Intensity measuring device, intensity measuring system, and intensity measuring method

Abstract

To efficiently measure intensity of shot treatment.SOLUTION: An intensity measuring device 30 is connected to a sensor device for outputting a signal waveform related to an elastic wave generated by shot treatment, and measures intensity of shot treatment on the basis of the signal waveform. The intensity measuring device 30 includes: a waveform acquisition part 31 for acquiring the signal waveform from the sensor device; a time-series data generation part 32 for generating time-series data of an effective value of the signal waveform; an average value acquisition part 33 for determining the average value of the effective value in a predetermined time length, on the basis of the time-series data; and an intensity acquisition part 34 for determining the intensity of the shot treatment, on the basis of the average value of the effective value.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to an intensity measurement device, an intensity measurement system, and an intensity measurement method.

Background Art

[0002] In shot processing such as shot blasting or shot peening, a shot medium is projected onto an object to be processed. When performing shot processing, it is required to collide the shot medium with the object to be processed at an appropriate strength so that the object to be processed reaches an appropriate processing state according to its use.

[0003] Generally, intensity is used as an index to quantitatively represent the strength of shot processing. Intensity is equivalent to the arc height corresponding to the arc height when a test piece is shot-processed over an arbitrary period of time, the arc height (the amount of warping of the test piece) is measured, a peening time-arc height saturation curve is created, and the increase rate of the arc height read from the saturation curve is within 10%. Patent Document 1 describes a metal plate used as a test piece for measuring intensity. The metal plate for intensity measurement is also called an Almen strip.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Summary of the Invention

Problems to be Solved by the Invention

[0005] In order to obtain the arc height saturation curve, it is necessary to project the shot medium onto a plurality of Almen strips to measure the arc height. Since the Almen strips cannot be reused and waste is generated, it is not preferable from the viewpoints of cost and environmental load. Further, in order to measure the arc height value using a micro gauge and obtain the arc height saturation curve, a great deal of labor is required, so there is a problem that it takes time to measure the intensity.

[0006] Therefore, an object of the present disclosure is to provide an intensity measurement device, an intensity measurement system, and an intensity measurement method capable of efficiently measuring intensity.

Means for Solving the Problems

[0007] The intensity measurement device according to one aspect is connected to a sensor device that outputs a signal waveform related to the elastic wave generated by the shot process, and measures the intensity of the shot process based on the signal waveform. This intensity measurement device includes a waveform acquisition unit, a time series data generation unit, an average value acquisition unit, and an intensity acquisition unit. The waveform acquisition unit acquires a signal waveform from the sensor device. The time series data generation unit generates time series data of the effective value of the signal waveform. The average value acquisition unit obtains the average value of the effective value over a predetermined time length based on the time series data. The intensity acquisition unit obtains the intensity of the shot process based on the average value of the effective value.

Effects of the Invention

[0008] According to various aspects of the present disclosure, intensity can be efficiently measured.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

[0010] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference numerals, and overlapping descriptions are not repeated. The dimensional ratios in the drawings do not necessarily match those in the description.

[0011] [Examples of Embodiments of the Present Disclosure] FIG. 1 is a diagram schematically showing a shot processing system according to an embodiment. The shot processing system 1 shown in FIG. 1 projects a shot medium under set projection conditions. In this specification, the process of projecting a shot medium from a shot processing device is referred to as shot processing. Shot processing includes shot blasting for the purpose of scale removal, burr removal, surface roughness adjustment, etc., and shot peening for the purpose of imparting compressive residual stress to an object to be processed.

[0012] As shown in FIG. 1, the shot peening system 1 includes a shot peening apparatus 10, a sensor device 20, and an intensity measurement device 30. The shot peening apparatus 10 processes the surface of the object to be processed by projecting a shot medium onto the object to be processed and causing the shot medium to collide with the object to be processed. For example, the shot peening apparatus 10 is a shot peening device that applies compressive residual stress to the surface of the object to be processed. Examples of the object to be processed on which shot peening is performed by the shot peening apparatus 10 include automotive parts such as cylinder heads and crankshafts, gears, molds, etc., but the object to be processed is not limited thereto. By applying compressive residual stress to the surface of the object to be processed by shot peening, the fatigue characteristics of the object to be processed are improved.

[0013] The compressive residual stress to be applied to the object to be processed is determined according to the use of the object to be processed. In order to apply the required compressive residual stress to the object to be processed, it is required to perform shot peening on the object to be processed with an appropriate strength. Generally, intensity is used as an index for quantitatively representing the strength of shot peening. Intensity is defined as follows: After performing shot peening on a test piece over an arbitrary period of time, an arc height value is measured to create a peening time-arc height saturation curve, and it corresponds to the arc height at the point when the increase rate of the arc height read from the saturation curve is within 10%. The calculation method of intensity is defined in SAE standard J443 (2010).

