Progressive press working method and working system therefor

Abstract

To provide a progressive press working method including a maintenance step for a progressive press die, and a working system therefor.SOLUTION: The invention provides a progressive press working method performed by a press working apparatus and including a maintenance step for a progressive press die. A management device, which gives a notification to an operator that the maintenance step should be performed, comprises: a counting unit that, after the start of pressing, counts a number of shots for each processing stage; and a storage unit in which maintenance information is recorded, the maintenance information comprising, for each processing stage, a pair of a specified number of shots and maintenance details. When the specified number of shots is reached for any pair included in the maintenance information, the management device notifies the operator that the maintenance step should be performed, together with the processing stage corresponding to the pair and the maintenance details, and resets the corresponding shot count of the counting unit.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a progressive press working method and a working system using a press working device, and more particularly to a progressive press working method and a working system including a maintenance process for a progressive press die. [Background technology]

[0002] A progressive press working method using a press working device is known in which two or more press working steps are performed within one die, and a strip of workpiece material is automatically sent to the next step within the die while being pressed. This method is characterized by its extremely fast processing speed and excellent productivity compared to other press working methods, as it eliminates the need to manually load and unload the workpiece material from the die between each step.

[0003] In order to prevent defects in press processing, it has been necessary to find the optimum processing conditions for the press machine for the type of defect, such as burrs, warping, scratches, deviations from dimensional or angle tolerances, and then optimize the processing conditions for the press machine that cause the defect. In other words, the processing conditions, such as oil volume and production speed, are compiled into a database in advance and managed to improve quality.

[0004] On the other hand, because die wear and the like are also a major cause of defects, a press processing method has been proposed in which the number of presses required for maintenance is set for each die, and when the set number of presses is reached, a message is displayed to the worker indicating that the scheduled number of maintenance has been reached, urging the worker to perform maintenance such as die polishing. After the worker has performed the required maintenance work, the set number of presses is reset to zero and processing is resumed.

[0005] For example, Patent Document 1 discloses a method for managing dies used in press equipment such as turret punch presses, servo presses, etc. In this method, maintenance count data for each component of a die made up of multiple components that vary in the number of times they are used in one motion is stored, including data on the number of actual uses of the components, data on the number of planned uses, and a multiplier corresponding to the number of uses per motion, and the multiplier is added to the data on the number of actual uses of the components for each motion, and when the planned number of uses data is reached, a notification to that effect is sent to the worker, urging them to polish the die. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-160215 Summary of the Invention [Problem to be solved by the invention]

[0007] As described above, in progressive press working, different processes are performed at each stage, so when managing dies based on the number of presses, it is possible to consider prescribing an upper limit on the number of presses according to the stage where the processing conditions are predicted to be the most severe, and then carrying out maintenance. However, since the types of defects that can occur vary widely, such predictions have been difficult.

[0008] The present invention has been made in consideration of the above circumstances, and its object is to provide a progressive press processing method and processing system that includes a maintenance process for progressive press dies. [Means for solving the problem]

[0009] The inventors of the present application conducted extensive and detailed observations of the behavior of deterioration of dies at each stage of progressive press working, along with the operation of the press machine. As a result, they came to the realization that the deterioration of dies at each stage is linked to each other, leading to the occurrence of a specific defect, i.e., that the deterioration of dies at only one stage does not lead to the occurrence of a specific defect, and thus arrived at the present invention.

[0010] That is, the method according to the present invention is a progressive press processing method using a press processing device, which includes a maintenance process for a progressive press die having a plurality of processing stages each arranged at equal intervals in sequence along a discharge line for the workpiece, and the management device that notifies the worker that the maintenance process should be performed includes a counting unit that counts the number of shots for each of the processing stages after processing begins, and a memory unit in which maintenance information consisting of a set of a specified number of shots and maintenance content for each of the processing stages is recorded, and when the specified number of shots for any of the sets of maintenance information is reached, the management device notifies the worker that the maintenance process should be performed, along with the processing stage corresponding to the set and the maintenance content, and resets the corresponding number of shots in the counting unit.

