JP5678933B2 - Sheet metal drilling device having punch for punching sheet metal - Google Patents

Description

  The present invention relates to a punch for punching a sheet metal, a punching apparatus for a sheet metal provided with the punch, and a method thereof.

  A punch having a cylindrical punch body having an outer diameter smaller than the hole diameter of the die and a conical protrusion integrally formed on one end face of the punch body is pressed against a thin metal plate, and the thin plate is formed by the protrusion of the punch. A punch is made by drilling a piercing hole in advance of the metal, and further inserting the punch body into the die hole from one end of the die hole in a state where the movement of the sheet metal is restricted by the protrusion inserted into the piercing hole. A drilling device has been proposed in which a sheet metal is broken around an annular edge of a cylindrical inner surface of a die that defines one end of a die hole in cooperation with the main body to form a through hole in the sheet metal. (For example, see Patent Documents 1 and 2).

JP 2005-262263 A JP 2002-153920 A

  According to such a drilling device, the thin plate metal is positioned by the protrusion, and moreover, a tensile force rather than a shearing force is applied to the thin metal plate to form a through hole, so that the through hole can be accurately penetrated without causing a burr. Although the hole can be formed in the sheet metal, when the hole diameter of the through-hole formed in the sheet metal is reduced, the annular shape of the punch body that applies a tensile force to the sheet metal in cooperation with the annular edge of the cylindrical inner surface of the die. The end surface is substantially absent from the curved portion of the outer peripheral edge of the end surface and the bottom surface of the projection, and the piercing hole itself is expanded by the punch body following the formation of the piercing hole in the sheet metal by the projection of the punch, There is a possibility that the through hole cannot be formed in the thin metal plate by the pulling force.

  Therefore, in order to secure an end surface of a certain size (wideness) in the punch body, if the cone angle at the tip of the conical protrusion is reduced to reduce the width of the bottom surface of the protrusion, the protrusion becomes extremely thin. While it becomes difficult to ensure the strength of the protrusion and the durability deteriorates, if the overall height of the protrusion is lowered and the width of the bottom surface of the protrusion is reduced, the breakthrough hole by the protrusion After the formation of the punch, the protrusions come out of the piercing holes and the movement of the sheet metal can no longer be controlled, and the pulling force is uniformly applied to the sheet metal by the end face of the punch body in cooperation with the annular edge of the cylindrical inner surface of the die. There is a risk that it will not be possible.

  The present invention has been made in view of the above-mentioned points, and the object of the present invention is to ensure the strength of the projections despite the fact that the punch body can secure an end surface of a certain size (width). It does not lead to deterioration of durability, and even after the formation of the piercing hole, it is possible to secure the regulation of the movement of the thin metal plate with the protrusion, and to position the thin metal plate, and to avoid the diameter expansion of the piercing hole itself by the punch body, Thus, the thin plate metal can be formed by forming a through hole in the thin plate metal by pulling the thin plate metal around the annular edge of the cylindrical inner surface of the die that defines one end of the die hole in cooperation with the punch body. An object of the present invention is to provide a punch for punching, an apparatus for punching a thin metal plate provided with the punch, and a method thereof.

  A punch for punching a thin metal plate according to the present invention includes a columnar punch body and a protrusion integrally provided on one end surface of the body, where the protrusion is one of the punch bodies. A columnar portion integrally provided with a bottom surface and a top surface on the end surface of the plate, and a conical portion integrally provided on the top surface of the columnar portion. The punch body is parallel to the axis. An extended cylindrical surface, an annular surface surrounding the bottom surface of the columnar portion and extending perpendicular to the axis, and a curved surface extending from the outer edge of the annular surface to one edge of the cylindrical surface are provided.

  According to such a punch for punching a thin metal plate, since the projection has a columnar portion integrally provided with a bottom surface and a top surface on one end surface of the punch main body, Even if the height of the protrusion is made high so that the apex angle is increased so that sufficient strength and durability can be obtained and the protrusion is prevented from coming out of the piercing hole after the piercing hole is formed by the protrusion, the columnar portion of the protrusion An annular surface that surrounds the bottom surface of the punch body and that extends perpendicular to the axis can be secured to the end surface of the punch body with a sufficient width, and thus the punch body itself can be prevented from expanding its diameter. The through hole is accurately formed in the sheet metal without causing burrs by pulling the sheet metal securely around the annular edge of the cylindrical inner surface of the die that defines one end of the die hole in cooperation with the punch body. Can be formed

  The punch for punching a thin metal plate according to the present invention has a punch hole formed in the thin metal plate by a protrusion, and the punch is further formed into a die hole in a state where the movement of the thin metal plate is restricted by the columnar portion of the protrusion inserted into the break hole. By inserting from one end of the die hole, the sheet metal is broken around the annular edge of the cylindrical inner surface of the die that defines one end of the die hole, thereby forming a through hole in the sheet metal. It is good to use for the punching device of a thin metal plate.

