Punch and press die

Abstract

To provide a punch which can inhibit ejector pins from coming off from housing holes.SOLUTION: A punch 30 includes: a punch body 40 having housing holes 41 which are open toward a die; ejector pins 50 which are respectively housed in the housing holes 41 and eject scraps from an apical surface of the punch body 40; and biasing members 70 each of which constantly biases the ejector pin 50. The ejector pin 50 includes: an ejection part 51; a flange part 52; and an intermediate part 53. The housing hole 41 has: a regulation surface 45 which regulates a protruding length of the ejector pin 50 from the punch body 40; and a seating surface 46 which faces the intermediate part 53 through a gap in an ejecting direction when the flange part 52 and the regulation surface 45 contact with each other.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a punch and a press die. [Background technology]

[0002] Patent Document 1 discloses, as a prior art of the invention described in Patent Document 1, a jector punch including a punch body having a through hole and a jector pin disposed inside the through hole. The jector pin is configured to be able to protrude and retract from the tip face of the punch body.

[0003] The through hole has a small hole portion that opens to the tip surface of the punch body and a large hole portion that is continuous with the small hole portion. The ejector pin has a long shank and a flange portion that is continuous with the end of the shank. The shank is slidably housed in the small hole portion. The flange portion is housed in the large hole portion. The flange portion prevents the ejector pin from coming out of the punch body.

[0004] A coil spring is provided inside the large hole portion to bias the jector pin so as to protrude from the tip surface of the punch body. The coil spring is disposed between the screw screwed into the large hole portion and the jector pin. The jector pin retracts into the punch body against the biasing force of the coil spring while the punch body is punching the workpiece, but protrudes from the punch body when punching of the workpiece is completed. This causes scrap punched out of the workpiece to be pulled away from the punch body, thereby suppressing scrap lift-up. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2007-7686 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, when a jector punch is used, not only does the shank come into contact with the workpiece, but the flange of the jector pin also comes into contact with the inner surface of the through hole, so that repeated stress is likely to act on the boundary between the shank and the flange, which may result in the boundary between the shank and the flange breaking, causing the jector pin to come out of the punch body. [Means for solving the problem]

[0007] A punch for solving the above problem includes a punch body having an accommodation hole that opens toward a die and punching out a workpiece in cooperation with the die, an ejector pin that is accommodated in the accommodation hole and configured to be able to protrude into and retract from a tip end surface of the punch body and ejects scrap punched out of the workpiece by the punch body from the tip end surface of the punch body, and a biasing member that is accommodated in the accommodation hole and constantly biases the ejector pin in a direction in which the ejector pin is ejected, and the ejector pin is configured to eject the scrap from the workpiece by the punch body. the accommodating hole has a regulating surface that regulates the amount of protrusion of the ejector pin from the punch body when the flange contacts the ejection direction, and a seating surface that comes into contact with the intermediate portion from the ejection direction or faces the intermediate portion across a gap in the ejection direction when the flange contacts the regulating surface.

[0008] According to the above-mentioned configuration, even if the boundary between the intermediate portion and the flange portion breaks during use of the punch, the intermediate portion can be prevented from moving beyond the seat surface in the ejection direction of the ejector pin, and therefore the ejector pin can be prevented from coming out of the accommodation hole.

[0009] According to the above configuration, even if the boundary portion is broken, the ejector pin is biased in the discharging direction by the biasing member via the separated flange portion, so that even if the boundary portion is broken, the ejector pin's function of discharging scrap can be prevented from being impaired, and the punch can be used continuously. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view showing a press die according to one embodiment. [Diagram 2] FIG. 2 is an enlarged cross-sectional view of the punch in FIG. 1, focusing on an ejector pin. [Diagram 3] FIG. 3 is an enlarged cross-sectional view centered on the first corner portion in FIG. [Figure 4] FIG. 4 is an enlarged cross-sectional view centered on the second corner portion in FIG. [Diagram 5] FIG. 5 is a cross-sectional view showing a state in which the ejector pin of FIG. 1 is retracted inside the punch body. [Figure 6] FIG. 6 is a cross-sectional view showing a state in which the ejector pin of FIG. 1 ejects scrap. [Figure 7] FIG. 7 is a cross-sectional view showing a state in which the boundary between the middle portion and the flange portion of the ejector pin in FIG. 1 is broken. [Figure 8] FIG. 8 is a cross-sectional view showing a state in which the ejector pin of FIG. 1 is in contact with the curved intended portion. [Figure 9] FIG. 9 is a cross-sectional view showing a modified ejector pin. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, one embodiment of a punch and a press die will be described with reference to FIGS. (Press mold 10) 1, the press die 10 is a die for punching out a thin plate-like workpiece W. The press die 10 includes a die 20, a punch 30, and a stripper plate 80.

