JP2008080350A - Punch for punching sheet metal, device for punching sheet metal provided with the same punch and method of punching sheet metal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a punch for punching sheet metal with which stress can be concentrated on the sheet metal by the tip of a corner part for stipulating the hole of a die and a through-hole can be formed by tearing off the sheet metal by the corner part for stipulating the hole of the die even when the diameter of the through-hole to be punched is small and the through-hole can be formed in an accurate position in addition there is no burr, a device for punching the sheet metal provided with the same punch and a method of punching the sheet metal. <P>SOLUTION: The device 1 for punching the sheet metal is provided with an upper die holder 2 which is elevated and lowered with a hydraulic ram or the like, a pressing plate 3 which is fixed to the upper die holder 2, a pressing pad 5 which is hung down through an elastic member 4 from the upper die holder 2, a punch holder 7 which is fixed to the pressing pad 5 through a bolt 6 or the like, a lower die 9 on which the sheet metal 8 to be punched is placed and a die 10 which is embedded in the lower die 9. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a punch for punching a thin metal plate, a punching device for a thin metal plate provided with the punch, and a method for drilling a thin metal plate.

JP 2002-153920 A

  A punch having a cylindrical main body having an outer diameter smaller than the hole diameter of the die and a conical protrusion on one end surface of the cylindrical main body is pressed against the thin metal sheet, and a punch hole is formed in the thin metal sheet to open a hole. With the protrusion inserted into the piercing hole restricting the movement of the sheet metal, the punch is further inserted into the hole of the die to break the sheet metal around one end surface of the cylindrical body of the punch so that it is substantially the same as the hole of the die. There has been proposed a drilling device in which a through-hole having a diameter is formed in a thin metal plate (see, for example, Patent Document 1).

  Such a perforating device positions a thin metal plate with a projection, and applies a pulling force mainly to the thin metal plate rather than a shearing force to cut through the thin metal plate at a corner that defines the hole of the die to form a through hole. In order to accurately form a through-hole in a thin metal plate without causing burrs, the outer peripheral edge (corner) of one end of the cylindrical body of the punch is rounded to define the hole of the die. It is preferable to concentrate the stress on the sheet metal at the tip of the corner to be cut, but when the diameter of the through hole to be drilled is small, the result is that a cylindrical body of a punch having a small diameter is used. If the corner of one end surface of the columnar body is rounded in advance, the circular end surface of the columnar body is not formed between the conical protrusion and the corner of the columnar body, and the desired tensile force is applied to the sheet metal. Can no longer be added, conical Situation in the cylindrical body is inserted following while expanded the break through holes can occur breaking through hole formed by force.

  The present invention has been made in view of the above points, and its purpose is to concentrate stress on a sheet metal at the end of a corner that defines the hole of a die even when the diameter of a through hole to be drilled is small. A thin plate that can cut through a thin sheet metal at the corners that define the hole of the die to form a through hole, and thus can form a through hole at an accurate position without burrs. An object of the present invention is to provide a punch for punching a metal, a punching device for a thin metal plate provided with the punch, and a punching method for the thin metal plate.

  A punch for punching a thin metal plate according to the present invention includes a columnar main body, and a columnar protrusion having a conical tip and being integrally provided at the center of one end surface of the main body. And an elastically deformable member that surrounds at least the protruding portion excluding the conical tip and is provided on one end surface of the main body, wherein the elastically deformable member includes the main body and It has a rigidity smaller than that of the thin metal sheet to be perforated and has a cylindrical peripheral surface flush with the cylindrical peripheral surface of the main body.

  The punch according to the present invention first forms a piercing hole in the thin metal plate by the conical tip of the protruding portion, restricts the movement of the thin metal plate by the protruding portion inserted into the piercing hole, and then defines the hole of the die. The stress concentrated on the thin plate metal is generated at the corner tip, and the thin plate metal is shredded and broken at the corner tip to form a through hole in the thin plate metal. In this case, if the stress concentrated on the sheet metal is generated not only at the corner tip of the die but also at the outer peripheral edge (corner portion) of the end face of the main body of the punch, the fracture location becomes indefinite and burrs are likely to occur. However, in the punch according to the present invention, the elastically deformable member provided on one end surface of the main body portion has a rigidity smaller than the rigidity of the main body portion and the thin plate metal to be punched. The outer peripheral edge (corner part) of the elastically deformable member can be elastically deformed to avoid stress concentration of the sheet metal at the outer peripheral edge, and concentrated stress is generated on the sheet metal mainly at the corner end of the die. Moreover, as a result of being able to push the sheet metal at a portion other than the outer peripheral edge of the elastically deformable member that is elastically deformed, the main body portion and the elastically deformable member are inserted into the piercing hole formed by the conical tip of the protruding portion. Break through In this way, it is possible to avoid a situation where the sheet metal is subsequently inserted while expanding the diameter, and to apply a desired tensile force to the sheet metal, thus forming a through hole at an accurate position without a burr. be able to.

