Vibration test equipment for analyzing the vibration characteristics of thin-plate and lightweight PCB

Abstract

The present invention relates to a vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB, comprising: an exciter formed to generate vibration; a jig formed at the upper center of the exciter to mount a PCB for analyzing vibration characteristics; a load cell formed between the exciter and the jig to measure the mass of the PCB mounted on the jig; a first measuring unit located on one side of the upper part of the jig and irradiating a laser onto the PCB to measure the amount of vibration and displacement of the PCB; a second measuring unit located on the other side of the upper part of the jig and irradiating a laser onto the jig to measure the amount of vibration and displacement of the jig generated by the exciter; and a control unit that controls the operation of the first measuring unit and the second measuring unit and calculates the amount of deformation and natural frequency of the PCB deformed according to vibration by processing the measured data.

Description

Technology Field

[0001] The present invention relates to a vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB, and more specifically, to a vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB that enables the improvement of durability and quality degradation caused by vibration effects in field environments for PCB substrates used in military applications. Background Technology

[0002] Vibration is a phenomenon in which an object moves repeatedly relative to a reference coordinate system or equilibrium position; such vibrations occur everywhere and have a significant impact on the performance of equipment.

[0003] In particular, for products used for military purposes, vibration is emerging as a critical quality factor regarding whether they operate normally in terms of safety, performance, and field environments, and it is also a factor that significantly affects the durability of components mounted on the circuit boards of such products.

[0004] For example, electrical or electronic devices installed in products used for military purposes—that is, battlefield components—are prone to durability issues. These issues can arise from vibrations or shocks in the field environment, which can cause joints to detach or performance to degrade, preventing normal functional operation.

[0005] Vibration tests performed for this purpose evaluate the durability against vibrations that occur during the operation or transport of the product, and verify the physical damage or operational status of the product before, during, and after the test.

[0006] Conventional vibration tests consist of an exciter that generates vibration, a test table for placing the PCB, and an acceleration sensor attached to the PCB that generates an electrical signal in proportion to the physical force or acceleration it receives.

[0007] When measuring with an acceleration sensor, it must be directly attached to the PCB. Therefore, unless the mass of the PCB is large relative to the mass of the acceleration sensor, there was a problem in that incorrect vibration characteristic results were obtained due to deformation of the PCB and changes in resonance frequency caused by the mass of the acceleration sensor, and the durability of the PCB was improved based on distorted information.

[0008] In addition, since the measurement result is acceleration, there was a problem in that an integrator had to be applied to calculate the displacement, which is the actual result to be verified, separately using a formula. Also, in the low frequency range, acceleration is proportional to the square of the frequency value, so it is difficult to measure, and there was a problem in that it is difficult to measure small displacements.

[0009] In order to solve the weight problem of such acceleration sensors, a technology for measuring displacement using strain gauges was applied, but in this case, the bridge circuit must be attached to the PCB, and if the circuit is attached incorrectly, a distorted result is output. Furthermore, there was a problem in that it could not be applied in cases where there is no flat surface, such as on a PCB, where various components protrude for circuit configuration. Prior art literature

[0010] Korean Patent Publication No. 10-2008-0113050 The problem to be solved

[0011] The objective of the present invention, which aims to solve the aforementioned problems, is to provide a vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB that can prevent data distortion caused by changes in the physical characteristics of the PCB by conducting a vibration test without direct contact with the PCB.

[0012] In addition, another objective of the present invention is to provide a vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB, which improves measurement accuracy by measuring minute displacements when measuring deformation and resonance frequency of the PCB due to vibration, thereby enabling easy verification of the structural characteristics of the PCB.

