Strength measurement device, strength measurement system, and strength measurement method

Abstract

The invention relates to a strength measuring device, a strength measuring system and a strength measuring method. An intensity measurement device according to one embodiment is connected to a sensor device that outputs a signal waveform relating to an elastic wave generated by a shot peening process, and measures the intensity of the shot peening process on the basis of the signal waveform. The intensity measurement device includes: a waveform acquisition unit that acquires a signal waveform from a 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 values within a predetermined time length on the basis of the time-series data; and a strength acquisition unit for obtaining the strength of the shot peening treatment on the basis of the average value of the effective values.

Description

Technical Field

[0001] The present disclosure relates to a strength measurement device, a strength measurement system, and a strength measurement method. Background Art

[0002] In shot peening such as shot peening or peen forming, a shot medium is projected onto an object to be processed. In the case of performing shot peening, in order to bring the object to be processed into an appropriate processing state corresponding to its use, it is required to cause the shot medium to collide with the object to be processed with an appropriate strength.

[0003] Generally, strength is used as an index for quantitatively representing the intensity of shot peening. The strength corresponds to the arc height at the time when the increase ratio of the arc height read from the shot time-arc height saturation curve created by measuring the arc height (the warpage amount of the test piece) after shot peening a test piece at any time is within 10%. In the specification of U.S. Patent No. 2350440, a metal plate used as a test piece for measuring strength is described. The metal plate for strength measurement is also called an almen strip.

[0004] In order to obtain the arc height saturation curve, it is necessary to project a shot medium onto a plurality of almen strips to measure the arc height. Since the almen strip cannot be reused and thus waste is generated, it is not preferable from the viewpoints of cost and environmental load. In addition, in order to obtain the arc height saturation curve by measuring the arc height value with a micrometer, a great deal of effort is required, and thus there is a problem that the measurement of strength takes time. Summary of the Invention

[0005] Therefore, an object of the present disclosure is to provide a strength measurement device, a strength measurement system, and a strength measurement method capable of efficiently measuring strength.

[0006] A strength 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 strength of shot peening based on the signal waveform. The strength measurement device includes a waveform acquisition unit, a time series data generation unit, an average value acquisition unit, and a strength 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 calculates the average value of the effective values within a specified time length based on the time series data. The strength acquisition unit calculates the strength of the shot peening based on the average value of the effective values.

[0007] According to various aspects of the present disclosure, strength can be efficiently measured. Brief Description of the Drawings

[0008] Figure 1 is a diagram schematically showing a shot peening system according to one embodiment.

[0009] Figure 2 FIG. (a) is a perspective view of an exemplary sensor device. Figure 2 FIG. (b) is a perspective view showing the main components of the sensor device disassembled.

[0010] Figure 3 is a diagram showing the functional configuration of the intensity measurement device.

[0011] Figure 4 is a diagram showing an example of the signal waveform output from the sensor device.

[0012] Figure 5 is a diagram showing the temporal change of the effective value of the signal waveform.

[0013] Figure 6 is a graph showing the relationship between the average value of the effective value and the intensity of shot peening.

[0014] Figure 7 is a diagram showing a first configuration example of the intensity measurement device.

[0015] Figure 8 is a diagram showing a second configuration example of the intensity measurement device.

[0016] Figure 9 is a flowchart showing the intensity measurement method according to one embodiment.

[0017] Explanation of Reference Numerals

[0018] 2... Shot peening medium; 20... Sensor device; 21... Impact 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 (amplifier); 45... FPGA; 46... Processor; 48... RMS-DC converter. Detailed Embodiment

[0019] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In addition, in the following description, the same or corresponding elements are denoted by the same reference numerals, and repeated explanations are not repeated. The dimensional ratios of the drawings do not necessarily match the content of the description.

[0020] [Example of Embodiment of the Present Disclosure]

[0021] Figure 1 is a diagram schematically showing a shot peening system according to one embodiment. Figure 1The shot peening system 1 shown projects shot peening media under set projection conditions. In addition, in this specification, the process of projecting shot peening media from a shot peening device is referred to as shot peening. Shot peening includes shot blasting for purposes such as descaling, deburring, and surface roughness adjustment, and shot peening hardening for the purpose of imparting compressive residual stress to the object to be processed.

