JP2017013117A - Molding die, molding method and molding product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molding die, a molding method and a molding product in which a gas exhausting amount can be drastically raised, and at the same time, working efficiency can be maintained.SOLUTION: Provided is a molding die 3 which comprises a fixing side insert 13 and a movable side insert 14 that can reciprocate against the fixing side insert 13, and molds a die-casting molding product in a cavity 2 constituted by both inserts 13, 14. Included are a first vent 24 in which a vent part 23 provided for exhausting gas outside is constituted in a gap space communicating directly with the cavity 2 and extending planarwise and a second vent 25 which is constituted in a gap space continuing to the first vent 24 at the exhaust tip side and is formed as broad so that gas ventilation resistance becomes smaller than the first vent 24.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a mold for light metal casting such as aluminum and a molding mold used for molding a resin, and a molding method and a molded product using the molding mold, and in particular, exists in a mold space such as a runner and a cavity. The present invention relates to a molding die that can quickly discharge gas to the outside, a molding method, and a molded product obtained thereby.

  For example, in casting by die casting, gas such as air and water vapor existing in a mold enters the cavity by molten metal pushed by a plunger. It is known that defects such as a nest of a die-cast molded product can be reduced by forming the cavity gas as much as possible to the outside. As a technique for reducing defects in a die-cast product, a vacuum injection molding method in which die casting is performed in a state where a cavity is decompressed is widely used.

  In the vacuum injection molding method, there is a problem that equipment and maintenance for increasing the degree of vacuum of the cavity are required and the cost increases. As a method not using the vacuum injection molding method, a vent part for discharging gas to the molding die has been provided. FIG. 14A is a schematic cross-sectional view of a general molding die 100. In this molding die 100, molten metal passes through a runner 101 and a gate 102 and is filled into a cavity 105 constituted by a fixed die 103 and a movable die 104. At that time, the gas existing in the cavity 105 and the like passes through the overflow portion 106 and is discharged to the outside of the mold.

  The overflow part 106 is provided with a vent part 107 through which gas is discharged to the outside of the mold. As shown in FIG. 14B, the vent portion 107 is usually provided with a gap of about 0.5 mm on the opposite side of the overflow portion 106 from the cavity 105, and the gap gradually becomes about 0.1 mm as the distance from the cavity 105 increases. It has a shape that can be narrowed to By setting it as such a vent part 107, gas is discharged | emitted and a molten metal shall not be blown off by casting pressure.

  However, since the conventional vent part 107 becomes narrow as it leaves | separates from the cavity 105, the exhaust_gas | exhaustion resistance of gas is large. Further, the molten metal enters the vent portion 107 and solidifies, thereby inhibiting gas discharge. For this reason, it cannot be said that the gas is exhausted sufficiently by the conventional vent portion 107, and accordingly, it is difficult to further improve the quality of the die cast product.

  In Patent Document 1, a wedge-shaped notch that narrows toward the rear is provided at the tip of an extrusion pin for extruding a molded product formed in a cavity, and gas is discharged by providing a groove behind the notch. An extrusion pin is described. Patent Document 2 describes a method of discharging gas by providing a similar notch at the tip of an extrusion pin that pushes out a runner connected to a cavity. As disclosed in Patent Document 3, a method of discharging gas by a chill vent provided in a cavity is also known.

Japanese Patent No. 4085182 Japanese Patent No. 5431780 JP 2003-132656 A

  When the method of Patent Document 2 was used for aluminum casting by die casting, and gas was discharged by a runner in front of the cavity, a better die cast product was obtained than when gas was discharged at a conventional vent part. However, the amount of gas discharged by this method is not sufficient, and it is difficult to obtain a high-quality die-cast product. Even with the method using the chill vent of Patent Document 3, the amount of gas discharge cannot be dramatically improved, and the quality of the die-cast molded product is also accompanied by this. Furthermore, in the gas discharge method of Patent Document 2, as shown in FIG. 15, the wedge-shaped traces at the end of the extrusion pin remain in the runner in a sharp shape, and there is a risk of damaging the hand during the runner excision work, There has been a problem of lowering work efficiency.

  Accordingly, in view of the problems of the prior art, the present invention provides a molding die, a molding method, and a molded product that can dramatically improve the amount of gas discharged and maintain work efficiency. With the goal.

