JP3555384B2 - Variable cross section extrusion die and variable cross section extrusion molding method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a variable cross-section extrusion die suitable for use in extruding a tubular molded product whose cross-sectional shape changes along the longitudinal direction, particularly with a molding material such as aluminum, and a variable cross-section extrusion using the die It relates to a molding method.
[0002]
[Prior art]
2. Description of the Related Art In recent years, various types of vehicles such as general passenger cars, motorcycles, and trucks are excellent in weight reduction, durability improvement or recyclability of a vehicle body. As such a component, a member made of aluminum or an aluminum alloy is being used in place of a conventional member made of iron.
Usually, in manufacturing such various components, extrusion processing is employed because aluminum, which is a raw material, has a low melting point. This extrusion process fixes an extrusion die in which a die hole having a cross-sectional shape of the above-mentioned constituent member is perforated at the tip of the container, inserts a heated aluminum material (a billet) into the container, and inserts the billet into the container. The above-mentioned constituent member is formed by being pressed to the extrusion die side by a pressing machine (stem) and extruding from the die hole. By the way, according to the extrusion process, since the die hole of the extrusion die has a constant cross-sectional shape, the obtained constituent member is also formed into a constant cross-sectional shape in the longitudinal direction.
[0003]
By the way, as such various constituent members, H-shaped or T-shaped members having a web and a flange portion are mainly used as a shape capable of obtaining a predetermined mechanical strength, in other words, a high second moment of area. However, both have the disadvantage that the outer shape of the cross-sectional shape becomes large, which hinders space saving, and there is a problem that the flange portion interferes with other mounting members depending on the place of use. The use of a square tubular member having a smaller external method and excellent mechanical strength is being studied in place of the T-shaped member.
[0004]
[Problems to be solved by the invention]
However, in the above-mentioned conventional extrusion die, since the die hole has a constant cross-sectional shape, the rectangular tubular member also has a constant cross-sectional shape in the longitudinal direction. On the other hand, in this type of component, usually, the distribution of the acting bending stress varies along the longitudinal direction, so that a portion where a large bending stress does not act eventually has an unnecessary dimension and strength, Therefore, there is a problem that the molding material is wasted, which is uneconomical, and that the originally desired installation space cannot be made compact and lightweight.
[0005]
Therefore, in order to solve such a problem, it is conceivable to use an extrusion molding die as shown in, for example, International Publication No. WO93 / 00183.
FIGS. 14 and 15 show a conventional extrusion molding die disclosed by the above-mentioned international publication, and this extrusion molding die is originally for extruding a copper deformed uneven thickness pipe, In the drawing, reference numeral 1 denotes a container, 2 denotes a mandrel, 3 denotes a pressurizing ram, 4 denotes a billet, and a die 5 is provided at an opening at the tip of the container 1. The apparatus is provided with a die cross section variable device 6 which is made to appear and disappear in the die 5.
According to the above-mentioned conventional extrusion die, while the billet 4 in the container 1 is pushed out of the die hole of the die 5 by the pressing ram 3, the hydraulic cylinder 8 of the die cross section variable device 6 is appropriately operated to make the plate-shaped extrusion member. By making the 7 project into and out of the die hole of the die 5, a tubular member 10 having a variable cross-section and having projections 9 at desired locations on the outer peripheral portion as shown in FIG. 15 can be formed.
[0006]
However, when trying to apply the above-mentioned conventional extrusion die to the formation of various square tubular components as described above, the inner diameter (inner method) is constant in the longitudinal direction by the mandrel 2, whereas Since the protrusions 9 are formed only in the portions requiring mechanical strength, the protrusions 9 protrude only in those portions, and the wall thickness becomes unnecessarily large, so that the molding material is wasted and the weight is sufficiently light. In addition, there is a problem that the protrusion 9 cannot be achieved, and since the protrusion 9 is formed locally, there is a problem that the protrusion 9 obstructs the mounting structure.
[0007]
Therefore, it is conceivable to use a tapered mandrel instead of the mandrel 2. According to this tapered mandrel, the inner diameter of the tubular member can be changed by moving the tapered mandrel back and forth in parallel with the extrusion of the aluminum material.
However, even when such a tapered mandrel is used, it is difficult to uniformly form the wall thickness of the entire tubular member, and further, in order to drive the tapered mandrel, the entire device becomes complicated, There was a problem that control became extremely difficult.
