JP2007275905A - Upsetting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an upsetting method by which working can effectively be performed and forming pressure can be reduced. <P>SOLUTION: A bar-like blank 1 is set in an inserting hole 12 of a guide 11, and the one end part 1a of the blank 1 projected from a blank outlet part 12a of a guide 11 is set so as to face an inlet part 22a of a forming cavity 22 in a die 20 (a setting step). After the setting step, the blank 1 is pressurized axially to thereby push the material of the blank 1 pushed out from the blank outlet part 13 of the guide 11, into the forming cavity 22 from the inlet part 22a, and thus a small-diameter part is formed (a small diameter part forming step). Further, after setting step, while pressurizing the blank 1 axially, the guide 11 is shifted in a direction G reverse to the pressurizing direction P of the blank 1, thereby the exposed part 2 of the blank 1 exposed at the interval between the receiving face 21 of the die 20 and the distal end face 13 of the guide 11 is diametrically enlarged between the receiving face 21 and the distal end face 13 of the guide 11, and a diametrically enlarged part is thus formed (a large diameter part forming step). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an upsetting method and an upsetting apparatus for forming a small diameter portion and a large diameter portion at one end portion in the axial direction of a rod-shaped material and a portion on the other end side from the one end portion, respectively.

  Conventionally, a product in which a small diameter portion and a large diameter portion are formed at one end portion and the other end portion in the axial direction has been manufactured by the following method, for example.

  First, one end portion of the rod-shaped material in the axial direction is subjected to diameter reduction processing by a diameter reduction processing apparatus. Next, this material is conveyed to a diameter expansion processing apparatus installed separately from the diameter reduction processing apparatus. And the product of the shape mentioned above was manufactured by carrying out the diameter expansion process of the other end part of the axial direction of a raw material with this diameter expansion processing apparatus.

  Moreover, although it is not the method of manufacturing the product of the shape mentioned above, the following method is known as a conventional upsetting method (for example, refer patent document 1-3).

That is, a rod-shaped material is inserted and disposed in an insertion hole provided in the guide, and the material is held in a buckling-prevented state. In addition, the tip of the guide is disposed in the molding concave portion of the mold, and the protruding portion of the material protruding from the material outlet portion of the tip surface of the guide is received by the bottom surface of the molding concave portion of the mold. Next, while pressing the material in the axial direction, the exposed portion of the material exposed between the bottom surface of the molding recess and the tip surface of the guide is moved by moving the guide in the direction opposite to the pressing direction of the material. The diameter is expanded inside and a large diameter portion is formed in the material. According to this method, there is an advantage that the material can be prevented from buckling when the large diameter portion is formed.
JP-A-48-62646 (Claim 1, FIGS. 1 to 4) JP 2005-144554 A Japanese Patent Laying-Open No. 2005-59097 (Claim 10, FIGS. 6 to 13)

  Thus, in the former method, since the material has to be transported from the diameter reducing apparatus to the diameter expanding apparatus, workability is poor. Moreover, in order to prevent a raw material from buckling at the time of formation of a large diameter part, it is necessary to use a raw material with a large diameter. For this reason, high molding pressure is required, and the service life of the mold is reduced.

  In the latter method, a small diameter portion having a diameter smaller than that of the material could not be formed in the material, and a product having a small difference between the diameter of the small diameter portion and the diameter of the large diameter portion could be manufactured. There wasn't. For this reason, the shape of products that can be manufactured is limited.

  The present invention has been made in view of the above-described technical background, and an object thereof is an upsetting method capable of efficiently performing processing and reducing a molding pressure, and upsetting used in the upsetting method. It is to provide a processing apparatus.

  The present invention provides the following means.

[1] An upsetting method for forming a small-diameter portion and a large-diameter portion at one end portion in the axial direction of a material and a portion on the other end side from the one end portion,
A rod-shaped material whose diameter is set between the diameter of the small diameter part and the diameter of the large diameter part,
A guide having an insertion hole for inserting and holding the material in a buckling-preventing state, and a material outlet portion formed of one end opening of the insertion hole on the distal end surface;
Using a mold having a molding cavity for forming a small diameter portion and a receiving surface, and a receiving surface provided with an inlet portion of the molding cavity,
An arrangement step of arranging the material in the insertion hole of the guide and arranging one end portion of the material protruding from the material outlet portion of the guide facing the inlet portion of the molding cavity of the mold,
After the placing step, by pressing the material in the axial direction, the material of the material extruded from the material outlet portion of the guide is pushed into the molding cavity from the inlet portion, and a small diameter portion forming step for forming a small diameter portion,
The material exposed between the receiving surface of the mold and the tip surface of the guide by moving the guide in a direction opposite to the pressing direction of the material while pressing the material in the axial direction after the arranging step. A large-diameter portion forming step of expanding the diameter of the exposed portion between the receiving surface and the tip end surface of the guide and forming a large-diameter portion;
The upsetting method characterized by including.