  In the punch of the present invention, preferably, the elastically deformable member has an annular surface that is orthogonal to the cylindrical peripheral surface and from which the protruding portion protrudes.

  The elastically deformable member may be fixed to one end face and the protrusion of the columnar main body, but is preferably fixed to one end face of the main body and slidable on the protrusion. The projection is surrounded by

  As the elastically deformable member having rigidity smaller than that of the thin plate metal to be perforated, specifically, synthetic resin such as phenol resin, polyamide (nylon) resin, polyethylene resin, or copper or phosphor bronze, It is formed from a copper alloy such as beryllium copper or a non-ferrous metal such as titanium.

  The method of the present invention in which a through hole is formed in a thin plate metal by a punching device having the above punch and a die having a hole into which such a punch is inserted is a hole that breaks through the thin plate metal by the tip of a protrusion. In cooperation with the die around the peripheral surface of the elastically deformable member compressed by inserting a punch into the die hole in a state where the movement of the sheet metal is restricted by the protrusion inserted into the piercing hole Then, the thin plate metal is broken to form a through hole in the thin plate metal.

  In the method of the present invention, the elastic deformable member is expanded outward by compression of the elastic deformable member, and the sheet metal is broken in cooperation with the die around the peripheral surface of the expanded elastic deformable member. You may make it form a through-hole in a sheet metal.

  The punch is elastically deformed by punching a hole in the sheet metal with the tip of the protrusion, and further inserting the punch into the hole of the die while restricting the movement of the sheet metal with the protrusion inserted into the hole. The present invention is used for a thin plate metal drilling device in which a thin plate metal is broken around a peripheral surface of a possible member to form a through hole in the thin plate metal.

  The sheet metal punching device of the present invention comprises the punch according to any one of the above aspects and a die having a hole into which the punch is inserted, and the sheet metal is somewhat sheared by the punch and the die. In addition to this, a tensile fracture is mainly generated to effectively form a through hole in the thin metal plate.

  The punching device is used to drill a hole in a thin metal sheet by a protrusion, and further insert a punch into the die hole in a state where the movement of the thin metal sheet is restricted by the protrusion inserted into the hole. A thin plate metal is broken around to form a through hole in the thin plate metal.

  The sheet metal drilled by the drilling device of the present invention has a thickness of about 0.4 mm to 2.0 mm in order to obtain good results, but in order to obtain better results, The plate thickness is about 0.6 mm to 1.6 mm.

  The punch of the present invention can be used as a punch unit. The punch unit is mounted on a case, a slider slidably mounted in the vertical direction in the case, and slidably mounted in the slider in the vertical direction. And a return means disposed in the slider and elastically biasing the punch and the slider upward to return the punch and the slider to the initial position. A sliding guide member is further provided on the case so as to guide the vertical movement of the punch.

  The slider is provided with a recess, and is preferably engaged with a retaining pin fixed to the case in the recess so that the slider does not come out of the case due to the elastic force of the return means. The coil spring is preferably provided, but the present invention is not limited to this, and other elastic members may be used.

  In the present invention, the main body, the protrusion, and the elastically deformable member may be cylindrical, quadrangular, elliptical, or the like, and the tip of the protrusion is also conical, pyramidal, elliptical, or the like. The hole of the die is determined corresponding to the main body portion and the elastically deformable member, and thus the through hole to be formed is not limited to a circle, and may be a rectangle, an ellipse, or the like. .

  According to the present invention, even when the diameter of the hole to be drilled is small, stress can be concentrated on the sheet metal at the tip of the corner that defines the hole of the die, and the sheet metal is formed at the corner that defines the hole of the die. A punch for punching a thin metal plate that can be formed by cutting it through to form a through hole, and can be formed at a precise position without a burr, and a thin metal plate provided with the punch In addition, it is possible to provide a perforating apparatus and a method for perforating sheet metal.

  Next, the present invention will be described in more detail based on an example of a preferred embodiment shown in the drawings. The present invention is not limited to these examples.

  1 to 4, the thin plate metal drilling device 1 of this example includes an upper mold holder 2 that is lifted and lowered by a hydraulic ram, a pressing plate 3 fixed to the upper mold holder 2, and an upper mold holder 2. A pressing pad 5 suspended through an elastic member 4, a punch holder 7 configured as a punch unit fixed to the pressing pad 5 with a bolt 6 or the like, and a sheet metal 8 to be punched Is mounted, and a die 10 embedded in the lower mold 9 is provided.