[0022] As Figure 1 shown, the shot peening system 1 includes a shot peening device 10, a sensor device 20, and a strength measurement device 30. The shot peening device 10 processes the surface of the object to be processed by causing the shot peening media to collide with the object to be processed by projecting the shot peening media onto the object to be processed. For example, the shot peening device 10 is a shot peening hardening device that imparts compressive residual stress to the surface of the object to be processed. Examples of objects to be processed by shot peening using the shot peening device 10 include automotive components such as cylinder heads and crankshafts, gears, and dies, but the objects to be processed are not limited to these. By shot peening, compressive residual stress is imparted to the surface of the object to be processed, thereby improving the fatigue characteristics of the object to be processed.

[0023] The compressive residual stress that should be imparted to the object to be processed is determined according to the use of the object to be processed. In order to impart 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 appropriate strength. Generally, strength is used as an index for quantitatively representing the intensity of shot peening. Strength corresponds to the arc height at a time when the increase ratio of the arc height read from the shot peening time-arc height saturation curve created by measuring the arc height value after shot peening a test piece for an arbitrary period of time is within 10%. The calculation method of strength is specified in SAE standard J443 (2010).

[0024] The shot peening device 10 can be an air type that sprays the shot peening media as a solid-gas two-phase flow together with compressed air, or a centrifugal type that projects the shot peening media using the centrifugal force generated by the rotation of an impeller called a turbine. Figure 1 The shot peening device 10 shown is a direct pressure type shot peening hardening device. In addition, the shot peening device 10 can also be a suction type or a gravity type shot peening hardening device. Further, the shot peening device 10 can also be a wet type shot peening hardening device. The material of the shot peening media 2 projected onto the object to be processed can be, for example, ferrous metals such as steel and iron, non-ferrous metals such as stainless steel, or non-metals such as glass and zirconia. The shape of the shot peening media 2 can be spherical, or the shape after rounding the corners of a granular material (so-called cut wire) obtained by cutting a drawn wire into a specified length. As the shot peening media 2, for example, steel balls are used. In addition, the material, shape, and particle size of the shot peening media 2 are appropriately selected according to the compressive residual stress that should be imparted to the object to be processed.

[0025] As Figure 1 shown, the shot peening device 10 includes a shot peening medium tank 11, a shot peening medium supply device 12, a pressure tank 13, a compressor 14, a nozzle 15, and a control device 16. The shot peening medium tank 11 stores the shot peening medium 2. The shot peening medium tank 11 is connected to the pressure tank 13 via the shot peening medium supply device 12. A switchable poppet valve 64 is provided between the shot peening medium supply device 12 and the pressure tank 13. By opening the poppet valve 64, the shot peening medium 2 stored inside the shot peening medium tank 11 is supplied to the pressure tank 13 via the shot peening medium supply device 12.

[0026] The compressor 14 generates compressed air and supplies the compressed air to the pressure tank 13 and the nozzle 15. One end of a pipe 61 is connected to the compressor 14. The other end of the pipe 61 is connected to a pipe 63 described later. A pipe 62 branches 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 pressure 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 in the pipe 62. When the air flow rate adjustment valve 68 is opened, the compressed air from the compressor 14 is supplied to the pressure tank 13 via the pipe 61 and the pipe 62. By supplying compressed air from the compressor 14 to the pressure tank 13, the inside of the pressure tank 13 is pressurized.

[0027] The pressure tank 13 has a shot peening outlet 13B through which the shot peening medium 2 flows out. A switchable shut-off gate 60 is provided at the shot peening outlet 13B. A pipe 63 is connected to the shot peening outlet 13B via the shut-off gate 60. A shot peening amount adjustment valve 65 is provided in the pipe 63, and the shot peening amount adjustment valve 65 adjusts the amount of the shot peening medium 2 ejected from the nozzle 15. 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 that mixes the shot peening medium 2 supplied from the pressure tank 13 and the compressed air supplied from the compressor 14. The mixing portion 25A is located downstream of the branch portion 25B where the pipe 62 branches from the pipe 61 in the flow direction of the compressed air.

[0028] An air flow rate adjustment valve 66 is provided at a position between the mixing portion 25A and the branch portion 25B of 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 has been adjusted by the air flow rate adjustment valve 66 is mixed with the shot peening medium 2 supplied from the pressure tank 13 in the mixing portion 25A and is transported to the nozzle 15.

[0029] The nozzle 15 is provided at the front end of the pipe 63, and injects the shot medium 2 supplied from the pressure tank 13 and the compressed air together as a solid-gas two-phase flow. The nozzle 15 is arranged inside the cabinet 70. The cabinet 70 demarcates a space for processing the object to be processed, that is, the processing chamber 70s. When performing shot peening on the object to be processed, the object to be processed is arranged 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.

