JPH10249449A - Punch holding device in press die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform positioning in the peripheral direction to the retainer of the punch, with a small number of parts and without increasing much cost. SOLUTION: The punch 3 is energized toward and unpunchable position by a spring 11 through a spring seat member 9 fit with the intermediate shaft part 3a of the punch 3. By making a select bar 13 advance to the back of the head part 3c with a large diameter of the punch 3, the punch 3 is set in a punchable position. A first flat surface part 3d formed on the side surface of the head part 3c with the large diameter and a second flat surface part 9d formed on the spring seat member 9, are abutted, and the relative rotation of the spring seat member 9 to the punch 3 is regulated. A positioning recessed part 9e formed on the outer side surface of the spring seat member 9, is fitted from the punch axial direction to a positioning pin 17 fixed on the retainer 2, and the relative rotation to the retainer 2 of the spring seat member 9 is regulated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a punch holding device for a press die which positions a punch in a circumferential direction with respect to a retainer holding the punch.

[0002]

2. Description of the Related Art Some punch holding devices in a press die are capable of switching a punch between a punchable position and a non-punchable position. That is, the punch is slidably held in the axial direction by a retainer attached to the press die, and is urged by a spring toward a non-punching position where the protruding length from the retainer is shortened. Further, there is a device in which a punching position and a punching disabled position are switched by changing the length of the punch projecting from the retainer by a select bar disposed on the base end surface side of the punch (for example, Real fairness 3
No. 4412, Japanese Utility Model Publication No. 4-2609, and Japanese Utility Model Publication No. 55-23283).

[0003]

Incidentally, the shape of the tip of the punch, that is, the shape of the portion to be a punched portion for the work may be a cross-section having a different shape, such as a rectangle. In the positional relationship, it is necessary to position the retainer in the circumferential direction so that the punch does not move in the circumferential direction.

Conventionally, in order to position the punch in the circumferential direction with respect to the retainer, a flat surface portion is formed on the side surface of the intermediate shaft portion of the punch, and a cam member acting on the flat surface portion and the cam member are locked by the retainer. Some lock screws are provided, but this increases the number of parts and the number of processed parts, which is a major cause of structural complexity and cost increase. It is also considered that the intermediate shaft portion of the punch has a different cross-section while the punch guide hole formed in the retainer has a different cross-section corresponding to the different shape of the punch. Extremely complex and high-precision ones are required, resulting in a significant cost increase. In particular, it is very difficult to machine the inner surface of the guide hole of the retainer into a different cross section.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a punch holding apparatus for a press die which requires a small number of parts and is advantageous in cost.

[0006]

In order to achieve the above object, the present invention has a first solution as follows. That is, the punch is slidably held in the axial direction by a retainer attached to the press die, and is urged by a spring toward a non-punching position where the protruding length from the retainer is shortened. The punch holding in a press die, in which a punching position and a non-punching position can be switched by changing the length of protrusion of the punch from a retainer by a select bar arranged on the base end surface side of the punch. In the apparatus, there is provided a spring seat member which is fitted to an intermediate shaft portion of the punch and is prevented from coming off by a large-diameter head formed at a base end portion of the punch, and one end of the spring is seated. The first flat surface portion for positioning is formed by partially chamfering the side surface of the large diameter head, and the spring seat member abuts on the first flat surface portion. A second flat surface portion that regulates the relative rotation between the spring seat member and the punch and positions the punch and the spring seat member in the circumferential direction is formed, and a positioning surface is formed on one of the retainer and the spring seat member. A convex portion is formed, and a positioning concave portion is formed on the other side. The positioning convex portion and the positioning concave portion are fitted to each other from an axial direction of the punch, and a circumferential direction of the spring seat member with respect to the retainer. Is performed. Preferred embodiments based on the above solution are as described in claims 2 to 8 and claim 11 in the claims.

In order to achieve the above object, the present invention is as follows as a second solution. That is,

In a press die in which a punch is held by a retainer attached to the press die, a positioning recess is formed as a notch on a side surface of a large-diameter head formed at a base end of the punch. The positioning recess is fitted into the retainer from the axial direction of the punch, and a positioning pin for positioning the punch in the circumferential direction with respect to the retainer is fixed. Preferred embodiments based on the above solution are as described in Claim 9 and the following claims.

