JP5307211B2 - Press machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a press working apparatus in which occurrence of wear deterioration on a pressure receiving plate is reduced. <P>SOLUTION: This invention is intended for the press working apparatus in which the tip 31 of a punch 3 is pressed against a workpiece in a state where the base end side of the punch 3 is supported by the pressure receiving face 51 of a pressure receiving plate 5. A punch supporting base 6 is formed so as to project on the pressure receiving face 51 of the pressure receiving plate 5 and a punch supporting face 61 which is brought into contact with the base end face 32 of the punch 3 is provided to the punch supporting base 6. The size of the punch supporting face 61 is set so as not to be larger than the size of the base end face 32 of the punch 3. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a press working apparatus that presses a punch against a workpiece and related technology.

  A forging apparatus in which a punch is driven into a workpiece for forging is disclosed in Patent Document 1 and the like.

  In such a forging apparatus, a pressure receiving plate is provided at the upper end of the punch arranged along the vertical direction, and the punch is lowered and driven into the workpiece while the upper end surface of the punch is supported by the pressure receiving plate. Things are well known.

JP-A-9-57386 (Claims, Fig. 3-5)

  In the forging device described above, the impact load at the time of punching is received by the pressure receiving plate through the punch, but since this impact load repeatedly acts on the pressure receiving plate, the punch support portion of the pressure receiving plate is subject to wear. A deteriorated recess is formed. If this deteriorated recess becomes large, the punch cannot be supported in a stable state by the pressure receiving plate, and the processing accuracy is lowered, so the pressure receiving plate needs to be replaced.

  However, in the conventional forging apparatus, the pressure plate is subject to wear deterioration in a short period of time, and the pressure plate is frequently replaced, resulting in a decrease in productivity and an increase in cost.

  The present invention relates to a press working apparatus such as a forging apparatus that can solve the above-described problems of the prior art and can reduce the occurrence of wear deterioration in a pressure receiving plate, and a related technique.

  In order to achieve the above object, the present invention has the following structure.

[1] A press working device that presses the tip of the punch against the work in a state where the base end side of the punch is supported by the pressure receiving surface of the pressure receiving plate,
On the pressure receiving surface of the pressure receiving plate, the punch support base is formed so as to protrude, and the punch support base is provided with a punch support surface in contact with the base end surface of the punch,
A press working apparatus, wherein the size of the punch support surface is set to be equal to or smaller than the size of the base end surface of the punch.

  [2] The press working apparatus according to item 1, wherein the outer peripheral edge of the punch base end face is disposed in a non-contact state with respect to the pressure receiving plate.

  [3] The press working apparatus according to item 1 or 2, wherein the outer peripheral edge of the punch support surface is disposed 0.1 to 0.3 mm inside the outer peripheral edge of the punch base end surface.

  [4] The press working apparatus according to any one of items 1 to 3, wherein the area of the punch support surface is formed to be 0.1 to 0.5% smaller than the area of the punch base end surface.

  [5] The press working apparatus according to any one of items 1 to 4, wherein the height of the punch support base is set to 0.1 to 1.5 mm.

  [6] The press working apparatus according to any one of items 1 to 5, wherein the pressure receiving plate is formed in a truncated cone shape having the pressure receiving surface as a top.

  [7] The press working apparatus according to the above item 6, wherein an inclination angle with respect to the axis of the outer peripheral surface of the pressure receiving plate is set to 20 to 70 °.

  [8] The press according to any one of items 1 to 7, wherein the pressure receiving plate is divided into a plurality of parts, and one of the plurality of divided bodies is configured by a portion including the punch support base portion of the pressure receiving plate. Processing equipment.

  [9] The press working apparatus according to any one of items 1 to 8, wherein a chamfered portion is formed outside the punch support surface in the punch support base portion.

  [10] The press working apparatus according to any one of items 1 to 9, wherein a chamfered portion is formed between a base end surface and an outer peripheral surface of the punch.

[11] A punch holder for holding the punch and the pressure receiving plate is provided.
While the pressure receiving plate is formed in a truncated cone shape with the pressure receiving surface as the top,
The inner peripheral surface of the holding hole for holding the pressure receiving plate in the punch holder is formed following the outer peripheral shape of the pressure receiving plate,
A part of the outer peripheral surface of the pressure receiving plate is provided with an outer peripheral parallel surface parallel to the axial center direction of the punch, and the inner peripheral surface of the holding hole in the punch holder in the axial direction corresponding to the outer peripheral parallel surface. Parallel inner circumferential parallel surface is provided,
11. The press working apparatus according to any one of the preceding items 1 to 10, wherein the pressure receiving plate is accommodated in the holding hole of the punch holder in a state where the outer peripheral parallel surface is fitted to the inner peripheral parallel surface along the axial direction.

[12] On the pressure receiving surface side of the outer peripheral surface of the pressure receiving plate, a concave step portion that is continuous along the circumferential direction is formed, and an outer peripheral parallel surface is configured by one surface of the concave step portion,
Corresponding to the concave step portion, a convex step portion that is continuous along the circumferential direction is formed on the inner peripheral surface of the holding hole in the punch holder, and an inner peripheral parallel surface is constituted by one surface of the convex step portion. 12. The press working apparatus according to item 11 above.

  [13] The press working apparatus according to the above item 11 or 12, wherein a gap is provided between the outer peripheral surface of the pressure receiving plate and the inner peripheral surface of the holding hole of the punch holder.

  [14] Any one of the preceding items 11 to 13, wherein a gap dimension between the outer peripheral parallel surface and the inner peripheral parallel surface is set to be smaller than a distance between the outer peripheral edge of the punch support surface and the outer peripheral edge of the punch base end surface. The press working apparatus according to item 1.

  [15] The press working device according to any one of the above items 11 to 14, wherein a gap dimension between the outer peripheral parallel surface and the inner peripheral parallel surface is set to 0.1 to 0.5 mm.

[16] A cylindrical punch case that accommodates the punch along the axial direction;
16. The press working apparatus according to any one of the preceding items 1 to 15, comprising a punch case and a punch holder for holding a pressure receiving plate.

[17] The base end surface of the punch is disposed closer to the punch front side than the base end surface of the punch case,
17. The press working apparatus according to 16 above, wherein the base end surface of the punch case is disposed in contact with the outside of the punch support base portion on the pressure receiving surface of the pressure receiving plate.

