JP2019051548A - Press molding method and press molding device - Google Patents

Abstract

To achieve both of suppression of occurrence of cracking of a work-piece and suppression of occurrence of wrinkles thereof.SOLUTION: The present invention is applied to a press molding method for performing press molding of a work-piece by a press die comprising an upper die and a lower die while holding the work-piece by a die cushion. This press molding method comprises a press process in which before a press position at which the work-piece is pressed by the press die reaches a press lower dead point, the press position is gradually lowered while repeating pressing and releasing of the work-piece by the press die plural times. In the press process, a pressing force such that the work-piece is held by the die cushion is controlled separately from a press molding force for press molding of the work-piece by the press die.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a press molding method and a press molding apparatus.

For forming automobile parts and the like, a method of press forming by sandwiching a metal plate as a workpiece in the vertical direction between an upper die and a lower die is often used (for example, see Patent Document 1).
In the press forming method described in Patent Document 1, for the purpose of suppressing the occurrence of cracks in the metal plate, after the punch (lower die) first contacts the metal plate and the forming is started, the punch reaches the end of the stroke. The operation of once separating the punch from the metal plate and forming the metal plate again by using the punch and the die (upper die) is performed at least once before reaching the completion of forming. .

  In addition, the press forming method described in Patent Document 1 forms a metal plate in a state where the metal plate is sandwiched between a wrinkle presser (die cushion) and a die for the purpose of suppressing the generation of wrinkles in the metal plate. doing.

JP 2005-199318 A

  However, the press forming method described in Patent Document 1 does not adjust the wrinkle pressing force by the wrinkle pressing. Therefore, even if the occurrence of cracks in the workpiece can be suppressed, the occurrence of wrinkles in the workpiece may not be suppressed, and there is a problem that it is impossible to achieve both suppression of occurrence of cracks in the workpiece and suppression of occurrence of wrinkles.

  The present invention has been made in order to solve the above-described problems, and provides a press molding method and a press molding apparatus capable of achieving both suppression of work cracking and suppression of wrinkle generation. To do.

According to one aspect of the present invention, the press molding method comprises:
A press molding method in which a workpiece is press-molded with a press die composed of an upper die and a lower die while holding the workpiece with a die cushion,
A press that lowers the press position step by step while pressing and releasing the work by the press die a plurality of times until the press position at which the work is pressed by the press die reaches the bottom dead center of the press. With a process,
In the pressing step, the pressing force for pressing the workpiece by the die cushion is controlled separately from the pressing force for pressing the workpiece by the press die.

According to one aspect of the present invention, a press molding apparatus comprises:
A press mold apparatus comprising a press mold composed of an upper mold and a lower mold, and a die cushion, and press-molding the work with the press mold while pressing the work with the die cushion,
A pressing process in which the press position is lowered step by step while pressing and releasing the work by the press mold a plurality of times until the press position at which the work is pressed by the press mold reaches the bottom dead center. Run
The press molding apparatus includes:
In the pressing step, a first control unit that controls a press forming force for press forming a workpiece by the press die;
A second control unit that controls, in addition to the press-forming force controlled by the first control unit, a pressing force for pressing the workpiece by the die cushion in the pressing step;

  According to the aspect mentioned above, the effect that the press molding method and press molding apparatus which can aim at coexistence with suppression of generation | occurrence | production of a crack of a workpiece | work and suppression of generation | occurrence | production of a wrinkle can be provided.

1 is a diagram illustrating a configuration example of a press forming apparatus according to Embodiment 1. FIG. It is a figure which shows an example of the press molding method which concerns on related technology. 3 is a diagram showing an example of a press molding method according to Embodiment 1. FIG. It is a figure which shows an example of how the lower surface of an upper mold | die in the middle of shaping | molding, and a wrinkle pressing surface move in the press molding method which concerns on Embodiment 1. It is a figure which shows an example of the stress-strain diagram estimated about the metal plate in the middle of shaping | molding with the press molding method which concerns on Embodiment 1. FIG. It is a figure which shows the example of 1 structure of the press molding apparatus which concerns on Embodiment 2. FIG. FIG. 6 is a diagram illustrating a configuration example of a press forming apparatus according to a third embodiment.

