The present disclosure relates to a method for manufacturing a press-molded product and a press line.
Background technology
[0002]
In press molding, there is a technology to improve the dimensional accuracy of press molded products by making a part of the mold movable. For example, Japanese Patent No. 6179696 (Patent Document 1) discloses a press device including a die provided with a die pad and a punch arranged opposite to the die and provided with an inner pad. There is.
Prior art literature
Patent documents
[0003]
Patent Document 1: Japanese Patent No. 6179696
Outline of the invention
Problems to be solved by the invention
[0004]
In press molding, all plate materials in the same production lot are press molded under preset press conditions. That is, if the deviation of the shape of the first press-molded product from the target shape is within the tolerance, the subsequent press molding is also performed under the same press conditions as the press conditions of the first press-molded product.
[0005]
The inventors have found that when the characteristics of a plurality of plate materials vary, even if the shape of the press-molded product first press-molded is the desired shape, the press-molded product to be press-molded later does not have the desired shape. I noticed that there is.
[0006]
This specification discloses a method for manufacturing a press-molded product and a press line, which can reduce deviations or variations in the shapes of a plurality of press-molded products from the target shape.
Means to solve problems
[0007]
The method for producing a press-molded product according to an embodiment of the present invention is to obtain the amount of warpage of one or a plurality of plate materials to be pressed individually for each plate material, for a die, a punch, and both the die and the punch. On the other hand, it includes press-molding the plate material into a press-molded product by a movable die whose relative position can be changed. In the press molding, the initial position of the movable die with respect to the die or the punch is controlled based on the amount of warpage of the plate material.
The invention's effect
[0008]
According to the present disclosure, it is possible to reduce deviations or variations in the shapes of a plurality of press-molded products from the target shape.
A brief description of the drawing
[0009]
[Fig. 1] Fig. 1 is a diagram showing a configuration example of a press line in the present embodiment.
FIG. 2 is a perspective view showing a configuration example of a press device.
FIG. 3A is a diagram for explaining an example of the relationship between the measurement direction of the warp amount of the press target plate and the direction of the punch ridge line.
FIG. 3B is a diagram for explaining an example of measuring the amount of warpage of the press target plate in the x direction in FIG. 3A.
[Fig. 3C] Fig. 3C is a diagram for explaining another measurement example of the warp amount of the press target plate.
FIG. 4A is a diagram showing an example of press molding.
[FIG. 4B] FIG. 4B is a diagram showing an example of press molding.
[Fig. 4C] It is a figure which shows the example of press molding.
[Fig. 4D] It is a figure which shows the example of press molding.
FIG. 5 is a cross-sectional view showing an example of a press-molded product.
[Fig. 6] Fig. 6 is a flow chart showing an operation example of the controller.
FIG. 7 is a graph showing an example of the correlation between the amount of protrusion of the inner pad and the shape of the press-molded product.
FIG. 8 is a graph showing an example of the relationship between the appropriate protrusion amount of the inner pad and the warp amount in the width direction of the blank.
FIG. 9 is a graph showing an example of the relationship between the appropriate protrusion amount of the inner pad and the warp amount in the longitudinal direction of the blank.
FIG. 10 is a histogram of the warp amount and the position accuracy of the flange when feedforward control is performed based on the warp amount.
FIG. 11 is a histogram of the warp amount and the position accuracy of the flange when feedforward control based on the warp amount is not performed.
Embodiment for carrying out the invention
[0010]
The plate material before press molding may be slightly warped. For example, the amount of warpage of a plurality of plate materials contained in the same production lot is often different. The inventor paid attention to the amount of warpage of this plate material. As a result of investigating the relationship between the amount of warpage of the plate material before press molding and the shape of the press-molded product after press molding, it is possible that variations in the amount of warpage of multiple plate materials can cause variations in the shape of the press-molded products. all right. In particular, it was found that when the grooved member is formed by press forming, the amount of warpage of the plate material before press forming tends to affect the shape of the grooved member after press forming.
[0011]
Therefore, we examined a method to suppress the variation in the shape of the press-molded product due to the variation in the amount of warpage of multiple plate materials. As a result of diligent studies, it was found that there is a correlation between the amount of warpage of the plate material before press forming and the initial position of the movable die used for press forming with respect to the die or punch. Based on this finding, we attempted to control the initial position of the movable die with respect to the die or punch in press forming according to the amount of warpage of the plate material. It has been found that the variation in the shape of the press-molded product can be suppressed by controlling the initial position of the movable die based on the amount of warpage. As a specific example, the following embodiment was conceived.
[0012]
(Method 1)
The method for producing a press-molded product according to an embodiment of the present invention is to obtain the amount of warpage of one or a plurality of plate materials to be pressed individually for each plate material, for a die, a punch, and both the die and the punch. On the other hand, it includes press-molding the plate material into a press-molded product by a movable die whose relative position can be changed. In the press molding, the initial position of the movable die with respect to the die or the punch is controlled based on the amount of warpage of the plate material.
[0013]
According to the above manufacturing method, the initial position of the movable die at the time of press molding with respect to the die or punch is controlled according to the amount of warpage of the plate material. By controlling this initial position, the shape of the press-molded product is adjusted according to the amount of warpage of the plate material. Therefore, it is possible to suppress deviation or variation in the shape of the plurality of press-molded products from the target shape due to the variation in the amount of warpage of the plurality of plate materials.
[0014]
The initial position of the movable die is the relative position of the movable die with respect to the die or punch at the initial stage of each of the plurality of press moldings. In each press molding, the press molding is performed by bringing the die and the punch relatively close to each other from the state where the movable die at the initial position is in contact with the plate material. The initial position of the movable mold is the position of the movable mold before the operation of bringing the die and the punch relatively close to each other.
[0015]
For example, the movable die may come into contact with a portion of the press-molded product (finished product) during press molding. In this case, the movable die controls the shape of the press-molded product (finished product). The initial position of the movable die can control the delicate shape of the product part of the press-molded product.
[0016]
The movable die may move relative to the die or punch during one press molding. Examples of possible dies of this type include punch pads (inner pads), die pads, blank holders, and the like. Alternatively, the movable die may be one in which the relative position with respect to the die or punch is fixed during one press molding. That is, the movable die may be one that does not move (do not operate) with respect to the die or punch during one press molding. It should be noted that one press molding is a press molding performed by a set of a set of a die, a punch and a movable die in order to make one press-molded product.
[0017]
(Method 2)
In the above method 1, the press molding may include continuously press molding a plurality of plate materials. In at least one of a plurality of continuous press moldings, the initial position of the movable die with respect to the die or the punch may be controlled based on the amount of warpage of the plate material. This makes it possible to suppress variations in the shape of the press-molded products due to variations in the amount of warpage in a plurality of press-molded products produced by a plurality of continuous press moldings.