[2] The mold has a molding recess for forming a large diameter portion, and the bottom surface of the molding recess is formed by a receiving surface of the mold.
At the tip portion of the guide, a molding convex portion corresponding to the molding concave portion of the mold is formed, and the tip surface of the molding convex portion is formed by the tip surface of the guide,
In the large-diameter portion forming step, the exposed portion of the material is expanded between the receiving surface of the mold and the tip end surface of the guide, so that the material of the exposed portion of the material is filled into the molding recess, and the large-diameter portion The upsetting method as recited in the aforementioned Item 1, wherein.

  [3] In the large-diameter portion forming step, the material of the exposed portion of the material is filled in the molding recess so that an unfilled portion not filled with the material remains in the corner, and then the molding recess 3. The upsetting method according to item 2 above, wherein the large-diameter portion is formed by pressurizing the material in the molding recess with the tip surface of the guide so that the unfilled portion is filled with the material.

[4] A large-diameter-portion forming concave portion is provided at the distal end portion of the guide, and the bottom surface of the molded concave portion is formed by the distal end surface of the guide,
The mold has a molding convex part corresponding to the molding concave part of the guide, and the tip surface of the molding convex part is formed by the receiving surface of the mold,
In the large-diameter portion forming step, the exposed portion of the material is expanded between the receiving surface of the mold and the tip end surface of the guide, so that the material of the exposed portion of the material is filled into the molding recess, and the large-diameter portion The upsetting method as recited in the aforementioned Item 1, wherein.

  [5] In the large-diameter portion forming step, the material of the exposed portion of the raw material is filled in the molding recess so that an unfilled portion not filled with the material remains in the corner, and then the molding recess 5. The upsetting method according to item 4, wherein the large-diameter portion is formed by pressurizing the material in the molding concave portion with the tip surface of the guide so that the unfilled portion is filled with the material.

  [6] The upsetting method according to any one of items 1 to 5, wherein the large-diameter portion forming step is performed after the small-diameter portion forming step.

  [7] The upsetting method according to any one of items 1 to 5, wherein the small diameter portion forming step and the large diameter portion forming step are simultaneously performed.

  [8] An upsetting product manufactured by the upsetting method according to any one of 1 to 7 above.

[9] An upsetting apparatus for forming a small-diameter portion and a large-diameter portion at one end portion in the axial direction of the rod-shaped material and a portion on the other end side from the one end portion,
A guide having a through hole for inserting and holding the rod-shaped material in a buckling-prevented state, and a guide provided with a material outlet portion consisting of one end opening of the insertion hole on the tip surface;
A mold cavity having a small-diameter portion forming cavity for forming a small-diameter portion by reducing the cross-sectional area of one end portion of the material, and a receiving surface, and a mold provided with an inlet portion of the molding cavity on the receiving surface;
A material pressurizing means for pressurizing the material disposed in the insertion hole of the guide in the axial direction;
Guide driving means for moving the guide in a direction opposite to the pressing direction of the material,
With
The molding cavity of the mold forms a small diameter part by pushing the material of the material pushed out from the material outlet part of the guide by the material pressurizing means into the molding cavity from the inlet part,
The exposed portion of the material exposed between the mold receiving surface and the guide tip surface is expanded between the mold receiving surface and the guide tip surface to form a large diameter portion. An upsetting apparatus characterized by

[10] The mold has a molding recess for forming a large diameter portion, and the bottom surface of the molding recess is formed by a receiving surface of the mold.
10. The upsetting apparatus according to the above item 9, wherein the tip of the guide is formed with a molding convex portion corresponding to the molding concave portion of the mold, and the tip surface of the molding convex portion is formed by the tip surface of the guide.

[11] The tip of the guide is provided with a molding recess for forming a large diameter portion, and the bottom of the molding recess is formed by the tip of the guide,
10. The upsetting apparatus according to claim 9, wherein the mold has a molding convex portion corresponding to the molding concave portion of the guide, and a tip surface of the molding convex portion is formed by a receiving surface of the mold.

  The present invention has the following effects.

  In the invention of [1], the small diameter portion forming step and the large diameter portion forming step can be performed by, for example, one upsetting apparatus. Therefore, it can process efficiently.

  Furthermore, in the large diameter portion forming step, since the material is disposed in a buckling prevention state in the insertion hole of the guide, the material is prevented from buckling when the large diameter portion is formed. Therefore, a material having a comparatively small diameter can be used, so that the molding pressure can be reduced and the useful life of the mold can be extended.

  In the invention of [2], in the large-diameter portion forming step, since the large-diameter portion is formed by filling the material of the exposed portion of the material into the molding concave portion, the large-diameter portion can be precisely formed into a predetermined shape. Yes.

  In the invention of [3], the molding pressure during the formation of the large diameter portion can be reduced. In addition, by filling the material in the unfilled portion in the molding recess, an upset product without a lack of thickness can be manufactured.

  The inventions [4] and [5] have the same effects as the inventions [2] and [3], respectively.