[0009]

According to the first aspect of the present invention, the punch is switched between the punchable position and the non-punchable position. It is performed by contacting two flat surface parts,
The positioning of the spring seat member and the retainer is performed by fitting the positioning concave portion and the convex portion, and finally, the circumferential positioning of the punch with respect to the retainer is performed,
As a whole, the punch can be positioned in the circumferential direction with respect to the retainer without greatly increasing the number of parts and without significantly increasing the cost. Also,
By simply assembling the assembly of the punch and the spring seat member into the retainer with the spring seat member fitted to the punch, the circumferential positioning of the punch with respect to the retainer can be performed automatically, that is, easily.

According to the second aspect of the present invention, there is provided a more specific positioning convex portion and concave portion. However, since the positioning concave portion is formed as a cutout formed in a side surface of the spring seat member, the formation is formed. However, since the positioning pins as the positioning projections extend in parallel with the axis of the punch, the position of the punch is changed when the punch is switched between the punchable position and the non-punchable position. This is preferable in that the circumferential positioning of the punch with respect to the retainer can always be reliably performed, sufficiently responding to the large axial displacement amount.

According to the third aspect, when the assembly of the punch and the spring seat member is assembled to the retainer, even if the spring seat member approaches the positioning pin with the spring seat member slightly inclined with respect to the punch axis. By compensating for this inclination, the positioning recess formed in the spring seat member can be securely and easily fitted to the positioning pin.

According to the fourth aspect, when the punch is attached to the retainer together with the spring seat member, or when the punch is removed from the retainer together with the spring seat member, integration of the punch and the spring seat member is always ensured. Installation and removal work is facilitated.

According to the fifth aspect, it is preferable to prevent interference between the select bar and the positioning convex and concave portions. According to the sixth aspect, it is preferable to ensure that the two flat surface portions come into contact with each other reliably and easily, and to secure a contact area between the flat surface portions as large as possible.

According to the seventh aspect, a more specific spring seat member having the second flat surface portion is provided. Claim 8
According to this, the plate-shaped portion corresponding to the first portion and the second flat surface portion can be obtained at once by simply shaving a metal plate having a thickness corresponding to the second portion.

According to the ninth aspect, the punch can be positioned in the circumferential direction with respect to the retainer only by fixing the positioning pin to the retainer while forming the notch in the side surface of the large diameter head of the punch. In particular, the punch is preferable when applied to a punch holding device of a type that does not require switching between a punchable position and a non-punchable position. Claim 1
According to 0, the same effect as the effect according to claim 3 can be obtained. According to the eleventh aspect, the shape of the punching portion of the punch is suitable in a case where it is strongly required to position the punch in the circumferential direction with respect to the retainer.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 1 denotes an upper die of a press die, and a punch 3 is held on the upper die 1 via a retainer 2. The retainer 2 has a divided structure of a retainer body 4, a backing plate 5, and a side plate 6, and these 4 to 6 are integrated with each other by bolts.

A guide hole 7 is formed in the retainer main body 4 and extends vertically. The upper portion of the guide hole 7 communicates with the guide hole 7 and a storage space 8 opened on the upper surface of the retainer main body 4. The storage space 8 is covered with a backing plate 5. The punch 3 has a portion that slides in the guide hole 7 as an intermediate shaft portion 3a, a front end side of the intermediate shaft portion 3a as a punched portion 3b, and an upper portion of the intermediate shaft portion 3a than the intermediate shaft portion 3a. Is also a large diameter head 3c having a slightly larger diameter. And the guide hole 7,
Each of the intermediate shaft portion 3a and the large diameter head 3c has a circular cross-section, but the cross-sectional shape of the punched portion 3b is an irregular shape such as a substantially rectangular shape (see FIGS. 4 to 6).

A storage space 8 is provided in the intermediate shaft 3a of the punch 3.
And the spring seat member 9 is fitted without looseness (in an intermediate fit, relative displacement is not possible with a small external force), and the large diameter head 3c prevents the spring seat member 9 from coming off. In the retainer main body 4, a plurality (three in the embodiment) of spring storage recesses 10 extending in the vertical direction are formed at substantially equal intervals in the circumferential direction of the punch 3 so as to open to the bottom wall of the storage space 8. Return spring 11 arranged in each spring storage recess 10
Is in contact with the lower surface of the spring seat member 9, whereby the punch 3 is constantly urged upward.