[0011] According to this feature, by performing maintenance on one stage before the part of the mold corresponding to that stage has a significant impact on the deterioration of the part of the mold corresponding to another stage, product defects are prevented and high productivity is achieved.

[0012] In the above invention, the maintenance information may include sets of different specified shot counts and different maintenance details for the same processing stage. This feature further reduces the influence of mold deterioration between stages, prevents product defects, and provides high productivity.

[0013] In the above-described invention, the management device may be characterized in that, in response to the operation of a stopping device that stops the press working apparatus when a defective product is found in a processed product manufactured by the press working apparatus, the management device accepts external input of the processing stage that caused the defective part in the defective product and maintenance details corresponding to the defective part, and then, upon further receiving input that the maintenance details have been carried out, if the pair that matches the processing stage and the maintenance details based on the external input exists in the memory unit, the management device resets the corresponding number of shots in the counter, and if not, accepts further input of the number of shots based on the external input, creates a new pair, and registers it in the memory unit. This feature further suppresses the effects of mold deterioration between stages, prevents product defects, and achieves high productivity.

[0014] Furthermore, the system according to the present invention may be a progressive press processing system using a press processing apparatus including a maintenance process for progressive press dies having a plurality of processing stages arranged in sequence at equal intervals along a feed line for the workpiece, wherein the management device that notifies an operator that the maintenance process should be performed includes a counting unit that counts the number of shots for each of the processing stages after processing starts, and a memory unit that stores maintenance information for each of the processing stages, the maintenance information consisting of a set of a specified number of shots and maintenance details, and when the number of shots for any of the sets in the maintenance information is reached, the management device notifies the operator that the maintenance process should be performed, along with the processing stage corresponding to the set and the maintenance details, and resets the corresponding number of shots in the counting unit. This feature further suppresses the effects of deterioration of the dies between stages, prevents product defects, and achieves high productivity.

[0015] According to this feature, by performing maintenance on the mold for one stage before the part of the mold corresponding to one stage has a significant impact on the deterioration of the part of the mold corresponding to another stage, product defects can be prevented and high productivity can be achieved.

[0016] In the above invention, the maintenance information may include sets of different specified shot counts and different maintenance details for the same processing stage. This feature further reduces the influence of mold deterioration between stages, prevents product defects, and provides high productivity.

[0017] In the above-described invention, the management device may be characterized in that, in response to the operation of a stopping device that stops the press working apparatus when a defective product is found in a processed product manufactured by the press working apparatus, the management device accepts external input of the processing stage that caused the defective part in the defective product and maintenance details corresponding to the defective part, and then, upon further receiving input that the maintenance details have been carried out, if the pair that matches the processing stage and the maintenance details based on the external input exists in the memory unit, the management device resets the corresponding number of shots in the counter, and if not, accepts further input of the number of shots based on the external input, creates a new pair, and registers it in the memory unit. This feature further suppresses the effects of mold deterioration between stages, prevents product defects, and achieves high productivity. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 10 is a diagram illustrating a layout by progressive press working. [Figure 2] 10 is a graph showing the relationship between the processing speed for each processing stage in progressive press processing and the number of shots that can maintain quality. [Figure 3] 1 is a block diagram of a progressive press working system according to one embodiment of the present invention and a press working device connected thereto. DETAILED DESCRIPTION OF THE INVENTION

[0019] First, the background to the invention will be described.

[0020] FIG. 1 shows a layout of the steps for processing a workpiece material M into a predetermined part using progressive press working. As shown in this layout, in progressive press working, the workpiece material M, which is a strip-shaped metal plate, is fed along a feed line, and is processed in sequence through multiple processing stages along the feed line using progressive press dies arranged at equal intervals. As shown in the figure, different processing stages within the die perform different processing operations, such as punching, bending, and cutting. Therefore, the deterioration behavior of the corresponding parts of the die (die components) varies depending on each processing stage, and even within a single processing stage, depending on the processing location, and the frequency of maintenance required varies depending on the processing stage or processing location.