  In the invention of [6], the small diameter portion forming step and the large diameter portion forming step can be reliably performed.

  In the invention of [7], since the small diameter portion forming step and the large diameter portion forming step are simultaneously performed, the processing can be performed extremely efficiently.

  In the invention of [8], it is possible to provide an upsetting product in which a small-diameter portion and a large-diameter portion are respectively formed at one end portion in the axial direction and a portion on the other end side from the one end portion.

  In the invention of [9], an upsetting apparatus that can be suitably used in the upsetting method according to the present invention can be provided.

  In the inventions [10] and [11], the large diameter portion can be precisely formed in a predetermined shape.

  Next, several embodiments of the present invention will be described below with reference to the drawings.

  FIGS. 1-7 is a figure explaining the upsetting method and the upsetting apparatus which concern on 1st Embodiment of this invention.

  In FIG. 1, (10A) is an upsetting apparatus according to the first embodiment of the present invention, and (1) is a material.

  In FIG. 7, (5A) is an upsetting product manufactured using the upsetting apparatus (10A) of the first embodiment. A small-diameter portion (6) is formed at one end portion in the axial direction of the upsetting product (5A). In addition, a large-diameter portion (7) having a diameter larger than that of the small-diameter portion (6) is formed at the other end portion as a portion on the other end side from the one end portion in the axial direction of the upsetting processed product (5A). ing. The cross-sectional shapes of the small diameter part (6) and the large diameter part (7) of the upsetting product (5A) are circular. The large-diameter portion (7) is formed to bulge out in a substantially disc shape outward in the radial direction around the shaft portion of the upsetting product (5A).

  This upsetting product (5A) is used, for example, in automobile parts, and more specifically, it is used as a preform for manufacturing pulleys and gears in which a shaft and a flange are integrally formed. is there. However, in the present invention, the upsetting product (5A) is not limited to the one described above.

  The material (1) is in the form of a rod as shown in FIG. 1, and more specifically, it is a straight solid round bar. The material (1) is made of a metal material. More specifically, the material (1) is made of aluminum or an aluminum alloy. The cross-sectional shape of the material (1) is circular, and the diameter of the material (1) is set constant in the axial direction.

  In the present invention, the material of the material (1) is not limited to aluminum or an aluminum alloy, but may be, for example, brass, copper (including the alloy), iron, or steel. . In the present invention, the cross-sectional shape of the material (1) is not limited to a circular shape, and may be a polygonal shape such as a square shape or a hexagonal shape. In addition, the material (1) may be made of, for example, an extruded material, or may be made of a rolled material such as a continuous cast rolled material manufactured by a Properti method, or by other methods. It may be manufactured.

  A small diameter portion (6) smaller than the diameter of the material (1) is formed at one end portion (1a) in the axial direction of the material (1), and the one end portion (1a) in the axial direction of the material (1). In addition, a large diameter portion (7) larger than the diameter of the material (1) is formed at the other end portion (1b) as the other end portion.

  The length of the material (1) is, for example, in the range of 200 to 600 mm. The diameter of the material (1) is set between the diameter of the small diameter part (6) and the diameter of the large diameter part (7) of the upsetting product (5A). Within range.

  The length of the upsetting product (5A) is, for example, in the range of 100 to 500 mm. The minimum diameter of the small diameter portion (6) of the upsetting product (5A) is, for example, in the range of 10 to 20 mm. The maximum diameter of the large diameter portion (7) of the upsetting product (5A) is, for example, in the range of 50 to 200 mm.

  However, in this invention, the dimension of a raw material (1) and the dimension of each site | part of an upsetting product (5A) are not limited to being in said range. For example, the size of the material (1) and the size of each part of the upsetting product (5A) can be set so that the object of the present invention can be achieved in accordance with the production of a desired product.

  The upsetting apparatus (10A) of the first embodiment includes one end (1a) in the axial direction of the material (1) and the other end (1b) as a part on the other end side from the one end (1a). And a small-diameter portion (6) and a large-diameter portion (7), respectively.

  This upsetting apparatus (10A) includes a guide (11), a mold (20), a material pressurizing means (30), a guide driving means (35), and a knockout punch (40). .

  The guide (11) has an insertion hole (12) for inserting and holding the material (1) in a buckling-prevented state and slidably movable in the axial direction. The insertion hole (12) is provided so as to penetrate in the axial direction from the center of the rear end surface of the guide (11) toward the center of the front end surface (13) of the guide (11). Therefore, a material outlet portion (12a) including an opening at one end of the insertion hole (12) is formed at the center portion of the distal end surface (13) of the guide (11).

  The guide (11) is formed by inserting a material (1) (material of the material (1)) inserted into the insertion hole (12) into a molding cavity (22) for forming a small diameter portion of a mold (20) described later. And it guides in the shaping | molding recessed part (23) for large diameter part formation.