[0014] The shot peening device 10 may be a pneumatic type that injects the shot medium as a solid-gas two-phase flow together with compressed air, or may be a centrifugal type that projects the shot medium by the centrifugal force generated by the rotation of an impeller, which is a type of impeller. The shot peening device 10 shown in FIG. 1 is a direct-pressure type shot peening device. Note that the shot peening device 10 may be a suction type or a gravity type shot peening device. Further, the shot peening device 10 may be a wet shot peening device. The material of the shot medium 2 projected onto the object to be processed may be, for example, an iron-based metal such as steel or iron, a non-ferrous metal such as stainless steel, or a non-metal such as glass or zirconia. The shape of the shot medium 2 may be spherical, or may be a rounded corner of a granular material (so-called cut wire) obtained by cutting a drawn wire to a predetermined length. As the shot medium 2, for example, steel balls are used. Note that the material, shape, and particle size of the shot medium 2 are appropriately selected according to the compressive residual stress to be imparted to the object to be processed.

[0015] As shown in FIG. 1, the shot peening device 10 includes a shot medium tank 11, a shot medium supply device 12, a pressurizing tank 13, a compressor 14, a nozzle 15, and a control device 16. The shot medium tank 11 stores the shot medium 2. The shot medium tank 11 is connected to the pressurizing tank 13 via the shot medium supply device 12. A poppet valve 64 that can be opened and closed is provided between the shot medium supply device 12 and the pressurizing tank 13. When the poppet valve 64 is opened, the shot medium 2 stored inside the shot medium tank 11 is supplied to the pressurizing tank 13 through the shot medium supply device 12.

[0016] Compressor 14 generates compressed air and supplies the compressed air to the pressurized tank 13 and the nozzle 15. One end of the pipe 61 is connected to the compressor 14. The other end of the pipe 61 is connected to the pipe 63 described later. A pipe 62 branches off from a position between one end and the other end of the pipe 61. The pipe 62 is connected to the air inlet 13A of the pressurized tank 13. An air flow rate adjustment valve 68 is provided in the pipe 62. The air flow rate adjustment valve 68 adjusts the flow rate of the compressed air flowing through the pipe 62. When the air flow rate adjustment valve 68 is opened, the compressed air from the compressor 14 is supplied to the pressurized tank 13 via the pipes 61 and 62. By supplying the compressed air from the compressor 14 to the pressurized tank 13, the inside of the pressurized tank 13 is pressurized.

[0017] The pressurized tank 13 has a shot outlet 13B for discharging the shot medium 2. An openable and closable cut gate 60 is provided at the shot outlet 13B. A pipe 63 is connected to the shot outlet 13B via the cut gate 60. A shot amount adjustment valve 65 for adjusting the amount of the shot medium 2 ejected from the nozzle 15 is provided in the pipe 63. The other end of the pipe 61 is connected to the pipe 63. The connection portion between the pipe 61 and the pipe 63 constitutes a mixing portion 25A where the shot medium 2 supplied from the pressurized tank 13 and the compressed air supplied from the compressor 14 are mixed. This mixing portion 25A is located on the downstream side of the branch portion 25B where the pipe 62 branches off from the pipe 61 in the flow direction of the compressed air.

[0018] An air flow rate adjustment valve 66 is provided at a position between the mixing portion 25A and the branch portion 25B in the pipe 61. The air flow rate adjustment valve 66 adjusts the flow rate of the compressed air supplied from the compressor 14 to the nozzle 15. The compressed air whose flow rate is adjusted by the air flow rate adjustment valve 66 is mixed with the shot medium 2 supplied from the pressurized tank 13 in the mixing portion 25A and sent to the nozzle 15.

[0019] The nozzle 15 is provided at the tip of the pipe 63 and injects the shot medium 2 supplied from the pressurized tank 13 as a solid-gas two-phase flow together with compressed air. The nozzle 15 is disposed inside the cabinet 70. The cabinet 70 defines a processing chamber 70s which is a space for processing an object to be processed. When shot-processing the object to be processed, the object to be processed is placed in the processing chamber 70s, and the shot medium 2 is projected from the nozzle 15 toward the object to be processed in the processing chamber 70s so that the shot medium 2 collides with the object to be processed.

[0020] The control device 16 is a computer including a processor, a storage device, an input device, a display device, a communication device, etc., and controls the operation of the entire shot processing device 10. For example, the control device 16 loads a program stored in the storage device and executes the loaded program by the processor to realize various functions described later. With the control device 16, an operator can perform an input operation of a command or the like to manage the shot processing device 10 using the input device, and the operating status of the shot processing device 10 can be visualized and displayed by the display device.

[0021] The control device 16 determines the projection conditions of the shot medium 2 of the shot processing device 10, and controls the shot processing device 10 to project the shot medium 2 under the determined projection conditions. Here, the projection conditions are the conditions set for the shot processing device 10 to project the shot medium 2, and examples thereof include the injection pressure of the shot medium 2 and the injection amount of the shot medium 2.

[0022] Although not shown in FIG. 1, the shot processing apparatus 10 may further include a dust collecting device, a classification device, and a circulation device for recycling the used shot medium 2. The dust collecting device is connected to the processing chamber 70s via the classification device, and transfers the shot medium 2 that has fallen to the lower part of the processing chamber 70s and the chips of the object to be processed to the classification device by sucking them. The classification device is, for example, a cyclone type classification device, which receives the shot medium 2 and the chips of the object to be processed, and classifies them into particles that can be reused as the shot medium 2 and particles that cannot be used as the shot medium 2. The circulation device returns the reusable shot medium 2 to the shot medium tank 11 via a packet elevator, a screw conveyor, a separator, and the like.