  The molding die of the present invention comprises a fixed mold and a movable mold that can be moved forward and backward with respect to the fixed mold, and a molten material is filled into the cavity constituted by the fixed mold and the movable mold through an introduction path. A molding die for molding a molded product, wherein a vent part for discharging gas is provided in a mold space constituted by the cavity and the introduction path, and the vent part is formed by the mold. A first vent formed by a gap space extending in a planar shape that directly communicates with the space, and the first vent is continuous on the exhaust tip side, and is wide so that the gas ventilation resistance is smaller than that of the first vent. And a second vent formed.

  According to the present invention, the vent portion for discharging the gas is configured as a first vent formed by a gap space that directly communicates with the mold space, and the first vent is continuous with the first vent on the exhaust tip side. And a second vent that is widely formed so as to reduce the gas ventilation resistance. Unlike the conventional one provided in the overflow portion, the vent portion is a space in which the first vent directly communicating with the mold space is thin, and the second vent that follows is wider than the first vent. Yes. In this vent section, the first vent that once narrows the gas discharge path increases the gas discharge speed, and the second vent that is wider than the first vent passes through the first vent. After that, the gas ventilation resistance is reduced. Thereby, the discharge amount of gas can be improved dramatically. Further, the molded product has no sharp deformed portion, and the hand is not damaged during post-processing. Thereby, work efficiency can be maintained.

  It is preferable that the clearance gap of the said 1st vent is 0.05-0.30 mm. By setting the gap interval of the first vent to 0.05 to 0.30 mm, the gas discharge speed can be improved.

  The length of the first vent in the exhaust direction is preferably 3 to 30 mm. By setting the length of the first vent in the exhaust direction to 3 to 30 mm, appropriate ventilation resistance can be obtained, and blowing of molten metal can be prevented.

  For example, the second vent may be formed of a gap space that extends in the same direction as the first vent, and the gap interval of the gap space may be 0.35 to 2.00 mm. By setting the gap interval of the second vent formed by the gap space extending in the same direction as the first vent to 0.35 to 2.00 mm, the gas ventilation resistance after passing through the first vent is effectively reduced. It can reduce and it can prevent blowing out of a molten metal with it.

  You may form the said 2nd vent comprised by the clearance gap extended in the same direction as the said 1st vent with the width | variety larger than the said 1st vent. If the second vent is formed with a width larger than that of the first vent, the gas ventilation resistance after passing through the first vent can be greatly reduced, and the gas discharge speed can be further improved.

  You may comprise the said 2nd vent in the cylindrical space which goes to a different direction from the said 1st vent, for example. For example, it may be difficult to extend the second vent in the same direction as the first vent in a fixed mold and a sliding mold having a plurality of movable molds. In such a case, if the second vent is configured with a cylindrical space that is directed in a different direction from the first vent, the vent portion can be easily configured.

  A part or all of the part constituting the vent part may be detachable from the molding die. In this case, part or all of the parts constituting the vent part can be replaced, and the maintainability can be improved.

  A part or all of the part constituting the vent part, which is made into a part, may be made of a material different from the mold part provided with the vent part. Depending on the molten material, it may adhere to the mold, and if part or all of the parts that make up the vent part are made of different materials, the adhesion of such molten material can be reduced. Can do.

  At the time of molding, for example, the molten metal is solidified not only in the cavity but also in a runner that is an introduction path for introducing the molten material to the cavity and an overflow portion that accumulates the molten material overflowing from the cavity. The molded product released from the molding die includes a product part molded in the cavity and a non-product part molded in the runner and the overflow part. Therefore, after molding, it is necessary to excise non-product parts from the molded product. In the present invention, since there is no overflow portion for allowing the molten material to flow around the cavity, the portion to be cut off after molding can be reduced, and the necessary amount of metal or resin can be greatly reduced. Thereby, working efficiency can be improved and the cost can be reduced.

  The molding method according to the present invention is a molding method in which molding is performed using the molding die according to the present invention, wherein the first vent is used to increase a gas discharge rate, and the second vent is used to form the first vent. The gas ventilation resistance after passing through is reduced.