Embodiments of the present invention will be described below with reference to the drawings. In the drawings described below, the same or corresponding elements are denoted by the same reference numerals, and redundant description is omitted as necessary for the sake of clarity.
(1) Embodiment 1
First, with reference to FIG. 1, the structure of the press molding apparatus 1 which concerns on this Embodiment 1 is demonstrated. FIG. 1 is a diagram illustrating a configuration example of the press molding apparatus 1 according to the first embodiment.
As shown in FIG. 1, the press molding apparatus 1 according to the first embodiment includes an upper mold 10, a lower mold 20, a slide 30, a die cushion device 40, a slide motion controller 50, a cushion motion controller 60, and synchronous control. Part 70 is provided.

  The upper mold 10 has a convex portion formed on the central lower surface side, and the lower mold 20 has a concave portion corresponding to the convex portion of the upper mold 10 formed on the central upper surface side. The upper mold 10 and the lower mold 20 are arranged vertically so that the convex part of the upper mold 10 and the concave part of the lower mold 20 face each other, and press-molded into a hat mold with a metal plate W serving as a work sandwiched in the vertical direction. (Drawing), which constitutes a press die.

  The upper mold 10 is fixed to the lower surface of the slide 30 and is driven by a servo motor or a hydraulic servo (not shown) to move up and down. Therefore, the upper die 10 moves up and down together with the slide 30 while being fixed to the lower surface of the slide 30. The position of the lower mold 20 is fixed. When the slide 30 is lowered, a press forming force for pressing the metal plate W in the vertical direction by the upper mold 10 and the lower mold 20 is generated.

  The die cushion device 40 is provided for the purpose of suppressing generation of wrinkles in the metal plate W during press forming of the metal plate W, and is a die that is driven by a servo motor (not shown) or a hydraulic servo to perform a lifting operation. A cushion body 41 is provided. The die cushion body 41 is disposed below the lower mold 20, and the die cushion device 40 includes a die cushion 42 that extends upward from the upper surface of the die cushion body 41 and is disposed along the outer wall of the lower mold 20. ing. The concave portion of the lower mold 20 penetrates up and down, and the die cushion device 40 includes a die cushion 43 that extends upward from the upper surface of the die cushion main body 41 and is inserted into the concave portion of the lower mold 20. Yes. When the die cushion main body 41 rises, a pressing force (hereinafter referred to as a wrinkle pressing force) is generated by the die cushions 42 and 43 so as to sandwich and hold the metal plate W between the upper die 10 in the vertical direction.

  During press molding of the metal plate W, the die cushions 42 and 43 generate wrinkle pressing force to hold the metal plate W, while the upper die 10 and the lower die 20 generate press molding force to press the metal plate W. I do.

  The slide motion controller 50 is a first control unit that controls the lifting / lowering operation of the slide 30 (upper mold 10). When the slide 30 (upper die 10) moves up and down, the position of the lower surface of the upper die 10 changes, and the press forming force on the metal plate W changes. Therefore, it is possible to control the press forming force on the metal plate W by controlling the lifting / lowering operation of the slide 30 (upper die 10).

  The cushion motion controller 60 is a second control unit that controls the lifting and lowering operation of the die cushion main body 41. When the die cushion body 41 moves up and down, the positions of the upper surfaces of the die cushions 42 and 43 (that is, the position of the wrinkle pressing surface) change, and the wrinkle pressing force against the metal plate W changes. Therefore, the wrinkle pressing force on the metal plate W can be controlled by controlling the lifting and lowering operation of the die cushion main body 41.

  The synchronization control unit 70 controls the timing of the lifting / lowering operation of the die cushion main body 41 controlled by the cushion motion controller 60 to be synchronized with the timing of the lifting / lowering operation of the slide 30 (upper mold 10) controlled by the slide motion controller 50. For example, the synchronization control unit 70 performs synchronization control such as starting the lowering of the die cushion body 41 at the timing when the slide 30 (upper mold 10) starts to lower.

