Shot peening system and shot peening method

Abstract

A shot blasting system according to one aspect of the present invention includes a shot blasting device that performs shot blasting of a shot medium, a measurement device that receives the shot medium projected from the shot blasting device and outputs a signal waveform related to a wave generated by collision of the shot medium, and a control device that controls the shot blasting device. The control device includes a machining condition acquisition section that acquires a required mechanical strength, a control section that controls the shot blasting device to perform shot blasting of the measurement device under a first projection condition, a strength analysis section that analyzes the signal waveform output from the measurement device by the shot blasting of the measurement device to thereby acquire a measured mechanical strength, and a correction section that corrects the projection condition of the shot blasting device from the first projection condition to a second projection condition to thereby reduce a difference between the required mechanical strength and the measured mechanical strength.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a shot processing system and a shot processing method. BACKGROUND

[0002] In shot processing such as shot blast processing and shot peening processing, a shot processing device that projects a shot medium (projecting material) toward a processing target is used. In the case where shot processing is performed using the shot processing device, it is required that the shot medium collide with the processing target with an appropriate intensity in a manner that the processing target becomes an appropriate processed state corresponding to its use.

[0003] As a method of measuring the projection intensity of the shot medium, for example, the technology described in Patent Literature 1 is known. In Patent Literature 1, it is described that an elastic wave generated when the shot medium collides with a circular plate is converted into a high-frequency electric signal, and the shot collision amount and kinetic energy are detected based on a counter output voltage and a peak voltage obtained by analyzing the high-frequency electric signal.

[0004] Patent Literature 1: Japanese Patent Application Laid-Open No. 04-019071

[0005] In the device described in Patent Literature 1, the projection amount and the projection intensity of the shot medium are adjusted by changing the projection conditions of the shot processing device. However, as the projection conditions of the shot processing, there are multiple parameters such as the injection pressure of the shot medium, the injection amount of the shot medium, the kind (particle diameter and hardness) of the shot medium, the distance from the nozzle to the processing target, the diameter of the nozzle, and the like, and thus it is not easy to uniquely determine appropriate projection conditions for processing the processing target with a desired intensity. In the case where appropriate projection conditions cannot be set, the processing target cannot be processed with a desired intensity.

[0006] Therefore, it is required to determine appropriate projection conditions for processing the processing target with a desired intensity. SUMMARY

[0007] A shot processing system according to one aspect includes a shot processing device, a measurement device, and a control device. The shot processing device performs shot processing that projects a shot medium. The measurement device receives the shot medium projected from the shot processing device and outputs a signal waveform related to a fluctuation generated by a collision of the shot medium. The control device controls the shot processing device. The control device includes a processing condition acquisition unit, a control unit, a strength analysis unit, and a correction unit. The processing condition acquisition unit acquires a required mechanical strength that indicates a strength of the shot processing to be performed on a processing target. The control unit controls the shot processing device to perform the shot processing on the measurement device in a first projection condition. The strength analysis unit analyzes the signal waveform output from the measurement device by the shot processing on the measurement device, thereby acquiring a measured mechanical strength that indicates a strength of the shot processing on the measurement device. The correction unit corrects the projection condition of the shot processing device from the first projection condition to a second projection condition so that a difference between the required mechanical strength and the measured mechanical strength is reduced.

[0008] In the shot processing system according to the aspect, when the shot medium is projected from the shot processing device to the measurement device in the first projection condition, the signal waveform related to the fluctuation generated by the collision of the shot medium is output from the measurement device. By analyzing the signal waveform, the measured mechanical strength that indicates the strength of the shot processing on the measurement device is acquired. Further, the first projection condition is corrected to the second projection condition so that the difference between the required mechanical strength and the measured mechanical strength is reduced. By such a correction, the projection condition of the shot processing device can be brought close to the projection condition for obtaining the required mechanical strength. Therefore, according to the aspect, the appropriate projection condition for processing the processing target at the required mechanical strength can be determined.

[0009] In another aspect, a shot processing method using a shot processing device that performs shot processing that projects a shot medium is provided. The shot processing method includes a step of acquiring a required mechanical strength that indicates a strength of the shot processing to be performed on a processing target; a step of controlling the shot processing device to perform the shot processing on a measurement device in a first projection condition; a step of outputting a signal waveform related to a fluctuation generated by a collision of the shot medium with the measurement device; a step of acquiring a measured mechanical strength that indicates a strength of the shot processing on the measurement device by analyzing the signal waveform; and a step of correcting a projection condition of the shot processing device from the first projection condition to a second projection condition so that a difference between the required mechanical strength and the measured mechanical strength is reduced.

[0010] As described above, according to the shot processing method according to the aspect and the embodiments, the projection condition of the shot processing device can be brought close to the projection condition for obtaining the required mechanical strength. Therefore, the appropriate projection condition for processing the processing target at the required mechanical strength can be determined.

[0011] According to various aspects of the present disclosure, it is possible to determine appropriate projection conditions for processing a target object with a desired intensity. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 is a diagram briefly showing a shot processing system according to an embodiment.

