Vibration test method and vibration device

Abstract

To provide a method for running a vibration test which can re-create vibrations and has a high efficiency in a process of transferring a storage body.SOLUTION: The method for running a vibration test according to the present invention includes a vibration application step of applying a vibration on a storage body 12 storing a plurality of items 11. The vibration application step is a step of applying a vibration on the storage body 12 on the basis of accumulated fatigue. The accumulated fatigue is calculated on the basis of a relative acceleration as the difference of acceleration among a plurality of measurement targets 10a and 10b in the storage body 12. The method for running a vibration test desirably includes a preliminary step prior to the vibration application step, of measuring the relative acceleration while setting the storage body 12 storing the items 11 in a transfer state.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vibration testing method. [Background technology]

[0002] In the distribution process of goods and the like, the container in which the goods are stored may be subjected to vibration, which may cause deformation or damage to the goods. Vibration testing is known in which such vibration is reproduced to evaluate the presence or absence of deformation or damage to the goods. For example, Patent Document 1 discloses a vibration testing method that includes a step of calculating the accumulated fatigue occurring in the transported goods under the transport conditions in actual transportation as theoretical accumulated fatigue, and a step of vibrating the transported goods for a predetermined period of time at the vibration acceleration under the transport conditions through a vibration test using a vibration table, and calculating the accumulated fatigue as actual fatigue from the vibration acceleration occurring in the transported goods, and repeating the vibration test with increasing the vibration acceleration of the vibration table until the actual fatigue becomes equal to the theoretical accumulated fatigue.

[0003] Furthermore, the JIS specifies test methods for evaluating the durability of the contents or packaging of transported goods against vertical vibrations that the transported goods are subjected to during transportation (Non-Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-181195 A [Non-Patent Document 1] JIS Z 0200_2013 General rules for performance test methods for packaged goods [Non-Patent Document 2] JIS Z 0232_2004 Packaged cargo-Vibration test method Summary of the Invention [Problem to be solved by the invention]

[0005] From the viewpoint of grasping the durability of products and packages against vibration, vibration tests are required to reproduce vibrations that match actual transport conditions. Although the vibration test methods of Patent Document 1 and Non-Patent Documents 1 and 2 reproduce the vibrations of transport means such as vehicles that generate vibrations, the degree of damage to products caused by the vibrations of the vibration test methods is different from the degree of damage to products caused on actual transport routes. In particular, it is difficult to reproduce the degree of damage to products contained in a container using conventional vibration tests. In addition, due to the difficulty of such reproduction, the vibration time tends to be long, making it difficult to perform the test efficiently.

[0006] Therefore, the present invention relates to providing a vibration test method that can provide highly reproducible and efficient vibration during transportation of a package. [Means for solving the problem]

[0007] The present invention relates to a vibration testing method. In one embodiment, the vibration testing method preferably includes a vibration application step of applying vibration to a container in which a plurality of articles are contained. In one embodiment, the vibration applying step is preferably a step of applying vibration to the container based on accumulated fatigue. The accumulated fatigue is calculated based on a relative acceleration, which is a difference in acceleration between a plurality of measurement objects in the container. Effect of the Invention

[0008] According to the vibration test method of the present invention, the vibration during the transportation of the package can be highly reproducible and efficient. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic explanatory diagram showing an embodiment of a vibration testing method according to the present invention. [Diagram 2] FIG. 2 is a plan view showing the positional relationship between the articles contained in the container shown in FIG. 1 and the acceleration sensor. [Diagram 3]FIG. 3 is a graph showing the change in relative acceleration over time. [Figure 4] FIG. 4 is a perspective view for explaining articles in a container in a transport state. [Diagram 5] FIG. 5 is a flow diagram of a vibration process performed by the vibration device shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present invention will now be described based on preferred embodiments with reference to the drawings. The vibration test method of this embodiment includes a preliminary step of measuring the relative acceleration in a transport state, and a vibration application step of applying vibration to a container 12 containing a plurality of items 11 (see FIG. 1). Details of the relative acceleration will be described later.

[0011] The container 12 has an internal storage space for storing a plurality of items 11. The container 12 may be a packaging material that reflects the transportation conditions, such as a cardboard box, a wooden box, a plastic container, etc. From the viewpoint of versatility, it is preferable to use a cardboard box as the container 12.

