JP7224669B2 - Methods of producing cases and final workpieces - Google Patents

Description

The present invention is a cylinder in which a thin portion with a relatively thin wall thickness from the outer surface to the inner surface and a thick portion with a relatively large wall thickness from the outer surface to the inner surface are set side by side along the circumferential direction. and the final workpiece from which the case is formed.

Conventionally, a thin portion with a relatively thin thickness from the outer surface to the inner surface and a thick portion with a relatively thick thickness from the outer surface to the inner surface are arranged side by side in the circumferential direction to form a cylinder. Articles have sometimes been produced by forming a workpiece by backward extrusion (see, for example, US Pat.

Japanese Utility Model Publication No. 41-016203

However, in the conventional technology described in Patent Document 1, in the produced article, the surface of the end formed by extending the material constituting the work by backward extrusion molding is not flat, and this surface is flattened. In order to do so, there was a problem that cutting was required as appropriate.

The present invention makes it possible to produce a case with a flatter end face when it is produced by rearward extrusion.

According to one feature of the present invention, a portion forming a cylinder having an inner surface and an outer surface, and a portion serving as a bottom covering one end of the cylinder are provided, and a thin portion is provided along the circumferential direction of the cylinder. A method for producing a case is provided that produces a case having a thick portion and a thick portion set side-by-side. Here, the thin portion is a portion that is relatively thin from the outer surface to the inner surface, and the thick portion is a portion that is thicker from the outer surface to the inner surface than the thin portion. In this method of manufacturing the case, the final workpiece that will be the material to be molded into the case is divided into a first portion that will be the thick portion when molded into the case and a second portion that will be the thin portion when molded into the case. 2. A portion is prepared in a state having a portion of 2. Here, the height of the first portion seen in the axial direction along which the cylinder extends when the final work is formed into the case is lower than the height of the second portion seen in the axial direction. Further, in the method for producing the case, the final workpiece is inserted into the hole in the die having a hole formed in a shape corresponding to the outer surface and extending in a predetermined direction, and the axial direction of the final workpiece is in the above-mentioned one direction. Set the posture to match the direction. Further, in the method of manufacturing the case, the final work is pressed from the one direction by the first punch provided with a pressing portion having a projection having a shape corresponding to the inner surface, and the final work is formed by backward extrusion molding. case.

The present inventor has arrived at the present invention by focusing on the fact that the narrower the width of the gap through which the material flows, the smaller the amount of elongation of the material that constitutes the final workpiece in backward extrusion molding. . That is, when forming the above case by backward extrusion, the gap between the wall of the die hole and the first punch is relatively wide in the first portion of the final workpiece and wide in the second portion. is set relatively narrow, the thicker portion will stretch more than the thinner portion during backward extrusion. On the other hand, in the case production method described above, the height of the first portion, which is the thick portion, is made lower than the height of the second portion, which is the thin portion, to reduce the influence of the difference in elongation. This can be offset so that the edge surface formed by this elongation can be made flatter.

In the above-described method for producing a case, a punch member provided with a pressing portion and a stepped portion protruding radially outward from the projection formed by the pressing portion at the root portion of the projection formed by the punching member is provided. , is preferably used as the first punch. In this case, when the final work is pressed from the one direction by the first punch, the axial end of the final work formed by this pressing is brought into contact with the stepped portion to shape the end.

According to the method for producing the case described above, the end surface formed by the elongation of the case to be produced is shaped by the stepped portion of the first punch, thereby making the end surface flatter. can do.

In the method for producing the case described above, it is preferable to prepare the final workpiece in the following conditions. That is, the final work consists of a disk-shaped body portion and a base portion formed as a solid base at the end which will be the bottom side of the hole when the final work is set in the die hole. and have Also, in the final work, the two second portions are provided on the side portions of the disk formed by the main body so as to sandwich the disk from its radial direction. Also, in the final work, the two first portions are provided in the portion sandwiched between the two second portions on the side portion of the disk formed by the body portion. Also, in the final work, one smooth curved surface is formed on the edge of the end face opposite to the pedestal in the two first portions and on the opposite side to the pedestal in the two second portions. It is set across the edge of the end face that becomes

According to the method for producing the case described above, it is possible to make the surface of the end of the produced case formed by the elongation of the rearward extrusion a smooth surface, thereby facilitating the flattening of the surface of the end.

In the above case, the end surface of the two first portions opposite to the pedestal portion and the end surface of the two second portions opposite to the pedestal portion are separated from each other. It is preferable to prepare in a state in which the curved surface is formed as a whole.

According to the method for producing the case described above, it is possible to make the surface of the end of the produced case formed by the elongation of the rearward extrusion a smooth surface, thereby facilitating the flattening of the surface of the end.

In the method for producing the case described above, the final workpiece can be loosely fitted to the pressing portion of the first punch on the portion opposite to the pedestal portion of the main body portion. Preferably, it is provided with a reserve hole, which is a hole of size and shape. In this case, when pressing the final work from the one direction with the first punch, the pressing portion of the first punch is inserted into the preliminary hole.

According to the method for producing the case described above, when the case is produced by backward extrusion molding, the backlash of the final workpiece is suppressed by fitting the preliminary hole with the pressing portion of the first punch. The shape accuracy of the case can be improved. Further, since the fit is a clearance fit, the pressing portion of the first punch can be smoothly inserted into the preliminary hole.

In the method of producing the above case, a perforated member having a cylindrical hole is used as a die, and the projection formed by the pressing part has a long diameter smaller than the inner diameter of the cylindrical shape. Preferably, a shaped punch member is used as the first punch. In this case, the final work has a body portion forming a disk, and two second portions are provided on the sides of the disk formed by the body portion so as to sandwich the disk from its radial direction. Prepare it in a ready state. Further, when the final work is pressed from the one direction by the first punch, the longitudinal direction of the two-sided shape of the first punch should be aligned with the direction in which the two second portions sandwich the main body. do.