[0013] Figure 2 is a block diagram showing a functional configuration of a shot processing system.

[0014] Figure 3 is a diagram showing one example of an AE signal waveform measured by an AE sensor.

[0015] Figure 4 is a graph showing a relationship between an AE parameter and a mechanical intensity.

[0016] Figure 5 is a graph showing a relationship between an AE parameter and a shot medium ejection pressure.

[0017] Figure 6 is a flowchart showing a shot processing method according to an embodiment.

[0018] Figure 7 is a flowchart showing a method of monitoring an abnormality of a shot processing device.

[0019] EXPLANATION OF REFERENCE NUMERALS

[0020] 1... shot processing system; 10... shot processing device; 15... nozzle; 16... AE sensor (second AE sensor); 20... measurement device; 20a... projection surface; 21... AE sensor; 30... control device; 34... control section; 47... intensity analysis section; 49... correction section; 52... projection condition analysis section; 54... alarm output section; 55... correction section (second correction section); S... shot medium. DETAILED DESCRIPTION

[0021] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. Furthermore, in the following description, the same or equivalent elements are denoted by the same reference numerals, and repetitive description will not be repeated. The dimensional ratios of the drawings are not necessarily consistent with the dimensional ratios of the description.

[0022] Figure 1 is a diagram briefly showing a shot processing system according to an embodiment. Figure 2 is a block diagram showing a functional configuration of a shot processing system according to an embodiment. Figure 1 and Figure 2The shot blasting system 1 shown determines the projection conditions of the shot media in order to process the work object with a desired intensity, and projects the shot media with the determined projection conditions. Further, in the present specification, the process of projecting the shot media from the shot blasting device is referred to as "shot blasting". The shot blasting includes shot blasting for the purpose of descaling, deburring, and surface roughness adjustment, and shot peening for the purpose of imparting residual compressive stress to the work object.

[0023] As shown in Figure 1 The shot blasting system 1 shown in the figure is provided with a shot blasting device 10, a measuring device 20, and a control device 30. The shot blasting device 10 processes the surface of the work object by projecting the shot media against the work object so that the shot media collides with the work object. For example, the shot blasting device 10 is a shot peening device that imparts compressive residual stress to the surface of the work object. As the work object subjected to shot blasting by the shot blasting device 10, for example, automobile parts such as cylinder heads and crankshafts, gears, molds, and the like are exemplified, but the work object is not limited to these. Compressive residual stress is imparted to the surface of the work object by shot blasting, whereby the fatigue characteristics of the work object are improved. The compressive residual stress to be imparted to the work object is determined in accordance with the use of the work object. The magnitude of the compressive residual stress imparted to the work object depends on the intensity of the shot blasting (the collision intensity of the shot media).

[0024] Figure 1 The shot blasting device 10 shown is a direct pressure type shot peening device. Further, the shot blasting device 10 can also be an aspiration type or a gravity type shot peening device. As the shot media S to be projected against the work object, for example, a steel ball is used. The particle diameter of the steel ball is appropriately selected in accordance with the compressive residual stress to be imparted to the work object.

[0025] As shown in Figure 1 The shot blasting device 10 shown in the figure is provided with a shot media tank 11, a shot media supply device 12, a pressurizing tank 13, a compressor 14, and a nozzle 15. The shot media tank 11 stores the shot media S. The shot media tank 11 is connected to the pressurizing tank 13 via the shot media supply device 12. A lift valve 64 capable of being opened and closed is provided between the shot media supply device 12 and the pressurizing tank 13. By opening the lift valve 64, the shot media S stored inside the shot media tank 11 is supplied to the pressurizing tank 13 via the shot media supply device 12.

[0026] The compressor 14 generates compressed air and supplies the compressed air to the pressurizing tank 13 and the nozzle 15. The compressor 14 is connected to one end of a pipe 61. The other end of the pipe 61 is connected to a pipe 63 described later. A pipe 62 is branched from a position between the one end and the other end of the pipe 61. The pipe 62 is connected to an air flow inlet 13A of the pressurizing tank 13. An air flow adjusting valve 68 is provided in the pipe 62. The air flow adjusting valve 68 adjusts the flow rate of the compressed air flowing in the pipe 62. After the air flow adjusting valve 68 is opened, the compressed air from the compressor 14 is supplied to the pressurizing tank 13 via the pipe 61 and the pipe 62. By supplying the compressed air from the compressor 14 to the pressurizing tank 13, the inside of the pressurizing tank 13 is pressurized.

[0027] The pressurizing tank 13 has a shot flow outlet 13B from which the shot media S flows out. A gate 60 that can be opened and closed is provided at the shot flow outlet 13B. The pipe 63 is connected to the shot flow outlet 13B via the gate 60. A shot amount adjusting valve 65 that adjusts the amount of the shot media S 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 of the pipe 61 and the pipe 63 constitutes a mixing portion 25A that mixes the shot media S supplied from the pressurizing tank 13 and the compressed air supplied from the compressor 14. This mixing portion 25A is located at a position downstream of a branch portion 25B at which the pipe 62 is branched from the pipe 61, in the flow direction of the compressed air.