[0018]
(Method 3)
The method for manufacturing a groove-shaped member according to an embodiment of the present invention is to manufacture a groove-shaped member having a top plate, vertical walls extending from both ends of the top plate, and a ridge line between the top plate and the vertical wall. The method. The manufacturing method obtains the amount of warpage of the plate material, arranges the plate material between a die and a punch having an inner pad at the top, and obtains an initial position of the inner pad with respect to the punch. With the setting based on the amount of warpage and the initial position of the inner pad with respect to the punch, the die and the punch are relatively close to each other, and the die shoulder of the die slides on the plate material. It includes forming the vertical wall and molding the top plate by sandwiching the plate material between the top of the punch containing the inner pad and the die.
[0019]
According to the above manufacturing method, the initial position of the inner pad with respect to the punch during press forming is set based on the amount of warpage of the plate material. An appropriate initial position is set according to the amount of warpage of the plate material. In this way, with the initial position of the inner pad set based on the amount of warpage, the die and the punch are relatively close to each other, and the vertical wall is formed while sliding the plate material with the die mold. Further, with the inner pad housed in the punch, the top plate is formed by sandwiching and pushing the plate material between the punch and the die. As a result, the shape of the groove-shaped member to be press-formed is adjusted according to the amount of warpage by controlling the initial position of the inner pad according to the amount of warpage of the plate material. As a result, it is possible to suppress deviations and variations in the shapes of the plurality of press-molded products from the target shape due to variations in the amount of warpage of the plurality of plate materials in the production lot.
[0020]
As an example, the punch includes a convex portion that protrudes toward the die. The die includes a recess corresponding to the protrusion of the punch. The movable die is provided, for example, in at least one of the convex portion of the punch and the concave portion of the die. This is an example of a movable mold. The inner pad, which is an example of the movable mold, is provided on the top of the convex portion of the punch. The inner pad is provided so as to be able to protrude from the top of the punch toward the die and to be stored in the top of the punch. The initial position of the inner pad may be set, for example, by the allowance from the punch of the inner pad. The allowance for the inner pad is the height of the inner pad protruding from the top of the punch. A die pad, which is an example of a movable mold, is provided at the bottom of a recess of the die. The die pad is provided so as to project from the bottom of the recess of the die toward the punch.
[0021]
The amount of warpage of the plate material may be measured by measuring the amount of warpage in at least one direction. From the viewpoint of suppressing deviation and variation from the target shape of the press-molded product due to the warp of the plate material, it is preferable to measure the warp amount of the plate material in two or more different directions. For example, the amount of warpage of the plate material may be measured in two different directions in the plane of the plate material.
[0022]
The plate material for which the amount of warpage is measured is a plate before press molding using a punch with a die and an inner pad. As the plate material, for example, the amount of warpage of a blank (flat plate) may be measured, or the amount of warpage of an intermediate molded product obtained by intermediately molding a blank may be measured. The total amount of warpage of the plate material may be measured, or a part of the amount of warpage may be measured. For example, the amount of warpage of a portion of the plate material that becomes a vertical wall may be measured. The amount of warpage is measured with respect to a plate material or a part thereof which should be originally flat (that is, the amount of warpage is 0). For example, the amount of warpage can be the amount of deviation with respect to a plane.
[0023]
(Method 4)
In the above method 3, it is preferable to measure the amount of warpage of the plate material as the first warp amount in the extending direction of the ridgeline and the second warp amount in the direction perpendicular to the ridgeline. This makes it possible to control the initial position of the inner pad with respect to the punch based on the amount of warpage in a direction that tends to affect the shape of the groove-shaped member. It is possible to further suppress deviations and variations in the shapes of a plurality of press-molded products from the target shape.
[0024]
(Method 5)
In any of the above methods 1 to 4, the correlation data showing the correlation between the amount of warpage of the plate material and the initial position of the movable mold with respect to the die or the punch is acquired, and the correlation data is used. It may further include setting the initial position of the movable mold corresponding to the amount of warpage of the measured plate material. By using the correlation data, it is possible to efficiently determine the set value of the initial position of the movable mold corresponding to the amount of warpage of the plate material.
[0025]
(Method 6)
In the above method 3 or 4, in the press molding, the die shoulder of the die is the said.The vertical wall may be formed while sliding the plate material over a length of 25 times or more the plate thickness of the plate material.
[0026]
In the pressing process for forming the vertical wall of the groove-shaped member, when the length of the die shoulder sliding with the plate material is 25 times or more the plate thickness of the plate material, the shape of the groove-shaped member changes due to the warp of the plate material. It has been found by the inventors that it is likely to occur. When the sliding distance of the die shoulder during molding of the vertical wall is 25 times the plate thickness of the plate material, the effect of suppressing deviation and variation from the target shape of the press-molded product due to the amount of warpage becomes greater.
[0027]
In any of the above methods 1 to 6, the tensile strength of the portion having the highest strength in the plate material may be 980 MPa or more. Generally, when the plate material has a high strength of 980 MPa or more, the variation in the amount of warpage tends to be larger than in the case of a low strength. By applying any of the above methods 1 to 6 to a plate material having a strength of 980 MPa or more, it is possible to suppress deviation or variation from the target shape of the press-molded product in press molding of such a high-strength press target material. Can be done. The plate material can be a metal plate. As an example, the plate material may be a steel plate.
[0028]
(Structure 1)
In the press line according to the embodiment of the present invention, the warp amount acquisition device for individually acquiring the warp amount of one or a plurality of plate materials to be pressed for each plate material, and for both the die, the punch, the punch, and the die. It includes a press device having a movable mold that can be moved relative to each other, and a controller that controls the press device. The controller is the die of the movable die or the die based on the warp amount of the plate material acquired by the warp amount acquisition device in the press molding of the plate material by the die, the punch and the mold of the press device. Controls the initial position with respect to the punch.
[0029]
According to the above configuration 1, the initial position of the movable die with respect to the die or punch at the time of press forming of each plate material is controlled according to the amount of warpage of each plate material. By controlling this initial position, the shape of the press-molded product is adjusted according to the amount of warpage of the plate material. Therefore, it is possible to suppress deviation or variation in the shape of the plurality of press-molded products from the target shape due to the variation in the amount of warpage of the plurality of plate materials.
[0030]
(Structure 2)
In the configuration 1, the warp amount acquisition unit may be a warp amount measuring device for measuring the warp amount of the plate material. As a result, the individual warpage amount of the plate material to be pressed can be efficiently obtained.
[0031]
(Structure 3)
In the configuration 2, the punch has a top and a side wall, and a punch ridge line between the top and the side wall, and the warp measuring direction of the warp amount measuring device is a direction parallel to the punch ridge line and the above. It may include a direction perpendicular to the punch ridge. This makes it possible to control the initial position of the movable die based on the amount of warpage in a direction that tends to affect the shape of the press-molded product.
[0032]
(Structure 4)
In any of the above configurations 1 to 3, the height of the side wall of the punch may be 25 times or more the minimum gap between the punch and the die. In this case, when the die and the punch are relatively close to each other and the plate is press-formed with the initial position of the movable die fixed, the sliding distance between the die shoulder and the plate is 25 times the plate thickness of the plate. It is easy to become the above. Therefore, the effect of suppressing deviation and variation from the target shape of the press-molded product due to the amount of warpage becomes greater. The minimum gap is the distance in the press direction of the gap between the die and the punch at the bottom dead center of molding. The press direction is the direction of relative movement of the die with respect to the punch.