  The molding die used in the molding method of the present invention includes a first vent in which a vent portion for discharging gas is configured as a gap space that directly communicates with the mold space, and an exhaust tip side on the first vent. And a second vent that is widely formed so that the gas ventilation resistance is smaller than that of the first vent. Unlike the conventional one provided in the overflow portion, the vent portion is a space in which the first vent directly communicating with the mold space is thin, and the second vent that follows is wider than the first vent. Yes. In this vent section, the first vent 24 that once narrows the gas discharge path increases the gas discharge speed, and the second vent that is wider than the first vent is connected to the first vent. The gas ventilation resistance after passing through is reduced. Thereby, the discharge amount of gas can be improved dramatically. Further, the molded product has no sharp deformed portion, and the hand is not damaged during post-processing. Thereby, work efficiency can be maintained.

  The molded product of the present invention is a molded product that is molded by filling a cavity constituted by a molding die with a molten material, and that the molding die is the molding die of the present invention. It is a feature.

  When the molding die of the present invention is used, the amount of gas discharged is remarkably improved, so that a molded product with extremely high quality can be obtained. Further, the molded product does not have a sharp deformed portion, and the hand is not damaged during post-processing work, so that work efficiency can be maintained.

  According to the present invention, since the gas discharge speed is increased by the first vent and the gas ventilation resistance after passing the first vent is reduced by the second vent, the gas discharge rate is greatly increased. Can be improved. Since the molded product does not have a sharp deformed portion and does not damage the hand during the post-processing operation, the work efficiency can be maintained.

It is a schematic cross section of a die casting apparatus provided with the metal mold | die concerning 1st Embodiment of this invention. It is sectional drawing of the metal mold | die which has the metal mold | die for shaping | molding which concerns on 1st Embodiment of this invention. It is a front view of the state in which the movable side nest is inserted in the movable main mold. It is sectional drawing of the vent part of a metal mold | die, and its periphery. It is a cross-sectional perspective view of the vent part of a metal mold | die, and its periphery. It is a top view of the molded product at the time of mold release. It is the top view and sectional drawing of the vent part of the metal mold | die concerning 2nd Embodiment of this invention. (A) is sectional drawing of the vent part and its periphery of the metal mold | die concerning 3rd Embodiment of this invention, (b) is a perspective view of vent components. It is sectional drawing of the metal mold | die concerning 4th Embodiment of this invention, and a side view of the molded article shape | molded with this metal mold | die for molding. It is a top view of the state which combined the 1st-4th slide type | mold in the metal mold | die of 4th Embodiment. It is sectional drawing of the vent part of a metal mold | die, and its periphery. It is a perspective view of the vent part of the metal mold | die for shaping | molding. (A) is a photograph of a molded product molded with a molding die according to the fourth embodiment of the present invention, and (b) is a photograph of a molded product molded with a conventional molding die. (A) is a schematic cross-sectional view of a conventional molding die, and (b) is a schematic cross-sectional view of an overflow portion and its periphery. It is a principal part photograph of the conventional die-cast molded product shape | molded using the extrusion pin which comprises a vent part.

  An embodiment of the present invention will be described by taking die casting as an example. FIG. 1 is a schematic cross-sectional view of a die casting apparatus 1 including a molding die 3 according to an embodiment of the present invention. This die casting apparatus 1 is a casting apparatus for obtaining a die cast product (molded product), and a mold 4 having a molding die 3 constituting the cavity 2 and a molten metal as a molten material are added to the cavity 2. A pressurizing mechanism 5 for filling in a pressurized state and a material supply unit 7 for supplying molten metal to a supply path 6 between the molding die 3 and the pressurizing mechanism 5 are provided.

  The pressurizing mechanism 5 includes a molten metal reservoir, a hydraulic cylinder 8, a plunger 9 introduced into the hydraulic cylinder 8, and the like. The molten metal introduced into the supply path 6 between the molding die 3 and the pressurizing mechanism 5 is filled into the cavity 2 by the pressure of the plunger 9. The mold 4 includes a main mold 10 and a molding mold 3 fitted in the main mold 10. The main mold 10 includes a fixed main mold 11 and a movable main mold 12. The fixed main mold 11 is fitted with a fixed side insert 13 (fixed mold), and the movable main mold 12 has a movable side insert 14 (movable). Type) is fitted.

  The molding die 3 includes a fixed side insert 13 and a movable side insert 14 that can be moved forward and backward with respect to the fixed side insert 13 and can be changed between a mold closed state and a mold open state. . The fixed side insert 13 and the movable side insert 14 constitute the cavity 2, and the molding die 3 is configured with a gate, a runner, and the like as an introduction path serving as a runner. The introduction path referred to in the present invention refers to a flow path such as a runner or a sprue for guiding a molten material such as molten metal to the cavity 2. A mold space is formed by the cavity 2 and the introduction path.