[0012] The article 11 may be anything depending on the purpose of the vibration test. For example, the article 11 may be a product that is transported (distributed) while being housed in a container 12, or a prototype in the development stage. The container 12 of this embodiment is a cardboard box 17, and the items 11 contained in the container 12 are packaging containers 16 filled with detergent (see FIG. 1). The container 12 has a longitudinal direction X, a width direction Y perpendicular to the longitudinal direction X, and a height direction Z along the vertical direction (see FIG. 4), and four rows of three packaging containers 16 lined up in the width direction Y are lined up along the longitudinal direction X. That is, the container 12 of this embodiment contains twelve packaging containers 16.

[0013] In the vibration testing method of this embodiment, a plurality of measurement objects 10a, 10b are set for a housing 12 housing a plurality of articles 11. The plurality of measurement objects 10a, 10b may be the articles 11, may include the articles 11 and the housing 12, or may be only the housing 12. When the measurement objects 10a and 10b include articles 11, the measurement objects 10a and 10b are selected from the multiple articles 11 in the container 12. When the measurement objects 10a and 10b are the same articles 11, multiple different articles 11 are selected in the container 12 and are set as the measurement objects 10a and 10b. When the measurement objects include the container 12, the measurement objects 10a and 10b are selected from the inner wall of the container 12, i.e., the portion of the container 12 facing the article 11. For example, a portion of the peripheral wall rising from the bottom surface of the container 12 is selected as the measurement object. The number of objects to be measured can be two or more, and may be three or more.

[0014] In the vibration test method of this embodiment, two packaging containers 16a, 16b in the container 12 are taken as measurement objects 10a, 10b. Acceleration sensors A1, A2 are attached to the measurement objects (see FIG. 2). Any acceleration sensors capable of continuously measuring acceleration can be used as the acceleration sensors A1, A2, without any particular restrictions. These acceleration sensors A1, A2 measure acceleration in three directions, the XYZ axes (horizontal and vertical directions). In this embodiment, these acceleration sensors A1 and A2 are hereinafter also referred to as the "first acceleration sensor A1" and the "second acceleration sensor A2." The first acceleration sensor A1 is attached to one packaging container 16a, and the second acceleration sensor A2 is attached to a packaging container 16b other than the packaging container 16a to which the first acceleration sensor A1 is attached.

[0015] In order to more reliably obtain reproducibility of damage caused by vibration, it is preferable that the selection of the measurement objects 10a, 10b in the housing 12 and the attachment of the acceleration sensors A1, A2 are performed in common between the preliminary step and the vibration application step.

[0016] In the preliminary step and the vibration step, the acceleration between the multiple measurement objects 10a, 10b in the housing 12 is measured, and further, the relative acceleration, which is the difference between these accelerations, is measured. From the viewpoint of further improving the reproducibility of damage caused by vibration, the acceleration between the multiple measurement objects 10a, 10b for calculating the relative acceleration is preferably the acceleration in the vertical direction. In the vibration test method of this embodiment, the difference (G1-G2) between the vertical acceleration (G1) measured by the first acceleration sensor A1 and the vertical acceleration (G2) measured by the second acceleration sensor A2 is defined as the relative acceleration. The relative acceleration between the multiple measurement objects 10a, 10b in the housing 12 is hereinafter also referred to simply as the "relative acceleration."

[0017] In the preliminary step, the acceleration between the multiple measurement objects 10a, 10b in the transported state is measured, and the relative acceleration, which is the difference between these accelerations, is measured. In this preliminary step, the change over time in the relative acceleration while the container 12 is being transported is measured. That is, the acceleration difference (relative acceleration) between the measurement objects 10a, 10b in the container 12 transported by a transport means 18 such as a vehicle is continuously measured (see FIG. 1). The change in relative acceleration over time measured in the preliminary step may be measured for the entire section of the transportation route from the starting point to the destination, or may be measured for only a portion of the transportation route. In the latter case, the change in relative acceleration over time for the entire transportation route may be predicted from the change in relative acceleration over time for the portion of the transportation route, and the predicted value may be used as the change in relative acceleration over time obtained in the preliminary step.

[0018] The transportation means 18 for transporting the container 12 in the preliminary process is not particularly limited, and can be any one of land transportation using vehicles or railways, sea transportation using ships or the like, and aerial transportation using aircraft or drones or the like, or a combination of these transportation methods. In the present embodiment, the transportation state in the preliminary process is a state in which the product is transported by land.

[0019] In the preliminary process of this embodiment, for one of the multiple packages 12 loaded on the platform of the transport means 18, a first acceleration sensor A1 is attached to a packaging container 16a inside the package 12, and a second acceleration sensor A2 is attached to another packaging container 16b inside the package 12, and the relative accelerations thereof are measured (see FIG. 2). In the preliminary process of this embodiment, the acceleration sensors A1 and A2 output and record, by wire or wireless, one or both of acceleration data and relative acceleration data to a recorder (not shown) during transportation. In this way, in the preliminary process of this embodiment, by continuously measuring the relative acceleration during transportation, a graph of the change over time in the relative acceleration during transportation can be obtained (see FIG. 1).