[0021] Generally, when a defect is discovered during an inspection of a product obtained from processed material M, one possible solution is to perform maintenance on the part of the mold that corresponds to the processing stage that caused the defect. However, in the case of mass-produced products, even if processing is stopped after a defect is discovered, a large number of defective products may still be produced. Also, when mass-produced products cannot be inspected 100%, even if no defects are found in the sample selected for inspection, defects may have occurred before and after, making it difficult to achieve high productivity. Therefore, preventative maintenance before defects occur is considered, but to do so, it is necessary to investigate the deterioration behavior of the mold.

[0022] Therefore, as shown in Figure 2, the inventors investigated the limit value of the number of shots that can maintain a predetermined quality standard, thereby observing the deterioration behavior of dies at each processing stage of progressive press working. Note that the investigation was conducted for a progressive press working process with four processing stages. Specifically, for each of Product A and Product B, the processing speed (number of shots per minute) was changed to 100, 200, and 300 SPM, and the limit value of the number of shots was investigated for each processing stage. The limit values ​​of the number of shots were displayed for both high and medium quality standards. In other words, the limit value of the number of shots was smaller for high-level quality standards. As a result, it was found that, overall, the limit value of the number of shots tends to decrease as the processing speed increases, but the rate of decrease varies. For example, if we look at processing stages (mold stages) No. 2 and No. 3 for product A, when changing from SPM 100 to SPM 200, the limit value for the number of shots at processing stage No. 2 drops sharply, but the rate of decrease is small at processing stage No. 3, and when changing from SPM 200 to SPM 300, the rate of decrease is small at processing stage No. 2, but large at processing stage No. 3. In this way, even for a single mold, trends differ depending on the processing stage, and it was found that mold maintenance management needs to be carried out on a processing stage-by-process basis.

[0023] On the other hand, when we look at machining stage No. 1, there is almost no change in the limit value of the number of shots due to the machining speed. Only a slight decrease is observed for product B, which has a medium quality standard of SPM300. This is thought to be because machining stage No. 1 processes blank material with no previous process, and can always process material of consistent quality. In other words, it is thought that there is a correlation between the deterioration of the mold between machining stages, such that deterioration of the part of the mold corresponding to one machining stage affects the deterioration of other parts.

[0024] Therefore, even if maintenance is performed on a corresponding part of a mold immediately before a defect occurs that causes the product to deviate from the specified quality standards, it is likely that other parts have already been affected by the defect and are deteriorating in some way. In this case, it is difficult to predict the occurrence of defects in those other parts, and defects that deviate from the quality standards may occur immediately, requiring further maintenance. In other words, even if the product does not deviate from the quality standards, deterioration of the mold may affect other parts, accelerating their deterioration. Therefore, the inventors of the present application came up with the idea of ​​performing maintenance before the deterioration of different parts of the mold affects each other and causes a correlation.

[0025] Next, a progressive press working method and a progressive press working system including a maintenance process for a progressive press die according to one embodiment of the present invention will be described with reference to FIG.

[0026] As shown in Figure 3, the progressive press working system 2 can be configured by a computer connected to a press working device 1 using a progressive press die 12. The press working device 1 includes a working unit 11 that performs press working using the progressive press die 12, a control device 14 that controls the operation of the working unit 11, and a stopping device 15 that stops the operation of the working unit 11 based on an external signal. The progressive press die 12 has multiple working stages 13 (here, No. 1 to No. 4) that are arranged in order at equal intervals along the feed line of the workpiece material.

[0027] On the other hand, the progressive press working system 2 includes a management device 20 that notifies an operator that a maintenance process for the progressive press die 12 should be performed, and an input device 29.