  The cross-sectional shape of the insertion hole (12) of the guide (11) is a shape corresponding to the cross-sectional shape of the material (1), that is, a circular shape. The diameter of the insertion hole (12) is set to be the same as or slightly smaller than the diameter of the material (1), so that the material (1) is prevented from buckling in the insertion hole (12). The insertion hole (12) is configured to be inserted and arranged so as to be slidable in the axial direction.

  The mold (20) has a receiving surface (21) and a small-diameter portion forming molding cavity (22).

  The molding cavity (22) is for forming the small diameter portion (6) by reducing the cross-sectional area of the one end portion (1a) of the material (1).

  The receiving surface (21) receives the material of the material (1). Around the receiving surface (21), a cylindrical (in detail, cylindrical) peripheral wall portion (24) is provided so as to protrude from the receiving surface (21) so as to surround the receiving surface (21). It has been. As a result, a large-diameter-portion forming concave portion (23) having the receiving surface (21) as a bottom surface is formed at the end of the mold (20). Therefore, the bottom surface of the molding recess (23) is formed by the receiving surface (21), that is, the receiving surface (21).

  In addition, an inlet portion (22a) of the molding cavity (22) is provided at the central portion of the receiving surface (21), and a molding cavity (22) extends from the inlet portion (22a) in the axial direction of the mold (20). 22) is formed inside the mold (20). The diameter of the entrance (22a) is set corresponding to the diameter of the material (1), for example.

  A molding convex part (14) corresponding to the molding concave part (23) of the mold (20) is formed at the tip part including the tip surface (13) of the guide (11). The front end surface of the molding convex portion (14) is formed by the front end surface (13) of the guide (11), that is, the front end surface (13) of the guide (11). This shaping | molding convex part (14) is comprised so that it may fit in a fitting state in the shaping | molding recessed part (23) of a metal mold | die (20).

  The material pressurizing means (30) pressurizes the material (1) inserted and disposed in the insertion hole (12) of the guide (11) in the axial direction. The material pressing means (30) has a punch (31) and a punch drive source (32) for driving the punch (31). Then, the punch (31) is moved by the driving force of the punch driving source (32) to press the material (1) in the axial direction from the other end (1b) with the punch (31). . As the punch drive source (32), for example, a fluid pressure cylinder (such as a hydraulic cylinder or a gas pressure cylinder) is used.

  The guide driving means (35) moves the guide (11) in a direction opposite to the pressing direction of the material (1) by the material pressing means (30), and is connected to the guide (11). As a drive source of the guide drive means (35), for example, a fluid pressure cylinder (such as a hydraulic cylinder or a gas pressure cylinder) is used.

  The knockout punch (40) is for extruding the upsetting product (5A) from the molding cavity (22) and the molding recess (23) of the mold (20) after the upsetting process. This knockout punch (40) is disposed at the bottom of the molding cavity (22) of the mold (20). As the drive source (41) of the knockout punch (40), for example, a fluid pressure cylinder (such as a hydraulic cylinder or a gas pressure cylinder) is used.

  Next, an upsetting method using the upsetting apparatus (10A) of the first embodiment will be described below.

  First, as shown in FIG. 1, the molding convex part (14) at the tip of the guide (11) is fitted into the molding concave part (23) of the mold (20) in an adapted state. In this fitted state, the receiving surface (21) of the mold (20) (that is, the bottom surface of the molding recess (23)) and the tip surface (13) of the guide (11) (that is, the tip of the molding projection (14)). There is no gap between them.

  Further, the material (1) is inserted and arranged in the insertion hole (12) of the guide (11), and one end (1a) of the material (1) protruding from the material outlet (12a) of the guide (11) It arrange | positions facing the entrance part (22a) of the shaping | molding cavity (22) of a metal mold | die (20). In the present embodiment, one end portion (1a) of the material (1) is disposed in the inlet portion (22a) of the molding cavity (22) [arrangement step]. In addition, a raw material (1) is heated beforehand as needed.

  Next, in this state, as shown in FIG. 2, the material (1) is pressed in the axial direction from the other end (1b) by the punch (31) of the material pressing means (30) (the pressing direction (P )), The material of the material (1) pushed out from the material outlet part (12a) of the guide (11) (specifically, the material of one end part (1a) of the material (1)) is introduced from the inlet part (22a). Push into molding cavity (22). Thereby, the small diameter part (6) smaller than the diameter of a raw material (1) is formed in the one end part (1a) of a raw material (1) [small diameter part formation process].

  In the small diameter portion forming step, the material of the material (1) is pushed into the molding cavity (22) from the inlet portion (22a) while the cross-sectional area of the one end (1a) of the material (1) is reduced. In addition, the formation method of this small diameter part (6) enters the category of the forward extrusion method.