[0008]
The present invention has been made to effectively solve the problems of such a conventional extrusion die and an extrusion molding method using the same. When extruding a molding material such as aluminum, complicated devices and controls are required. Die for variable section extrusion capable of extremely easily forming a tubular member in which the outer method and the inner method are freely changed in the longitudinal direction without causing intrusion, and variable section extrusion molding using the extrusion die Its purpose is to provide a method.
[0009]
[Means for Solving the Problems]
The variable cross-section extrusion die according to the first aspect of the present invention (hereinafter, abbreviated as an extrusion die) includes a first die and a second die that are sequentially arranged in the extrusion direction of a molding material. The first and second dies are provided with a first die hole and a second die hole, which define an outer shape of the tubular member by communicating portions with each other, and the first die hole is provided with the first die hole. A first core portion is disposed between the first die hole and at least one side wall of the first die hole via a gap, and at least one side wall of the second die hole is provided in the second die. And a second core portion that is integrally movable with the second die via a gap between the first die portion and the second core portion in the pushing direction. at least a portion of the first and second die hole communicated with the annular, intersecting the extrusion direction It is characterized in that that is the direction provided freely move relatively.
[0010]
Here, the invention according to claim 2 is characterized in that the first and second die holes are formed in a rectangular shape having the same short side length, and the first core portion is formed of the first die. The second core portion is disposed on a side wall of one short side of the hole, and the second core portion is disposed on a side wall side of the other short side of the second die hole. The die is characterized in that the long sides of the first and second dice holes are aligned with each other, and the dies are relatively movable along the long side walls.
According to a third aspect of the present invention, at least one of the first and second core portions according to the first or second aspect is provided with a plurality of small core portions arranged with a gap along the side wall. Is characterized in that it is divided into
[0011]
Further, in the invention according to claim 4, in the invention according to any one of claims 1 to 3, the first die is a fixed female die in which a fixed die hole serving as a first die hole is formed. And a fixed die serving as a first core portion is disposed in the fixed die hole, and the second die is provided with a slide die hole formed as a second die hole. And, in the slide die, a connecting portion curved from the surface thereof to the upstream side in the extrusion direction extends, and the distal end of the connecting portion has a gap between the slide die and the side wall of the slide die hole. A base end portion of a slide core serving as the second core portion disposed in the slide die hole is provided integrally.
[0012]
According to a fifth aspect of the present invention, the slide core according to the fourth aspect is disposed on the fixed core in a stacked manner, and a hole is formed in a side wall of the fixed core. A base end of the slide core is slidably inserted into the hole.
[0013]
Next, the variable cross-section extrusion molding method according to the present invention according to claim 6 is a variable cross-section extrusion molding method for forming a tubular member whose cross-sectional shape changes in the extrusion direction. Using the extrusion die according to any of the above, the first die and the second die are relatively moved while extruding a molding material toward the extrusion die, and the first and second dies are mutually moved. 8. The method according to claim 7, wherein an outer shape of the tubular member is formed by a communicating portion of the second die hole, and an inner shape of the tubular member is formed by the first and second core portions. The present invention is characterized in that the molding material is aluminum or an aluminum alloy.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of an extrusion die of the present invention will be described with reference to the drawings.
FIGS. 1 to 6 apply the extrusion die according to the present invention to a die having a rectangular cross section as shown in FIG. 10 and capable of forming a tubular member whose cross sectional shape changes in the extrusion direction. 1 illustrates one embodiment.
In these figures, this extrusion die is composed of a fixed male die 10, a fixed female die (first die) 11, and a slide die (sequentially arranged in a laminating manner in the extrusion direction of aluminum or aluminum alloy as a molding material. (A second die) 12. In the center of the lower surface of the fixed female die 11, a rectangular fixed die hole (first die hole) 13 as shown in FIG. 6 is formed. The fixed male die 10 is integrally formed with a die base portion 14 protruding from the lower surface 10a in the figure toward the fixed die hole 13 side, and a male die 15 is formed on the lower surface of the die base portion 14. Have been.
