JP2020114606A - Punch structure of press metal mold, press metal mold and manufacturing method of press molding - Google Patents

Abstract

To provide a punch structure which can effectively prevent the occurrence of damage to the punch structure which is repeatedly used for punch processing when manufacturing a press molding including a narrow-width part which is narrow in a width with respect to a thickness, a press metal mold and a manufacturing method of the press molding.SOLUTION: This punch structure 1 which is arranged while protruding from a press metal mold main body in order to punch a press molding including a narrow-width part in which a ratio (w/t) of a width w with respect to a thickness t is 1.5 or lower has a punch tip part 2 having a tip face T including at least narrow-width shapes 3, 4 which correspond to a plane shape of the narrow-width part of the press molding, and a reinforcing rib 6 extending in a protrusion direction of the punch structure 1 is arranged at a part of a side face S of the punch tip part 2.SELECTED DRAWING: Figure 1

Description

The present invention relates to a punch structure for punching a press-formed product having a predetermined shape from a metal plate to be pressed, which is provided in a press die, a press die, a method for manufacturing the press-formed product, and a press-formed product. In particular, when manufacturing a press-formed product including a narrow portion whose width is narrow with respect to the thickness, a technique capable of effectively preventing the occurrence of damage to the punch structure repeatedly used in the punching process is proposed. It is a proposal.

In manufacturing a connector or a lead frame, it is common practice to form a terminal portion by press molding in which a metal plate such as a copper alloy as a work material is pressed and punched.
In recent years, with the downsizing of equipment, the connector terminals built into it have also tended to become finer. In press molding, it is necessary to punch into a fine and complicated shape, and the press molded product is difficult. Dimensional tolerances are required.

Under such circumstances where the press-molded products are becoming finer and more complicated, the width (w/t) of the width w to the thickness t is 1. There may be a narrow portion of 5 or less. In this case, when such a press-formed product is manufactured, if a punching process is performed in a plurality of times, for example, one side and the other side of the narrow portion are sequentially punched, so-called rolling occurs. Easier to do.

More specifically, this rolling becomes a narrow width portion when punching one side portion at the time of the first punching of a plurality of punching processes and punching the other side side at the time of the subsequent punching processing. Since the width of the material portion is narrow, the portion sandwiched between the punch and the die is displaced to the side opposite to the fracture surface during the subsequent punching process. When rolling occurs, the dimensions of the press-formed product are not stable and it becomes difficult to meet strict dimensional tolerances. Note that, as a technique focusing on this type of problem, there is one described in Patent Document 1, for example.

JP, 2007-326105, A

Various countermeasures can be considered for the above-mentioned fall, and as one of them, the technique of integrated punching or double-side punching is effective. According to this, since both sides of the narrow width portion are punched at the same time, no rolling occurs and it is possible to form a stable shape even in the narrow width portion having a width/thickness ratio of 1.5 or less. Is.

However, when performing such integral punching, the shape of the tip surface of the punch structure of the press die needs to be a shape that includes the same narrow width shape as the narrow width portion. There is a problem in that the strength of the punch structure is reduced, and as a result, damage such as cracks occurs in a predetermined portion of the punch structure with use.

The present invention has an object to solve the above-mentioned problems, and an object thereof is to perform a punching process in manufacturing a press-formed product including a narrow portion whose width is narrow with respect to the thickness. It is an object of the present invention to provide a punch structure, a press die, a method for manufacturing a press-molded product, and a press-molded product that can effectively prevent damage to a repeatedly-used punch structure.

The punch structure of the present invention is a punch arranged so as to protrude from the press die main body so as to punch a press-formed product including a narrow width portion having a ratio of width w to thickness t (w/t) of 1.5 or less. A structure, having a punch tip portion having a tip surface including at least a portion of a narrow shape corresponding to the planar shape of the narrow portion of the press-formed product, on a part of the side surface of the punch tip portion, Reinforcing ribs extending in the protruding direction of the punch structure are provided.

INDUSTRIAL APPLICABILITY The punch structure of the present invention is particularly effective for a punch structure for punching a press-formed product including two narrow width portions that are spaced apart from each other and a connecting portion that connects the narrow width portions to each other. In this case, it is preferable that the punch tip has a tip surface including at least a portion of a narrow shape and a connecting shape corresponding to the planar shapes of the narrow portion and the connecting portion of the press-formed product.

Further, in this case, it is preferable that the reinforcing rib is located at an end portion of the narrow tip shape of the punch tip portion, which is apart from the connecting shape.
Further, here, it is preferable that the reinforcing rib is provided on each of both side surfaces that separate the narrow width shape at at least one of the end portions of the narrow width shape.

In the punch structure of the present invention, it is preferable that the reinforcing rib is provided continuously from the tip surface of the punch tip portion in the protruding direction over a length that is 3 to 50 times the thickness t of the narrow portion. ..

Further, in the punch structure of the present invention, it is preferable that the reinforcing rib has a rectangular cross-sectional shape.
Here, preferably, in the cross-section of the reinforcing rib, the width of the reinforcing rib parallel to the side edge of the narrow shape is 0.3 to 4 in terms of the ratio to the width w of the narrow portion. ..
Further, preferably, in the cross-section of the reinforcing rib, the height of the reinforcing rib orthogonal to the side edge of the narrow width shape is expressed by a ratio to the width w of the narrow width portion, and is 0.3 to 4. Is.

Further, in the punch structure of the present invention, it is preferable that the reinforcing rib has a constant transverse shape over the entire reinforcing rib in the projecting direction.

The press die of the present invention has any of the punch structures described above.

The method for producing a press-formed product of the present invention is to produce a press-formed product by punching a metal plate using a press die having any one of the punch structures described above.
More specifically, the method for producing a press-formed product according to the present invention is, in more detail, sequentially performing a plurality of stages of punching processes including a pre-stage punching process and a subsequent post-stage punching process on a metal plate. In one of the punching processes, a primary punching point is formed by using the punch structure in which the reinforcing rib is provided at the punch tip, and in the other punching process, the primary punching point is crossed and the primary punching point is reinforced. It is possible to form a secondary punching portion by punching including a portion where the rib penetrates.

In this manufacturing method, it is preferable that the other punching process for forming the secondary punching site is the pre-stage punching process and the one punching process for forming the primary punching site is the post-stage punching process.

The press-formed product of the present invention includes a narrow portion having a width w to thickness t ratio (w/t) of 1.5 or less, and a side surface around the narrow portion serves as a punching surface of the press. A molded article,
A rib matching for partitioning the secondary punching surface from the primary punching surface is formed on a part of the side surface of the narrow portion.

