 is a diagram schematically showing an example of an impact vibration test apparatus according to this embodiment. FIG. 2 is a graph showing an example of a time history waveform. FIG. 3 is a flow chart showing an example of the impact vibration test method according to this embodiment. FIG. 4 is a graph showing a time history waveform input to the drive unit. FIG. 5 is a graph showing an example of a floor response spectrum when a time history waveform is input.

Embodiments of the impact and vibration test apparatus, the impact and vibration test method, and the impact and vibration test program according to the present disclosure will be described below with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, components in the following embodiments include components that can be easily replaced by those skilled in the art, or components that are substantially the same.

FIG. 1 is a diagram schematically showing an example of an impact vibration test apparatus according to this embodiment. As shown in FIG. 1 , the impact vibration test apparatus 100 includes a vibration table 10 , a driving section 20 and a control section 30 .

A test piece 40 is placed on the vibration table 10 . The test body 40 is an evaluation object for evaluating suitability for vibration. Examples of the test body 40 include, but are not limited to, nuclear facilities and the like. For example, aircraft equipment or structures, automobile equipment or structures, or other equipment or structures good.

The drive unit 20 drives the vibration table 10 so that acceleration (impact acceleration) is applied to the test object 40 . The drive unit 20 has a drive source (not shown) such as an electromagnetic coil, and a transmission mechanism (not shown) for transmitting the driving force generated by the drive source. The driving section 20 drives the vibration table 10 under the control of the control section 30 .

The control unit 30 controls driving by the driving unit 20 . The control unit 30 has a processing device such as a CPU (Central Processing Unit) and a storage device such as a RAM (Random Access Memory) or a ROM (Read Only Memory). The control unit 30 has a generation unit 31 , a drive control unit 32 and a storage unit 33 .

The generating unit 31 generates a time history waveform for driving the driving unit 20 . FIG. 2 is a graph showing an example of a time history waveform. The horizontal axis in FIG. 2 indicates time, and the vertical axis indicates acceleration. On the vertical axis of FIG. 2, the positive direction of acceleration is the excitation direction of the test body 40 . The negative direction of acceleration is the direction opposite to the excitation direction for the specimen.

As shown in FIG. 2 , the time history waveform 50 includes a shock pulse wave 51 and adjustment excitation waves 52 and 53 . The shock pulse wave 51 is set for a predetermined period T1 (hereinafter referred to as shock period T1) in chronological order. The shock pulse wave 51 is a trapezoidal waveform having an increasing portion 51a, a maintaining portion 51b, and a decreasing portion 51c. The increasing portion 51a is a portion where the acceleration increases from 0 with the passage of time. The maintenance portion 51b is a portion in which the acceleration remains constant after the increase portion 51a. The decreasing portion 51c is a portion where the acceleration decreases to 0 with the passage of time after the maintaining portion 51b. For the shock pulse wave 51, the length of each period and the magnitude of acceleration in the sustain portion 51b are set according to the test object 40, for example.

The adjustment excitation wave 52 is arranged in a period T2 (hereinafter referred to as an adjustment period T2) that precedes the shock pulse wave 51 in terms of time. The adjustment excitation wave 52 is set so as to be continuous with the shock pulse wave 51 . The adjustment excitation wave 52 has an acceleration portion 52a in which the acceleration has a positive value and a deceleration portion 52b in which the acceleration has a negative value. Note that the adjustment excitation wave 52 may not be provided with the acceleration portion 52a.

The adjustment excitation wave 53 is arranged in a period T3 (hereinafter referred to as an adjustment period T3) after the shock pulse wave 51 in terms of time. The adjustment excitation wave 53 is set so as to be continuous from the shock pulse wave 51 . The adjustment excitation wave 53 has an acceleration portion 53a in which the acceleration has a positive value and a deceleration portion 53b in which the acceleration has a negative value. Note that the adjustment excitation wave 53 may not be provided with the acceleration portion 53a.