[0013] In addition, another objective of the present invention is to provide a vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB, which solves the problem of having to stop the equipment and move or add sensors to check the characteristics of areas other than the attachment location when attaching multiple sensors to a PCB for testing purposes to verify and improve vibration propagation characteristics. means of solving the problem

[0014] A vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention for solving the above problem comprises: an exciter formed to generate vibration; a jig formed at the upper center of the exciter to mount a PCB for analyzing vibration characteristics; a load cell formed between the exciter and the jig to measure the mass of the PCB mounted on the jig; a first measuring unit located on one side of the upper part of the jig and irradiating a laser onto the PCB to measure the amount of vibration and displacement of the PCB; a second measuring unit located on the other side of the upper part of the jig and irradiating a laser onto the jig to measure the amount of vibration and displacement of the jig generated by the exciter; and a control unit that controls the operation of the first measuring unit and the second measuring unit and calculates the amount of deformation and natural frequency of the PCB deformed according to vibration by performing calculations on the measured data.

[0015] In addition, the upper center of the jig of the vibration test device for analyzing the vibration characteristics of the thin-plate lightweight PCB of the present invention further includes a plurality of support pins protruding upward to flatly support the lower surface of the PCB.

[0016] In addition, the vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB of the present invention is characterized by further including a frame formed spaced apart from the edge of the exciter so as not to come into contact with the exciter, and a plurality of variable bands formed on the upper part of the frame and configured to adjust the position where the laser is irradiated by varying the positions of the first measuring part and the second measuring part in three dimensions through a multi-joint link.

[0017] In addition, the first and second measuring units of the vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention are characterized by comprising: a housing having one open side; a displacement sensor formed on one side of the housing and configured to irradiate a laser toward the PCB or the jig and receive the reflected laser; a camera formed on the other side of the housing that captures the position of the laser irradiated from the displacement sensor to generate image information of the measurement area; and an angle adjuster formed on the rear of the camera that corrects the angle at which the camera is photographed to match the laser irradiated by the displacement sensor.

[0018] In addition, the first and second measuring units of the vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB of the present invention can generate image information by photographing the location irradiated by a laser to measure the amount of vibration using a camera and then storing the measurement location, so that the amount of vibration and displacement can be measured at the same measurement location based on the image information when performing repeated tests or replacing the PCB.

[0019] In addition, the control unit of the vibration test device for analyzing the vibration characteristics of the thin-plate lightweight PCB of the present invention is characterized by converting the vibration amount measured by the first measurement unit and the second measurement unit into a frequency band through FFT conversion, synchronizing the two data at the same time, and then confirming the natural frequency band transmitted to the PCB through the superposition of the two data.

[0020] In addition, the control unit of the vibration test device for analyzing the vibration characteristics of the thin-plate lightweight PCB of the present invention is characterized by calculating the actual deformation amount of the PCB using the difference value of the displacement of the PCB measured in the first measurement unit based on the displacement of the jig measured in the second measurement unit. Effects of the invention

[0021] As described above, the vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention can be applied to lightweight, thin products rather than attachments with a large mass relative to acceleration, thereby enabling accurate result values ​​to be obtained without deformation or changes in resonance frequency caused by the mass of the sensor itself.

[0022] In addition, according to the vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention, it is not necessary to consider changes in resonance frequency caused by contact, and since it is directly measured regardless of the low or high frequency range, it has the effect of enabling measurement of minute displacements.

[0023] In addition, according to the vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention, since the result value does not vary depending on the precision of circuit attachment, there is an effect of obtaining a constant result value.

[0024] In addition, according to the vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention, there is an effect that enables measurement even when there is no sensor attachment surface because protrusions caused by components, such as PCB circuits, are not uniform.

[0025] In addition, according to the vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention, since the measurement is not performed by attaching it to the PCB, there is an effect of being able to vary the measurement position during the test. Brief explanation of the drawing

[0026] FIG. 1 is a schematic diagram showing the overall configuration of a vibration test apparatus for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention. FIG. 2 is a perspective view showing the overall shape of a vibration test apparatus for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention. FIG. 3 is a front view showing the front view of a vibration test apparatus for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention. FIG. 4 is an enlarged perspective view showing a PCB mounted on a jig of a vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention. FIG. 5 is an enlarged perspective view showing the structure of a measurement unit of a vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention. Specific details for implementing the invention

[0027] The specific features and advantages of the present invention will be described in detail below with reference to the accompanying drawings. Prior to this, if it is determined that a detailed description of the functions and configurations related to the present invention may unnecessarily obscure the essence of the invention, such detailed description will be omitted.