[0028] The management device 20 is connected to the control device 14 and the stop device 15 of the press working apparatus 1, and includes a counter 21, a memory 22, and a display 23. The counters 21 are provided individually for each processing stage 13 and count the number of shots for that processing stage 13. The number of shots is a value that is incremented by one each time the progressive press die 12 is pressed. For example, the control device 14 sends one signal per shot based on a sensor that detects the operation of the crankshaft that presses the progressive press die of the press working apparatus 1. The management device 20 receives this signal and increments all of the shot counts in the counter 21 by one. Because the progressive press die is used, the cumulative number of shots for each processing stage 13 is the same. However, as described below, each time a maintenance process is performed, the shot counter corresponding to the processing stage 13 on which the maintenance process was performed is reset, and the number of shots for each processing stage 13 after the maintenance process is counted. That is, the maintenance process is carried out individually for the plurality of processing stages 13, and the counting unit 21 counts the number of shots thereafter for each processing stage 13 individually.

[0029] The storage unit 22 stores maintenance information corresponding to each of the processing stages 13. The maintenance information includes a set of a specified number of shots and a maintenance content. In other words, the maintenance content to be performed when the counted number of shots reaches the specified number of shots in the corresponding processing stage 13 is recorded. It is also preferable that the maintenance information further includes a processing content, which is information regarding processing to be performed on the corresponding part.

[0030] The display unit 23 displays information that should be notified to the operator. For example, the display unit 23 may display the specified number of shots in the maintenance information in contrast to the current number of shots. Furthermore, when the number of shots reaches the specified number of shots, the display unit 23 displays the number of the corresponding processing stage 13 and the maintenance content to notify the operator that a maintenance process for the progressive press die 12 should be performed.

[0031] The input device 29 is connected to the management device 20 so that the management device 20 can receive external input when operated by an operator. The management device 20 performs a necessary operation based on the external input from the input device 29. The input device 29 may be provided integrally with the display unit 23.

[0032] The management device 20 is further connected to a stopping device 15 of the press working device 1. The stopping device 15 stops the press working device 1 when a defective product is found in a processed product manufactured by the press working device 1. This stopping operation may be performed based on an external input from the input device 29 if the defect is found by an operator, or may be performed based on a signal from a sensor or the like that mechanically detects defective parts.

[0033] Next, the operation of the progressive press working system 2 will be described.

[0034] First, the storage unit 22 of the management device 20 stores, as maintenance information, a set of the specified number of shots and maintenance content corresponding to each of the processing stages 13 No. 1 to No. 4. As described above, the maintenance information may further include processing content. Here, the specified number of shots is the number of shots that can be continuously performed on the progressive press processing without performing maintenance on the corresponding processing stage 13. The specified number of shots is a predetermined value that is input, for example, externally by an operator and stored. The maintenance information may be determined based on past performance, but the specified number of shots in particular may be updated as the product is repeatedly manufactured, as described below. Furthermore, maintenance content includes, for example, clearance adjustment, bending angle adjustment, die cutting edge grinding, punch cutting edge grinding, etc. Furthermore, processing content includes, for example, small hole punching, drawing, cutting and bending, etc.

[0035] Then, progressive press working is performed by the press working device 1. Then, the management device 20 causes the counting unit 21 to count the number of shots. In detail, the counting unit 21 receives a signal for each shot from the control device 14 of the press working device 1, and adds 1 to all of the counters for the number of shots corresponding to each of the processing stages 13 No. 1 to No. 4.

[0036] Meanwhile, the management device 20 monitors the shot count counted by the counting unit 21 and compares it with the specified shot count in the corresponding maintenance information stored in the memory unit 22. When the shot count corresponding to any of the processing stages 13 Nos. 1 to 4 reaches the specified shot count, the management device 20 notifies the worker by displaying on the display unit 23 that a maintenance process should be performed. At this time, the display unit 23 displays maintenance information including the specified number of shots that has been reached, and the number of the processing stage 13 corresponding to the maintenance information. At this time, for example, the management device 20 can send a signal to the stop device 15 to stop the progressive press working of the press working device 1.