[0023] As described above, the shot medium 2 projected from the nozzle 15 of the shot processing apparatus 10 collides with the object to be processed. Due to the collision of the shot medium 2, a force that spreads the surface of the object to be processed acts, and as a result, a reaction force that counteracts this force is generated in the object to be processed. As a result, compressive residual stress is applied to the object to be processed.

[0024] In the shot processing system 1, in order to confirm whether the intensity of the shot processing matches the required intensity, before performing the shot processing on the object to be processed, the sensor device 20 is subjected to the shot processing to measure the intensity of the shot processing. Then, it is periodically confirmed whether the measured intensity matches the required intensity. The measurement of the intensity is performed, for example, once or multiple times before performing the shot processing on the object to be processed.

[0025] When the shot medium 2 collides with an object by shot processing, a phenomenon called acoustic emission occurs in which elastic energy inside the object is released as elastic waves along with the deformation or destruction of the object. Elastic waves are waves such as vibrations or sound waves generated in the object by the collision of the shot medium 2. The sensor device 20 measures the elastic waves generated when the shot medium 2 collides, and outputs a signal waveform (hereinafter referred to as "AE signal waveform") indicating the measured elastic waves.

[0026] Figure 2(a) is a perspective view of an exemplary sensor device 20, and Figure 2(b) is a perspective view showing the main components of the sensor device 20 disassembled. As shown in Figures 2(a) and 2(b), the sensor device 20 includes a collision member 21, a waveguide member 22, and an AE sensor 23. The collision member 21 is a plate made of a hard material having wear resistance, and has a surface 21a for receiving the shot medium 2 projected from the shot processing device 10. The collision member 21 is fixed to the cover 24 so that the surface 21a is exposed.

[0027] The waveguide member 22 has a substantially cylindrical shape and has a first surface 22a and a second surface 22b disposed on the opposite side of the first surface 22a. The first surface 22a is in contact with the surface on the opposite side of the surface 21a of the collision member 21. When the shot medium 2 collides with the surface 21a of the collision member 21, the elastic wave generated in the collision member 21 is propagated from the first surface 22a to the second surface 22b.

[0028] The AE sensor 23 is, for example, a piezoelectric element that measures elastic waves. The AE sensor 23 is in contact with the second surface 22b of the waveguide member 22, measures the elastic wave propagated to the second surface 22b of the waveguide member 22, and outputs an AE signal waveform indicating the measured elastic wave. The AE signal waveform is a voltage waveform indicating the amplitude of the elastic wave. The sensor device 20 outputs the AE signal waveform measured by the AE sensor 23 to the intensity measurement device 30.

[0029] Note that depending on the material or projection conditions of the shot medium 2, the sensor device 20 may not include the collision member 21. In this case, the first surface 22a of the waveguide member 22 is exposed from the cover 24, and the shot medium 2 collides with the first surface 22a of the waveguide member 22. Then, the AE sensor 23 measures the elastic wave propagated from the first surface 22a to the second surface 22b of the waveguide member 22.

[0030] The intensity measurement device 30 is communicably connected to the sensor device 20 via the cable 26. Note that the intensity measurement device 30 may be connected to the sensor device 20 by wireless communication. The intensity measurement device 30 measures (estimates) the intensity of the shot process based on the AE signal waveform output from the sensor device 20.

[0031] FIG. 3 is a diagram showing the functional configuration of the intensity measurement device 30. As shown in FIG. 3, the intensity measurement device 30 includes, as functional components, a waveform acquisition unit 31, a time-series data generation unit 32, an average value acquisition unit 33, an intensity acquisition unit 34, and a communication unit 35.

[0032] The waveform acquisition unit 31 acquires the AE signal waveform from the sensor device 20. FIG. 4 shows an example of the AE signal waveform output from the sensor device 20 when the shot medium 2 collides with the surface 21a of the sensor device 20. As shown in FIG. 4, the AE signal waveform is a waveform whose amplitude varies with time.

[0033] The time-series data generation unit 32 generates time-series data of the effective value of the AE signal waveform. The effective value means the root mean square of the square of the amplitude of the AE signal waveform over the duration T of the AE signal waveform. Specifically, when the amplitude of the AE signal waveform is represented as a function f(t) of time t, the effective value RMS can be obtained from the following formula (1).

[0034]

Equation

[0035] FIG. 5 is data showing the effective value of the AE signal waveform shown in FIG. 4. As shown in FIG. 5, it can be said that the effective value of the AE signal waveform is time-series data that changes with time.

[0036] The average value acquisition unit 33 obtains the average value of the effective values over a predetermined time length L based on the generated time-series data of the effective values. The predetermined time length L is a set value set by the designer and is, for example, 3 seconds. For example, when the effective value at time ti (i = 1, 2, ···, n) within the predetermined time length L is RMSi, the average value RMS of the effective values avr can be obtained by the following formula (2). In formula (2), N is the number of samples of the effective values acquired at the sampling period Δt and can be expressed as (tn - t1) / Δt.