In the press-formed product of the present invention, the two narrow width portions that are spaced apart from each other and arranged side by side, and a connecting portion that connects the narrow width portions to each other are provided. It is preferable that the side surface be a punched surface of the press.

Further, in the press-formed product of the present invention, it is preferable that the secondary punching surface is located on a side surface of an end portion of the narrow width portion, which is separated from the connecting portion.
Further, in the press-formed product of the present invention, it is preferable that at least one end portion of the narrow width portion is provided with the secondary punching surface on each of both side surfaces of the narrow width portion.

It is preferable that the secondary punched surface of the press-formed product is formed so as to be recessed from the primary punched surface.
In this case, it is preferable that the depression amount of the secondary punching surface is 10% to 20% with respect to the width w of the narrow width portion, measured along the width direction of the narrow width portion. ..

In the press-formed product of the present invention, the ratio (w1/t) of the width w1 to the thickness t of the narrow width portion at the position where the secondary punched surface is formed is 0.5 to 1.5. preferable.

In the press-formed product according to the present invention, the press-formed product has a sag surface and a burr surface, and in a cross section, a surface portion of the burr surface that is parallel to the sag surface or that slopes to the right and tilts to the right It is preferable that the area ratio of the larger surface portion of the surface portions to be formed is 90% or more.
In this case, it is preferable that the inclination angle of the larger surface portion with respect to the sag surface in the cross section is within a range of 0° to 20°.

According to the present invention, a reinforcing rib extending in the protruding direction of the punch structure is provided on a part of the side surface of the punch tip of the punch structure, so that cracking at a predetermined portion of the punch structure can be suppressed. .. As a result, even when this punch structure is repeatedly used for punching a press-formed product including a narrow portion whose width is narrow with respect to the thickness, it is possible to effectively prevent damage to the punch structure. it can.

It is a perspective view showing a punch tip part of a punch structure of one embodiment of this invention. FIG. 2 is a perspective view schematically showing a press-formed product to be formed using the punch structure of FIG. 1. It is a partial top view which illustrates damage of the front end surface of the conventional punch structure. It is a top view which shows typically the deformation|transformation aspect of the front end surface at the time of punching, and the location where the tensile stress is concentrated. It is a perspective view which shows the other example of arrangement|positioning of the reinforcement rib of the punch structure shown in FIG. It is a cross-sectional view of the punch tip portion of the punch structure shown in FIG. It is a perspective view which shows the modification of the reinforcement rib of a punch structure shown in FIG. 1, and another example of arrangement|positioning. It is a perspective view which shows the punch front-end|tip part of the punch structure of other embodiment. It is a top view which shows the manufacturing method of the press molded article of one embodiment of this invention. It is a top view which shows the manufacturing method of the press-molded article of other embodiment. It is a top view and a side view showing a press-molded article of one embodiment of this invention. FIG. 12 is an enlarged plan view of an end portion of the narrow width portion of the press-formed product shown in FIG. 11. FIG. 12 is a cross-sectional view of a narrow portion and a connecting portion along each of the aa line, the bb line, and the cc line in FIG. 11A. It is the top view which shows the measuring method of an area ratio, and the side view shown in the state before and behind grinding. It is a cross-sectional view of a press-formed product showing a method for measuring an area ratio. It is a cross-sectional view of the narrow portion and the connecting portion of the press-formed product of the reference example. It is a top view which shows the press-molded article of other embodiment. 7 is a perspective view showing a punch tip portion of a punch structure of Comparative Example of Test Example 1. FIG. 9 is a plan view showing a method for manufacturing a press-formed product by punching out in Test Example 5. FIG. FIG. 8 is a cross-sectional view of a press-formed product formed by integral punching and overtaking in Test Example 5. FIG. 6A is a front view and a side view showing a state in which a molded product of Test Example 6 is embedded in a resin product and bent. 8 is a plan view showing a T-shaped molded product of Test Example 7. FIG.

Embodiments of the present invention will be described in detail below with reference to the drawings.
(Punch structure)
The punch structure 1 according to one embodiment of the present invention is provided on one of an upper die and a lower die of a press die body (not shown) such as a progressive die to punch a press-formed product from a metal plate to be pressed. It is a columnar member that is arranged so as to project from the press die body.
More specifically, as illustrated in FIG. 1, the punch tip portion 2 of the punch structure 1 has a tip surface T that abuts and penetrates a metal plate to be pressed, and the tip surface T is It is formed in a shape corresponding to a predetermined plane shape of the press-formed product.

Here, as an example, the target press-formed product 21 to be finally manufactured is, as schematically shown in FIG. 2, arranged side by side in a plan view and spaced apart from each other, for example, with different lengths. Two narrow width portions 22 and 23 that extend substantially parallel to each other and a narrow width portion 22 and 23 extend between the narrow width portions 22 and 23, for example, while changing the width. And has a substantially "H" shape that is composed of a connecting portion 24 that is connected at an intermediate position in the extending direction. In this press-formed product 21, the ratio (w/t) of the width w to the thickness t of the narrow width portions 22 and 23 is 1.5 or less.

Correspondingly, the tip surface T of the punch tip portion 2 has a narrow width shape corresponding to the planar shape of the narrow width portions 22 and 23 in which the ratio (w/t) of the width w to the thickness t is 1.5 or less. For example, the narrow width shapes 3 and 4 that substantially match the planar shapes of the narrow width portions 22 and 23 are included in at least a part thereof. To explain the illustrated embodiment in detail, the tip end surface T of the punch tip portion 2 has two narrow width shapes 3 and 4 and two narrow width shapes 3 and 4 which are spaced apart from each other and are substantially similar to the press-formed product 21. And a connecting shape 5 for connecting 4 to each other. The narrow shapes 3 and 4 extend in a substantially straight line substantially parallel to each other, and the connecting shape 5 extends while varying in width to form an intermediate position in the extending direction of the narrow shapes 3 and 4. Are connecting them with.

As described above, the punch structure 1 has the tip end surface T having a shape substantially corresponding to the planar shape of the press-formed product 21, so that when the press-formed product 21 is punched out from the metal plate, the narrow width portion 22 is formed. Since both side portions of 23 and 23 are pressed by a die, a stripper, or the like (not shown), the narrow portions 22 and 23 and the connecting portion 24 are integrally removed, so that the above-mentioned problem of dimensional stability due to rolling is unlikely to occur.