  When the material of the raw material (1) is filled in the molding cavity (22) and the small diameter portion (6) is formed at one end (1a) of the raw material (1) (that is, after the small diameter portion forming step). As shown in FIG. 3, the guide (11) is moved in the direction (G) opposite to the pressing direction (P) of the material (1) while the material (1) is continuously pressed in the axial direction by the punch (31). Move. Thereby, as shown in FIG.3 and FIG.4, the exposed part (2) of the raw material (1) exposed between the receiving surface (21) of a metal mold | die (20) and the front end surface (13) of a guide (11). ) Between the receiving surface (21) of the mold (20) and the tip surface (13) of the guide (11), that is, in the molding recess (23), thereby exposing the material (1). The material of the part (3) is filled into the molding recess (23). The moving speed of the guide (11) is set lower than the moving speed of the punch (31), that is, the pressurizing speed of the material (1).

  In this step, the guide (11) is moved in the direction (G) opposite to the pressing direction (P) of the material (1) while pressing the material (1) in the axial direction. The material of the exposed portion (2) is sequentially filled into the molding recess (23). Moreover, the unfilled part (N) which is not filled with the material of the exposed part (2) of a raw material (1) remains in the corner part in a shaping | molding recessed part (23).

  And as shown in FIG. 4, the material of the exposed part (2) of a raw material (1) remains in the shaping | molding recessed part (23), and the unfilled part (N) which is not filled with the material in the corner remains a little. When the state is filled, the movement of the guide (11) is stopped.

  Thereafter, as shown in FIG. 5, the guide (11) is moved in the same direction and at the same speed as the movement direction of the punch (31) (that is, the pressing direction (P) of the material (1)). 31) and the tip surface (13) of the guide (11) (that is, the tip surface of the molding convex portion (14)) pressurize the material in the molding concave portion (23) together. As a result, the material in the molding recess (23) is filled in the unfilled portion (N) in the molding recess (23), and the material in the molding recess (23) is completely removed by eliminating the unfilled portion (N). To charge. Thereby, the large diameter part (7) larger than the diameter of a raw material (1) is formed in the other end part (1b) of a raw material (1) [large diameter part formation process].

  Here, pressurization of the material in the molding recess (23) by the tip surface (13) of the guide (11) is performed by reversely driving the drive source of the guide drive means (35).

  Next, as shown in FIG. 6, the guide (11) is separated from the mold (20), and then the upset product (5A) is formed by the knockout punch (40) into the molding recess (23) of the mold (20) and By pushing out from the molding cavity (22), the upsetting product (5A) shown in FIG. 7 is obtained.

  In the upsetting product (5A) thus obtained, various processes such as a process for forming a final shape of a desired product and a deburring process are performed after the upsetting process.

  Thus, the upsetting method of the first embodiment has the following advantages.

  In this upsetting method, the small-diameter portion forming step and the large-diameter portion forming step can be performed by one upsetting apparatus (10A), so that the processing can be performed efficiently.

  Furthermore, in the large diameter portion forming step, since the material (1) is disposed in a buckling-prevented state in the insertion hole (12) of the guide (11), the material (1) is formed when the large diameter portion (7) is formed. ) Is prevented from buckling. Therefore, it is possible to use a material (1) having a relatively small diameter, thereby reducing the molding pressure and extending the service life of the mold (20). Further, since the molding pressure can be reduced, the material (1) enters the gap (clearance) between the insertion hole (12) of the guide (11) and the punch (31). The trouble that the punch (31) cannot move in the insertion hole (12) can be prevented.

  Furthermore, in the large diameter portion forming step, the large diameter portion (7) is formed by filling the material of the exposed portion (2) of the material (1) into the molding concave portion (23). ) Can be precisely formed in a predetermined shape.

  Further, in the large-diameter portion forming step, the material of the exposed portion (2) of the raw material (1) remains in the molding recess (23), and an unfilled portion (N) not filled with the material remains in the corner portion. Then, the material in the molding recess (23) is filled with the material by pressurizing the material in the molding recess (23) with the tip surface (13) of the guide (11). The molding pressure during the formation of the large diameter portion (7) can be reduced. Therefore, the service life of the mold (20) can be further extended. Further, by filling the unfilled portion (N) in the molding recess (23) with a material, an upsetting product (5A) having no lacking wall can be manufactured.

  Moreover, in this upsetting method, the small diameter part (6) smaller in diameter than the raw material (1) can be formed in the raw material (1), and the diameter and the large diameter part (7) of the small diameter part (6) can be formed. ) Product with a small difference from the diameter (upsetting product (5A)) can be manufactured. Therefore, the shape of a product that can be manufactured can be increased, and thus a product having a more complicated shape (upsetting product (5A)) can be manufactured.

  Moreover, since the large diameter portion forming step is performed after the small diameter portion forming step, the small diameter portion forming step and the large diameter portion forming step can be performed reliably.

  In the first embodiment, the large diameter portion forming step is performed after the small diameter portion forming step. However, in the present invention, in addition, the small diameter portion forming step and the large diameter portion forming step are simultaneously performed. Also good. By doing so, processing can be performed extremely efficiently.

  8-15 is a figure explaining the upsetting method and the upsetting apparatus which concern on 2nd Embodiment of this invention. In these drawings, the same elements as those of the upsetting apparatus (10A) of the first embodiment are denoted by the same reference numerals.