[0037]

Equation

[0038] Figure 6 is a graph showing the relationship between the average value of the effective values and the intensity of the shot process. This graph is generated, for example, based on the experimental results of past shot processes. As shown in Figure 6, there is a correlation between the average value of the effective values and the intensity of the shot process. The intensity acquisition unit 34 acquires the intensity of the shot process based on the correlation data showing the correlation between the average value of the effective values and the intensity of the shot process.

[0039] For example, the intensity acquisition unit 34 draws an approximate straight line or an approximate curve showing the correlation between the average value of the effective values and the intensity of the shot process on the graph shown in Figure 6, and generates a model formula showing the correlation between the average value of the effective values and the intensity from the approximate straight line or the approximate curve. The model formula showing the correlation between the average value of the effective values and the intensity can be expressed as a one-variable polynomial shown in the following formula (3). However, in formula (3), a n is a constant, x is the average value [V] of the effective values of the AE signal waveform over the predetermined time length L, and y is the intensity of the shot process [mmN]. Note that formula (3) can also be expressed as the following formula (4).

[0040]

Equation

[0041]

Number

[0042] Constant a n is set according to the characteristics (material, diameter, hardness, etc.) of the shot medium 2. The model formula is generated for each type of the shot medium 2. The intensity acquisition unit 34 obtains the intensity using the model formula corresponding to the type of the shot medium 2. Typically, the model formula showing the correlation between the average value of the effective value and the intensity is represented by the linear formula shown in the following formula (5) or the quadratic formula shown in the following formula (6).

[0043]

Number

[0044]

Number

[0045] Note that the intensity acquisition unit 34 may obtain the intensity corresponding to the average value of the effective value by referring to a table associating the average value of the effective value and the intensity without using the above formula (4). In this case, the table associating the average value of the effective value and the intensity is prepared for each type of the shot medium 2.

[0046] The communication unit 35 outputs data indicating the intensity acquired by the intensity acquisition unit 34 to an external device 40 by wired communication or wireless communication (see FIG. 7). The external device 40 is a computer for managing the intensity measurement device 30. The external device 40 may be a stationary or portable computer or workstation, or may be a portable terminal such as a notebook computer, a tablet terminal, a smartphone, or a PDA. The external device 40 displays the intensity output from the intensity measurement device 30 on a display device and presents it to the operator of the shot processing system 1. That is, the communication unit 35 constitutes an output unit that outputs the intensity of shot processing.

[0047] As described above, the intensity measurement device 30 takes the AE signal waveform from the sensor device 20 as an input, and based on the AE signal waveform, outputs the intensity of shot processing. The intensity y output from the intensity measurement device 30 satisfies the above formula (4).

[0048] (First Configuration Example) FIG. 7 shows a first configuration example of the intensity measurement device 30 that implements each function of the intensity measurement device 30. As shown in FIG. 7, the intensity measurement device 30 according to the first configuration example includes, as physical components, a charge amplifier (amplifier) 41, a variable gain 42, a filter 43, an AD converter 44, an FPGA (Field Programmable Gate Array) 45, a processor 46, and a communication device 47. For example, the charge amplifier 41, the variable gain 42, the filter 43, the AD converter 44, the FPGA 45, the processor 46, and the communication device 47 are mounted on the same substrate 50 and operate by the power of the battery 51.

[0049] The charge amplifier 41 is an amplifier circuit that amplifies the AE signal waveform. The charge amplifier 41 receives the AE signal waveform from the sensor device 20 via the cable 26, amplifies the AE signal waveform, and outputs it as a voltage signal. That is, the charge amplifier 41 constitutes a waveform acquisition unit 31 that acquires the AE signal waveform from the sensor device 20. The variable gain 42 adjusts the amplification factor (gain) of the charge amplifier 41 according to the output of the charge amplifier 41.

[0050] The filter 43 removes high-frequency components from the AE signal waveform amplified by the charge amplifier 41. The AD converter 44 samples the AE signal waveform output from the filter 43 at a predetermined sampling frequency and converts the AE signal waveform into digital data.

[0051] The FPGA 45 is an integrated circuit with a programmable logic gate circuit configuration and executes a predetermined operation according to a program at high speed. The FPGA 45 calculates the effective value at each time from the digital data of the AE signal waveform based on, for example, Equation (1), and generates time-series data of the effective values. Note that the operation of the FPGA 45 is controlled by a switching signal received from the switch 53 via the trigger 54.

[0052] In addition, the FPGA 45 calculates the average value of the effective values based on the generated time-series data of the effective values. For example, the FPGA 45 extracts a plurality of effective values included in a predetermined time length L from the time-series data and calculates the average value of the plurality of effective values. That is, the FPGA 45 constitutes a time-series data generation unit 32 and an average value acquisition unit 33. The predetermined time length L is stored in, for example, the memory 52. The FPGA 45 stores the calculated average value of the effective values in the memory 52. Note that the memory 52 may be built into the FPGA 45.