[0028] An air flow adjusting valve 66 is provided at a position between the mixing portion 25A and the branch portion 25B in the pipe 61. The air flow adjusting 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 adjusting valve 66 is mixed with the shot media S supplied from the pressurizing tank 13 at the mixing portion 25A, and is delivered to the nozzle 15.

[0029] The nozzle 15 is provided at the front end portion of the pipe 63, and ejects the shot media S supplied from the pressurizing tank 13 together with the compressed air as a solid-gas two-phase flow. The nozzle 15 is disposed inside a housing 70. The housing 70 divides a space for processing a treatment target, that is, a processing chamber 70s. In the case where the treatment target is subjected to shot processing, the treatment target is disposed inside the processing chamber 70s, and the shot media S is projected from the nozzle 15 toward the treatment target inside the processing chamber 70s, and the shot media S collides with the treatment target.

[0030] Furthermore, although in the embodiment described above Figure 1Although not illustrated, the shot blasting device 10 can further include a dust collecting device, a classifying device, and a circulating device in order to reuse the shot media S used. The dust collecting device is connected to the processing chamber 70s via the classifying device, and transfers the shot media S and the chips of the workpiece, which have fallen to the lower portion of the processing chamber 70s, to the classifying device by suction. The classifying device is, for example, a cyclone type classifying device, and classifies the shot media S and the chips of the workpiece into particles that can be reused as the shot media S and particles that cannot be reused as the shot media S. The circulating device returns the shot media S that can be reused to the shot media tank 11 via a bucket elevator, a screw conveyor, a separator, or the like.

[0031] The shot blasting device 10 further includes an AE sensor (second AE sensor) 16, an AD conversion section 17, and a communication section 18 (see FIG. 1). Figure 2 The AE sensor 16 is fixed to the nozzle 15, measures acoustic emission (AE) generated when the shot media S is projected from the nozzle 15 of the shot blasting device 10, and outputs a signal waveform (hereinafter referred to as an "AE signal waveform") related to the measured AE. The AE signal waveform is a signal waveform related to an elastic wave such as a vibration or a sound wave generated when the shot media S is shot through the nozzle 15. The AE signal waveform includes, for example, an amplitude, a duration, an AE count, a rise time, an AE count rate, and an average frequency as characteristic parameters associated with the intensity of the shot blasting.

[0032] The AD conversion section 17 converts the AE signal waveform output from the AE sensor 16 into digital data and outputs the same. The communication section 18 is a communication module capable of wireless communication such as LAN, Bluetooth (registered trademark), Wifi, or the like. The communication section 18 receives the digital data of the AE signal waveform measured by the AE sensor 16 from the AD conversion section 17, and transmits the digital data to the control device 30 through wireless communication.

[0033] As described above, the shot peening medium S projected from the nozzle 15 of the shot peening apparatus 10 collides with the workpiece. The shot peening medium S exerts a striking force on the surface of the workpiece upon impact, thereby generating a reaction force against this force on the workpiece, resulting in compressive residual stress imposed on it. The compressive residual stress imposed on the workpiece depends on its intended use. To impose the required compressive residual stress on the workpiece, it is necessary to perform shot peening with an appropriate intensity. In the following description, mechanical intensity is used as an indicator to quantitatively represent the intensity of shot peening. Mechanical intensity is equivalent to the arc height at which a hardening time-arc height saturation curve is constructed by measuring the arc height value after shot peening a test piece at any time, and the arc height increase rate read from this saturation curve becomes within 10%. In the following description, the mechanical intensity used to impose the required compressive residual stress on the workpiece is referred to as "required mechanical intensity." That is, required mechanical intensity represents the intensity of shot peening to be performed on the workpiece.

[0034] In the shot peening system 1, to confirm whether the mechanical strength of the shot peening treatment matches the required mechanical strength, the mechanical strength of the shot peening treatment is measured by performing shot peening on the measuring device 20 before shot peening the object to be treated. Furthermore, the measured mechanical strength is periodically checked to ensure it matches the required mechanical strength. The mechanical strength measurement is performed once or multiple times, for example, before shot peening the object to be treated.

[0035] The measuring device 20 receives the shot peening medium S projected from the shot peening treatment device 10 at the projection surface 20a, and outputs a signal related to the wave generated by the collision of the shot peening medium S. The wave is a general term for the wave generated when the shot peening medium S collides with the projection surface 20a, and includes concepts such as elastic waves, vibrations, ultrasonic waves, and electromagnetic waves. Figure 2 As shown, the measuring device 20 includes an AE sensor 21, an AD converter 22, and a communication unit 23. The AE sensor 21 measures the AE generated when the shot peening medium S projected from the shot peening treatment device 10 collides with the projection surface 20a of the measuring device 20, and outputs a signal waveform related to the measured AE. Figure 3 An example of an AE signal waveform measured by AE sensor 21 upon impact with the shot peening medium S is shown. The AE signal waveform is a signal waveform related to the AE (elastic wave) generated due to the impact of the shot peening medium S on the projection surface 20a.

