Method for suppressing defects in press-molded products

Abstract

To restrict a defect in a press-formed product caused by a local defect of a metal plate member while restricting decrease in productivity resulting from inspection of the metal plate member.SOLUTION: There is provided a defect restriction method for a press-formed product including a cut-out step of cutting out a metal plate member to be processed into the press-formed product by press-working, from a long metal plate conveyed in a conveyance direction. The defect restriction method includes, prior to the cut-out step, a step of measuring at least either one of a thickness and a component of a predetermined inspection point in a cut-out range in which the metal plate member is to be cut in the cut-out step, and determining whether a measurement result is abnormal. The inspection point is determined as a point corresponding to an elongation point in which a degree of elongation of the metal plate member resulting from press working is equal to or greater than a predetermined degree. When the measurement result is abnormal, a step of changing a position of the cut-out range is executed prior to the cut-out step so that the inspection point determined to be abnormal in the measurement result and the elongation point are deviated from each other.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a method for suppressing defects in press-formed products. [Background technology]

[0002] When a metal plate having defects is press-formed, cracks may occur in the resulting press-formed product. Patent Document 1 discloses a technique for detecting defects in a metal plate, which is a technique for detecting defects in a steel plate based on the surface temperature distribution of the steel plate acquired by an infrared camera. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5494566 Summary of the Invention [Problem to be solved by the invention]

[0004] However, while the method of detecting defects using an infrared camera as in Patent Document 1 can inspect a wide area of ​​a metal plate, local defects, for example, of a few millimeters in size, may be overlooked because they are not reflected in the temperature distribution. Furthermore, if the entire area of ​​the metal plate is precisely inspected to prevent such local defects from being overlooked, the productivity of press-formed products decreases. Therefore, a technology has been desired that can prevent defects in press-formed products caused by local defects in the metal plate while preventing a decrease in productivity due to inspection. [Means for solving the problem]

[0005] The present disclosure can be realized in the following forms. According to one aspect of the present disclosure, there is provided a method for suppressing defects in press-formed products, the method including: a cutting-out step of cutting out a metal plate material to be processed into a press-formed product by press working from an elongated metal plate conveyed in a conveying direction along the conveying direction, the metal plate material being conveyed in the conveying direction; an inspection step of measuring at least one of a thickness and a composition of a predetermined inspection point in a cut-out range into which the metal plate material is to be cut in the cut-out step, the cut-out range having the same length in the conveying direction as the metal plate material, and determining whether the measurement result of the inspection point is abnormal; the inspection point is determined to be a point corresponding to an elongation point where the degree of elongation of the metal plate material due to the press working is equal to or greater than a predetermined degree; and a change step of changing a position of the cut-out range by conveying the metal plate in the conveying direction if the measurement result is abnormal, the method including: a change step of changing a position of the cut-out range by conveying the metal plate in the conveying direction so that the elongation point is offset from the inspection point where the measurement result is determined to be abnormal.

[0006] (1) According to one aspect of the present disclosure, there is provided a method for suppressing defects in press-formed products, the method including a cutting-out process for cutting out a metal plate material that is conveyed in a conveying direction and that is to be processed into a press-formed product by press working from a long metal plate along the conveying direction. This method for suppressing defects in press-formed products includes, prior to the cutting-out process, an inspection process for measuring at least one of the thickness and composition of a predetermined inspection point in a cutting-out range from which the metal plate material is to be cut out in the cutting-out process, and determining whether the measurement result of the inspection point is abnormal. The inspection point is determined to be a point corresponding to a point where the degree of elongation of the metal plate material due to the press working is equal to or greater than a predetermined level. If the measurement result is abnormal, a change process for changing the position of the cutting-out range is performed prior to the cutting-out process so that the inspection point where the measurement result is determined to be abnormal is offset from the elongated point. In this configuration, by measuring predetermined inspection locations and determining whether the measurement results are abnormal, it is possible to prevent locations in the metal plate that have a large degree of elongation during press working from overlapping with locations that have abnormal thickness or composition, thereby preventing a decrease in productivity due to inspection of the metal plate and preventing cracks in the press-formed product caused by local defects in the metal plate. (2) In the above embodiment, in the changing step, the position of the cut-out range may be moved upstream in the conveying direction by a distance shorter than the length of the cut-out range in the conveying direction. This embodiment increases the possibility of cutting out more metal plate material from the metal plate compared to an embodiment in which the position of the cut-out range is moved upstream by a distance equal to or greater than the length of the cut-out range in the conveying direction. (3) In the above embodiment, in the changing step, the position of the cut-out range may be changed so that the inspection location where the measurement result is determined to be abnormal is included in a range of the metal plate material that is removed in a step subsequent to the cutting step. In this embodiment, the location of the metal plate material where the measurement result is abnormal is removed in a subsequent step, thereby further improving the quality of the press-formed product. (4) In the above embodiment, after the change step is performed, an additional inspection step may be performed prior to the cut-out step to determine whether the measurement result of the new inspection point in the cut-out range whose position has been changed is abnormal, and if the measurement result in the additional inspection step is abnormal, the position of the cut-out range whose position has been changed may be further changed by performing an additional change step prior to the cut-out step. With this embodiment, it is possible to further reduce the possibility of cracks occurring in the press-formed product due to local defects in the metal plate material.