[0030] The control device 16 is a computer equipped with a processor, a storage device, an input device, a display device, a communication device, etc., and controls the operation of the entire shot peening device 10. The control device 16 realizes various functions described below, for example, by loading a program stored in the storage device and using the processor to execute the loaded program. In the control device 16, the operator uses the input device to manage the shot peening device 10, so that input operations of instructions and the like can be performed. In addition, the operating status of the shot peening device 10 can be visually displayed through the display device.

[0031] The control device 16 determines the projection conditions of the shot medium 2 of the shot peening device 10, and controls the shot peening device 10 so as to project the shot medium 2 under the determined projection conditions. Here, the projection conditions refer to the conditions set in the shot peening device 10 for projecting 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.

[0032] Although not shown in Figure 1 the shot peening device 10 may also be provided with a dust collection device, a classification device, and a circulation device in order to reuse the used shot medium 2. The dust collection 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 suction. The classification device is, for example, a cyclone 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 shot medium 2 that can be reused to the shot medium tank 11 via a bucket elevator, a screw conveyor, a separator, etc.

[0033] As described above, the shot medium 2 projected from the nozzle 15 of the shot peening device 10 collides with the object to be processed. Due to the collision of the shot medium 2, a force of hammering and stretching acts on the surface of the object to be processed, and as a result, a reaction force that overcomes this force is generated in the object to be processed. As a result, compressive residual stress is imparted to the object to be processed.

[0034] In the shot peening system 1, in order to confirm whether the intensity of the shot peening conforms to the required intensity, the sensor device 20 is shot peened before shot peening the object to be processed to measure the intensity of the shot peening. Moreover, it is regularly confirmed whether the measured intensity conforms to the required intensity. The measurement of the intensity is performed, for example, once or more times before shot peening the object to be processed.

[0035] When the shot peening medium 2 collides with an object due to shot peening, a phenomenon called acoustic emission occurs in which elastic energy inside the object is released as elastic waves along with the deformation or breakage of the object. Elastic waves are waves such as vibrations or sound waves generated in the object due to the collision of the shot peening medium 2. The sensor device 20 measures the elastic waves generated when the shot peening medium 2 collides and outputs a signal waveform representing the measured elastic waves (hereinafter referred to as the "AE signal waveform").

[0036] Figure 2 (a) is a perspective view of an exemplary sensor device 20, Figure 2 (b) is a perspective view showing the main components of the sensor device 20 disassembled. As Figure 2 shown in (a) and (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 peening medium 2 projected from the shot peening device 10. The collision member 21 is fixed to the cover 24 such that the surface 21a is exposed.

[0037] 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 of the collision member 21 on the side opposite to the surface 21a. When the shot peening medium 2 collides with the surface 21a of the collision member 21, the elastic waves generated in the collision member 21 propagate from the first surface 22a to the second surface 22b.

[0038] 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 waves propagated to the second surface 22b of the waveguide member 22, and outputs an AE signal waveform representing the measured elastic waves. The AE signal waveform is a voltage waveform representing the amplitude of the elastic waves. The sensor device 20 outputs the AE signal waveform measured by the AE sensor 23 to the intensity measurement device 30.

[0039] In addition, depending on the material of the shot peening medium 2 or the projection conditions, 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 peening medium 2 collides with the first surface 22a of the waveguide member 22. Further, the AE sensor 23 measures the elastic wave that propagates from the first surface 22a to the second surface 22b of the waveguide member 22.

[0040] The intensity measurement device 30 is communicably connected to the sensor device 20 via the cable 26. In addition, the intensity measurement device 30 may also be connected to the sensor device 20 by wireless communication. The intensity measurement device 30 measures (infers) the intensity of the shot peening process based on the AE signal waveform output from the sensor device 20.

[0041] Figure 3 It is a diagram showing the functional configuration of the intensity measurement device 30. As Figure 3 shown, the intensity measurement device 30 includes 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 as functional configuration elements.

[0042] The waveform acquisition unit 31 acquires the AE signal waveform from the sensor device 20. Figure 4 An example of the AE signal waveform output from the sensor device 20 when the shot peening medium 2 collides with the surface 21a of the sensor device 20 is shown. As Figure 4 shown, the AE signal waveform is a waveform whose amplitude varies with time.

[0043] The time series data generation unit 32 generates time series data of the effective value of the AE signal waveform. The effective value refers to the root mean square of the amplitude of the AE signal waveform within the duration T of the AE signal waveform. Specifically, when the amplitude of the AE signal waveform is expressed as a function f(t) of time t, the effective value RMS can be obtained according to the following formula (1).