  In FIG. 8, (10B) is the upsetting apparatus of the second embodiment.

  In FIG. 15, (5B) is an upsetting product manufactured by using the upsetting apparatus (10B) of the second embodiment. This upset product (5B) is formed with a small diameter portion (6) at one end in the axial direction and the one end in the axial direction, like the upset product (5B) of the first embodiment. A large-diameter portion (7) is formed at the other end portion as the portion on the other end side.

  The configuration of the upsetting apparatus (10B) of the second embodiment will be described below with a focus on the configuration different from the upsetting apparatus (10A) of the first embodiment.

  In the upsetting apparatus (10B) of the second embodiment, the guide (11) has a cylindrical shape (in detail, a cylindrical shape) around the tip surface (13) so as to surround the tip surface (13). The peripheral wall portion (16) of the guide (11) protrudes from the distal end surface (13). As a result, a large-diameter-portion forming recess (15) with the tip surface (13) of the guide (11) as the bottom surface is formed at the tip of the guide (11). Therefore, the bottom surface of the molding recess (15) is formed by the tip surface (13) of the guide (11), that is, the tip surface (13) of the guide (11). Moreover, the material exit part (12a) which consists of one end opening part of the insertion hole (12) is provided in the center part of the front end surface (13) of this guide (11).

  The mold (20) has a molding convex part (26) corresponding to the molding concave part (15) of the guide (11). That is, the peripheral wall portion (16) of the molding recess (15) of the guide (11) is fitted around the receiving surface (21) of the mold (20) so as to surround the receiving surface (21). An annular groove (25 in detail) is provided. Thereby, the shaping | molding convex part (26) which uses the receiving surface (21) of a metal mold | die (20) as a front end surface is formed in the edge part of a metal mold | die (20). Therefore, the front end surface of the molding convex portion (26) is formed by the receiving surface (21) of the mold (20), that is, the receiving surface (21). In addition, an inlet portion (22a) of the molding cavity (22) is provided at the center of the receiving surface (21) (that is, the tip surface of the molding convex portion (26)). Further, the receiving surface (21) is slightly recessed in a substantially dish shape.

  Next, an upsetting method using the upsetting apparatus (10B) of the second embodiment will be described below.

  First, as shown in FIG. 8, the molding convex part (26) of the mold (20) is fitted into the molding concave part (15) at the tip of the guide (11). In this fitted state, the receiving surface (21) of the mold (20) (that is, the front end surface of the molding convex portion (26)) and the front end surface (13) of the guide (11) (that is, the bottom surface of the molding concave portion (15)). There is a slight gap between them. The length of the material (1) in the axial direction of this gap is the exposed portion (1) of the material (1) exposed between the receiving surface (21) of the mold (20) and the tip surface (13) of the guide (11). It is set to be less than the buckling limit length of 2).

  Further, the material (1) is inserted and arranged in the insertion hole (12) of the guide (11), and one end (1a) of the material (1) protruding from the material outlet (12a) of the guide (11) It arrange | positions facing the entrance part (22a) of the shaping | molding cavity (22) of a metal mold | die (20). In the present embodiment, one end portion (1a) of the material (1) is disposed in the inlet portion (22a) of the molding cavity (22) [arrangement step]. Moreover, a raw material (1) is heated beforehand as needed.

  Next, in this state, the small diameter portion forming step and the large diameter portion forming step are simultaneously performed.

  That is, as shown in FIGS. 9 to 12, the material (1) is pressed in the axial direction from the other end (1b) by the punch (31) of the material pressing means (30) (the pressing direction (P)). ), The guide (11) is moved in the direction (G) opposite to the pressing direction (P) of the material (1). As a result, the exposed portion (2) of the material (1) exposed between the receiving surface (21) of the mold (20) and the tip surface (13) of the guide (11) is expanded in the molding recess (15). Simultaneously with the diameter, the material of the material (1) pushed out from the material outlet (12a) of the guide (11) (specifically, the material of one end (1a) of the material (1)) is formed from the inlet (22a). Push into the cavity (22) [large diameter portion forming step and small diameter portion forming step].

  In this step, as shown in FIGS. 9 to 12, the filling of the material into the molding recess (15) takes precedence over the filling of the material into the molding cavity (22).

  When the material is filled in the molding cavity (22) and the movement of the guide (11) is stopped, if the material is filled in the molding recess (15), the process proceeds to the step shown in FIG. On the other hand, as shown in FIG. 12, when the material is filled in the molding recess (15) so that the unfilled part (N) not filled with the material remains in the corner, Proceed to the steps shown.

  In the step shown in FIG. 13, the guide (11) is moved in the same direction and at the same speed as the moving direction of the punch (31) (that is, the pressing direction (P) of the material (1)). ) And the tip surface (13) of the guide (11) (that is, the bottom surface of the molding recess (15)) press the material in the molding recess (15) together. Thereby, the material in the molding recess (15) is filled in the unfilled portion (N) in the molding recess (15), the unfilled portion (N) is extinguished, and the material is completely contained in the molding recess (15). To charge. Thereby, a large diameter part (7) is formed in the other end part (1b) of a raw material (1).