On the other hand, in the punch structure 1 described above, the widths of the narrow width shapes 3 and 4 and the connecting shape 5 of the tip end surface are extremely narrow because the fine press-formed product 21 can be integrally punched. As a result, when the conventional punch structure is repeatedly used, there is another problem that cracks such as cracks or other damage occur at a predetermined position on the tip surface T early with a small number of shots.

In order to deal with this problem, in the punch structure 1 of this embodiment, as illustrated in FIG. 1, the protruding direction of the punch structure 1 is formed on a part of the side surface S of the punch tip 2 that is substantially parallel to the protruding direction. Reinforcing ribs 6 extending in the direction are provided.
According to this, the tip end surface T of the punch tip end portion 2 has a fine narrow width shape 3 for punching out the narrow width portions 22 and 23 in which the ratio (w/t) of the width w to the thickness t is 1.5 or less. Even in the punch structure 1 having 4 and 4, the displacement of the portion having the narrow width shapes 3 and 4 due to the force which the punch structure 1 receives from the metal plate to be pressed when punching with the punch structure 1 is reinforced. Since it is suppressed by the rib 6, it is possible to effectively prevent the occurrence of damage on the tip end surface T.

The inventor has found that the cause of damage to the tip surface in the punch structure including the narrow shape and the connecting shape on the tip surface as shown in the drawing, the place where the reinforcing rib 6 of the punch tip portion 2 is provided, its shape, and other optimum conditions. The following examinations were conducted in order to find the appropriate conditions.

When the conventional punch structure having no reinforcing rib 6 was repeatedly used, the tip surface was damaged with a small number of shots. When the breakage that occurred on the tip surface was confirmed, it was found that in many punch structures, the crack C1 in the connecting shape portion between the narrow width shapes as shown in FIG. 3(a) and as shown in FIG. 3(b). It was found that there is a crack such as a crack C2 extending inward from the outer edge side of the middle portion of the longer narrow shape.

Then, from the results of investigating the side surfaces of these punch structures whose tip surfaces were damaged, it was hypothesized that the lateral force acting on the side surface of the punch tip part during punching had an effect on the damage of the tip surface, In order to verify this, a simulation was performed in which the lateral force was added as a condition in addition to the punching load.
From the simulation in which the lateral force is added, the result that the tensile stress is concentrated is the part of the connecting shape between the narrow width shapes or the outer edge of the middle part of the longer narrow width shape. Since this coincides with the above-mentioned damage points such as cracks C1 and C2 on the tip end surface, it was found that the lateral force at the time of punching greatly affects the breakage of the tip end surface.

That is, in punching, not only the punching load in the direction parallel to the projecting direction but also the extension portion having a particularly long narrow width as shown in FIGS. It is considered that lateral force acts from the lateral side, as shown by. As shown in FIG. 4A, when the lateral force acts from the inner edge side which is the shorter narrow width side toward the outer edge side, as shown by the broken line in FIG. The tensile stress concentrates on the part closer to the shape. On the other hand, as shown in FIG. 4B, when the lateral force acts from the outer edge side toward the inner edge side, as shown by a broken line in the figure, the central portion of the connection shape or the central portion of the long narrow width shape The tensile stress concentrates on the outer edge. Then, cracks occur at these stress concentration points.

Therefore, in order to suppress the stress concentration due to the lateral force as described above, it is effective to prevent the breakage by providing the reinforcing rib 6 on a part of the side surface S of the punch tip 2 so as to oppose the lateral force. Is.
Specifically, as shown in FIG. 1, the reinforcing ribs 6 are preferably arranged at the end portions of the narrow width shapes 3 and 4 of the punch tip portion 2 which are located apart from the connecting shape 5. Since the ends of the narrow shapes 3 and 4 are largely displaced by the lateral force during punching, the reinforcing ribs 6 are arranged here to suppress the displacement, whereby the tensile stress is concentrated at a predetermined position. As a result, the occurrence of cracks can be prevented more effectively. In FIG. 1, reinforcing ribs 6 are arranged at both ends of the long narrow shape 3 and both ends of the short narrow shape 4, respectively.

Further, in this case, the reinforcing rib 6 is provided on each of the side surfaces S that separate the narrow shapes 3 and 4 at least at one end of the narrow shapes 3 and 4, that is, It is preferable that the end portions are located so as to be sandwiched from both side surfaces S side. As a result, the ends of the narrow shapes 3 and 4 which are largely displaced during punching are restrained from both sides by the reinforcing ribs 6, and the effect of preventing cracks is further enhanced. However, due to restrictions on the space for arranging the reinforcing ribs 6 and other reasons, in the punch structure 1 shown in FIG. 1, the reinforcing ribs 6 are provided only on the ends of the extended portion of the long narrow width shape 3 on both sides of the end. And the reinforcing rib 6 is provided only on one side of the outer edge side at the other end. Note that, as illustrated in FIG. 5, the reinforcing ribs 6 may be provided on only one side at all the ends of the narrow shapes 3 and 4.

Regarding the size and shape of the reinforcing rib 6, from the simulation result, the reinforcing rib 6 is directed toward the base side from the tip surface T of the punch tip 2 toward the base side along the protruding direction, and the narrow width portion 22 of the press-formed product 21 to be manufactured. , 23 is preferably provided continuously over a length of 3 to 50 times the thickness t. When the length Lr of the reinforcing rib 7 in the protruding direction is set to be greater than 50 times the thickness t of the narrow width portions 22 and 23, there is a concern that the cutting edge may have insufficient strength (warp, tilt, etc.). Also, as in other examples described later, when the reinforcing rib extends from the base side to the front side to the tip side, damage is caused from the reinforcing rib apex portion (for example, the joint between the punch tip side surface and the triangular rib acute angle portion). there's a possibility that.

From the simulation result, the reinforcing rib 6 has a rectangular cross-sectional shape, and in particular, as shown in FIGS. 1 and 5, a rectangular columnar shape having a rectangular cross-sectional shape with a constant area over the entire protruding direction. It is preferable that This is because such a rectangular column-shaped reinforcing rib 6 can more effectively suppress the deformation of the punch tip portion 2 due to the stress in the direction shown by the arrow in FIG. 4, as compared with a triangular rib described later.

Further, as shown in FIG. 6, the reinforcing rib 6 has a width Wr parallel to the side edges of the narrow width shapes 3 and 4 of the reinforcing rib 6 in a cross section orthogonal to the protruding direction. The ratio of the widths w of the narrow portions 22 and 23 is preferably 0.3 to 4. When the width Wr of the reinforcing rib 6 is too narrow with respect to the width w of the narrow width portions 22 and 23, the reinforcing effect may decrease. On the other hand, the width Wr of the reinforcing rib 6 may decrease. If the width w is too wide, it is undeniable that the reinforcing rib 6 and the side surface S of the punch tip 2 may be damaged at the joint.