[0044]

Equation 1

[0045]

[0046] Figure 5 is to represent Figure 4 the data of the effective value of the AE signal waveform shown in Figure 5 shown, the effective value of the AE signal waveform can be said to be time series data that changes with time.

[0047] The average value obtaining unit 33 calculates the average value of the effective values within a specified time length L based on the generated time series data of the effective values. The specified time length L is a set value set by the designer and is, for example, 3 seconds. For example, when the effective values at times ti (i = 1, 2,..., n) within the specified time length L are set as RMSi, the average value RMS of the effective values avr can be calculated by the following formula (2). In addition, in formula (2), N is the number of samples of the effective values obtained in the sampling period Δt and can be expressed as (tn - t1) / Δt.

[0048]

Equation 2

[0049]

[0050] Figure 6 is a graph showing the relationship between the average value of the effective values and the intensity of the shot peening treatment. This graph is generated, for example, based on the experimental results of past shot peening treatments. As Figure 6 shown, there is a correlation between the average value of the effective values and the intensity of the shot peening treatment. The intensity obtaining unit 34 obtains the intensity of the shot peening treatment based on the correlation data indicating the correlation between the average value of the effective values and the intensity of the shot peening treatment.

[0051] For example, the intensity obtaining 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 peening treatment in the Figure 6 shown graph, and generates a model formula showing the correlation between the average value of the effective values and the intensity based on this approximate straight line or approximate curve. The model formula showing the correlation between the average value of the effective values and the intensity can be expressed as a polynomial of one variable shown in the following formula (3). Among them, in formula (3), a n is a constant, x is the average value [V] of the effective values of the AE signal waveform within the specified time length L, and y is the intensity [mmN] of the shot peening treatment. In addition, formula (3) can also be expressed as the following formula (4).

[0052]

Equation 3

[0053] y = a n x n + a n-1 x n-1 + … + a 1 x + a 0 (3)

[0054]

Equation 4

[0055]

[0056] The constant a nIt is set according to the characteristics (material, diameter, hardness, etc.) of the shot peening medium 2. The model formula is generated for each type of the shot peening medium 2. The strength acquisition unit 34 obtains the strength by using the model formula corresponding to the type of the shot peening medium 2. Typically, the model formula representing the correlation between the average value of the effective value and the strength is expressed as a linear formula shown in the following formula (5) or a quadratic formula shown in the following formula (6).

[0057]

Equation 5

[0058] y = a 1 x + a 0 (5)

[0059]

Equation 6

[0060] y = a 2 x 2 + a 1 x + a 0 (6)

[0061] In addition, the strength acquisition unit 34 may also obtain the strength corresponding to the average value of the effective value by referring to a table that correlates the average value of the effective value with the strength, without using the above formula (4). In this case, a table that correlates the average value of the effective value with the strength is prepared for each type of the shot peening medium 2.

[0062] The communication unit 35 outputs data representing the strength obtained by the strength acquisition unit 34 to the external device 40 (refer to Figure 7 ) through wired communication or wireless communication. The external device 40 is a computer for managing the strength measurement device 30. The external device 40 may be a fixed or portable computer or workstation, or may also be a mobile terminal such as a laptop computer, a tablet terminal, a smart phone, a PDA, etc. The external device 40 displays the strength output from the strength measurement device 30 on a display device to prompt the operator of the shot peening system 1. That is, the communication unit 35 constitutes an output unit for outputting the strength of the shot peening process.

[0063] As described above, the strength measurement device 30 takes the AE signal waveform from the sensor device 20 as an input and outputs the strength of the shot peening process based on this AE signal waveform. The strength y output from the strength measurement device 30 satisfies the above formula (4).

[0064] (First Configuration Example)

[0065] Figure 7 The first configuration example of the strength measurement device 30 showing each function of the installed strength measurement device 30 is shown. As Figure 7As shown, the strength measurement device 30 according to the first configuration example includes 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 as physical components. 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 using the power of a battery 51.

[0066] 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 and amplifies the AE signal waveform to output 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.

[0067] 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 prescribed sampling frequency to convert the AE signal waveform into digital data.

[0068] The FPGA 45 is an integrated circuit with a circuit structure of programmable logic gates and executes a prescribed operation corresponding to a program at high speed. The FPGA 45, for example, calculates the effective value at each moment based on the digital data of the AE signal waveform according to Equation (1) and generates time-series data of the effective value. In addition, the operation of the FPGA 45 is controlled by a switch signal received from the switch 53 via the flip-flop 54.

