Pressing apparatus and method for manufacturing pressed products

Abstract

To provide a press working apparatus and a method for manufacturing press-worked products that can suppress the complexity of the press working apparatus. [Solution] The press working apparatus according to the present disclosure is a press working apparatus that punches out a sequentially fed sheet material using an upper die equipped with a stripper and a lower die equipped with a die, wherein the die comprises a fixed part and a movable part that can be lowered, and the movable part lowers for a predetermined period that overlaps with the period during which the stripper rises.

Description

Technical Field

[0001] The present disclosure relates to a press working apparatus and a method for manufacturing a press worked product.

Background Art

[0002] In recent years, in a processing apparatus for press working a sheet material (work) while feeding it forward, a technique for suppressing the vibration of the sheet material during forward feeding has been disclosed. For example, the press working apparatus disclosed in Patent Document 1 has a pressing member on the upper die of the apparatus. The pressing member presses the electromagnetic steel sheet from above until the electromagnetic steel sheet is lifted to a predetermined upper position by a lifter or the like. Thereby, when lifting the electromagnetic steel sheet to a predetermined upper position, it is possible to suppress the electromagnetic steel sheet from vibrating upward due to the inertial force generated in the upward direction of the electromagnetic steel sheet.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The press working apparatus of Patent Document 1 includes a pressing member on the upper die of the apparatus in order to suppress the vibration of the sheet material. On the other hand, a lifter for preventing interference between the electromagnetic steel sheet and the lower die is provided on the lower die of the press working apparatus of Patent Document 1. Further, a guide for restricting the displacement of the electromagnetic steel sheet in the width direction of the electromagnetic steel sheet is provided on the lower die of the press working apparatus. Thus, in the press working apparatus of Patent Document 1, devices for suppressing the vibration and displacement of the electromagnetic steel sheet are dispersedly provided on the upper die and the lower die. As a result, there is a possibility that the press working apparatus for suppressing vibration becomes complicated.

[0005] This disclosure is made to solve these problems and aims to provide a press working apparatus and a method for manufacturing press-worked products that can suppress the complexity of the press working apparatus. [Means for solving the problem]

[0006] The press working apparatus according to this disclosure is a press working apparatus that punches out a sequentially fed sheet material using an upper die equipped with a stripper and a lower die equipped with a die, wherein the die comprises a fixed part and a movable part that can descend, and the movable part descends for a predetermined period that overlaps with the period during which the stripper rises. As a result, the movable part can generate a downward inertial force and a downward airflow on the sheet material. Since this is a downward force that counteracts the upward force generated on the sheet material due to the rise of the stripper, the movable part can suppress the upward movement of the sheet material. Furthermore, by concentrating all the devices that suppress fluttering and displacement of the sheet material in the lower die, the design of the press working apparatus can be simplified and the complexity of the press working apparatus can be suppressed.

[0007] The manufacturing method for press-formed products according to this disclosure is a manufacturing method for press-formed products using an upper die equipped with a stripper and a lower die equipped with a die, wherein a progressively fed sheet material is used to manufacture a press-formed product, comprising the steps of punching out the sheet material with the upper die and the lower die, and the step of the movable part of the die descending for a predetermined period that overlaps with the period during which the stripper rises. When manufacturing a press-formed product, the movable part of the die generates a downward inertial force and a downward airflow on the sheet material. This is a downward force that counteracts the upward force generated on the sheet material due to the rise of the stripper, and thus the press-formed product can be manufactured using a manufacturing method that suppresses the upward movement of the sheet material. Furthermore, with such a manufacturing method for press-formed products, all devices that suppress fluttering and misalignment of the sheet material can be concentrated in the lower die of the press-formed device, thereby simplifying the design of the press-formed device and suppressing the complexity of the press-formed device. [Effects of the Invention]