[0033]
In the above configurations 1 to 4, the press line may further include the warp amount measuring device and a controller connected to the press device. The controller has access to a storage device that stores correlation data showing the correlation between the amount of warpage of the plate material and the initial position of the movable mold with respect to the die or the punch.
[0034]
The press line in the embodiment of the present invention includes a press device, a warp amount measuring device, the warp amount measuring device, and a controller connected to the press device.
The press device includes a die and a punch. The punch has a top and a side wall, a punch ridge between the top and the side wall, and an inner pad provided on the top.
The warp measuring direction of the warp amount measuring device includes a direction parallel to the punch ridge line and a direction perpendicular to the punch ridge line.
The controller has a warp amount of the plate material measured by the warp amount measuring device in a direction parallel to the punch ridge line, a warp amount in a direction perpendicular to the punch ridge line, and an allowance for the inner pad to be ejected from the punch. A storage device for storing correlation data showing the correlation is provided.
[0035]
In the above configuration, the warp measuring direction of the warp amount measuring device includes a direction parallel to the punch ridge line and a direction perpendicular to the punch ridge line. The warp amount measuring device can measure the warp amount of the plate material. The warp amount measuring device is configured to measure the warp amount in the direction corresponding to the punch ridge line of the plate material and the direction corresponding to the direction perpendicular to the punch ridge line. The direction corresponding to the punch ridge line of the plate material is the direction of the punch ridge line with respect to the plate material when the plate material is press-formed by the press device. The press device can measure the amount of warpage of the plate material in the direction of the punch ridge line and the direction perpendicular to the punch ridge line when the plate material is press-formed.
[0036]
Since the controller is connected to the warp amount measuring device and the press device, the warp amount measured by the warp amount measuring device can be used to control the initial position of the movable die with respect to the die or punch in the press molding of the press device. Further, the controller can determine the initial position of the movable mold corresponding to the warp amount of the plate material measured by the warp amount measuring device by using the correlation data stored in the storage device.
[0037]
According to the above configuration, the initial position of the movable die in press molding (for example, the allowance from the punch of the inner pad) can be controlled based on the amount of warpage of the plate material in the direction that easily affects the shape of the press-molded product. .. Therefore, it is possible to suppress deviation from the target shape and variation in shape of the plurality of press-molded products due to variation in the amount of warpage of the plurality of plate materials.
[0038]
The warp amount measuring device is configured to be able to measure the warp amount of the plate material upstream of the press device. The controller is the initial position of the movable die with respect to the die or punch when press-molding the plate material or the intermediate molded product which is a processed product obtained by deforming the plate material based on the warp amount of the plate material measured by the warp amount measuring device. To control. For example, the controller press-molds the plate material by bringing the die and the punch relatively close to each other with the inner pad protrusion allowance (for example, the amount of protrusion) fixed to the set amount at the initial position. May be determined based on the amount of warpage.
[0039]
The warp amount measuring device may be configured to measure the warp amount of the plate material before being placed in the press device, or may be configured to measure the warp amount of the plate material placed in the press device. ..
[0040]
The controller may have a processor and a storage device. The processor executes the program stored in the storage device. Even if the program is a program that causes the processor to perform a process of controlling the initial position of the possible mold punch or die when the plate material is press-formed based on the warp amount of the plate material measured by the warp amount measuring device. good.
[0041]
[Embodiment]
(Press line)
FIG. 1 is a diagram showing a configuration example of the press line 100 in this embodiment. The press line 100 shown in FIG. 1 includes a transfer device 4, an intermediate forming press device 3, a press device 5, a warp amount measuring device 10, and a controller 11. The warp amount measuring device 10 is arranged upstream of the press device 5 and the intermediate forming press device 3. The warp amount measuring device 10 measures the warp amount of the press target plate (blank) A, which is a flat plate material. The transport device 4 transports the blank A to the intermediate forming press device 3. The intermediate molding press device 3 deforms the blank A into an intermediate molded product. In this example, the intermediate molded product press-molded by the intermediate forming press device 3 is press-molded into a groove-shaped member by the press device 5. The transfer device 4 conveys the intermediate molded product, that is, the press target plate B from the intermediate forming press device 3 to the press device 5.
[0042]
The transport device 4 may be, for example, a conveyor having a transport path leading to the intermediate forming press device 3 or the press device 5. In this case, the transport path of the transport device 4 to the intermediate forming press device 3 may be arranged so as to pass through the measurement region of the warp amount measuring device 10. The transport device 4 is not limited to the conveyor. For example, the transfer device 4 may be a manipulator composed of an articulated robot. The manipulator transfers, for example, a material table arranged upstream of the intermediate forming press device 3 or the press device 5, or a plate material placed on a mold to the press device 5. The warp amount measuring device 10 may be arranged on the material table or in a manipulator so that the warp amount of the press target plate can be measured. The transport device 4 may be an unmanned operation or a manned operation forklift.
[0043]
The press device 5 press-molds the press target plate B into a press-molded product C. Hereinafter, the "press target plate A" and the "press target plate B" are simply referred to as "plate material A" and "plate material B". In this example, the press-molded product C is a groove-shaped member. The press device 5 has a die 6, a punch 7, a die side pad 8, and a punch side inner pad 9 as a die. The die-side pad 8 and the punch-side inner pad 9 can change their relative positions with respect to both the die 6 and the punch 7. The press device 5 arranges the plate material B between the die 6 and the punch 7, and presses the plate material B from both the die 6 and the punch 7 to press-mold the plate material B.
[0044]
Specifically, the press device 5 press-molds the plate material B between the die 6 and the punch 7 while pushing the punch 7 inside the die 6 by the relative movement of the die 6 and the punch 7. In the press molding process for making one press-molded product, the punch-side inner pad 9 is in contact with the plate material B, and the relative position between the punch-side inner pad and the punch 7 is fixed at the set position (initial position). A step (first press step) of pushing the plate material B by the die 6 and the punch 7 by bringing the die 6 and the punch 7 relatively close to each other is included. Further, the press forming step includes a step (second pressing step) of press forming the plate material B by bringing the die 6 and the punch 7 relatively close to each other while accommodating the punch side inner pad 9 in the punch 7. The press forming step further includes a step (third pressing step) of pressing the plate material B between the punch 7 and the die 6 to press the plate material B in a state where the punch side inner pad 9 is housed in the punch 7. ..
[0045]
The groove-shaped member of the press-molded product C includes a top plate, a vertical wall adjacent to the top plate, and a ridgeline between the top plate and the vertical wall. In the first pressing step and the second pressing step, a vertical wall is mainly formed. In the third press process, the top plate is mainly formed.