[0020] It is preferable to carry out a preliminary vibration test under different transport conditions and accumulate the information corresponding to each transport condition. News and Examples of such information include information on the measurement objects 10a and 10b, the relative acceleration of the measurement objects 10a and 10b, accumulated fatigue based on the relative acceleration, profile information such as power spectrum density, and information on the transportation route, etc. The information on the transportation route includes information on the departure point, destination, mileage, type of vehicle, loading position on the loading platform, road surface condition, etc. In the vibration testing method of this embodiment, the corresponding information is stored in the control device 20, which will be described later. Furthermore, profile information out of the corresponding information is accumulated as a relative acceleration condition, which will be described later.

[0021] The vibration application step of this embodiment is carried out by a vibration testing device 30 and a vibration device 100 including a control device 20 that controls the vibration testing device 30 (see FIG. 1). The vibration test device 30 includes a vibration table 35 on which an object to be vibrated is placed, and a vibration generating unit 31 that vibrates the vibration table 35. The vibration test device 30 may be any known vibration test device, such as a mechanical type, an electrodynamic type, or a hydraulic type.

[0022] The control device 20 is a device that controls the operation of the vibration generating unit 31 and analyzes the relative acceleration and accumulated fatigue of the measurement objects 10a, 10b, and includes a condition extracting unit 21, a vibration calculating unit 23, and a control unit 25. The details of accumulated fatigue will be described later.

[0023] The condition extraction unit 21 extracts a desired condition from the pre-stored relative acceleration conditions in response to an operation by an operator. Information on a plurality of relative acceleration conditions is stored in the control device 20, and the condition extraction unit 21 reads the desired relative acceleration condition from the information and outputs it to a display unit (display) and vibration calculation unit 23 provided in the control device 20. The information on the relative acceleration conditions includes information on the change over time of the relative acceleration in the transport state obtained in the preliminary step (hereinafter also referred to as "transportation relative acceleration information") or information on the change over time of the relative acceleration obtained in the non-transport state (hereinafter also referred to as "non-transportation relative acceleration information"), as well as information on the mounting positions of the acceleration sensors A1 and A2 in the container 12, etc.

[0024] The transport relative acceleration information is preferably associated with information on the vibration behavior (frequency, amplitude, waveform, vibration time) during transport and the transport route. The non-transportation relative acceleration information may be, for example, information on the change over time in relative acceleration when the measurement object is vibrated until damage occurs using the vibration test device 30. It is preferable that the non-transportation relative acceleration information is associated with information on the operation settings of the vibration test device 30.

[0025] The condition extraction unit 21 calculates the accumulated fatigue based on the relative acceleration of the extracted relative acceleration condition. That is, the accumulated fatigue is calculated from the change over time in the relative acceleration. The accumulated fatigue calculated by the condition extraction unit 21 corresponds to the "target accumulated fatigue" described later.

[0026] The excitation calculation unit 23 adjusts the operation of the vibration test device 30 so that the accumulated fatigue based on the relative acceleration in the container 12 subjected to the vibration test becomes equivalent to the accumulated fatigue (target accumulated fatigue) calculated by the condition extraction unit 21. That is, the excitation calculation unit 23 adjusts the vibration behavior of the vibration test device 30. The vibration behavior includes the relative acceleration, the vibration frequency, the vibration time, the acceleration, the waveform, and the like. The vibration calculation unit 23 adjusts at least one of the vibration frequency, vibration time, acceleration, and waveform while the vibration testing device 30 is operating, i.e., when vibration is being applied to the housing 12, so that the accumulated fatigue based on the relative acceleration in the housing 12 becomes equivalent to the target accumulated fatigue. The control unit 25 controls the operation of the vibration test device 30 based on a signal from the vibration calculation unit 23. In this way, the vibration test device 30 can apply vibration to the accommodation body 12 that is the vibration target under the control of the vibration calculation unit 23.