[0015]
In this male die 15, a substantially square fixed core (first core portion) 16 formed at the lower end portion thereof has a gap S of a predetermined dimension with one short side bearing portion side wall 13 a of the fixed die hole 13. It is formed at an eccentric position of the die base portion 14 so that the die base portion 14 is disposed. Here, a gap having the same size is also formed between the fixed core 16 and the long side 13b of the fixed die hole 13. Around the die base portion 14 of the fixed male die 10, channels 17 are formed for guiding an aluminum material sent from a container (not shown) to the fixed die hole 13. The slide die 12 is slidably provided on the lower surface of the fixed female die 11.
[0016]
On the upper surface of the slide die 12, a rectangular slide die hole (second die hole) 18 of the same shape as shown in FIG. Further, on the upper surface of the slide die 12, as shown in FIGS. 1 to 4, a connecting portion 19 that curves to the upstream side in the extrusion direction is formed. It is formed integrally. The base end portion 21 is formed in a T-shape, and a slide core (second core portion) 20 is formed integrally with a lower end portion thereof. As shown in FIG. 5, the slide core 20 is formed in a substantially square shape having the same shape as the fixed core 16, and a gap is formed between the slide core 20 and the other short side bearing portion side wall 18a of the slide die hole 18. It is arranged in the slide die hole 18 via S. Here, the gap S is set to have the same size as the gap S between the fixed core 16 and the fixed die hole 13, and between the slide core 20 and the long side 18 b of the slide die hole 18. A gap having the same dimensions is also formed in the second embodiment.
[0017]
Here, as shown in FIG. 4, a T-shaped hole 22 is formed in the side wall of the male die 15 of the fixed male die 10, and the T-shaped hole 22 of the slide core 20 is formed in the hole 22. The base end 21 is slidably inserted. As a result, the slide cores 20 are arranged on the fixed core 16 in a stackable manner so as to be overlapped, and are slidably arranged on the fixed core 16.
Then, the slide die 12 aligns the long side 18b of the slide die hole 18 with the long side 13b of the fixed die hole 13 and drives the unillustrated hydraulic cylinder or the like along the long sides 13b, 18b by a driving device such as a hydraulic cylinder. It is provided movably in the direction orthogonal to the extrusion direction with respect to the fixed female die 11.
[0018]
Next, an embodiment of the variable cross-section extrusion molding method according to the present invention using the extrusion die having the above-described configuration will be described with reference to FIGS. 7 to 9 show the relative positional relationship between the fixed die hole 13 and the fixed core 16 and the slide die hole 18 and the slide core 20 when the slide die 12 is moved, respectively. Portions indicated by hatching indicate respective opening portions, and portions where both hatchings overlap indicate a cross-sectional shape of a tubular member formed by extrusion.
[0019]
First, by adjusting the position of the slide die 12 and performing extrusion molding with the slide core 20 aligned with the fixed core 16 as shown by the solid line in FIG. , And further around the connecting portion 19 located on the upstream side of the fixed die hole 13, and is pushed out from the communicating portion between the fixed die hole 13 and the slide die hole 18. Thereby, as shown in FIG. 7, the square tubular portion 31 in the tubular member 30 shown in FIG. 10 is extruded by the communicating portion between the fixed core 16 (slide core 20), the fixed die hole 13 and the slide die hole 18. You. Incidentally, the thickness of the tubular portion 31 is formed to have the same size as the gap S.
[0020]
Next, when the slide die 12 is gradually moved to the left in the figure by a driving device (not shown), the base end 21 of the slide core 20 slides in the hole 22 of the male die 15, as shown in FIG. As shown, the slide core 18 also moves on the fixed core 16 integrally with the slide die 12. As a result, in the tubular member 30 shown in FIG. 10, a tubular portion 32 whose width dimension gradually increases is extruded.
Then, as shown in FIG. 9, at the position where the fixed core 16 and the slide core 18 are continuous, the widest portion 33 of the tubular member 30 is extruded. Next, the extrusion of the entire tubular member 30 shown in FIG. 10 is completed by gradually moving the slide die 12 to the left in the drawing by the driving device, contrary to the above process.
[0021]
As described above, according to the extrusion die, the slide die 12 is formed with the connecting portion curved from the surface thereof to the upstream side in the extrusion direction, and the connection portion forms the gap S between the slide die 12 and the slide die hole 18. Since the slide cores 20 are integrally connected to each other, the aluminum material flowing into the space around the male die 15 from the flow path 16 is wrapped around the connection portion 19 to form the fixed die hole 13. And the slide die hole 18 can be guided.
