KR100286124B1 - Combination dice for extrusion processing and extrusion processing - Google Patents

Abstract

The present invention relates to an auto-combination die and an extrusion processing method which can easily manufacture and process the core 12 while alleviating the stress concentration of the core support, thereby maintaining strength reliability, and supporting the side portion of the core 12. A hole 16 is formed, the support pin 13 is disposed through the support hole 16 in a state in which both ends thereof protrude outward, and both ends 13a and 13a of the pin 13 are held in the middle. The core 12 is formed in a male structure in which the core 12 is held by the holding mold 14 by being supported by the supporting ends 23 and 23 inside the holding hole 21 of the mold 14.

Description

Combination dies for extrusion processing and extrusion processing

1A is a horizontal sectional view showing a combination dice according to the first embodiment;

1b is a cross-sectional view taken along the line 1-1 of FIG. 1a,

2 is an exploded perspective view showing the die of FIG.

3A is a horizontal sectional view showing a combination dice according to the second embodiment;

3b is a cross-sectional view taken along line 3-3 of FIG. 3a,

4 is a perspective view showing an exploded die of FIG.

5 is a rear cross-sectional view of the die of FIG. 3 with the lid member removed;

6 is a partial cross-sectional perspective view showing a support state of a core in the die of FIG.

FIG. 7a is a cross-sectional view taken along the line 5-5 of FIG.

7b is a cross-sectional view taken along line 6-6 of FIG. 5,

7c is a cross-sectional view taken along the line 7-7 of FIG.

8A to 8G show the shapes of the cores of various shapes, cross-sectional views taken along the lines 8-8 of FIGS. 2 and 4,

9 is a cross-sectional view of the support pin,

10 is a cross-sectional view showing a separation state of the core and the support pin as a third embodiment,

11 is a perspective view illustrating a state in which a core and a support pin are separated as a fourth embodiment;

12 is a sectional perspective view of a tube material for a heat exchanger which is an embodiment of the manufacturing target,

13A is a plan view illustrating a rear end portion of a bridge portion for explaining the second embodiment;

13b is a cross-sectional view taken along the line 13-13 of FIG. 13a,

14a is an exploded perspective view of a conventional die,

14b is a perspective view of a conventional core,

14C is a perspective view of a conventional core.

<Explanation of symbols for main parts of drawing>

1: tube material 2: dies

3: figure 4: male

12 core 14 core holding mold

15: hollow molded part 16: support hole

[Purpose of invention]

[Technical field to which the invention belongs and the prior art in that field]

The present invention is a herb combination die and extrusion method widely used for extrusion processing of various small, medium or large extrusion materials, including, for example, multi-bored flat tube materials for aluminum heat exchangers. It is about.

As shown in FIG. 12, for example, the manufacture of the aluminum tube material 1 for heat exchanger of an air conditioner has been conventionally performed by various methods, but the manufacturing by extrusion method can provide the tube excellent in pressure-resistance performance etc. among these. It has the advantage of being attracting attention.

In the extrusion method, a combination die consisting of a die, generally a male mold for forming the hollow part in the tube member 1, and a female mold for molding the outer peripheral part of the tube member 1, for example, a port hole. Porthole dies and the like are used.

This combination die has a high die strength since the width B of the heat exchanger tube 1 is a very small and sophisticated hollow hollow flat die material such as 10 to 20 mm and a height H, for example, 3 to 7 mm. In order to reduce the cost caused by the die exchange due to friction or the like, the die structure is also shown in FIG. 14A to facilitate the manufacture of a compact die. As described above, the improvement in which the male 52 combined with the female 51 is divided into a core 54 having a hollow molded part 53 at its tip and a retaining mold 55 holding the core 54 are provided. Has been made. Similar considerations have been made to extrusion dies for medium and large materials.

In the combination die which adopts the male of this divisional configuration type, various samples have been conventionally proposed as a means for holding the core 54 to the holding die 55.

In the combination die shown in Fig. 14A, in the male die 52, the flat core 54 is configured such that the supporting protrusions 60, 60 protruding in the thickness direction thereof are integrally installed at the outer end thereof. The support protrusions 60 and 60 are configured to be held by the holding die 55 by being supported by the supporting end portions in the holding holes 58 of the core holding die 55.