[0036] The AD conversion section 22 converts an AE signal waveform output from the AE sensor 21 into digital data and outputs the same. The communication section 23 is a communication module capable of wireless communication such as LAN, Bluetooth (registered trademark), Wifi, and the like. The communication section 23 receives digital data of an AE signal waveform measured by the AE sensor 21 from the AD conversion section 22 and transmits the digital data to the control device 30 through wireless communication.

[0037] The control device 30 is a computer equipped with a processor, a storage device, an input device, a display device, a communication device, and the like, and controls the operation of the entire shot processing system 1. The control device 30, for example, loads a program stored in the storage device and executes the loaded program by the processor, whereby various functions described later are realized. In the control device 30, an operator can perform an input operation of an instruction and the like using the input device in order to manage the shot processing device 10, and in addition, the operation status of the shot processing device 10 can be visually displayed by the display device.

[0038] The control device 30 is communicably connected to the shot processing device 10 and the measuring device 20. The control device 30 determines a projection condition of the shot medium S of the shot processing device 10 and controls the shot processing device 10 so that the shot medium S is projected with the determined projection condition. Here, the projection condition is a condition set to the shot processing device 10 in order to project the shot medium S, and for example, the injection pressure of the shot medium S and the injection amount of the shot medium S can be cited.

[0039] As shown in Fig. 1, the control device 30 is communicably connected to the shot processing device 10 and the measuring device 20. The control device 30 determines a projection condition of the shot medium S of the shot processing device 10 and controls the shot processing device 10 so that the shot medium S is projected with the determined projection condition. Here, the projection condition is a condition set to the shot processing device 10 in order to project the shot medium S, and for example, the injection pressure of the shot medium S and the injection amount of the shot medium S can be cited. Figure 2 As a functional structural element, the control device 30 is equipped with a projection condition determination section 31, a projection condition correction section 32, an equipment monitoring section 33, a control section 34, and a storage section 35. The projection condition determination section 31 determines a projection condition for obtaining a required mechanical strength using a correlation between the projection condition of the shot medium S and the mechanical strength.

[0040] The projection condition determination section 31 includes a processing condition acquisition section 41 and a determination section 42. The processing condition acquisition section 41 acquires a required mechanical strength of a processing target as a processing condition. The processing condition acquisition section 41 can also acquire a management range of the mechanical strength and information (particle diameter, hardness, and the like) related to the shot medium on the basis of the required mechanical strength. These processing conditions can be input by an operator of the shot processing device 10, for example, or can be stored in the storage section 35 in advance. The processing condition acquisition section 41 saves the acquired processing condition in the storage section 35.

[0041] The decision unit 42 decides a projection condition for obtaining a required mechanical strength based on the machining condition of the processing target obtained by the machining condition acquisition unit 41. There is a correlation between the projection condition of the shot blasting device 10 and the mechanical strength, and a model formula indicating the correlation between the projection condition of the shot blasting device 10 and the mechanical strength is stored in advance in the storage unit 35 of the control device 30. The decision unit 42 decides the first projection condition as the projection condition corresponding to the required mechanical strength obtained by the machining condition acquisition unit 41 using the model formula stored in the storage unit 35. The decision unit 42 stores the decided first projection condition in the storage unit 35.

[0042] The control unit 34 controls the shot blasting device 10 so that the shot blasting medium is projected at the first projection condition decided by the projection condition decision unit 31. For example, the control unit 34 controls the operation of the compressor 14, the opening and closing of the gate 60, the opening degree of the shot amount adjustment valve 65, the opening degree of the air flow adjustment valve 66, and the opening degree of the air flow adjustment valve 68 of the shot blasting device 10, thereby causing the shot blasting medium S to be projected at the projection pressure and the projection amount set as the first projection condition from the shot blasting device 10. The shot blasting medium S projected from the shot blasting device 10 collides with the projection surface 20a of the measuring device 20. The measuring device 20 measures the AE generated by the collision of the shot blasting medium S and outputs an AE signal waveform.

[0043] The projection condition correction unit 32 analyzes the AE signal waveform measured by the measuring device 20 to obtain a measured value of the mechanical strength (hereinafter referred to as "measured mechanical strength"), and corrects the projection condition of the shot blasting device 10 based on the difference between the measured mechanical strength and the required mechanical strength. As shown in FIG. 1, the projection condition correction unit 32 includes a signal reception unit 46, a strength analysis unit 47, a comparison unit 48, and a correction unit 49. The signal reception unit 46 receives digital data of the AE signal waveform measured by the AE sensor 21 from the communication unit 23. Figure 2

[0044] The strength analysis unit 47 analyzes the AE signal waveform received by the signal reception unit 46 and calculates the mechanical strength when the shot blasting is performed at the first projection condition. For example, the strength analysis unit 47 obtains an AE parameter from the AE signal waveform. As the AE parameter, for example, the amplitude, the duration, the AE count, or the rise time of the AE signal waveform is used. In addition, the peak value, the average value, or the effective value of the AE signal waveform can also be used as the AE parameter.