[0046]
The warp amount measuring device 10 may be configured to measure the warp amount from, for example, an image of the side surface of the plate material acquired from the side surface of the plate material by using an optical sensor. Alternatively, the warp amount measuring device 10 may be configured to measure the warp amount of the plate material by measuring the shape of the front surface, the back surface thereof, or both surfaces thereof using a camera or a laser displacement meter. For the measurement of the surface shape of the plate material, for example, a light cutting method, a phase shift method, a stereo matching method, or the like can be used. The warp amount measuring device 10 may measure, for example, the maximum value of the displacement amount of the surface of the plate material from the reference plane as the warp amount of the plate material. As an example, it is possible to access from one side of a plate material with a laser displacement meter and measure the angle of inclination in one direction of two portions separated by a certain distance by an optical cutting method. This angle can be converted into the amount of warpage.
[0047]
The warp amount measuring device 10 is configured to measure the warp amount of the plate material in two or more directions. The warp amount measuring device 10 is, for example, in the plane of the plate material.It is configured to measure the amount of warpage of the plate material in two directions orthogonal to each other. For example, the warp amount measuring device 10 measures the warp amount of the plate material in each of the direction of the line that becomes the ridge line of the groove type member when the plate material is press-molded into the groove type member and the direction perpendicular to the line. It may be configured to do so.
[0048]
The controller 11 is connected to the press device 5 and the warp amount measuring device 10. Here, the connection between the controller 11 and the press device 5 and the warp amount measuring device 10 may be wired or wireless. The controller 11 can communicate with the press device 5 and the warp amount measuring device 10. The controller 11 may be built in the press device 5 or the warp amount measuring device 10, or may be a device independent of these.
[0049]
The controller 11 can be configured by, for example, a computer including a processor 11a and a storage device 11b (memory). The processor 11a can realize the function of the controller 11 by executing the program stored in the storage device 11b. The controller 11 uses the data on the warp amount of the plate material (blank) A measured by the warp amount measuring device 10 to set the initial position with respect to the die or punch of the movable die in press forming (for example, the punch of the punch side inner pad 9). The relative position with respect to 7, that is, the allowance of the inner pad 9 from the punch 7) is controlled. Specifically, the controller 11 sets the initial position of the movable mold based on the data regarding the warp amount of the plate material (blank) A measured by the warp amount measuring device 10.
[0050]
Here, the initial position of the movable die set by the controller 11 is, for example, that the die 6 and the punch 7 are relatively close to each other with the allowance from the punch 7 of the punch side inner pad 9 fixed at the set value. The above-mentioned set value at the time of press molding (the above-mentioned first press step) can be used. That is, the set value of the delivery allowance in the first press process is controlled by the controller 11.
[0051]
The controller 11 uses, for example, correlation data showing the correlation between the amount of warpage recorded in advance in the storage device 11b and the initial position of the movable mold, and the initial position of the movable mold according to the measured amount of warpage ( It is possible to determine the control of the punch-side inner pad output allowance from the punch). The correlation data shows the correspondence between the initial position of the movable die (for example, the allowance from the punch 7 of the punch side inner pad 9 at the time of press forming (for example, in the first press step)) and the amount of warpage of the plate material. It is the data to show. Specifically, even if the correlation data is data showing the correlation (correspondence relationship) between the value indicating the amount of warpage of the plate material obtained by the measurement and the value controlling the initial position of the movable die in press forming. good. The data format of the correlation data is not particularly limited. The correlation data may be data (for example, table data, map data, etc.) that associates a value indicating the amount of warpage of the plate material with a value for controlling the initial position of the movable mold. Alternatively, the correlation data is data indicating a processing procedure of a processor that calculates a value for controlling the initial position of the movable mold by using a value indicating the amount of warpage of the plate material (for example, a function, a program, or parameters thereof, etc.). ) May be. Correlation data includes, for example, the amount of warpage of a plurality of plate materials (for example, test blanks) measured in the past, the initial position of the movable die when those plates are press-molded, and the press-molded product obtained by press molding. Can be created based on the shape of.
[0052]
For example, the controller 11 acquires data indicating the measured warp amount of the plate material (blank) A from the warp amount measuring device 10. The controller 11 uses the correlation data to convert a value indicating the amount of warpage of the plate material (blank) A into a control value indicating the initial position of the movable mold. The controller 11 controls the press device 5 so that the initial position of the movable die at the time of press molding becomes the position indicated by the control value.
[0053]
The press device 5 manufactures a plurality of press-molded products by repeating press-molding on a plurality of plate materials B obtained by processing a plurality of blanks A included in a production lot, for example. In the press molding of each of the plurality of plate materials B, the controller 11 may set the initial position of the movable die. The controller 11 uses data indicating the amount of warpage of the original blank A of the plate material B to set the initial position of the movable die in the press forming of one plate material B. This enables feedforward control of the initial position of the movable mold according to the amount of warpage of the blank A. The warp amount measuring device 10 may measure the warp amount of the plate material B, which is an intermediate molded product, instead of the blank A. In this case, the controller 11 sets the initial position of the movable mold according to the amount of warpage of the plate material B, which is an intermediate product.
[0054]
(Configuration example of press device and warp amount measuring device)
FIG. 2 is a perspective view showing a configuration example of a press device 5 having a movable die. In the example shown in FIG. 2, the movable mold has a die 6 having a concave portion, a punch 7 having a convex portion corresponding to the concave portion of the die 6, and a die side that is relatively movable with respect to the die 6 and the punch 7. The pad 8 and the punch side inner pad 9 are included. The die-side pad 8 forms a part of the recess of the die 6 and can protrude toward the punch 7 with respect to the recess of the die 6. The punch-side inner pad 9 forms a part of the convex portion of the punch 7 and can project to the die 6 side with respect to the convex portion of the punch 7.
[0055]
The convex portion of the punch 7 includes a top portion 7c, a side wall 7d adjacent to the top portion 7c, and a punch ridge line 7b between the top portion 7c and the side wall 7d. In the example shown in FIG. 2, a plurality of punch-side inner pads 9 are provided. The plurality of punch-side inner pads 9 are arranged so as to be spaced apart from each other in the extending direction of the punch ridge line 7b. The punch side inner pad 9 may be provided in the punch 7 over the entire extending direction of the punch ridge line 7b.
[0056]
The recess of the die 6 includes a bottom 6a, a side wall 6b adjacent to the bottom 6a, and a die shoulder 6c which is the edge of the recess. The die shoulder 6c forms a die ridge. The extending direction of the die ridge line is substantially the same as the extending direction of the punch ridge line 7b. A plurality of die side pads 8 are provided. The plurality of die-side pads 8 are provided at positions corresponding to the plurality of punch-side inner pads 9. The plurality of die-side pads 8 are arranged at intervals from each other in a direction perpendicular to the transport direction of the plate material. The die side pad 8 may be provided on the die 6 over the entire extending direction of the punch ridge line 7b.
[0057]
The plate material B is conveyed between the die 6 and the punch 7. The transport direction F of the plate material B is substantially perpendicular to the extending direction of the punch ridge line 7b and the die shoulder 6c. The plate material B is arranged between the die 6 and the punch 7, and is pressed from the die 6 and the punch 7 to be press-formed. By press molding, the plate material B becomes a groove-shaped member. In the press forming process, the die shoulder 6c slides on the plate material B while pushing the plate material B for forming. Further, the plate material B is pressed against the punch ridge line 7b, and the ridge line is formed on the plate material B. Therefore, the extending direction of the ridge line between the top plate and the vertical wall of the groove-shaped member to be press-molded corresponds to the extending direction of the punch ridge line 7b.