  Thus, in the first embodiment, the control of the press forming force by the upper mold 10 and the lower mold 20 performed by the slide motion controller 50 and the wrinkle pressing force by the die cushions 42 and 43 performed by the cushion motion controller 60 are performed. Control is performed separately. However, the timing of control of both is synchronized by the synchronization control unit 70 as described above.

  Subsequently, the press molding method according to the first embodiment will be described in comparison with the press molding method according to the related art.

Initially, with reference to FIG. 2, the press molding method which concerns on related technology is demonstrated. FIG. 2 is a diagram illustrating an example of a press forming method according to the related art.
As shown in FIG. 2, the upper die 10 is lowered from the initial position, and a press forming force is generated by the upper die 10 and the lower die 20 to press the metal plate W (process P91, P92, P93). At this time, the die cushions 42 and 43 are raised from the initial position, and a wrinkle pressing force is generated by the die cushions 42 and 43 to press the metal plate W. In this manner, the metal plate W is pressed by the upper die 10 and the lower die 20 while the metal plate W is pressed by the die cushions 42 and 43. Thereafter, the upper die 10 is further lowered to reach the press bottom dead center at the press position where the metal plate W is pressed (process P94).

  Here, the metal plate W is always pressed by the upper mold 10 and the lower mold 20 after the process P92. For this reason, the amount of inflow of the material of the metal plate W into the vertical wall portion of the concave portion of the lower mold 20 is insufficient, and the metal plate W may be cracked at the vertical wall portion.

Next, the press molding method according to the first embodiment will be described with reference to FIG. FIG. 3 is a diagram illustrating an example of the press molding method according to the first embodiment.
As shown in FIG. 3, the first processes P1 to P3 are the same as the processes P91 to P93 according to the related art.

  However, in the subsequent process P4, the upper mold 10 is raised. Thereby, the metal plate W will be in the state by which the press by the upper mold | type 10 and the lower mold | type 20 was released, and the material of the metal plate W will flow into a vertical wall part. Therefore, it can suppress that a crack generate | occur | produces in the metal plate W in a vertical wall part.

  In the subsequent process P5, the upper mold 10 is lowered again. As a result, the metal plate W is pressed by the upper mold 10 and the lower mold 20. At this time, the press position of the metal plate W is lower than the press position when the upper die 10 was lowered last time.

  Thereafter, the processes P4 and P5 are repeated until the press position of the metal plate W reaches the press bottom dead center (process P6).

  As described above, in the first embodiment, while pressing and releasing the metal plate W by the upper die 10 and the lower die 20, the press position of the metal plate W is lowered stepwise to the press bottom dead center. Go. When the upper mold 10 is lowered, the amount of inflow of the material of the metal plate W into the vertical wall portion of the lower mold 20 is insufficient, and the metal plate W may be cracked at the vertical wall portion. However, in the first embodiment, before the crack is generated due to the lowering of the upper die 10, the upper die 10 is raised and the material of the metal plate W is caused to flow into the vertical wall portion of the lower die 20. Thereby, it can suppress that a crack generate | occur | produces in the metal plate W in a vertical wall part.

  In the first embodiment, the control of the wrinkle pressing force by the die cushions 42 and 43 is performed separately from the control of the press forming force by the upper die 10 and the lower die 20. Therefore, for example, the wrinkle of the metal plate W hardly occurs, but in a situation where cracks are likely to occur, the wrinkle holding force is reduced, and the amount of inflow of the metal plate W material into the vertical wall portion of the lower mold 20 is increased. be able to. Thereby, generation | occurrence | production of the crack of the metal plate W can further be suppressed. Conversely, cracking of the metal plate W is unlikely to occur, but in a situation where wrinkles are likely to occur, generation of wrinkles of the metal plate W can be suppressed by increasing the wrinkle holding force. Therefore, it is possible to achieve both suppression of cracking of the metal plate W and suppression of generation of wrinkles.