[0028] The present invention relates to a vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB, and more specifically, to a vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB that enables the improvement of durability and quality degradation caused by vibration effects in field environments for PCB substrates used in military applications.

[0029] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0030] FIG. 1 is a schematic diagram showing the overall configuration of a vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention; FIG. 2 is a perspective view showing the overall shape of a vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention; FIG. 3 is a front view showing the appearance of a vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention as viewed from the front; FIG. 4 is an enlarged perspective view showing the appearance of a PCB mounted on a jig of a vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention; and FIG. 5 is an enlarged perspective view showing the structure of a measurement unit of a vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention.

[0031] As illustrated in FIGS. 1 to 5, a vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB (10) according to the present invention comprises: an exciter (200) formed to generate vibration; a jig (220) formed at the upper center of the exciter (200) to mount a PCB (10) for analyzing vibration characteristics; a load cell (210) formed between the exciter (200) and the jig (220) to measure the mass of the PCB (10) mounted on the jig (220); a first measuring unit (300) located on one side of the upper part of the jig (220) to irradiate a laser onto the PCB (10) to measure the amount of vibration and displacement of the PCB (10); and a device located on the other side of the upper part of the jig (220) to irradiate a laser onto the jig (220) to measure the amount of vibration and displacement of the jig (220) generated by the exciter (200). It is characterized by including a second measuring unit (400) and a control unit (500) that controls the operation of the first measuring unit (300) and the second measuring unit (400), calculates the deformation amount and natural frequency of the PCB (10) as it deforms according to vibration by calculating the measured data.

[0032] In addition, the upper center of the jig (220) is further characterized by including a plurality of support pins (221) that protrude upward to support the lower surface of the PCB (10) flat.

[0033] In addition, it is characterized by further including a frame (100) formed spaced apart from the edge of the exciter (200) so as not to come into contact with the exciter (200), and a plurality of variable bands (110) formed on the upper part of the frame (100) and formed to adjust the position where the laser is irradiated by varying the position of the first measuring part (300) and the second measuring part (400) in three dimensions through a multi-joint link.

[0034] The exciter (200) is configured to generate vibrations by forcibly shaking the product to perform a vibration test during the product development stage, and is controlled by the control unit (500) to generate vibrations of a set frequency.

[0035] At this time, the exciter (200) may be configured as a mechanical, electric, or electro-hydraulic type, but preferably, it is preferred to be an electric type that generates vibration using electromagnetic induction, and the control unit (500) can control the exciter (200) in detail through electric control.

[0036] The exciter (200) is formed in a cylindrical shape so that a coil must be wound inside, and a flat disc is formed on the upper surface so that the jig (220) can be seated on it.

[0037] In addition, since the exciter (200) is formed in a cylindrical shape, a base (230) is formed at the bottom of the exciter (200) so that the exciter (200) can be supported on the ground or a table.

[0038] The base (230) is formed with an open top in a U-shape so that the exciter (200) can be inserted from the top, and the bottom surface is formed flat so that it is in close contact with the ground or table to transmit the load of the exciter (200) and maintain a stable position.

[0039] At this time, connecting shafts are provided on both sides of the exciter (200), so that the connecting shafts are inserted into the open inner surface of the base (230) and can be connected in a spaced-away state from the lower surface of the base (230), thereby allowing the base (230) to stably support the exciter (200) and prevent vibrations generated from the exciter (200) from being suppressed by the base (230).

[0040] The upper surface of the exciter (200) is formed in the shape of a disc, and a jig (220) for mounting a PCB (10), which is a vibration test product, is formed in the center of the upper surface. The jig (220) is formed to transmit vibrations generated from the exciter (200) to the PCB (10) so that the PCB (10) can vibrate.