  Next, as shown in FIG. 14, the guide (11) is separated from the mold (20), and then the upset product (5B) is placed in the molding cavity (22) of the mold (20) by the knockout punch (40). The upsetting product (5B) shown in FIG. 15 is obtained by extruding from.

  Thus, according to the upsetting method of the second embodiment, the small-diameter portion forming step and the large-diameter portion forming step are simultaneously performed, so that the processing can be performed extremely efficiently.

  In the second embodiment, the small diameter portion forming step and the large diameter portion forming step are performed simultaneously. However, in the present invention, the large diameter portion forming step is performed after the small diameter portion forming step. Also good.

  Although several embodiments of the present invention have been described above, the present invention is not limited to those shown in the above embodiments, and various setting changes can be made.

  For example, in the above embodiment, the material pressing means (30) has the punch (31). In the present invention, however, the material pressing means (30) pivots the material (1) by a drive roller, for example. It may be configured to pressurize in the direction, or other pressurizing means.

  Moreover, in this invention, the site | part which forms a large diameter part (7) in a raw material (1) does not necessarily need to be the other end part (1b) of a raw material (1). ) In the middle in the axial direction.

  In the invention, the guide (11) and the mold (20) are not necessarily required to have the molding convex portions (14, 26) and the molding concave portions (15, 23). That is, the upsetting method of the present invention is a constrained upsetting method in which the exposed portion (2) of the material (1) is expanded in the molding recess (15, 23) as shown in the above embodiment. Alternatively, the exposed portion (2) of the material (1) may be freely expanded in a non-constrained state between the receiving surface (21) of the mold (20) and the tip surface (13) of the guide (11). It is also possible to use a machining method.

  INDUSTRIAL APPLICABILITY The present invention can be used for an upsetting method and an upsetting apparatus used for forming a small diameter portion and a large diameter portion in one end portion in the axial direction of the material and a portion on the other end side from the one end portion, respectively. is there.

It is sectional drawing of the upsetting apparatus in the state before processing a raw material which shows the upsetting apparatus of 1st Embodiment of this invention. It is sectional drawing of the upsetting apparatus in the state which filled the raw material material in the shaping | molding cavity of a metal mold | die. It is sectional drawing of the upsetting apparatus in the state in the middle of filling the raw material into the molding recessed part of a metal mold | die. It is sectional drawing of the upsetting apparatus in the state which filled the material of the raw material in the shaping | molding recessed part of a metal mold | die. It is sectional drawing of the upsetting apparatus in the state which pressurized the material in the shaping | molding recessed part of a metal mold | die. It is sectional drawing of the upsetting apparatus in the state in the middle of taking out an upsetting processed product from a metal mold | die. It is a perspective view of the upsetting product manufactured using the upsetting apparatus. It is sectional drawing of the upsetting apparatus in the state before processing a raw material which shows the upsetting apparatus of 2nd Embodiment of this invention. It is sectional drawing of the upsetting apparatus in the state in the middle of filling the raw material into the shaping | molding cavity and shaping | molding recessed part of a metal mold | die. It is sectional drawing of the upsetting apparatus in the state in the middle of further filling the raw material into the shaping | molding cavity and shaping | molding recessed part of a metal mold | die. It is sectional drawing of the upsetting apparatus in the state in the middle of further filling the raw material into the shaping | molding cavity and shaping | molding recessed part of a metal mold | die. It is sectional drawing of the upsetting apparatus in the state which filled the material of the raw material in the shaping | molding cavity and shaping | molding recessed part of a metal mold | die. It is sectional drawing of the upsetting apparatus in the state which pressurized the material in the shaping | molding cavity and shaping | molding recessed part of a metal mold | die. It is sectional drawing of the upsetting apparatus in the state in the middle of taking out an upsetting processed product from a metal mold | die. It is a perspective view of the upsetting product manufactured using the upsetting apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Raw material 1a ... One end part 1b ... Other end part 2 ... Exposed part 5A, 5B ... Upsetting product 6 ... Small diameter part 7 ... Large diameter part 10A, 10B ... Upsetting apparatus 11 ... Guide 12 ... Insertion hole 12a ... Material outlet part 13 ... tip face 14 ... molding convex part 15 ... molding concave part 16 ... peripheral wall part 20 ... mold 21 ... receiving surface 22 ... molding cavity 22a ... inlet part 23 ... molding concave part 24 ... peripheral wall part 25 ... groove part 26 ... molding Convex part 30 ... Material pressurizing means 31 ... Punch 35 ... Guide drive means 40 ... Knockout punch N ... Unfilled part

Claims (11)