[0007] The present disclosure can be realized in various forms, such as a cutting device, in addition to the above-described form as a method for suppressing defects in press-molded products. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is an explanatory diagram showing how a press-formed product is manufactured in the first embodiment. [Figure 2] FIG. 3 is a process diagram illustrating a preparation process in the first embodiment. [Figure 3] FIG. 10 is a process diagram illustrating a preparation process in the second embodiment. [Figure 4] FIG. 10 is a process diagram illustrating a preparation process in the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] A. First embodiment: Fig. 1 is an explanatory diagram showing how a press-formed product PR is manufactured in this embodiment. The press-formed product PR shown in the lower part of Fig. 1 is manufactured through a preparation process of preparing a metal plate material MPp using a cutting device 100, as shown in the upper part of Fig. 1, and a press process of press-forming the metal plate material MPp with a press machine 200, as shown in the middle part of Fig. 1.

[0010] In the preparation step, the metal plate material MPp is cut out from a long metal plate MP by a cutting device 100. The material of the metal plate MP may be any material. For example, the metal plate MP may be a steel plate, an aluminum plate, or a zinc plate.

[0011] The cutting device 100 includes an inspection unit 110, a cutting unit 120, a rolling unit 130, and a control unit 150.

[0012] The metal sheet MP is wound in a roll shape around the roll unit 130. The metal sheet MP wound in a roll shape is also called a metal sheet roll MR. The roll unit 130 unwinds the metal sheet MP by rotating the metal sheet roll MR under the control of the control unit 150. The metal sheet MP unwound by the roll unit 130 is transported in a transport direction d1 along the longitudinal direction of the metal sheet MP. The cutting device 100 may be provided with a conveyor, rollers, guides, etc. as a transport unit for transporting the metal sheet MP.

[0013] The cutting unit 120 is configured as a cutting machine that cuts the metal sheet MP. In this embodiment, the cutting unit 120 cuts the metal sheet MP by sandwiching it between a pair of cutting blades 121 from above and below. The cutting blades 121 are arranged along a direction intersecting the conveyance direction d1, more specifically, perpendicular to the conveyance direction d1. In this specification, perpendicular includes a range of 90°±10°. In other embodiments, the cutting unit 120 may be configured as, for example, a laser cutting machine or a water jet cutting machine.

[0014] The inspection unit 110 is used in an inspection process described later. In this embodiment, the inspection unit 110 has a thickness measuring device 111 and a component analyzer 115. In this embodiment, the thickness measuring device 111 and the component analyzer 115 are pre-placed at positions that overlap with an inspection point Dt in a measurement process described later when viewed in the vertical direction.

[0015] The thickness measuring device 111 is configured as an ultrasonic thickness gauge and has a probe that transmits and receives ultrasonic waves. The thickness measuring device 111 measures the thickness of the metal plate MP based on the time it takes for ultrasonic waves transmitted from the probe while the probe is in contact with one side of the metal plate MP to be reflected by the other side of the metal plate MP and received by the probe. In this embodiment, the thickness measuring device 111 is disposed above the metal plate MP. In other embodiments, the thickness measuring device 111 may be configured as a non-destructive thickness gauge other than an ultrasonic thickness gauge, for example, as a thickness measuring device that measures the thickness by sandwiching the inspection point Dt between two contact sensors from above and below.