[0008] According to this disclosure, it is possible to provide a press working apparatus and a method for manufacturing press-worked products that can suppress the complexity of the press working apparatus. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic diagram of the press working apparatus 1 according to this disclosure. [Figure 2] Figure 2 is a schematic diagram showing how punch 22 punches out sheet metal WW. [Figure 3] Figure 3 is a schematic diagram of the sheet metal WW inside the press working machine 1, viewed from a vertically upward direction. [Figure 4] Figure 4 is a schematic diagram relating to the rising phenomenon of the plate material WW. [Figure 5] Figure 5 is a schematic diagram showing the state when fluttering occurs in the sheet material. [Modes for carrying out the invention]

[0010] Embodiments of the present disclosure will be described below with reference to the drawings. Figure 1 is a schematic diagram of a press working apparatus 1 according to the present disclosure. The press working apparatus 1 performs a punching process, which is a type of press working, on a sheet material WW. The sheet material WW is a strip-shaped thin sheet material made of metal such as steel or aluminum. The sheet material WW may be, for example, an electrical steel sheet.

[0011] In this disclosure, the press working apparatus 1 performs progressive press working on a sheet material WW. Progressive press working is a processing method in which multiple processes are arranged in a predetermined direction at predetermined intervals on a single progressive die. In other words, the press working apparatus 1 according to this disclosure performs press working on the sheet material WW multiple times. Here, the progressive press working according to this disclosure may be double-row or single-row. That is, the progressive die according to this disclosure may or may not be formed to perform punching in multiple rows simultaneously.

[0012] Furthermore, in this disclosure, the press working apparatus 1 manufactures press-formed products. Here, a press-formed product refers to any processed product manufactured by the press working apparatus 1 performing progressive press working on a sheet material WW. That is, a press-formed product may be a sheet material punched out by the press working apparatus 1. Hereafter, the sheet material WW punched out by the press working apparatus 1 will be referred to as punched sheet material WO. In other words, a press-formed product may be punched sheet material WO. Also, a press-formed product may be the sheet material WW remaining after punching by the press working apparatus 1. In other words, a press-formed product may be a part other than punched sheet material WO.

[0013] Upstream of the press working apparatus 1, an uncoiler, a leveler, and a feeder (none of which are shown) may be arranged. The uncoiler holds the rolled sheet material WW in a pullable manner. The uncoiler has the function of unwinding the sheet material WW by rotating it when it is fed to the press working apparatus 1. The leveler is located downstream of the uncoiler. The leveler has a pair of straightening rollers and corrects the deflection that occurs in the sheet material WW unwound from the uncoiler. The feeder is located further downstream of the leveler. The feeder has a pair of feed rollers and, by the rotation of these rollers, conveys the sheet material WW straightened by the leveler to the press working apparatus 1.

[0014] The press working apparatus 1 comprises an upper die 2 and a lower die 3. The upper die 2 and the lower die 3 are formed such that multiple processes are arranged in a predetermined direction at predetermined intervals. The upper die 2 and the lower die 3 are a pair of dies that punch out sheet metal WW by applying pressure to it. Here, the upper die 2 and the lower die 3 together are also referred to as progressive dies.

[0015] The upper die 2 and lower die 3 may or may not be positioned opposite each other in the vertical direction. That is, the upper die 2 and lower die 3 may or may not be positioned so that the sheet metal WW is conveyed and pressed in the horizontal direction. Hereafter, the upper die 2 and lower die 3 will be assumed to be positioned opposite each other in the vertical direction. Also, hereafter, the direction in which the sheet metal WW is conveyed will be referred to as the forward direction. The forward direction of the sheet metal WW will also be referred to as the direction of travel of the sheet metal WW. In Figure 1, the upper die 2 and lower die 3 are positioned opposite each other in the Z-axis direction (vertical direction), and the sheet metal WW is conveyed in the positive X-axis direction (horizontal direction) by, for example, a feed device. That is, in Figure 1, the forward direction of the sheet metal WW is the positive X-axis direction.

[0016] The upper die 2 is a movable die located above the sheet metal WW flowing through the press working apparatus 1. On the other hand, the lower die 3 is a die located below the sheet metal WW flowing through the press working apparatus 1. The upper die 2 can move, for example, in the vertical direction. That is, the upper die 2 can descend to approach the lower die 3, and can also rise away from the lower die 3. This movement of the upper die 2 can be achieved by a press machine (not shown).