[0058]
The warp amount measuring device 10 measures the warp amount in the plate material (blank) A in the direction of the line on which the ridge line of the groove-shaped member is formed and in the direction perpendicular to the direction. That is, in the plate material (blank) A, the warp amount in the direction of the line to which the punch ridge line 7b is to hit and the direction perpendicular to the direction is measured by press forming.
[0059]
FIG. 3A is a diagram for explaining an example of the relationship between the measurement direction of the warp amount of the blank A and the direction of the punch ridge line 7b in press molding. FIG. 3A is a top view of the blank A and the punch 7. In FIG. 3A, the plane of the blank A is the xy plane, and the direction perpendicular to the xy plane is the z direction. The x-direction and the y-direction are orthogonal to each other. In the example shown in FIG. 3A, the amount of warpage is measured in each of the two directions (x direction and y direction) orthogonal to each other in the plane of the blank A. The blank A is processed into a plate material B. The plate material B is arranged between the punch 7 and the die 6 in a state where one of the two directions (x direction and y direction) in which the amount of warpage is measured in the plate material B is the same as the extending direction of the punch ridge line 7b. Will be done. As a result, the amount of warpage in the extending direction of the ridgeline of the groove-shaped member and the amount of warpage in the direction perpendicular to the ridgeline of the groove-shaped member are measured.
[0060]
FIG. 3B is a diagram for explaining the measurement of the amount of warpage of the plate material (blank) A in the x direction in FIG. 3A. In the example shown in FIG. 3B, the displacement is measured from the reference surface KM on the surface of the plate material A at each point arranged in the x direction. For example, the amount of warpage in the x direction can be determined based on the maximum value S1 of the displacement amount on the reference surface KM and the maximum value of the displacement amount below the reference surface KM. The reference surface KM may be, for example, a surface set in advance in the measurement system of the warp amount measuring device 10, or a surface determined from the measurement positions of a plurality of points of the plate material A. In this way, the amount of warpage of the plate material in one direction can be measured by the distribution of the displacement of the plate material from the reference plane in one direction. Similarly, the amount of warpage in two or more directions can be measured.
[0061]
FIG. 3C is a diagram for explaining another example of measuring the amount of warpage of the plate material. In the example shown in FIG. 3C, the angle of the cross section in the xz plane of two portions of the plate material A separated by a specific distance K1 in the x direction is measured. The distance K1 may be, for example, about 110 mm. The length K2 of the portion to be measured in the x direction may be, for example, about 5 mm. The integrated value of the amount of warpage becomes the angle change. By measuring the change in angle, the average amount of warpage in a specific section can be measured. Alternatively, as another example, the z-coordinate values ​​of three points separated by a certain interval may be measured. In this case, assuming a uniform arcuate curve on the surface of the plate material, the average warpage amount can be obtained from the measured values ​​at three points. The method for measuring the amount of warpage is not limited to the above example.
[0062]
(Example of press molding)
FIGS. 4A to 4D are views showing an example of press molding. Here, as an example, an example of press molding by the press apparatus 5 shown in FIGS. 1 and 2 will be described. In the example shown in FIGS. 4A to 4D, the die side pad 8 is arranged inside the die 6 and can move in the pressurizing direction of the plate material. Here, the pressurizing direction of the plate material is the direction of relative movement of the die 6 with respect to the punch 7. The punch-side inner pad 9 can be arranged so as to project outward from the pressure surface 7a of the punch 7, and can be pushed to the same height as the pressure surface 7a of the punch 7. The upper surface (top surface) of the top portion 7c of the punch 7 is the pressure surface 7a.
[0063]
The punch side inner pad 9 is movable in the vertical direction (pressurizing direction) with respect to the punch 7 via, for example, a gas spring 9s or an elevating mechanism such as a cushion mechanism of a press machine. The die-side pad 8 is installed on the slide 6d of the press device via, for example, an elevating mechanism such as a gas spring 8s. A die 6 is fixed to the slide 6d. The die-side pad 8 can move in the vertical direction together with the slide 6d. The distance between the die side pad 8 and the slide 6d can be expanded and contracted by the gas spring 8s. The bottom portion 6a of the recess of the die 6 is provided with a recess in which the pad 8 on the die side is accommodated. The punch-side inner pad 9 is arranged inside a recess formed in the pressurizing surface 7a of the punch 7. Further, the punch-side inner pad 9 is urged upward by a gas spring 9s arranged inside the recess. Due to the urging of the gas spring 9s, the upper surface of the inner pad 9 on the punch side is in a state of protruding outward from the pressure surface 7a of the punch 7. The distance between the punch 7 and the punch-side inner pad 9 changes due to the expansion and contraction of the gas spring 9s.
[0064]
The die side pad 8 and the punch side inner pad 9 can move relative to the die 6 or the punch 7 in a state of being pressed against the plate material B. For example, the die 6 can be brought closer to the punch 7 while the die-side pad 8 and the punch-side inner pad 9 stand still with the plate material B sandwiched between them. Slide 6d or daWhen the die-side pad 8 and the punch-side inner pad 9 sandwiching the plate material B are stationary while the b-6 moves closer to the punch 7, the gas spring 8s (elevating mechanism) of the die-side pad 8 contracts. While the die 6 moves closer to the punch 7, the gas spring 8s (elevating mechanism) of the die side pad 8 does not expand or contract when the die side pad 8 moves closer to the punch 7.
[0065]
In the press device 5, the punch side inner pad 9 and the die side pad 8 are pressed against the plate material B in a state where the punch side inner pad 9 is projected outward from the pressure surface 7a of the punch 7, and the die 6 and the punch 7 are pressed. And are relatively close to each other, and the plate material B is press-molded. At the bottom dead center of molding, the plate material B is press-molded until the inner pad 9 on the punch side becomes the same height as the pressure surface 7a of the punch 7. At the bottom dead center of molding, the plate material B is sandwiched between the punch 7 and the die 6 in a state where the punch side inner pad 9 is housed in the punch 7 and the die side pad 8 is housed in the die 6.
[0066]
As a specific example, first, as shown in FIG. 4A, the die 6 and the die 6 and the die 6 are pressed against the plate material B in a state where the punch side inner pad 9 is projected outward from the pressure surface 7a of the punch 7. By lowering the die side pad 8, the plate material B is press-formed between the die 6 and the punch 7. At this time, the height (projection amount) H of the upper surface of the punch-side inner pad 9 with respect to the pressure surface 7a of the punch 7 is fixed to the set value. The protrusion amount H is set based on the warp amount of the blank A before processing the plate material B, which is measured before press forming. In the plate material B to be formed, slack Ba is generated in the plate material B according to the protrusion allowance (projection amount) H of the punch side inner pad 9 from the punch 7. Then, from this state, as shown in FIG. 4B, the press molding is continued by lowering the die 6 while controlling the slack Ba of the plate material B to a predetermined amount. As shown in FIG. 4C, the die 6 is lowered to H before the bottom dead center of molding (position at a distance H from the bottom dead center of molding). At this time, the die 6 is lowered while the pressurizing mechanism of the die side pad 8 is contracted.