Moreover, in the die shown in FIG. 14B, the male 52 is configured such that the support protrusions 57 and 57, in which the core 54 protrudes in the width direction thereof, are integrally provided at both ends thereof. The side protrusions 57 and 57 are configured to be supported by a supporting end in the holding hole 58 of the holding mold 55.

In the die shown in Fig. 14C, the male die 52 has a tapered shape in which the core 54 is tapered, and the holding hole 58 of the core holding mold 55 is also tapered. It is formed so that it is comprised so that both may fit in a taper.

However, in the structure shown in Fig. 14A, the shape of the core 54 is three-dimensional in particular because the support protrusions 60 and 60 of the core 54 are configured to protrude in the thickness direction of the core 54. As a result, it is complicated and the machining becomes very difficult, and the machining cost is high. In addition, there is a risk that cracks are generated in the portion where the outer protrusions 60 and 60 adhere to each other by stress concentration during extrusion, and the strength is not necessarily high.

In addition, in the structure shown in FIG. 14B, since the core 54 can be fabricated and fabricated using a flat plate material, there are few difficulties in fabrication. However, the outer protrusions 57 and 57 are formed by stress concentration during extrusion. There is a drawback that the strength reliability is considerably low such as cracking easily occurs on the adhered portion, resulting in an increase in the number of replacement of the core 54.

In addition, in the tapered-fitting structure shown in Fig. 14C, in order to accurately set the relative positional relationship of the core 54 in the extrusion direction with respect to the holding die 55, high precision is achieved in the taper shape of the core 54, particularly in die making. Is required, resulting in an increase in processing cost for the die.

The present invention eliminates the above-mentioned drawbacks and can facilitate the manufacture of the male, in particular the core, on the premise that the male is divided into a core, a holding die, and a combination die of the type and an extrusion process using the same. At the same time, the main object of the present invention is to provide a combination die for extrusion processing which does not require a very high precision machining as in the prior art, and an extrusion processing method which can realize advantageous extrusion processing in terms of cost and improvement in strength and reliability. It is done.

In the above object, the present invention is an extrusion combination die consisting of a combination of a male shape for forming the outer peripheral portion of the hollow material and a male shape for forming the hollow material hollow portion, wherein the male has a hollow molded portion at the front end, A core holding hole having a core having a support hole or a support recess formed therein, a support piece inserted into the support hole or the support recess of the core so as to protrude outwardly, and a support end facing the rear side in the extrusion direction. And the core is inserted into the holding hole of the mold in such a state that the core is supported at the supporting end of the holding mold holding hole by the outer projection of the core supporting piece inserted into the supporting hole or the supporting recess. The combination die for extrusion processing characterized by the above-mentioned.

In this case, the support piece is made of a pin, and the support pin is inserted into the support hole or the support recess of the core in an outwardly protruding state, and at the same time, the outer protruding end of the support pin is formed in the retaining mold holding hole. It is preferable that it is supported by the support end part.

The support pin preferably protrudes outward from the outer end opening position of the core holding hole or is disposed close to the opening position.

At least the inner circumferential surface of the support hole or the support recess portion of the core in the extrusion direction is formed as an arcuate main surface, and at least the outer circumferential surface of the support portion of the support pin or the insertion portion to the support recess portion is also a support hole or It is preferable that it is formed with the circular arc main surface corresponding to the said circular arc main surface of a support recessed part.

In this case, it is preferable that the arcuate outer peripheral surface of the back side of the support pin in the extrusion direction is formed beyond the semi-circumference.

The core is preferably made of a cemented carbide material such as cemented carbide.

The core holding hole is formed with respect to the bridge portion crossing the material distribution hole of the core holding mold, and the unevenness is fitted to the rear end surface of the bridge portion and the front end surface of the lid member disposed at the rear portion of the bridge portion. It is preferable that the lid member is disposed at the rear portion according to the fitting of the concave portion and the convex portion.