Here, the term "two-sided shape" refers to a shape obtained by cutting both ends of a cylinder as a base as seen in the radial direction, and making the two ends parallel to each other. In the two-sided shape, the "longitudinal direction" refers to a direction parallel to the planes of both ends and perpendicular to the axial direction of the base cylinder. In addition, in the two-sided shape, the "major axis" means the length in the longitudinal direction. Here, in the two-sided projection, since the two side surfaces forming the ends in the longitudinal direction are positioned on one virtual cylindrical surface, it is easy to center with respect to the cylindrical hole or shaft. There is a feature that it can be done in That is, according to the above-described method for producing a case, it is possible to form a case having a thin portion and a thick portion while forming the projection of the pressing portion in a relatively simple shape of a two-sided shape. centering of the punch can be facilitated.

In the method of producing the above case, a perforated member having a cylindrical hole is used as a die, and the projection formed by the pressing part has an oval bottom surface with a longer diameter smaller than the inner diameter of the cylindrical shape. It is preferable to use a punch member having a straight columnar shape as the first punch. In this case, the final work has a body portion forming a disk, and two second portions are provided on the sides of the disk formed by the body portion so as to sandwich the disk from its radial direction. Prepare it in a ready state. Further, when the final work is pressed from the one direction by the first punch, the longitudinal direction of the oval shape of the first punch is made to match the direction in which the two second portions sandwich the main body. .

Here, the term "oval" refers to a shape surrounded by two parallel line segments of the same length and two semicircles having a diameter equal to the distance between these parallel line segments. In addition, in the oval, the "longitudinal direction" refers to the direction in which the parallel line segments extend. Moreover, in an elliptical shape, the "major axis" means the maximum length in the longitudinal direction. That is, according to the method for producing the case described above, a case having a thin portion and a thick portion is molded while the protrusion of the pressing portion is formed in a relatively simple shape of a straight column having an oval bottom surface. can be realized.

In the method for producing the case described above, the intermediate work, which is the material to be molded into the final work, is pressed by the second punch provided with pressing surfaces having shapes corresponding to the first portion and the second portion. Therefore, it is preferable to mold the intermediate work by backward extrusion molding to form the final work.

When an object is backwardly extruded by the pressing surface, a shape corresponding to the pressing surface is transferred to the object. That is, according to the method for producing the case described above, the first portion and the second portion of the final work are formed by transferring the shape corresponding to the pressing surface of the second punch, thereby preparing the final work. It can make your work easier.

In the method of producing the case described above, it is preferable to produce a billet, which is a material to be molded into the intermediate work, by cutting a wire rod. In this case, an intermediate work is produced by rounding the edge of the cut end of the billet by pressing. Then, the cut end of the intermediate work is pressed by the second punch to form the intermediate work into the final work.

According to the method of producing the case described above, the edges at the cut ends of the intermediate workpieces are rounded prior to pressing by the second punch, thereby reducing the risk of the edges being crushed by the pressing and forming burrs.

In the method for producing the case described above, it is preferable to prepare a metal wire made of aluminum or an aluminum alloy as the wire. In this case, each of the following steps is performed by cold forging. Here, each of the above steps includes a step of producing an intermediate work in which the edge of the cut end of the billet is rounded by surface pressing. Each of the above steps includes a step of pressing the cut end of the intermediate work with a second punch to form the intermediate work into the final work. Further, each of the above steps includes a step of pressing the final work with the first punch and forming the final work into a case.

According to the method for producing the case described above, the case is produced as a product formed by cold forging aluminum or an aluminum alloy. As a result, the produced case can have the merits of the cold forged product (for example, less dimensional variation due to heat influence, etc.).

In the method of producing the case described above, it is preferred that each of the following steps be included in a series of steps performed by a single parts former. Here, the series of steps includes a step of producing a billet by cutting the wire rod. Moreover, the series of steps includes a step of producing an intermediate work in which the cut edge of the billet is rounded by surface pressing. The series of steps also includes a step of pressing the cut end of the intermediate work with a second punch to form the intermediate work into the final work. Further, the series of steps includes a step of pressing the final work with the first punch and forming the final work into a case.

Here, the term "part former" refers to a processing device that cuts a set wire rod into a billet and presses the billet a plurality of times as a series of steps. That is, according to the method for producing the case described above, the case can be produced by a simple operation of setting the wire rod in the parts former and operating the parts former.

Also provided is the invention of the final workpiece that is the material to be molded into the case. Here, the case includes a portion forming a cylinder having an inner side surface and an outer side surface, and a bottom portion closing one end of the cylinder. are set side by side. Also, the thin portion is a portion having a relatively thin thickness from the outer surface to the inner surface, and the thick portion is a portion having a greater thickness from the outer surface to the inner surface than the thin portion. This final workpiece has a body portion that forms a disc. Moreover, the final work includes two second portions provided on the sides of the disk formed by the main body so as to sandwich the disk from its radial direction. Also, the final work includes two first portions provided at portions sandwiched between the two second portions on the sides of the disk formed by the body portion. Also, the final workpiece has a platform portion formed as a solid platform on one side of the disk of the body portion. Here, the height of the first portion of the disk of the main body viewed in the axial direction is lower than the height of the second portion viewed in the axial direction.

According to the above-mentioned final work, the height of the first portion, which is the thick portion, is made lower than the height of the second portion, which is the thin portion, to offset the influence of the difference in the amount of elongation between them. The end face of the molded case can be made flatter.

In the above final workpiece, one smooth curved surface is formed on the edge of the end face opposite the pedestal in the two first parts and on the opposite side of the pedestal in the two second parts. It is preferable that it is set across the edge of the end face that becomes .

According to the above-described final workpiece, the end surface formed by the elongation by the backward extrusion molding in the produced case can be made into a smooth surface, thereby facilitating flattening of the end surface.

In the above-mentioned final work, the end surfaces of the two first portions opposite to the pedestal portions and the end surfaces of the two second portions opposite to the pedestal portions as a whole are A curved surface is preferred.

According to the above-described final workpiece, the end surface formed by the elongation by the backward extrusion molding in the produced case can be made into a smooth surface, thereby facilitating flattening of the end surface.

It is preferable that the final work can be formed into the case by rearward extrusion molding by pressing the final work with a pressing portion having a projection having a shape corresponding to the inner surface. This final work further includes a preliminary hole, which is a hole having a size and shape that allows a loose fit with the pressing portion, on the opposite side of the main body portion to the pedestal portion. have.