  After the mold 4 is closed, molten aluminum (hereinafter referred to as molten metal) is poured into the supply path 6 from the material supply unit 7, the plunger 9 of the pressurizing mechanism 5 moves forward, and the molten metal in the supply path 6 becomes the molding metal. It is transferred to the mold 3. The molten metal flows into the cavity 2 through a runner, a gate, etc. and is filled. Thereafter, the molten metal is solidified in the cavity 2 to form a molded product. The die casting apparatus 1 has mold release means such as an extrusion pin 15 for taking out a molded product from the molding die 3, and after the mold 4 is opened, the solidified molded product is an extrusion pin. 15 is released from the molding die 3.

  FIG. 2 is a cross-sectional view of a mold 4 having a molding die 3 according to an embodiment of the present invention, and FIG. 3 is a front view of a state in which a movable side insert 14 is fitted in the movable main mold 12. . As shown in FIG. 2, a vent portion 23 that discharges gas is provided in the cavity 2 that is a mold space. As shown in FIG. 3, the movable side insert 14 is formed with a molded part 18 that becomes the cavity 2, a gate mold part 19 that becomes the gate 26 below the molded part 18, a runner mold part 20 that becomes the runner 27, and the like. ing. In FIG. 3, three vent mold parts 22 are formed on the upper part of the molded part 18 of the movable side insert 14. The vent mold part 22 is formed by an extremely shallow groove and becomes a part of the vent part 23 that discharges the gas in the cavity 2 to the outside of the mold 4.

  In the mold closed state, the movable side insert 14 abuts on the fixed side insert 13, and the vent type portion 22 of the movable side insert 14 is combined with the flat contact surface 21 of the fixed side insert 13 to form the vent portion 23. The As described above, the vent portion 23 of the present embodiment is configured by the mating surface of the fixed side insert 13 and the movable side insert 14. There is no conventional overflow portion around the cavity 2 of the molding die 3, and there is no space for the molten metal in the cavity 2 to flow out and be stored.

  FIG. 4 is an enlarged cross-sectional view of the vent portion 23, and FIG. 5 is an enlarged cross-sectional perspective view of the vent portion 23. The vent portion 23 serves as a flow path for discharging the gas in the cavity 2 to the outside, and includes a first vent 24 configured by a gap space directly communicating with the cavity 2, and an exhaust tip at the first vent 24. And a second vent 25 which is wide and formed so as to be continuous on the side and have a lower gas flow resistance than the first vent 24. Widely formed means that the cross-sectional area in the flow path direction (the cross-sectional area perpendicular to the left-right direction in FIG. 4) is increased. That is, the second vent 25 is larger in cross-sectional area in the flow path direction than the first vent 24.

  The first vent 24 is configured by a gap space that extends in a planar shape in the penetration direction (mold edge direction) in FIG. 4 and the right direction (flow path direction) in FIG. 4. The second vent 25 is configured by a gap space that extends in a plane in the same direction as the first vent 24. The first vent 24 and the second vent 25 have the same width d in the through direction in FIG. 4, and the second vent 25 is configured to be longer than the first vent 24 in the flow path direction. This vent portion 23 is provided directly in the cavity 2, unlike the conventional one provided in the overflow portion. The main mold 10 on the exhaust tip side of the vent portion 23 has a wider gas flow path.

  Gases such as air existing in the runner and the cavity 2 are discharged to the outside of the mold 4 through the vent portion 23 and the gas flow path ahead. Although the molten metal filled in the cavity 2 slightly flows into the vent portion 23, it is solidified in the vicinity of the inlet 24 a of the first vent 24 and does not enter deep into the gap space of the first vent 24.

  Both the first vent 24 and the second vent 25 are formed in a rectangular shape in a cross-sectional view in the penetrating direction in FIG. 4, and the exhaust tip of the first vent 24 is connected from the inlet 24 a of the first vent 24 directly communicating with the cavity 2. Up to the end 24b on the side is formed in the same cross-sectional shape. The end portion 24 b of the first vent 24 has a stepped shape downward in FIG. 4, and the end portion 24 b of the first vent 24 serves as the inlet 25 a of the second vent 25. By configuring the vent portion 23 with the first vent 24 having a thin gap space and the second vent 25 having a gap space wider than the first vent 24, the following action can be obtained.