  Next, referring to FIG. 4, a method for controlling the wrinkle pressing force by the die cushions 42 and 43 and the press forming force by the upper mold 10 and the lower mold 20 will be specifically described. FIG. 4 is a diagram illustrating an example of how the lower surface of the upper mold 10 and the wrinkle pressing surfaces (upper surfaces of the die cushions 42 and 43) move during the formation of the metal plate W by the press forming method according to the first embodiment. In FIG. 4, the horizontal axis represents time [second], and the vertical axis represents stroke [mm] indicating the distance from the press bottom dead center. FIG. 4 shows a situation where the processes P4 and P5 of FIG. 3 are repeatedly performed.

  First, with reference to FIG. 4, the control method of the press molding force by the upper mold | type 10 and the lower mold | type 20 is demonstrated. As shown in FIG. 4, the upper mold 10 is raised by T1 [mm] in the process P4 and lowered by T2 (T2> T1) [mm] in the process P5. Therefore, when the processes P4 and P5 are performed once, the upper mold 10 is lowered by T2-T1 [mm]. By repeating these processes P4 and P5 a plurality of times, the upper die 10 is lowered stepwise, and as a result, the press position of the metal plate W is also lowered stepwise, so that the metal plate W is formed stepwise. .

  As described above, when the upper mold 10 is lowered, the amount of inflow flowing into the vertical wall portion of the lower mold 20 of the material of the metal plate W is insufficient, and the metal plate W may be cracked at the vertical wall portion. . However, in the first embodiment, before the crack occurs in the metal plate W, in the process P4, the upper mold 10 is raised, and the material of the metal plate W is caused to flow into the vertical wall portion of the lower mold 20, Thereafter, the upper mold 10 is lowered again in the process P5. Thereby, it can suppress that a crack generate | occur | produces in the metal plate W in the vertical wall part of the lower mold | type 20. FIG. In addition, the effect which suppresses generation | occurrence | production of a crack improves, so that the shaping | molding amount (equivalent to T2-T1) of the metal plate W is made finer.

  Further, since the metal plate W is formed stepwise, the forming load by the upper mold 10 can also be reduced. In addition, since the metal plate W is formed step by step, the metal plate W can suppress the occurrence of springback in the portion formed near the shoulder portion of the lower mold 20, thereby improving accuracy freezeability. be able to.

  Next, with reference to FIG. 5, the principle by which the press molding method according to the first embodiment can suppress the occurrence of cracks will be described. FIG. 5 is a diagram showing an example of a stress strain diagram estimated for the metal plate W being formed by the press forming method according to the first embodiment. In FIG. 5, the horizontal axis represents the strain ε, and the vertical axis represents the stress σ. Further, X1 and X2 shown in FIG. 5 respectively represent the state of the metal plate W at X1 and X2 in FIG.

  As shown in FIG. 5, when the upper die 10 is raised in the process P4 when the state of the metal plate W is X1, the stress of the vertical wall portion of the lower die 20 is reduced in the metal plate W, and the vertical die Since the wall portion shrinks by the amount of elastic deformation, the material of the metal plate W flows into the vertical wall portion. Subsequently, in the process P5, when the upper die 10 is lowered, the stress of the vertical wall portion of the lower die 20 increases in the metal plate W, so that the portion of the vertical wall portion extends by the amount of elastic deformation, and the original X1 It plasticizes to the state of X2 where the strain has advanced from the state. In this way, each time the processes P4 and P5 are repeated, the metal plate W flows into the vertical wall portion of the lower mold 20 and the strain progresses.

  Next, with reference to FIG. 4, the control method of the wrinkle pressing force by the die cushions 42 and 43 will be described. In the first embodiment, the control of the wrinkle pressing force by the die cushions 42 and 43 is performed separately from the control of the press forming force by the upper die 10 and the lower die 20. In FIG. 4, two patterns 1 and 2 are shown as a method of controlling the wrinkle pressing force by the die cushions 42 and 43.