The generation unit 31 generates the time history waveform 50 so that the total value of the time integral values of the shock pulse wave 51 and the adjustment excitation waves 52 and 53 is zero. That is, the generation unit 31 generates the time history waveform 50 so that the area of the region S1 in which the acceleration has a positive value and the area of the region S2 in which the acceleration has a negative value are equal.

Further, the generator 31 generates the time history waveform 50 so that each of the adjustment period T2 of the adjustment excitation wave 52 and the adjustment period T3 of the adjustment excitation wave 53 is ten times or more the impact period T1. The generation unit 31 generates the time history waveform 50 so as to be symmetrical with respect to the time axis.

The drive control unit 32 controls the operation of the drive unit 20 so that the acceleration indicated by the time history waveform 50 generated by the generation unit 31 is applied to the test object 40 .

The storage unit 33 stores various information. The storage unit 33 has storage such as a hard disk drive and a solid state drive. Note that an external storage medium such as a removable disk may be used as the storage unit 33 . The storage unit 33 stores programs, data, and the like used for processing in the generation unit 31 and the drive control unit 32 .

The storage unit 33 includes a shock pulse wave 51 and adjustment excitation waves 52 and 53 arranged temporally before and after the shock pulse wave 51, respectively. A process of generating a time history waveform 50 in which the total value of the time integral values of is 0 and the adjustment periods T2 and T3 are 10 times or more the impact period T1, and the acceleration indicated by the generated time history waveform 50 is An impact vibration test program for causing a computer to execute processing for driving the vibration table 10 on which the test piece 40 is placed so as to be applied to the test piece 40 is stored.

Next, an example of the impact vibration test method according to this embodiment will be described. The impact and vibration test method according to this embodiment uses the above-described impact and vibration test apparatus. FIG. 3 is a flow chart showing an example of the impact vibration test method according to this embodiment. As shown in FIG. 3, the impact vibration test method according to this embodiment includes a placement step S10, a waveform generation step S20, and a drive control step S30.

In the mounting step S10, the test piece 40 is mounted on the vibration table 10. As shown in FIG.

In the waveform generation step S20 , the generation unit 31 of the control unit 30 generates the time history waveform 50 of the acceleration applied to the test object 40 .

In the drive control step S30, the drive control section 32 of the control section 30 controls the driving of the drive section 20 so that the acceleration indicated by the time history waveform 50 generated by the generation section 31 is applied to the test object 40. FIG.

In drive control step S<b>30 , the drive unit 20 drives the vibration table 10 based on the control of the drive control unit 32 . Acceleration (impact acceleration) indicated by a time history waveform 50 is applied from the vibration table 10 to the test object 40 by driving the driving unit 20 .

FIG. 4 is a graph showing an example of a time history waveform. FIG. 4 shows a time history waveform (solid line portion) 50 according to the present embodiment and a time history waveform (broken line portion) 50A according to the comparative example generated by the generation unit 31 . In the graph of FIG. 4, the horizontal axis indicates time, and the vertical axis indicates acceleration.

The time-history waveform 50 according to the present embodiment and the time-history waveform 50A according to the comparative example have the same shock periods T1 and T5 in which the shock pulse waves 51 and 55 are arranged and the magnitude thereof. On the other hand, in the time history waveform 50 according to the present embodiment, the adjustment periods T2 and T3 of the adjustment excitation waves 52 and 53 are the adjustment periods T6 and T7 of the adjustment excitation waves 56 and 57 of the time history waveform 50A according to the comparative example. is longer with respect to Further, the absolute values of the adjustment excitation waves 52 and 53 of the time history waveform 50 are equal to It is smaller than the absolute values of the adjustment excitation waves 56 and 57 .