[0041] At this time, in order to analyze the vibration characteristics of the PCB (10), a load cell (210) is formed between the jig (220) and the exciter (200) so as to measure the weight of the PCB (10) mounted on the jig (220), and the control unit (500) can determine the mass of the PCB (10) mounted on the jig (220) through the load cell (210).

[0042] In addition, the upper surface of the jig (220) is formed with a number of conical support pins (221) at regular intervals so as to stably support the lower surface of the PCB (10), and the support pins (221) can be stably mounted by contacting the lower surface of the PCB (10) in multiple numbers.

[0043] When the support pin (221) is formed in a conical shape, the lower part that contacts the jig (220) is formed with a wide diameter and the upper part is formed with a narrow diameter. Since the lower part is formed wider than the upper part, shaking of the upper part of the support pin (221) can be suppressed when vibration occurs, thereby enabling stable support of the PCB (10).

[0044] If the support pin (221) is not formed in a conical shape, when the support pin (221) is vibrated by the exciter (200) and resonance occurs due to the natural frequency, the upper part of the support pin (221) may shake significantly, potentially damaging the PCB (10) or distorting the input vibration transmitted to the PCB (10). Therefore, it is preferable for the support pin (221) to be formed in a conical shape.

[0045] The first measuring unit (300) and the second measuring unit (400) are formed to measure vibration amount and displacement by irradiating a laser downward after being spaced upward from the jig (220).

[0046] The first measuring unit (300) is used to measure the vibration state of the PCB (10) and the displacement caused by the vibration by irradiating a laser onto the upper surface of the PCB (10), and the first measuring unit (300) may be configured to measure at different parts of the PCB (10) after forming multiple units.

[0047] The second measuring unit (400) is used to irradiate a laser onto the upper surface of the jig (220) on which the PCB (10) is mounted to determine the vibration state transmitted to the jig (220) through the exciter (200) and the displacement deformed by the vibration, and the control unit (500) can determine the state in which the jig (220) is vibrating through the measurement data of the second measuring unit (400) and adjust the output of the exciter (200).

[0048] That is, the first measuring unit (300) measures the amount of vibration and displacement of the PCB (10) that is the subject of the vibration test, and the second measuring unit (400) measures the amount of vibration and displacement of the jig (220) to determine the vibration information output from the exciter (200) and to use as reference data to determine the actual amount of vibration and displacement transmitted to the PCB (10).

[0049] In the case of conventional acceleration sensors, it was difficult to measure vibrations generated by high frequency affecting the PCB (10), and it was not easy to attach the PCB (10) as the shape of the PCB (10) had many electronic components attached to it, and even if it was attached, there was a problem that distorted data was measured due to deformation of the PCB (10) caused by the mass of the acceleration sensor and changes in natural frequency.

[0050] However, the first measuring unit (300) and the second measuring unit (400) are configured to measure the amount of vibration by irradiating a laser, so the amount of vibration of the PCB (10) and the jig (220) is measured in a non-contact manner, making test preparation simple, and since it does not directly affect the PCB (10), it is possible to prevent data distortion.

[0051] At this time, the sampling frequency of the laser irradiated from the first measuring unit (300) and the second measuring unit (400) is formed to have a higher period than the vibration frequency output from the exciter (200), so that the amplitude generated in the PCB (10) or jig (220) can be accurately and repeatedly measured.

[0052] In addition, the first measuring part (300) and the second measuring part (400) are positioned spaced apart on the upper part of the jig (220), and a frame (100) and a variable base (110) are additionally formed so that the measuring position can be freely varied.

[0053] The frame (100) is formed in a cylindrical shape and has an upper and lower opening in the center so that an exciter (200) and a base (230) can be inserted, thereby preventing the exciter (200) and the base (230) from coming into direct contact with the frame (100).

[0054] At this time, the frame (100) does not necessarily have to be formed in a cylindrical shape, and may be formed to be attached to a wall or ceiling in the form of a bracket to support the variable support (110), and the present invention will be described based on a shape formed in a cylindrical shape.