  When the molten metal flows into the cavity 2, the vicinity of the inlet 24 a of the first vent 24 configured by a narrow gap space is reduced to a vacuum state, and the discharge speed of the gas existing in the cavity 2 increases. Since the second vent 25 ahead is wider than the first vent 24, the gas ventilation resistance after passing through the first vent 24 can be reduced. That is, a molding method can be performed in which the first vent 24 increases the gas discharge speed of the cavity 2 and the second vent 25 reduces the gas ventilation resistance after passing through the first vent 24. By performing this molding method, the amount of gas discharged can be dramatically improved.

  The gap interval t1 of the first vent 24 is preferably 0.05 to 0.30 mm, more preferably 0.07 to 0.20 mm, and still more preferably 0.10 to 0.15 mm. If the gap interval t1 of the first vent 24 is smaller than 0.05 mm, the gas ventilation resistance becomes too large, and the gas discharge speed is lowered. If the gap interval t1 of the first vent 24 is larger than 0.30 mm, the gas is easily discharged, but the molten metal enters the first vent 24 and solidifies, so that the gas flow path is interrupted on the way.

  The length n1 of the first vent 24 in the exhaust direction (flow channel direction) is preferably 3 to 30 mm, and more preferably 5 to 20 mm. If the length n1 of the first vent 24 in the exhaust direction is shorter than 3 mm, the ventilation resistance is too small and the molten metal in the cavity 2 may blow out. If the length n1 of the first vent 24 in the exhaust direction is longer than 30 mm, the ventilation is performed. Resistance increases and gas discharge rate decreases. That is, (t1 / n1) = 0.016 to 0.1 with respect to the clearance t1 of the first vent 24 and the length n1 of the first vent 24 in the exhaust direction (flow path direction).

  The gap interval t2 of the second vent 25 is preferably 0.35 to 2.00 mm, and more preferably 0.45 to 1.50 mm. If the gap interval t2 of the second vent 25 is smaller than 0.35 mm, the ventilation resistance becomes too large and the gas discharge speed decreases, and if the gap interval t2 of the second vent 25 is larger than 2.00 mm, the ventilation resistance. May become too small and the molten metal in the cavity 2 may blow out. The length n2 of the second vent 25 in the exhaust direction does not greatly affect the gas discharge speed. For example, the second vent 25 is extended to the outer end of the molding die 3. The gas flow path in the main mold 10 further beyond the end of the second vent 25 may be a wider flow path than the second vent 25.

  The width d of the first vent 24 and the second vent 25 in the penetrating direction in FIG. 4 is appropriately set depending on the number of the vent portions 23 provided in the cavity 2 that is the mold space, the size, shape, and molding conditions of the cavity 2. . In the present embodiment, the width d of the second vent 25 in the penetration direction in FIG. 4 is the same as that of the first vent 24. The width d of the second vent 25 in the penetrating direction in FIG. 4 may be larger than that of the first vent 24. If the second vent 25 is formed with a width d larger than that of the first vent 24, the gas ventilation resistance after passing through the first vent 24 can be greatly reduced, and the gas discharge speed can be further improved.

  By setting the dimensions of the respective parts of the first vent 24 and the second vent 25 within the above ranges, the gas in the cavity 2 can be efficiently discharged while preventing the molten metal from being blown out. In addition, when the gas flow path configured on the exhaust tip side of the second vent 25 is configured as a gap space, the gap interval is preferably 5.0 to 20 mm. By setting the gap interval of the gas flow path configured on the exhaust tip side of the second vent 25 to 5.0 to 20 mm, the gas that has passed through the second vent 25 can be quickly discharged to the outside. it can.

  In the molding die 3 of this embodiment and the molding method using this molding die 3, the vent portion 23 that discharges the gas in the cavity 2 is a gap space that directly communicates with the cavity 2 that is the mold space. The first vent 24 is configured, and a second vent 25 that is continuous with the first vent 24 on the exhaust tip side and is formed so as to have a lower gas flow resistance than the first vent 24. ing. Unlike the conventional one provided in the overflow portion, the vent portion 23 is a space in which the first vent that communicates directly with the mold space is thin, and the subsequent second vent is wider than the first vent. ing.