  In the present invention, the punch body is a columnar shape including a triangular prism, a quadrangular column, and a polygonal column, and the conical portion only needs to be a conical shape including a triangular pyramid, a quadrangular pyramid, and a polygonal pyramid. In this case, the punch for punching the thin metal plate according to the present invention is provided integrally with the cylindrical punch body and one circular end face of the punch body. Here, the protrusion is formed on the circular end surface of the punch main body, and the cylindrical portion integrally provided with the circular bottom surface and the circular top surface concentrically with the circular end surface. And a conical portion integrally provided on the circular top surface of the columnar portion, and the punch body surrounds the cylindrical surface extending parallel to the axis and the circular bottom surface of the columnar portion. And an annular surface extending perpendicular to the axis and the outer edge of the annular surface And a curved surface extending to one edge of the cylindrical surface may be equipped.

  In a punch for punching having a cylindrical punch body, the radius of the punch body should be r1, the radius of curvature of the curved surface should be r2, the radius of the cylindrical part should be r3, the height of the cylindrical part should be h, and the hole should be punched When the thickness of the thin metal plate is t, r3 <r1-r2 and h> t + r3 may be satisfied.

  In a preferred example, the diameter of the cylindrical punch body is in the range of 1 mm to 25 mm, 1 mm to 10 mm, or 1 mm to 5 mm, but the present invention is not limited thereto.

  The punch for punching a thin metal plate having a cylindrical punch body is further formed in a state where a hole is drilled in the thin metal plate by the protrusion, and the movement of the thin metal plate is restricted by the cylindrical portion of the protrusion inserted into the through hole. By inserting the punch into the hole of the die from one end of the hole, the sheet metal is broken around the annular edge of the cylindrical inner surface of the die that defines one end of the hole to form a through hole in the sheet metal. It is good to use for the punching apparatus of the sheet metal which has become.

  In the present invention, the cylindrical portion of the protrusion may be a cylindrical portion having the same diameter in the circular bottom surface and the circular top surface. Instead, the diameter of the circular top surface is smaller than that of the circular bottom surface. It may be a so-called frustoconical columnar portion in which the angle of the apex when the head cone surface is extended is smaller than the angle of the apex of the conical portion of the projection, and the curved surface causes burrs. In order to reduce the shearing effect and to better pull and break the sheet metal, it is preferable to have a curvature radius R of 0.1 mm to 5 mm.

  A sheet metal drilling apparatus includes the punch for punching a sheet metal according to any one of the above aspects and a die having a hole or a circular hole into which the punch is inserted.

  The difference as the clearance of the punch body with respect to the die hole or the circular hole is 0.15 t or more and 2 mm or less, where t is the thickness of the sheet metal.

  The method according to the present invention for forming a through-hole in a thin metal plate by the above-described thin metal hole drilling device is a method in which a through-hole is formed in a thin metal plate by a protrusion, and the thin plate metal is formed by a columnar portion or a cylindrical portion of the protrusion inserted into the through-hole. The cylindrical inner surface of the die or the annular inner surface of the die that defines one end of the hole or circular hole by inserting the punch into the hole or circular hole of the die from one end of the hole or circular hole with the movement of It consists of breaking a sheet metal around an edge or an annular edge.

  The sheet metal drilled by the drilling apparatus or method of the present invention has a thickness of about 0.4 mm to 2.0 mm in order to obtain good results. Has a thickness of about 0.6 mm to 1.6 mm.

  According to the present invention, although the end face of a certain size (wide) can be secured on the punch body, the strength of the projection can be secured without causing deterioration in durability, and after the piercing hole is formed. In addition, it is possible to secure the regulation of the movement of the sheet metal with the projections, and to position the sheet metal and to avoid the diameter expansion of the piercing hole itself by the punch body, thus defining one end of the die hole in cooperation with the punch body A punch for punching a thin metal plate which can be surely broken by pulling the thin metal plate around the annular edge of the cylindrical inner surface of the die to form a through hole in the thin metal plate, and a thin plate metal punching device equipped with this punch As well as a method thereof.