[0053] The processor 46 is composed of a computing device such as a microcomputer or a PLC. The processor 46 reads out the average value of the effective values stored in the memory 52, and calculates the intensity of the shot process based on the average value of the effective values. For example, a model formula corresponding to the type of the shot medium 2 is read out from the memory 52, and the intensity corresponding to the average value of the effective values is calculated using the model formula. As the model formula used for calculating the intensity, the one shown in the above formula (4) is used. That is, the processor 46 constitutes the intensity acquisition unit 34.

[0054] Note that the generation process of the time-series data of the effective values, the calculation process of the average value of the effective values, and the calculation process of the intensity may be assigned to either the FPGA 45 or the processor 46. For example, the FPGA 45 may execute the generation process of the time-series data of the effective values, the calculation process of the average value of the effective values, and the calculation process of the intensity. In this case, the FPGA 45 constitutes the time-series data generation unit 32, the average value acquisition unit 33, and the intensity acquisition unit 34. Also, only the generation process of the time-series data of the effective values may be assigned to the FPGA 45, and the calculation process of the average value of the effective values and the calculation process of the intensity may be assigned to the processor 46. In this case, the FPGA 45 constitutes the time-series data generation unit 32, and the processor 46 constitutes the average value acquisition unit 33 and the intensity acquisition unit 34.

[0055] The communication device 47 is a device that communicates with the external device 40 by wired communication or wireless communication. Examples of the wired communication or wireless communication include LAN, Bluetooth (registered trademark), Wifi, etc. The communication device 47 transmits information indicating the calculated intensity of the shot process to the external device 40. The intensity received by the external device 40 is displayed on the display device of the external device 40.

[0056] As described above, in the intensity measurement device 30 according to the first configuration example, since the generation process of the time-series data of the effective value that requires a large computational load is assigned to the FPGA 45, the speed of intensity measurement can be increased. Further, since the charge amplifier 41, variable gain 42, filter 43, AD converter 44, FPGA 45, processor 46, and communication device 47 are mounted on the same substrate 50, the size of the intensity measurement device 30 can be reduced.

[0057] (Second Configuration Example) Next, a second configuration example of the intensity measurement device 30 will be described. FIG. 8 shows the second configuration example of the intensity measurement device 30. As shown in FIG. 8, the intensity measurement device 30 according to the second configuration example includes, as physical components, a charge amplifier 41, a variable gain 42, a filter 43, an AD converter 44, a processor 46, a communication device 47, and an RMS-DC converter 48. The charge amplifier 41, variable gain 42, filter 43, AD converter 44, processor 46, communication device 47, and RMS-DC converter 48 are mounted on the same substrate 50 and operate by the power of the battery 51.

[0058] That is, the intensity measurement device 30 according to the second configuration example differs from the intensity measurement device 30 according to the first configuration example in that it includes an RMS-DC converter 48 instead of the FPGA 45. Hereinafter, the description will focus on the differences from the intensity measurement device 30 according to the first configuration example, and overlapping descriptions will be omitted.

[0059] The RMS-DC converter 48 is a circuit that outputs an output value indicating the effective value of the AE signal waveform. For example, the input of the RMS-DC converter 48 is the AE signal waveform shown in FIG. 4, and the output of the RMS-DC converter 48 is the effective value that changes over time shown in FIG. 5. In the second configuration example, the RMS-DC converter 48 constitutes the time-series data generation unit 32.

[0060] In one embodiment, as shown in FIG. 8, the RMS-DC converter 48 is disposed between the filter 43 and the AD converter 44, receives the AE signal waveform output from the filter 43, and outputs an output value indicating the effective value of the AE signal waveform. The output value output from the RMS-DC converter 48 is a voltage value corresponding to the effective value of the AE signal waveform that changes over time, and can be said to be time-series data of the effective value. The AD converter 44 samples the output value output from the RMS-DC converter 48 at a predetermined frequency and converts it into digital data.

[0061] The processor 46 calculates the average value of the effective values based on the digital data of the effective values output from the AD converter 44. For example, the processor 46 extracts a plurality of effective values included in a predetermined time length L from the digital data of the effective values and calculates the average value of the plurality of effective values.

[0062] Further, the processor 46 calculates the intensity of the shot process based on the calculated average value of the effective values. For example, the processor 46 reads out a model formula corresponding to the type of the shot medium 2 from the memory 52 and calculates the intensity corresponding to the average value of the effective values using the model formula. The calculated intensity is transmitted to the external device 40 by the communication device 47.

[0063] As described above, in the intensity measurement device 30 according to the second configuration example, since the time-series data of the effective values is generated using the RMS-DC converter 48, the computational load on the processor 46 can be reduced. Therefore, the speed of intensity measurement can be increased.

[0064] As described above, in the intensity measurement device 30 described above, the intensity of shot peening is obtained from the average value of the effective value. Since there is a certain correlation between the average value of the effective value and the intensity, the intensity of shot peening can be obtained from the average value of the effective value without measuring the arc height of the test piece using a micrometer. In particular, as shown in Equation (4), since the average value of the effective value and the intensity can be expressed by a polynomial of one variable, the intensity of shot peening can be calculated from the average value of the effective value without complicated calculations. Therefore, the calculation load of the intensity measurement device 30 can be reduced. Further, since the effective value of the AE signal waveform varies with time, if the intensity is obtained from the instantaneous value of the effective value, there is a risk of outputting an intensity deviated from the true intensity. Therefore, by estimating the intensity using the average value of the effective value, the estimated value of the intensity can be made closer to the true intensity.