[0017] The upper die 2 comprises a stripper 21, a punch 22, and a punch hole 23. The stripper 21 descends in the direction of the lower die 3 during punching. The lower surface of the descended stripper 21 and the surface of the lower die 3 facing the lower surface grip the sheet metal WW as the punch 22 rises after punching. In this way, the stripper 21 removes the sheet metal WW that has become stuck to the rising punch 22 from the punch 22. The stripper 21 is typically a substantially rectangular sheet metal member. The stripper 21 may achieve its upward and downward movement by being connected to a punch holder (not shown) that holds the punch 22 via an elastic body (not shown) on its upper surface.

[0018] The punch 22 is part of the processing section when punching the sheet material WW. The punch 22 is typically a columnar body whose horizontal cross-section has an arbitrary shape. The punch 22 punches the sheet material WW according to the shape of the contour of its horizontal cross-section to produce the punched sheet material WO. The punch 22 is formed with a dimension slightly smaller than the through-hole disposed in the lower die 3. Thereby, when the punch 22 is inserted into the through-hole, the punch 22 can ensure a certain clearance with the through-hole.

[0019] The upper surface of the punch 22 may be held by a punch holder. Also, the upper surface of the punch holder may be joined to a press machine. Due to the vertical movement of the punch holder accompanying the vertical movement by the press machine, the punch 22 may realize its vertical movement.

[0020] The punch hole 23 is part of the processing section when punching the sheet material WW. Specifically, the punch hole 23 is the through-hole of the stripper 21 provided in the corresponding punch 22. The punch hole 23 has a shape corresponding to the punch 22 passing through the punch hole 23, and its central axis extends in the vertical direction.

[0021] The lower die 3 includes a die 31, a die hole 32, a lifter 33, and a side guide 34. The die 31 includes a fixed portion 311, a movable portion 312, and a holding portion 313. The die 31 is formed to sandwich the sheet material WW together with the stripper 21 during the punching process by the punch 22.

[0022] The fixed portion 311 is the non-moving part of the die 31. In other words, the fixed portion 311 is the non-descending part of the die �. Further in other words, the fixed portion 311 is the part designed not to be able to descend. Specifically, the fixed portion 311 is the non-descending part when the stripper 21 and the punch 22 ascend.

[0023] The fixing portion 311 may be located elsewhere than the periphery of the die hole 32. Furthermore, the fixing portion 311 may be located around the holding portion 313 and the side guide 34. Additionally, the fixing portion 311 may be the support portion for the holding portion 313 and the side guide 34 of the die 31.

[0024] The movable part 312 is a movable portion of the die 31. For example, the movable part 312 is a portion of the die 31 that can be moved downwards. In other words, the movable part 312 is a portion of the die 31 that can move away from the plate material WW.

[0025] The movable part 312 may be designed to descend for a predetermined period that overlaps with the period during which the stripper 21 rises. For example, the movable part 312 may begin to descend at the same time that the stripper 21 begins to rise. Alternatively, the movable part 312 may begin to descend after a predetermined time has elapsed since the stripper 21 began to rise. Furthermore, the movable part 312 may begin to descend immediately after the stripper 21 and die 31 have removed the sheet metal WW that has bitten into the rising punch 22 from the punch 22. Moreover, the movable part 312 may begin to descend before the stripper 21 begins to rise.

[0026] The movable part 312, together with the fixed part 311 and the stripper 21, grips the sheet metal WW when the punch 22 punches through it. In other words, the movable part 312 moves down and up between the time the punch 22 punches through the sheet metal WW and the time the punch 22 punches through it again.

[0027] The lowered movable part 312 may begin to rise at the same time that the stripper 21 begins to descend. Alternatively, the movable part 312 may begin to rise after a predetermined time has elapsed since the stripper 21 began to descend. Furthermore, the movable part 312 may begin to rise when the stripper 21 is at rest at its top dead center. Moreover, the movable part 312 may begin to rise while the stripper 21 is rising. In other words, the movable part 312 may complete its lowering and rising operations at the same time that the stripper 21 is rising.