FIG. 1 is a cross-sectional view of a preferred example of an embodiment of the present invention. FIG. 2 is an explanatory view of a part of the punch used in the example shown in FIG. FIG. 3 is a front view of the punch shown in FIG. FIG. 4 is an explanatory diagram of the punch and the die used in the example shown in FIG. FIG. 5 is an operation explanatory diagram of the example shown in FIG. FIG. 6 is an operation explanatory diagram of the example shown in FIG. FIG. 7 is an operation explanatory diagram of the example shown in FIG. FIG. 8 is a diagram for explaining the operation of the example shown in FIG. FIG. 9 is a diagram for explaining the operation in the conventional example.

  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. Punch 13 mounted slidably in the direction, and disposed in slider 12 and elastically urges slider 12 upward via punch 13 to return punch 13 and slider 12 to their initial positions. Returning means having a coil spring 14 to be moved, and a sliding guide member 15 provided in 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 8 includes a cylindrical punch body 25, a protrusion 27 integrally provided on a circular end surface 26 which is one end surface of the punch body 25, and the other end surface of the punch body 25. And a flange 29 provided integrally with the circular end face 28.

  The punch body 25 includes a cylindrical surface 32 extending parallel to the axis 31, an annular surface 33 extending perpendicular to the axis 31, and a curved surface 34 extending from the outer edge of the annular surface 33 to the outer edge of the cylindrical surface 32. The diameter D1 (= 2 × r1) of the punch body 25 is in the range of 1 mm to 25 mm, 1 mm to 10 mm, or 1 mm to 5 mm, and the radius of curvature r2 of the curved surface 34 is from 0.1 mm. The range is 5 mm.

  The protrusion 27 is arranged on one circular end surface 26 of the punch body 25 concentrically with the circular end surface 26 and has a circular bottom surface 41 having a diameter D3 (= 2 × r3) smaller than the diameter D1 of the circular end surface 26. Further, the columnar portion 43 having a height h integrally provided on the circular bottom surface 41 with the circular top surface 42 and the circular top surface 42 of the columnar portion 43 are arranged concentrically with the circular top surface 42. A circular bottom surface 44 having the same diameter as the diameter D3 of the circular top surface 42 and a conical portion 45 provided integrally with the circular bottom surface 44, and the circular bottom surface 41 of the columnar portion 43, The punch body 25 is surrounded by an annular surface 33.

  In the punch 13 described above, the radius of the punch body 25 is r1 (= D1 × 1/2), the radius of curvature of the curved surface 34 is r2, the radius of the cylindrical portion 43 is r3 (= D3 × 1/2), and the columnar shape. When the height of the portion 43 is h and the thickness of the thin metal 8 to be punched is t, r3 <r1-r2 and h> t + r3.

  The coil spring 14 is in contact with the flange 29 at one end and the flange portion 51 of the sliding guide member 15 at the other end. The sliding guide member 15 is integrated with the flange portion 51 in addition to the flange portion 51 and the case 11. The hole 52 has a cylindrical portion 53 fitted in the case 11, and the lower end portion of the punch body 25 of the punch 13 is slidably guided and supported on the inner peripheral surface of the cylindrical portion 53.

  The die 10 has a circular hole 61 into which the punch 13 is inserted, and a circular hole 63 which is continuous with the circular hole 61 and has a larger diameter than the circular hole 61 and discharges punch scraps 62 (see FIG. 8). And the ratio D1 / D4 of the diameter D4 of the circular hole 61 to the diameter D1 of the circular end face 26 is 0.80 or more, and when the thickness of the thin metal 8 to be drilled is t, the radius of the circular end face 26 The difference (clearance) f between r1 (= D1 × 1/2) and the radius r4 (= D4 × 1/2) of the circular hole 61 of the die 10 is 0.15 t or more and 2 mm or less. The circular hole 61 is defined by the cylindrical inner surface 64 of the die 10, and one annular edge 65 of the cylindrical inner surface 64 is one annular shape of the die 10 orthogonal to the cylindrical inner surface 64 and the cylindrical inner surface 64. This is a right-angled edge defined by the crossing edge with the end face 66 of the first electrode.