  [18] A press working method comprising pressing a workpiece using the press working apparatus according to any one of 1 to 17 above.

[19] A die set that presses the tip of the punch against the work set on the die in a state where the base end side of the punch is supported by the pressure receiving surface of the pressure receiving plate,
On the pressure receiving surface of the pressure receiving plate, the punch support base is formed so as to protrude, and the punch support base is provided with a punch support surface in contact with the base end surface of the punch,
A die set, wherein the size of the punch support surface is set to be equal to or smaller than the size of the base end surface of the punch.

[20] A forging device that forges the workpiece by pressing the tip of the punch against the workpiece while the base end side of the punch is supported by the pressure receiving surface of the pressure receiving plate,
On the pressure receiving surface of the pressure receiving plate, the punch support base is formed so as to protrude, and the punch support base is provided with a punch support surface in contact with the base end surface of the punch,
A forging apparatus characterized in that the size of the punch support surface is set to be equal to or smaller than the size of the base end surface of the punch.

[21] An upper die for press working that presses the lower end portion of the punch against the work in a state where the upper end side of the punch arranged along the vertical direction is supported by the lower surface of the pressure receiving plate,
A punch support surface is formed on the lower surface of the pressure receiving plate so as to protrude, and the punch support surface is provided with a punch support surface in contact with the upper end surface of the punch.
An upper die for press working, wherein the size of the punch support surface is set to be equal to or smaller than the size of the upper end surface of the punch.

[22] A pressure receiving plate for press working that has a pressure receiving surface that supports the base end side of the punch, and presses the tip of the punch against the work in a state where the punch is supported by the pressure receiving surface,
The pressure receiving surface is formed so that the punch support base protrudes, and the punch support base is provided with a punch support surface in contact with the base end surface of the punch,
A pressure receiving plate for press working, wherein a size of a punch support surface is set to be equal to or smaller than a size of a base end surface of the punch.

  According to the press processing apparatus of the invention [1], since the punch support surface formed on the pressure receiving plate is set to be equal to or smaller than the size of the punch base end surface, the impact load during the press processing is not on the pressure receiving plate side, Concentrate on the punch side. For this reason, wear deterioration occurs on the punch base end face side, and occurrence of wear deterioration on the pressure receiving plate side can be reduced.

  Note that since the tip of the punch (pressing portion) is worn out and deteriorated at an early stage, this wear at the tip of the punch becomes a factor for replacing the punch. Therefore, the wear of the punch base end face according to the present invention does not become a factor for exchanging the punch, and no trouble is caused by the wear of the punch base end face.

  According to the press processing apparatus of the invention [2] to [5], the above effect can be obtained more reliably.

  According to the press processing apparatus of the invention [6], the impact at the time of press processing propagates while gradually spreading along the frustoconical pressure receiving plate, so that the impact load can be dispersed over a wide range, Can prevent problems due to local concentration.

  According to the press processing apparatus of the invention [7], the impact load can be more reliably dispersed.

  According to the press working apparatus of the invention [8], when wear deterioration occurs in the punch support base portion of the pressure receiving plate, only the portion including the punch support base portion can be replaced, and the replacement site can be reduced. .

  According to the press working apparatus of the invention [9] [10], occurrence of wear deterioration can be surely reduced.

  According to the press processing apparatus of the invention [11] to [15], the outer peripheral parallel surface of the pressure receiving plate is positioned to be parallel to the inner periphery of the punch holder, thereby aligning the pressure receiving plate with the punch holder (centering). It can be performed with high accuracy.

  According to the press processing apparatus of the inventions [16] and [17], the punch is restrained by the punch case, so that the punch can be prevented from swinging and the processing accuracy and product quality can be further improved.

  According to the invention [18], it is possible to provide a press working method having the same effect as the above.

  According to the invention [19], it is possible to provide a die set having the same function and effect as described above.

  According to the invention [20], it is possible to provide a forging device having the same effect as described above.

  According to the invention [21], it is possible to provide an upper die for press working having the same effect as the above.

  According to the invention [22], it is possible to provide a pressure receiving plate for press working having the same effect as the above.

It is a front view which shows the forge processing apparatus of embodiment of this invention. It is sectional drawing which shows the die set periphery of the forge processing apparatus of embodiment of this invention. It is sectional drawing which shows the upper metal mold | die of the forge processing apparatus in embodiment. It is sectional drawing which expands and shows the principal part of the upper metal mold | die in embodiment. It is a side view which shows the punch in the upper metal mold | die of embodiment. It is sectional drawing which shows the punch case in the upper metal mold | die of embodiment. It is sectional drawing which shows the punch case in the upper metal mold | die of embodiment in a punch accommodation state. It is a perspective view shown in the state where the 1st division object of the pressure receiving plate in the upper metallic mold of an embodiment was turned upside down. It is a bottom view which shows the 1st division body in the pressure receiving plate of embodiment. It is sectional drawing which shows the 1st division body in the pressure receiving plate of embodiment. It is sectional drawing which shows the 2nd division body in the pressure receiving plate of embodiment. It is sectional drawing which shows the punch holder in the upper metal mold | die of embodiment. It is a schematic sectional drawing which exaggerates the characteristic part around the contact part of the pressure receiving plate and punch in the upper metal mold | die of embodiment. It is a schematic sectional drawing which exaggerates the fault part around the contact part of the pressure receiving plate and punch in the upper metallic mold which deviates from the gist of the present invention. It is a top view which shows the forged product produced with the forge processing apparatus of embodiment. It is sectional drawing which shows the forged product produced by the forge processing apparatus of embodiment. It is sectional drawing which shows the upper metal mold | die of the forge processing apparatus which is a modification of this invention.

  1 and 2 are views showing a forging device (1) according to an embodiment of the present invention. As shown in the figure, the forging device (1) includes a lower die (11) as a fixed die and an upper die (15) as a movable die.

  The lower mold (11) is provided with a die (2). The die (2) is provided with a die hole (25) whose axis is arranged along the vertical direction, and a workpiece (W) as a forging material (workpiece) is provided in the die hole (25). ) Can be set.

  In the die hole (25), there is provided a knockout pin (22) that can protrude upward in a state where the axis is aligned with the axis of the die hole (25). And the product after the shaping | molding process arrange | positioned by this knockout pin (22) at the die hole (25) is pushed up, and is discharged | emitted from a die hole (25).