Another invention is an extrusion combination die composed of a combination of a male shape for forming a hollow material outer peripheral portion and a male shape for forming the hollow material hollow portion, the male having a hollow molded portion at the front end and at the same time a support hole or For core holding formed with a core having a support recess portion, a support piece inserted into the support hole or the support recess portion of the core in an outwardly protruding state, and a core holding hole having a support end portion facing the rear side in the extrusion direction. A combination provided with a mold, the core being inserted into the holding hole of the mold in a state in which the outer projection of the core support piece inserted into the supporting hole or the supporting recess is supported by the supporting end of the holding mold holding hole; The extrusion processing method characterized by extruding using a dice is made into the summary.

In this method, the supporting piece of the die to be used is made of a pin, and the supporting pin is inserted into the supporting hole or the supporting recess of the core in an outwardly protruding end portion, and the outer protruding end of the supporting pin is It is preferable to be supported by the supporting end of the holding mold holding hole.

Next, an embodiment in which the present invention is applied to a combination die and an extrusion processing method for use in the extrusion process of the aluminum tube material 1 for heat exchanger as shown in FIG. 12 will be described.

In addition, it goes without saying that the present invention can be widely applied to extrusion processing of various extruded materials such as small, medium and large size in addition to the heat exchanger tube material.

This is widely applied to various male combination dies of the type in which the male die is divided into the core and the mold for holding the core, and the extrusion processing method using the die.

[First Embodiment]

In the combination dice 2 shown in Figs. 1 and 2, reference numeral 3 is shaped like a child, and reference numeral 4 is male.

In the male die 4, reference numeral 12 is a core, reference numeral 13 is a support funnel as a support piece, reference numeral 14 is a core holding mold, and reference numeral 25 is a lid member.

The core 12 is produced by processing a flat plate material such as die steel, cemented carbide or ceramic. That is, the comb-shaped hollow molded part 15 which forms the hollow part 1a of the tube material 1 is formed in the tip part by a conventional method, for example, electric discharge machining. Moreover, the circular support hole 16 penetrates by the wire cut discharge part in the center part of the width direction which is near the outer edge part of the side surface part.

In addition, the core 12 may be machined into right and acute angles at the four corners of the cross section of the middle portion thereof, as shown in FIG. 8A, but may be sloped as shown in FIGS. 8B to 8E. It is preferable to work in an obtuse angle shape or roundish process in that the damage to the core 12 or the like due to stress concentration can be prevented. In addition, the eighth f may be processed into a shape as shown in the eighth g.

The support pin 13 is a plane in the form of an arc main surface over one half of its entire length on one side of the main axis surface of the base material of the same material as the core 12, as shown in FIGS. 1A, 1B and 2. The part 17 is processed. The length is longer than the thickness of the core 12, and both ends thereof protrude outward to a predetermined length in a state of being disposed through the support hole 16 of the core 12. Moreover, the diameter is made so that it may correspond substantially to the diameter of the core support hole 16, and it is comprised so that the support pin 13 may be inserted in the core support hole 16 in a suitable state.

The core holding die 14 is provided with a bridge 20 in a shape that traverses the extrusion material through hole 19 of the shaft center portion, and the through hole 19 has left and right material through holes 18 and 18. It is a mold of an integral molding divided into parts. The bridge 20 is formed with a core holding hole 21 for holding the core 12 in a shape that penetrates this in the extrusion direction.

The core holding hole 21 is formed such that its inner circumferential cross sectional shape substantially coincides with the cross sectional shape of the core 12, and is configured to be inserted into the core holding hole 21 in a substantially suitable state.

Further, each of the inner circumferential surface center portions of the width direction of the core holding hole 21 is formed with guide grooves 22 and 22 having a predetermined depth spreading from the outer end to the front end side in a mutually arranged relationship with each other. Flat end portions 23 and 23 are formed in the support. The width of the grooves 22 and 22 for the guide is formed to match the diameter of the support pins 13, and the support pins 13 protrude in a suitable state in the guide grooves 22 and 22 at both ends thereof. It is comprised so that insertion state may be carried out in the inner direction of the holding hole 21 in a state.