[0067]
In the steps shown in FIGS. 4A to 4C, the die 6 and the punch 7 are relative to each other in a state where the protrusion allowance of the punch 7 from the punch side inner pad 9, that is, the protrusion amount H is fixed to the set value (value indicating the initial position). Get closer to the target. From the stage shown in FIG. 4C, that is, the stage in which the die-side pad 8 is completely retracted by being bottomed out with respect to the die 6 (the stage in front of the molding bottom dead center by the amount of protrusion H), the punch-side inner pad 9 The distance between the upper surface of the punch 7 and the pressure surface 7a of the punch 7 begins to shrink. From the stage of FIG. 4C to the stage of FIG. 4D, the relative position of the punch 7 with respect to the punch-side inner pad 9 changes. As shown in FIG. 4D, the plate material B is press-formed until the upper surface of the punch-side inner pad 9 has the same height as the pressure surface 7a of the punch 7. At this time, the slack Ba formed in the plate material B flows out toward the vertical wall portion between the punch 7 and the die 6 while receiving the in-plane compressive stress. Thereby, a press-molded product having a hat-shaped cross-sectional shape can be obtained.
[0068]
In the examples shown in FIGS. 4A to 4D, the bending region that contributes to the inward direction, that is, the spring go, is expanded by crushing the slack Ba formed in the plate material B and letting it flow out toward the vertical wall portion. As a result, it is possible to balance the spring back and the spring go of the work material to be press-molded. As a result, it is possible to reduce the shape defect of the vertical wall.
[0069]
Further, in the press forming process from FIG. 4A to FIG. 4D, the outer portion Bb of the plate material B sandwiched between the die side pad 8 and the punch side inner pad 9 slides with the die 6 and the punch 7. Be pressed. It is known that the warp of the portion Bb of the plate material that slides with the die 6 or the punch 7 in this press molding tends to affect the shape of the press molded product. Therefore, when the sliding distance between the die shoulder 6c of the die 6 and the plate material B is 25 times or more the plate thickness of the plate material B, the effect of controlling the feeding allowance H based on the amount of warpage becomes larger.
[0070]
In the above example, in the press forming on one plate material B, the die 6 is relatively close to the punch 7 in a state where the allowance from the punch 7 of the punch side inner pad 9 is fixed (the state of the initial press setting). A step of press-molding the plate material B and a step of press-molding the plate material B by changing the ejection allowance of the punch-side inner pad 9 from the punch 7 and bringing the die 6 relatively close to the punch 7. The protrusion allowance of the punch-side inner pad 9 from the punch 7 in the initial setting of the press, that is, the protrusion amount H of the punch-side inner pad 9, is controlled by the controller 11. The protrusion amount H is an example of a value indicating the initial position of the movable mold.
[0071]
The controller 11 determines the protrusion amount H of the punch side inner pad 9 based on the measured warp amount of the plate material (blank) A. In the example shown in FIG. 3A, the amount of warpage of the plate material (blank) A is measured in the extending direction of the ridgeline of the groove-shaped member of the press-molded product, that is, in the extending direction of the punch ridgeline 7b and the direction perpendicular to the extending direction. Thereby, the protrusion amount H of the punch side inner pad 9 can be controlled according to the warp amount of the plate material (blank) A in the direction that easily affects the shape of the press-molded product.
[0072]
Note that press molding using a movable die is not limited to the above example. For example, in the press device, the die side pad 8 may be omitted. Further, the above example is an example of press-molding a plate material B of an intermediate material which has been previously bent and molded, but the press apparatus may be one which press-molds a flat plate which is not bent and molded, that is, a blank A.
[0073]
Generally, in bending molding, the die side pad is often set to prevent misalignment of the plate material with respect to the punch side inner pad. In other words, the die-side pad may be omitted in a shape that does not easily shift. Even in the molding examples shown in FIGS. 4A to 4D, the die side pad 8 may be omitted. In the molding examples shown in FIGS. 4A to 4D, when the die side pad 8 is omitted, the portion corresponding to the die side pad 8 is stored in the recessed portion of the die 6 from the initial stage of molding to the stage shown in FIG. 4C. It becomes a state of being integrated with the die in the state where it is done. From the initial stage of molding to the stage shown in FIG. 4C, the central portion of the plate material B in the cross-sectional width direction is press-molded in a state of being lifted from the lower side by the punch-side inner pad 9 as in the case of having the die-side pad 8. Goes forward. After the step shown in FIG. 4C, the punch-side inner pad 9 is pushed downward by the die 6 to lower, and press forming is completed in the same manner as in FIG. 4D.
[0074]
(Example of press-molded product)
FIG. 5 is a cross-sectional view showing an example of a press-molded product. The press-molded product 12 shown in FIG. 5 is obtained, for example, by press-molding shown in FIGS. 4A to 4D. The press-molded product 12 is an example of a groove-shaped member. The press-molded product 12 has a hat-shaped cross section. The press-molded product 12 is a long member whose longitudinal direction is perpendicular to the cross section shown in FIG. A top plate 12A extending in the width direction of the press-molded product 12 and a pair of ridge lines 12B adjacent to both ends in the width direction of the top plate 12A are included. Further, the press-molded product 12 includes a pair of vertical walls 12C extending from the ridge line 12B to the back surface side (one side in the plate thickness direction) of the top plate 12A, and a pair of vertical walls 12C adjacent to the tips (lower ends) of the pair of vertical walls 12C. Includes ridgeline 12D. Further, the press-molded product 12 includes a pair of flanges 12E extending from the pair of ridge lines 12D to both sides of the top plate 12A in the width direction. The angle θ2 formed by the top plate 12A and the vertical wall 12C is 90 deg. Not limited to the case of. The angle θ2 is 90 to 125 deg. Can be exemplified. In the strong machining in this range, problems such as springback become apparent, so that the control of the feeding allowance based on the above-mentioned warp amount becomes effective. The angle θ2 is 90 deg. If the angle is less than that, it may interfere with removing the press-molded product from the mold.
[0075]
In the press-molded product 12, for example, the angle θ1 formed by the top plate 12A and the flange 12E may be measured. In this example, each θ1 formed by the top plate 12A and the flange 12E has a predetermined reference value θc indicating a desired shape, in this case 0 deg. If it is larger (θ1> θc = 0deg.), It becomes a springback, and if θ1 is smaller than the reference value θc (θ1 <θc = 0deg.), It becomes a spring go. The value indicating the degree of spring back or spring go is not limited to the angle θ1 in the above example. For example, the angle θ2 formed by the top plate 12A and the flange 12E, or the vertical height difference T1 of the bottom surface of the flange 12E may be measured as a value indicating the degree of springback or spring go.