[0028] The movable part 312 may be designed to descend for a predetermined period that overlaps with the period during which the lifter 33 rises. For example, the movable part 312 may begin to descend at the same time that the lifter 33 begins to rise. Alternatively, the movable part 312 may begin to descend after a predetermined time has elapsed since the lifter 33 began to rise. Furthermore, the movable part 312 may begin to descend before the lifter 33 begins to rise.

[0029] The lowered movable part 312 may begin to rise at the same time that the lifter 33 begins to descend. Alternatively, the movable part 312 may begin to rise after a predetermined time has elapsed since the lifter 33 began to descend. Furthermore, the movable part 312 may begin to rise when the lifter 33 is at rest at its top dead center. Moreover, the movable part 312 may begin to rise while the lifter 33 is rising. In other words, the movable part 312 may complete its descent and rise operations at the same time that the lifter 33 is rising.

[0030] The movable part 312 is approximately flush with the fixed part 311 at its top dead center. This allows the movable part 312, the fixed part 311, and the stripper 21 to grip the sheet metal WW when the punch 22 punches it out. This state will be explained with reference to the figures. Figure 2 is a schematic diagram of the punch 22 punching out the sheet metal WW. In Figure 2, the movable part 312 is assumed to be at its top dead center. As shown in Figure 2, the movable part 312 is approximately flush with the fixed part 311 at its top dead center. In other words, in Figure 2, the movable part 312 and the fixed part 311 form an XY plane. This allows the movable part 312, the fixed part 311, and the stripper 21 to grip the sheet metal WW when the punch 22 punches it out.

[0031] The stroke of the movable part 312 may be the same as the stroke of the stripper 21, shorter than the stroke of the stripper 21, or longer than the stroke of the stripper 21. Furthermore, the stroke of the movable part 312 may be the same as the stroke of the lifter 33, shorter than the stroke of the lifter 33, or longer than the stroke of the lifter 33. In other words, the bottom dead center of the movable part 312 may be located at any position.

[0032] The movable part 312 can move in the direction away from the plate material WW and in the opposite direction. In other words, the movable part 312 can move down and up in any direction. The movable part 312 may or may not be able to move down and up in the vertical direction. In other words, the movable part 312 may or may not be able to move down in the vertical downward direction, or be able to move up in the vertical upward direction. That is, the movable part 312 may be able to move down and up in a direction that is at an angle to the vertical direction. In Figure 1, the movable part 312 can move down and up in the vertical direction (Z-axis direction).

[0033] The movable part 312 may have its facing surface with respect to the sheet metal WW located at the periphery of the die hole 32. That is, if the movable part 312 is capable of moving vertically downward and upward, the movable part 312 may be located at the periphery of the die hole 32. If the facing surface of the movable part 312 with respect to the sheet metal WW is located at the periphery of the die hole 32, this facing surface may be located only at the periphery of some of the die holes 32. If the press working apparatus 1 is a double-row product press, the facing surface of the movable part 312 with respect to the sheet metal WW may be located only at the periphery of the die hole 32 of the central row. That is, the movable part 312 may be provided at the center of the sheet metal WW in the width direction, i.e., at any point on the central axis in the conveying direction of the sheet metal WW.

[0034] The movable part 312 may be all or part of the die 31 except for the holding part 313, the side guide 34 and their support parts. In other words, the movable part 312 does not have to have its surface facing the plate material WW located at the periphery of the die hole 32. In Figure 1, the movable part 312 has its surface facing the plate material WW located at the periphery of the die hole 32. Also, in Figure 1, since the movable part 312 can move down and up in the vertical direction, the movable part 312 is located at the periphery of the die hole 32.