  The lower mold (11) is fixed to the lower mold base (12) of the forging device (1) with the die hole (25) facing upward.

  The upper mold (15) includes a punch (3), a punch case (4), a pressure receiving plate (5), and a punch holder (7) as basic components.

  As shown in FIGS. 2 to 5, the punch (3) has a substantially cylindrical shape, the lower end surface (31) constituting the distal end surface is formed as a pressing surface, and the upper end surface constituting the proximal end surface (32) is formed on a flat surface (horizontal surface) so as to be in contact with and supported by the pressure receiving plate (5).

  On the upper end of the outer peripheral side surface of the punch (3), a retaining portion (36) is formed integrally and continuously in the circumferential direction so as to project outward. Further, a chamfered portion (37) is formed between the upper end surface (32) of the punch (3) and the outer peripheral surface of the retaining portion (36).

  The punch (3) is made of a material such as stainless steel, carbon steel, or cemented carbide.

  As shown in FIGS. 6 and 7, the punch case (4) has a punch holding hole (45) for accommodating the punch (3). In the punch holding hole (45), a concave step portion (456) is continuously formed in the upper end portion thereof corresponding to the retaining portion (36) of the punch (3) in the circumferential direction. 3) can be accommodated in conformity.

  Further, a retaining part (46) is formed integrally and continuously in the circumferential direction on the outer peripheral surface of the punch case (4) so as to project outward.

  In the state where the punch (3) is accommodated in the holding hole (45) of the punch case (4), the inner peripheral surface of the concave step portion (456) in the punch holding hole (45) is the retaining portion ( 36) The position of the punch case (4) is regulated by being in contact with the outer circumferential surface of 36) and the position of the inner circumferential surface of the lower end (451) being in contact with the outer circumferential surface of the intermediate portion of the punch (3). On the other hand, centering (centering) of the punch (3) is performed. A gap is formed between the inner peripheral surface of the punch holding hole (45) other than the upper end portion (456) and the lower end portion (451) (intermediate region) and the outer peripheral surface of the punch (3).

  Further, the lower end corner portion of the retaining portion (36) in the punch (3) engages with the lower end corner portion of the recessed step portion (456) in the punch holding hole (45), so that the punch (3) is moved to the punch case ( In contrast to 4), it is prevented from coming out downward.

  Further, when the punch (3) is housed in the punch case (4), the upper end surface (32) of the punch (3) is lower than the upper end surface (42) of the punch case (4), as will be described in detail later. It is supposed to be arranged in.

  As shown in FIGS. 3, 4, and 8 to 11, the pressure receiving plate (5) is configured by a first and second divided bodies (501) and (502) that can be divided. The first divided body (501) constitutes the lower end portion (pressure receiving surface side) of the pressure receiving plate (5), and the second divided body (502) constitutes the upper portion excluding the lower end portion of the pressure receiving plate (5). doing. In this embodiment, each divided body (501) (502) is made of, for example, a material such as stainless steel, carbon steel, or carbide steel, and the same material as the punch (3) is usually used.

  The pressure receiving plate (5) is formed in a substantially truncated cone shape in which the lower surface (51) constituting the pressure receiving surface is the top, that is, in a substantially truncated cone shape in which the lower end portion has a smaller outer diameter than the upper end portion. The outer peripheral surface is formed as a tapered surface (53) so as to be inclined with respect to the axis (C).

  On the outer periphery of the upper end portion of the pressure receiving plate (5), a retaining portion (56) is formed integrally and continuously in the circumferential direction so as to project outward. In addition, the outward outer peripheral surface of the retaining portion (56) is arranged in parallel to the axis (C).

  On the outer periphery of the lower end portion of the pressure receiving plate (5), a concave step portion (57) formed so as to be cut out in an L shape is continuously formed in the circumferential direction. The concave step (57) has an orthogonal surface (571) orthogonal to the axis (C) and an outer peripheral parallel surface (573) parallel to the axis (C).

  On the lower surface (51) of the pressure receiving plate (5), a circular punch support base (6) protrudes downward (axial direction) so that the axial center (C) coincides with the pressure receiving plate (5). Are integrally formed. The outer peripheral surface of this punch support base part (6) is comprised as an inclined surface which inclines inside, and comprises the chamfering part (67).

  The punch support surface (61) constituted by the lower surface (top surface) of the punch support base (6) has an outer diameter dimension set to be equal to or smaller than the outer diameter dimension of the punch upper end surface (32), as will be described in detail later. ing.

  As shown in FIG. 12, the punch holder (7) has a holding hole (75) formed following the outer peripheral shape of the pressure receiving plate (5), and the pressure receiving plate (5) is formed in the holding hole (75). Can be accommodated in conformity.

  That is, the inclination angle of the inner peripheral tapered surface (73) of the holding hole (75) with respect to the axis (C) coincides with the inclination angle of the outer peripheral tapered surface (53) of the pressure receiving plate (5) with respect to the axis (C). It is formed to do.

  Further, on the inner periphery of the upper end portion of the holding hole (75), a concave step portion (756) is continuously formed in the circumferential direction corresponding to the retaining portion (56) of the pressure receiving plate (5). The inward inner peripheral surface of the concave step (756) is arranged in parallel to the axis (C).

  A convex step portion (77) is formed on the inner periphery of the intermediate portion of the holding hole (75) so as to protrude inward, corresponding to the concave step portion (57) of the pressure receiving plate (5). The convex step portion (77) has an orthogonal surface (772) orthogonal to the axis (C) and an inner peripheral parallel surface (773) parallel to the axis (C).

  Further, a concave step portion (757) is continuously formed in the circumferential direction corresponding to the retaining portion (46) of the punch case (4) on the lower inner periphery of the holding hole (75).

  Further, a mounting step (76) is formed continuously in the circumferential direction at an intermediate portion of the outer peripheral surface of the punch holder (7).

  3 and 4, the punch case (4) containing the punch (3) is received in the holding hole (75) of the punch holder (7), and from above the punch (3), The first divided body (501) and the second divided body (502) of the pressure receiving plate (5) are sequentially accommodated.

  In this accommodated state, the lower end corner portion of the retaining portion (46) in the punch case (4) is engaged with the lower end corner portion of the concave step portion (757) on the inner peripheral surface of the holding hole of the punch holder (7). This prevents the punch case (4) from coming out downward with respect to the punch holder (7). Furthermore, the outer peripheral surface of the punch case (4) (including the outer peripheral surface of the retaining portion 46) is the inner peripheral surface of the holding hole (75) in the punch holder (7) (including the inner peripheral surface of the recessed step portion 757). The centering of the punch case (4) is performed with respect to the punch holder (7) by being regulated by contact.