  As shown in FIG. 4, the pattern 1 is a pattern in which the metal plate W is always pressed by the die cushions 42 and 43 while the processes P4 and P5 are repeated. Specifically, the same movement as the lower surface of the upper mold 10 is performed so that the distance between the wrinkle pressing surface and the lower surface of the upper mold 10 is always constant, that is, the wrinkle pressing force is always constant and increased. , Moving the wrinkle holding surface. For example, the pattern 1 is a pattern that is used in a situation in which cracking of the metal plate W hardly occurs but wrinkles are likely to occur, and the generation of wrinkles of the metal plate W is suppressed by increasing the wrinkle pressing force. be able to.

  On the other hand, the pattern 2 has a state in which the metal plate W is pressed by the die cushions 42 and 43 and a state in which the press by the die cushions 42 and 43 is released while the processes P4 and P5 are repeated. It is a repeated pattern. Specifically, in the process P5, at the timing when the lowering of the upper mold 10 is completed, the distance between the wrinkle pressing surface and the lower surface of the upper mold 10 is lengthened, and the wrinkle pressing force is reduced, thereby reducing the die cushion. The pressing of the metal plate W by 42 and 43 is released. Here, in the process P5, while the upper mold 10 is being lowered, the distance between the wrinkle pressing surface and the lower surface of the upper mold 10 is shortened to increase the wrinkle pressing force. The metal plate W is pressed again by 42 and 43. However, the pattern 2 is not limited to this, and may be a pattern that always reduces the wrinkle pressing force. The pattern 2 is, for example, a pattern that is used in a situation where wrinkles of the metal plate W are unlikely to occur but are likely to be cracked. By reducing the wrinkle holding force, the material of the metal plate W is reduced to that of the lower mold 20. It can be made to flow into a vertical wall part and generation | occurrence | production of the crack of the metal plate W can be suppressed.

  As described above, in the first embodiment, the control of the wrinkle pressing force by the die cushions 42 and 43 is performed separately from the control of the press forming force by the upper mold 10 and the lower mold 20. Therefore, as a method for controlling the wrinkle holding force, for example, cracking of the metal plate W is unlikely to occur, but in the situation where wrinkles are likely to occur, the pattern 1 is used, and the wrinkle of the metal plate W is not likely to occur, but It is also possible to use pattern 2 in situations where it is easy to do. Therefore, it is possible to achieve both suppression of cracking of the metal plate W and suppression of generation of wrinkles.

  In the pattern 2, the state in which the pressing of the metal plate W by the die cushions 42 and 43 is released is a predetermined number of times of the release performed a plurality of times, so that the metal plate W is the upper mold 10 and the die cushions 42 and 43. The metal plate W may be in a state where it is in contact with both, and the remaining number of times may be a state where the metal plate W is separated from at least one of the upper mold 10 and the die cushions 42 and 43. These two states can be changed to either state by adjusting the distance between the wrinkle pressing surface and the lower surface of the upper mold 10, that is, the wrinkle pressing force, for example. For example, in a situation where wrinkles of the metal plate W are unlikely to occur but cracks are likely to occur, the metal plate W is controlled to be separated from at least one of the upper mold 10 and the die cushions 42 and 43 to suppress wrinkle. It can also be omitted. Further, in a situation where wrinkles of the metal plate W are likely to occur and cracks are also likely to occur, the metal plate W is controlled to be in contact with both the upper mold 10 and the die cushions 42 and 43, and a small wrinkle presser is controlled. It can wrinkle with force. Thereby, coexistence with the suppression of generation | occurrence | production of the crack of the metal plate W and suppression of generation | occurrence | production of a wrinkle can be aimed at with still higher precision.

(2) Embodiment 2
With reference to FIG. 6, the structure of the press molding apparatus 2 which concerns on this Embodiment 2 is demonstrated. FIG. 6 is a diagram illustrating a configuration example of the press molding apparatus 2 according to the second embodiment.
As shown in FIG. 6, the press molding apparatus 2 according to the second embodiment is different from the press molding apparatus 1 according to the first embodiment in that a state monitoring controller 80 is added. The other configuration of the second embodiment is the same as that of the first embodiment.