[0035] Figure 3 is a schematic diagram of the sheet metal WW inside the press working apparatus 1 as viewed from vertically above. In Figure 3, because the press working apparatus 1 is a double-row product cutter, there are multiple punched holes in the width direction of the sheet metal WW, i.e., in the Y-axis direction. In Figure 3, the surface of the movable part 312 facing the sheet metal WW is represented by a dashed line. That is, in Figure 3, the surface of the movable part 312 facing the sheet metal WW is located at the periphery of the die hole 32, i.e., at the periphery of the punched holes in the figure. In particular, in Figure 3, the movable part 312 is provided only for a portion of the punched holes in the central row of the multiple rows of punched holes in the width direction of the sheet metal WW.

[0036] The movable part 312 may be able to move in conjunction with the vertical movement of the upper die 2 by a cam mechanism. Alternatively, the movable part 312 may be able to move independently of the upper die 2. In other words, the press working apparatus 1 may have a multi-axis structure. The movable part 312 may be able to operate by hydraulics or pneumatics.

[0037] A certain clearance may be maintained between the movable part 312 and the fixed part 311. In other words, the movable part 312 may be designed so as not to slide against the fixed part 311 during movement.

[0038] The holding portion 313 has a space for holding the lifter 33. The holding portion 313 has a space such that when the lifter 33 is lowered to its lowest point, the upper end of the lifter 33 and the upper surface of the die 31 are substantially flush. The shape of the holding portion 313 is typically concave, but it may also have a shape that matches the shape of the lifter 33. In Figure 1, the holding portion 313 has a concave shape. In addition, there may be multiple holding portions 313 arranged in the progressive direction of the sheet material WW, or only one may be arranged throughout the process of the press working apparatus 1. When multiple holding portions 313 are arranged, they may be arranged, for example, at regular intervals in the progressive direction of the sheet material WW.

[0039] The die hole 32 is part of the processing area when punching out the sheet metal WW. That is, the die hole 32 is a through hole of the die 31 for punching out the sheet metal WW in a shape that follows the contour of the punch 22. The die hole 32 is positioned perpendicularly to the punch 22 and the punch hole 23. The horizontal cross-section of the die hole 32 has a predetermined shape, such as a circle or a polygon. The central axis of the die hole 32 extends in the vertical direction. The metal piece punched out from the sheet metal WW may be discharged to the outside through the die hole 32. This metal piece is the punched sheet metal WO. That is, this metal piece may or may not be a press-formed product. In Figure 1, the punched sheet metal WO is accumulated in the die hole 32.

[0040] The lifter 33 is a device for releasing and supporting the sheet metal WW punched out by the lower die 3 and the upper die 2 from the lower die 3. The lifter 33 is located within the holding section 313 and is movable vertically within the holding section 313. For example, the lifter 33 rises in conjunction with the upper die 2, which rises when releasing the sheet metal WW from the lower die 3. At this time, the upper end of the lifter 33 pushes up the sheet metal WW, releasing it from the lower die 3. At the highest position of the lifter 33, the upper end of the lifter 33 is in contact with the sheet metal WW. At the lowest position of the lifter 33, the upper end of the lifter 33 and the upper surface of the die 31 are almost flush. Multiple lifters 33 may be arranged in the progressive direction of the sheet metal WW, or only one may be arranged throughout the process of the press working apparatus 1. When multiple lifters 33 are arranged, they may be arranged at regular intervals in the progressive direction of the sheet metal WW.

[0041] The lifter 33 includes a contact portion 331 and an elastic body 332. The upper surface of the contact portion 331 abuts against the lower surface of the sheet material WW when the sheet material WW is punched or when the sheet material WW is fed forward. When the upper surface of the contact portion 331 abuts against the lower surface of the sheet material WW when the sheet material WW is fed forward, the sheet material WW slides along the upper surface of the contact portion 331. The shape of the contact portion 331 can be, for example, cylindrical or prismatic. The contact portion 331 may also have a tapered portion in the forward or reverse direction of the sheet material WW. In Figure 1, the contact portion 331 is columnar and has tapered portions in the forward and reverse directions of the sheet material WW.