[0016] The component analyzer 115 is configured as an energy dispersive X-ray fluorescence analyzer. The component analyzer 115 has an irradiation unit that irradiates X-rays toward the metal plate MP, a semiconductor detector that detects fluorescent X-rays emitted from the area irradiated with X-rays, and an analyzer that analyzes the detected fluorescent X-rays to identify elements. The component analyzer 115 is disposed below the metal plate MP. In other embodiments, the component analyzer 115 may be configured as, for example, a non-destructive component analyzer other than an X-ray fluorescence analyzer, or may be configured as an analyzer that performs component analysis by laser-induced breakdown spectroscopy, for example.

[0017] In this embodiment, the thickness measuring device 111 is configured to be movable in the vertical direction by a first moving mechanism 112. The component analyzer 115 is configured to be movable in the vertical direction by a second moving mechanism 116. The first moving mechanism 112 and the second moving mechanism 116 are configured by, for example, a linear actuator or a robot, and are controlled by the control unit 150.

[0018] The control unit 150 is configured as a computer having a CPU and a storage unit. In this embodiment, press data 151, which will be described later, is stored in the storage unit of the control unit 150. The press data 151 is data that represents the deformation of the metal plate material MPp into the press-formed product PR during press working. The press data 151 may be, for example, data based on simulation results or data based on experimental results.

[0019] Fig. 2 is a process diagram illustrating the preparation process in this embodiment. As will be described later, the preparation process represents a method for suppressing defects in a press-formed product PR. The preparation process can also be said to represent a method for manufacturing a metal plate material MPp and a method for cutting a metal plate MP. As shown in Fig. 2, the preparation process includes an inspection process and a cutting process.

[0020] The inspection process refers to a process of measuring an inspection point Dt in a cutout range Rc of the metal plate MP prior to the cutting process and determining whether the measurement result of the inspection point Dt is abnormal. The cutting process refers to a process of cutting a metal plate material MPp from the metal plate MP by cutting the metal plate MP conveyed in the conveying direction d1. The cutout range Rc refers to the range of the metal plate MP from which the metal plate material MPp is to be cut in the cutting process after the inspection process. In this embodiment, the cutout range Rc corresponds to the range from the leading edge position P1 of the metal plate MP in the conveying direction d1 to the planned cutting position P2. The planned cutting position P2 refers to the position in the conveying direction d1 where the metal plate MP is to be cut in the next cutting process. That is, in this embodiment, the length L1 of the cutout range Rc in the conveying direction d1 is equal to the distance between the leading edge position P1 and the planned cutting position P2. In FIGS. 1 and 2, the cutout range Rc is indicated by halftone hatching.

[0021] "Measuring the inspection point Dt" refers, more specifically, to measuring at least one of the thickness and composition of the inspection point Dt. The inspection point Dt is predetermined as a point corresponding to an elongated point of the metal plate material MPp. The elongated point refers to a point where the degree of elongation of the metal plate material MPp due to press processing is equal to or greater than a predetermined level. If the elongated point overlaps with a locally thin area of ​​the metal plate material MPp, a locally contaminated area, or a precipitated area of ​​impurity components, cracks may occur in the press-formed product PR formed using the metal plate material MPp. The elongation criteria for determining the elongated point and the inspection point Dt are preferably determined so that, for example, a portion of the metal plate material MPp that is likely to cause cracks in the press-formed product PR can be inspected if there is a defect in that area.

[0022] In this embodiment, the inspection process includes a measurement process in step S110 and a determination process in step S120. In this embodiment, the inspection process is performed while the transport of the metal plate MP is temporarily stopped. In step S110, the control unit 150 measures both the thickness and the components of the inspection point Dt. More specifically, in step S110, the control unit 150 controls the first movement mechanism 112 to bring the probe of the thickness measuring device 111 into contact with the upper surface of the inspection point Dt from vertically above, and measures the thickness of the inspection point Dt using the thickness measuring device 111. In addition, the control unit 150 controls the second movement mechanism 116 to bring the irradiation unit of the component analyzer 115 into contact with the lower surface of the metal plate MP from vertically below, and measures the components of the inspection point Dt using the component analyzer 115.