[0045] Figure 4 is a graph in which the AE parameter and the mechanical strength are plotted for each kind of shot blasting medium. As shown in FIG. 2, there is a correlation between the AE parameter and the mechanical strength. The strength analysis unit 47 analyzes the AE signal waveform received by the signal reception unit 46 to obtain the AE parameter and the measured mechanical strength. Figure 4 Figure 4 ​​The coordinate diagram shown draws an approximate straight line or an approximate curve representing the relationship between the AE parameter and the mechanical strength of the shot processing, and generates a model formula representing the correlation between the AE parameter and the shot processing according to each kind of the shot medium based on the approximate straight line or the approximate curve. Then, the strength analysis section 47 calculates the mechanical strength corresponding to the AE parameter of the AE signal waveform received by the signal receiving section 46 based on the generated model formula. The mechanical strength thus calculated is a measured mechanical strength found from the measurement value of the measuring device 20. The strength analysis section 47 saves the measured mechanical strength in the storage section 35.

[0046] The comparison section 48 compares the required mechanical strength and the measured mechanical strength, judges whether the difference between the required mechanical strength and the measured mechanical strength converges within the designated management range, and outputs information representing the judgment result to the correction section 49.

[0047] In a case where the comparison section 48 judges that the difference between the required mechanical strength and the measured mechanical strength does not converge within the designated management range, the correction section 49 corrects the projection condition of the shot processing device 10 from the first projection condition to a second projection condition so as to make the difference between the required mechanical strength and the measured mechanical strength smaller. For example, there is a tendency that the more the shot pressure or the shot amount of the shot medium S is increased, the greater the mechanical strength of the shot processing becomes. Therefore, for example, in a case where the measured mechanical strength is smaller than the required mechanical strength, the correction section 49 sets the second projection condition in which the shot pressure or the shot amount is higher than the shot pressure or the shot amount designated in the first projection condition. Also, the correction section 49 saves the second projection condition as the corrected projection condition in the storage section 35.

[0048] The control section 34 controls the shot processing device 10 so that the shot medium S is projected toward the processing target object in the second projection condition corrected by the correction section 49. By projecting the shot medium S in the second projection condition, it is possible to make the mechanical strength of the shot processing close to the required mechanical strength. Therefore, it is possible to impart the desired compressive residual stress to the processing target object.

[0049] The equipment monitoring section 33 detects an abnormality of the shot processing device 10, such as Figure 2 As shown, the equipment monitoring section 33 includes a signal receiving section 51, a projection condition analysis section 52, an abnormality judgment section 53, an alarm output section 54, and a correction section (second correction section) 55. The signal receiving section 51 receives digital data of the AE signal waveform measured by the AE sensor 16 of the shot processing device 10 from the communication section 18.

[0050] The projection condition analysis section 52 analyzes the AE signal waveform received by the signal receiving section 51, and acquires the projection condition of the shot processing device 10 at the time when the shot medium S is projected. First, the projection condition analysis section 52 acquires the AE parameter from the AE signal waveform.

[0051] Figure 5 is a coordinate graph that depicts the relationship between the AE parameter and the projection pressure of the shot media S as one of the projection conditions, for each kind of shot media. As shown in Figure 5 , there is a correlation between the projection pressure and the AE parameter. The projection condition analysis section 52 draws an approximate straight line or an approximate curve that represents the relationship between the projection pressure and the AE parameter in the coordinate graph shown in Figure 5 , and generates a model formula that represents the correlation between the projection pressure and the AE parameter for each kind of shot media, based on the approximate straight line or the approximate curve. Also, the intensity analysis section 47 calculates the projection pressure (projection condition) that corresponds to the AE parameter of the AE signal waveform received by the signal receiving section 51, based on the generated model formula. In addition, the projection condition analysis section 52 can also calculate the projection pressure that corresponds to the AE parameter of the AE signal waveform received by the signal receiving section 51, based on a model formula that represents the correlation between the projection pressure and the AE parameter. It can be said that the thus calculated projection condition is a measured value of the projection condition calculated from the measurement value of the AE sensor 21 (hereinafter, referred to as "measured projection condition"). The projection condition analysis section 52 stores the calculated measured projection condition in the storage section 35.