[0012] (Die 20) The die 20 is in the shape of a block having a mounting surface on which the workpiece W is placed. The die 20 has a die hole 21 that opens to the mounting surface and passes through the die 20.

[0013] (Punch 30) The punch 30 includes a punch body 40, a plurality of ejector pins 50, a plurality of fixing members 60, and a plurality of biasing members 70.

[0014] (Punch body 40) The punch body 40 has a columnar shape. The punch body 40 cooperates with the die 20 to punch out the workpiece W. The punch body 40 has a plurality of accommodating holes 41 that open toward the die 20. Each accommodating hole 41 penetrates the punch body 40 in the axial direction. The plurality of accommodating holes 41 are provided, for example, at intervals from one another in the circumferential direction around the central axis of the punch body 40.

[0015] (Ejector pin 50) Each ejector pin 50 has a columnar shape. The multiple ejector pins 50 are accommodated in the multiple accommodation holes 41, respectively. The ejector pins 50 are configured to be able to protrude and retract from the tip surface of the punch body 40, i.e., the contact surface of the punch body 40 with the workpiece W. The ejector pins 50 eject scrap punched out of the workpiece W by the punch body 40 from the tip surface of the punch body 40, i.e., pull the scrap away from the tip surface of the punch body 40.

[0016] As shown in FIG. 2, the ejector pin 50 has a dispensing portion 51, a flange portion 52, and an intermediate portion 53. The dispensing portion 51 constitutes the lower end portion of the ejector pin 50. The flange portion 52 constitutes the upper end portion of the ejector pin 50. The intermediate portion 53 constitutes the portion of the ejector pin 50 between the dispensing portion 51 and the flange portion 52. The dispensing portion 51, the intermediate portion 53, and the flange portion 52 are formed continuously. The cross-sectional shapes perpendicular to the axial direction of the dispensing portion 51, the intermediate portion 53, and the flange portion 52 are different circles.

[0017] The discharging portion 51 discharges scrap from the tip surface of the punch body 40. The tip of the discharging portion 51 is semispherical. Flange portion 52 protrudes more radially outward than dispensing portion 51. More specifically, flange portion 52 has a larger diameter than dispensing portion 51.

[0018] Intermediate portion 53 protrudes to a position that is more outer circumferential than dispensing portion 51 and more inner circumferential than flange portion 52. More specifically, intermediate portion 53 has a larger diameter than dispensing portion 51 and a smaller diameter than flange portion 52.

[0019] 3, a first corner 54 is formed at the boundary between dispensing portion 51 and intermediate portion 53. First corner 54 is formed by the outer circumferential surface of dispensing portion 51 and the lower surface of intermediate portion 53. The cross-sectional shape of first corner 54 perpendicular to the circumferential direction of ejector pin 50 is an arc shape that protrudes inward from ejector pin 50.

[0020] 4, a second corner 55 is formed at the boundary between the intermediate portion 53 and the flange portion 52. The second corner 55 is formed by the outer circumferential surface of the intermediate portion 53 and the lower surface of the flange portion 52. The cross-sectional shape of the second corner 55 perpendicular to the circumferential direction of the ejector pin 50 is an arc shape that protrudes inwardly of the ejector pin 50. The radius of curvature of the second corner 55 is smaller than the radius of curvature of the first corner 54.

[0021] At the boundary between the intermediate portion 53 and the flange portion 52, there is provided a weak portion 56 which is weaker than the boundary between the dispensing portion 51 and the intermediate portion 53. When tensile stress, bending stress, or the like acts on the ejector pin 50, the weak portion 56 functions as a portion where the degree of stress concentration is greater than that at the boundary between the dispensing portion 51 and the intermediate portion 53. The weak portion 56 is constituted by a second corner portion 55 having a radius of curvature smaller than the radius of curvature of the first corner portion 54.