[0042] The elastic body 332 is a drive source that raises and lowers the contact portion 331 within the holding portion 313. The elastic body 332 is formed from, for example, a spring, cylinder, urethane, rubber, etc. One end of the elastic body 332 is in contact with or joined to the lower surface of the contact portion 331, and the other end is in contact with or joined to any surface on the inner surface of the holding portion 313. Preferably, the elastic body 332 has a Young's modulus sufficient to push up and support the punched sheet material WW. In Figure 1, the elastic body 332 is formed from a spring. Also in Figure 1, one end of the elastic body 332 is joined to the lower surface of the contact portion 331, and the other end is joined to the lower surface inside the holding portion 313.

[0043] The side guides 34 are configured to suppress misalignment during the transport of the sheet material WW by the feeding device. The side guides 34 are provided on the widthwise edge of the sheet material WW. The side guides 34 may be provided on one edge or on both edges. In addition, multiple side guides 34 may be provided at regular intervals in the forward feeding direction of the sheet material WW. To suppress vertical vibration and widthwise misalignment, the side guides 34 typically have an inverted L-shape and are joined to the lower die 3. Under normal conditions, the side guides 34 may be in close proximity to or in contact with the transported sheet material WW. In Figure 3, multiple side guides 34 are provided on both widthwise edges of the sheet material WW.

[0044] Here, we will explain the effects of providing a movable part 312 to the die 31. First, we will explain the force applied to the sheet metal WW during punching by the press working device 1. When the punch 22 punches out the sheet metal WW with the lower surface of the stripper 21 and the upper surface of the die 31 sandwiching the sheet metal WW, the punch 22 then rises. At that time, the stripper 21 removes the sheet metal WW that has bitten into the punch 22. After that, the stripper 21 rises along with the punch 22. The lifter 33 rises in conjunction with the stripper 21. The sheet metal WW is pushed up by the lifter 33 and rises, and is released from the die 31. Even during this time, the stripper 21 and punch 22 continue to rise. The space created between the sheet metal WW and the stripper 21 is in a low-pressure state immediately after the stripper 21 rises, so air flows in from the surrounding area of ​​the space. This phenomenon is caused by the rising of the stripper 21 and punch 22, resulting in an upward airflow from the lower die 3 to the upper die 2 around the sheet metal WW. Additionally, when the lifter 33 rises and releases the sheet metal WW from the die 31, the lifter 33 lifts the sheet metal WW, creating an upward inertial force on the sheet metal WW.

[0045] If the rigidity of the sheet metal WW is low, the sheet metal WW will rise due to the rising airflow and inertial force. In other words, the sheet metal WW will rise along with the upper die 2. This phenomenon increases the vertical movement of the sheet metal WW, causing it to bend. This phenomenon is more likely to occur, especially downstream of the press working device 1, as products are cut in multiple rows and the sheet metal WW is made thinner. Furthermore, since the rigidity of the periphery of the punched holes in the sheet metal WW is further reduced, this phenomenon is even more likely to occur there.

[0046] Meanwhile, while the upper die 2 is rising, the feeding device transports the sheet metal WW to the next process. If the sheet metal WW does not rise with the upper die 2, it will be fed to the next process while in contact with the lifter 33. The feeding device then stops feeding the material at a predetermined position, and the sheet metal WW is punched out by the next punch 22. However, if the sheet metal WW is fed out by the feeding device while rising with the upper die 2, when the feeding device stops feeding the material, the sheet metal WW will flutter due to gravity causing it to descend and due to inertia. This fluttering of the sheet metal WW can cause feeding problems, such as the sheet metal WW interfering with the edge of the die hole 32 or the lifter 33. In particular, the peripheral edges of the punched holes in the sheet metal WW are more susceptible to the effects of rising air currents than other parts of the sheet metal WW, so they tend to bend upward as the upper die 2 rises and are more prone to bending downward than other parts due to gravity. As a result, the periphery of the punched hole in the plate material WW is particularly prone to interference with the edge of the die hole 32 and the lifter 33.