  In the vent portion 23, the first vent 24 that once narrows the gas discharge path increases the gas discharge speed, and the second vent 25 that is wider than the first vent 24 is the first vent 24. The ventilation resistance of the gas after passing through the vent 24 is reduced. Thereby, the discharge amount of gas can be improved dramatically. Further, the molded product has no sharp deformed portion, and the hand is not damaged during post-processing. Thereby, work efficiency can be maintained. By using the molding die 3 of the present embodiment, a high-quality die cast product with extremely few defects such as a nest can be obtained.

  By setting the gap interval t1 of the first vent 24 to 0.05 to 0.30 mm, the gas discharge speed can be improved. By setting the length n1 of the first vent 24 in the exhaust direction to 3 to 30 mm, appropriate ventilation resistance can be obtained, and blowing out of the molten metal can be prevented. By setting the gap interval t2 of the second vent 25 to 0.35 to 2.00 mm, the gas ventilation resistance after passing through the first vent 24 is effectively reduced, and at the same time, the blowout of the molten metal is prevented. Can do.

  Conventionally, at the time of molding, the molten metal is solidified not only in the cavity, but also in a runner for guiding the molten metal to the cavity and an overflow part that accumulates the molten metal overflowing from the cavity. The molded product released from the mold includes a product part molded in the cavity and a non-product part molded in the runner and the overflow part. Therefore, after molding, it is necessary to excise non-product parts from the molded product.

  In the present embodiment, there is no overflow part for allowing the molten metal to flow out around the cavity 2, so that, for example, a molded product 30 with few non-product parts as shown in FIG. Processing work can be reduced. In this molded product 30, only the runner molded part 32 and the burr 33 which are non-product parts exist around the die-cast molded product 31 as the product part. Furthermore, the required amount of metal can be greatly reduced. Thereby, working efficiency can be improved and the cost can be reduced. In addition, the post-processed die-cast molded product does not leave a mark after the overflow portion is cut off, and a very good appearance can be obtained.

  As an example, aluminum was molded by the molding die 3 of the above embodiment to obtain a die cast product. As a comparative example, aluminum was molded by a conventional molding die provided with an overflow portion without providing the vent portion of the above embodiment, and a die cast product was obtained. Each die-cast molded product of Example and Comparative Example was cut, and the cross section was visually observed. There were no defects such as a nest in the die-cast molded product of the example, and the die-cast molded product of the comparative example contained several nests.

  FIG. 7 is a plan view and a cross-sectional view of the vent portion 50 of the molding die according to the second embodiment of the present invention. In this embodiment, the vent part 50 which discharges | emits gas is provided in the runner 51 which is a metal mold | die space. The end portion 52b of the first vent 52 is curved toward the runner 51 side in plan view. The end portion of the first vent may be curved toward the side opposite to the runner 51 in plan view. The end portion of the first vent may be wavy in plan view. As described above, the end portion 52b of the first vent 52 may be formed in various shapes.

  FIG. 8A is a sectional view of the vent portion 41 and its periphery of the molding die 40 according to the third embodiment of the present invention, and FIG. 8B is a perspective view of the vent component 42. The runner 43, which is a mold space, is provided with a vent portion 41 for discharging gas. In the present embodiment, a stepped vent part 42 shown in FIG. 4B is manufactured separately, so that a part of the vent part 41 is made into a part and is detachably incorporated in the space 44 communicating with the runner 43. It is out. This space 44 is formed by forming a vent groove 41a in one mold having a runner groove 43a constituting the runner 43 and combining the other mold. As a result, a part of the vent portion 41 is made into a part and is detachable from the molding die 40.

  The vent part 42 may be made of the same material as the mold part 45 provided with the vent part 41 or may be made of a different material. When the vent part 42 is made of a different material, a material that is difficult to adhere, for example, aluminum that is a molten material may be used. In the present embodiment, the gap interval t1 of the first vent 24 is 0.1 mm, the gap interval t2 of the second vent 25 is 0.5 mm, the exhaust direction length n1 of the first vent 24 is 20 mm, and the second vent The length n2 in the exhaust direction of 25 is 50 mm, and the gap interval of the gap space provided at the tip of the second vent 25 (right side in FIG. 5A) is 5 mm. The width of the first and second vents 24 and 25 (the width in the through direction in FIG. 8A) is 20 mm. That is, the vent part 42 is a stepped molded product having a longitudinal length of 70 mm and a width of 20 mm.