[0023] In step S120, the control unit 150 determines whether the measurement result in step S110 is abnormal. More specifically, in step S120, the control unit 150 determines that the measurement result is abnormal if at least one of the thickness measurement value and the component measurement value measured in step S110 is abnormal. In this embodiment, the control unit 150 determines that the thickness measurement value measured in step S110 is abnormal if the thickness measurement value is outside a predetermined reference thickness range of ±20%. Furthermore, in this embodiment, the control unit 150 determines that the component measurement value is abnormal if the content of a predetermined type of impurity component at the inspection point Dt is outside a predetermined reference content range based on the component measurement value measured in step S110. For example, if the metal plate MP is a steel plate, silicon, zinc, copper, and other components are used as impurity components contained in the inspection point Dt to determine whether the component measurement value is abnormal.

[0024] If the measurement result is determined to be abnormal in step S120, the control unit 150 executes a change process in step S130. The change process refers to a process of changing the position of the cut-out range Rc prior to the cut-out process in step S140 so that the test point Dt, where the measurement result is determined to be abnormal, is offset from the extension point. In this embodiment, in step S130, the control unit 150 moves the position of the cut-out range Rc upstream in the conveying direction d1 by a distance L2, which is shorter than the length L1. Hereinafter, the cut-out range whose position has been changed will also be referred to as the changed cut-out range Rc2. In FIG. 2, the changed cut-out range Rc2 is indicated by halftone hatching.

[0025] More specifically, in step S130, the control unit 150 controls the roll unit 130 and the conveying unit to unwind the metal sheet MP from the roll unit 130 by length L2 and convey the metal sheet MP downstream in the conveying direction d1 by length L2. As a result, in the changed cut-out range Rc2, a point P4 corresponding to the elongated portion in the changed cut-out range Rc2 and a point P3 determined to be abnormal in the measurement result in step S120 are positioned so as to be offset from each other. Then, the control unit 150 cuts the metal sheet MP in this state using the cutting unit 120, thereby cutting and removing scrap material EM having length L2 from the metal sheet MP.

[0026] In step S140, the control unit 150 executes the cutting process. If the measurement result is determined to be normal in step S120, the control unit 150 cuts out a metal plate material MPp from the unchanged cutting range Rc in step S140. On the other hand, if the measurement result is determined to be abnormal in step S120, the control unit 150 cuts out a metal plate material MPp from the changed cutting range Rc2 in step S140. More specifically, in step S140, the control unit 150 controls the roll unit 130 and the conveying unit to unwind the metal plate MP from the roll unit 130 by a length L1 and move the metal plate MP downstream in the conveying direction d1 by the length L1. Then, the control unit 150 cuts the metal plate MP using the cutting unit 120 in this state. As a result, a metal plate material MPp having a length L1 is cut out from the metal plate MP. It should be noted that when the metal plate MP is cut by the cutting unit 120 in step S130 or step S140, the conveyance of the metal plate MP may be temporarily stopped.

[0027] The control unit 150, for example, repeatedly executes the above-described preparation process multiple times to cut out multiple metal plate materials MPp from the metal plate MP. The preparation process may be executed, for example, until a predetermined number of metal plate materials MPp are cut out, or until the metal plate MP is exhausted. The cut-out metal plate materials MPp are transported to the press machine 200 by, for example, a conveyor or a robot, and processed into a press-formed product PR by the press machine 200.

[0028] According to the preparation process of the present embodiment described above, an inspection process is provided in which, prior to the cutting-out process, at least one of the thickness and composition of the inspection point Dt in the cutting-out range Rc of the metal plate MP is measured and the measurement result of the inspection point Dt is determined to be abnormal. The inspection point Dt is predetermined as a point corresponding to a point where the degree of elongation of the metal plate MPp due to press working is equal to or greater than a predetermined level. If the measurement result of the inspection point Dt is abnormal, a modification process is performed prior to the cutting-out process in which the position of the cutting-out range Rc is changed so that the inspection point Dt whose measurement result is determined to be abnormal is offset from the elongated point. This prevents the metal plate MPp from overlapping a point with an abnormal thickness or composition by measuring the predetermined inspection point Dt and determining whether the measurement result is abnormal. Therefore, it is possible to suppress a decrease in productivity due to inspection of the metal plate MPp while suppressing cracks in the press-formed product PR caused by local defects in the metal plate MPp. In this way, according to the preparation process in this embodiment, a method for suppressing defects in the press-formed product PR is realized.