[0027] The control device 20 includes a CPU, a ROM (Read Only Memory), a RAM (Random Access Memory), a flash memory, a camera, a display unit, an input device for a user to perform input operations, and the like. The CPU may include a graphics processor (Graphics Processing Unit (GPU)) for displaying images, a multimedia processor for encoding and decoding High-Definition (HD) video and the like, a display controller for controlling the display, and a power management Integrated Circuit (IC) for controlling power supply and charging, and the like. The display unit of the control device 20 may be a touch panel or the like having both display and operation functions. Examples of the input device include a touch panel, a keyboard, a keypad, a touchpad, a mouse, a microphone, and the like. An operator of the control device 20 operates the control device 20 using an input device. The processes performed by each control device 20 are realized by a CPU expanding a program stored in a ROM, a disk, etc., into a RAM and executing the program. The processes may be realized by an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array), or may be realized by a combination of an ASIC and an FPGA.

[0028] In the vibration step of this embodiment, vibration is applied to the container 12 so that the accumulated fatigue based on the relative acceleration between the measurement objects 10a, 10b in this step is equivalent to the accumulated fatigue based on the relative acceleration obtained in the preliminary step (see FIG. 1). Such accumulated fatigue is based on an S-N curve. The accumulated fatigue is calculated by the following formula (1).

[0029]

number

[0030] In the above formula (1), "β" is "accumulated fatigue" and is calculated from a graph (waveform) showing the change over time in relative acceleration. The graph is a waveform in which the relative acceleration alternates between positive and negative peaks, centered around the zero axis. In the above formula (1), each peak in this waveform is "i", and the relative acceleration of each peak is "G1-G2". Also, in the above formula (1), "α" is the "acceleration coefficient". In other words, the accumulated fatigue (β) calculated by the above formula (1) is the value (|g i | α ) is the sum of all the For example, in the graph shown in Figure 3, the sum of the absolute values ​​of the peak values ​​in the 12 vibrations (frequencies) raised to the power of α (|g1| α +|g2| α +|g3| α +····+|g 11 | α +|g 12 | α) is the accumulated fatigue of relative acceleration.

[0031] The "α" is the slope of the S-N curve of the measurement objects 10a and 10b, and is a value specific to the measurement object. The larger the value of "α", the higher the sensitivity of damage to acceleration. When the materials of the multiple measurement objects 10a, 10b are different, for example when the measurement objects are the container 12 and the item 11 (packaging container 16 in this embodiment), "α" is a value specific to the measurement object being evaluated for damage due to vibration.

[0032] The vibration step of this embodiment includes an accumulated fatigue determination step of calculating accumulated fatigue based on the relative acceleration, a vibration condition setting step of setting vibration conditions of the vibration test device 30, and a vibration step of vibrating the container 12. In the accumulated fatigue determination process, a desired condition is extracted from the information on relative acceleration conditions stored in the control device 20, and accumulated fatigue (hereinafter also referred to as "target accumulated fatigue") is calculated based on the relative acceleration of the desired condition. The extraction of the relative acceleration condition is performed by the condition extraction unit 21 of the control device 20 described above in response to an operation by the operator. In addition, the calculation of the target accumulated fatigue based on the relative acceleration of the extracted relative acceleration condition is also performed by the condition extraction unit 21 of the control device 20 described above.

[0033] In the accumulated fatigue determination step, for example, the conditions under which the transport means 18 transports the object from point C1 to point C2 in response to an operation by an operator are selected. Then, the target accumulated fatigue is calculated from the change over time in the relative acceleration in the container 12 under these conditions.

[0034] In the vibration condition setting step, one or more of the vibration frequency, vibration time, acceleration, and waveform of the acceleration are set as vibration conditions for the vibration test device 30. The vibration condition setting process of this embodiment sets a combination of vibration frequency and acceleration range. In this process, the vibration calculation unit 23 of the control device 20 described above sets any frequency and acceleration in response to an operation by an operator. For example, the operator can set the vibration of the vibration testing device 30 to a waveform such as a sine wave, and can also set the frequency or acceleration range.

[0035] In the vibration step of this embodiment, a housing 12 having the same configuration as in the preliminary step is prepared, acceleration sensors A1 and A2 are attached to the same measurement objects 10a and 10b as in the preliminary step, and vibration is applied to the housing 12 while monitoring accumulated fatigue based on the relative acceleration of the measurement objects 10a and 10b. The vibration step is executed by the vibration testing device 30 under the control of the vibration calculation unit 23 and the control unit 25 of the control device 20. In the vibration process, vibration is continuously applied to the container 12 so that the accumulated fatigue becomes equivalent to the target accumulated fatigue determined in the accumulated fatigue determination process. In other words, the container 12 including the measurement objects 10a, 10b placed on the vibration table 35 is vibrated, and the vibration test device 30 is operated until the accumulated fatigue based on the relative acceleration between the measurement objects 10a, 10b (hereinafter also referred to as "actual accumulated fatigue") becomes equivalent to the target accumulated fatigue. In other words, the vibration time is adjusted so that the actual accumulated fatigue becomes equivalent to the target accumulated fatigue. With such a configuration, a reproduction test of the transportation state can be performed with very simple control.