  Even in this case, the same effect as the above embodiment can be obtained. That is, the vent part 41 for discharging the gas is continuous with the first vent 24 formed in a gap space directly communicating with the runner 43 which is a mold space, and the first vent 24 on the exhaust tip side and the first vent 24. It has the 2nd vent 25 formed widely so that the ventilation resistance of gas may become smaller than the 1 vent 24. FIG. The vent portion 41 is a space where the first vent 24 directly communicating with the runner 43 is thin, and the second vent 25 following the first vent 24 is wider than the first vent 24.

  In the vent portion 41, the first vent 24 that once narrows the gas discharge path increases the gas discharge speed, and the second vent 25 that is wider than the first vent 24 is the first vent 24. The ventilation resistance of the gas after passing through the vent 24 is reduced. Thereby, the discharge amount of gas can be improved dramatically. The molded product has no sharp profile and does not damage the hand during post-processing operations. Thereby, work efficiency can be maintained.

  As a modified example of the vent part 42 shown in FIG. 8 (b), two rectangular parallelepiped parts are manufactured without being stepped, and are stacked in a detachable manner in the molding die 40. Or may be fixed. All of the parts constituting the vent part may be made into parts, and this may be removably incorporated into the molding die or fixed.

  If a part or all of the parts constituting the vent portion 41 are made detachable from the molding die 40 by incorporating the bent parts into the molding die 40, the vent portion 41 is configured. It is possible to replace part or all of the parts to be performed, and to improve maintenance. For example, the vent part may be made of the same material as the mold part provided with the vent part or a different material, and the vent part may be replaced as appropriate in view of the degree of adhesion of the molten material.

  If a bent part made of a material such as ceramic, which is a material to which the molten material is difficult to adhere, is manufactured and incorporated into a molding die, adhesion of the molten material to the molding die can be reduced. . The surface of the bent part may be modified to make it difficult to adhere the molten material. Specifically, the surface of the vent part may be coated with Cr plating, carbon, various sprayed coatings, or the like, and a minute unevenness may be provided on the surface of the vent part to make it difficult to adhere the molten material.

  FIG. 9 is a cross-sectional view of a molding die 60 according to a fourth embodiment of the present invention, and a side view of a molded product 61 molded by the molding die 60. FIG. 10 is a molding die of the same embodiment. FIG. 6 is a plan view of the mold 60 in a state where the first to fourth slide molds 62 to 65 that are movable molds are combined. FIG. 9 shows a cross-sectional portion taken along line AA in FIG. The molding die 60 of the present embodiment is of a slide type that molds a molded product 61 having an undercut portion.

  The molding die 60 includes a movable mold 77 and a fixed mold (not shown). The movable mold 77 includes the first to fourth slide molds 62 to 65 shown in FIG. 10 and the first to fourth slide molds. It is comprised with the 5th movable mold | type 70 of FIG. 9 contact | abutted to the end surface 71 in 62-65 type | mold closed states.

  Three vent portions 67 for discharging gas are provided in a cavity 66 that is a mold space. Each of the vent portions 67 includes a first vent 68 configured by a gap space extending in a planar shape that directly communicates with the cavity 66, and continues to the first vent 68 on the exhaust tip side, and is more than the first vent 68. It has a cylindrical second vent 69 that is widely formed so as to reduce the gas ventilation resistance. There is no conventional overflow portion around the cavity 66 of the molding die 60, and no space is provided for allowing the molten metal in the cavity 66 to flow out and accumulate.

  As shown in FIG. 10, the first to fourth slide molds 62 to 65 are formed with a molded product portion 72 that becomes the cavity 66. Vent mold portions 73 are formed on the outer sides of the molded product portions 72 of the first, second, and fourth slide dies 62, 63, and 65, respectively. The vent mold part 73 is formed of an extremely shallow groove and becomes a part of the vent part 67 that discharges the gas in the cavity 66 to the outside of the mold.

  In this embodiment, the vent part 67 is formed by forming the first vent 68 on the mating surface of two movable molds among the movable molds divided into a plurality, and forming the second vent 69 by cutting out the other movable molds. Yes. Specifically, the first first vent 68 is configured by a mating surface of the first slide mold 62 and the fifth movable mold 70, and the second vent 69 communicating with the first vent 68 is configured as the fifth movable. The mold 70 is hollowed out. The second first vent 68 is constituted by a mating surface of the second slide mold 63 and the fifth movable mold 70, and the second vent 69 communicating with the first vent 68 is cut through the fifth movable mold 70. Is configured. The third first vent 68 is constituted by the mating surface of the fourth slide mold 65 and the fifth movable mold 70, and the second vent 69 communicating with the first vent 68 is cut through the fifth movable mold 70. Are configured.