[0065] The operator of the shot peening system 1 compares the intensity required to impart a desired compressive residual stress (hereinafter referred to as "required intensity") with the intensity measured by the intensity measurement device 30 (hereinafter referred to as "measured intensity"), and determines whether the difference between the required intensity and the measured intensity falls within a specified management range. When the difference between the required intensity and the measured intensity falls within the specified management range, the shot medium 2 is projected onto the object to be processed under the set projection conditions.

[0066] On the other hand, when the difference between the required intensity and the measured intensity does not fall within the specified management range, the projection conditions of the shot processing apparatus 10 are corrected so that the difference between the required intensity and the measured intensity becomes smaller. For example, when the measured intensity is smaller than the required intensity, the projection conditions are corrected so that the injection pressure or the injection amount of the shot medium 2 becomes larger, and the shot medium 2 is projected onto the object to be processed under the corrected projection conditions. Conversely, when the measured intensity is larger than the required intensity, the projection conditions are corrected so that the injection pressure or the injection amount of the shot medium 2 becomes smaller, and the shot medium 2 is projected onto the object to be processed under the corrected projection conditions. As a result, a desired compressive residual stress can be imparted to the object to be processed.

[0067] Next, an intensity measurement method for measuring the intensity of shot processing using the intensity measurement apparatus 30 described above will be described. FIG. 9 is a flowchart showing an intensity measurement method according to an embodiment.

[0068] In this method, first, the shot medium 2 is projected from the shot processing apparatus 10 onto the surface 21a of the sensor apparatus 20 (step ST1). When the shot medium 2 collides with the surface 21a, a part of the strain energy is released as an elastic wave along with the deformation or breakage of the collision member 21. The sensor apparatus 20 measures the elastic wave generated by the collision of the shot medium 2 and outputs it as an AE signal waveform.

[0069] Next, the waveform acquisition unit 31 of the intensity measurement apparatus 30 acquires the AE signal waveform from the sensor apparatus 20 (step ST2). Next, the time series data generation unit 32 generates time series data of the effective value of the AE signal waveform (step ST3). The time series data of the effective value may be generated by calculating the effective value at each time based on the above formula (1) by the FPGA 45 or the processor 46, or may be generated using the RMS-DC converter 48.

[0070] Next, the average value acquisition unit 33 obtains the average value of the effective values over a predetermined time length L (step ST4). The average value of the effective values is obtained by the FPGA 45 or the processor 46 extracting a plurality of effective values included in the predetermined time length L from the time series data of the effective values and calculating the average value of the plurality of effective values.

[0071] Next, the intensity acquisition unit 34 obtains the intensity of the shot process based on the average value of the effective values (step ST5). For example, the intensity is calculated by the FPGA 45 or the processor 46 applying the average value of the effective values to the above formula (4).

[0072] Next, the communication unit 35 outputs the obtained intensity to the external device 40 (step ST6). The external device 40 displays the intensity measured by the sensor device 20 on a display device. The operator of the shot process system 1 sets the projection conditions of the shot process device 10 based on the displayed intensity.

[0073] As described above, the intensity measurement device, the intensity measurement system, and the intensity measurement method according to various embodiments have been described. However, the present invention is not limited to the above-described embodiments, and various modifications can be configured without changing the gist of the invention. That is, it should be noted that the above-described embodiments are for illustrative purposes and do not limit the scope of the present invention.

[0074] For example, in the above-described embodiment, the intensity measurement device 30 measures the intensity from the AE signal waveform output from the sensor device 20. However, the intensity measurement device 30 can measure the intensity from the AE signal waveform output from any sensor. For example, as shown in FIG. 1, when an AE sensor 23 for measuring elastic waves is provided at the nozzle 15 of the shot processing device 10, the intensity measurement device 30 may measure the intensity of the shot processing based on the AE signal waveform output from the AE sensor 23. In this case, the intensity of the shot processing can be measured based on the AE signal waveform indicating the elastic waves generated at the nozzle 15 when the shot medium 2 is projected.

[0075] Also, in the first configuration example shown in FIG. 7, at least a part of the generation process of the effective value time-series data, the calculation process of the average value of the effective value, and the calculation process of the intensity are assigned to the FPGA 45. However, in one embodiment, at least a part of these processes may be assigned to an ASIC (Application Specific Integrated Circuit).

[0076] Also, in the second configuration example shown in FIG. 8, an RMS-DC converter 48 is used instead of the FPGA 45. However, the intensity measurement device 30 may include both the FPGA 45 and the RMS-DC converter 48, and at least a part of the calculation process of the average value of the effective value and the calculation process of the intensity may be assigned to the FPGA 45.

[0077] Note that the above-described various embodiments can be combined within a non-contradictory range.

[0078] [Forms included in the present disclosure] The present disclosure includes the forms described in the following clauses.