[0036] In the control performed in the vibration step of this embodiment, the vibration test device 30 is operated under the vibration conditions set in the vibration condition setting step, except for the vibration time. In this manner, in the vibration step of this embodiment, vibration is applied to the container 12 under conditions corresponding to the target accumulated fatigue.

[0037] The vibration step may be performed while monitoring the measured accumulated fatigue as described above, or may be performed by predetermining vibration test conditions under which the measured accumulated fatigue is equivalent to the target accumulated fatigue. In the latter case, a vibration test is performed at any frequency and acceleration using the vibration test device 30, the accumulated fatigue is measured based on the relative acceleration per unit time, and the vibration time equivalent to the target accumulated fatigue under the above-mentioned frequency and acceleration conditions is determined. The vibration test conditions (hereinafter also referred to as "assumed equivalent conditions") having such frequency, acceleration, and vibration time can be considered as the measured accumulated fatigue when vibrated under said conditions being equivalent to the target accumulated fatigue. The vibration step performed under these assumed equivalent conditions is preferable in terms of the simplicity of the vibration test, since there is no need to monitor the measured accumulated fatigue.

[0038] As described above, the vibration process of this embodiment applies vibration to the container 12 based on the target accumulated fatigue. This accumulated fatigue is based on the relative acceleration reflecting the displacement difference between the measurement objects 10a, 10b, such as a part of the container 12 and the object 11 in the transport state. As a result, the vibration process of this embodiment can easily reflect a collision between the container 12 and the object 11 or a collision between the objects 11 (see FIG. 4) that may occur in the container 12 due to vibration in the transport state, and can reproduce damage caused by vibration in the container 12 with high reproducibility. On the other hand, the conventional vibration test method reproduces the vibration behavior of the vibration source (for example, the loading platform of the means of transportation), so it is difficult to reflect the vibration behavior occurring in the container 12, and the reproducibility of damage that may occur in the actual transport state is low. The specific effect of the reproducibility of the vibration process based on the accumulated fatigue will be shown in the examples described later. In addition, in conventional vibration testing methods, the phase shift of each measurement object varies, which causes damage to vary depending on the frequency. In contrast, in the vibration process of this embodiment, the accumulated fatigue is based on the relative acceleration, which reduces the variation in the phase shift between the measurement objects, thereby suppressing the effect of frequency. Furthermore, by setting the target accumulated fatigue as a target value, it is possible to easily set the frequency and duration of the vibration applied to the housing 12. This makes it easy to narrow down the frequency of the vibration to a specific range, and also makes it possible to shorten the duration of the vibration, thereby enabling efficient vibration testing.

[0039] In the vibration test method of this embodiment, the vibration process is performed while monitoring the measured accumulated fatigue, but the vibration test conditions of the vibration process can be repeatedly used. By performing the vibration process, the vibration conditions and operating time (vibration time) of the vibration test device 30 for becoming equivalent to the target accumulated fatigue can be grasped, and the conditions corresponding to the target accumulated fatigue can be obtained. In other words, the operating conditions of the vibration test device 30 for the measured accumulated fatigue to reach the value of the target accumulated fatigue (hereinafter also referred to as "conditions corresponding to accumulated fatigue") can be grasped from the vibration process.

[0040] From the viewpoint of performing the vibration test more easily, the vibration test method of this embodiment preferably includes a repeating step in which the assumed equivalent condition or the accumulated fatigue corresponding condition is applied to another container 12. In the repeating step, the container 12 is subjected to vibration under the same conditions as the container state and under the assumed equivalent condition or the accumulated fatigue corresponding condition. In the repeating step, vibration is applied under the same conditions as in the vibration step, so that a load equivalent to the target accumulated fatigue of the vibration step can be applied to the measurement objects 10a, 10b. This makes it possible to perform the vibration test more efficiently and easily, and in particular makes it easier to perform a comparative durability test of the packaging material used for the item 11.

[0041] In the vibration test method of this embodiment, the multiple measurement objects 10a, 10b in the container 12 may be arranged in a spaced apart state or adjacent to each other. From the viewpoint of further improving the reproducibility of the collision between the container 12 and the article 11 or the collision between the articles 11 due to vibration, the multiple measurement objects 10a, 10b are preferably the articles 11 accommodated in the container 12 so as to be able to come into contact with each other. In this case, the measurement objects 10a, 10b may be, for example, packaging containers 16a, 16b adjacent to each other in the longitudinal direction X or width direction Y in the container 12 (see Figs. 2 and 4). The multiple measurement objects 10a, 10b may be adjacent to each other via a cushioning material, a partition, or the like.