[0076]
(Operation example)
FIG. 6 is a flow chart showing an operation example of the controller 11 in this embodiment. In the example shown in FIG. 6, first, the controller 11 initially sets the press conditions (S1). The pressing conditions include, for example, an initial position of the movable die with respect to the die or punch (for example, a allowance for the punch-side inner pad 9 to be ejected from the punch). As an example of the initial position of the movable die, the initial value of the protrusion amount H of the punch side inner pad 9 is set. The pressing conditions are not limited to the initial position of the movable die.
[0077]
The controller 11 acquires the correlation data obtained in advance (S2). For example, the controller 11 determines the correlation data used for feedforward processing and makes it accessible. For example, the correlation data used for processing is extracted from the data pre-recorded in the recording medium (internal or external storage device built in the controller 11) accessible to the computer of the controller 11 and stored in the memory (storage device 11b). do. The correlation data is created in advance before press molding and recorded on a storage medium accessible to the controller 11.
[0078]
In S3 of FIG. 6, the warp amount measuring device 10 then acquires the measurement result of the warp amount of the plate material B conveyed to the press device 5. The controller 11 acquires the measurement result of the warp amount of the plate material from the warp amount measuring device 10. As an example, as shown in FIGS. 1 and 2, the amount of warpage of the plate material (blank) A is measured upstream of the press device 5. The data indicating the amount of warpage of the plate material (blank) A is stored in, for example, a storage device accessible to the controller 11. The controller 11 acquires data indicating the amount of warpage of the plate material (blank) A, which is the source of the plate material B to be conveyed to the press device 5, from the storage device.
[0079]
The controller 11 sets the initial position of the movable die, for example, the protrusion allowance (protrusion amount H) for the punch of the punch side inner pad 9 based on the warp amount acquired in S3 (S4). The controller 11 controls the press device 5 to control the protrusion amount H of the punch side inner pad 9 with respect to the punch 7 to a value set based on the warp amount. The controller 11 executes press molding while controlling the protrusion amount H (S5). In S5, press molding is executed on the plate material B processed from the blank A for which the warp amount has been acquired in S3, with the protrusion allowance (protrusion amount H) of the punch side inner pad 9 set in S4.
[0080] [0080]
The processing of S3 to S5 in FIG. 6 is repeated for a plurality of plate materials contained in one production lot. This enables feedforward control based on the amount of warpage of the plate material in each of the press moldings of one production lot.
[0081]
Here, an example of correlation data will be described. The graph shown in FIG. 7 shows the relationship between the protrusion amount H of the punch-side inner pad 9 and the springback / spring go. The angle difference on the vertical axis of the graph is the angle θ1 and the reference value θc formed by the top plate 12A and the flange 12E of the press-molded product 12 shown in FIG. 5, in this case 0deg. The difference from (θ1-θc (here, θc = 0deg.)) Is shown. The reference value θc is the angle formed by the top plate and the flange 12E when there is no spring back and spring go. If the angle difference is positive, it is springback, and the angle difference is minor. In the case of Su, it is a spring go. In the relationship shown in the graph shown in FIG. 7, the appropriate value Ha of the protrusion amount of the punch side inner pad is the protrusion amount when the angle difference becomes 0.
[0082]
FIG. 8 is a graph showing an example of the relationship between the appropriate amount of protrusion and the amount of warpage in one direction of the blank. The vertical axis of the graph shown in FIG. 8 shows the protrusion amount of the punch side inner pad when the angle difference (θ1-θc) becomes 0, that is, when there is no spring bag and spring go. The horizontal axis indicates the amount of warpage in the width direction of the blank. Here, the width direction of the blank is a direction perpendicular to the ridgeline of the groove-shaped member and a direction corresponding to the direction perpendicular to the punch ridgeline. As shown in FIG. 8, the inventor has found that the amount of warpage in the width direction of the blank and the amount of proper protrusion of the punch-side inner pad are correlated with each other.
[0083]
FIG. 9 is a graph showing an example of the relationship between the appropriate protrusion amount and the warp amount in the other direction of the blank. The vertical axis of the graph shown in FIG. 9 shows the protrusion amount of the punch side inner pad when the angle difference (θ1-θc) becomes 0, that is, when there is no spring bag and spring go. The horizontal axis indicates the amount of warpage in the longitudinal direction of the blank. Here, the longitudinal direction of the blank is a direction corresponding to the extending direction of the ridgeline of the groove-shaped member and the extending direction of the punch ridgeline. As shown in FIG. 9, the inventor has found that the amount of warpage in the longitudinal direction of the blank and the amount of proper protrusion of the punch-side inner pad are correlated with each other.
[0084]
As an example, a control example of the protrusion amount when both the warp amount SW1 in the width direction of the blank and the warp amount SL1 in the longitudinal direction can be acquired will be described. In this case, from the sum (HW1 + HL1) of the proper protrusion amount HW1 with respect to the warp amount SW1 in the width direction obtained from the graph of FIG. 8 and the proper protrusion amount HL1 with respect to the warp amount SL1 in the longitudinal direction obtained from the graph of FIG. The value obtained by subtracting the appropriate protrusion amount Hao when there is no warp amount in both the direction and the width direction can be calculated as the protrusion amount H. The controller 11 controls the press device 5 so that the set value of the protrusion allowance H from the punch 7 of the punch side inner pad 9 is (HW1 + HL1-Hao). In this case, for example, the formula representing the lines of the graphs shown in FIGS. 8 and 9 or the data showing each plot in the graph are used as the correlation data.
[0085]
As described above, the correlation data may include data showing the relationship between the amount of warpage in the width direction of the plate material and the amount of warpage in the longitudinal direction of the plate material and the appropriate value of the punch-side inner pad ejection allowance. By using such correlation data, the controller 11 can determine an appropriate protrusion amount based on the measured warp amount in the width direction and the longitudinal direction of the plate material. As a result, it is possible to more appropriately control the feeding allowance based on the amount of warpage of the plate material in the direction that tends to affect the press-molded product.
[0086]
(Example of plate material)
The material of the plate material to which the present invention can be applied is not particularly limited. As the material of the plate material, for example, a thin plate of 980 MPa class high strength steel sheets (High Tensile Strength Steel Sheets) may be used. In recent years, in order to reduce the weight of press-molded products, the strength of press-molded products has been increasing. In line with this, the strength of press-molded materials is increasing. As the strength of the material increases, it becomes difficult to press-mold it into a desired shape. For example, spring packs generally tend to be larger as the material becomes stronger. According to the above embodiment, even when a plate material having a tensile strength of 980 MPa or more is used, it is possible to reduce deviations and variations in the shapes of the plurality of press-molded products from the target shape.
[0087]
Further, in general, for example, between a steel sheet having a tensile strength of 270 MPa class and a steel sheet having a tensile strength of 1.2 GPa class, the variation in the amount of warpage tends to be larger in the steel sheet having a tensile strength of 1.2 GPa class. If the variation in the amount of warpage is large, the mold shape is adjusted, and even if the shape of the press-molded product that is press-molded at the beginning of the production lot is the desired shape, the press-molded product that is press-molded later in the production lot is also available. There is a high possibility that the target shape will not be achieved. According to the above embodiment, even when a plate material having a tensile strength of 980 MPa or more, which has a relatively large variation in material characteristics as compared with a low-strength steel plate, is used, the punch of the inner pad based on the amount of warpage is performed. By controlling the feedforward of the output allowance, it is possible to reduce the variation in the shape of a plurality of press-molded products.