Further, as shown in FIG. 6, the reinforcing rib 6 has a height Hr orthogonal to the side edges of the narrow width shapes 3 and 4 in the horizontal cross section of the reinforcing rib 6, and the narrow width portions 22 and 23. It is preferably 0.3 to 4 in terms of the ratio to the width w. If the height Hr of the reinforcing rib 6 is too low with respect to the width w of the narrow width portions 22 and 23, the reinforcing effect may decrease, and the height Hr of the reinforcing rib 6 may decrease. If the width w is too high, it is feared that the reinforcing rib 6 and the side surface S of the punch tip 2 may be damaged at the joint.

However, the reinforcing ribs may have the dimensions and shapes shown in FIG. 7, for example.
In the example shown in FIG. 7A, the reinforcing rib 6a has a substantially right-angled triangular shape in a side view, and its cross-sectional shape has an area that increases from the base side of the punch structure 1 toward the tip surface T side. It has a gradually decreasing rectangular shape (triangular rib). The reinforcing rib 6a having such a shape is arranged so as to extend from the base portion side to an intermediate position in the projecting direction that does not reach the front end surface T.

In the example shown in FIG. 7B, the reinforcing ribs 6a having the same shape are provided on the outer surface of the short narrow shape 4 and between the reinforcing ribs 6a provided at both ends of the narrow width shape 4, respectively. It is the same as that shown in FIG. 7A except that.
In the example shown in FIG. 7(c), the one shown in FIG. 7(a) except that all the reinforcing ribs 6a in FIG. 7(a) are replaced with reinforcing ribs 6b extending to the tip surface T longer than that. Is the same as.
Depending on the shape of the tip surface T of the punch tip 2 and other conditions, the dimension and shape illustrated in FIG. 7 may be preferable.

In the above-mentioned place, as shown in FIG. 2, two narrow width portions 22 and 23, which are spaced apart from each other and extend side by side, and the narrow width portions 22 and 23 are connected to each other at an intermediate position in the extending direction. In order to punch out the press-formed product 21 including the connecting portion 24, the punch structure 1 of the tip end surface T including the narrow width shapes 3 and 4 and the connecting shape 5 corresponding to the planar shape thereof has been described, but the shape is different. When punching a press-formed product, the shape of the punch structure can be appropriately changed according to the plane shape.

For example, in the punch structure 31 shown in FIG. 8A, the tip end surface is continuous with the narrow width shape 33 extending linearly and one end of the narrow width shape 33, and is substantially orthogonal to the narrow width shape 33. And has a narrow width shape 34 that extends linearly with a length shorter than the narrow width shape 33 and forms a substantially "L"-shaped planar shape. Here, reinforcing ribs 36 are provided on both sides of the other end of the long narrow shape 33.

The punch structure 41 shown in FIG. 8(b) has two long and short narrow width shapes 43 and 44 extending linearly in parallel with each other, and between the two narrow width shapes 43 and 44 in a direction substantially orthogonal to them. It has a tip surface T that extends and includes a connecting shape 45 that connects the middle portion of the long narrow shape 43 to one end of the short narrow shape 44. In the punch structure 41, the reinforcing ribs 46 are provided on both sides of one end of the long narrow shape 43, and at the other end of the long narrow shape 43 and the other end of the short long narrow shape 43, only one side is outside. Reinforcing ribs 46 are provided on the.
In the punch structure 51 shown in FIG. 8C, a portion of the long narrow shape 53 on the other end side of the connection shape 55 is removed, and the other end of the long narrow shape 53 and one end of the short narrow shape 54 are removed. It has substantially the same structure as the punch structure 41 of FIG. 8B except that and are connected to the connecting shape 55.

(Method for manufacturing press-formed products)
A predetermined press-formed product can be manufactured by punching a metal plate using a press die having the punch structure 1, 31, 41 or 51 as described above. The press die can be incorporated into a progressive die or the like and an existing one can be used except for the punch structure and the structure related thereto, and therefore detailed description and illustration thereof are omitted here.
A manufacturing method using the punch structure 1 will be described below as an example, but a method using another punch structure 31, 41, 51 or the like can be performed in substantially the same manner.

Since the punch structure 1 is provided with the reinforcing ribs 6, depending on the arrangement mode of the reinforcing ribs 6, when a metal plate is punched using the punch structure 1, the portions of the metal plate through which the reinforcing ribs 6 are punched are also punched. In some cases, a convex portion corresponding to the cross-sectional shape of the reinforcing rib 6 is inevitably formed on the side surface of the molded product thus formed, which corresponds to the reinforcing rib 6.
In order to deal with this, it is preferable that the metal plate is sequentially subjected to a plurality of stages of punching processes including a pre-stage punching process and a subsequent post-stage punching process.

Specifically, for example, first, as shown in FIG. 9A, the metal plate 61 is punched using the punch structure 1 having the reinforcing ribs 6. As a result, a semi-finished product 62 as shown in FIG. 9B can be punched out and molded from the metal plate 61. As a result of being formed using the punch structure 1 described above, the semi-finished product 62 is, as shown in FIG. Protrusions 63 having a rectangular shape or the like corresponding to the cross-sectional shape of the reinforcing rib 6 are formed at the portions corresponding to the sides of both ends of the width shape and protruding from the side surface. The entire side surface of the semi-finished product 62 including the convex portion 63 becomes the primary punching location Sp1. Further, here, this punching process using the punch structure 1 is a pre-stage punching process performed prior to the punching process described below.

Next, in order to remove the above-mentioned convex portion 63 of the semi-finished product 62, as shown in FIG. 9C, using the punch structures 1a to 1e different from the punch structure 1, the primary punching location Sp1 of the semi-finished product 62 is used. And the punching process is performed including the portion where the above-mentioned reinforcing rib 6 penetrates and the convex portion 63 is formed. By this punching process, as shown in FIG. 9D, it is possible to obtain the press-formed product 71 in which the secondary punching portion Sp2 is formed at the portion where the convex portion 63 was present. In this case, this punching process using the punch structures 1a to 1e becomes a post-stage punching process because it is later in time than the above-mentioned pre-stage punching process.

It is possible to punch the semi-finished product 62 at the same time with all the punch structures 1a to 1e. However, at least one of the punch structures 1a to 1e is used by being temporally displaced from the remaining punch structures, It is also possible to sequentially perform punching by these. That is, the second-stage punching process may be further divided into a plurality of stages.