  Further, in a state where the second divided body (502) is in contact with the upper surface of the first divided body (501) of the pressure receiving plate (5), the punch supporting surface (61) of the pressure receiving plate (5) is moved to the punch (3 ) In contact with the upper end surface (32) of the punch support (6) on the lower surface (51) of the pressure receiving plate (5) and the upper end surface (42) of the punch case (4). Has been placed.

  Here, in this embodiment, the difference in height position between the upper end surface (42) of the punch case (4) and the upper end surface (32) of the punch (3) is the punch support base portion on the pressure receiving plate lower surface (51). This corresponds to the height (H) of (6).

  Further, the outer peripheral parallel surface (573) of the concave step portion (57) at the lower end of the pressure receiving plate (5) is the inner peripheral parallel surface (773) of the convex step portion (77) at the holding hole intermediate portion of the punch holder (7). The outer peripheral surface of the retaining portion (56) at the upper end portion of the pressure receiving plate (5) is positioned on the concave step portion (756) at the upper end portion of the holding hole of the punch holder (7). The position of the pressure receiving plate (5) is centered with respect to the punch holder (7) by being regulated in contact with the inward inner peripheral surface.

  As shown in FIG. 2, the upper mold (15) having the above configuration is fixed to the upper mold base (16) of the forging device (1) through the fastening holder (81) and the fastening ring (82). The

  That is, the fastening holder (81) has a mounting hole (815) into which the punch holder (7) of the upper mold (15) can be inserted, and a flange (816) is formed on the upper end of the outer peripheral portion so as to project outward. Has been. And this flange (816) is being fixed to the upper metal mold | die base (16) via the fixing tool (85).

  The fastening ring (82) has a mounting hole (825) through which the lower side portion of the punch holder (7) can be inserted. Furthermore, the fastening ring (82) has the outer peripheral wall part (823) arrange | positioned at the outer peripheral part of a fastening holder (81).

  And the lower side part of the punch holder (7) in the upper mold (15) is inserted and arranged in the mounting hole (825) of the fastening ring (82) from above. Further, the upper portion of the punch holder (7) is inserted from below into the mounting hole (815) of the fastening holder (81), and in this state, the inner peripheral thread portion of the fastening ring (82) is inserted into the punch holder (7). The upper die (15) is fixed to the die base (16) via the fastening holder (81) and the fastening ring (82). In this fixed state, the upper mold (15) is pulled out downward by the mounting step (76) on the outer peripheral surface of the punch holder (7) engaging the peripheral edge of the mounting hole of the fastening ring (82). Is prevented.

  In FIG. 2, reference numeral (83) denotes an insert plate provided on the upper mold base (16) corresponding to the upper surface of the upper mold (15).

  The assembling procedure of the upper die (15) in the forging device (1) having the above configuration is as follows. First, after the punch (3) is accommodated in the punch case (4), the punch case (4) is set in the punch holder (7), and the pressure receiving plate (5) is set in the punch holder (7). Assemble the upper die (15).

  Subsequently, the upper mold (15) is fixed to the fastening holder (81) of the upper mold base (16) via the fastening ring (82).

  In the forging device (1) having the above configuration, the upper die (15) is configured to be movable up and down, and the workpiece (W) is set in the die hole (25) of the lower die (11). In this state, the upper die base (16) is lowered together with the upper die (15) to press the punch (3) of the upper die (15) against the work (W) in the die hole (25). The workpiece (W) is plastically deformed and forged into a predetermined shape.

  Here, as shown in FIGS. 15 and 16, the molded product (W1) obtained by the forging device (1) of the present embodiment has a bottomed cylindrical cup shape with the upper end opened and the lower end closed. Formed.

  In the present embodiment, as the material of the forging material (work W), various types of conventionally known metals can be used. For example, aluminum, iron, copper, brass, magnesium, or alloys thereof are preferably used. it can. In particular, for the purpose of weight reduction, it is preferable to use aluminum or an alloy thereof, for example, an alloy having an alloy symbol of 2000, 3000, 4000, 5000, 6000, or 7000 can be suitably used.

  Any processing method such as continuous casting, extrusion, or rolling can be used as a method for producing a round bar material for a workpiece material. Further, when a round bar made of aluminum or its alloy is used, the round bar made by continuous casting can be suitably used because it is readily available and inexpensive. In particular, in aluminum alloys, round bar material (“SHOTIC material (registered trademark)” manufactured by Showa Denko Co., Ltd.) continuously cast by the gas pressure hot top casting method has excellent internal soundness and crystal grains. Since it is fine and there is no crystal grain anisotropy due to plastic working, the resistance effect of the frictional resistance portion can be obtained stably, so that it can be used more suitably.

  A round bar is used after being cut into a predetermined length and subjected to an annealing treatment as necessary.

  In addition, in a round bar material in which an aluminum alloy is continuously cast, a homogenization heat treatment at a temperature of 480 to 520 ° C. for 0.5 to 4 hours and / or a peeling process may be performed on the surface thereof.

  In this embodiment, when forging is performed, in warm forging, a lubricant is applied to the mold in order to prevent the material from seizing on the mold. In cold forging, it is not necessary to use a die lubricant.

  Further, when a lubricant is applied, it is preferable to previously form a lubricant film on the workpiece by immersing the material (workpiece) in a lubricant solution. In cold forging, it is preferable to perform a phosphoric acid film lubrication treatment.

  In this embodiment, when hot forging is performed, the temperature of the material is adjusted to 300 to 450 ° C., preferably 350 to 450 ° C. Furthermore, when performing warm forging, it is good to adjust raw material temperature to 380-460 degreeC, Preferably it is 400-450 degreeC. That is, when the material temperature is too low, molding cannot be performed or limit cracking occurs. Conversely, if the temperature is too high, swelling or the like may occur.

  In hot forging and warm forging, a lubricant is applied to the mold in order to prevent the material from sticking to the mold. As this coating method, for example, a method of spraying a lubricant directly on a forging die by spraying can be employed.