According to the above-mentioned final work, when the case is produced by backward extrusion molding, rattling of the final work can be suppressed by fitting the preliminary hole and the pressing portion, thereby improving the shape accuracy of the produced case. can be done. Further, since the fit is a clearance fit, the pressing portion can be smoothly inserted into the preliminary hole.

According to the method and the final workpiece for producing the case of the present invention, the edge surface can be made flatter when producing the case by backward extrusion.

It is a front view showing case 10 concerning a 1st embodiment of the present invention. FIG. 2 is a rear view showing the case 10 of FIG. 1; FIG. 2 is a right side view showing the case 10 of FIG. 1; FIG. 2 is a bottom view showing the case 10 of FIG. 1; FIG. 2 is a perspective view showing a case 10 of FIG. 1; FIG. 2 is an explanatory diagram for explaining a method of producing the case 10 of FIG. 1; FIG. 2 is an explanatory diagram for explaining a method of producing the case 10 of FIG. 1; FIG. 2 is an explanatory diagram for explaining a method of producing the case 10 of FIG. 1; FIG. 2 is an explanatory diagram for explaining a method of producing the case 10 of FIG. 1; FIG. 2 is an explanatory diagram for explaining a method of producing the case 10 of FIG. 1; 11 is a front view showing the final work 11 of FIG. 10; FIG. FIG. 11 is a rear view showing the final work 11 of FIG. 10; 11 is a right side view showing the final work 11 of FIG. 10; FIG. 14 is an enlarged view of the XIV part of FIG. 13; FIG. 11 is a bottom view showing the final work 11 of FIG. 10; FIG. FIG. 11 is a perspective view showing the final work 11 of FIG. 10; 13 is a cross-sectional view taken along line XVII-XVII of FIG. 12; FIG. FIG. 2 is an explanatory diagram for explaining a method of producing the case 10 of FIG. 1; FIG. 19 is a perspective view showing the punch 21 of FIG. 18; FIG. 19 is a front view showing the punch 21 of FIG. 18; It is an explanatory view for explaining a method of producing a case according to a second embodiment of the present invention. FIG. 22 is an explanatory diagram for explaining a method of preparing the final work 31 of FIG. 21; FIG. 22 is a front view showing the final work 31 of FIG. 21; 22 is a rear view showing the final work 31 of FIG. 21; FIG. 22 is a right side view showing the final work 31 of FIG. 21; FIG. 26 is an enlarged view of the XXVI portion of FIG. 25; FIG. FIG. 22 is a bottom view showing the final work 11 of FIG. 21; FIG. 25 is a cross-sectional view taken along line XXVIII-XXVIII of FIG. 24;

EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated using drawing.

<First Embodiment>
First, the case 10 produced by the method for producing a case according to the first embodiment will be described. This case 10 is a case that is used while containing predetermined contents (not shown).

The case 10 is a cold forged product of aluminum or an aluminum alloy, and as shown in FIGS. . As a result, the case 10 has a thin portion 10A that is relatively thin from the outer surface 10D to the inner surface 10C, and a thick portion from the outer surface 10D to the inner surface 10C that is thicker than the thin portion 10A. The shape of the portion 10B is set (that is, the shape of uneven thickness). Here, in the case 10, the thin portion 10A and the thick portion 10B are set in a state in which two each are arranged along the circumferential direction of the cylinder of the case 10 (see FIG. 5). The case 10 also has a bottom portion that closes one end (the left end in FIG. 3) of the cylindrical portion.

In case 10, the top surface appears symmetrical with the bottom surface (see FIG. 4). Also, in the case 10, the left side appears symmetrically with the right side (see FIG. 3).

As shown in FIG. 18, the case 10 is obtained by molding a final workpiece 11, which is a material for molding the case 10, by one backward extrusion molding. As shown in FIGS. 11 to 17, the final workpiece 11 includes a disk-shaped body portion 11A (see FIG. 12) and a solid body portion 11A on one side (lower side in FIG. 15) of the disk of the body portion 11A. (See FIG. 17) is integrated with a platform portion 11D formed as a platform. The pedestal portion 11D has a bottom surface covering the entire surface of one side of the disk of the main body portion 11A and forms a right cone frustum whose axis coincides with the axis (not shown) of the disk of the main body portion 11A. It can also be said that the pedestal portion 11D is formed by chamfering the edge of one side (lower side in FIG. 15) of the disk-shaped main body portion 11A.

Here, in the rear extrusion molding, the final work 11 extends in the axial direction (the vertical direction in FIG. 18) of the disk of the main body portion 11A, thereby forming the case 10 forming a cylinder extending in this direction. The final workpiece 11 has a first portion 11B that will become the thick portion 10B when molded into the case 10, and a second portion 11C that will become the thin portion 10A when molded into the case 10. have one by one.

The two second portions 11C are provided on the sides of the disk formed by the body portion 11A so as to sandwich the disk from the radial direction thereof. In other words, the two second portions 11C are provided at positions corresponding to both ends of the disk formed by the main body portion 11A when viewed in one of the radial directions (vertical direction in FIG. 12). Also, the two first portions 11B are provided on the side portion of the disk formed by the main body portion 11A at the portion sandwiched between the two second portions 11C. In the following description, the direction in which the disc of the main body 11A is sandwiched between the two second portions 11C is defined as the vertical direction of the final work 11, and the axial direction of the disc of the main body 11A is defined as the front-rear direction of the final work 11. .

Here, as shown in FIG. 13, the two second portions 11C have the same height 11F when viewed in the axial direction of the disk of the body portion 11A with reference to the bottom surface of the pedestal portion 11D. is set to Moreover, as shown in FIG. 15, the two first portions 11B have the same height 11E when viewed in the axial direction of the disk of the main body portion 11A with respect to the bottom surface of the pedestal portion 11D. is set. The height 11E of the first portion 11B is set lower than the height 11F of the second portion 11C, as shown in FIG.

In addition, in the final workpiece 11, the top surface appears symmetrical with the bottom surface (see FIG. 15). Also, in the case 10, the left side appears symmetrical with the right side (see FIG. 13). That is, the two second portions 11C and the two first portions 11B have a plane of symmetry 11H ( 12), they are arranged so as to be plane-symmetrical. From this, it can be said that the two first portions 11B are arranged side by side in the left-right direction of the final work 11 .