[0022] (Housing Hole 41) As shown in FIG. 2, each of the accommodating holes 41 has a first accommodating portion 42, a second accommodating portion 43, and a third accommodating portion 44. The first accommodating portion 42 opens to the tip end surface of the punch body 40 and slidably accommodates the dispensing portion 51. The second accommodating portion 43 accommodates the intermediate portion 53. The third accommodating portion 44 opens to the base end surface of the punch body 40 and accommodates the flange portion 52. The first accommodating portion 42, the second accommodating portion 43, and the third accommodating portion 44 are formed continuously in this order. The cross-sectional shapes of the first accommodating portion 42, the second accommodating portion 43, and the third accommodating portion 44 perpendicular to the axial direction are different circles. The ejector pin 50 is disposed inside the accommodating hole 41 through the third accommodating portion 44.

[0023] The inner diameter of the first storage section 42 is slightly larger than the diameter of the dispensing section 51 and smaller than the diameter of the intermediate section 53. The inner diameter of the second storage section 43 is larger than the diameter of the intermediate section 53 and smaller than the diameter of the flange section 52. The inner diameter of the third storage section 44 is larger than the diameter of the flange section 52.

[0024] The gap between the outer peripheral surface of intermediate portion 53 and the inner surface of second storage portion 43 is larger than the gap between the outer peripheral surface of dispensing portion 51 and the inner surface of first storage portion 42. The gap between the outer peripheral surface of flange portion 52 and the inner surface of third storage portion 44 is larger than the gap between the outer peripheral surface of dispensing portion 51 and the inner surface of first storage portion 42. In order to avoid contact between the outer peripheral surface of flange portion 52 and the inner surface of third storage portion 44, it is preferable that the size of the gap between the outer peripheral surface of flange portion 52 and the inner surface of third storage portion 44 is equal to or larger than the size of the gap between the outer peripheral surface of intermediate portion 53 and the inner surface of second storage portion 43.

[0025] 4, the accommodating hole 41 has a regulating surface 45. The regulating surface 45 connects the inner surface of the second accommodating portion 43 and the inner surface of the third accommodating portion 44. The regulating surface 45 includes a plane perpendicular to the axial direction of the punch body 40. The regulating surface 45 regulates the amount of protrusion of the ejector pin 50 from the punch body 40 by contacting the flange portion 52 from the ejection direction of the ejector pin 50.

[0026] 3, the accommodation hole 41 has a seat 46. The seat 46 connects the inner surface of the first accommodation portion 42 and the inner surface of the second accommodation portion 43. The seat 46 includes a plane perpendicular to the axial direction of the punch body 40. The seat 46 faces the middle portion 53 with a gap therebetween in the ejection direction of the ejector pin 50 when the flange portion 52 and the regulating surface 45 come into contact with each other.

[0027] (Fixing member 60) 1, the multiple fixing members 60 are respectively accommodated in the multiple accommodating holes 41. Each fixing member 60 is, for example, a flat head screw. The fixing member 60 is fixed to the punch body 40 by being screwed into an upper portion of the third accommodating portion 44.

[0028] (biasing member 70) The multiple urging members 70 are respectively housed in the multiple housing holes 41. The urging members 70 are disposed between the ejector pins 50 and the fixed member 60 in the third housing portion 44. The urging members 70 constantly urge the ejector pins 50 in the ejection direction of the ejector pins 50. Each of the urging members 70 is, for example, a compression coil spring.

[0029] (Stripper plate 80) The stripper plate 80 is constantly biased toward the die 20 by a spring (not shown). The stripper plate 80 presses the workpiece W against the die 20 when punching the workpiece W. The stripper plate 80 has a through hole 81 into which the punch 30 is inserted.