[0069] 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 prescribed 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 prescribed time length L is stored in the memory 52, for example. The FPGA 45 stores the calculated average value of the effective values in the memory 52. In addition, the memory 52 may be built into the FPGA 45.

[0070] The processor 46 is composed of an arithmetic device such as a microcomputer or a PLC. The processor 46 reads the average value of the effective values stored in the memory 52, and calculates the intensity of the shot peening process based on the average value of the effective values. For example, the processor 46 reads the model formula corresponding to the type of the shot medium 2 from the memory 52, and uses this model formula to calculate the intensity corresponding to the average value of the effective values. As the model formula used for the calculation of the intensity, the model formula shown in the above formula (4) is used. That is, the processor 46 constitutes the intensity acquisition unit 34.

[0071] In addition, 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 can also be assigned to either the FPGA 45 or the processor 46. For example, the FPGA 45 can 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. Alternatively, only the generation process of the time series data of the effective values can 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 can 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.

[0072] The communication device 47 is a device that communicates with the external device 40 through 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 the information indicating the calculated intensity of the shot peening 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.

[0073] As described above, in the intensity measurement device 30 according to the first configuration example, the generation process of the time series data of the effective values, which requires a large calculation load, is assigned to the FPGA 45, so that the high-speed measurement of the intensity can be achieved. Moreover, since 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, the miniaturization of the intensity measurement device 30 can be achieved.

[0074] (Second Configuration Example)

[0075] Next, a second configuration example of the intensity measurement device 30 will be described. Figure 8 The second configuration example of the intensity measurement device 30 is shown. As Figure 8As shown, the strength measurement device 30 according to the second configuration example includes 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 as physical components. The charge amplifier 41, the variable gain 42, the filter 43, the AD converter 44, the processor 46, the communication device 47, and the RMS-DC converter 48 are mounted on the same substrate 50 and operate using the power of the battery 51.

[0076] That is, the strength measurement device 30 according to the second configuration example is different from the strength 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 strength measurement device 30 according to the first configuration example, and repeated descriptions will be omitted.

[0077] The RMS-DC converter 48 is a circuit that outputs an output value representing the effective value of the AE signal waveform. For example, the input of the RMS-DC converter 48 is Figure 4 the AE signal waveform shown, and the output of the RMS-DC converter 48 is Figure 5 the effective value that changes with time shown. In the second configuration example, the RMS-DC converter 48 constitutes the time series data generation unit 32.

[0078] In one embodiment, as Figure 8 shown, the RMS-DC converter 48 is arranged between the filter 43 and the AD converter 44, inputs the AE signal waveform output from the filter 43, and outputs an output value representing 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 with 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.

[0079] The processor 46 calculates the average value of the effective value based on the digital data of the effective value 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 value and calculates the average value of the plurality of effective values.

[0080] In addition, the processor 46 calculates the strength of the shot peening treatment based on the calculated average value of the effective value. For example, the processor 46 reads a model formula corresponding to the type of the shot peening medium 2 from the memory 52 and uses the model formula to calculate the strength corresponding to the average value of the effective value. The calculated strength is sent to the external device 40 through the communication device 47.

[0081] As described above, in the intensity measurement device 30 according to the second configuration example, the RMS-DC converter 48 is used to generate the time series data of the effective value, so that the calculation amount of the processor 46 can be reduced. Therefore, the high-speed measurement of the intensity can be realized.

[0082] As described above, in the intensity measurement device 30, the intensity of the shot peening is obtained 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. Therefore, the intensity of the shot peening can be obtained based on the average value of the effective value without using a micrometer to measure the arc height of the test piece. In particular, as shown in Equation (4), the average value of the effective value and the intensity can be expressed by the relationship of a polynomial of one variable. Therefore, the intensity of the shot peening can be calculated based on the average value of the effective value without performing complex calculations. Therefore, the calculation load of the intensity measurement device 30 can be reduced. In addition, the effective value of the AE signal waveform changes with time. Therefore, if the intensity is obtained based on the instantaneous value of the effective value, there is a concern that the output intensity deviates from the true intensity. Therefore, the average value of the effective value is used to infer the intensity, and thus the inferred value of the intensity can be made closer to the true intensity.

[0083] The operator of the shot peening system 1 compares the intensity required to impart the 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 converges within the specified management range. When the difference between the required intensity and the measured intensity converges within the specified management range, the shot peening medium 2 is projected onto the object to be processed under the set projection conditions.