  The punch holder 7 includes a cylindrical case 11 fixed to the pressing pad 5 with a bolt 6 or the like, a cylindrical slider 12 mounted on the case 11 so as to be slidable in the vertical direction, and a vertical movement in the slider 12. The punch 13 is slidably mounted in the direction, and is disposed in the slider 12 and elastically biases the slider 12 upward through the punch 13 and the punch 13 so that the punch 13 and the slider 12 are initialized. A return means 15 having a coil spring 14 for returning to a position and a slide guide member 16 provided on the case 11 so as to guide the vertical movement of the punch 13 are provided.

  The slider 12 has a recess 21 and engages with a retaining pin 22 fixed to the case 11 at the recess 21 so that the slider 12 does not slip out of the case 11 due to the elastic force of the coil spring 14. The upper plate holder 2 is pressed downward by the pressing plate 3 when the upper die holder 2 is lowered.

  The punch 13 for punching the thin metal plate 8 has a columnar body, in this example, a columnar body portion 25 and a central portion of one circular end surface 26 of the body portion 25, concentric with the end surface 26, and the end surface 26. Are provided integrally with a circular bottom surface 27 having a diameter d1 smaller than the diameter D1, and a columnar shape having a conical tip, specifically a conical tip 28, in this example a columnar projection 29. The protrusion 31 except at least the tip 28 so as to be slidable on the flange 31 integrally provided on the other circular end surface 30 of the main body 25 and the cylindrical peripheral surface 32 of the protrusion 29. An elastically deformable member 33 is provided that surrounds the peripheral surface 32 and is fixed to the end surface 26 of the main body 25 with an adhesive or the like.

  An elastically deformable member 33 having a rigidity smaller than the rigidity of the main body 25 and the thin sheet metal 8 to be perforated includes a cylindrical peripheral surface 35 flush with the cylindrical peripheral surface 34 of the main body 25, and It has a circular annular surface 36 from which the protrusion 29 protrudes, and a circular annular surface 37 fixed to the end surface 26 of the main body 25, and the peripheral surface 35 and the annular surfaces 36 and 37 of the elastically deformable member 33. The annular surface 36 and the annular surface 37 are parallel to each other and have the same outer diameter.

  The coil spring 14 is in contact with the flange portion 41 at one end and the flange portion 41 of the sliding guide member 16 at the other end. The sliding guide member 16 is integrated with the flange portion 41 in addition to the flange portion 41 and the case 11. The hole 42 has a cylindrical portion 43 fitted to the case 11, and the lower end portion of the body portion 25 of the punch 13 and the elastically deformable member 33 are slidable on the inner peripheral surface of the cylindrical portion 43. Support guide.

  The die 10 has a circular hole 51 into which the punch 13 is inserted, and a circular hole 52 that communicates with the circular hole 51 and has a larger diameter than the circular hole 51 and discharges punch scraps. The ratio D1 / D2 of the diameter D2 of the circular hole 51 to the diameter D1 of the annular surface 36 of the deformable member 33 is 0.80 or more, and when the thickness of the thin metal 8 to be drilled is t, the radius of the annular surface 36 The difference (clearance) f between D1 / 2 and the radius D2 / 2 of the circular hole 51 of the die 10 is 0.15 t or more and 2 mm or less. A circular corner 53 of the die 10 forming the open end of the circular hole 51 is a right angle.

  In the drilling device 1 described above, when the pressing plate 3, the pressing pad 5 and the punch holder 7 are lowered as the upper die holder 2 is lowered, the thin metal plate 8 placed on the lower die 9 is pressed by the pressing pad 5. 5 is sandwiched and fixed between the lower die 9 and the pressing pad 5 and the slider 12 is pressed by the pressing plate 3, and the punch 13 is lowered when the slider 12 is pressed. As described above, the piercing hole 55 is opened in the thin metal plate 8 by the tip 28 of the projection 29, and the movement of the thin plate metal 8 is restricted at the tip 28 inserted into the piercing hole 55 or the portion of the projection 29 following the tip 28. When the punch 13 is further lowered and the elastically deformable member 33 is inserted into the circular hole 51 of the die 10 and the elastically deformable member 33 presses the thin metal plate 8 with the annular surface 36, as shown in FIG. Deformable The member 33 is elastically deformed and rounded at the annular outer peripheral edge (corner portion) 61 of the annular surface 36 in addition to the overall vertical compression, and the outer peripheral edge 61 is rounded and elastically deformed. The sheet metal 8 between the annular surface 36 of the possible member 33 and the tip of the annular corner 62 of the die 10 defining the circular hole 51 is pulled and stretched, and then the corner 62 of the die 10 is stretched. As shown in FIG. 7, the sheet metal 8 is shredded and broken on the side, and after breaking on the corner 62 side of the die 10 of the sheet metal 8, as shown in FIG. While the rounding due to elastic deformation at the outer peripheral edge 61 is eliminated and the punch 13 is raised, the punch scrap 65 is discharged through the circular hole 52, and thus a through-hole 66 is formed in the thin metal plate 8. .