[0047] This phenomenon will be explained using drawings. Figure 4 is a schematic diagram relating to the rising phenomenon of the sheet material WW. Figure 5 is a schematic diagram when fluttering of the sheet material occurs. Note that the die 31 of the press working apparatus in Figures 4 and 5 does not include a movable part 312 in its configuration. That is, the die 31 of the press working apparatus in Figures 4 and 5 is entirely a fixed part 311 except for the holding part 313. Also, in Figures 4 and 5, elements that are the same as or similar to those in the press working apparatus 1 in Figure 1 are denoted by the same reference numerals.

[0048] After the sheet metal WW is punched out, the lifter 33 rises along with the rise of the stripper 21, pushing up the sheet metal WW. If an updraft occurs at this point, the sheet metal WW will rise along with the rise of the upper die 2, as shown in Figure 4. When the feed device attempts to move the sheet metal WW to the next process while it is rising, the sheet metal WW will flap around as shown in Figure 5 due to gravity causing it to descend and inertia when the feed device stops feeding the material. As a result, the sheet metal WW will interfere with the die hole 32, etc.

[0049] By providing a movable part 312 on the die 31, the fluttering of the sheet metal WW can be suppressed. Specifically, the downward movement of the movable part 312 generates a downward inertial force on the sheet metal WW. In addition, a low-pressure space is created between the sheet metal WW and the downward-moving movable part 312, generating a downward airflow on the sheet metal WW. By downward movement of the movable part 312 for a predetermined period that overlaps with the period during which the stripper 21 rises, a downward force can be applied to the sheet metal WW that counteracts the upward force acting on the sheet metal WW due to the rising of the stripper 21 and lifter 33. As a result, the movable part 312 can suppress the upward movement of the sheet metal WW.

[0050] When the movable part 312 is capable of descending in the vertical direction, the above effect can be obtained for the punched hole in the sheet material WW by providing the movable part 312 on the periphery of the die hole 32. That is, by providing the movable part 312 on the periphery of the die hole 32, a downward inertial force and downward airflow can be generated on the periphery of the punched hole in the sheet material WW. As a result, vertical deflection of the periphery of the punched hole in the sheet material WW can be suppressed.

[0051] Furthermore, by providing a movable part 312 on the die 31, the complexity of the press working apparatus 1 can be suppressed. Specifically, the press working apparatus 1 is equipped with a movable part 312, a lifter 33, and a side guide 34. These are devices for suppressing fluttering and misalignment of the sheet material WW. By concentrating all of these devices in the lower die 3, the design of the press working apparatus 1 can be simplified compared to the case where some of them are provided on the upper die 2, thereby suppressing the complexity of the press working apparatus 1.

[0052] It should be noted that the present invention is not limited to the embodiments described above, and can be modified as appropriate without departing from the spirit of the invention. [Explanation of Symbols]

[0053] 1 Pressing device, 2 Upper die, 3 Lower die, 21 Stripper, 22 Punch, 23 Punch hole, 31 Die, 32 Die hole, 33 Lifter, 34 Side guide, 311 Fixing part, 312 Movable part, 313 Holding part, 331 Contact part, 332 Elastic body, WW Sheet material, WO Punched sheet material

Claims

1. A press working apparatus that punches out sequentially fed sheet material using an upper die equipped with a stripper and a lower die equipped with a die, The die comprises a fixed part and a movable part that can be lowered, The movable part descends during a predetermined period that overlaps with the period during which the stripper rises. Pressing machine.

2. The movable part is capable of descending vertically downwards. The press working apparatus according to claim 1.

3. The lower die further includes a lifter for lifting the plate material when feeding the plate material sequentially. The movable part descends during a predetermined period that overlaps with the period during which the lifter rises. The press working apparatus according to claim 1.

4. The movable part has a surface facing the plate material that is located at the periphery of the die hole in the lower mold. The press working apparatus according to claim 1 or 2.

5. A manufacturing method for producing press-formed products by feeding a sheet metal material sequentially using an upper die equipped with a stripper and a lower die equipped with a die, The steps include punching out the sheet material using the upper die and the lower die, The system includes a step in which the movable part of the die descends during a predetermined period that overlaps with the period in which the stripper rises. A method for manufacturing pressed products.

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