[0088]
(Example)
FIG. 10 is a histogram showing the result of measuring the position accuracy of the flange when the protrusion amount H of the punch side inner pad 9 is feedforward controlled based on the warp amount. FIG. 11 is a histogram showing the result of measuring the position accuracy of the flange when the protrusion amount H of the punch side inner pad 9 is not feedforward controlled. In FIGS. 10 and 11, the histogram in the first row from the top shows the distribution of the amount of warpage in the width direction of the blank included in one test lot. The warpage in the width direction of the blank changes randomly for each shot of press molding in the range of about −0.0004 to 0.0006 mm -1. The histogram in the second row from the top shows the distribution of the amount of warpage in the longitudinal direction of the blank contained in one test lot. The warp of the blank in the longitudinal direction varies randomly from press-molded shot to shot in the range of about −0.0004 to 0.0004 mm-1. The histogram in the third row from the top shows the distribution of flange position accuracy in one test lot. The flange position accuracy is the height difference of the flange (corresponding to T1 shown in FIG. 5). For the flange position accuracy, the target reference position is 0.0. As the blank material, a steel plate having a tensile strength of 1180 MPa was used.
[0089]
In the results shown in FIG. 10, the standard deviation of the warp in the width direction of the blank is 0.00023 mm-1, and the standard deviation of the warp in the longitudinal direction of the blank is 0.00018 mm-1, which is the standard of flange position accuracy. The deviation was 0.12 mm.
[0090]
In the results shown in FIG. 11, the standard deviation of the warp in the width direction of the blank is 0.00024 mm-1, and the standard deviation of the warp in the longitudinal direction of the blank is 0.00016 mm-1, which is the standard of flange position accuracy. The deviation was 0.36 mm.
[0091]
From these results, by performing feedforward control that controls the protrusion allowance (protrusion amount) H of the punch side inner pad 9 from the punch 7 based on the amount of warpage of the blank, the shape of the press-molded product can be obtained from the target shape. It was found that the deviation and variation were suppressed.
[0092]
Although one embodiment of the present invention has been described above, the above-described embodiment is merely an example for carrying out the present invention. Therefore, the present invention is not limited to the above-described embodiment, and the above-mentioned embodiment can be appropriately modified and carried out within a range not deviating from the gist thereof.
[0093]
For example, in the above embodiment, the movable die that controls the initial position based on the amount of warpage is the inner pad of the punch, but the initial position of the die side pad provided on the die with respect to the die is controlled based on the amount of warpage. May be done.
[0094]
In the above embodiment, the warp amount acquisition device for acquiring the warp amount is a warp amount measuring device. The warp amount acquisition device may be a device that acquires data indicating the warp amount of each of the plurality of plate materials B to be pressed. For example, when the warp amount measuring device is located at a remote location, the warp amount acquiring device may be configured to receive data indicating the warp amount from the warp amount measuring device or another communication device. The warp amount acquisition device may be included in the controller. That is, the controller may be configured to acquire the amount of warpage from an external device. The data indicating the amount of warpage of each plate material is preferably data of the measured value of the amount of warpage, but the data indicating the amount of warpage is not limited to the data of the measured value.
Description of the sign
[0095]
4: Conveyor device
5: Press equipment
6: Die
7: Punch
8: Die side pad
9: Punch side inner pad (inner pad)
10: Warp amount measuring device
11: Controller
12: Press molded product
The scope of the claims
[Claim 1]
Obtaining the amount of warpage of one or more press target plates individually for each plate,
Includes press-molding the plate into a press-molded product with a die, a punch, and a movable die whose relative position can be changed with respect to both the die and the punch.
In the press molding, a method for manufacturing a press-molded product that controls the initial position of the movable die with respect to the die or the punch based on the amount of warpage of the plate material.
[Claim 2]
The press molding includes continuous press molding of a plurality of plate materials.
The method for manufacturing a press-molded product according to claim 1, wherein the initial position of the movable die with respect to the die or the punch is controlled based on the amount of warpage of the plate material in at least one of a plurality of continuous press moldings.
[Claim 3]
The press-molded product is a groove-shaped member having a top plate, vertical walls extending from both ends of the top plate, and a ridge line between the top plate and the vertical wall.
The movable mold includes an inner pad provided at the top of the punch.
Placing the plate material between the die and the punch with the inner pad on the top,
Setting the initial position of the inner pad with respect to the punch based on the acquired warp amount,
With the initial position of the inner pad with respect to the punch set, the die and the punch are relatively close to each other, and the die shoulder of the die slides on the plate material to form the vertical wall.
Forming the top plate by sandwiching the plate material between the top of the punch containing the inner pad and the die.
The method for producing a press-molded article according to claim 1 or 2, comprising the above.
[Claim 4]
The method for manufacturing a press-molded product according to claim 3, wherein as the warp amount of the plate material, the first warp amount in the extending direction of the ridge line and the second warp amount in the direction perpendicular to the ridge line are measured.
[Claim 5]
Obtaining correlation data showing the correlation between the amount of warpage of the plate material and the initial position of the movable mold with respect to the die or the punch, and
The press-molded product according to any one of claims 1 to 4, further comprising setting an initial position of the movable die corresponding to the warp amount of the plate material measured by using the correlation data. Manufacturing method.
[Claim 6]
The method for manufacturing a press-molded product according to claim 3 or 4, wherein the die shoulder of the die slides the plate material over a length of 25 times or more the plate thickness of the plate material to form the vertical wall.
[Claim 7]
A warp amount acquisition device that individually acquires the warp amount of one or more press target plates for each plate material,
A press device equipped with a die, a punch, and a movable die that can move relative to both the punch and the die,
Equipped with a controller to control the press device
In the press molding of the plate material by the die, the punch, and the movable die of the press device, the controller uses the die or the die of the movable die based on the warp amount of the plate material acquired by the warp amount acquisition device. A press line that controls the initial position with respect to the punch.
[Claim 8]
The press line according to claim 7, wherein the warp amount acquisition unit is a warp amount measuring device for measuring the warp amount of the plate material.
[Claim 9]
The punch has a top and a side wall, and a punch ridge between the top and the side wall.
The press line according to claim 8, wherein the warp measuring direction of the warp amount measuring device includes a direction parallel to the punch ridge line and a direction perpendicular to the punch ridge line.
[Claim 10]
The press line according to any one of claims 7 to 9, wherein the height of the side wall of the punch is 25 times or more the minimum gap between the punch and the die.
[Claim 11]
One of claims 7 to 10, wherein the controller has access to a storage device that stores correlation data indicating the correlation between the amount of warpage of the plate material and the initial position of the movable mold with respect to the die or the punch. The press line according to item 1.