[0042] From the viewpoint of further improving the reproducibility of damage caused by vibration, it is preferable that the multiple measurement objects 10a, 10b are the items that are most damaged by vibration in the housing 12. In this case, the measurement objects 10a, 10b are the items that were most severely damaged among the items contained in the housing 12 loaded in the actual transportation.

[0043] Next, the flow of the vibration process in the above-mentioned embodiment will be described with reference to FIG. In the vibration testing method of this embodiment, an accumulated fatigue determination step is performed in response to the operation of the operator of the vibration device 100 (step S1). In step S1, conditions in line with the test purpose are extracted from the relative acceleration conditions stored in the control device 20 in response to the operation of the operator, and a target accumulated fatigue is calculated from the change over time in the relative acceleration of the extracted conditions. Step S1 is executed by the condition extraction unit 21 in response to the operation of the operator. Furthermore, the operator of the vibration device 100 may select conditions for calculating the target accumulated fatigue according to the test purpose from information associated with the relative acceleration conditions. For example, the operator may select a transportation condition (transportation route) in which the occurrence rate of damage is higher than other transportation conditions (transportation routes), and cause the condition extraction unit 21 to calculate the target accumulated fatigue corresponding to the transportation route.

[0044] In the next step S2, a vibration condition setting process is performed in response to the operation of the operator of the vibration device 100. In step S2, the ranges of vibration frequency and acceleration can be narrowed down to shorten the vibration time based on the conditions extracted in step S1 and the calculated target accumulated fatigue. The operator sets a combination of the ranges of vibration frequency and acceleration so that an efficient vibration test can be performed. Step S2 is executed by the vibration calculation unit 23 in response to the operation of the operator.

[0045] The subsequent steps S3 to S5 correspond to the vibration step described above. In step S3, the housing body 12 is placed on the vibration table 35 of the vibration test device 30, and vibration of the housing body 12 is started under the vibration conditions set in step S2. As described above, the acceleration sensors A1 and A2 are attached to the measurement objects 10a and 10b of the housing body 12, and the housing body 12 is vibrated while monitoring the actual accumulated fatigue based on the relative acceleration of the measurement objects 10a and 10b.

[0046] In the next step S4, it is determined whether the actually measured accumulated fatigue has become equivalent to the target accumulated fatigue. If the actually measured accumulated fatigue has not reached the target accumulated fatigue, the determination in step S4 is repeated while continuing to apply vibration to the accommodation body 12. The determination in step S4 is performed 0.1 to 100 times per second. If it is determined in step S4 that the actually measured accumulated fatigue has become equivalent to the target accumulated fatigue, the process proceeds to step S5, and vibration application by the vibration test device 30 is terminated.

[0047] In the following step S6, it is determined whether or not to perform the next test. If it is determined in step S6 that the next test is to be performed, the process returns to step S1, and the operations from step S1 onwards are repeated. If it is determined in step S6 that the next test is not to be performed, the operation of the vibration generating unit 31 of the vibration testing device 30 is stopped, and this vibration test is terminated. In step S6 of this embodiment, a display is output on the display unit of the vibration device 100, prompting the operator to determine whether or not to continue with the test. In response to this display, the operator operates the input device of the control device 20 to determine whether or not to perform the next test.

[0048] After the above steps S1 to S5, the container 12 to which the vibration has been applied in the vibration application step is checked for the presence or absence of damage to the measurement objects 10a and 10b and the extent of the damage. Such checking is performed visually. For example, the appearance of the packaging container 16, which is the measurement object 10a or 10b, is visually checked for peeling of the label and the presence or absence of cracks in the packaging container 16. In this manner, the vibration testing method of this embodiment can reproduce damage caused by vibration during the transportation of the container 12.

[0049] Although the present invention has been described based on the preferred embodiments, the present invention is not limited to the above-described embodiments. For example, the container 12 in the above-described embodiment is the cardboard box 17 containing a plurality of packaging containers 16, but the container 12 is not limited to this form. The container 12 may contain cushioning material together with the article 11. In the vibration test method of the above embodiment, damage to the appearance of the article 11 (packaging container 16) is checked, but instead, damage to the inside of the article 11 may be checked. For example, if the article 11 is a solid cosmetic such as eye shadow or foundation with a powder cosmetic filled inside a packaging container, damage to the contents of the packaging container (solid cosmetic) may be checked.