  In this embodiment, the load of the punch (3) of the forging device (1) can be adjusted to 10 to 400 tons (unit). Since the forging device (1) of the present invention has a specific structure as will be described later, it is possible to suppress the occurrence of a deteriorated recess due to wear on the pressure receiving plate (5). Therefore, it is possible to continuously operate with a high load as described above, and to improve workability. For reference, the forging device (1) of the present embodiment can be continuously operated at a speed of 10 to 50 spm.

  The cup-shaped product (W1) forged by the forging device (1) of the present embodiment is preferably subjected to a solution treatment and an aging treatment in order to impart strength and wear resistance. The solution treatment and the aging treatment refer to a treatment in which a heat treatment is performed at a predetermined temperature, followed by quenching, and again holding at a predetermined temperature for a predetermined time. The solution treatment temperature is preferably 490 to 500 ° C., and after quenching in water, it is maintained at 160 to 210 ° C. (preferably 170 to 190 ° C.) for 1 to 8 hours (preferably 3 to 6 hours). Age-hardened, and a forged product having a sufficient hardness of about 70 to 85 HRB (Rockwell B scale) can be obtained.

  As described above, according to the forging device (1) of the present embodiment, the punch support base (6) is formed on the lower surface (51) of the pressure receiving plate (5), and the punch support base (6). Since the punch support surface (61) that is in contact with the punch upper end surface (32) is formed to be smaller than the punch upper end surface (32), wear deterioration of the pressure receiving plate (5) is reduced as will be described below. Can be made.

  That is, when a large force acts in the contact direction between two metal members that are in contact with each other, stress concentrates on a member having a large opposing surface (contact surface) among the two members. More specifically, when a member having a large opposing surface (large member) and a member having a small opposing surface (small member) are brought into contact with each other and a large force acts in the contact direction, the small member on the opposing surface of the large member is exposed. Stress concentrates on the part corresponding to the periphery.

  Therefore, when the punch support surface (lower surface 51) of the pressure receiving plate (5) is larger than the punch upper end surface (32) as in the conventional forging apparatus shown in FIG. As described above, since a large amount acts on the member having the larger facing surface, that is, the pressure receiving plate (5) side, when this impact load is repeatedly applied, a deteriorated recess (9) due to wear is formed on the lower surface of the pressure receiving plate (51). . In particular, since this impact load is concentrated on a portion of the pressure receiving plate lower surface (51) corresponding to the outer peripheral edge of the punch upper end surface (32), the pressure receiving plate lower surface (51) has a punch upper end surface (32). A deteriorated recess (9) is formed such that the portion corresponding to the outer peripheral edge is deepest and becomes gradually shallower toward the inside. If such a deteriorated recess (9) is formed on the lower surface of the pressure receiving plate (punch support surface), the upper end surface (32) of the punch cannot be supported in a stable state, and the sitting of the punch (3) becomes worse. The punch (3) is wobbled or shaken, and the machining accuracy is lowered. Therefore, it is necessary to frequently replace the pressure receiving plate (5) in a short period of time, leading to a decrease in productivity and an increase in cost.

  Therefore, in the forging device (1) of this embodiment, as shown in FIG. 13, a punch support base (6) is formed on the lower surface (51) of the pressure receiving plate (5), and the punch support base (6) ) Is formed to be smaller than the punch upper end surface (32), the impact load when punching is applied to the punch upper end surface (32) outside the punch support surface (61). It acts to concentrate on the part corresponding to the periphery. For this reason, the deterioration recessed part (9) by wear comes to be formed in the upper end surface (32) of a punch (3), and reduces reliably that the deterioration recessed part by wear is formed in a pressure receiving plate (5). be able to. Therefore, the pressure receiving plate (5) can be used for a long period of time, the replacement frequency is reduced, and the productivity can be improved and the cost can be reduced.

  Here, in the present embodiment, although the wear deterioration of the pressure receiving plate (5) can be suppressed, the wear deterioration of the punch upper end surface (32) occurs. However, since the lower end surface (pressing surface 31) of the punch (3) is quickly worn out and deteriorated in this embodiment, the lower end surface (31) of the punch is worn out more than the deteriorated wear of the upper end surface (32) of the punch. Deterioration progresses quickly. For this reason, in this embodiment, the wear deterioration of the punch upper end surface (32) does not become a punch replacement factor, and the wear deterioration of the punch lower end surface (31) becomes a punch replacement factor. Therefore, the wear deterioration of the punch upper end surface (32) according to this embodiment does not cause a problem that the life of the punch (3) is reduced. As described above, in this embodiment, the wear deterioration of the pressure receiving plate (5) can be reduced as described above without causing an adverse effect due to the wear deterioration of the punch upper end surface (32). Can be reliably improved and the cost can be reduced.

  For reference, as shown in FIG. 13, the replacement span of the pressure receiving plate (5) when the wear deterioration of the lower surface of the pressure receiving plate (51) is small (in this embodiment) is as shown in FIG. Compared to the pressure plate replacement span when there is a lot of wear deterioration due to punch on the lower surface (conventional case), it can be 3 to 4 times longer than the replacement span, and the pressure plate (5) replacement frequency must be reliably reduced. Can do.

  In the present embodiment, it is necessary to set the size of the punch support surface (61) in the punch support base (6) to be equal to or less than the size of the upper end surface (32) of the punch (3). When the size of the support surface (61) is set smaller than the size of the punch upper end surface (32), that is, except that the size of the punch support surface (61) is equal to the size of the punch upper end surface (32), When the outer peripheral edge of the punch upper end surface (32) is disposed in a non-contact state with respect to the pressure receiving plate (5), it is possible to reliably suppress wear deterioration of the pressure receiving plate lower surface (51).

  Particularly in this embodiment, the inner diameter difference (radius difference) between the punch support surface (61) and the punch upper end surface (32) is set to 0.1 to 0.3 mm, preferably 0.15 to 0.25 mm. The outer peripheral edge of the punch support surface (61) is preferably positioned 0.1 to 0.3 mm inside, preferably 0.15 to 0.25 mm inner than the outer peripheral edge of the punch upper end surface (32). That is, when the difference between the inner diameters of both surfaces (61) and (32) is set within the specific range, it is possible to more reliably prevent the wear receiving plate (5) from being worn away. In other words, when the inner diameter difference between both surfaces (61) and (32) is too small, there is a possibility that the effect of suppressing the wear deterioration in the pressure receiving plate (5) cannot be exhibited sufficiently. On the other hand, when the inner diameter difference between both surfaces (61) and (32) is too large, the punch support surface (61), that is, the punch support base (6) becomes too small and the punch support base (6) is damaged. There is a fear.