[0030] The operation of this embodiment will be described. 5, when punching the workpiece W, the punch 30 and the stripper plate 80 descend toward the die 20. The stripper plate 80 comes into contact with the workpiece W, thereby pressing the workpiece W against the die 20. Thereafter, the punch 30 descends with the stripper plate 80 pressing the workpiece W against the die 20. As the punch 30 descends, the ejector pins 50 protruding from the punch body 40 come into contact with the workpiece W, and the ejector pins 50 retreat into the punch body 40 against the biasing force of the biasing member 70. Thereafter, the tip surface of the punch body 40 comes into contact with the workpiece W.

[0031] 6, as the punch 30 further descends, the workpiece W is punched out by the die 20 and the punch 30. Each ejector pin 50 is constantly biased in the ejection direction of the ejector pin 50 by the biasing member 70. Therefore, the scrap punched out from the workpiece W is ejected from the tip surface of the punch body 40 by each ejector pin 50 protruding from the punch body 40.

[0032] Incidentally, when the punch 30 is used, the flange portion 52 and the inner surface of the receiving hole 41 are repeatedly brought into contact with each other, so that stress is repeatedly applied to the boundary portion between the intermediate portion 53 and the flange portion 52 . 7, repeated stress may be applied to the boundary between intermediate portion 53 and flange portion 52, which may cause the boundary between intermediate portion 53 and flange portion 52 to break. According to punch 30 of the present embodiment, even if the boundary between intermediate portion 53 and flange portion 52 breaks during use of punch 30, it is possible to prevent intermediate portion 53 from moving beyond seat surface 46 in the ejection direction of ejector pin 50.

[0033] The effects of this embodiment will be described. (1) The punch 30 includes a punch body 40 having a housing hole 41 that opens toward the die 20, an ejector pin 50 that is housed in the housing hole 41 and ejects scrap from the tip surface of the punch body 40, and a biasing member 70 that constantly biases the ejector pin 50. The ejector pin 50 has a discharging portion 51, a flange portion 52, and an intermediate portion 53. The housing hole 41 has a regulating surface 45 that regulates the amount of protrusion of the ejector pin 50 from the punch body 40, and a seating surface 46 that faces the intermediate portion 53 with a gap therebetween in the discharging direction when the flange portion 52 and the regulating surface 45 come into contact with each other.

[0034] According to the above configuration, even if the boundary between the intermediate portion 53 and the flange portion 52 is broken, the ejector pin 50 can be prevented from coming out of the receiving hole 41. Furthermore, according to the above configuration, even if the boundary portion is broken, the ejector pin 50 is biased in the discharging direction by the biasing member 70 via the separated flange portion 52. As a result, even if the boundary portion is broken, the function of the ejector pin 50 to discharge scrap can be prevented from being impaired, so that the punch 30 can be used continuously.

[0035] Therefore, for example, even if the ejector pin 50 breaks, the use of the press die 10 can be continued, and the ejector pin 50 can be replaced when the press die 10 is stopped. (2) When the flange portion 52 and the regulating surface 45 come into contact with each other, the middle portion 53 faces the seat surface 46 with a gap therebetween in the dispensing direction.

[0036] According to the above configuration, when the ejector pin 50 protrudes from the punch body 40, the flange portion 52 is in contact with the restriction surface 45, while the middle portion 53 is not in contact with the seat surface 46. This makes it difficult for stress to act on the boundary portion between the dispensing portion 51 and the middle portion 53 when the punch 30 is in use. This makes it possible to prevent the ejector pin 50 from coming out of the accommodation hole 41 due to breakage of the boundary portion between the dispensing portion 51 and the middle portion 53.

[0037] (3) The gap between the outer surface of the intermediate portion 53 and the inner surface of the second storage portion 43, and the gap between the outer surface of the flange portion 52 and the inner surface of the third storage portion 44 are larger than the gap between the outer surface of the dispensing portion 51 and the inner surface of the first storage portion 42.

[0038] According to the above configuration, the ejection portion 51 slides against the inner surface of the first housing portion 42, thereby suppressing misalignment of the ejector pin 50 with respect to the punch body 40. In addition, it is possible to suppress the outer surface of the intermediate portion 53 from contacting the inner surface of the second housing portion 43 and the outer surface of the flange portion 52 from contacting the inner surface of the third housing portion 44. As a result, when the punch 30 is used, stress is less likely to act on the boundary portion between the intermediate portion 53 and the flange portion 52, thereby suppressing breakage of the boundary portion.