[0079] (Clause 1) The intensity measurement device according to one aspect is connected to a sensor device that outputs a signal waveform related to elastic waves generated by shot peening, and measures the intensity of the shot peening based on the signal waveform. This intensity measurement device includes a waveform acquisition unit that acquires the signal waveform from the sensor device, a time-series data generation unit that generates time-series data of the effective value of the signal waveform, an average value acquisition unit that obtains the average value of the effective value over a predetermined time length based on the time-series data, and an intensity acquisition unit that obtains the intensity of the shot peening based on the average value of the effective value. There is a certain correlation between the average value of the effective value and the intensity of the shot peening. In the intensity measurement device according to this aspect, since the intensity is obtained from the average value of the effective value, the intensity of the shot peening can be acquired without measuring the arc height of the test piece using a micro gauge. Therefore, the intensity can be easily measured in a short time.

[0080] (Clause 2) In the intensity measurement device according to Clause 1, the intensity acquisition unit may calculate the intensity y based on the following formula (1).

Equation

[0081] (Clause 3) The intensity measurement device according to Clause 1 or 2 may further include a communication unit that sends the intensity to an external device. By transmitting the intensity to an external device, the amount of data transferred to the external device can be reduced compared to the case of transmitting the signal waveform to the external device.

[0082] (Clause 4) The intensity measurement device according to any one of Clauses 1 to 3 includes an amplifier constituting a waveform acquisition unit, an FPGA constituting a time-series data generation unit, and an AD converter. The amplifier amplifies the signal waveform output from the sensor device, the AD converter samples the amplified signal waveform and converts it into digital data, and the FPGA may generate time-series data of the effective value from the digital data. To generate time-series data of the effective value, a large amount of computational effort is required and it takes a long time. By assigning the process of generating time-series data of the effective value to the FPGA, the measurement time of the intensity can be shortened.

[0083] (Clause 5) In the intensity measurement device according to any one of Clause 4, the FPGA may calculate the average value of the effective value over a predetermined time length from the time-series data of the effective value. By assigning the process of calculating the average value of the effective value to the FPGA, the measurement time of the intensity can be further shortened.

[0084] (Clause 6) In the intensity measurement device according to Clause 4 or 5, the amplifier, the FPGA, and the AD converter may be arranged on the same substrate. In this case, the intensity measurement device can be miniaturized.

[0085] (Clause 7) The intensity measurement device according to any one of Clauses 1 to 3 includes an amplifier constituting a waveform acquisition unit, an RMS-DC converter constituting a time-series data generation unit, and an AD converter. The amplifier amplifies the signal waveform output from the sensor device, the RMS-DC converter receives the signal waveform and outputs an output value indicating the effective value of the signal waveform that changes over time, and the AD converter may sample the output value and convert the effective value of the signal waveform into digital data. In this case, since an output value indicating the effective value of the signal waveform is output from the RMS-DC converter, the computational load of calculating the effective value of the signal waveform can be reduced. Therefore, the intensity can be measured efficiently.

[0086] (Clause 8) The intensity measurement device described in Clause 7 further includes a processor that constitutes an average value acquisition unit and an intensity acquisition unit. The processor may calculate the average value of the effective value over a predetermined time period based on the digital data, and calculate the intensity of the shot process based on the average value of the effective value. In this case, since the intensity is calculated based on the output value output from the RMS-DC converter, the computational load on the processor can be reduced.

[0087] (Clause 9) An intensity measurement device according to another aspect is connected to a sensor device that outputs a signal waveform related to the elastic wave generated by the shot process, and measures the intensity of the shot process based on the signal waveform. This intensity measurement device includes a waveform acquisition unit that acquires the signal waveform from the sensor device, and an output unit that outputs the intensity of the shot process based on the signal waveform. The intensity y output from the output unit satisfies the following formula (2).

Equation

[0088] (Clause 10) An intensity measurement system according to one aspect includes a sensor device that outputs a signal waveform related to an elastic wave generated by shot processing, a waveform acquisition unit that acquires the signal waveform from the sensor device, a time-series data generation unit that generates time-series data of the effective value of the signal waveform, an average value acquisition unit that obtains an average value of the effective value over a predetermined time length based on the time-series data, and an intensity acquisition unit that obtains the intensity of the shot processing based on the average value of the effective value. In this intensity measurement system, since the intensity is obtained from the average value of the effective value, the intensity can be easily measured in a short time.

[0089] (Clause 11) In the intensity measurement device according to Clause 10, the sensor device may include a collision member having a surface that receives the shot medium, a first surface in contact with the collision member and a second surface on the opposite side of the first surface, a waveguide member that propagates an elastic wave generated by the collision of the shot medium from the first surface to the second surface, and an AE sensor that detects the elastic wave propagated to the second surface and outputs a signal waveform. By measuring the elastic wave propagated through the waveguide member with the AE sensor, the AE sensor can be protected, and thus the failure of the AE sensor can be prevented.

[0090] (Clause 12) In the intensity measurement device according to Clause 10, the sensor device may include a first surface that receives the shot medium and a second surface on the opposite side of the first surface, a waveguide member that propagates an elastic wave generated by the collision of the shot medium from the first surface to the second surface, and an AE sensor that detects the elastic wave propagated to the second surface and outputs a signal waveform.