[0052] The abnormality determination section 53 compares the projection condition set for the shot blasting device 10 (for example, the first projection condition or the second projection condition) (hereinafter, referred to as "set projection condition") with the measured projection condition. When there is a difference between the set projection condition and the measured projection condition, for example, a defective condition such as a pipe opening of the shot blasting device 10 is generated, the actual projection condition of the shot blasting device 10 can deviate from the set projection condition. Therefore, when the difference between the set projection condition and the measured projection condition exceeds a prescribed threshold value, the abnormality determination section 53 outputs abnormality detection information that indicates that an abnormality has occurred in the shot blasting device 10 to the alarm output section 54. The alarm output section 54 outputs an alarm if it receives the abnormality detection information from the abnormality determination section 53. The output method of the alarm is arbitrary as long as it can notify the operator of the shot blasting device 10 of the alarm, but for example, the alarm output section 54 can visually display information that indicates the occurrence of an abnormality on the display device of the control device 30, or can transmit information that indicates the occurrence of an abnormality to the computer terminal of the operator. Thus, the operator of the shot blasting device 10 can be notified of the abnormality of the shot blasting device 10 as early as possible.

[0053] After the abnormality detection information is output by the abnormality judging section 53, the correction section 55 corrects the projection condition of the shot processing device 10. For example, in a case where the shot pressure of the measured projection condition is smaller than the shot pressure of the set projection condition, the shot pressure of the set projection condition is increased. Thereby, it is possible to make the actual projection condition of the shot processing device 10 close to the target projection condition. Further, in a case where the measured projection condition is smaller than the set projection condition, it is possible to make the actual projection condition of the shot processing device 10 close to the target projection condition by increasing the shot amount of the set projection condition. Figure 2 In the embodiment shown in the drawing, the device monitoring section 33 is provided with both the alarm output section 54 and the correction section 55, but the device monitoring section 33 can be provided with only one of the alarm output section 54 and the correction section 55.

[0054] As explained above, in the shot processing system 1 related to the above-described embodiment, in a case where the shot processing device 10 projects the shot medium S toward the measuring device 20 in the first projection condition, the AE signal waveform generated by the collision of the shot medium S is output from the measuring device 20. Further, the measured mechanical strength is calculated by analyzing the AE signal waveform. Further, the projection condition of the shot processing device 10 is corrected from the first projection condition to the second projection condition so as to make the difference between the required mechanical strength and the measured mechanical strength smaller. By performing the shot processing of the processing target object in the second projection condition after the correction, it is possible to impart the desired compressive residual stress to the processing target object.

[0055] Next, a shot processing method of a processing target object using the above-described shot processing system 1 will be explained. Figure 6 is a flowchart showing a shot processing method related to one embodiment.

[0056] In this method, first, the processing condition acquisition section 41 of the control device 30 acquires the required mechanical strength (step ST1). The required mechanical strength can be input by an operator of the shot processing device 10, or can be read from information stored in advance in the storage section 35. Further, in step ST1, the allowable range (tolerance) of the mechanical strength can also be acquired on the basis of the required mechanical strength.

[0057] Next, the processing condition acquisition section 41 acquires information related to the shot medium S (step ST2). The information related to the shot medium includes, for example, the particle diameter and hardness of the shot medium S. Next, the decision section 42 decides the projection condition of the shot processing device 10 on the basis of the required mechanical strength and the information related to the shot medium (step ST3). The projection condition of the shot processing device 10 includes, for example, the shot pressure and shot amount of the shot medium S. The decision section 42 decides the projection condition corresponding to the required mechanical strength as the first projection condition, for example, using a model formula showing the correlation between the projection condition of the shot processing device 10 and the mechanical strength.

[0058] Next, the first projection condition is set to the shot blasting device 10 (step ST4). Here, for the first projection condition, manual input by an operator using an input device or setting by the control unit 34 transmitting the decided first projection condition to the shot blasting device 10 can be performed.

[0059] Next, the shot blasting device 10 projects the shot medium S to the measuring device 20 arranged in the processing chamber 70s in the first projection condition (step ST5). The shot medium S projected from the shot blasting device 10 collides with the projection surface 20a of the measuring device 20. The measuring device 20 measures the elastic wave generated by the collision of the shot medium S and transmits the AE signal waveform relating to the measured elastic wave to the control device 30 through wireless communication. The signal receiving unit 46 acquires the AE signal waveform output from the AE sensor 21 of the measuring device 20 (step ST6).

[0060] Next, the strength analysis unit 47 analyzes the AE signal waveform to acquire the AE parameter (step ST7). In addition, the strength analysis unit 47 acquires the measured mechanical strength corresponding to the AE waveform signal acquired in step ST6 using a model formula indicating the correlation between the AE parameter and the mechanical strength (step ST8).

[0061] Next, the comparison unit 48 compares the required mechanical strength acquired in step ST1 and the measured mechanical strength calculated in step ST8 to determine whether the difference between the measured mechanical strength and the required mechanical strength converges within the management range (step ST9). That is, when the measured mechanical strength is below the upper limit value of the management range of the required mechanical strength and above the lower limit value of the management range of the required mechanical strength, the comparison unit 48 determines that the difference between the measured mechanical strength and the required mechanical strength converges within the management range. In the case where it is determined that the measured mechanical strength is outside the management range, the correction unit 49 calculates the difference between the required mechanical strength and the measured mechanical strength (step ST10).