[0037] Meanwhile, the worker performs the maintenance process for the progressive press die 12 in accordance with the information notified by the management device 20 on the display unit 23, and inputs information that the maintenance has been completed through the input device 29. In response to this input, the management device 20 resets to zero the counter for the number of shots in the counting unit 21, which corresponds to the processing stage for which the specified number of shots has been reached and maintenance has been completed.

[0038] Upon receiving the input indicating that maintenance has been completed, the management device 20 allows the operation of the processing unit 11 of the press processing device 1. Then, as the press processing device 1 resumes progressive press processing, it again starts counting the number of shots for each processing stage individually. At this time, the reset counter starts counting from zero, and the other counters continue counting from the values ​​before maintenance.

[0039] This manufacturing method allows preventative maintenance of mold deterioration. That is, maintenance can be performed on the mold portion corresponding to one processing stage before the portion of the mold corresponding to that processing stage significantly affects the deterioration of the mold portion corresponding to another processing stage, thereby preventing product defects and achieving high productivity. In other words, rather than detecting the occurrence of product defects or mold deterioration, the timing and frequency of maintenance are managed by a specified number of shots that are predicted to occur before these occur, and even before the deterioration linkage causes adverse effects on other processing stages.

[0040] Furthermore, it is preferable to adjust the maintenance information to a more appropriate value as production continues. For example, the number of shots on which maintenance was performed and the number of shots on which defects occurred are accumulated as production history, and the specified number of shots is updated based on this. Specifically, when maintenance is performed, the management device 20 accepts external input and stores the number of shots at that time in the memory unit 22. The maximum, minimum, or average value of the number of shots thus stored is compared with the specified number of shots. If it is desired to further reduce the occurrence of defects, the specified number of shots is reduced based on the average number of shots, etc. Conversely, if it is desired to reduce the frequency of maintenance, the specified number of shots is increased. In this way, by utilizing the accumulated production history, it is possible to update the specified number of shots and adjust the maintenance information, thereby further improving productivity.

[0041] Even within a single machining stage, multiple machining processes, such as slit hole punching and round hole punching, are performed. Therefore, even within a single machining stage, the deterioration of corresponding mold parts at multiple machining locations may be interconnected, but the behavior and progression of the deterioration may differ. In other words, the frequency of maintenance required varies depending on the machining location. Therefore, it is also preferable to store maintenance information corresponding to each of the multiple machining locations within a machining stage in the memory unit 22 and count the number of shots individually for each. In other words, the maintenance information includes sets of different specified number of shots, different maintenance contents, and even different machining contents for the same machining stage. This allows maintenance management to be performed not only on a machining stage-by-machine basis, but also on a machining location-by-machine basis.

[0042] Furthermore, the maintenance information may be adjusted by increasing the number of maintenance information entries while continuing production. For example, when a defective product (defective portion) is discovered, the stop device 15 stops the press processing device 1. Then, in response to the operation of the stop device 15, the management device 20 receives an external input of the processing stage or processing portion where the defective portion occurred and the corresponding maintenance content. That is, the worker performs maintenance on the portion of the mold corresponding to the discovered defective portion of the product, inputs the processing stage or processing portion and the maintenance content from the input device 29 according to the maintenance performed, and inputs a notice that the maintenance corresponding to the maintenance content was performed. It is also preferable to further include the reason for maintenance as the maintenance content, so that records of defective products can be accumulated, such as when maintenance information is externally input upon the discovery of a defective product. The reason for maintenance may be, for example, the type of defect that occurred, such as burrs, improper bending angles, improper bending dimensions, or dents.