Also, in the two first portions 11B and the two second portions 11C, end surfaces 11G and 11J opposite to the pedestal portion 11D (upper side in FIG. 17) are smooth surfaces. These end surfaces 11G and 11J are connected to each other to form one smooth curved surface 11K. In other words, the end surface 11G of the two first portions 11B opposite the pedestal portion 11D and the end surface 11J of the two second portions 11C opposite the pedestal portion 11D It constitutes two smooth curved surfaces 11K. The curved surface 11K consists of an edge portion of an end surface 11G opposite to the pedestal portion 11D in the two first portions 11B and an end surface 11J opposite to the pedestal portion 11D in the two second portions 11C. It can be said that it is set across the edge of the

Here, as shown in FIG. 17, the curved surface 11K is formed so that the line of intersection obtained by cutting the curved surface 11K in the lateral direction of the final workpiece 11 (horizontal direction in FIG. 17) is a straight line. From this, it can be said that the curved surface 11K is a flat curved surface (that is, a curved surface whose Gaussian curvature is 0). In this embodiment, the curved surface 11K has the shape of an R surface with a predetermined radius of curvature. Further, as shown in FIG. 14, the edge 11L, which is the edge of the curved surface 11K, has a chamfered shape with rounded corners.

Next, a method for producing the case 10 described above will be described. In this method, first, a wire 13 made of a metal wire made of aluminum or an aluminum alloy and having a predetermined thickness is set in a parts former 20 (see FIG. 6). Here, the wire 13 set in the parts former 20 may be a spirally wound wire or a linear bar.

Subsequently, as shown in FIG. 6, the parts former 20 on which the wire 13 is set is operated. The parts former 20 repeats the step of drawing the wire 13 into a cutting device 20A provided in the parts former 20 and cutting the wire 13 to produce the billet 12 . At this time, the billet 12 has a predetermined distance (that is, height) between a cut end 12C on the tip side (upper side in FIG. 6) of the wire rod 13 and a cut end 12A on the opposite side (lower side in FIG. 6) to the cut end 12C. It forms an oblique cylinder that takes values.

Also, as shown in FIG. 7, the parts former 20 inserts the billet 12 produced by cutting the wire 13 into a cylindrical hole 25A provided in the die 25, and the cut end 12A of the billet 12 is the bottom of the hole 25A. 25B side (lower side in FIG. 7) is set. Then, the parts former 20 presses the cut end 12C of the billet 12 with a punch 25E from the opening side (upper side in FIG. 7) of the hole 25A, thereby shaping the billet 12. As shown in FIG. In the present embodiment, the parts former 20 performs the above steps in an ambient temperature environment, thereby performing the steps by cold forging.

Here, the bottom 25B of the hole 25A of the die 25 is provided with a chamfering slope 25D forming an annular curved surface along the edge. Therefore, the billet 12 pressed by the punch 25E is shaped by rounding the edge 12B at the cut end 12A on the side of the bottom 25B by pressing the imposition slope 25D. Hereinafter, the billet 12 whose edge 12B is rounded and shaped is referred to as an "intermediate work 14". That is, the above step can be said to be a step of producing the intermediate work 14 by rounding the edge 12B of the cut end 12A of the billet 12 by surface pressing. Further, it can be said that the billet 12 is a material to be molded into the intermediate work 14 .

A knockout 25C is provided at the bottom 25B of the hole 25A of the die 25 and forms a bar that is slidable in the axial direction of the hole 25A (vertical direction in FIG. 7). After the punch 25E finishes pressing the billet 12, the knockout 25C slides toward the mouth of the hole 25A (upper side in FIG. 7) to eject the produced intermediate work 14 out of the hole 25A. At this time, the discharged intermediate work 14 is held by a transfer device (not shown) of the parts former 20 and turned upside down.

The parts former 20 performs each step from setting the billet 12 in the hole 25A of the die 25 to discharging the shaped intermediate work 14 out of the hole 25A by cutting the wire rod 13 to form the billet 12. It is executed repeatedly in synchronization with the production step (see FIG. 6).

8, the part former 20 inserts the intermediate work 14 discharged out of the hole 25A (see FIG. 7) into the cylindrical hole 26A provided in the die 26, and inserts the intermediate work 14 into the hole 26A. The cut end 12C is placed in a state in which the bottom 26B side (lower side in FIG. 8) of the hole 26A faces and is set. Then, the parts former 20 presses the cut end 12A of the intermediate work 14 with a punch 26E from the mouth side (upper side in FIG. 8) of the hole 26A, thereby shaping the intermediate work 14. As shown in FIG. In the present embodiment, the parts former 20 performs the above steps in an ambient temperature environment, thereby performing the steps by cold forging.

Here, the bottom 26B of the hole 26A of the die 26 is provided with a chamfering slope 26D forming an annular curved surface along the edge thereof. For this reason, the intermediate work 14 pressed by the punch 26E is shaped such that the edge 12D at the cut end 12C on the side of the bottom 26B is rounded by the surface pressing by the imposition slope 26D.

A knockout 26C is provided at the bottom 26B of the hole 26A of the die 26 and forms a bar that can slide in the axial direction of the hole 26A (vertical direction in FIG. 8). After the intermediate work 14 is pressed by the punch 26E, the knockout 26C slides toward the opening of the hole 26A (upper side in FIG. 8), thereby ejecting the intermediate work 14 out of the hole 26A. At this time, the discharged intermediate work 14 is held by a transfer device (not shown) of the parts former 20 and turned upside down.

The parts former 20 performs each step from setting the intermediate work 14 in the hole 26A of the die 26 to discharging the shaped intermediate work 14 out of the hole 26A. is synchronized with each step (see FIG. 7) from setting to discharging the shaped intermediate work 14 out of the hole 25A, and repeatedly executed.