On the upper surfaces of the retainer body 4 and the side plate 6, elongated guide grooves 12 are formed so as to extend substantially in the diameter direction of the punch and communicate with the storage space 8, and the guide grooves 12 are also formed on the backing plate. 5 covered. A select bar (also referred to as a moving backing plate) 13 is slidably fitted in the guide groove 12. The lower surface of the distal end portion of the select bar 13 is formed with a tapered inclined surface 13a that is inclined away from the large-diameter head 3c of the punch 3 that extends upward in the axial direction of the punch 3.

The base end of the select bar 13 is connected to a drive shaft 15 of a cylinder device (for example, air type or hydraulic type) 15 as an actuator via a connecting mechanism 14 described later.
a. The cylinder device 15 is fixed to the side plate 6 by bolts 16.

The spring seat member 9 has a shape as shown in FIGS. That is, the spring seat member 9 has a thin plate-shaped first portion 9a and a thick second portion 9b that is raised above one side upper surface of the first portion 9a. , A through hole 9c into which the intermediate shaft portion 3a of the punch 3 is inserted is formed. On the side surface of the second portion 9b on the side of the through hole 9c, a second flat surface portion 9d extending parallel to the axis of the punch 3 is formed. The spring seat member 9 having the first portion 9a and the second portion 9b is a metal plate having a thickness corresponding to the second portion 9b,
For example, the upper surface of the iron plate is obtained by machining only the portion corresponding to the first portion 9a by machining, and at this time, the second flat surface portion 9d can be formed at the same time. The through-hole 9c can be formed before or after forming the first portion 9a and the second portion 9b.

The first flat surface portion 3 extending parallel to the axis of the punch 3 is formed by partially chamfering the side surface of the large diameter head 3c of the punch 3 corresponding to the second flat surface portion 9d.
d is formed. When the spring seat member 9 is fitted until the first portion 9a abuts on the lower surface of the large-diameter head 3c so that the flat surfaces 3d and 9d are aligned with each other, the spring seat member 9 is brought into contact with the flat surfaces d and 9d. Due to the contact relation, the spring seat member 9 is positioned in the circumferential direction with respect to the punch 3.

The second portion 9b of the spring seat member 9 includes:
By notching a part thereof, a positioning recess (notch) 9 e extending in parallel with the axis of the punch 3 is formed. On the other hand, the retainer body 4 has positioning pins 17 as positioning projections corresponding to the positioning recesses 9e.
Has been fixed. The positioning pin 17 extends in parallel with the axis of the punch 3 and is press-fitted into a mounting hole 18 formed in the retainer main body 4 so as to open to the bottom wall of the storage space 8.

The diameter of the positioning pin 17 is large enough to fit into the positioning recess 9e in the circumferential direction of the punch 3 without play. As shown in FIG. 9, the positioning recess 9 e forms a gap L on the axis side of the punch 3 with respect to the positioning pin 17 in a predetermined assembled state as shown in FIGS. 1, 2, and 16. Is to have.
More specifically, the inner surface at the back of the positioning recess 9e is formed in an arc shape centered on the center O1, but in a predetermined assembled state, the center of the positioning pin 17 is closer to O1 than to the center O2. Is set to a position slightly offset toward the axis of the punch 3.

Referring to FIG. 10 to FIG.
This will be described with reference to FIG. First, the base end of the select bar 13 is positioned rearward from its upper part, that is, the cylinder device 1.
A protrusion 13b protruding toward the fifth side is formed, and a connection hole 21 extending in the punch axis direction is formed on the protrusion 13b. On the other hand, the drive shaft 15 of the cylinder device 15
The screw portion 22a of the connecting member 22 is screwed into the distal end surface. A mounting hole 23 extending in the axial direction of the punch is formed at the distal end of the connecting member 22, and the lower end of the connecting pin 24 is fixed to the mounting hole 23 by press fitting or the like. The upper end of the connecting pin 24 is loosely fitted into the connecting hole 21 formed in the select bar 13 (see FIG. 15). Thus, when the backing plate 5 is detached from the retainer main body 4, the select bar 13 can be removed from the retainer main body 4 by being displaced upward so as to be pulled out from the connecting pin 24. (See the dash-dot line in FIG. 16).