[0055] The variable member (110) is formed as a multi-joint link formed to be able to rotate and pivot in three dimensions through a plurality of links and joints, and one end is fixed by being coupled to the upper surface of the frame (100), and the other end is formed so that a first measuring part (300) or a second measuring part (400) can be coupled.

[0056] At this time, it is preferable that a variable stand (110) be formed according to the number of the first measuring section (300) or the second measuring section (400), and through the variable stand (110), the first measuring section (300) and the second measuring section (400) can be positioned spaced apart on the upper part of the jig (220), and the measuring position can be freely varied.

[0057] If necessary, the variable unit (110) can be formed as a multi-axis robot so that the position of the first measuring unit (300) or the second measuring unit (400) can be automatically varied by the control unit (500) to diversify the measurement position, thereby enabling vibration testing while changing the vibration measurement position, thus enabling automated testing.

[0058] In addition, the first measuring unit (300) and the second measuring unit (400) can generate image information by capturing the location irradiated by a laser with a camera (310, 410) to measure the amount of vibration, and then store the measurement location, so that the amount of vibration and displacement can be measured at the same measurement location based on the image information when performing repeated tests or replacing the PCB (10).

[0059] Additionally, the first measuring unit (300) and the second measuring unit (400) are characterized by comprising a housing (330, 430) having one side open, a displacement sensor (320, 420) formed on one side of the housing (330, 430) and formed to irradiate a laser toward a PCB (10) or jig (220) and receive a reflected laser, a camera (310, 410) formed on the other side of the housing (330, 430) and capturing the position of the laser irradiated from the displacement sensor (320, 420) to generate image information of the measurement area, and an angle adjustment bracket (311, 411) formed on the rear of the camera (310, 410) and correcting the angle at which the camera (310, 410) is photographed to match the laser irradiated by the displacement sensor (320, 420).

[0060] The first measuring unit (300) and the second measuring unit (400) are both configured with the same structure, but differ only in that the objects being measured are divided into the PCB (10) and the jig (220), respectively, and in the present invention, the configuration will be described based on the first measuring unit (300).

[0061] The first housing (330) is formed in a rectangular shape with one side open and is used to mount and protect the first camera (310), the first angle adjustment rod (311), and the first displacement sensor (320) inside.

[0062] At this time, the other side of the first housing (330) is combined with the variable base (110), so that the position of the first housing (330) can be varied and fixed according to the position of the variable base (110), and through this, the measurement position of the first camera (310) and the first displacement sensor (320) located inside the first housing (330) can be varied.

[0063] The first displacement sensor (320) is formed on one side of the opening of the first housing (330) and is configured to irradiate a laser onto the PCB (10) and receive the reflected laser, and is capable of measuring data to determine the amplitude, period, and displacement of the PCB (10) of the vibration generated from the deformation of the PCB (10).

[0064] The first camera (310) is formed on the other side of the first housing (330) and is used to generate image information so that the position currently being measured by the displacement sensor can be visually confirmed by photographing the PCB (10) centered on the position where the laser is being irradiated.

[0065] At this time, the control unit (500) is configured to separately store image information generated through the first camera (310), and can control the laser to be irradiated at the same location when conducting a repeated test based on the stored image information or when testing the same part by replacing another PCB (10).

[0066] The first angle adjustment member (311) is formed on the rear of the first camera (310) and is configured to be coupled to the first housing (330) by a pivot axis, so that the shooting angle of the first camera (310) can be adjusted according to the control command of the control unit (500).

[0067] Typically, the first displacement sensor (320) to which a laser is irradiated is configured so that only the position changes in two-dimensional coordinates while the measured height is maintained constant, so the first camera (310) is configured to photograph the PCB (10) centered on the point where the first displacement sensor (320) irradiates the PCB (10).

[0068] To this end, the first camera (310) is formed in a rotated state toward the first displacement sensor (320), and when the height of the first displacement sensor (320) changes, the angle adjustment member adjusts the rotation angle so that the center of the image captured by the first camera (310) can be aligned with the point where the laser is irradiated.