[0050] In the above-described embodiment, the accumulated fatigue determination step in the vibration step is executed by the condition extraction unit 21, and the vibration test device 30 in the vibration step is controlled by the vibration calculation unit 23 and the control unit 25, but the present invention is not limited to this embodiment. In this case, part or all of the accumulated fatigue determination step and the vibration step may be performed artificially. Specifically, at least one of the target accumulated fatigue, the vibration time under the assumed equivalent condition, and the vibration time under the accumulated fatigue corresponding condition may be calculated artificially from the measurement results of the relative acceleration, etc.

[0051] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to such examples.

[0052] [Containing Body] A container 12 shown in Fig. 1 and Fig. 2 was prepared. The container 12 was a cardboard box 17, and as shown in Fig. 2, a packaging container 16 consisting of 12 plastic bottles was used. The content volume of the packaging container 16 was 850 mL. The acceleration coefficient α of this packaging container 16 was "2".

[0053] [Vibration test evaluation] Vibration tests were performed under the conditions shown in Table 1 below so that the accumulated fatigue would be constant based on the acceleration or relative acceleration measured by the acceleration sensor.

[0054] Example 1 2, out of a row of three packaging containers 16 lined up in the width direction Y, a first acceleration sensor A1 was attached to packaging container 16a at the center of the width direction Y in one of two rows at the center in the longitudinal direction X, and a second acceleration sensor A2 was attached to packaging container 16b adjacent to packaging container 16a and the peripheral wall of the container 12 in the width direction Y. These two acceleration sensors A1, A2 were attached to the top surfaces (top surfaces of the caps) of packaging containers 16a, 16b.

[0055] In Example 1, a vibration test was performed on the housing 12 under the conditions shown in Table 1 below using a vibration test device 30 shown in Fig. 1. In the vibration test, the relative acceleration of the measurement objects 10a and 10b was monitored, and the vibration time was adjusted so that the actual accumulated fatigue based on the relative acceleration when vibrated under each condition was constant at 3,000,000 (G^2). In other words, the target accumulated fatigue was set to 3,000,000 (G^2).

[0056] The vibration test device 30 was controlled under the vibration conditions shown in Table 1 below. The sine wave test was performed at a constant displacement (peak to peak value (PP value) 1.2 mm) and at the frequency shown in the following Table 1. The PP value is the difference between the positive peak value and the negative peak value of the amplitude. The constant displacement sweep test was carried out at a constant displacement (PP value 1.2 mm) and at the frequency shown in Table 1 below.

[0057] The vibration device 100 used was a vibration test machine (manufactured by IDEXX Corporation, model "BF-50UT"). The acceleration sensor used was an 8-channel small wireless motion recorder (model "MVP-RF8-HC" manufactured by Microstone Corporation). In the vibration test of Example 1, the acceleration in the vertical direction was used as the measurement value of the acceleration sensor. In Example 1, the relative acceleration was calculated from the accelerations of the two packaging containers 16a and 16b, and the actual accumulated fatigue was monitored based on the relative acceleration.

[0058] Comparative Example 1 A vibration test was conducted under the conditions shown in Table 1 using a housing 12 having the same configuration as in Example 1, except that one acceleration sensor was attached to the housing 12 instead of the multiple packaging containers 16a and 16b. The acceleration sensor was attached to the inside of the bottom surface of the housing 12. The vibration time was adjusted so that the accumulated fatigue based on the acceleration of the container 12 was constant at 200,000 (G^2). In this vibration test, the vertical acceleration was used as the measurement value of the acceleration sensor.

[0059] Comparative Example 2 A vibration test was conducted under the conditions shown in Table 1 below using a container 12 having the same configuration as in Example 1, except that instead of multiple packaging containers 16a and 16b, one acceleration sensor was attached to one packaging container 16a inside the container 12. The acceleration sensor was attached to a packaging container in the same arrangement as the packaging container 16a to which the first acceleration sensor A1 of Example 1 was attached. In addition, the vibration time was adjusted so that the accumulated fatigue of the packaging container based on the acceleration was constant at 3,000,000 (G^2). In this vibration test, the vertical acceleration was used as the measurement value of the acceleration sensor.