[0084] On the other hand, when the difference between the required intensity and the measured intensity does not converge within the specified management range, the projection conditions of the shot peening device 10 are corrected so that the difference between the required intensity and the measured intensity becomes smaller. For example, when the measured intensity is less than the required intensity, the projection conditions are corrected so that the injection pressure or injection amount of the shot peening medium 2 becomes larger, and the shot peening medium 2 is projected onto the object to be processed under the corrected projection conditions. On the contrary, when the measured intensity is greater than the required intensity, the projection conditions are corrected so that the injection pressure or injection amount of the shot peening medium 2 becomes smaller, and the shot peening medium 2 is projected onto the object to be processed under the corrected projection conditions. As a result, the desired compressive residual stress can be imparted to the object to be processed.

[0085] Next, an intensity measurement method for measuring the intensity of shot peening using the above intensity measurement device 30 will be described. Figure 9 It is a flowchart showing an intensity measurement method according to an embodiment.

[0086] In this method, first, the shot peening medium 2 is projected from the shot peening device 10 onto the surface 21a of the sensor device 20 (step ST1). When the shot peening medium 2 collides with the surface 21a, a part of the strain energy is released as elastic waves along with the deformation or destruction of the collision part 21. The sensor device 20 measures the elastic waves generated by the collision of the shot peening medium 2 and outputs them as an AE signal waveform.

[0087] Next, the waveform acquisition unit 31 of the strength measurement device 30 acquires the AE signal waveform from the sensor device 20 (step ST2). Next, the time series data generation unit 32 generates time series data of the effective values of the AE signal waveform (step ST3). The time series data of the effective values can be generated by the FPGA 45 or the processor 46 by calculating the effective values at each moment based on the above formula (1), or can be generated using the RMS-DC converter 48.

[0088] Next, the average value acquisition unit 33 obtains the average value of the effective values within a specified 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 specified time length L from the time series data of the effective values and calculating the average value of the plurality of effective values.

[0089] Next, the strength acquisition unit 34 obtains the strength of the shot peening based on the average value of the effective values (step ST5). For example, the strength is calculated by the FPGA 45 or the processor 46 applying the average value of the effective values to the above formula (4).

[0090] Next, the communication unit 35 outputs the obtained strength to the external device 40 (step ST6). The external device 40 displays the strength measured by the sensor device 20 on the display device. The operator of the shot peening system 1 sets the projection conditions of the shot peening device 10 based on the displayed strength.

[0091] As described above, the strength measurement device, the strength measurement system, and the strength measurement method according to various embodiments have been described. However, the present invention is not limited to the above embodiments, and various modified forms can be configured without changing the gist of the invention. That is, the above embodiments are for illustrative purposes, and it should be noted that they do not limit the scope of the present invention.

[0092] For example, in the above embodiment, the strength measurement device 30 measures the strength based on the AE signal waveform output from the sensor device 20. However, the strength measurement device 30 can measure the strength based on the AE signal waveform output from any sensor. For example, as Figure 1As shown, when an AE sensor 23 for measuring elastic waves is provided at the nozzle 15 of the shot peening device 10, the intensity measuring device 30 can also measure the intensity of shot peening based on the AE signal waveform output from the AE sensor 23. In this case, the intensity of shot peening can be measured based on the AE signal waveform representing the elastic waves generated at the nozzle 15 when the shot peening medium 2 is projected.

[0093] In addition, in Figure 7 the first configuration example shown, at least a part of the generation process of the time series data of the effective value, the calculation process of the average value of the effective value, and the calculation process of the intensity are assigned to the FPGA 45, but in one embodiment, at least a part of these processes can also be assigned to an ASIC (Application Specific Integrated Circuit).

[0094] In addition, in Figure 8 the second configuration example shown, an RMS-DC converter 48 is used instead of the FPGA 45, but the intensity measuring device 30 can also include both the FPGA 45 and the RMS-DC converter 48, and assign at least a part of the calculation process of the average value of the effective value and the calculation process of the intensity to the FPGA 45.

[0095] In addition, the above various embodiments can be combined within a non-contradictory range.

[0096] [Modes included in the present disclosure]

[0097] The present disclosure includes the modes described in the following items.

[0098] (Item 1) An intensity measuring device according to one mode is connected to a sensor device that outputs a signal waveform related to elastic waves generated by shot peening, and measures the intensity of shot peening based on the signal waveform. The intensity measuring 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 within a specified time length based on the time series data; and an intensity acquisition unit that obtains the intensity of 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 shot peening. In the intensity measuring device according to this mode, since the intensity is obtained based on the average value of the effective value, the intensity of shot peening can be obtained without using a micrometer to measure the arc height of the test piece. Therefore, the intensity can be simply measured in a short time.