[0069] In addition, the second displacement sensor (420), second camera (410), and second angle adjustment rod (411) formed in the second measuring unit (400) are formed in the second housing (440), differing only in that the measurement target is a jig (220), and other functions and configurations are identical to each other, so they are omitted.

[0070] The control unit (500) is formed to calculate vibration and displacement data of the PCB (10) and jig (220) measured by the first measurement unit (300) and the second measurement unit (400) and output amplitude, period, and displacement, and includes a high-speed calculator for real-time measurement, an input / output terminal for signal input / output, and a synchronization module for synchronizing the signals and time of the first measurement unit (300) and the second measurement unit (400).

[0071] Time synchronization between the first measuring unit (300) and the second measuring unit (400) is configured such that accurate time is synchronized between the first measuring unit (300) and the second measuring unit (400) using a wired electrical signal, converted through an A / D converter, and then transmitted to the output unit (600) so that data can be checked on the display formed in the output unit (600).

[0072] The output unit (600) is configured to output data calculated by the control unit (500) to a display for real-time verification, and the results measured according to the synchronized signal from the control unit (500) can be visually verified, and the output information can be stored in memory.

[0073] In addition, the control unit (500) is characterized by converting the vibration amount measured by the first measurement unit (300) and the second measurement unit (400) into a frequency band through FFT conversion, synchronizing the two data at the same time, and then confirming the unique frequency band transmitted to the PCB (10) through the superposition of the two data.

[0074] In addition, the control unit (500) is characterized by calculating the actual deformation amount of the PCB (10) using the displacement difference value of the PCB (10) measured in the first measurement unit (300) based on the displacement of the jig (220) measured in the second measurement unit (400).

[0075] Since the PCB (10) is seated on the upper part of the jig (220), the amount of displacement caused by the jig (220) vibrating and deforming can be measured in the same way on the PCB (10), making it difficult to accurately measure the displacement caused by the deformation of the PCB (10).

[0076] To this end, the first measuring unit (300) measures the amount of vibration and displacement of the PCB (10), and the second measuring unit (400) measures the amount of vibration and displacement of the jig (220), and then measures the amount of displacement of the actual PCB (10) by using the difference between the displacement generated by the jig (220) and the displacement generated by the PCB (10).

[0077] The control unit (500) can calculate the natural frequency of the PCB (10) and the amount of deformation caused by vibration using data measured by the first measurement unit (300) and the second measurement unit (400).

[0078] When the exciter (200) is operated, the first measuring unit (300) irradiates a laser onto the PCB (10) to measure the amount of vibration and displacement, and at this time, the first displacement sensor (320) of the first measuring unit (300) can output the amount of change in voltage as follows.

[0079]

[0080] (a) Graph showing the amount of vibration of the PCB (10)

[0081] The above A(VT) represents the amount of change in voltage relative to time, where Low data measured by the first measuring unit (300) is input to the control unit (500).

[0082] In addition, the second measuring unit (400) measures the amount of vibration and displacement measured by irradiating a laser onto the jig (220), and at this time, the second displacement sensor (420) of the second measuring unit (400) can output the amount of change in voltage as follows.

[0083]

[0084] (b) Graph showing the amount of vibration of the jig (220)

[0085] The above B(VT) represents the amount of change in voltage relative to time, where Low data measured by the second measuring unit (400) is input to the control unit (500).

[0086] The control unit (500) performs an FFT conversion so that the amount of voltage change can be verified as the amount of current change according to the frequency band, and the data measured by the first measurement unit (300) is converted as follows.

[0087]

[0088] (c) Graph showing the vibration amount of PCB (10) in frequency bands through FFT transformation

[0089] The above FFT A(Fq-Amp) represents the amount of current change according to the frequency band by performing an FFT transformation on the data measured by the first measurement unit (300).

[0090] In addition, the control unit (500) performs an FFT conversion so that the amount of voltage change can be verified as the amount of current change according to the frequency band, and the data measured by the second measurement unit (400) is converted as follows.