[0060] [Reference example 1] As Reference Example 1, a transportation test was conducted in which a container 12 having the same configuration as in Example 1 was actually transported over land. In the transportation test, the actual accumulated fatigue based on the relative acceleration corresponding to the measured value in Example 1 was 3,000,000 (G^2), the accumulated fatigue based on the acceleration of the container 12 corresponding to the measured value in Comparative Example 1 was 200,000 (G^2), and the accumulated fatigue based on the acceleration of the packaging container corresponding to the measured value in Comparative Example 2 was 3,000,000 (G^2). Thus, even in the same transportation test or the same vibration test, the acceleration of the packaging container tends to be amplified by the vibration being transmitted through the container 12. As a result, the acceleration of the container 12 and the acceleration of the packaging container differ from each other.

[0061] After each vibration test of Example 1, Comparative Example 1, Comparative Example 2, and Reference Example 1, damages occurred on the packaging container were visually confirmed, and the number of such damages was counted. The damages occurred on the packaging container were holes in the label covering the outer surface of the packaging container. The packaging containers confirmed to have damage in Comparative Examples 1 and 2 and Reference Example 1 were packaging containers with the same arrangement as the measurement objects 10a and 10b of Example 1. Table 1 below shows the number of damages that occurred to the packaging containers.

[0062] [Table 1]

[0063] Based on the SN curve, theoretically, even if the vibration conditions (vibration behavior) are different, if the accumulated fatigue is equivalent, the same degree of damage will occur. According to this theory, the accumulated fatigue applied to the measurement object in the vibration test becomes equivalent to the accumulated fatigue during transportation, so that the damage caused by the vibration during transportation can be reproduced. In addition, theoretically, if the accumulated fatigue is equivalent, the amount of damage caused between different vibration conditions will be about the same, and the amount of damage is less likely to vary between each vibration condition. However, in the vibration tests of Comparative Example 1 and Comparative Example 2, the number of damages varied greatly depending on the vibration conditions. These results indicate that if the accumulated fatigue is based on the acceleration of the container 12 or the packaging container 16, the reproducibility of damage caused by vibrations in the container 12 is low. On the other hand, as is clear from the results in Table 1, in the vibration test of Example 1, the variation in the number of damages was smaller than in Comparative Examples 1 and 2, even when the vibration conditions were changed as shown in Table 1. Furthermore, in the vibration test of Example 1, the number of damages was closer to that of Reference Example 1, which was an actual transportation test, than in Comparative Examples 1 and 2. In other words, it was shown that by making the accumulated fatigue based on the relative acceleration of the packaging containers 16a and 16b, damage caused by vibrations in the container 12 can be reproduced with high reproducibility. [Explanation of symbols]

[0064] 10a, 10b Measurement object 11 Goods 12 Containment Unit 16a,16b Packaging container 17 Cardboard Box 18 Means of transportation 20 Control device 21 Condition extraction part 23 Vibration calculation unit 25 Control Unit 30 Vibration Test Equipment 31 Vibration generating unit 35 Shaking Table 100 Vibration device A1, A2 Acceleration Sensor X Longitudinal direction Y Width direction Z height direction

Claims

1. A method for manufacturing a container for storing a plurality of articles, comprising: a vibration applying step for applying vibration to a container in which a plurality of articles are stored based on accumulated fatigue; The accumulated fatigue is calculated based on a relative acceleration that is an acceleration difference between a plurality of measurement objects in the container, A vibration testing method, wherein the vibration step is a step of applying vibration to a container containing a plurality of items so that the accumulated fatigue of the vibration step is equivalent to the accumulated fatigue based on the relative acceleration measured when the container is in a transport state.

2. The vibration testing method according to claim 1 , wherein the transport state is a land transport state.

3. 3. The vibration testing method according to claim 1, wherein the vibration applying step applies vibration to the container by adjusting a vibration time.

4. 3. The vibration testing method according to claim 1, wherein the plurality of measurement objects are objects housed in the housing so as to be able to come into contact with each other.

5. 3. The vibration testing method according to claim 1, wherein the plurality of measurement objects are items that are most likely to be damaged by the vibrations in the container.

6. 3. The vibration testing method according to claim 1, wherein the container is a cardboard box.

7. A vibration device that applies vibration to a container in which a plurality of items are contained based on accumulated fatigue, The accumulated fatigue is calculated based on a relative acceleration that is an acceleration difference between a plurality of measurement objects in the container, The apparatus includes a condition extraction unit, a vibration calculation unit, and a vibration test device that applies vibration to the container, The condition extraction unit calculates a target accumulated fatigue from a change over time in the relative acceleration measured when a container containing a plurality of items is in a transport state, The vibration calculation unit adjusts the operation of the vibration testing device so that the accumulated fatigue based on the relative acceleration in the housing becomes equivalent to the target accumulated fatigue.

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