  In the present invention, the chamfered portion (67) of the punch support base (6) is not included in the outer peripheral edge of the punch support surface (61), and is naturally not included in the punch support surface (61). Similarly, the chamfered portion (37) of the punch (3) is not included in the outer peripheral edge of the punch upper end surface (32), and is naturally not included in the punch upper end surface (32).

  In this embodiment, the area of the punch support surface (61) is 0.1 to 0.5% smaller than the area of the punch upper end surface (32), preferably 0.2 to 0.4% smaller. Is good. That is, when the area reduction rate is set within a specific range, it is possible to more reliably prevent wear deterioration of the pressure receiving plate (5). In other words, when the area reduction rate is too small, there is a possibility that the effect of suppressing wear deterioration in the pressure receiving plate (5) cannot be sufficiently exhibited. On the other hand, if the area reduction rate is too large, the punch support base (6) may be too small and be damaged.

  Furthermore, in this embodiment, the height (H) of the punch support base (6) is 0.1 to 1.5 mm, preferably 0.1 to 0.5 mm, more preferably 0.2 to 0.4 mm. It is good to set to. That is, when the height (H) of the support base is set within a specific range, the effect of suppressing wear deterioration of the pressure receiving plate (5) can be reliably obtained. In other words, when the height (H) of the support base is too low, there is a possibility that the effect of suppressing wear deterioration of the pressure receiving plate (5) cannot be obtained with certainty. On the other hand, if the height (H) of the support base is too high, the impact load concentrates on the punch support base (6) and the punch support base (6) may be damaged.

  Moreover, in this embodiment, since the pressure receiving plate (5) is formed in a truncated cone shape whose outer diameter gradually increases as it goes upward, the impact when punching is applied to the pressure receiving plate (5). The impact propagates upward while gradually spreading along the frustoconical pressure receiving plate (5). For this reason, the impact load can be evenly distributed over a wide range, and problems due to local concentration of the impact load, such as early wear of the pressure receiving plate (5), can be effectively prevented.

  Further, in the present embodiment, the inclination angle of the outer peripheral tapered surface (53) of the pressure receiving plate (5) with respect to the axis (C) is set to 20 to 70 °, preferably 30 to 60 °. That is, when the inclination angle is set within the specific range, the impact load can be efficiently dispersed in the outer diameter direction (horizontal direction), and local concentration of the impact load can be avoided. In other words, if the inclination angle of the pressure receiving plate outer peripheral tapered surface (53) is too small, the impact load may not be distributed over a wide range. On the contrary, when the inclination angle of the pressure receiving plate outer peripheral tapered surface (53) is too large, the pressure receiving plate (5) has a flat shape, and not only the impact load can be dispersed smoothly but also the load is concentrated in the center and the pressure receiving plate. (5) may be worn out and deteriorated early.

  In the present embodiment, the pressure receiving plate (5) includes a first divided body (501) constituted by the lower end portion including the punch support base (6) and a second divided body constituted by the remaining upper portion. (502) is formed by a long-term use, and the punch support base (6) has a deteriorated recess due to wear, and the pressure plate (5) needs to be replaced. Of the pressure receiving plate (5), only the first divided body (501) can be replaced, and the second divided body (502) can be used without replacement. Therefore, when parts are replaced due to wear deterioration, the number of replacement parts can be reduced, and the cost can be reduced.

  In the present embodiment, the case where the pressure receiving plate (5) is divided into two parts has been described as an example. However, the present invention is not limited thereto, and in the present invention, the pressure receiving plate is constituted by three or more divided bodies. Also good. In short, it is only necessary that one of the divided bodies is constituted by a portion including the punch support base in the pressure receiving plate.

  In the present embodiment, since the chamfered portion (67) is formed at the upper end of the outer peripheral surface of the punch support base (6), the impact load is concentrated on the outer peripheral portion of the punch support base (6). Therefore, it is possible to effectively prevent wear deterioration in the vicinity thereof.

  Furthermore, in this embodiment, since the chamfered portion (37) is also formed at the upper end of the outer peripheral surface of the punch (3), the impact load is concentrated on the outer peripheral portion of the upper end of the punch (3) as described above. It is possible to prevent the deterioration of wear around the area.

  Moreover, in this embodiment, while forming the recessed step part (57) which has an outer periphery parallel surface (573) parallel to an axis (C) in the outer periphery of the lower end part of a pressure receiving plate (5), punch holder (7 ) In the holding hole (75) is formed with a stepped portion (77) having an inner peripheral parallel surface (773) parallel to the axis (C), and the outer peripheral parallel surface (573) of the pressure receiving plate (5). The pressure receiving plate (5) is fitted to the punch holder (7) by fitting the convex stepped portion (77) to the concave stepped portion (57) while contacting the inner peripheral parallel surface (773) of the punch holder (7). Since the outer peripheral parallel surface (573) of the pressure receiving plate (5) is positioned on the inner peripheral parallel surface (773) of the punch holder (7), The centering of the side punch holder (7) can be performed reliably.

  Moreover, in the present embodiment, a retaining portion (56) having an outer peripheral surface parallel to the axis (C) is formed on the outer periphery of the upper end portion of the pressure receiving plate (5), while the punch holder (7) A concave step (756) having an inward inner peripheral surface parallel to the axis (C) is formed in the holding hole (75), and the retaining portion outer peripheral surface of the pressure receiving plate (5) is attached to the punch holder ( 7) Since the pressure receiving plate (5) is attached to the punch holder (7) while being in contact with the inner peripheral surface of the concave step portion of 7), the outer peripheral surface of the retaining portion of the pressure receiving plate (5) is the punch holder (7). The centering of the punch holder (7) on the upper side of the pressure receiving plate (5) can be reliably performed by restricting the position to the inner peripheral surface of the concave step portion.

  Thus, the centering with respect to the punch holder (7) can be accurately performed above and below the pressure receiving plate (5), the assembling accuracy of the pressure receiving plate (5) can be improved, and as a result, the processing accuracy and quality can be improved. Can be planned.