9, the part former 20 inserts the intermediate work 14 discharged out of the hole 26A (see FIG. 8) into the cylindrical hole 27A provided in the die 27, and inserts the intermediate work 14 into the hole 27A. The cut end 12A is placed in a state in which the bottom 27B side (lower side in FIG. 9) of the hole 27A faces and is set. Then, the parts former 20 presses the cut end 12C of the intermediate work 14 with the punch 27E from the opening side (upper side in FIG. 9) of the hole 27A, thereby shaping the intermediate work 14. As shown in FIG. In the present embodiment, the parts former 20 performs the above steps in an ambient temperature environment, thereby performing the steps by cold forging.

Here, the bottom 27B of the hole 27A of the die 27 is provided with a chamfering slope 27D forming an annular curved surface along the edge thereof. Therefore, the edge 12B of the intermediate work 14 pressed by the punch 27E at the cut end 12A on the side of the bottom 27B is re-rounded and shaped by the surface pressing by the imposition slope 27D.

A knockout 27C is provided at the bottom 27B of the hole 27A of the die 27 and forms a bar that can slide in the axial direction of the hole 27A (vertical direction in FIG. 9). After the intermediate work 14 is pressed by the punch 27E, the knockout 27C slides toward the opening of the hole 27A (upper side in FIG. 7), thereby ejecting the intermediate work 14 out of the hole 27A. At this time, the discharged intermediate work 14 is held by a transfer device (not shown) of the parts former 20 and turned upside down.

The parts former 20 performs each step from setting the intermediate work 14 in the hole 27A of the die 27 to discharging the shaped intermediate work 14 out of the hole 27A. 14 is set to discharge the shaped intermediate work 14 out of the hole 26A (see FIG. 8).

10, the part former 20 inserts the intermediate work 14 discharged out of the hole 27A (see FIG. 9) into the cylindrical hole 24A provided in the die 24. The cut end 12C is placed in a state in which it faces the bottom 24B side of the hole 24A (lower side in FIG. 10) and set. Then, the parts former 20 presses the cut end 12A of the intermediate work 14 with a punch 23 from the opening side of the hole 24A (upper side in FIG. 10), thereby forming the intermediate work 14 into the final work 11. FIG. In the present embodiment, the parts former 20 performs the above steps in an ambient temperature environment, thereby performing the steps by cold forging.

Here, the bottom 24B of the hole 24A of the die 24 is provided with a chamfer slope 24D forming an annular surface along the edge. For this reason, the edge 12D of the intermediate work 14 pressed by the punch 23 at the cut end 12C on the side of the bottom 24B is formed into the pedestal portion 11D by pressing by the imposition slope 24D.

A pressing surface 23A of the punch 23 forms a single smooth curved surface (for example, a cylindrical surface in this embodiment) having a height difference in the pressing direction of the punch 23 (vertical direction in FIG. 10). Therefore, the intermediate work 14 pressed by the punch 23 is formed by backward extrusion molding, and the shape corresponding to the curved surface of the pressing surface 23A is transferred to the cut end 12A, thereby forming the first portion 11B and the second portion 11C. is formed into a final workpiece 11 having From this, it can be said that the intermediate work 14 is the material to be molded into the final work 11 . Further, it can be said that the pressing surface 23A of the punch 23 has a shape corresponding to the first portion 11B and the second portion 11C. Moreover, the punch 23 can be said to correspond to the "second punch" in the present invention. When the shape corresponding to the curved surface of the pressing surface 23A is transferred to the cut surface 12A, the cut surface 12A is formed on the curved surface 11K of the final work 11, and the edge 12B of the cut surface 12A is the edge of the curved surface 11K of the final work 11. It is shaped into an edge 11L which is a part.

A knockout 24C is provided at the bottom 24B of the hole 24A of the die 24 and forms a bar that is slidable in the axial direction of the hole 24A (vertical direction in FIG. 10). The knockout 24C slides toward the mouth of the hole 24A (upper side in FIG. 10) after the intermediate work 14 is pressed by the punch 23, thereby ejecting the formed final work 11 out of the hole 24A. At this time, the discharged final work 11 is held by a transfer device (not shown) of the parts former 20 .

The parts former 20 performs each step from setting the intermediate work 14 in the hole 24A of the die 24 to ejecting the formed final work 11 out of the hole 24A. 14 is set to eject the shaped intermediate work 14 out of the hole 27A (see FIG. 9).

18, the parts former 20 sets the final workpiece 11 ejected out of the hole 24A (see FIG. 10) to the die 22. As shown in FIG. The die 22 is a perforated metal member having a cylindrical hole 22A extending in one predetermined direction (vertical direction in FIG. 18). Here, the cylindrical shape of the hole 22A corresponds in size and shape to the outer surface 10D of the case 10 (see FIG. 5). The final workpiece 11 has its axial direction (that is, the axial direction of the disk of the main body portion 11A) aligned with one direction in which the hole 22A extends, and its platform portion 11D faces the bottom 22B side of the hole 22A (in FIG. 18, It is set in the die 22 by being placed in the hole 22A in a posture facing downward).

Then, the parts former 20 presses the curved surface 11K of the final work 11 with the punch 21 from one direction in which the hole 22A extends (more specifically, the opening side of the hole 22A, the upper side in FIG. 18), thereby forming the final work 11. A case 10 is formed by molding. Here, as shown in FIGS. 18 to 20, the punch 21 is provided with a pressing portion 21A forming a projection, and in a state projecting radially outward from the root portion of the projection formed by the pressing portion 21A. It is a punch member provided with a stepped portion 21B.

The stepped portion 21B has a cylindrical shape with a size that allows a loose fit, which is a fit that can be smoothly inserted into the cylinder formed by the hole 22A (see FIG. 18). The pressing portion 21A has a two-sided shape corresponding to the inner surface 10C (see FIG. 18) of the case 10, and the major axis of this two-sided shape is a cylindrical shape formed by the hole 22A (see FIG. 18). A protrusion of a size smaller than the inner diameter of the Therefore, the punch 21 realizes the molding of the final workpiece 11 into the case 10 by backward extrusion molding. That is, the punch 21 corresponds to the "first punch" in the present invention.