On the rear end surface of the bridge 20 of the core holding mold 14, a lid member fitting recess 26 for retracting inwardly the mold 14 and inserting the lid member 25 therein is formed. In addition, both ends of the fitting recess 26 are formed with concave grooves 27 and 27 extending in the front and rear directions for positioning in the rotational direction with respect to the lid member 25. 25 is configured to fit within the fitting recess 26.

The lid member 25 is an elliptic member, the rear side of which is formed in the shape of a mountain, and is configured so that the extruded material is smoothly classified into both material through holes 18 and 18 of the holding die 14.

In the assembly of the male 4, the support pin 13 is first inserted into the support hole 16 of the core 12 in a penetrating state. In this case, the support pin 13 arranges the flat part 17 in the support hole 16 in the extrusion direction. Then, the core 12 is inserted into the holding hole 21 from the rear of the holding mold 14, and both ends 13a and 13a of the support pin 13 are disposed on the flat portion 17. The support end 23 in the holding hole 21 is brought into contact. By this contact, the relative position of the core 12 and the holding | maintenance die 14 front-back direction is correctly determined, and the shaping | molding part 15 of the front-end | tip of the core 12 is as set in the front end surface of the holding mold 14 It protrudes by a predetermined length and is maintained. Then, the lid member 25 is fitted into the fitting recess 26 at the rear of the core holding mold 14, and the lid member 25 is fixed to the mold 14 by welding or the like.

By assembling the male mold 4 assembled as described above with the female mold 3, it is assembled to the extrusion die 2, and the tube material (between the tip molding part 15 of the core 12 and the female mold hole 5) is formed. Continuous slits 29 corresponding to the cross-sectional shape of 1) are formed. The combination die 2 is incorporated into an extruder, and the porous flat tube material 1 is extruded in front of the die by extrusion processing through an extruded material such as aluminum billet metal.

Further, the female mold 3 is adjacent to the female body mold 6 having the elliptical flat molding hole 5 for forming the outer circumferential portion of the tube member 1 and the rear side in the extrusion direction of the female body mold 6. The welding chamber forming mold 8 which forms the welding chamber 7 which joins and welds the extruded material group divided | segmented through the male mold 4, and the cylindrical shape which accommodates both metal mold | die 6 and 8 It is comprised so that it may hold | maintain in rotation direction by the fitting of the convex part 10 and 10 and the recessed part 11 and 11 in the accommodating metal mold | die 9.

In the extrusion die 2 having the above-described configuration, since the core 12 in the male die 4 only forms the support holes 16 for the flat plate material in order to hold it in the holding die 14, the core is manufactured. Can be made very easy, and the cost reduction can be realized, and further, the die cost and the extrusion processing cost can be realized. Particularly, since the core made of cemented carbide materials such as cemented carbide and ceramics can be easily processed and manufactured, its advantageous properties are exhibited.

In addition, it does not require precise high precision machining as in the case of the conventional taper-fitting core holding structure as shown in FIG. 14C, and can exhibit advantages in terms of better cost.

Furthermore, since the core 12 is supported by the support pin 13, the strength and reliability can be easily improved, and the number of times of core replacement can be greatly reduced.

In particular, the support hole 16 is formed into a circular hole, and is configured such that the arcuate inner circumferential surface of the support hole 16 is supported on the arcuate circumferential surface of the columnar pin 13 during extrusion, thereby being extruded. The stress concentration acting on the heavy core 16 is greatly alleviated, so that the strength and reliability of the die 1 can be made very high. In addition, since the core 12 can perform a slight swinging motion around the support pin 13, it can be self-aligned without difficulty, thereby achieving a more reliable die in strength. .

Moreover, since the circular arc main surface part except the flat part 17 of the support pin 13 is comprised so that the accompaniment of the pin 13 may be left, the support end part 23 and the pin 13 in the holding hole 21 will be left. Even if the planar portion 17 of the core 13 does not come into contact in a completely parallel state, the arcuate main surface portions at both ends of the pin 13 are maintained in the guide groove portion 22 of the retaining mold 14, whereby the core ( 12) is supported in the correct supporting direction, and can also prevent core breakage during extrusion due to misalignment of the supporting direction.