[0029] In the present embodiment, in the changing step, the position of the cut-out range Rc is moved upstream in the conveying direction d1 by a distance L2 that is shorter than the length L1 of the cut-out range Rc. This increases the possibility that more metal plate materials MPp can be cut out from the metal plate MP, compared to when the distance L2 is equal to or greater than the length L1.

[0030] B. Second embodiment: 3 is a process diagram illustrating the preparation process in the second embodiment. In the change process of step S130b shown in FIG. 3, unlike step S130 in the first embodiment described in FIG. 2, the position of the cut-out range Rc is changed so that the inspection point Dt is included in the removal range of the metal plate material MPp. The removal range refers to the range of the metal plate material MPp that is removed in a process subsequent to the cut-out process. Parts of the preparation process and the configuration of the cutting device 100 in the second embodiment that are not specifically described are the same as those in the first embodiment.

[0031] The subsequent process may be, for example, a pressing process, or a process performed before or after the pressing process in which a removal area is punched out with a punch or a process performed after the pressing process in which a removal area is cut out with a cutter. The removal area is determined based on, for example, simulation results of deformation of the workpiece in the subsequent process or experimental results of deformation of the workpiece in the subsequent process. For example, if the subsequent process is a pressing process, the removal area may be determined based on press data 151.

[0032] In this embodiment, the metal plate material MPp has a removal range Rv1 and a removal range Rv2. In this embodiment, the control unit 150 changes the position of the cut-out range in step S130b so that the inspection location where the measurement result was determined to be abnormal in step S120 is included in the removal range Rv1. More specifically, the control unit 150 changes the position of the cut-out range so that the location P3 where the measurement result was determined to be abnormal in step S120 is included in the range R1 of the changed cut-out range Rc2. The range R1 corresponds to the removal range Rv1 and is located upstream in the conveying direction d1 of the range R2 corresponding to the removal range Rv2. Note that in step S130b of this embodiment, the position of the cut-out range is moved upstream in the conveying direction d1 by a distance shorter than the length L1, as in the first embodiment.

[0033] According to the preparation process of the second embodiment described above, in the change process, the position of the cut-out range is changed so that the inspection location where the measurement result is determined to be abnormal is included in the removal range of the metal plate material MPp. Therefore, the location P3 of the metal plate material MPp where the measurement result is abnormal can be removed in a subsequent process, thereby further improving the quality of the press-formed product PR. Furthermore, in this embodiment, the position of the cut-out range is changed in the change process so that the location P3 is included in the range R1 upstream of the range R2. This increases the possibility of cutting out more metal plate material MPp from the metal plate MP compared to when the position of the cut-out range is changed so that the location P3 is included in the range R2.

[0034] C. Third embodiment: FIG. 4 is a process diagram illustrating the preparation process in the third embodiment. Unlike the first embodiment, the preparation process in this embodiment involves a new inspection process after the modification process is performed and before the cutting process is performed. Hereinafter, this new inspection process performed after the modification process will also be referred to as an additional inspection process. Parts of the preparation process and the configuration of the cutting device 100 in the second embodiment that are not specifically described are the same as those in the first embodiment.

[0035] The additional inspection process includes an additional measurement process in step S132 and an additional determination process in step S134. Step S132 is similar to step S110 except that a new inspection location Dt in the post-change cutout range Rc2 is measured. The new inspection location Dt is the same location as location P4. In step S134, the control unit 150 determines whether the measurement result of the new inspection location Dt measured in step S132 is abnormal, as in step S120. If the measurement result is determined to be abnormal in step S134, the control unit 150 executes a new modification process in step S136. That is, in step S136, the control unit 150 further modifies the position of the post-change cutout range Rc2. A modification process newly executed after the additional inspection process, such as step S136, is also referred to as an additional modification process. Note that in the modification process or additional modification process in the third embodiment, the position of the cutout range may be modified so that location P3 is included in the removal range, as in the second embodiment. In other embodiments, for example, the additional inspection step and the additional modification step may each be performed two or more times.

[0036] If the measurement result is determined to be normal in step S134, the control unit 150 cuts out the metal plate material MPp from the changed cut-out range Rc2 in step S140. On the other hand, if the measurement result is determined to be abnormal in step S134, the control unit 150 cuts out the metal plate material MPp from the cut-out range whose position has been further changed in step S136 in step S140.