FIG. 5 is a graph showing an example of the floor response spectrum of the vibration table when the acceleration indicated by the time history waveform is applied to the test object 40. As shown in FIG. FIG. 5 shows a floor response spectrum (solid line portion) 70 for the time history waveform 50, a floor response spectrum (broken line portion; hereinafter referred to as a comparative spectrum) 70A for the time history waveform 50A according to the comparative example, and an impact spectrum. A floor response spectrum (a dashed-dotted line portion; hereinafter referred to as a target spectrum) 71 corresponding to the time history waveform of only the pulse wave 51 (55) is shown. In the graph of FIG. 5, the horizontal axis indicates the cycle logarithmically, and the vertical axis indicates the acceleration.

As shown in FIG. 5, the comparison spectrum 70A has a smaller acceleration value than the target spectrum 71 on the long period side (right side). The floor response spectrum 70 according to the present embodiment has acceleration values smaller than those of the target spectrum 71 on the high frequency side, but larger acceleration values than the comparison spectrum 70A. That is, the floor response spectrum 70 is in a state in which the drop on the high frequency side is suppressed with respect to the target spectrum 71 as compared to the comparison spectrum 70A. By lengthening the adjustment periods T2 and T3 of the adjustment excitation waves 52 and 53 in this manner, the drop in acceleration on the high frequency side in the floor response spectrum 70 is improved.

For example, in a test in which impact acceleration is applied to the specimen 40, if the floor response spectrum 70 obtained in the test exceeds the target spectrum 71 in the entire period band, it can be recognized as an effective test. Therefore, the adjustment periods T2 and T3 should be set so that the floor response spectrum 70 exceeds the target spectrum 71. FIG. In this case, the adjustment periods T2 and T3 can be set to a value ten times or more the impact period T1 of the impact pulse wave 51 in combination.

It can be estimated that the longer the adjustment periods T2 and T3 are, the more the drop in acceleration on the high frequency side in the floor response spectrum 70 is suppressed. The adjustment periods T2 and T3 can be appropriately set within a range allowed by, for example, test time restrictions.

Therefore, by setting both the adjustment periods T2 and T3 to a value that is ten times or more the impact period T1 within the range allowed by the constraints of the test time, the effectiveness of the test can be ensured and the test time can be shortened. It is possible to suppress the lengthening and efficiently perform the test. In addition to setting the adjustment periods T2 and T3 together to a value ten times or more the impact period T1, the acceleration amplitude level may be increased over the entire acceleration time history waveform.

As described above, the impact vibration test apparatus 100 according to the present embodiment includes the vibration table 10 on which the test piece 40 is placed, and the drive unit 20 that drives the vibration table 10 and applies acceleration to the test piece 40. , the shock pulse wave 51 and the adjustment excitation waves 52, 53 arranged temporally before and after the shock pulse wave 51, respectively, such that the acceleration represented by the time history waveform 50 is applied to the test body 40. and a control unit 30 for controlling the drive unit 20. The control unit 30 makes the total value of the time integral values of the shock pulse wave 51 and the adjustment excitation waves 52 and 53 equal to 0, and makes the adjustment periods T2 and T3 equal to the shock. The time history waveform 50 is generated so as to be ten times or more the period T1.

The impact and vibration test method according to the present embodiment includes placing the test piece 40 on the vibration table 10, and adjusting the shock pulse wave 51 and the adjustment that is arranged before and after the shock pulse wave 51 in terms of time. including the excitation waves 52 and 53, the total value of the time integral values of the shock pulse wave 51 and the adjustment excitation waves 52 and 53 is 0, and the adjustment periods T2 and T3 are 10 times or more the impact period T1. It includes generating a time history waveform 50 and driving the vibration table 10 so that the acceleration indicated by the generated time history waveform 50 is applied to the test object 40 .

The shock excitation test program according to the present embodiment includes a shock pulse wave 51 and adjustment vibration waves 52 and 53 arranged temporally before and after the shock pulse wave 51, respectively. A process of generating a time history waveform 50 in which the total value of the time integral values of the adjustment excitation waves 52 and 53 is 0 and the adjustment periods T2 and T3 are ten times or more the impact period T1, and the generated time history and a process of driving the vibration table 10 on which the test piece 40 is placed so that the acceleration indicated by the waveform 50 is applied to the test piece 40 .