[0062] Next, the correction unit 49 corrects the projection condition so that the difference between the required mechanical strength and the measured mechanical strength becomes smaller (step ST11). For example, in the case where the measured mechanical strength is smaller than the required mechanical strength, the projection condition of the shot blasting device 10 is corrected to a second projection condition including a higher projection pressure or projection amount than the projection pressure or projection amount of the first projection condition. The greater the difference between the required mechanical strength and the measured mechanical strength, the greater the correction amount of the projection pressure or projection amount.

[0063] Next, the second projection condition corrected is set to the shot processing device 10 (step ST4), and the shot processing device 10 projects the shot medium S to the measuring device 20 with the corrected second projection condition (step ST5). Further, the steps ST4 to ST11 are repeated until the difference between the measured mechanical strength and the required mechanical strength converges within the management range.

[0064] In a case where the measured mechanical strength converges within the management range, the measuring device 20 is taken out from the processing chamber 70s, and the processing target object is arranged in the processing chamber 70s. Further, the shot processing device 10 projects the shot medium S to the processing target object with the set projection condition (step ST12). Thus, the shot processing of the required mechanical strength is performed on the processing target object. As a result, the desired compressive residual stress is imparted to the processing target object.

[0065] Next, the method for monitoring the abnormality of the shot processing device 10 will be described with reference to Figure 7 to the method for monitoring the abnormality of the shot processing device 10. Figure 7 is a flowchart showing the method for monitoring the abnormality of the shot processing device 10. Figure 7 The method shown in Figure 6 The method shown in

[0066] In the method, first, the projection condition is set to the shot processing device 10 (step ST21). The projection condition set in the step ST21 can be the first projection condition decided by the projection condition deciding section 31, or the second projection condition corrected by the projection condition correcting section 32. Next, the shot processing device 10 projects the shot medium S with the set projection condition (step ST22). At this time, the shot medium S passes through the nozzle 15 of the shot processing device 10, and thus the elastic wave such as the acoustic wave or the vibration is generated around the nozzle 15.

[0067] Next, the AE sensor 16 of the shot processing device 10 measures the elastic wave generated at the time of the projection of the shot medium S, and outputs the AE signal waveform related to the measured elastic wave. The signal receiving section 51 acquires the AE signal waveform output from the AE sensor 16 (step ST23). Next, the projection condition analyzing section 52 analyzes the AE signal waveform received by the signal receiving section 51, and acquires the AE parameter corresponding to the AE signal waveform (step ST24). Next, the projection condition analyzing section 52 calculates the projection condition corresponding to the AE waveform signal using the model formula showing the correlation between the AE parameter and the projection condition (step ST25). The projection condition calculated in the step ST25 is the measured projection condition calculated from the measured value of the AE sensor 21.

[0068] Next, the anomaly detection unit 53 compares the set projection conditions set in step ST21 with the measured projection conditions calculated in step ST25, and determines whether the difference between the set projection conditions and the measured projection conditions is within the allowable range (step ST26). When the difference between the set projection conditions and the measured projection conditions is below a predetermined threshold, the anomaly detection unit 53 determines that the difference is within the allowable range. If the difference between the set projection conditions and the measured projection conditions is within the allowable range, it is determined that the shot peening apparatus 10 is operating normally, and the series of processes ends.

[0069] On the other hand, if the difference between the set projection conditions and the measured projection conditions exceeds a predetermined threshold, the anomaly judgment unit 53 outputs anomaly detection information. Along with the output of this anomaly detection information, the alarm output unit 54 outputs an alarm (step ST27). By outputting this alarm, the anomaly of the shot peening equipment 10 can be reported to the operator of the shot peening equipment 10 as early as possible.

[0070] Furthermore, after the anomaly detection unit 53 outputs anomaly detection information, the correction unit 55 can also correct the projection conditions of the shot peening device 10. For example, if the injection pressure calculated in step ST25 is less than the injection pressure set in step ST21, by increasing the injection pressure of the shot peening device 10, the actual injection pressure of the shot peening device 10 can be made closer to the injection pressure of the target.

[0071] The shot peening system and shot peening method involved in various embodiments have been described above, but various modifications can be made without changing the spirit of the invention, without being limited to the above embodiments.

[0072] For example, in Figure 2 In the shot peening system 1 shown, the control device 30 includes an equipment monitoring unit 33 for detecting abnormalities in the shot peening device 10, but the control device 30 may not necessarily include an equipment monitoring unit 33. By including at least a projection condition determination unit 31 and a projection condition correction unit 32, it is possible to determine the projection conditions for shot peening the object to be treated with the required mechanical strength.