[0039] (4) At the boundary between intermediate portion 53 and flange portion 52, weak portion 56 that is weaker than the boundary between dispensing portion 51 and intermediate portion 53 is provided. According to the above configuration, if the ejector pin 50 breaks during use of the punch 30, the boundary between the middle portion 53 and the flange portion 52 is more likely to break than the boundary between the dispensing portion 51 and the middle portion 53. Therefore, the ejector pin 50 can be prevented from coming out of the accommodation hole 41.

[0040] (5) The weakened portion 56 is formed by the second corner portion 55 having a radius of curvature smaller than the radius of curvature of the first corner portion 54 . According to the above configuration, since the first corner portion 54 and the second corner portion 55 have an arc-shaped cross section, the degree of stress concentration at each corner can be reduced. This makes it possible to prevent the boundary portion between the dispensing portion 51 and the intermediate portion 53, and the boundary portion between the intermediate portion 53 and the flange portion 52 from breaking.

[0041] In addition, the radius of curvature of the second corner 55 constituting the fragile portion 56 is smaller than the radius of curvature of the first corner 54. As a result, the degree of stress concentration at the second corner 55 is likely to be greater than the degree of stress concentration at the first corner 54. Therefore, while fracture of the above-mentioned boundary portion is suppressed, if fracture does occur, the boundary portion between the middle portion 53 and the flange portion 52 is more likely to fracture than the boundary portion between the dispensing portion 51 and the middle portion 53. Therefore, it is possible to suppress the ejector pin 50 from coming out of the accommodation hole 41.

[0042] (6) The punch 30 is equipped with a plurality of ejector pins 50. As shown in FIG. 8, the portion of the workpiece W to be punched by the punch 30 and the die 20 (hereinafter referred to as the planned portion Wp) may be deformed so as to be curved in a direction away from the punch 30 as the punch 30 descends. This deformation occurs when bending stress acts on the planned portion Wp due to the clearance between the inner surface of the die hole 21 and the outer surface of the punch body 40 when the planned portion Wp is about to be sheared by the die 20 and the punch 30. When such deformation occurs, the portion of the planned portion Wp that the ejector pin 50 contacts during punching of the workpiece W becomes inclined with respect to the ejector pin 50. As a result, the ejector pin 50 that has temporarily retreated inside the punch body 40 protrudes from the punch body 40 again before punching of the workpiece W is completed. At this time, the ejector pin 50 comes into contact with the curved portion of the planned portion Wp, so that bending stress acts on the ejector pin 50. For this reason, the stress acting on the boundary between the intermediate portion 53 and the flange portion 52 is likely to be large. This phenomenon is likely to become more pronounced as the ejector pin 50 is positioned closer to the outer periphery of the punch body 40. This is because the contact angle between the curved portion of the planned portion Wp and the ejector pin 50 is likely to become larger as the ejector pin 50 is positioned closer to the outer periphery of the punch body 40.

[0043] In this regard, according to the above configuration, even if the boundary between the intermediate portion 53 and the flange portion 52 breaks due to the bending stress, the ejector pin 50 can be prevented from coming out of the accommodation hole 41.

[0044] (7) The press mold 10 includes a die 20 and a punch 30 . According to the above configuration, it is possible to achieve effects similar to the above-mentioned effects (1) to (6). <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction.

[0045] A cross-sectional shape perpendicular to the axial direction of at least one of the components of the dispensing section 51, the intermediate section 53, and the flange section 52 may be polygonal. In this case, a cross-sectional shape perpendicular to the axial direction of at least one of the components of the first storage section 42, the second storage section 43, and the third storage section 44 may be polygonal.

[0046] The tip of the dispensing part 51 does not have to be hemispherical, and may have, for example, a flat surface facing the workpiece W. In this case, the cross-sectional shape and size of the dispensing part 51 perpendicular to the axial direction may be constant in the axial direction.

[0047] The punch 30 may be equipped with a single ejector pin 50. As shown in FIG. 9, the fragile portion 56 may be constituted by a constricted portion 57 formed at the connection portion of the intermediate portion 53 with the flange portion 52 .