  In the present embodiment, the outer peripheral tapered surface (53) of the pressure receiving plate (5) is brought into contact with the inner peripheral tapered surface (73) of the punch holder (7), so that the pressure receiving plate (5) is brought into contact with the punch holder (7). It is also possible to perform centering, but in that case, the position is shifted to the contact position between the outer peripheral tapered surface (53) of the pressure receiving plate (5) and the inner peripheral tapered surface (73) of the punch holder (7). May occur, and the pressure receiving plate (5) may be disposed to be inclined with respect to the punch holder (7). When the pressure receiving plate (5) is mounted on the punch holder (7) with the pressure receiving plate (5) tilted, only a part of the pressure receiving plate (5) comes into contact with the upper end surface (32) of the punch. The load is concentrated only on a part of the pressure receiving plate (5), and the pressure receiving plate (5) may be deteriorated.

  Therefore, in the present embodiment, it is preferable that the outer peripheral tapered surface (53) of the pressure receiving plate (5) is not brought into contact with the inner peripheral tapered surface (73) of the punch holder (7). Specifically, between the outer peripheral taper surface (53) of the pressure receiving plate (5) and the inner peripheral taper surface (73) of the punch holder (7), 0.2 to 0.5 mm, preferably 0.3 to It is preferable to form a gap of 0.4 mm. That is, when this gap is too narrow, the outer peripheral tapered surface (53) of the pressure receiving plate (5) comes into contact with the inner peripheral tapered surface (73) of the punch holder (7) and tilts to the pressure receiving plate (5). May occur, and the above-mentioned problems may occur. On the other hand, when the gap is too wide, the upper mold (15) has a large number of cavities, and the strength of the upper mold (15) may not be sufficiently secured.

  Further, in the present embodiment, the outer periphery of the pressure receiving plate (5) with respect to the gap dimension between the outer peripheral tapered surface (53) of the pressure receiving plate (5) and the inner peripheral tapered surface (73) of the punch holder (7). The length in the axial direction of the parallel surface (573) (the length of the inner peripheral parallel surface 773 in the punch holder 7) is set to 20 times or more, preferably 25 times or more. That is, when the axial direction length of the outer peripheral parallel surface (573) is too short, a sufficient contact area with the inner peripheral parallel surface (773) of the punch holder (7) cannot be secured, and the pressure receiving plate (5) There is a possibility that the assembly accuracy with respect to the punch holder (7) is lowered. Specifically, the axial length of the outer peripheral parallel surface (573) is set to 2 to 6 mm, preferably 3 to 5 mm.

  In this embodiment, the gap dimension (clearance) between the outer peripheral parallel surface (573) of the pressure receiving plate (5) and the inner peripheral parallel surface (773) of the punch holder (7) is set to the punch support surface (61). It is preferable to set smaller than the difference between the radial dimension of the punch and the radial dimension of the punch rear end face (32). That is, in this case, the pressure receiving plate (5) can be accurately aligned with the punch (3), and the punch support surface (61) can be reliably brought into contact with the inside of the punch rear end surface (32). Thus, the effect of suppressing the wear of the pressure receiving plate (5) can be obtained more reliably. Specifically, the gap between the outer peripheral parallel surface (573) and the inner peripheral parallel surface (773) is set to 0.05 to 0.2 mm, preferably 0.1 to 0.15 mm.

  In this embodiment, since the punch (3) is assembled to the punch holder (7) via the punch case (4), the punch (3) is restrained by the punch case (4). The punch (3) can be prevented from swinging and the processing accuracy and product quality can be further improved. Further, when the punch is driven, the gap between the punch (3) and the inner peripheral surface of the die hole is sealed by the punch case (4) so that hermetic forging can be performed, and the lower end surface (41) of the punch case (4) The height of the peripheral wall of the forged product (W1) can be accurately controlled, and the processing accuracy and product quality can be further improved.

  Furthermore, in this embodiment, since the punch (3) and the punch case (4) are formed separately, compared with the case where these are integrally formed, each member (3) (4) has a mold. The stress can be dispersed, the wear resistance can be improved, and the life can be prolonged.

  In the above embodiment, the pressure receiving plate (5) has a truncated cone shape. However, the pressure receiving plate (5) is not limited to this, and in the present invention, as shown in FIG. It is also possible to use a cylindrical pressure receiving plate (5) parallel to C).

  Moreover, in the said embodiment, although the outer periphery parallel surface (573) is formed in the lower end part of a pressure receiving plate (5), the formation position of an outer periphery parallel surface (573) is specifically limited in this invention. For example, the outer peripheral parallel surface (573) may be formed at an intermediate portion or an upper portion of the outer peripheral tapered surface (53) of the pressure receiving plate (5).

  Further, in the above embodiment, the outer peripheral parallel surface (573) of the pressure receiving plate (5) is formed by one surface (vertical surface) of the recessed step portion (57) recessed inwardly of the outer peripheral tapered surface (53). However, the present invention is not limited to this, and in the present invention, a part of the outer peripheral portion of the pressure receiving plate (5) protrudes outward from the outer peripheral tapered surface (53), and one surface (vertical surface) of the protruding portion. Thus, an outer peripheral parallel surface may be formed.

  In the above embodiment, the punch (3) is held by the punch holder (7) via the punch case (4). However, the present invention is not limited to this. In the present invention, without using the punch case, The punch case can be omitted by holding the punch on the punch holder.

  Moreover, in the said embodiment, although the upper end part of the punch (3) uses the cylindrical shape, it is not restricted only to it, In this invention, the upper end part shape of a punch becomes large diameter as it goes upwards. A frustoconical shape can also be used. In this case, since the propagation direction of the impact at the time of punching is the inclination direction (extension direction) of the outer peripheral tapered surface in the truncated cone portion of the punch, the punch support base portion ( It is preferable to set the horizontal distance between 6) and the outer surface extension line of the punch truncated cone part within 5 mm.

<Example 1>
A die set was produced based on the die set of the forging device (see FIGS. 2 to 4) of the above embodiment. That is, a die (2) having a diameter of the die hole (25) of 34 mm was prepared. A punch (3) having a diameter of the processed portion (lower end) of 29 mm and an upper end surface (32) on the pressure receiving plate side of 34 mm was prepared. The material of the punch (3) is carbon steel.