In addition, the support pin 13 is formed with a flat portion 17 over its entire length, and the flat portion 17 is configured to be in contact with the support end 23 of the retaining hole 21. Both ends of the support are stably supported by the support ends (23, 23).

However, setting the relative positional relationship between the core forming portion 15 and the self-forming hole 5 can change the cutting depth of the planar portion 17 of the support pin 13, as shown in FIG. It is possible to easily position or change the position of the core molding portion 15 relative to the molding hole 5.

Second Embodiment

The die according to the second embodiment relates to the improvement of the die 1 of the first embodiment.

That is, in the die 2 according to the first embodiment, it is possible to exert a very high usefulness when the extrusion conditions are not very severe. On the other hand, when the extrusion conditions are used in the case where the extrusion conditions are very harsh, the extrusion is performed after extrusion. As shown in FIGS. 13A and 13B in the die, at the longitudinal outer end of the retaining hole 21, both walls 20a and 20a of the bridge portion 20 are extruded by the extruded material being extruded. It is rarely seen that the inner direction causes deformation in a curved shape.

It is configured such that the entire support pin 13 enters the inner side of the core holding hole 21 so that the outer end of the core 12 does not protrude out of the holding hole 21, which is also the outer end side of the core 12. And the gap between the inner circumferential surface of the outer end portion of the retaining hole 21.

The occurrence of such a situation occurs when the core 12 is pulled backward from the inside of the retaining hole 21 when the core 12 is replaced by friction or the like, and the walls 20a and 20a at which both ends of the support pin 13 are deformed. ), It becomes difficult to pull out the core 12 by interfering with), and this causes the problem of creating a case where the exchange of the core 12 cannot be performed smoothly.

It is the dice according to the second embodiment that solve this problem and allow other usefulness to be exhibited.

That is, in the die 2 of the present embodiment shown in FIGS. 3A to 7C, the lengths of the guide grooves 22 and 22 of the core holding hole 21 in the core holding mold 14, i.e., holding The depth position at which the supporting ends 23 and 23 are installed in the hole 21 is supported by the supporting ends 23 and 23, and the supporting pins 13 have the flat portion 17 side at the end 23. The support pin 13 is designed to protrude outward from the outer end opening portion of the retaining hole 21 in the state of being supported toward (23).

The depth position at which the support end 23 is installed is most preferably designed such that the support pin 13 can protrude outward from the outer end opening of the support hole 21. 13 may be designed to be disposed close to the position of the outer end opening of the retaining hole 21.

In addition, as shown in FIG. 4, the rear end surface of the bridge portion 20 is pushed inwardly to the inside of the mold 14 at the rear of the bridge portion 20 of the core holding mold 14. The arrangement space 26 is formed. In the rear end surface of the bridge portion 20, the fitting recesses 34 and 34 extend in the width direction of the bridge portion 20 at each of the two positions at which the openings of the support holes 21 are inserted. Installed.

Further, as shown in FIG. 3B, the front end portion of the bridge portion 20 is formed to have a thin shape so that back pressure surfaces 35 and 35 which receive back pressure of the extruded material are formed there. The back pressure surfaces 35 and 35 are preferably secured as broadly as possible. Thereby, the holding force by the bridge part 20 acts on the core 12 during extrusion, the support force by the support pin 13 can be made low, the diameter of the support pin 13 can be made small, and furthermore, There is an advantage that the width of the grooves 22 and 22 for the guide can be made small.

The lid member 25 is formed to have a shape and size corresponding to the arrangement space 26 provided on the rear end surface of the bridge portion 20 of the core holding mold 14.

Then, the rear end side is formed in the shape of a mountain, so that the compressed material can be smoothly classified into both material through holes 18 and 18 of the holding mold 14.

On the front of the lid member 25, as shown in FIG. 4, an outer end protrusion of the core 12 and a receiving recess 36 for accommodating the protrusion of the support pin 13 are provided at the center thereof. The fitting convex portions 37 and 37 are fitted to the fitting recesses 34 and 34 of the bridge portion 20 on both sides of the receiving recess 36, respectively. Formed. In addition, cutouts 38 and 38 are formed at both rear end portions of the lid member 25, and the ring 40 as shown in FIG. 3 is fitted therein.