[0048] The cross-sectional shape of second corner portion 55 does not have to be circular. Second corner portion 55 may be formed by the outer circumferential surface of intermediate portion 53 and the underside of flange portion 52, which intersect at a right angle. In this case, as long as first corner portion 54 has a circular cross-sectional shape, fragile portion 56 may be formed by second corner portion 55 described above.

[0049] The ejector pin 50 does not have to be provided with the fragile portion 56. In this case, the first corner 54 may be formed by the outer circumferential surface of the dispensing portion 51 and the lower surface of the intermediate portion 53, which intersect at a right angle, and the second corner 55 may be formed by the outer circumferential surface of the intermediate portion 53 and the lower surface of the flange portion 52, which intersect at a right angle.

[0050] The dispensing portion 51, the intermediate portion 53, and the flange portion 52 do not have to be formed continuously. In other words, a portion having a different shape from the dispensing portion 51 and the intermediate portion 53 or between the intermediate portion 53 and the flange portion 52 may be formed at least either between the dispensing portion 51 and the intermediate portion 53 or between the intermediate portion 53 and the flange portion 52.

[0051] The second storage section 43 may slidably store the intermediate section 53. In this case, the gap between the outer circumferential surface of the flange section 52 and the inner surface of the third storage section 44 and the gap between the outer circumferential surface of the dispensing section 51 and the inner surface of the first storage section 42 may be larger than the gap between the outer circumferential surface of the intermediate section 53 and the inner surface of the second storage section 43.

[0052] When the flange portion 52 and the regulating surface 45 come into contact with each other, the intermediate portion 53 may come into contact with the seating surface 46 from the ejection direction of the ejector pin 50. That is, each time the ejector pin 50 protrudes from the punch body 40, the flange portion 52 may come into contact with the regulating surface 45 and the intermediate portion 53 may come into contact with the seating surface 46.

[0053] The restricting surface 45 and the seating surface 46 may be formed by a member separate from the punch body 40 arranged inside the accommodating hole 41. For example, annular members each constituting the restricting surface 45 and the seating surface 46 and having different inner diameters may be arranged inside the accommodating hole 41. Also, for example, stoppers each constituting the restricting surface 45 and the seating surface 46 may be arranged inside the accommodating hole 41 through a communication hole that communicates between the inside and the outside of the accommodating hole 41. In these cases, at least two of the first accommodating portion 42, the second accommodating portion 43, and the third accommodating portion 44 may have the same inner diameter.

[0054] The above embodiment includes the configurations described in the following supplementary notes. [Appendix 1] A punch comprising: a punch body having an accommodation hole that opens toward a die and that punches out a workpiece in cooperation with the die; an ejector pin that is accommodated in the accommodation hole and is configured to be able to protrude into and retract from a tip end surface of the punch body and that ejects scrap punched out of the workpiece by the punch body from the tip end surface of the punch body; and a biasing member that is accommodated in the accommodation hole and that constantly biases the ejector pin in an ejection direction of the ejector pin, wherein the ejector pin serves as an ejection member for ejecting the scrap. the accommodating hole has a regulating surface with which the flange portion comes into contact in the dispensing direction to regulate an amount of protrusion of the ejector pin from the punch body, and a seating surface with which the intermediate portion comes into contact from the dispensing direction or which faces the intermediate portion with a gap therebetween when the flange portion comes into contact with the regulating surface.

[0055] [Appendix 2] A punch as described in [Appendix 1], wherein when the flange portion and the regulating surface come into contact, the intermediate portion faces the seat surface in the dispensing direction via a gap. [Appendix 3] A punch described in [Appendix 1] or [Appendix 2], wherein the accommodating hole has a first accommodating portion that slidably accommodates the dispensing portion, a second accommodating portion that accommodates the intermediate portion, and a third accommodating portion that accommodates the flange portion, and the gap between the outer surface of the intermediate portion and the inner surface of the second accommodating portion, and the gap between the outer surface of the flange portion and the inner surface of the third accommodating portion are larger than the gap between the outer surface of the dispensing portion and the inner surface of the first accommodating portion.