Here, when the punch 21 presses the final work 11 from one direction in which the hole 22A extends, the punch 21 presses the final work 11 with its pressing portion 21A, as shown in FIG. In addition, the longitudinal direction of the two-sided shape formed by the pressing portion 21A of the punch 21 is made to match the direction in which the two second portions 11C sandwich the body portion 11A (horizontal direction in FIG. 18). Further, a stepped portion 21B is brought into contact with the axial side (upper side in FIG. 18) end of the final work 11 formed by the pressing of the punch 21, thereby shaping this end.

A knockout 22C is provided at the bottom 22B of the hole 22A of the die 22 and forms a bar that is slidable in the axial direction of the hole 22A (vertical direction in FIG. 18). The knockout 22C slides toward the opening of the hole 22A (upper side in FIG. 18) after the final workpiece 11 is pressed by the punch 21, thereby ejecting the molded case 10 out of the hole 22A. At this time, the ejected case 10 is held by a transfer device (not shown) of the parts former 20 and transported to the outside of the parts former 20 .

The parts former 20 performs each step from setting the final work 11 in the hole 22A of the die 22 to discharging the formed final work 11 out of the hole 22A. 14 is set to eject the final molded work 11 out of the hole 24A (see FIG. 10). Further, the parts former 20 performs each of the above steps in an ambient temperature environment, and presses the final workpiece 11 with the punch 21 to form the case 10 by cold forging.

According to the method for producing the case 10 described above, the height 11E of the first portion 11B, which will be the thick portion 10B, is made lower than the height 11F of the second portion, which will be the thin portion 10A, and the case 10 will be subjected to backward extrusion molding. It is possible to offset the effect of the difference in the amount of elongation in , thereby making the end surface formed by this elongation flatter.

Further, according to the above-described method for producing the case 10, the end face formed by the elongation of the case 10 to be produced is shaped by the stepped portion 21B of the punch 21, thereby shaping the end face. can be made flatter.

In addition, according to the above-described method for producing the case 10, the end surfaces of the produced case 10 formed by the elongation of the rearward extrusion molding can be made smooth, thereby facilitating flattening of the end surfaces. can.

Further, according to the method of producing the case 10 described above, the curved surface 11K of the final workpiece 11 forms a flat curved surface. Therefore, when the curved surface 11K of the final work 11 sticks to the pressing surface 23A of the punch 23 during the production of the final work 11, by applying a force in a specific direction along the pressing surface 23A to the final work 11, This final workpiece 11 can be separated from the punch 23 .

Further, according to the above-described method for producing the case 10, the case 10 having the thin portion 10A and the thick portion 10B can be molded while the projection of the pressing portion 21A is formed in a relatively simple shape of a two-sided chamfer shape. Further, the centering of the punch 21 can be facilitated.

Further, according to the method for producing the case 10 described above, the first portion 11B and the second portion 11C of the final work 11 are formed by transferring the shape corresponding to the pressing surface 23A of the punch 23, thereby forming the final work. 11 can be simplified.

Further, according to the above-described method for producing the case 10, the edge 12D of the cut end 12A of the intermediate work 14 is rounded before being pressed by the punch 23, so that the edge 12D may be crushed by this pressing to form a burr. can be reduced.

Moreover, according to the method of producing the case 10 described above, the case 10 is produced as a product formed by cold forging aluminum or an aluminum alloy. As a result, the case 10 to be produced can have the merits of the cold forged product, such as less dimensional variation due to heat influence.

Further, according to the method for producing the case 10 described above, the case 10 can be produced by a simple operation of setting the wire rod 13 in the parts former 20 and operating the parts former 20 .

Further, according to the final workpiece 11 described above, the height 11E of the first portion 11B, which is the thick portion 10B, is made lower than the height 11F of the second portion, which is the thin portion 10A, so that the amount of elongation of these portions is reduced. It is possible to offset the influence of the difference in the thickness, thereby making the end surface of the case 10 to be formed flatter.

In addition, according to the final work 11 described above, the end surfaces of the produced case 10 formed by the elongation of the rearward extrusion molding can be made smooth, thereby facilitating flattening of the end surfaces.

<Second embodiment>
Next, a method for producing a case according to the second embodiment will be described. A method for producing a case according to the second embodiment is a modification of the method for producing a case according to the first embodiment. Therefore, for configurations that appear in common with the method for producing a case according to the first embodiment, reference numerals obtained by adding "20" to the reference numerals assigned to these configurations are added to correspond to the configurations. detailed description is omitted.

In the method of manufacturing the case according to the second embodiment, as shown in FIG. 21, the final workpiece 11 (see FIG. 18) has a single curved surface 11K at the end surface pressed by the pressing portion 21A of the punch 21. Instead, the final work 31 having a preliminary hole 31M in the portion pressed by the pressing portion 41A of the punch 41 is used. The final workpiece 31 is pressed by the pressing portion 41A of the punch 41 (corresponding to the "first punch" in the present invention) of the parts former 40, and thus has the same shape as the case 10 (see FIG. 18). It is extruded backwards into the presenting case 30 . Here, the pressing portion 41A of the punch 41 forms a two-sided projection corresponding to the inner side surface 30C of the case 30. As shown in FIG.

As shown in FIGS. 23 to 28, the preliminary hole 31M of the final work 31 is provided on the main body 31A of the final work 31 on the opposite side of the platform 31D. The preliminary hole 31M is a two-sided hole corresponding to the pressing portion 41A of the punch 41, and its size is such that it can be loosely fitted to the pressing portion 41A (see FIG. 21). See virtual line). In other words, the preliminary hole 31M is a hole having a size and shape that allows a loose fit with the pressing portion 41A. In the present embodiment, the longitudinal direction of the preliminary hole 31M of the final work 31 is the direction in which the two second portions 31C of the final work 31 sandwich the body portion 31A (vertical direction in FIG. 24). provided to match the

Here, as shown in FIG. 22, the final work 31 is prepared by molding an intermediate work 34, which is a material to be molded into the final work 31, by backward extrusion molding. That is, the intermediate work 34 is set in a cylindrical hole 44A provided in the die 44 of the parts former 40, and pressed by a punch 43 (corresponding to the "second punch" in the present invention), The final workpiece 31 is extruded backward. Here, the punch 43 has a pressing surface 43A that presses the intermediate work 34 and has unevenness corresponding to the first portion 31B, the second portion 31C, and the preliminary hole 31M. is transferred to the cut end 32A. As a result, the final workpiece 31 to be formed is provided with the first portion 31B, the second portion 31C, and the preliminary hole 31M.