The assembly of the male 4 is the same as that of the first embodiment. That is, the support pin 13 is first inserted into the support hole 16 of the core 12 in a penetrating state, and the core 12 is inserted into the holding hole 21 from the rear of the holding mold 14. While being inserted, both ends 16a and 16a of the support pin 16 are brought into contact with the support ends 23 and 23 in the retaining hole 21 at the flat portion 17.

In the support state of the core 12, the support pin 13 protrudes outward from the retaining hole 21 of the bridge portion 20 as shown in FIG. Accordingly, the outer end of the core 12 also protrudes outward of the holding hole 21.

In this state, the lid member 25 is disposed in the placement space 26 of the rear portion of the bridge portion 20, and the rear end projection of the core 12 and the support pin 13 are placed in the recess 36 for accommodation. At the same time as accommodating the rear projections, the fitting projections 37 and 37 and the fitting recesses 34 and 34 are recessed and fitted. This fitting state is as shown to FIG. 7A-FIG. 7C. By the above, it is assembled to the male die 4.

Further, the female mold 3 is divided into a bearing tip 41 and a bearing tip holding mold 42, as shown in FIGS. 3A, 3B and 4. The holding die 42 is divided into a welding chamber forming die 44 and an accommodating die 45, as well as controlling the flow rate of the backup die 43 and the extruded material.

The die 2 is constituted by combining the male molds 3 and 4 with each other, and in the combined state, the tube member 1 is disposed between the tip molding part 15 of the core 12 and the female mold hole 5. The continuous slit 29 corresponding to the cross sectional shape of () is formed. In addition, the ring 40 is fitted to the rear portion of the combination die 2, a molten metal of an extruded material such as aluminum is poured into the die 2, and the extruded material is pressed into the extruder. In front of the die 2, the porous flat tube member 1 is extruded.

In the extrusion die 2 according to the second embodiment, the advantages of the die 2 according to the first embodiment are provided as it is, and the following advantages are provided thereon.

That is, in the male pin 4 of the pin support type as described above, as shown in FIG. 6 in the state in which the core 12 is supported by the support pin 13 in the retaining hole 21 of the bridge portion 20. As shown in FIG. 5, the supporting pin 13 protrudes outward of the holding hole 21, so that both ends of the supporting pin 13 are formed at the outer end of the holding hole 21. (20) The relatively thin walls 20a and 20a on both sides can be supported from the inside direction, so that the support pins can be supported even if the pressure of the extruded material acts on the outer surface of the walls 20a and 20a during extrusion. Both ends of (13) support the walls 20a and 20a from the inside direction, whereby the deformation of the walls 20a and 20a is actively prevented. Therefore, it is difficult to pull out the core 12 by causing the support pin 13 to hang on the walls 20a and 20a when the hollow molding part 15 is rubbed against the core 12 and replaced. This avoids the occurrence of an avalanche and can make the disassembly of the core 12 smooth and smooth.

In addition, fitting recesses 34 and 34 and fitting protrusions 37 and 37 are fitted to the rear end surface of the bridge portion 20 and the front surface of the lid member 25, and the recesses and protrusions thereof are provided. By the fitting, the lid member 25 is configured to be disposed on the rear end surface of the bridge portion 20, so that the core member 12 is bonded to the rear portion of the bridge portion 20 by welding to fix the core 12. ), The disassembly of the lid member 25 can be facilitated.

Furthermore, the fitting recesses 34 and 34 and the convex portions 37 and 37 are configured to be installed on the rear end surface of the bridge portion 20 and the front surface of the lid member 25 so as to extrude during extrusion. Even if an unstable pressure caused by the material acts on the lid member 25, it is regulated to cause an inadvertent deformation to the side in the longitudinal middle portion of the lid member 25, so that the displacement or dropping of the lid member 9 during extrusion is prevented. There is no worry.