As a result, by simply moving only the slide die 12, the slide die hole 18 and the slide core 20 are integrally moved, and the communicating portion between the slide die hole 18 and the fixed die hole 13 and the fixed core 16 is shown in FIG. Since such a tubular member 30 can be extruded, the thickness is constant in the longitudinal direction and various variable cross-sections can be achieved without the need for a separate device such as a tapered mandrel that complicates control. The tubular member 30 having a shape can be formed very easily without complicating the apparatus and the extrusion control.
[0022]
In addition, the slide core 20 is disposed on the fixed core 16 in a stacked manner, and the base end 21 of the slide core 20 is slidably inserted and held in the hole 22 formed in the side wall of the male die 15. Therefore, the slide core 20 can be slid in a stable manner, so that the molding accuracy of the tubular member 30 can be further improved.
[0023]
In the above-described embodiment, one substantially square fixed core (first core portion) 16 is provided in the male die 15 with a gap of a predetermined size from the bearing portion side wall 13 a on one short side of the fixed die hole 13. S, and one slide core (second core portion) formed in a substantially square shape having the same shape as the fixed core 16 on the other slide die 12 on the other short side of the slide die hole 18. Although only the case where it is formed integrally with the bearing portion side wall 18a via the gap S has been described, the present invention is not limited to this. For example, as in another embodiment shown in FIG. As a result, two small fixed cores (small core portions) 40, 40 are formed in parallel with one short side of the fixed die hole 13 with a predetermined gap S therebetween. 2 cores of the same shape as 2 cores Slide core may be parallel form via a predetermined gap S between the (small core portion) 41, 41 in the same manner as the slide die hole 18.
[0024]
According to this extrusion die, a reinforcing rib 42 is formed in the center of the inside, and a cylindrical member having a constant thickness in the longitudinal direction and a cross-sectional shape that changes can be extruded. . Therefore, if three small cores are formed, it is possible to extrude a tubular member having a square cross section with two ribs formed therein.
[0025]
In the above embodiment, the fixed die hole 13 and the slide die hole 18 are formed in the same rectangular shape, and the slide die 12 is fixed to the fixed female die 11 in a state where the long sides 13b and 18b are aligned with each other. Although the case where the movable member is provided movably has been described, the present invention is not limited to this, and the outer shape of the molded body is always defined by the fixed die hole 50 as in the other embodiment shown in FIG. The slide die hole 52 of the slide die 51 is formed to have a size larger than that of the fixed die hole 50, and a fixed core 53 is provided at the center of the fixed die hole 50. Alternatively, the slide core 54 may be formed integrally with the slide die 51.
[0026]
According to this extrusion die, the slide die 51 is moved, and the slide core 54 formed integrally with the slide die 51 is moved obliquely with respect to the fixed core 53 as shown by an arrow in the drawing. This makes it possible to extrude a tubular member having a constant outer shape in the longitudinal direction and a variable thickness.
[0027]
Further, as in the other embodiment shown in FIG. 13, a fixed core portion 61 is provided at a corner of the fixed die hole 60 via a side wall and a gap S, and a slide die hole 62 having the same shape as the fixed die hole 60. A similar slide core 63 is integrally disposed at the corner of the slide die 62 and the slide die 62 and the slide core 63 are moved in a diagonal direction as indicated by an arrow in the drawing, so that the thickness is substantially reduced in the longitudinal direction. A tubular member whose outer shape and thickness change so as to be constant may be extruded.
[0028]
【The invention's effect】
As described above, according to the extrusion die according to any one of claims 1 to 5 and the variable cross-section extrusion molding method according to claim 6 or 7 using the extrusion die, relative to the first die. The second die provided movably is integrally movable with the second die via a gap between at least one side wall of the second die hole and the first die. Since the second core portion which can be overlapped in the direction is provided, the second die hole can be formed by simply moving only the first die or the second die relatively without using a taper mandrel or the like. And the second core portion are relatively moved, so that the first die hole and the communicating portion with the first core portion can extremely easily form a constant thickness in the longitudinal direction and various variable cross-sectional shapes. Extruding a tubular member having It can be.
Therefore, it is particularly suitable for use in the case where aluminum or an aluminum alloy is used as a molding material to extrude body components in various vehicles such as general passenger cars and motorcycles, as in the invention according to claim 7. is there.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing one embodiment of an extrusion die according to the present invention.
FIG. 2 is a plan view of FIG.