In this embodiment, the punch structures 1a to 1e allow the press-formed product 71 to have a slightly wider width than each of the protrusions 63 and punch into the narrow width part of the semi-finished product 62 in plan view. The place where the convex portion 63 on the side surface was present is slightly depressed, and in the vicinity of both sides of the place, matching that forms a boundary between the primary punching place Sp1 and the secondary punching place Sp2 is formed. Although illustration is omitted, it is also possible to punch the convex portion 63 with the punch structures 1a to 1e with a slight distance from the narrow width portion of the semi-finished product 62. In this case, in the press-formed product, the convex portion 63 is formed. A protrusion from the side surface is formed by the remaining portion of the. Details of the press-formed product 71 will be described later.

In this way, by manufacturing the press-formed product 71 using the punch structure 1, by providing the reinforcing ribs 6 as described above, damage to the tip end surface of the punch structure 1 is prevented and the width w with respect to the thickness t. It is possible to effectively manufacture the press-formed product 71 having a narrow portion having a ratio (w/t) of 1.5 or less.

Alternatively, it is possible to manufacture the press-formed product 71 as shown in FIG.
In this embodiment, first, as shown in FIG. 10A, as a pre-stage punching process, a punching process is performed on the metal plate 61 using the punch structures 1a to 1e, and as shown in FIG. The metal plate 61 is provided with a secondary punching location Sp2 which is a void corresponding to each punch structure 1a to 1e. At this time, the punching process by the punch structures 1a to 1e is a post-stage punching process described later, in which the primary punching site Sp1 of the post-stage punching process intersects with the secondary punching site Sp2 of the punch structure 1 used in the post-stage punching process. It is performed at a position including a portion where the reinforcing rib 6 will penetrate.

The punching processes using the punch structures 1a to 1e can be performed all at the same time, or can be performed separately at least one of them at different times.

After that, as shown in FIG. 10B, as a post-stage punching process, the punching process is performed on the metal plate 61 on which the secondary punching spot Sp2 is formed by using the punch structure 1 provided with the reinforcing ribs 6. As a result, as shown in FIG. 10(c), the metal plate 61 as scrap in which cavities penetrating the front and back sides at the primary punching location Sp1 and the secondary punching location Sp2 are formed, and as shown in FIG. 10(d). In addition, it is possible to obtain a press-formed product 71 which is substantially the same as that described above.

In the manufacturing method shown in FIG. 10, the punching process for forming the secondary punching spot Sp2 by the punch structures 1a to 1e is the pre-stage punching process, and the punching process for forming the primary punching spot Sp1 by the punch structure 1 provided with the reinforcing ribs 6 is performed. The use of the second-stage punching has an advantage that scrap generation of scrap can be suppressed as compared with the manufacturing method shown in FIG. In the manufacturing method shown in FIG. 9, since the size of the punched shape at the stage of FIG. 9C is small, it is undeniable that scrap residue is likely to occur. Therefore, the manufacturing method shown in FIG. 10 is more suitable than that shown in FIG.

The manufacturing method shown in FIG. 9 or 10 can be implemented by partially modifying it.
As a modification, for example, although not shown, it is conceivable that the punching process using at least one of the punch structures 1a to 1e is performed before or after the punching process using the punch structure 1. That is, in this modified example, first, punching with at least one of the punch structures 1a to 1e is performed, then punching with the punch structure 1 is performed, and then the remaining punching of the punch structures 1a to 1e is performed. To do.
Further, the planar shape of the punch structures 1a to 1e is substantially "L"-shaped in the illustrated embodiment, but it can be changed to a rectangular shape, a square shape, or another shape.
Such various changes/improvements can be appropriately made according to the shape of the press-formed product to be manufactured, the form of the mold, and other conditions.

In the above description, the terms "primary" and "secondary" of the primary punching location Sp1 and the secondary punching location Sp2 are simply the locations formed by using different punch structures 1 and punch structures 1a to 1e. Only means there is. The same applies to the primary punching surface and the secondary punching surface of the press-formed product described later.

(Press-molded product)
As shown in FIGS. 11A and 11B, the press-formed product 71 manufactured as described above has a narrow width ratio (w/t) of the width w to the thickness t of 1.5 or less. The press-formed product 71 has the width portions 72 and 73, and the entire side surface of the press-formed product 71 including the side surfaces of the narrow-width portions 72 and 73 serves as the punching surface of the press. In particular, when the ratio (w/t) of the width w to the thickness t of the narrow width portions 72 and 73 is 1.0 or less, and further 0.8 or less, the narrow shape of the punch structure 1 for forming it. It is even more effective to apply the present invention because the finer parts 3 and 4 are likely to be displaced during punching and the problem of breakage becomes remarkable. Usually, the ratio (w/t) of the width w to the thickness t of the narrow width portions 72 and 73 is often 1.0 or more.

Note that, as shown in FIG. 11( b ), the punching surface of the press is generally configured to include one or more shearing surface regions and fracture surface regions extending side by side in the direction in which the side surfaces extend (the horizontal direction in the figure). It The sheared surface region is considered to be formed by rubbing against the punch or die when the metal plate is stretched in the thickness direction by punching, and becomes a smooth surface with a slight linear pattern in the thickness direction. On the other hand, the fracture surface region is considered to be caused by being torn from the scrap discharged after being stretched by punching, and is a dimple-like surface having irregularities, which is distinctly different from the shear surface region.

The press-formed product 71 of this embodiment is composed of two narrow width portions 72 and 73 that are spaced apart from each other in a plan view and a connecting portion 74 that connects the narrow width portions 72 and 73 to each other. The one narrow portion 72 has an extension portion that extends longer than the other narrow portion 73 on one end side thereof.

Since the press-formed product 71 is manufactured by the above-described method, the entire side surfaces of the narrow width portions 72, 73 and the connecting portion 74 are composed of the primary punching surface Fp1 and the secondary punching surface Fp2, and A rib matching Mr that extends in the thickness direction and divides the primary punching surface Fp1 from the secondary punching surface Fp2 is formed on a part of the side surfaces of the width portions 72, 73.
The rib matching Mr has a surface property of a shearing surface area and a fracture surface area between the primary punching surface Fp1 formed by the punch structure 1 having the reinforcing ribs 6 and the primary punching surface Fp1 formed by the punch structures 1a to 1e. Exists at a transition position between different secondary punching surfaces Fp2, and in many cases, as in the illustrated embodiment, it has a corner shape that is convex outward as a cut-and-connect shape.