[0056] [Appendix 4] A punch described in any one of [Appendix 1] to [Appendix 3], wherein the dispensing portion, the intermediate portion, and the flange portion are formed continuously, and a weak portion is provided at the boundary between the intermediate portion and the flange portion which is weaker than the boundary between the dispensing portion and the intermediate portion.

[0057] [Appendix 5] The punch described in [Appendix 4], wherein a first corner portion having an arc-shaped cross section is formed at the boundary between the dispensing portion and the intermediate portion by two intersecting outer surfaces of the dispensing portion and the intermediate portion, and a second corner portion having an arc-shaped cross section is formed at the boundary between the intermediate portion and the flange portion by two intersecting outer surfaces of the intermediate portion and the flange portion, and the weak portion is constituted by the second corner portion having a radius of curvature smaller than the radius of curvature of the first corner portion.

[0058] [Appendix 6] A punch described in any one of [Appendix 1] to [Appendix 5], comprising a plurality of the ejector pins and a plurality of the biasing members which constantly bias each of the plurality of ejector pins in the dispensing direction, and the punch body has a plurality of the accommodating holes which accommodate each of the plurality of ejector pins.

[0059] [Appendix 7] A press die comprising the die and the punch according to any one of [Appendix 1] to [Appendix 6]. [Explanation of symbols]

[0060] W…Work Wp…Planning section 10... Press mold 20…Die 21…Die hole 30...Punch 40…Punch body 41...Housing hole 42…First storage section 43…Second storage section 44…Third storage section 45. Regulatory aspects 46…Seat 50...Ejector pin 51...Payment section 52…Flange 53…Middle section 54…First corner 55…Second corner 56…Weakened part 57…Constriction 60…Fixing member 70... Urging member 80...Stripper plate 81...Through hole

Claims

1. A punch body having an accommodation hole that opens toward a die and punches out a workpiece in cooperation with the die; an ejector pin that is accommodated in the accommodation hole and is configured to be able to protrude into and retract from a tip end surface of the punch body, and that ejects scrap punched out of the work by the punch body from the tip end surface of the punch body; a biasing member that is accommodated in the accommodation hole and constantly biases the ejector pin in a direction in which the ejector pin is ejected, The ejector pin is A discharging unit that discharges the scrap; A flange portion protruding outward from the dispensing portion; A middle portion is a portion between the dispensing portion and the flange portion, and protrudes to a position on the outer periphery side of the dispensing portion and on the inner periphery side of the flange portion, The receiving hole is a restriction surface that restricts a protrusion amount of the ejector pin from the punch body by contacting the flange portion from the dispensing direction; When the flange portion and the regulating surface come into contact with each other, the intermediate portion comes into contact with the regulating surface from the dispensing direction, or the intermediate portion and the seat surface face each other through a gap in the dispensing direction. punch.

2. When the flange portion and the regulating surface come into contact with each other, the intermediate portion faces the seat surface via a gap in the dispensing direction.

2. The punch of claim 1.

3. The storage hole has a first storage portion that slidably stores the dispensing portion, a second storage portion that stores the intermediate portion, and a third storage portion that stores the flange portion, A gap between an outer surface of the intermediate portion and an inner surface of the second storage portion, and a gap between an outer surface of the flange portion and an inner surface of the third storage portion are larger than a gap between an outer surface of the dispensing portion and an inner surface of the first storage portion.

2. The punch of claim 1.

4. The dispensing portion, the intermediate portion, and the flange portion are formed continuously, A weak portion is provided at the boundary between the intermediate portion and the flange portion, which is weaker than the boundary between the dispensing portion and the intermediate portion.

2. The punch of claim 1.

5. A first corner portion having an arc-shaped cross section is formed at the boundary between the dispensing portion and the intermediate portion, a second corner portion having an arc-shaped cross section is formed at a boundary between the intermediate portion and the flange portion, The weakened portion is constituted by the second corner portion having a radius of curvature smaller than the radius of curvature of the first corner portion.

5. The punch according to claim 4.

6. The ejector pins include a plurality of ejector pins and a plurality of biasing members that constantly bias each of the ejector pins toward the dispensing direction, The punch body has a plurality of the accommodating holes for accommodating each of the plurality of ejector pins.

2. The punch of claim 1.

7. The die; The punch according to any one of claims 1 to 6 is provided. Press mold.

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