[0043] The management device 20 receives this external input and checks whether a set of maintenance information including a specified number of shots that matches the processing stage or processing location with the maintenance content exists in the memory unit 22. If such a set of maintenance information exists (if maintenance management has already been performed), the management device 20 resets the corresponding number of shots in the counting unit 21 to zero. On the other hand, if such a set of maintenance information does not exist (if maintenance management has not been performed up to now), the management device 20 accepts further input of the number of shots based on this external input, creates a new set of maintenance information and registers it in the memory unit 22, and also creates a corresponding counter in the counting unit 21 and starts counting from zero.

[0044] In this way, the influence of mold deterioration between processing stages or between processing locations can be further suppressed, and high productivity can be achieved by preventing the occurrence of defective products.

[0045] Although the embodiments of the present invention and modifications based thereon have been described above, the present invention is not necessarily limited to these, and a person skilled in the art will be able to find various alternative embodiments and modifications without departing from the spirit of the present invention or the scope of the appended claims. [Explanation of symbols]

[0046] 1 Press processing equipment 2 Progressive press processing system 12 Progressive press die 13 Processing stage 15 Stop device 20 Management device 21 Counting Department 22 Memory section

Claims

1. A progressive press working method using a press working device, including a maintenance process for a progressive press die having a plurality of working stages provided at equal intervals in sequence along a feed line for a workpiece, The management device that notifies the operator that the maintenance process should be performed includes a counting unit that counts the number of shots for each of the processing stages after processing starts, and a storage unit that records maintenance information consisting of a set of a specified number of shots and maintenance content for each of the processing stages, The management device a progressive press working method characterized in that, when the specified number of shots for any of the groups in the maintenance information is reached, an operator is notified that the maintenance process should be performed, along with the processing stage corresponding to the group and the maintenance content, and the corresponding number of shots in the counting unit is reset.

2. 2. The progressive press working method according to claim 1, wherein the maintenance information includes sets of different specified numbers of shots and different maintenance contents for the same working stage.

3. 3. The progressive press working method according to claim 2, wherein the management device, in response to the operation of a stopping device that stops the press working device when a defective product is found in a processed product manufactured by the press working device, accepts external input of the processing stage that caused the defective part in the defective product and maintenance content corresponding to the defective part, and then, when further input is received to the effect that this maintenance content has been carried out, resets the corresponding number of shots in the counting unit if the pair that matches the processing stage and the maintenance content based on the external input exists in the memory unit, and if not exists, accepts further input of the number of shots based on the external input, creates the new pair, and registers it in the memory unit.

4. A progressive press working system using a press working device including a maintenance process for a progressive press die in which a plurality of working stages are provided in sequence at equal intervals along a feed line of a workpiece, The management device that notifies the operator that the maintenance process should be performed includes a counting unit that counts the number of shots for each of the processing stages after processing starts, and a storage unit that records maintenance information consisting of a set of a specified number of shots and maintenance content for each of the processing stages, The management device a progressive press processing system characterized in that, when the specified number of shots for any of the groups in the maintenance information is reached, an operator is notified that the maintenance process should be performed, along with the processing stage corresponding to the group and the maintenance content, and the number of shots corresponding to the counting unit is reset.

5. 5. The progressive press working system according to claim 4, wherein the maintenance information includes sets of different specified numbers of shots and different maintenance contents for the same working stage.

6. 6. The progressive press working system according to claim 5, wherein the management device, in response to the operation of a stopping device that stops the press working device when a defective product is found in a processed product manufactured by the press working device, accepts external input of the processing stage that caused the defective part in the defective product and maintenance content corresponding to the defective part, and then, when further input is received to the effect that this maintenance content has been carried out, resets the corresponding number of shots in the counting unit if the pair that matches the processing stage and the maintenance content based on the external input exists in the memory unit, and if not exists, accepts further input of the number of shots based on the external input, creates the new pair, and registers it in the memory unit.

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