FIG. 3 is a front view showing a main part of the slide die of FIG. 1;
FIG. 4 is a side view showing a main part of the male die of FIG. 1;
FIG. 5 is a plan view showing a shape of a slide die hole portion of FIG. 1;
FIG. 6 is a plan view showing a shape of a fixed die hole portion of FIG. 1;
FIG. 7 is a plan view showing a positional relationship between a slide die hole and a fixed die hole.
FIG. 8 is a plan view showing a positional relationship when the slide die hole of FIG. 7 is moved.
FIG. 9 is a plan view showing a positional relationship when a tubular portion having a maximum sectional area is formed by a slide die hole and a fixed die hole.
FIG. 10 is a perspective view showing a tubular member formed by the movement shown in FIGS. 7 to 9;
FIG. 11 is a plan view showing the shape of both die hole portions in another embodiment of the present invention.
FIG. 12 is a plan view showing the shape of both die hole portions in another embodiment of the present invention.
FIG. 13 is a plan view showing a shape of both die hole portions in a modification of FIG.
FIG. 14 is a longitudinal sectional view showing a conventional extrusion molding apparatus.
FIG. 15 is a perspective view showing a structural member molded by the extrusion molding apparatus of FIG.
[Explanation of symbols]
10 Fixed male die 11 Fixed female die (first die)
12 Slide dice (second die)
13, 50, 60 Fixed die hole (first die hole)
13a One short side wall 13b Long side 15 Male dies 16, 53, 61 Fixed core (first core portion)
18, 52, 62 Slide die hole (second die hole)
18a Other short side wall 18b Long side 19 Connecting part 20, 54, 63 Slide core 21 Base end part 22 Hole part 40, 41 Small core part

Claims (7)

A variable cross-section extrusion die capable of forming a tubular member whose cross-sectional shape changes in the extrusion direction,
A first die and a second die are sequentially arranged in the extrusion direction of the molding material, and the first and second dies have a communicating portion that defines an outer shape of the tubular member with a communicating portion therebetween. A first die hole and a second die hole are formed, and a first core portion is inserted into the first die hole with a gap between at least one side wall of the first die hole. Is disposed on the second die, and is movable integrally with the second die via a gap between at least one side wall of the second die hole and the first core portion. And a second core portion that can be overlapped in the extrusion direction is provided. The first and second dies communicate at least a part of the first and second die holes in a ring shape, and Characterized by being provided so as to be relatively movable in a direction crossing the direction. Variable cross-section extrusion die for that. The first and second die holes are formed in a rectangular shape having the same short side length, and the first core portion is formed on one side of the short side wall of the first die hole. And the second core portion is disposed on a side wall side of the other short side of the second die hole, and the first and second dies are connected to each other by the first and second dies. 2. The variable cross-section extrusion device according to claim 1, wherein the first and second die holes are provided so that the long side walls thereof are aligned and relatively movable along the long side walls. 3. dice. 3. The device according to claim 1, wherein at least one of the first and second core portions is divided into a plurality of small core portions disposed along the side wall with a gap therebetween. Die for variable section extrusion. The first die is a fixed female die in which a fixed die hole serving as the first die hole is formed, and a fixed core serving as the first core portion is provided in the fixed die hole. The second die is a slide die in which a slide die hole serving as the second die hole is formed, and the slide die is curved from a surface thereof to an upstream side in the extrusion direction. A connecting portion extends, and a base of a slide core serving as the second core portion disposed in the slide die hole via a gap between the connecting portion and the side wall of the slide die hole. The variable cross-section extrusion die according to any one of claims 1 to 3, wherein the end is provided integrally. The slide core is disposed on the fixed core in a stacked state, and a hole is formed in a side wall of the fixed core, and a base end of the slide core is slidably inserted into the hole. The variable cross-section extrusion die according to claim 4, wherein the die is inserted. A variable cross-section extrusion molding method for forming a tubular member whose outer dimensions and inner dimensions change in the extrusion direction, wherein the variable cross-section extrusion die according to any one of claims 1 to 5 is used. The first die and the second die are relatively moved while extruding a molding material toward a variable cross-section extrusion die, and the tubular member is moved by a communicating portion between the first and second die holes. And forming an inner shape of the tubular member using the first and second core portions. The method according to claim 6, wherein the molding material is aluminum or an aluminum alloy.

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