  A punch hole 55 is opened in the thin metal plate 8 by the tip 28 of the protrusion 29, and the punch 13 is inserted into the circular hole 51 of the die 10 with the protrusion 29 inserted in the break hole 55 restricting the movement of the thin metal plate 8. In the punch 13 which breaks the thin metal plate 8 in cooperation with the die 10 around the peripheral surface 35 of the elastically deformable member 33 thus compressed to form the through hole 66 in the thin metal plate 8, In breakage, the outer peripheral edge 61 of the annular surface 36 of the elastically deformable member 33 is elastically deformed and rounded, so that stress concentration of the thin metal plate 8 at the outer peripheral edge 61 can be avoided. As a result of being able to generate concentrated stress on the thin metal plate 8 at the tip of the metal plate 8, it is possible to clearly identify the breaking point of the thin metal plate 8, and in addition to the outer peripheral edge 61 where the elastically deformable member 33 is elastically deformed, the thin metal plate As a result, the main body 25 and the elastically deformable member 33 are inserted into the piercing hole 55 formed by the conical tip 28 of the protrusion 29 while expanding the piercing hole 55. Thus, a desired pulling force can be applied to the thin metal plate 8, and the through hole 66 can be formed at an accurate position without a burr.

  Further, in the punch 13 of this example, in the elimination of rounding due to elastic deformation at the outer peripheral edge 61, as shown in FIG. 7, the protrusion 13 breaks out from the piercing hole 55 by the return elastic force of the compressed elastically deformable member 33. The portion 29 can be forcibly extracted, and the punch scraps 65 can be reliably detached from the elastically deformable member 33, and a situation in which the punch scraps 65 are lifted as the punch 13 is lifted is avoided. be able to.

  In the punching device 1, the punch 13 is moved up and down to form the through hole 66. However, the punch 13 may be moved obliquely to form the through hole 66 in the inclined portion of the thin metal plate 8.

  The above example is preferably used for the punch 13 having a diameter D1 of 1 mm or more, but the present invention is not limited to this, and may be used for the punch 13 having a diameter D1 of less than 1 mm. It is good to use for the punch 13 of 25 mm or less, 10 mm or less, or 5 mm or less. In this case, d1 / D1 may be 0.05 to 0.5.

It is sectional drawing of a preferable example of embodiment of this invention. It is explanatory drawing of a part of punch used for the example shown in FIG. It is a front view of the punch shown in FIG. It is explanatory drawing of the punch and die | dye used for the example shown in FIG. It is operation | movement explanatory drawing of the example shown in FIG. It is operation | movement explanatory drawing of the example shown in FIG. It is operation | movement explanatory drawing of the example shown in FIG. It is operation | movement explanatory drawing of the example shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Drilling device 2 Upper mold holder 3 Pressing plate 4 Elastic member 5 Pressing pad 7 Punch holder 8 Thin metal plate 9 Lower die 10 Die 13 Punch 25 Main body part 26 End surface 27 Bottom surface 28 Tip 29 Projection part 32 Peripheral surface 33 Elastically deformable member

Claims (6)

  A columnar main body, a columnar protrusion having a conical tip provided integrally with the central portion of one end surface of the main body, and at least a protrusion excluding the conical tip And an elastically deformable member provided on one end surface of the main body, and the elastically deformable member has a rigidity smaller than the rigidity of the main body and the thin plate metal to be perforated. A punch for punching a sheet metal having a cylindrical peripheral surface flush with the cylindrical peripheral surface of the main body.   2. The punch for punching a thin metal plate according to claim 1, wherein the elastically deformable member has an annular surface that is orthogonal to the cylindrical peripheral surface and from which the protruding portion protrudes.   The elastic metal deformable member is fixed to one end face of the main body and surrounds the protrusion so as to be slidable on the protrusion. punch.   An elastically deformable member that has been compressed by inserting a punch into the die hole with the protrusion inserted into the piercing hole, and a punch being inserted into the die hole with the protrusion inserted into the piercing hole. The thin plate metal hole according to any one of claims 1 to 3, which is used in a thin plate metal drilling device configured to break a thin plate metal around a peripheral surface of the metal plate to form a through hole in the thin plate metal. A punch for the dawn.   A sheet metal drilling device comprising the punch for punching a sheet metal according to any one of claims 1 to 4, and a die having a hole into which the punch is inserted.   6. A method of forming a through-hole in a thin metal plate by the thin metal punching device according to claim 5, wherein a through-hole is formed in the thin metal plate by a tip of the protrusion, and the thin metal is formed by the protrusion inserted in the through-hole. By inserting a punch into the hole of the die while restricting the movement of the die, the sheet metal is broken around the peripheral surface of the compressed elastically deformable member to form a through hole in the sheet metal. how to.

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