According to this configuration, by setting the adjustment periods T2 and T3 at least ten times as long as the impact period T1, it is possible to suppress the drop in the acceleration on the long-period side in the floor response spectrum 70, thereby prolonging the test time. Temporalization is suppressed. As a result, the test in which acceleration is applied to the specimen 40 can be performed appropriately and efficiently.

In the impact vibration test apparatus 100 according to the present embodiment, the shock pulse wave 51 has an increasing portion 51a where the acceleration increases from 0, a maintaining portion 51b where the acceleration is maintained, and a decreasing portion 51c where the acceleration decreases to 0. The adjusted excitation waves 52 and 53 are waveforms having acceleration portions 52a and 53a in which the acceleration has a positive value and deceleration portions 52b and 53b in which the acceleration has a negative value. . According to this configuration, the waveform of the entire time history waveform 50 can be adjusted with high accuracy.

In the impact vibration test apparatus 100 according to this embodiment, the time history waveform 50 is formed symmetrically in the direction of the time axis. According to this configuration, the waveform of the entire time history waveform 50 can be adjusted with high accuracy.

The technical scope of the present invention is not limited to the above embodiments, and modifications can be made as appropriate without departing from the scope of the present invention.

10 Vibration table 20 Drive unit 30 Control unit 31 Generation unit 32 Drive control unit 33 Storage unit 40 Test object 50, 50A Time history waveforms 51, 55 Shock pulse wave 51a Increasing portion 51b Maintaining portion 51c Decreasing portions 52, 53, 56, 57 Adjustment excitation waves 52a, 53a Acceleration portions 52b, 53b Deceleration portion 70 Floor response spectrum 70A Comparison spectrum 71 Target spectrum 100 Impact excitation test devices S1, S2 Regions T1, T5 Impact periods T2, T3, T6, T7 Adjustment periods

Claims (5)

a vibration table on which the test piece is placed;
a drive unit that drives the vibration table to apply acceleration to the test object;
The driving unit is controlled so that an acceleration represented by a time history waveform including a shock pulse wave and adjustment excitation waves arranged temporally before and after the shock pulse wave is applied to the test object. with a control and
The control unit controls the total value of the time integral values of the shock pulse wave and the adjustment excitation wave to be 0, and the period of the adjustment excitation wave to be ten times or more the period of the shock pulse wave. An impact vibration test device that generates the time history waveform. The shock pulse wave is a trapezoidal waveform having an increasing portion in which the acceleration increases from 0, a maintaining portion in which the acceleration is maintained, and a decreasing portion in which the acceleration decreases to 0,
2. The impact vibration test apparatus according to claim 1, wherein the adjusted excitation wave is a waveform having an acceleration portion in which acceleration has a positive value and a deceleration portion in which acceleration has a negative value. The impact vibration test apparatus according to claim 1 or 2, wherein the time history waveform is formed so as to be symmetrical in the direction of the time axis. placing the specimen on a vibration table;
including a shock pulse wave and an adjustment excitation wave temporally before and after the shock pulse wave, wherein the total value of the time integral values of the shock pulse wave and the adjustment excitation wave is 0; and generating a time history waveform in which the period of the adjustment excitation wave is ten times or more the period of the shock pulse wave, and applying the acceleration indicated by the generated time history waveform to the test object. and driving the vibration table to the impact vibration test method. including a shock pulse wave and an adjustment excitation wave temporally before and after the shock pulse wave, wherein the total value of the time integral values of the shock pulse wave and the adjustment excitation wave is 0; and a process of generating a time history waveform in which the period of the adjustment excitation wave is ten times or more the period of the shock pulse wave;
An impact vibration test program for causing a computer to execute a process of driving a vibration table on which the test object is placed so that the generated acceleration indicated by the time history waveform is applied to the test object.

Images