In the assembled state shown in FIG. 1, the drive shaft 15a of the cylinder device 15 is advanced and
Is advanced to the back surface of the large-diameter head 3b of the punch 3, so that the punch 3 is set to a punchable position where the protruding length of the punch 3 from the retainer 2 is increased. When the select device 13 is retracted from the rear surface of the large-diameter head 3b of the punch 3 by reducing the length of the cylinder device 15 from the state of FIG. 1 (see FIG. 16 for the retract position of the select bar 13), the punch 3 As a result, the displacement upward, that is, the protruding length from the retainer 2 is shortened, and the punching is disabled.

In the non-punching position as shown in FIG. 16, the select bar 13 is retracted from the extended locus of the large-diameter head 3c of the punch 3, but is positioned within the extended locus of the spring seat member 10. To be. That is, when the retainer 2 is removed from the upper mold 1 and the backing plate 5 is removed from the retainer main body 4, and the punch 3 and the spring seat member 9 are pulled upward from the retainer main body 4, the selection bar 13 is left as it is. , The spring seat member 9 interferes. However, by removing the select bar 13 upward as shown by the dashed line in FIG. 16, the punch 3 can be pulled upward together with the spring seat member 9 from the retainer main body 4 without being disturbed by the select bar 13. Become. In addition, select bar 1
The retracted position of the select bar 3 can be moved backward sufficiently to a position where it does not interfere with the spring seat member 9, but in this case, the required displacement of the select bar 13 increases, that is, the cylinder device 15 However, the length becomes large in the axial direction, and the length in the left-right direction in FIG. 1 increases.

In order to assemble the punch 3 with the retainer 2 and attach it to the upper mold 1, first, the spring seat member 9 is placed on the punch 3 in a state where the flat surface portions 3d and 9d are aligned (contact). Prepare the fitted one. The punch 3 with the spring seat member 9 fitted into the retainer body 4 from which the backing plate 5 and the select bar 13 have been removed from the state shown in FIG. Insert. As the fitting of the punch 3 into the guide hole 7 progresses, the spring seat member 9 eventually receives a biasing force from the spring 11, and the positioning recess 9e is fitted to the positioning pin 17. . At this time, by the setting of the gap L shown in FIG. 9, the positioning concave portion 9e and the positioning pin 17 are smoothly fitted.

Thereafter, the select bar 13 is positioned in the guide groove 12 while the connection hole 21 is fitted to the connection pin 24. Thereafter, the backing plate 5 may be fixed to the retainer main body 4, and then the retainer main body 4 may be fixed to the upper mold 1. The removal of the punch 3 from the retainer 2 may be performed in a procedure reverse to that described above.

Here, when the cylinder device 15 presses the select bar 13 toward the punchable position, a greater force is required than when the select bar 13 is retracted toward the non-punchable position. In order to prevent a large force when selecting the punchable position from being applied to the connecting pin 24, for example, the connecting hole 21 formed in the select bar 13 is made longer than the diameter of the connecting pin 24. When the selection bar 13 is set slightly larger in the direction (the larger dimension is indicated by reference numeral L2 in FIG. 15) and the select bar 13 is pressed toward the punchable position, the select bar 13 is directly pressed by the connecting member 22. It is preferable that the pressing force is not applied to the connecting pin 24 toward the punchable position. For this reason, the connecting member 2
2 so that the front end portion can advance below the connection hole 21.
Below the projection 13b where the connection hole 21 is formed,
An escape space 25 in which the distal end of the connecting member 22 is located is formed.

FIGS. 17 to 19 show another method of connecting the select bar 13 and the cylinder device 15. The same components as those shown in FIGS. 1 to 16 are denoted by the same reference numerals. is there. That is, the connecting mechanism 14 has a connecting member 32 fixed to the drive shaft 15a of the cylinder device 15, and the connecting member 32 and the rear end of the select bar 13 are connected via a connecting pin 34 extending in a substantially horizontal direction. , Ie, the select bar 13 is connected to be swingable in the vertical direction. Thus, by swinging the select bar 13 at its retreat stroke end so that the distal end thereof is directed upward around the connecting pin 34, the punch 3 can be moved without being disturbed by the select bar 13. It can be removed from the retainer body 4 together with the spring seat member 9.

The connecting portion between the connecting member 32 and the select bar 13 will be described in more detail.
At the rear end, a pair of left and right bifurcated projections 36 and 37 are formed so as to form a clearance space 35 between them. The tip of the member 32 is located. And the connecting member 3
The connection pin 34 penetrates the connection hole 38 formed at the tip end of the connector 2, and each end of the connection pin 34 is connected to each of the protrusions 36 and 37.
And is fitted in the mounting hole 39. Preferably, the connecting pin 34 has a slight gap in the longitudinal direction of the select bar 13 with respect to the connecting hole 38 of the connecting member 32 so that the pressing force from the cylinder device 15 toward the punchable position is reduced. The transmission is made directly from the connecting member 32 to the select bar 13 without passing through the connecting pin 34 (see FIG. 19).