In this embodiment, in the primary punching surface Fp1 and the secondary punching surface Fp2 defined by the rib matching Mr, the formation positions of the shearing surface area and the fracture surface area are as shown in FIG. 11(b). The press-formed products 71 are turned upside down in the thickness direction, and are in mutually opposite positions. This is because the punching process in which the primary punching surface Fp1 is formed and the punching process in which the secondary punching surface Fp2 is formed are upside down in the arrangement positions of the punch and the die.

The secondary punching surface Fp2 sandwiched by the rib matching Mr in the direction in which the side faces extend has the reinforcement ribs 6 of the narrow shapes 3 and 4 in order to more effectively prevent damage to the tip end surface T of the punch structure 1 as described above. Due to the provision of the end portions, in the illustrated embodiment, the narrow portions 72, 73 are located on the respective side surfaces of the end portions of the narrow portions 72, 73 which are separated from the connecting portion 74.
Further, in this embodiment, as described above, the secondary punching surface formed at the end of the extended portion of the long narrow portion 72 of the press-formed product 71 corresponding to the position of the reinforcing rib 6 on the punch structure 1. Fp2 will be located on each of both side surfaces that separate the narrow portion 72.

Further, here, as described above, the punch structures 1a to 1e bite into the narrow width portion to perform the punching process, so that in the press-formed product 71, any of the secondary punching surfaces Fp2 is subjected to the primary punching. It is formed so as to be recessed from the surface Fp1.
In this case, the recess amount D of the secondary punching surface Fp2 is measured along the width direction (vertical direction in the figure) of the narrow width portions 72 and 73, as shown in FIG. It is preferably within the range of 10% to 20% with respect to the width w. This means that when the recess amount D of the secondary punching surface Fp2 is less than 10% of the width w of the narrow width portions 72 and 73, a defect (burr or the like) may occur when the punching position is displaced. On the other hand, when the depression amount D of the secondary punching surface Fp2 exceeds 20% of the width w of the narrow width portions 72 and 73, the depression amount D is excluded from the width w of the narrow width portions 72 and 73. This is because there is a concern that the width w1 becomes small and the narrow portion is deformed.
However, although not shown in the drawings, at least one of the secondary punching surfaces may be a protrusion that projects from the primary punching surface, depending on the punching mode of the punch structures 1a to 1e.

As described above, when the secondary punching surface Fp2 is in the shape of a depression or a protrusion, the widths of the narrow width portions 72 and 73 are slightly changed, and the narrow width at the location where the secondary punching surface Fp2 is formed. The ratio (w1/t) of the width w1 to the thickness t of the width portions 72 and 73 is preferably 0.5 to 1.5. When the width w1 of the narrow width portions 72, 73 at the location where the secondary punching surface Fp2 exists is too narrow and this ratio (w1/t) is less than 0.5, the narrow width portion is deformed (falls). There is a risk of Therefore, it is even more preferred that this ratio (w1/t) is between 1.0 and 1.5.

By the way, the press-formed product 71 has a curved sag that curves in a direction in which the thickness of the press-formed product 71 is gradually reduced, as shown in the cross-sectional view of the narrow portions 72, 73 and the connecting portion 74 in FIG. It has a sag surface 75 that can be obtained and a burr surface 76 that can form a burr protruding from the surface. In general, the surface of the side surface adjacent to the shear surface area side of the shear surface area and the fracture surface area is the sag surface 75, and the surface on the back side adjacent to the side surface of the fracture surface area is the burr surface 76. ..

Due to the fact that the above press-molded product 71 is manufactured by integral punching, the inclination direction of most of the burr surface 76 is the same as the inclination direction of the sag surface 75 when viewed in a cross section. Become. In this case, most of the burr surface 76 has a single surface roughness because the polishing marks on the tip surface of the single die or the punch are transferred by contact with the single die or the punch. There is.

Specifically, in the cross section, the area ratio AR of the larger surface portion of the surface portion of the burr surface 76 parallel to the sag surface 75 or inclined to the lower right and the surface portion inclined to the upper right. Is preferably 90% or more. That is, if 90% or more of the surface of the burr surface 76 has the same inclination with respect to the sag surface 75, it can be said that it is preferable because it is manufactured by integral drawing and the dimension is stable. More preferably, the area ratio AR of the larger surface portion of the burr surface 76 is 95% or more.

Here, the area ratio AR is measured as follows.
First, as shown in FIG. 14, the press-molded product 71 is fixed with a clip 151, and in this state, the entire periphery of the press-molded product 71 is solidified with a resin material 152. Next, as shown by the arrow in FIG. 14B, the resin material 152 is cut or polished until the cross-sectional position to be observed is reached. Further, the polishing surface including the cross section of the press-formed product 71 exposed thereby is finished by buffing. Then, the cross-sectional shape is photographed with an observation device such as a microscope, and the area ratio AR is measured.
Regarding the cross-sectional shape photographed by the observation device, first, as illustrated in FIG. 15, two boundary points Bp1 and Bp2 with each sag are removed except for sagging portions (unsteady portions) at both ends of the sag surface 75. A straight line that passes is defined as a reference line RL. Then, this reference line RL is moved in parallel to the burr surface 76 side as shown by the arrow in FIG. 15, and is compared with the burr surface 76 (a part excluding the burr part when burrs are generated at the corners). Here, in the width direction of the cross section, the surface of the burr surface 76 that is parallel to the reference line RL or the surface that slopes downward to the right, and the direction of the slope change at the transition point Tp with the surface of the surface. The length of the surface portion inclined to the upper right is measured, and the longer one of them is defined as the area ratio AR. In the area shown in FIG. 15A, since the entire burr surface 76 is parallel and coincides with the reference line RL, the area ratio AR has a value close to 100%. On the other hand, when the cross-sectional shape is distorted as shown in FIG. 15B, the length L1 of the surface portion substantially parallel to the reference line RL is measured, and the surface inclined to the right with respect to the reference line RL is measured. The length L2 of the portion is also measured, and the longer length L2 of the lengths L1 and L2 is defined as the area ratio AR.

The inclination angle of the larger surface portion of the burr surface 76 with respect to the sag surface 75 is preferably within the range of 0° to 20°. When the inclination angle exceeds 20°, there is a concern that the narrow width portions 72 and 73 that will become pins may swing during the processing of the next step (pin variation). More preferably, the inclination angle of the larger surface portion of the burr surface 76 with respect to the sag surface 75 is 0° to 10°.