In particular, in the engagement with the structure in which the mounting position of the support pin 17 is raised so that the rear end of the core 12 protrudes outward of the retaining hole 21, the lid member 25 and the bridge portion 20 are By the fitting combination by the uneven fitting structure between the mutually opposing surfaces such as, the deformation of the lid member 25 sideways in the longitudinal middle portion of the lid member 25 is strongly regulated during extrusion so that the lid member 25 has a core due to the deformation. Unintentional interference with the outer end of (12) is avoided, and damage and damage to the core 12 being extruded can be effectively prevented.

Third Embodiment

As shown in FIG. 10, the die according to the third embodiment is formed in the support 12 in the side of the core 12 by a support hole, and the support pin 31 is formed in the support recess 30. The insertion is arranged to hold the core 12 with the support pin 31.

[Example 4]

As shown in FIG. 11, the die according to the fourth embodiment has two support holes 16 and 16 formed in the core 12 and support pins (16) in each of the support holes 16 and 16. 13 and 13 are inserted to support the core 12 with these two support pins 13 and 13. In this way, the support state can be made very stable by using the two-point support structure. Moreover, you may comprise with the support structure more than two points.

It should be recognized that all the above-described examples are intended to specify preferred embodiments of the present invention. Therefore, the present invention is not limited to this, and any other design change is allowed within the spirit and scope of the present invention. For example, in the case of the support piece, as long as the core can be supported and held in the holding hole of the holding mold, the shape, the structure, the number, and the like are not limited to the above embodiments, but appropriate design changes can be made.

As described above, the combination die of the present invention uses a support piece such as a support pin, and the support piece supports and holds the core in the holding hole of the holding mold, and the core may be processed only by the support hole or the support recess. As a result, the core can be easily machined, and the male part of the split type can be easily manufactured, and further, the die can be easily manufactured, and the die can be advantageously manufactured in terms of cost.

In addition, since the support piece is supported at the end of the retaining hole of the retaining mold and the core is supported by the support piece, an accurate relative positional relationship between the retaining mold and the core in the extrusion direction is achieved with high precision and the like. It can be easily set even without processing, further reducing the production cost of the die and the die.

In addition, since the core is supported by the support piece and supported by the holding mold, the stress concentration on the core being extruded can be easily reduced, and the shape of the bearing can be provided with high reliability.

Therefore, the number of times of exchange by causing damage to the core during extrusion can be greatly reduced, and stable extrusion can be continued for a long time.

In addition, since the extrusion method according to the present invention is to be extruded using the above-described extrusion dice, it is possible to advantageously extrude the extruded material in terms of cost.

Claims (4)

In a combination die for extrusion comprising a combination of a female shape for forming a hollow material outer periphery and a male shape for forming a hollow material hollow part, the male shape has a hollow molded part at the tip and a support hole or support recess part at a side part thereof. And a core holding mold having a support piece inserted into the support hole or the support recess of the core in an outwardly protruding state, and a core holding hole having a support end facing the rear side in the extrusion direction. The combination for extrusion processing, characterized in that the insert is placed in the retaining hole of the mold while supporting the outward protrusion of the core support piece inserted into the support hole or the support recess portion at the support end of the retaining mold retaining hole. Dice. The combination die for extrusion processing according to claim 1, wherein the support piece protrudes outward from the opening position of the core holding hole or is disposed close to the opening position. 3. A core according to claim 1 or 2, wherein the core holding hole is formed with respect to the bridge portion crossing the material conduction hole of the core holding mold, and has a rear end surface of the bridge portion and a lid member disposed at the rear portion of the bridge portion. A combination die for extrusion processing, characterized in that irregularities are fitted to the front end face, and the lid member is fixed to the rear portion of the bridge portion by fitting the concave portion and the convex portion. In the combination die for extruded combination consisting of a male shape for forming the outer peripheral portion of the hollow material and a male shape for forming the hollow material hollow portion, the male shape has a hollow molded portion at the front end and a support hole or support recess is formed at the side surface. And a core holding mold having a core, a support piece inserted into the support hole or the support recess of the core in an outwardly protruding state, and a core holding hole having a support end facing the rear side in the extrusion direction. The core is extruded using a combination die inserted into the holding hole of the mold in a state where the outer projection of the core support piece inserted into the supporting hole or the supporting recess is supported at the supporting end of the holding mold holding hole. Extrusion process, characterized in that.