[0091]

[0092] (d) Graph showing the vibration amount of the jig (220) in frequency bands through FFT transformation

[0093] The above FFT B (Fq-Amp) represents the amount of current change according to the frequency band by performing an FFT transformation on the data measured by the second measurement unit (400).

[0094] By converting the data measured by the first measurement unit (300) and the second measurement unit (400) into FFT and displaying it as a frequency band, it becomes possible to determine in which frequency band vibration occurs in the PCB (10) and the jig (220).

[0095] The control unit (500) synchronizes the data of the first measurement unit (300), which is converted into a current change amount according to the frequency band through FFT conversion, and the data of the second measurement unit (400) at the same time, and then outputs the difference value of the current amount of the overlapping frequency band as follows.

[0096]

[0097] (e) Graph showing the current difference between the FFT-transformed PCB and the jig in the same frequency band

[0098] That is, the control unit (500) outputs the data measured by the first measurement unit (300) and the second measurement unit (400) as a frequency-ampere graph through FFT conversion, and after superimposing the two graphs, it becomes possible to calculate the difference in current amount in the same frequency band.

[0099] At this time, by subtracting the data value measured by the second measurement unit (400) from the data value measured by the first measurement unit (300) based on the same frequency band, it is possible to detect vibrations occurring in the actual PCB (10) and determine the amount of displacement.

[0100] That is, the data measured by the first measurement unit (300) and the second measurement unit (400) is converted into an FFT and displayed in a frequency band, and by subtracting the current amount of the jig (220) from the current amount of the PCB (10) appearing in the same frequency band, the actual displacement amount of the PCB (10) can be determined.

[0101] The vibration output from the exciter (200) is transmitted through the jig (220), and since the displacement generated as the jig (220) vibrates affects the PCB (10) in the same way, if the amount of current generated in the same frequency band of the two graphs is the same, it can be determined that the same value is output to the PCB (10) as the jig (220) deforms.

[0102] For example, in graph (c), it can be seen that the amount of current changes at 5Hz, 50Hz, and 250Hz, while in graph (d), the amount of current changes at 50Hz and 230Hz.

[0103] If the current amount of graph (d) is subtracted from graph (c) based on the frequency band where the current amount changes significantly, it can be expressed as graph (e). In this case, since there is no current change amount of 5 Hz in graph (d), the current amount of graph (c) is output as is, and in the case of 50 Hz, since the same current amount exists in both graphs, it becomes 0 and is eliminated.

[0104] In addition, although the bands of 250Hz and 230Hz do not actually match, they can be determined to be the same frequency because their frequency bands are nearly similar, and by subtracting the current amount of 230Hz from the current amount of 250Hz, only the difference value can be output as shown in graph (e).

[0105] At this time, since the displacement of the PCB (10) being measured is to be measured, the frequency band is output based on 250Hz of graph (c).

[0106] As a result, the part where the current changes significantly for each frequency band output in the graph (e) can be determined as the actual deformation of the PCB (10), and the control unit (500) can display the actual deformation amount by converting the current amount into mm and outputting it.

[0107] In addition, the frequency band where deformation of the PCB (10) occurs can be determined to be the natural frequency at which resonance of the PCB (10) can occur.

[0108]

[0109] (f) A graph showing the signals of the first measuring unit (300) and the second measuring unit (400) synchronized

[0110] In addition, the control unit (500) can generate a trigger signal to indicate the start of the test, thereby inducing the first measurement unit (300) and the second measurement unit (400) to start the measurement simultaneously. As the measurement starts simultaneously, the two measured data are synchronized, and the actual deformation amount of the PCB (10) can be output to the output unit (600) through FFT conversion in real time.