As described above, the inclination angle of the larger surface portion of the burr surface 76 with respect to the sag surface 75 is obtained by moving the reference line RL of the sag surface 75 in parallel to the burr surface 76 side in the cross-sectional view, as described above. It is measured by obtaining the slope of the approximate straight line of the contour line by the least square method with respect to the reference line RL.

On the other hand, the press-formed product of the reference example shown in FIG. 16 is not formed by integral punching, but is formed by sequentially punching out one side portion and the other side portion of the narrow width portion as described in the background art item. Therefore, a fall has occurred. In the press-formed product of FIG. 16, as can be seen from the figure, the burr surface (the lower surface of the figure) is inclined mainly to the right with respect to the sag surface (upper surface). The surface area and the surface area that is inclined downward to the right and occupy the same area as the surface area, and the area ratio described above is low. Incidentally, these surface portions may have a large difference in surface roughness due to transfer of the polishing marks on the tip surfaces of two or more different types of dies or punches.

In the above description, the press-formed product 71 having the two narrow portions 72 and 73 having different lengths and the connecting portion 74 that connects them at the intermediate position has been described as an example. A press-formed product including a narrow width portion having a ratio of width w to t (w/t) of 1.5 or less can be applied to various shapes.
As a specific example thereof, for example, as shown in FIGS. 17A, 17B, and 17C, press-molding in a shape in which the narrow width portions 82 and 83 are connected to each other in a substantially “L” shape. A shape in which the product 81 and two long and narrow narrow portions 92 and 93 are connected to each other by a connecting portion 94 orthogonal to them at an end position of the short narrow portion 93 and an intermediate position of the long narrow portion 92. Of the press-formed product 91, two long and short narrow width portions 102 and 103 which are displaced from each other in the longitudinal direction are formed at the end positions of the short narrow width portion 103 and the long narrow width portion 102. The press-formed product 101 and the like having a shape connected to each other by a connecting portion 104 orthogonal to

Next, the punch structure of the present invention was prototyped, and the effect thereof was confirmed, which will be described below. However, the description here is merely for the purpose of illustration and is not intended to be limited thereto.

(Test Example 1)
As a comparative example, as shown in FIG. 18, using a punch structure having no reinforcing rib, punching was repeatedly performed on a metal plate having a width of 8.0 mm and a thickness of 0.12 mm. The minimum width of the connecting portion of the press-formed product to be manufactured is 0.07 mm, and the stroke is 13 mm in the punching process, and the continuous stroke amount which is the number that can be pressed in 1 minute is 500 spm from the start to 200,000 shots. 800 spm from 200,000 to 3 million shots and 1000 spm from 3 to 5 million shots.
In the punch structure of the comparative example, damage was confirmed in the connection shape on the tip surface of the punch tip portion after 2 million shots.

As an example, punching was repeatedly performed under the same conditions as in the comparative example, using the punch structures shown in FIGS. 1 and 5 and FIGS. 7(a) to 7(c). As a result, the number of shots until damage is confirmed on the tip surface of the punch tip portion is 4 million shots in the punch structure shown in FIG. 1, 3 million shots in the punch structure shown in FIG. 5, and is shown in FIG. The punch structure had 1.5 million shots, the punch structure shown in FIG. 7B had 2 million shots, and the punch structure shown in FIG. 7C had 2.5 million shots.

(Test Example 2)
Using the punch structure shown in FIG. 1 in which the ratio of the length Lr of the reinforcing rib to the thickness t of the narrow width portion was changed as shown in Table 1, punching was performed under the same conditions as in Test Example 1. Was repeated. The reinforcing rib extends from the tip surface. The results, discussion and evaluation are also shown in Table 1.
From Table 1, it can be seen that the number of shots until breakage significantly increases, particularly when the reinforcing rib length magnification is in the range of 3 to 50.

(Test Example 3)
Using the punch structure shown in FIG. 1 in which the ratio of the width Wr of the reinforcing rib 6 to the width w of the narrow width portion was changed as shown in Table 2, punching was performed under the same conditions as in Test Example 1. Was repeated. The results, discussion and evaluation are also shown in Table 2.
It can be seen from Table 2 that if the ratio of the width Wr of the reinforcing rib 6 is within the range of 0.3 to 4, the damage can be prevented more effectively.

(Test Example 4)
Using the punch structure shown in FIG. 1, the ratio of the height Hr of the reinforcing rib 6 to the width w of the narrow portion was changed as shown in Table 3, and punching was performed under the same conditions as in Test Example 1. The processing was repeated. The results, consideration and evaluation are also shown in Table 3.
From Table 3, it is understood that when the ratio of the height Hr of the reinforcing rib 6 is within the range of 0.3 to 4, the damage is further suppressed and more shots are possible.

(Test Example 5)
In order to confirm the difference in cross-sectional shape of the press-formed product between the integrated punching process and the punching process, the press-molded product formed by performing the processes shown in FIGS. The press-formed products formed by performing the processing shown in FIG.
As a result, as shown in Table 4, the cross section of the press-formed product formed by the integral punching has an area ratio of almost 100% and a uniform shape on the left and right as shown in FIG. 20(a). there were. On the other hand, the cross section of the press-formed product formed by the punching process has a low area ratio and has a fall and has a distorted shape, as shown in FIG.

(Test Example 6)
A press-formed product produced as in Test Example 5 above, wherein the inclination angle of the surface portion having a single surface roughness of the burr surface with respect to the sag surface is within a range of 0° to 20°, For each of the press-formed products having an inclination angle of 30° or more, in the subsequent process, as shown in FIG. 21, one end of the narrow width portion was embedded in a resin product and bent by 90°. As a result, as shown in Table 5, when the inclination angle was in the range of 0° to 20°, there was little variation within the dimensional standard, and the side surface bent at 90° was also stable. On the other hand, when the inclination angle was 30° or more, the runout was large, and the variation in the side surface bent by 90° was large.

(Test Example 7)
As shown in FIG. 22, two types of molded products having a thickness t of 0.2 mm and a width w of different values of 0.14 and 0.32 were repeatedly manufactured with a punch having no reinforcing rib. The results are shown in Table 6.
When w/t was 1.6, the punch was not damaged even after punching 3 million shots continuously, but when w/t was 0.7, the punch was damaged immediately after continuous operation. ..