[0037] According to the preparation process in the third embodiment described above, after the modification process is performed, the additional inspection process is performed before the cutting-out process, and if the measurement result in the additional inspection process is abnormal, the additional modification process is performed before the cutting-out process. This further reduces the possibility that a crack will occur in the press-formed product PR due to a local defect in the metal plate material MPp.

[0038] D. Other Embodiments: (D1) In the above embodiment, in the changing step, the position of the cut-out range Rc is moved upstream in the conveying direction d1 by a distance L2 that is shorter than the length L1. However, the position of the cut-out range Rc does not have to be moved in this manner. For example, the position of the cut-out range Rc may be moved upstream in the conveying direction d1 by a distance equal to or greater than the length L1.

[0039] (D2) In the above embodiment, both the thickness and the composition of the inspection point Dt are measured in the inspection process, but it is also possible to measure either the thickness or the composition.

[0040] (D3) In the above embodiment, one inspection point Dt is defined within one cut-out range Rc. However, multiple inspection points Dt may be defined within one cut-out range Rc. In this case, the thickness measuring devices 111 and the component analyzers 115 may be provided in numbers corresponding to the number of inspection points Dt. Furthermore, for example, the thickness measuring devices 111 and the component analyzers 115 may be configured to be movable in the vertical and horizontal directions, and during the inspection process, the thickness measuring devices 111 and the component analyzers 115 may be moved appropriately to positions where each inspection point Dt can be measured.

[0041] (D4) In the above embodiment, the inspection process is performed while the transport of the metal plate MP is temporarily stopped. However, the inspection process may be performed while the metal plate MP is being transported. For example, the transport of the metal plate MP may be continued without stopping the transport of the metal plate MP while the preparation process is being performed.

[0042] The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit thereof. For example, the technical features in the embodiments corresponding to the technical features in each aspect described in the Summary of the Invention section can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted. [Explanation of symbols]

[0043] 100...Cutting device, 110...Inspection unit, 111...Measuring instrument, 112...First moving mechanism, 115...Component analyzer, 116...Second moving mechanism, 120...Cutting unit, 121...Cutting blade, 130...Roll unit, 150...Control unit, 151...Press data, 200...Press machine

Claims

1. A method for suppressing defects in a press-formed product, comprising: a cutting step of cutting out a metal plate material to be processed into a press-formed product by press working from a long metal plate conveyed in a conveying direction along the conveying direction, an inspection step, prior to the cutting step, of measuring at least one of the thickness and the components of a predetermined inspection point in a cut-out range into which the metal plate material is to be cut in the cutting step, the cut-out range having the same length as the metal plate material in the conveying direction, and determining whether or not the measurement result of the inspection point is abnormal; the inspection point is determined as a point corresponding to an elongation point where the degree of elongation of the metal plate material due to the press working is equal to or greater than a predetermined degree, If the measurement result is abnormal, prior to the cutting-out process, a change process is carried out to change the position of the cutting-out range by transporting the metal plate in the transport direction so that the inspection point where the measurement result was determined to be abnormal and the extension point are misaligned.This is a method for suppressing defects in press-molded products.

2. The method for suppressing defects in a press-formed product according to claim 1, In the changing step, the position of the cut-out range is moved upstream in the conveying direction by a distance shorter than the length of the cut-out range in the conveying direction.

3. The method for suppressing defects in a press-formed product according to claim 1, In the changing step, a position of the cut-out range is changed so that the inspection point at which the measurement result is determined to be abnormal is included in a removal range that is removed from the metal plate material in a step subsequent to the cutting-out step; The method for suppressing defects in a press-formed product, wherein the post-process is either a press process in which the metal plate material is processed by press working, or a punch process in which the removal area is punched out with a punch.

4. The method for suppressing defects in a press-formed product according to any one of claims 1 to 3, After the change step is performed, an additional inspection step is performed prior to the cut-out step, thereby determining whether or not the measurement result of the new inspection point in the cut-out range whose position has been changed is abnormal; A method for suppressing defects in press-molded products, in which, if the measurement results in the additional inspection process are abnormal, the position of the cut-out range whose position has been changed is further changed by performing an additional change process prior to the cut-out process.

Images