[0111] As described above, according to the vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB according to the present invention, it is possible to apply it to lightweight thin products rather than attachments with a large mass relative to acceleration, thereby obtaining accurate results without deformation or changes in resonance frequency caused by the mass of the sensor itself, and it is not necessary to consider changes in resonance frequency caused by contact. Since it measures directly regardless of the low or high frequency range, it is possible to measure minute displacements. Since the result value does not change depending on the precision of the circuit attachment, a constant result value can be obtained. It is also possible to measure even when there is no sensor attachment surface because protrusions caused by components, such as PCB circuits, are not uniform. Furthermore, since it is not measured by attaching to the PCB, it has the effect of allowing the measurement position to be varied in various ways during the test.

[0112] As described above, although the present invention has been explained with reference to preferred embodiments, those skilled in the art may implement the present invention with various modifications or variations without departing from the technical spirit and scope described in the claims of the present invention. Accordingly, the scope of the present invention should be interpreted by the claims described to include such many variations. Explanation of the symbols

[0113] 10 : PCB 100 : Frame 110 : Variable band 200 : Exciter 210 : Load cell 220 : Jig 221 : Support pin 230 : Base 300: First measuring unit 310: First camera 311: First angle adjustment bracket 320: First displacement sensor 330 : 1st housing 400 : 2nd measuring part 410: Second camera 411: Second angle adjuster 420 : Second displacement sensor 430 : Second housing 500: Control unit 600: Output unit

Claims

Claim 1 The apparatus comprises: an exciter formed to generate vibration; a jig formed at the upper center of the exciter to mount a PCB for analyzing vibration characteristics; a load cell formed between the exciter and the jig to measure the mass of the PCB mounted on the jig; a first measuring unit located on one side of the upper part of the jig and irradiating a laser onto the PCB to measure the amount of vibration and displacement of the PCB; a second measuring unit located on the other side of the upper part of the jig and irradiating a laser onto the jig to measure the amount of vibration and displacement of the jig generated by the exciter; and a control unit that controls the operation of the first measuring unit and the second measuring unit and calculates the amount of deformation and natural frequency of the PCB deformed according to vibration by processing the measured data; wherein the first measuring unit and the second measuring unit comprise a housing having one side open; a displacement sensor formed on one side of the housing and configured to irradiate a laser toward the PCB or the jig and receive the reflected laser; and a displacement sensor formed on the other side of the housing and It comprises: a camera that captures the position of a laser irradiated from a displacement sensor to generate image information of the measurement area; and an angle adjustment stand formed on the rear of the camera to correct the angle at which the camera captures the image to match the laser irradiated by the displacement sensor; wherein the first measurement unit and the second measurement unit can capture the position irradiated by a laser with a camera to generate image information and then store the measurement position, so that when performing repeated tests or replacing the PCB, the amount of vibration and displacement can be measured at the same measurement position based on the image information; and a plurality of support pins protruding upwardly at the upper center of the jig to flatly support the lower surface of the PCB;A vibration testing device for analyzing the vibration characteristics of a thin-plate lightweight PCB, further comprising, wherein the support pin is formed in a conical shape with a wide bottom diameter and a narrow top diameter, so as to prevent damage to the PCB or distortion of input vibrations transmitted to the PCB by shaking the top when vibration occurs. Claim 2 delete Claim 3 A vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB, further comprising: a frame formed spaced apart from the edge of the exciter so as not to come into contact with the exciter in claim 1; and a plurality of variable bands formed on the upper part of the frame and configured to adjust the position where the laser is irradiated by varying the positions of the first measuring part and the second measuring part in three dimensions through a multi-joint link. Claim 4 delete Claim 5 delete Claim 6 A vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB, wherein, in claim 1, the control unit converts the vibration amount measured by the first measuring unit and the second measuring unit into a frequency band through FFT conversion, synchronizes the two data at the same time, and then confirms the natural frequency band transmitted to the PCB through the superposition of the two data. Claim 7 A vibration test device for analyzing the vibration characteristics of a thin-plate lightweight PCB, wherein, in claim 1, the control unit calculates the actual deformation amount of the PCB using the displacement difference value of the PCB measured in the first measuring unit based on the displacement of the jig measured in the second measuring unit.

Images