1, 1a to 1e, 31, 41, 51 Punch structure 2, 32, 42, 52 Punch tip 3, 4, 33, 34, 43, 44, 53, 54 Narrow width shape 5, 35, 45, 55 Connection shape 6, 6a, 6b, 36, 46, 56 Reinforcing rib 21, 71, 81, 91, 101 Press-formed product 22, 23, 72, 73, 82, 83, 92, 93, 102, 103 Narrow portion 24, 74 , 94, 104 Connection part 75 Drip surface 76 Burr surface 61 Metal plate 62 Semi-finished product 63 Convex part T Tip surface of punch structure S Side surface of punch structure w Width of narrow part w1 Narrow at a place where secondary punching surface exists Width of width part t Thickness of narrow part C1 and C2 Crack Lr Length of reinforcing rib Wr Width of reinforcing rib Hr Height of reinforcing rib Sp1 Primary punching point Sp2 Secondary punching point Fp1 Primary punching surface Fp2 Secondary punching surface Mr Matching for rib AR Area ratio of the surface part of the larger burr surface RL Reference line Bp1, Bp2 Boundary point

This invention is provided in the press die, punch structure for punching the predetermined shape of the press-molded product from the metal plate of the press object, a press die and are those about the press-molded product manufacturing how In particular, when manufacturing a press-formed product including a narrow portion having a narrow width with respect to the thickness, a technique capable of effectively preventing occurrence of damage to a punch structure repeatedly used for punching is proposed. It is a thing.

The present invention has an object to solve the above-mentioned problems, and an object thereof is to perform a punching process in manufacturing a press-formed product including a narrow portion whose width is narrow with respect to the thickness. punch structure can effectively prevent the occurrence of damage to the punch structure used repeatedly, press mold and is to provide a manufacturing how of the press-molded product.

The punch structure of the present invention is a punch arranged so as to protrude from the press die main body so as to punch a press-formed product including a narrow width portion having a ratio of width w to thickness t (w/t) of 1.5 or less. A punch tip having a tip surface including at least a portion of a narrow width shape corresponding to the planar shape of the narrow width portion of the press-formed product, wherein the punch tip has an extension of the narrow width shape. A reinforcing rib extending to the tip end surface in the protruding direction of the punch structure is provided on a part of the side surface on the side of the portion.

Further, in the punch structure of the present invention, it is preferable that the reinforcing rib has a constant cross- sectional shape over the entire reinforcing rib in the protruding direction.

Claims (22)

A punch structure in which the ratio (w/t) of the width w to the thickness t is 1.5 or less, and the punch structure is arranged so as to project from the press die body so as to punch out a press-formed product. A punch tip portion having a tip surface including at least a portion of a narrow shape corresponding to the planar shape of the narrow portion of the product,
A punch structure of a press die, wherein a reinforcing rib extending in a protruding direction of the punch structure is provided on a part of a side surface of a punch tip portion. It is a punch structure for punching a press-formed product including two narrow portions that are spaced apart from each other and a connecting portion that connects the narrow portions to each other, and the punch tip portion is of the press-formed product. The punch structure according to claim 1, further comprising a tip end surface including at least a portion of a narrow shape and a connecting shape corresponding to a planar shape of the narrow portion and the connecting portion. The punch structure according to claim 2, wherein the reinforcing rib is located at an end of the narrow-width shape of the punch tip portion, which is apart from the connecting shape. The punch structure according to claim 3, wherein the reinforcing ribs are provided on each of both side surfaces of the narrow width shape, the reinforcing ribs being provided on at least one of the end portions of the narrow width shape. 4. The reinforcing rib is provided continuously from the tip surface of the punch tip portion in the protruding direction over a length of 3 to 50 times the thickness t of the narrow portion. Punch structure described in. The punch structure according to any one of claims 1 to 5, wherein the reinforcing rib has a rectangular cross-sectional shape. The cross-section of the reinforcing rib, the width of the reinforcing rib parallel to the side edge of the narrow width shape is 0.3 to 4, expressed as a ratio to the width w of the narrow width portion. Punch structure. In the cross section of the reinforcing rib, the height of the reinforcing rib orthogonal to the side edge of the narrow shape is 0.3 to 4 in terms of the ratio to the width w of the narrow portion. Punch structure according to 7. The punch structure according to any one of claims 1 to 8, wherein the reinforcing rib has a constant transverse shape over the entire reinforcing rib in the projecting direction. A press die having the punch structure according to claim 1. A method for producing a press-formed product, comprising punching a metal plate to produce a press-formed product using the press die having the punch structure according to any one of claims 1 to 9. The metal plate is sequentially subjected to a multi-stage punching process including a first-stage punching process and a subsequent-stage punching process,
In either one of the first-stage punching process or the second-stage punching process, a primary punching location is formed using the punch structure in which the reinforcing rib is provided at the punch tip, and the other punching process is performed to the primary punching location. The method for manufacturing a press-formed product according to claim 11, wherein the press-formed product is formed by punching a portion including the portions where the reinforcing ribs penetrate and intersect each other to form a secondary punching portion. 13. The method for manufacturing a press-formed product according to claim 12, wherein the other punching process for forming the secondary punching site is a pre-stage punching process, and the one punching process for forming the primary punching site is a post-stage punching process. A press-formed product including a narrow portion having a ratio of the width w to the thickness t (w/t) of 1.5 or less, wherein a side surface around the narrow portion serves as a punching surface of a press.
A press-formed product, wherein a rib matching that divides the primary punching surface from the secondary punching surface is formed on a part of the side surface of the narrow portion. The two narrow width portions that are spaced apart from each other, and a connecting portion that connects the narrow width portions to each other, the side surface around the narrow width portion and the connecting portion is a punching surface of the press. 15. The press-formed product according to claim 14, wherein: The press-formed product according to claim 15, wherein the secondary punching surface is located on a side surface of an end portion of the narrow portion, which is separated from the connecting portion. The press-formed product according to claim 16, wherein the secondary punching surface is provided on each of both side surfaces of the narrow portion at at least one of the end portions of the narrow portion. The press-formed product according to claim 14, wherein the secondary punched surface is formed so as to be recessed from the primary punched surface. The press-formed product according to claim 18, wherein the depression amount of the secondary punching surface is 10% to 20% with respect to the width w of the narrow portion, measured along the width direction of the narrow portion. 20. The ratio (w1/t) of the width w1 to the thickness t of the narrow portion at the location where the secondary punched surface is formed is 0.5 to 1.5. Press-formed product described in. The press-formed product has a sag surface and a burr surface, and in the cross-section, the larger of the burr surface, which is parallel to the sag surface, is inclined to the lower right, or is inclined to the upper right The press-formed product according to any one of claims 14 to 20, wherein an area ratio of the surface portion of the product is 90% or more. 22. The press-formed product according to claim 21, wherein an inclination angle of the larger surface portion with respect to the sag surface is within a range of 0° to 20° in a cross section.