[0091] (Article 13) The intensity measurement method according to one aspect includes: a step of acquiring a signal waveform related to an elastic wave generated by shot processing from a sensor device; a step of generating time-series data of the effective value of the signal waveform; a step of obtaining an average value of the effective value over a predetermined time length based on the time-series data; and a step of obtaining the intensity of the shot processing based on the average value of the effective value. In this intensity measurement method, since the intensity is obtained from the average value of the effective value, the intensity can be easily measured in a short time.

Description of Reference Numerals

[0092] 2... Shot medium, 20... Sensor device, 21... Collision member, 21a... Surface, 22... Waveguide member, 22a... First surface, 22b... Second surface, 23... AE sensor, 30... Intensity measurement device, 31... Waveform acquisition unit, 32... Time-series data generation unit, 33... Average value acquisition unit, 34... Intensity acquisition unit, 35... Communication unit, 40... External device, 41... Charge amplifier, 45... FPGA, 46... Processor, 48... RMS-DC converter.

Claims

1. An intensity measurement device that is connected to a sensor device that outputs a signal waveform related to an elastic wave generated by shot processing, and measures the intensity of the shot processing based on the signal waveform, comprising: a waveform acquisition unit that acquires the signal waveform from the sensor device; a time-series data generation unit that generates time-series data of the effective value of the signal waveform; an average value acquisition unit that obtains an average value of the effective value over a predetermined time length based on the time-series data; an intensity acquisition unit that obtains the intensity of the shot processing based on the average value of the effective value; An intensity measurement device comprising:

2. The intensity measurement device according to claim 1, wherein the intensity acquisition unit calculates the intensity y based on the following formula (1). 【Number 1】 However, a ｋ is a constant, and x is the average value of the effective value.

3. The intensity measurement device according to claim 1, further comprising a communication unit that sends the intensity to an external device.

4. an amplifier that constitutes the waveform acquisition unit; an FPGA that constitutes the time-series data generation unit; an AD converter; comprising: The amplifier amplifies the signal waveform output from the sensor device; The AD converter samples the amplified signal waveform and converts it into digital data; The FPGA calculates the effective value at each time from the digital data and generates time-series data of the effective value. The intensity measurement device according to claim 1.

5. The intensity measurement device according to claim 4, wherein the FPGA calculates an average value of the effective value over the predetermined time length based on the effective value at each time.

6. The intensity measurement device according to claim 4 or 5, wherein the amplifier, the FPGA, and the AD converter are arranged on the same substrate.

7. an amplifier that constitutes the waveform acquisition unit; an RMS-DC converter that constitutes the time-series data generation unit; an AD converter; comprising: The amplifier amplifies the signal waveform output from the sensor device; The RMS-DC converter inputs the signal waveform and outputs an output value indicating the effective value of the signal waveform that changes over time; The AD converter samples the output value and converts the effective value of the signal waveform into digital data. The intensity measurement device according to claim 1.

8. further comprising a processor that constitutes the average value acquisition unit and the intensity acquisition unit, The intensity measurement device according to claim 7, wherein the processor calculates an average value of the effective value in the predetermined time length based on the digital data, and calculates the intensity of the shot process based on the average value of the effective value.

9. An intensity measurement device connected to a sensor device that outputs a signal waveform related to an elastic wave generated by shot peening, and measures the intensity of the shot peening based on the signal waveform, a waveform acquisition unit that acquires the signal waveform from the sensor device; an output unit that outputs the intensity of the shot process based on the signal waveform; comprising: The intensity y output from the output unit satisfies the following formula (2). The intensity measurement device. 【Number 2】 However, a ｋ is a constant, and x is the average value of the effective value of the signal waveform over a predetermined time period.

10. A sensor device that outputs a signal waveform related to an elastic wave generated by shot peening, a waveform acquisition unit that acquires the signal waveform from the sensor device; a time-series data generation unit that generates time-series data of the effective value of the signal waveform; an average value acquisition unit that obtains an average value of the effective value in a predetermined time length based on the time-series data; an intensity acquisition unit that obtains the intensity of the shot process based on the average value of the effective value; An intensity measurement system comprising:

11. The sensor device a collision member having a surface for receiving a shot medium; a waveguide member having a first surface in contact with the collision member and a second surface opposite to the first surface, and propagating an elastic wave generated by the collision of the shot medium from the first surface to the second surface; an AE sensor that detects the elastic wave propagated to the second surface and outputs the signal waveform; The intensity measurement system according to claim 10, comprising:

12. The sensor device has a first surface for receiving a shot medium and a second surface opposite to the first surface, and a waveguide member that propagates an elastic wave generated by the collision of the shot medium from the first surface to the second surface; an AE sensor that detects the elastic wave propagated to the second surface and outputs the signal waveform; The intensity measurement system according to claim 10, comprising:

13. a step of acquiring a signal waveform related to an elastic wave generated by shot peening from a sensor device; a step of generating time-series data of the effective value of the signal waveform; a step of obtaining an average value of the effective value in a predetermined time length based on the time-series data; A step of obtaining the intensity of the shot treatment based on the average value of the effective value; An intensity measurement method including this.

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