When the final workpiece 31 is molded into the case 30, as shown in FIG. 21, a metal body having a cylindrical hole 42A extending in one predetermined direction (vertical direction in FIG. 21) is formed. A final work 31 is set on a die 42 which is a perforated member. At this time, the axial direction of the final work 31 (that is, the axial direction of the disc of the body portion 31A) coincides with one direction in which the hole 42A of the die 42 extends, and the platform portion 31D of the final work 31 is positioned on the bottom 42B side of the hole 42A (Fig. 21 is put into this hole 42A in a posture facing downward).

In the parts former 40, the longitudinal direction of the two-sided shape formed by the pressing portion 41A of the punch 41 (horizontal direction in FIG. 18) is the same as the longitudinal direction of the two-sided shape formed by the preliminary hole 31M of the final work 31. The punch 41 is put into the hole 42A of the die 42 in a matching condition. Then, the parts former 40 inserts the pressing portion 41A of the punch 41 into the preliminary hole 31M of the final work 31, and pushes the bottom of the preliminary hole 31M in one direction in which the hole 42A extends (specifically, the mouth side of the hole 42A, FIG. 21). The case 20 is formed by pressing with a punch 41 from the upper side as viewed in FIG. In other words, the parts former 40 inserts the pressing portion 41A of the punch 41 into the preliminary hole 31M of the final work 31 when the punch 41 presses the final work 31 from the one direction.

According to the method for producing the case 30 described above, when the case 30 is produced by rearward extrusion, the looseness of the final workpiece 31 is suppressed by the fitting between the preliminary hole 31M and the pressing portion 41A of the punch 41. The shape accuracy of the produced case 30 can be improved. Further, since the fit is a clearance fit, the pressing portion 41A of the punch 41 can be smoothly inserted into the preliminary hole 31M.

The present invention is not limited to the appearance and configuration described in the first and second embodiments described above, and various modifications, additions, and deletions are possible without changing the gist of the present invention. For example, the following various forms can be implemented.

(1) The method of producing the case of the present invention is not limited to the method of producing a bottomed cylindrical case having a cylindrical outer surface and a two-sided inner surface. That is, the method for producing a case of the present invention can be used to produce a case having a non-cylindrical outer surface, such as a case having a knob-like projection on the outer surface. In addition, the method for producing the case of the present invention uses a punch member having a pressing portion having a shape other than a two-sided shape, such as a truncated pyramid shape or a cylindrical shape, and presses the inner surface of the shape corresponding to the shape. can be used in producing a case with Here, when the pressing portion of the punch member has a straight columnar shape having an oval bottom surface with a longer diameter smaller than the inner diameter of the die hole, when pressing the final workpiece with this punch, the two It is preferable that the direction in which the second portion sandwiches the main body portion coincides with the longitudinal direction of the oval shape. In this case, it is possible to form a case having a thin portion and a thick portion while forming the protrusion of the pressing portion into a relatively simple straight column shape having an oval bottom surface.

(2) The method of producing the case of the present invention is not limited to a series of steps executed by operating one parts former in which a wire rod is set. That is, the method for producing the case of the present invention can be executed by, for example, a tandem press system combining a plurality of press devices. In addition, the method of producing the case of the present invention is carried out by combining a machining center that cuts out a final workpiece of a desired shape from a metal ingot and a pressing device that forms the final workpiece by backward extrusion to form a case. be able to.

(3) The method of producing the case of the present invention is not limited to cold forging a wire made of aluminum or an aluminum alloy. That is, the method of producing the case of the present invention may work with metals that are neither aluminum nor aluminum alloys, such as brass, phosphor bronze, or iron. In addition, the method for producing the case of the present invention can process the metal by warm forging or hot forging.

10 Case 10A Thin portion 10B Thick portion 10C Inner surface 10D Outer surface 11 Final workpiece 11A Body portion 11B First portion 11C Second portion 11D Trapezoidal portion 11E Height 11F Height 11G End surface 11H Symmetrical surface 11J End surface 11K Curved surface 11L edge 12 billet 12A cut end 12B edge 12C cut end 12D edge 13 wire 14 intermediate work 20 parts former 20A cutting device 21 punch (first punch)
21A pressing portion 21B stepped portion 22 die 22A hole 22B bottom 22C knockout 23 punch (second punch)
23A pressing surface 24 die 24A hole 24B bottom 24C knockout 24D imposition slope 25 die 25A hole 25B bottom 25C knockout 25D imposition slope 25E punch 26 die 26A hole 26B bottom 26C knockout 26D imposition slope 26E punch 27 die 27A hole 27B bottom 27C Knockout 27D Face attachment slope 27E Punch 30 Case 30A Thin portion 30B Thick portion 30C Inner side 30D Outer side 31 Final workpiece 31A Main body 31B First part 31C Second part 31D Trapezoidal part 31E Height 31F Height 31G End face 31H Symmetrical surface 31J End surface 31K Curved surface 31L Edge 31M Preliminary hole 32A Cut edge 32B Edge 32C Cut edge 32D Edge 34 Intermediate workpiece 40 Parts former 41 Punch (first punch)
41A pressing portion 41B stepped portion 42 die 42A hole 42B bottom 42C knockout 43 punch (second punch)
43A pressing surface 44 die 44A hole 44B bottom 44C knockout 44D chamfering slope

Claims (15)