  The state monitoring controller 80 is connected to the equipment state of the press molding apparatus 2 (for example, temperature, molding load by the upper mold 10), the material state of the metal plate W (for example, the material of the metal plate W to the vertical wall portion of the lower mold 20). Inflow amount) or at least one state of the upper die 10 and the lower die 20 (for example, the wear amount of the upper die 10 and the lower die 20, the number of shots of the upper die 10).

  For example, regarding the equipment state, the temperature can be monitored using a temperature sensor or the like, and the load of the upper mold 10 can be monitored using a load sensor or the like attached to the slide 30 or the like. Further, regarding the material state, the inflow amount of the material of the metal plate W can be monitored by detecting the displacement of the metal plate W with a laser displacement meter. Regarding the mold state, the wear amount of the upper mold 10 and the lower mold 20 can be monitored by detecting the distance of the gap between the upper mold 10 and the lower mold 20, and the number of shots of the upper mold 10 is It can be monitored by measuring the number of times the upper mold 10 is moved up and down.

  In the second embodiment, the slide motion controller 50 includes at least the equipment state of the press forming apparatus 2 monitored by the state monitoring controller 80, the material state of the metal plate W, or the mold states of the upper mold 10 and the lower mold 20. Based on one state, the raising / lowering operation of the slide 30 (upper mold | type 10), ie, the press molding force with respect to the metal plate W, is controlled.

  For example, when the slide motion controller 50 determines that the amount of inflow of the material of the metal plate W into the vertical wall portion of the lower mold 20 is large based on the material state of the metal plate W, the press forming force is increased. To control. Thereby, since the frequency | count of raising / lowering of the upper mold | type 10 can be reduced, the improvement of productivity can be aimed at. Further, when the slide motion controller 50 determines that the amount of inflow of the material of the metal plate W into the vertical wall portion of the lower mold 20 is small, the slide motion controller 50 controls the press forming force to be small. Thereby, since the stress of the metal plate W in the vertical wall part of the lower mold | type 20 can be relieved, generation | occurrence | production of the crack of the metal plate W in a vertical wall part can be suppressed.

  The slide motion controller 50 controls the press molding force to be increased when it is determined that the molding load by the upper mold 10 is small based on the equipment state of the press molding apparatus 2. Thereby, since the frequency | count of raising / lowering of the upper mold | type 10 can be reduced, the improvement of productivity can be aimed at. Further, when the slide motion controller 50 determines that the molding load by the upper mold 10 is large, the slide motion controller 50 controls the press molding force to be small. Thereby, since the stress of the metal plate W in the vertical wall part of the lower mold | type 20 can be relieved, generation | occurrence | production of the crack of the metal plate W in a vertical wall part can be suppressed.

(3) Embodiment 3
With reference to FIG. 7, the structure of the press molding apparatus 3 which concerns on this Embodiment 3 is demonstrated. FIG. 7 is a diagram illustrating a configuration example of the press molding apparatus 3 according to the third embodiment.
As shown in FIG. 7, the press molding apparatus 3 according to the third embodiment is different from the press molding apparatus 1 according to the first embodiment in that the upper mold 11 and the lower mold 20 are replaced by the upper mold 11 and the lower mold 20. The difference is that the lower mold 21 is provided, the die cushions 44 and 45 are provided instead of the die cushions 42 and 43, the members 46 and 47, the actuator controller 90, and the actuators 91 to 95 are added. The other configuration of the third embodiment is the same as that of the first embodiment.

  The upper mold 11 and the lower mold 21 are implemented in that the convex part is formed on the central upper surface side of the lower mold 21 and the concave part corresponding to the convex part of the lower mold 21 is formed on the central lower surface side of the upper mold 11. This is different from the upper mold 10 and the lower mold 20 according to the first embodiment.

  The die cushions 44 and 45 are different from the die cushions 42 and 43 according to the first embodiment in that they are provided on the upper mold 11 side. In the third embodiment, the members 46 and 47 provided on the lower mold 21 side move up and down as the die cushion main body 41 moves up and down. The die cushion 44 holds and presses the metal plate W between the lower mold 21 in the vertical direction, and the die cushion 45 presses and holds the metal plate W between the members 47 in the vertical direction. In the third embodiment, the lower mold 21 also moves up and down as the die cushion body 41 moves up and down.