  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. Thus, the piercing hole 71 is opened in the thin metal plate 8 by the conical portion 45 of the protrusion 27 and subsequently by the cylindrical portion 43, and the thin plate metal 8 is moved by the cylindrical portion 43 of the protrusion 27 inserted into the piercing hole 71. When the punch 13 is further lowered and the punch body 25 of the punch 13 is inserted into the circular hole 61 of the die 10 as shown in FIG. Metal 8 is this When the punch body 25 is pushed down by the annular surface 33 and lowered, the curved surface 34 of the circular end surface 26 and the annular edge 65 of the cylindrical inner surface 64 of the die 10 defining one end of the circular hole 61 are formed. Then, the sheet metal 8 between them is pulled and stretched, and then the sheet metal 8 is torn and broken on the annular edge 65 side of the die 10 as shown in FIG. After the fracture at the annular edge 65 side, the punch 13 is raised as shown in FIG. 8, while the punch scraps 62 are discharged through the circular hole 63, and thus the through-hole 72 is formed in the thin metal plate 8. The

  By the way, in the punch 13, since the protrusion 27 has the cylindrical portion 43 integrally provided with the circular bottom surface 41 and the circular top surface 42 on one annular surface 33 of the punch body 25, The conical angle of the tip of the conical portion 45 is increased so as to obtain sufficient strength and durability, and the protrusion 27 is removed from the piercing hole 71 after the piercing hole 71 is formed by the protrusion 27 (FIG. 9 shows a conventional example). Even if the entire protrusion 27 is raised so as to prevent the protrusion 27 from coming out of the breakthrough hole 71, the circular bottom surface 41 of the cylindrical portion 43 of the protrusion 27 is surrounded and orthogonal to the axis 31. The annular surface 33 extended in this manner can be secured to the circular end surface 26 of the punch body 25 with a sufficient width, and thus, the die 10 that defines one end of the circular hole 61 of the die 10 in cooperation with the punch body 25. Is reliably broken sheet metal 8 around the annular rim 65 of the cylindrical inner surface 64 of the through hole 72 in the sheet metal 8 can be precisely formed.

  Moreover, since the curved surface 34 has a radius of curvature r2 of 0.1 mm to 5 mm, it is possible to reduce the effect of shearing that causes burrs and to pull and break the sheet metal 8 more favorably. In addition, the ratio D1 Since / D4 is 0.80 or more and the difference f is 0.15 t or more, in addition to some shear, mainly tensile fracture is caused to effectively form the through hole 72 in the thin metal plate 8. be able to.

  In the punching device 1, the punch 13 is moved up and down to form the through hole 72. However, the punch 13 may be moved obliquely to form the through hole 72 in the inclined portion of the thin metal plate 8.

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 Punch main body 26 Circular end surface 27 Projection 28 Circular end surface 29 鍔

Claims (2)

It comprises a punch for punching a thin metal plate and a die having a circular hole into which the punch is inserted. The punch is integrated with a cylindrical punch body and one circular end face of the punch body. The protrusion is provided on the cylindrical body, and the protrusion is integrally formed with one circular end surface of the punch body with a circular bottom surface and a circular top surface that are concentric with the circular end surface. And a conical portion integrally provided on the circular top surface of the columnar portion, and the punch body surrounds the cylindrical surface extending parallel to the axis and the circular bottom surface of the columnar portion. And an annular surface extending perpendicular to the axial center and a curved surface extending from the annular outer edge of the annular surface to the annular edge of the cylindrical surface. A thin plate metal with a cylindrical part of a protrusion that is drilled and inserted into the piercing hole In a state where the movement is restricted, the punch is inserted into the circular hole defined by the cylindrical inner surface of the die from one end of the circular hole, thereby defining one end of the circular hole and the cylindrical shape of the die with which the sheet metal contacts. In the insertion direction of the punch body , the right annular ring edge, which is the crossing edge of one annular end surface of the inner surface and the die, and the curved surface of the punch body that contacts the sheet metal whose movement is defined by the cylindrical portion of the protrusion a between the curved surface of the right-angled annular edge and a punch body, and, between the cylindrical inner surface and the cylindrical surface of the punch body in a die in the radial direction of the punch body, it is moved in the cylindrical portion of the projection The specified sheet metal is shredded and the sheet metal is broken around the right circular ring edge to form a through hole in the sheet metal, and the cylindrical surface of the punch body and the cylindrical inner surface of the die Cylindrical gap between The radial width is from 0.15 t to 2 mm, where t is the thickness of the sheet metal, the radius of the punch body is r1, the radius of curvature of the curved surface is r2, the radius of the cylindrical portion is r3, and the circle When the height of the columnar part is h, r3 <r1−r2 and h> t + r3, and the columnar part prevents the protrusion from coming out from the piercing hole after the piercing hole is formed by the protrusion. Sheet metal drilling device.   2. The sheet metal drilling device according to claim 1, wherein the punch body has a diameter in the range of 1 mm to 25 mm, 1 mm to 10 mm, or 1 mm to 5 mm.

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