  As the pressure receiving plate (5), a substantially truncated cone shape having a smaller diameter toward the lower side and capable of being divided into two parts in the vertical direction was prepared. In the pressure receiving plate (5), a concave step portion (57) having a surface parallel to the axial direction (outer peripheral parallel surface 573) and a surface orthogonal to the axial direction (orthogonal surface 571) on the outer periphery of the lower end portion. Formed. The length in the axial direction of the outer peripheral parallel surface (573) in the concave step portion (57) was set to 5 mm, and the length in the radial direction (horizontal direction) of the orthogonal surface (571) was set to 48 mm. The lower surface (51) of the pressure receiving plate (5) has a diameter of 48 mm, and the outer peripheral tapered surface (53) is adjusted to have an inclination angle of 55 ° with respect to the axis (C). Further, a punch support base (6) having a diameter of 33.4 mm and a height of 0.2 mm is formed on the lower surface (51) of the pressure receiving plate (5), and the punch support surface of the punch support base (6) is formed. The diameter of (61) was set to 33 mm. The material of the pressure receiving plate (5) is the same as that of the punch.

  As the punch holder (7), a punch case (4) and a pressure receiving plate (5) having holding holes (75) corresponding to the outer peripheral shape were prepared.

  Other configurations are the same as in the above embodiment, and the die set is assembled. Then, the positioning accuracy (centering accuracy) of the pressure receiving plate (5) in this die set was inspected. In the inspection method, the amount of displacement from the center position of the reference in the assembled pressure receiving plate (5) is measured, and when the amount of displacement is less than 0.15 mm, “◎”, 0.15-0.3 mm. The thing was determined as “◯”. The inspection results are shown in Table 1.

  Also, this die set is mounted on the same forging device (1) as in the above embodiment, the press load is set to 90 tons using the device (1), and the speed is 40 spm as in the above embodiment. Then, a forging process was performed on the aluminum alloy workpiece (W) to produce a cup-shaped forged product. And when this forging process reached 20000 times, the abrasion state in the lower surface (51) of a pressure receiving plate (5) was observed visually, and the abrasion state was confirmed. The results are shown in Table 1.

<Example 2>
As the pressure receiving plate (5), a plate in which the recessed step portion (57) was not formed on the outer periphery of the lower end portion was prepared, and the centering inspection and the wear confirmation were performed in the same manner as above except that.

<Comparative example>
As the pressure receiving plate (5), a punch support base (6) is not formed and the entire surface has a flat bottom surface (51), and a concave step (57) is not formed on the outer periphery of the lower end. Except for the above, centering inspection and wear confirmation were performed in the same manner as above.

<Evaluation>
As shown in Table 1, in the die sets of Examples 1 and 2, no deterioration recess due to wear was confirmed on the lower surface of the pressure receiving plate. On the other hand, in the die set of the comparative example, a deteriorated recess due to wear was confirmed on the lower surface of the pressure receiving plate. The deteriorated recess was deeper in the portion corresponding to the outer peripheral edge of the punch upper end surface, and was gradually formed shallower toward the inside.

  Therefore, in the embodiment related to the present invention, the replacement span of the pressure receiving plate can be lengthened and the replacement frequency can be reduced as compared with the comparative example that departs from the gist of the present invention.

  In addition, the die set of Example 1 had very high centering accuracy of the pressure receiving plate as compared with Examples 2 and Comparative Examples.

  In the die sets of Examples 1 and 2, a deteriorated recess due to wear was confirmed on the upper end surface of the punch along the outer peripheral edge. However, the wear deterioration of the upper end surface of the punch was very small compared to the wear deterioration of the lower end surface (pressed surface) of the punch.

  The press working apparatus of the present invention can be suitably used for forging.

1 ... Forging device 15 ... Upper die (movable side die)
2 ... Die 3 ... Punch 32 ... Upper end surface (base end surface)
37 ... Chamfer 4 ... Punch case 42 ... Upper end surface (base end surface)
5 ... Pressure receiving plates 501, 502 ... Divided body 51 ... Lower surface (pressure receiving surface)
53 ... Tapered outer surface (outer peripheral surface)
57 ... Concave step 573 ... Outer peripheral parallel surface 6 ... Punch support base 61 ... Punch support surface 67 ... Chamfer 7 ... Punch holder 73 ... Inner taper surface (inner peripheral surface)
75 ... Holding hole 77 ... Convex step 773 ... Parallel surface W ... Work

Claims (10)

In a state where the base end side of the punch is supported by the pressure receiving surface of the pressure receiving plate, the press working device presses the tip of the punch against the workpiece,
On the pressure receiving surface of the pressure receiving plate, the punch support base is formed so as to protrude, and the punch support base is provided with a punch support surface in contact with the base end surface of the punch,
While the pressure receiving plate is divided into a plurality of parts, one of the plurality of divided bodies is constituted by a portion including the punch support base part of the pressure receiving plate,
A cylindrical punch case that accommodates the punch along the axial direction, and a punch holder that holds the punch case and the pressure receiving plate,
The base end surface of the punch is disposed closer to the punch tip side than the base end surface of the punch case, and the base end surface of the punch case is disposed in contact with the outside of the punch support base on the pressure receiving surface of the pressure receiving plate. Press processing equipment. The lower surface of the pressure receiving plate constitutes the pressure receiving surface,
2. The press working apparatus according to claim 1, wherein the pressure receiving plate includes a first divided body constituting a lower end portion of the pressure receiving plate and a second divided body constituting an upper portion excluding the lower end portion of the pressure receiving plate.   The press working apparatus according to claim 1, wherein a chamfered portion is formed outside the punch support surface of the punch support base portion.   The press working apparatus according to any one of claims 1 to 3, wherein a chamfered portion is formed between a base end surface and an outer peripheral surface of the punch. The press working apparatus according to any one of claims 1 to 4 , wherein a size of the punch support surface is set to be equal to or less than a size of a base end surface of the punch. The press working apparatus of any one of Claims 1-5 by which the outer periphery of a punch base end surface is arrange | positioned in a non-contact state with respect to a pressure receiving plate. The press working apparatus according to any one of claims 1 to 6 , wherein the outer peripheral edge of the punch support surface is disposed 0.1 to 0.3 mm inside the outer peripheral edge of the punch base end surface. The press working apparatus according to any one of claims 1 to 7 , wherein an area of the punch support surface is formed to be 0.1 to 0.5% smaller than an area of the punch base end face. The press working apparatus according to any one of claims 1 to 8 , wherein a height of the punch support base is set to 0.1 to 1.5 mm. Using a press working apparatus according to any one of claims 1 to 9, the workpiece by pressing, press-forming method, which comprises producing a molded article.

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