[0073] Further, in the above-described embodiment, the projection condition analysis section 52 of the device monitoring section 33 calculates the measured projection condition by analyzing the AE signal waveform output from the AE sensor 16, but as long as the measured projection condition can be calculated, the AE signal waveform from the AE sensor 16 need not necessarily be used. As described above, there is a correlation between the projection condition of the shot processing device 10 and the mechanical strength. Therefore, in one embodiment, the measured projection condition can be calculated from the measured mechanical strength calculated by the strength analysis section 47 using the correlation between the projection condition of the shot processing device 10 and the mechanical strength. Further, it can be configured that the set projection condition is compared with the measured projection condition calculated from the measured mechanical strength, and when the difference between the two projection conditions exceeds a prescribed threshold, abnormality detection information is output. In this embodiment, the abnormality of the shot processing device 10 can be detected without using the AE sensor 16. Therefore, the number of components of the shot processing system 1 can be reduced.

[0074] Further, in the above-described embodiment, the shot peening device that imparts a compressive residual stress to the processing target is used as the shot processing device 10, but the shot processing device 10 is not limited to the shot peening device as long as it is a device that projects a shot medium. For example, the shot processing device 10 can be a shot blasting device that projects a shot medium to a processing target in order to deburr or adjust the surface roughness. Further, the shot processing device 10 related to the above-described embodiment is a shot peening device of an air nozzle type that projects a shot medium S by compressed air, but in one embodiment, the shot processing device 10 can be a shot peening device of a wheel type that projects a shot medium S by centrifugal force of a high-speed rotating impeller. In this case, the wheel rotation speed is included in the projection condition.

[0075] In the above-described embodiment, the measuring device 20 measures an elastic wave when the shot medium collides with the projection surface 20a using an AE sensor, but the measuring device 20 can measure a wave other than the elastic wave and output a signal waveform related to the wave. As a sensor that measures a wave other than the elastic wave, for example, a vibration sensor that measures vibration, an acceleration sensor, an impact sensor, an ultrasonic sensor that measures ultrasonic waves, an electromagnetic sensor that measures electromagnetic waves, an eddy current sensor that measures displacement, a laser displacement meter, an ultrasonic sensor, a color sensor that measures color, a Barkhausen noise sensor that measures Barkhausen noise, and the like can be cited.

[0076] Further, the above-described various embodiments can be combined within a range that does not contradict.

Claims

1. A shot peening system for performing shot peening by projecting a shot peening medium onto a workpiece, characterized in that, The shot peening system includes: A shot peening device is used to perform the shot peening process. The measuring device receives the shot peening medium projected from the shot peening treatment device and outputs a signal waveform related to the fluctuations generated by the collision of the shot peening medium. as well as A control device controls the shot peening apparatus and includes a processing condition acquisition unit, a control unit, an intensity analysis unit, and a correction unit. The processing condition acquisition unit acquires a required mechanical strength representing the intensity of the shot peening treatment performed on the object to be treated. The control unit controls the shot peening apparatus to perform the shot peening treatment on the measuring device under a first projection condition. The intensity analysis unit analyzes the signal waveform output from the measuring device through the shot peening treatment on the measuring device, thereby acquiring a measured mechanical strength representing the intensity of the shot peening treatment on the measuring device. The correction unit corrects the projection condition of the shot peening apparatus from the first projection condition to a second projection condition to reduce the difference between the required mechanical strength and the measured mechanical strength.

2. The shot peening system according to claim 1, characterized in that, The control device further includes a decision unit that determines the first projection condition based on the required mechanical strength.

3. The shot peening system according to claim 1 or 2, characterized in that, The measuring device includes: a projection surface for receiving the shot peening medium; and an AE sensor for outputting a signal waveform related to the elastic wave generated by the collision of the shot peening medium with the projection surface.

4. The shot peening system according to claim 1 or 2, characterized in that, The shot peening apparatus includes a second AE sensor fixed to the nozzle of the shot peening apparatus. This second AE sensor measures the elastic wave generated when the shot peening medium is projected and outputs a signal waveform related to the measured elastic wave. The control device also includes a projection condition analysis unit that analyzes the signal waveform output from the second AE sensor, thereby determining the projection conditions of the shot peening device.

5. The shot peening system according to claim 4, characterized in that, The control device also has an alarm output unit that outputs an alarm when the difference between the projection conditions set by the control unit for the shot peening device and the projection conditions measured by the projection condition analysis unit exceeds a predetermined threshold.

6. The shot peening system according to claim 5, characterized in that, The control device also has a second correction unit, which corrects the set projection conditions when the difference between the set projection conditions and the measured projection conditions exceeds a predetermined threshold.

7. A shot peening method, which is a shot peening method using a shot peening system, wherein the shot peening system includes a shot peening device for performing shot peening of a projected shot peening medium, characterized in that, The shot peening method includes: A process for obtaining the required mechanical strength representing the strength required for the shot peening treatment performed on the object to be treated; The process of performing the shot peening treatment on the measuring device under the first projection conditions from the shot peening treatment device; The process of obtaining a signal waveform related to the fluctuation generated by the collision between the shot peening medium and the measuring device; The process of obtaining a measured mechanical strength representing the intensity of the shot peening treatment performed on the measuring device by analyzing the signal waveform; and The process of modifying the projection conditions of the shot peening device from the first projection conditions to the second projection conditions to reduce the difference between the required mechanical strength and the measured mechanical strength.

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