The return spring 11 is shown in FIG.
In FIG. 16, only the lower end portion is a large-diameter portion which is tightly fitted into the storage recess 10, while the other portion is a small-diameter portion having a sufficiently smaller diameter than the spring storage recess 10. By doing so, it is possible to prevent the spring 11 from accidentally falling off the retainer 2 when the punch 3 is replaced or the like. In FIG. 2, reference numeral 41 denotes a mounting hole for a positioning pin for positioning the retainer 2 (the retainer main body 4) with respect to the upper die 1, and reference numeral 42 fixes the retainer 2 (the retainer main body 4) to the upper die 1. Reference numeral 43 denotes a bolt hole for fixing the backing plate 5 to the retainer body 4.

Although the embodiment has been described above, the present invention is not limited to this and includes, for example, the following case. The select bar 13 can be of a rotary type instead of a reciprocating type. The positioning of the punch 3 in the circumferential direction with respect to the retainer 2 can be performed by forming a projection on the spring seat member 9 (preferably, the projection is formed integrally with the spring seat member 9), The projection may be formed by forming a concave portion in which the projection is fitted from the punch axis direction. When the positioning recess is directly formed in the retainer 2, it is not preferable because the inner surface is processed. Therefore, it is also possible to separately provide a positioning member in which the positioning recess is formed and fix the positioning member to the retainer 2. Good.

The positioning projections and depressions can be set at appropriate positions in the circumferential direction of the punch 3. However, the positioning projections and depressions should be arranged so as not to hinder the movement of the reciprocating select bar 13.
It is preferable to set the position on the opposite side to the retreating direction of the select bar 13 with the axis of the punch 3 interposed therebetween. Similarly, the second portion 9 b projecting upward from the spring seat member 9, that is, each flat surface portion 3 d, 9 d, is set at a position opposite to the retreating direction of the select bar 13 across the axis of the punch 3. Is preferred.

The select bar 13 may be driven manually without using a separate actuator. When the positioning of the punch with respect to the retainer in the circumferential direction is required, the cross-sectional shape of the punched portion is not limited to the irregular shape, and may be a circular shape. The purpose of the present invention is not limited to what is explicitly specified, but also implicitly includes providing what is described as substantially preferred or advantageous.

[Brief description of the drawings]

FIG. 1 shows one embodiment of the present invention, and is a side sectional view when a punch is at a punchable position.

FIG. 2 is a top view when the backing plate is removed from the state of FIG.

FIG. 3 is a top view of an essential part when the select bar, the punch, and the spring seat member are removed from the state of FIG. 2;

FIG. 4 is a right side view of FIG. 5, showing an example of a punch in which a cross-sectional shape of a punched portion is an irregular shape.

FIG. 5 is a right side view of FIG. 4;

FIG. 6 is a top view of FIG. 4;

FIG. 7 is a plan view of a spring seat member.

FIG. 8 is a side view of a spring seat member.

FIG. 9 is an enlarged plan view showing a fitting state of a positioning pin and a positioning recess formed in a spring seat member.

FIG. 10 is a partial cross-sectional side view of a select bar.

FIG. 11 is a bottom view of FIG. 10;

FIG. 12 is a right side view of FIG. 10;

FIG. 13 is a plan view of a connecting member.

FIG. 14 is an exploded partial cross-sectional view showing a connection relationship between a connection member, a connection pin, and a select bar.

FIG. 15 is a partial cross-sectional side view showing a connection relationship between a connection member, a connection pin, and a select bar.

FIG. 16 is a side cross-sectional view showing a state when the select bar is at the retreat position and removing the select bar from the retainer.

FIG. 17 is a partial cross-sectional side view showing another connection relationship between the select bar and the cylinder device.

18 is a partial cross-sectional plan view of FIG.

FIG. 19 is an enlarged partial cross-sectional side view showing in detail a state where the select bar is pressed toward the advanced position by the connecting member in FIGS. 17 and 18.