[0099] (Item 2) In the intensity measuring device described in Item 1, the intensity acquisition unit may calculate the intensity y based on the following formula (1).

[0100]

Mathematical Expression 7

[0101]

[0102] where a k is a constant and x is the average value of the above effective values.

[0103] As shown in Equation (1), the average value of the effective value and the intensity of the shot peening treatment can be expressed by a polynomial relationship. By calculating the intensity of the shot peening treatment using a simple calculation formula as described above, the calculation load of the intensity can be reduced.

[0104] (Item 3) The intensity measuring device described in Item 1 or 2 may further include a communication unit that sends the intensity to an external device. By sending the intensity to the external device, the amount of data transmitted to the external device can be reduced compared to the case of sending a signal waveform to the external device.

[0105] (Item 4) The intensity measuring device described in any one of Items 1 to 3 may include: an amplifier that constitutes a waveform acquisition unit; an FPGA that constitutes 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 generates time series data of the effective value based on the digital data. To generate time series data of the effective value, a large amount of calculation is required and it takes a long time. By allocating the process of generating time series data of the effective value to the FPGA, the measurement time of the intensity can be shortened.

[0106] (Item 5) In the intensity measuring device described in any item of Item 4, the FPGA may also calculate the average value of the effective values within a specified time length based on the time series data of the effective values. By allocating the process of calculating the average value of the effective values to the FPGA, the measurement time of the intensity can be further shortened.

[0107] (Item 6) In the intensity measuring device described in Item 4 or 5, the amplifier, FPGA, and AD converter may be arranged on the same substrate. In this case, miniaturization of the intensity measuring device can be achieved.

[0108] (Item 7) The strength measurement device described in any one of Items 1 to 3 may also include: an amplifier, which constitutes the waveform acquisition unit; an RMS-DC converter, which constitutes the 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 representing the effective value of the signal waveform that changes over time. The AD converter samples the output value to convert the effective value of the signal waveform into digital data. In this case, since the output value representing the effective value of the signal waveform is output from the RMS-DC converter, the calculation load of the effective value of the signal waveform can be reduced. Thereby, the strength can be measured efficiently.

[0109] (Item 8) The strength measurement device described in Item 7 may also include a processor, which constitutes the average value acquisition unit and the strength acquisition unit. The processor calculates the average value of the effective value within a specified time length based on the digital data, and calculates the strength of the shot peening treatment based on the average value of the effective value. In this case, the strength can be calculated based on the output value output from the RMS-DC converter, so the calculation load of the processor can be reduced.

[0110] (Item 9) The strength 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 peening treatment, and measures the strength of the shot peening treatment based on the above signal waveform. This strength measurement device includes: a waveform acquisition unit that acquires the above signal waveform from the above sensor device; and an output unit that outputs the strength of the above shot peening treatment based on the above signal waveform. The strength y output from the above output unit satisfies the following formula (2).

[0111]

Equation 8

[0112]

[0113] where a k is a constant, and x is the average value of the effective values of the above signal waveform within a specified time length.

[0114] As described above, in the strength measurement device according to this aspect, the strength is obtained based on the average value of the effective value, so the strength can be simply measured in a short time.

[0115] (Item 10) The intensity measurement system according to one aspect includes: a sensor device that outputs a signal waveform related to elastic waves 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 the average value of the effective value within a specified 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. In this intensity measurement device system, the intensity is obtained based on the average value of the effective value, so the intensity can be simply measured in a short time.

[0116] (Item 11) In the intensity measurement device described in Item 10, the sensor device may also include: a collision member having a surface for receiving a shot peening medium; a waveguide member having a first surface in contact with the collision member and a second surface on the opposite side of the first surface, and propagating elastic waves generated by the collision of the shot peening medium from the first surface to the second surface; and an AE sensor that detects the elastic waves propagated to the second surface and outputs a signal waveform. By measuring the elastic waves propagated in the waveguide member using the AE sensor, the AE sensor can be protected, and thus the failure of the AE sensor can be prevented.

[0117] (Item 12) In the intensity measurement device described in Item 10, the sensor device may also include: a waveguide member having a first surface for receiving a shot peening medium and a second surface on the opposite side of the first surface, and propagating elastic waves generated by the collision of the shot peening medium from the first surface to the second surface; and an AE sensor that detects the elastic waves propagated to the second surface and outputs a signal waveform.