It is an upsetting method for forming a small diameter portion and a large diameter portion in one end portion in the axial direction of the material and a portion on the other end side than the one end portion, respectively.
A rod-shaped material whose diameter is set between the diameter of the small diameter part and the diameter of the large diameter part,
A guide having an insertion hole for inserting and holding the material in a buckling-preventing state, and a material outlet portion formed of one end opening of the insertion hole on the distal end surface;
Using a mold having a molding cavity for forming a small diameter portion and a receiving surface, and a receiving surface provided with an inlet portion of the molding cavity,
An arrangement step of arranging the material in the insertion hole of the guide and arranging one end portion of the material protruding from the material outlet portion of the guide facing the inlet portion of the molding cavity of the mold,
After the placing step, by pressing the material in the axial direction, the material of the material extruded from the material outlet portion of the guide is pushed into the molding cavity from the inlet portion, and a small diameter portion forming step for forming a small diameter portion,
The material exposed between the receiving surface of the mold and the tip surface of the guide by moving the guide in a direction opposite to the pressing direction of the material while pressing the material in the axial direction after the arranging step. A large-diameter portion forming step of expanding the diameter of the exposed portion between the receiving surface and the tip end surface of the guide and forming a large-diameter portion;
The upsetting method characterized by including. The mold has a molding recess for forming a large-diameter portion, and the bottom surface of the molding recess is formed by a receiving surface of the mold.
At the tip portion of the guide, a molding convex portion corresponding to the molding concave portion of the mold is formed, and the tip surface of the molding convex portion is formed by the tip surface of the guide,
In the large-diameter portion forming step, the exposed portion of the material is expanded between the receiving surface of the mold and the tip end surface of the guide, so that the material of the exposed portion of the material is filled into the molding recess, and the large-diameter portion The upsetting method according to claim 1, wherein:   In the large-diameter portion forming step, the material of the exposed portion of the raw material is filled in the molding recess so that an unfilled portion not filled with the material remains in the corner, and then the unfilled portion in the molding recess The upsetting method according to claim 2, wherein the large-diameter portion is formed by pressurizing the material in the molding concave portion with the tip end surface of the guide so that the material is filled with the material. The tip of the guide is provided with a molding recess for forming a large diameter portion, and the bottom of the molding recess is formed by the tip of the guide,
The mold has a molding convex part corresponding to the molding concave part of the guide, and the tip surface of the molding convex part is formed by the receiving surface of the mold,
In the large-diameter portion forming step, the exposed portion of the material is expanded between the receiving surface of the mold and the tip end surface of the guide, so that the material of the exposed portion of the material is filled into the molding recess, and the large-diameter portion The upsetting method according to claim 1, wherein:   In the large-diameter portion forming step, the material of the exposed portion of the raw material is filled in the molding recess so that an unfilled portion not filled with the material remains in the corner, and then the unfilled portion in the molding recess The upsetting method according to claim 4, wherein the large-diameter portion is formed by pressurizing the material in the molding concave portion with the tip surface of the guide so that the material is filled with the material.   The upsetting method according to claim 1, wherein the large-diameter portion forming step is performed after the small-diameter portion forming step.   The upsetting method according to any one of claims 1 to 5, wherein the small diameter portion forming step and the large diameter portion forming step are performed simultaneously.   An upsetting product manufactured by the upsetting method according to claim 1. An upsetting apparatus for forming a small-diameter portion and a large-diameter portion at one end portion in the axial direction of the rod-shaped material and a portion on the other end side from the one end portion,
A guide having a through hole for inserting and holding the rod-shaped material in a buckling-prevented state, and a guide provided with a material outlet portion consisting of one end opening of the insertion hole on the tip surface;
A mold cavity having a small-diameter portion forming cavity for forming a small-diameter portion by reducing the cross-sectional area of one end portion of the material, and a receiving surface, and a mold provided with an inlet portion of the molding cavity on the receiving surface;
A material pressurizing means for pressurizing the material disposed in the insertion hole of the guide in the axial direction;
Guide driving means for moving the guide in a direction opposite to the pressing direction of the material,
With
The molding cavity of the mold forms a small diameter part by pushing the material of the material pushed out from the material outlet part of the guide by the material pressurizing means into the molding cavity from the inlet part,
The exposed portion of the material exposed between the mold receiving surface and the guide tip surface is expanded between the mold receiving surface and the guide tip surface to form a large diameter portion. An upsetting apparatus characterized by The mold has a molding recess for forming a large-diameter portion, and the bottom surface of the molding recess is formed by a receiving surface of the mold.
10. The upsetting apparatus according to claim 9, wherein the tip end portion of the guide is formed with a molding convex portion corresponding to the molding concave portion of the mold, and the tip surface of the molding convex portion is formed by the tip end surface of the guide. . The tip of the guide is provided with a molding recess for forming a large diameter portion, and the bottom of the molding recess is formed by the tip of the guide,
The upsetting apparatus according to claim 9, wherein the mold has a molding convex portion corresponding to the molding concave portion of the guide, and a tip surface of the molding convex portion is formed by a receiving surface of the mold.

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