[Description of sign]

 1: Upper die 2: Retainer 3: Punch 3a: Intermediate shaft portion 3b: Punched portion 3c: Large diameter head 3d: First flat surface portion 4: Retainer body 5: Backing plate 6: Side plate 7 : Guide hole 8: storage space 9: spring seat member 9 a: first portion 9 b: second portion 9 c: through hole 9 d: second flat surface portion 9 e: positioning concave portion 11: return spring 12: guide groove 13: select Bar 17: Positioning pin (positioning projection) 18: Mounting hole

Claims (11)

[Claims] A punch is slidably held in an axial direction by a retainer mounted on a press die, and is directed toward a non-punchable position where a length of projection from the retainer is shortened by a spring. By being biased and changing the length of the punch projecting from the retainer with the select bar located on the base end side of the punch,
In a punch holding device for a press die which switches between a punchable position and a non-punchable position, a punch is fitted to an intermediate shaft portion of a punch and formed at a base end portion of the punch. A spring seat member is provided which is retained by a radial head and on which one end of the spring is seated. A first flat surface portion for positioning is formed by partially chamfering a side surface of the large diameter head. A second portion that contacts the first flat surface portion to regulate the relative rotation between the spring seat member and the punch to position the punch and the spring seat member in the circumferential direction. A flat surface portion is formed, a positioning convex portion is formed on one of the retainer and the spring seat member, and a positioning concave portion is formed on the other, and the positioning convex portion and the positioning concave portion are aligned with the axis of the punch. From the direction It is fitted to have a circumferential positioning of the spring seat member is carried out with respect to the retainer, punch holding apparatus in a press mold, characterized in that. 2. The positioning projection according to claim 1, wherein the positioning projection is constituted by a positioning pin fixed to the retainer so as to extend in parallel with the axis of the punch, and the positioning recess is formed by the spring seat member. A punch holding device in a press die, comprising a notch formed in a side surface of a press die. 3. The positioning device according to claim 2, wherein the notch serving as the positioning recess is fitted on the positioning pin in a predetermined assembled state, and the positioning pin is located closer to the axis of the punch than the positioning pin. A punch holding device in a press die, wherein the punch holding device is formed so as to have a gap between the pin and a pin. 4. The punch according to claim 1, wherein the spring seat member is intermediately fitted around the large-diameter head portion of an intermediate shaft portion of the punch, and the first flat surface portion and the second flat surface portion are connected to each other. The punch holding in the press die, wherein even when the flat surface portion is not engaged, the spring seat member is not displaced in the circumferential direction and the axial direction direction with respect to the punch by a small external force. apparatus. 5. The punch according to claim 1, wherein the select bar is held so as to reciprocate substantially in a diametrical direction of the punch with respect to the retainer, and the select bar advances toward a base end surface of the punch. Sometimes, the punchable position is set, and the select bar is set to be the non-punchable position when the select bar is retracted from the base end surface side of the punch. A punch holding device for a press die, wherein the punch holding device is set so as to be located on a side opposite to a retreating direction of the select bar with respect to an axis of the punch. 6. The punch holding device according to claim 1, wherein each of the flat surface portions is formed so as to be parallel to an axial direction of the punch. 7. The first portion according to claim 1, wherein the spring seat member has a through hole through which the punch penetrates, and a first portion in which a large diameter head of the punch is seated. 1
A second portion protruding toward the large-diameter head side of the punch from an upper surface of one side of the portion, wherein the second flat surface portion is formed on a side surface of the second portion on the side of the through hole. A punch holding device for a press die. 8. The spring seat member according to claim 7, wherein the one side plate surface of the metal plate having a thickness corresponding to the second portion is partially shaved to thereby provide a thickness corresponding to the first portion. A punch holding device for a press die, wherein a cut portion is formed, and the second flat surface portion is formed at the same time as the shaving process. 9. A press die in which a punch is held by a retainer attached to the press die, wherein a positioning recess is formed as a notch on a side surface of a large-diameter head formed at a base end of the punch. A press die, wherein a positioning pin for fixing the punch in the circumferential direction with respect to the retainer is fixed to the retainer, the positioning concave portion being fitted from the axial direction of the punch. 10. The positioning recess according to claim 9, wherein the positioning recess is fitted between the positioning pin and the positioning pin at a position closer to the axis of the punch than the positioning pin in a predetermined assembled state. A press die formed so as to have a gap. 11. The method according to claim 1, wherein
3. The press die according to claim 1, wherein the punched portion formed at the tip of the punch has an irregular cross section.