[0118] (Item 13) An intensity measurement method according to one aspect includes: a step of acquiring a signal waveform related to elastic waves 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 the average value of the effective value within a specified time length based on the time series data; and a step of obtaining the intensity of the shot peening based on the average value of the effective value. In this intensity measurement method, the intensity is obtained based on the average value of the effective value, so the intensity can be simply measured in a short time.

Claims

1. A strength measuring device connected to a sensor device that outputs a signal waveform related to elastic waves generated by shot peening, and measures the strength of the shot peening based on the signal waveform, The strength measuring device is characterized by comprising: A waveform acquisition unit, which acquires the signal waveform from the sensor device; A time series data generating unit that generates time series data of effective values ​​of the signal waveform; an average value acquisition unit that obtains an average value of the effective values ​​within a predetermined time length based on the time series data; and The intensity acquisition unit obtains the intensity of the shot peening based on an average value of the effective values.

2. The strength measuring device according to claim 1, characterized in that: The intensity acquisition unit calculates the intensity y based on the following formula (1): 【Formula 1】 Among them, a k is a constant and x is the average of the effective values.

3. The strength measuring device according to claim 1 or 2, characterized in that: Also available: The communication unit sends the strength to an external device.

4. The strength measuring device according to any one of claims 1 to 3, characterized in that: have: an amplifier, constituting the waveform acquisition unit; FPGA, constituting the time series data generating unit; and 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. The FPGA calculates the effective value at each time point based on the digital data, and generates time series data of the effective value.

5. The strength measuring device according to claim 4, characterized in that: The FPGA calculates an average value of the effective value within the prescribed time length based on the effective value at each time point.

6. The strength measuring device according to claim 4 or 5, characterized in that: The amplifier, the FPGA and the AD converter are configured on the same substrate.

7. The strength measuring device according to any one of claims 1 to 3, characterized in that: have: an amplifier, constituting the waveform acquisition unit; An RMS-DC converter constituting the time series data generating unit; and AD converter, The amplifier amplifies the signal waveform output from the sensor device, The RMS-DC converter inputs the signal waveform and outputs an output value representing an effective value of the signal waveform that changes with time, The AD converter samples the output value to convert the effective value of the signal waveform into digital data.

8. The strength measuring device according to claim 7, characterized in that: Also available: a processor, constituting the average value acquisition unit and the intensity acquisition unit, The processor calculates an average value of the effective values ​​within the prescribed time length based on the digital data, and calculates the intensity of the shot peening based on the average value of the effective values.

9. A strength measuring device connected to a sensor device that outputs a signal waveform related to elastic waves generated by shot peening, and measures the strength of the shot peening based on the signal waveform. The strength measuring device is characterized by comprising: a waveform acquisition unit that acquires the signal waveform from the sensor device; and an output unit that outputs the intensity of the shot peening process based on the signal waveform, The intensity y output from the output unit satisfies the following formula (2): 【Formula 2】 in, a k is a constant, and x is the average value of the effective value of the signal waveform within a specified time length.

10. A strength measurement system, characterized in that: have: a sensor device that outputs a signal waveform related to elastic waves generated by shot peening; A waveform acquisition unit, which acquires the signal waveform from the sensor device; A time series data generating unit that generates time series data of effective values ​​of the signal waveform; an average value acquisition unit that obtains an average value of the effective values ​​within a predetermined time length based on the time series data; as well as The intensity acquisition unit obtains the intensity of the shot peening based on an average value of the effective values.

11. The strength measurement system according to claim 10, characterized in that: The sensor device comprises: an impact component having a surface that receives the peening medium; a waveguide member having a first surface in contact with the collision member and a second surface opposite to the first surface, and transmitting elastic waves generated by the collision of the shot peening medium from the first surface to the second surface; and The AE sensor detects the elastic wave propagating to the second surface and outputs the signal waveform.

12. The strength measurement system according to claim 10, characterized in that: The sensor device comprises: a waveguide member having a first surface for receiving the shot peening medium and a second surface on the opposite side of the first surface, and transmitting elastic waves generated by the collision of the shot peening medium from the first surface to the second surface; and The AE sensor detects the elastic wave propagating to the second surface and outputs the signal waveform.

13. A strength measurement method, characterized in that: include: a step of acquiring, from a sensor device, a signal waveform associated with an elastic wave generated by shot peening; A step of generating time series data of effective values ​​of the signal waveform; A step of obtaining an average value of the effective values ​​within a predetermined time length based on the time series data; as well as A step of obtaining the intensity of the shot peening based on the average value of the effective values.

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