A thin portion having a relatively thin thickness from the outer surface to the inner surface, comprising a portion forming a cylinder having an inner surface and an outer surface, and a bottom portion closing one end of the cylinder; A method for producing a case in which a thick portion, which is thicker from the outer surface to the inner surface than the thin portion, is arranged along the circumferential direction of the cylinder. hand,
A final work that will be a material to be molded into the case,
a first portion that becomes the thick portion when molded into the case;
a second portion that becomes the thin portion when molded into the case;
and
The height of the first portion seen in the axial direction along which the cylinder extends when the final work is molded into the case is lower than the height of the second portion seen in the axial direction. prepared in such a way that
The final workpiece is placed in the hole in the die having a hole formed in a shape corresponding to the outer surface and extending in a predetermined one direction, and the axial direction of the final workpiece is aligned with the one direction. set to
The final work is pressed from the one direction by a first punch provided with a pressing portion having a projection having a shape corresponding to the inner surface, and the final work is formed by backward extrusion molding to form the case.
How to produce a case. A method of producing a case according to claim 1, comprising:
A punch member provided with the pressing portion and a stepped portion protruding radially outward from the projection formed by the pressing portion is used as the first punch. ,
When the final work is pressed from the one direction by the first punch, the stepped portion is brought into contact with the axial end of the final work formed by the pressing, thereby shaping the end.
How to produce a case. A method of producing a case according to claim 1 or claim 2, comprising:
the final work,
a main body forming a disc;
a pedestal formed as a solid pedestal at the end that will be the bottom side of the hole when the final work is set in the hole of the die;
has
The two second portions are provided on the sides of the disk formed by the main body so as to sandwich the disk from the radial direction thereof,
The two first portions are provided at a portion sandwiched between the two second portions on the side portion of the disk formed by the body portion, and
A single smooth curved surface straddles the end surfaces of the two first portions that are opposite to the pedestal portions and the end surfaces of the two second portions that are opposite to the pedestal portions. prepared in the state set by
How to produce a case. A method of producing a case according to claim 3, comprising:
said final work,
The end surfaces of the two first portions on the side opposite to the pedestal portion and the end surfaces of the two second portions on the side opposite to the pedestal portion collectively form the curved surface. be prepared to
How to produce a case. A method of producing a case according to claim 3, comprising:
the final work,
A preliminary hole having a size and a shape that allows a loose fit with the pressing portion of the first punch is formed in a portion of the main body portion opposite to the pedestal portion. ready to have,
inserting the pressing portion of the first punch into the preliminary hole when pressing the final work from the one direction with the first punch;
How to produce a case. A method for producing a case according to any one of claims 1 to 5, comprising:
the final work,
having a main body forming a disc, and
preparing a state in which the two second portions are provided on the side portions of the disk formed by the main body so as to sandwich the disk from the radial direction thereof;
using a perforated member having a cylindrical hole as the die,
using as the first punch a punch member having a two-sided shape in which the projection formed by the pressing portion has a longer diameter smaller than the inner diameter of the cylindrical shape;
When the first punch presses the final work from the one direction, the longitudinal direction of the two-sided shape of the first punch is the direction in which the two second portions sandwich the main body. to match,
How to produce a case. A method for producing a case according to any one of claims 1 to 5, comprising:
said final work,
having a main body forming a disc, and
preparing a state in which the two second portions are provided on the side portions of the disk formed by the main body so as to sandwich the disk from the radial direction thereof;
using a perforated member having a cylindrical hole as the die,
using as the first punch a punch member in which the projection formed by the pressing portion has a straight columnar shape having an oval bottom surface with a longer diameter smaller than the inner diameter of the cylindrical shape;
When the final work is pressed from the one direction by the first punch, the longitudinal direction of the elliptical shape of the first punch coincides with the direction in which the two second portions sandwich the main body. to make
How to produce a case. A method of producing a case according to any one of claims 1 to 7, comprising:
The intermediate work, which is the material to be molded into the final work, is pressed by a second punch having a pressing surface having a shape corresponding to the first portion and the second portion, thereby moving the intermediate work backward. Molded by extrusion molding to form the final work,
How to produce a case. A method of producing a case according to claim 8, comprising:
Producing a billet as a material to be molded into the intermediate work by cutting a wire,
producing the intermediate work by rounding the edge of the cut end of the billet by pressing against the surface of the billet;
pressing the cut end of the intermediate work with the second punch to form the intermediate work into the final work;
How to produce a case. A method of producing a case according to claim 9, comprising:
A metal wire made of aluminum or an aluminum alloy is prepared as the wire, and
a step of producing, as the intermediate work, the edge of the cut end of the billet that has been rounded by the surface pressing;
pressing the cut end of the intermediate work with the second punch to form the intermediate work into the final work;
pressing the final work with the first punch to shape the final work into the case;
is carried out by the technique of cold forging,
How to produce a case. A method of producing a case according to claim 9 or claim 10, comprising:
producing said billet by said cutting of said wire;
a step of producing, as the intermediate work, the edge of the cut end of the billet that has been rounded by the surface pressing;
pressing the cut end of the intermediate work with the second punch to form the intermediate work into the final work;
pressing the final work with the first punch to shape the final work into the case;
into a series of steps performed by one parts former,
How to produce a case. A thin portion having a relatively thin thickness from the outer surface to the inner surface, comprising a portion forming a cylinder having an inner surface and an outer surface, and a bottom portion closing one end of the cylinder; The thick portion, which is thicker from the outer surface to the inner surface than the thin portion, is the final work to be the material to be molded into the case set side by side along the circumferential direction of the cylinder. hand,
a main body forming a disc;
two second portions , which are portions that become the thin portion when molded into the case, and are provided on the side portions of the disk formed by the main body so as to sandwich the disk from the radial direction thereof;
Two first portions provided at portions sandwiched between the two second portions on the sides of the disk formed by the main body, which are portions that become the thick portions when molded into the case. part and
a pedestal formed as a solid pedestal on one side of the disk of the main body;
with
the height of the first portion of the disk of the body viewed in the axial direction is lower than the height of the second portion viewed in the axial direction;
final work. A final workpiece according to claim 12, comprising:
One smooth curved surface is the edge of the end surface opposite to the pedestal portion in the two first portions and the end surface opposite to the pedestal portion in the two second portions. is set across the edge of the
final work. A final workpiece according to claim 13, comprising:
The end surfaces of the two first portions on the side opposite to the pedestal portion and the end surfaces of the two second portions on the side opposite to the pedestal portion collectively form the curved surface. are doing,
final work. A final workpiece according to claim 13, comprising:
The final work can be formed into the case by rearward extrusion molding by pressing the final work with a pressing portion having a projection having a shape corresponding to the inner surface,
moreover,
A preliminary hole, which is a hole having a size and shape that allows a loose fit with the pressing portion, is provided in a portion of the main body portion opposite to the pedestal portion,
final work.

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