  The actuator 91 is an actuator that is disposed inside the upper mold 11 and changes the mold shape of the upper mold 11 in a direction that expands or contracts in the left-right direction in the drawing. The actuator 92 is an actuator that is disposed outside the upper mold 11 and changes the mold shape of the upper mold 11 in a direction that expands or contracts in the left-right direction in the drawing.

  The actuator 93 is an actuator that is disposed inside the lower mold 21 and changes the mold shape of the lower mold 21 in a direction that expands or contracts in the left-right direction in the drawing. The actuator 94 is an actuator that is disposed outside the lower mold 21 and changes the mold shape of the lower mold 21 in a direction that expands or contracts in the left-right direction in the drawing.

  The actuator controller 90 determines the press position of the metal plate W based on the lifting / lowering operation of the slide 30 (upper mold 10) controlled by the slide motion controller 50, and the actuators 91 to 95 based on the press position of the metal plate W. To control.

  For example, the slide motion controller 50 includes the actuators 91, 91 so that the mold shape of the upper mold 11 and the mold shape of the lower mold 21 are reduced in the horizontal direction in the drawing as the press position of the metal plate W is lowered stepwise. 92, 93 and 94 are controlled.

  As described above, in the third embodiment, not only the wrinkle pressing force by the die cushions 44 and 45 is controlled based on the lifting / lowering operation of the slide 30 (upper mold 10), but the shape of the upper mold 11 and The mold shape of the lower mold 21 can be controlled.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention. For example, although the second and third embodiments have been described separately, a configuration in which the second and third embodiments are combined may be employed.

1, 2, 3 Press molding device 10, 11 Upper die 20, 21 Lower die 30 Slide 40 Die cushion device 41 Die cushion main body 42, 43, 44, 45 Die cushion 46, 47 Member 50 Slide motion controller 60 Cushion motion controller 70 Synchronous control unit 80 Status monitoring controller 90 Actuator controller 91, 92, 93, 94 Actuator

Claims (6)

A press molding method in which a workpiece is press-molded with a press die composed of an upper die and a lower die while holding the workpiece with a die cushion,
A press that lowers the press position step by step while pressing and releasing the work by the press die a plurality of times until the press position at which the work is pressed by the press die reaches the bottom dead center of the press. With a process,
In the pressing step, the pressing force for pressing the workpiece by the die cushion is controlled separately from the pressing force for pressing the workpiece by the press die.   The press molding method according to claim 1, wherein in the pressing step, pressing and releasing of the workpiece by the die cushion are repeated a plurality of times.   The state in which the workpiece is released by the die cushion is a state in which the workpiece is in contact with both the press die and the die cushion, and the remaining number of times the workpiece is pressed. The press molding method according to claim 2, wherein the press molding method is in a state of being separated from at least one of a mold and the die cushion. In the pressing step,
Monitoring at least one of the equipment state of the press molding device, the material state of the workpiece, or the die state of the press die;
4. The press forming force according to claim 1, wherein the press forming force is controlled based on at least one state of an equipment state of a press forming device, a material state of a workpiece, or a die state of the press die. 5. Press molding method.   5. The press molding method according to claim 1, wherein, in the pressing step, the mold shape of the upper mold and the mold shape of the lower mold are changed based on the press position. 6. A press mold apparatus comprising a press mold composed of an upper mold and a lower mold, and a die cushion, and press-molding the work with the press mold while pressing the work with the die cushion,
A pressing process in which the press position is lowered step by step while pressing and releasing the work by the press mold a plurality of times until the press position at which the work is pressed by the press mold reaches the bottom dead center. Run
The press molding apparatus includes:
In the pressing step, a first control unit that controls a press forming force for press forming a workpiece by the press die;
A press forming apparatus comprising: a second control unit that controls a pressing force for pressing the work by the die cushion in addition to the press forming force controlled by the first control unit in the pressing step.

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