  After the molded product 61 is molded in the cavity 66, the first to fourth slide molds 62 to 65 shown in FIG. 10 move outward, and then the fifth movable mold 70 shown in FIG. The product 61 is pushed by an extrusion pin and released.

  FIG. 11 is a cross-sectional view of the vent portion 67 and its periphery of the molding die 60, and FIG. 12 is a perspective view of the vent portion 67. The first vent 68 is configured by a gap space 74 that extends in a planar shape, and the second vent 69 is configured by a cylindrical cylindrical space 75 that extends in a different direction from the first vent 68. The second vent 69 of the present embodiment extends in a direction orthogonal to the first vent 68. When the second vent 69 is configured in a different direction from the first vent 68, the angle of the second vent 69 with respect to the first vent 68 is not limited.

  The main mold (not shown) on the exhaust tip side of the vent portion 67 has a wider gas flow path. Gases such as air existing in the runner and the cavity 66 are discharged to the outside of the mold through the vent portion 67 and the gas flow path ahead. Although the molten metal filled in the cavity 66 slightly flows into the vent portion 67, it is solidified in the vicinity of the inlet 68 a of the first vent 68 and does not enter deep into the gap space 74 of the first vent 68.

  The gap space 74 formed by the vent mold portions 73 of the first, second, and fourth slide molds 62, 63, and 65 and the fifth movable mold 70 is formed in a rectangular shape in a horizontally long cross-sectional view. The gap space 74 includes a first vent 68 on the cavity 66 side and a base end portion 76 at the tip (upper side in FIG. 11). At the end 68 b of the first vent 68, the gas flow path is changed by 90 ° in the direction in which the second vent 69 extends. An end 68 b of the first vent 68 serves as an inlet 69 a of the second vent 69. By configuring the vent portion 67 with the first vent 68 composed of the thin gap space 74 and the second vent 69 of the cylindrical space 75 that is wider than the first vent 68, the same action as in the above embodiments can be obtained. Can do.

  The gap interval t1 of the first vent 68 is preferably 0.05 to 0.30 mm, more preferably 0.07 to 0.20 mm, and still more preferably 0.10 to 0.15 mm. When the gap interval t1 of the first vent 68 is smaller than 0.05 mm, the gas ventilation resistance becomes too large, and the gas discharge speed is lowered. If the gap interval t1 of the first vent 68 is larger than 0.30 mm, the gas is easily discharged, but the molten metal enters the first vent 68 and solidifies, thereby interrupting the gas flow path.

  The length n1 of the first vent 68 in the exhaust direction is preferably 3 to 30 mm, and more preferably 5 to 20 mm. If the length n1 of the first vent 68 in the exhaust direction is shorter than 3 mm, the ventilation resistance is too small and the molten metal in the cavity 66 may blow out. If the length n1 of the first vent 68 in the exhaust direction is longer than 30 mm, the ventilation is performed. Resistance increases and gas discharge rate decreases. The width of the first vent 68 in the penetrating direction in FIG. 11 is appropriately set depending on the number of vent portions 67 provided, the size, shape, and molding conditions of the cavity 66.

  The second vent 69 is formed with a size having a ventilation resistance that does not decrease the gas discharge speed and does not blow out the molten metal in the cavity 66. For example, in the present embodiment, the clearance t1 of the first vent 68 is 0.10 mm, whereas the diameter of the cross section of the cylindrical second vent 69 is 8.00 mm. The second vent 69 is not limited to a cylindrical shape, and may have any cross-sectional shape. The length of the second vent 69 in the exhaust direction does not significantly affect the gas discharge speed. For example, the second vent 69 extends to the outer end of the molding die 60. The gas flow path in the main mold further beyond the end of the second vent 69 may be a wider flow path than the second vent 69. By setting the dimensions of the respective parts of the first vent 68 and the second vent 69 within the above ranges, the gas in the cavity 66 can be efficiently discharged while preventing the molten metal from being blown out.

  In the molding die 60 of this embodiment and the molding method using this molding die 60, the vent portion 67 for discharging the gas in the cavity 66 communicates directly with the cavity 66, which is the die space, in the gap space 74. And a second vent 69 that is continuous with the first vent 68 on the exhaust tip side and that is wider than the first vent 68 and has a lower gas flow resistance. doing. Unlike the conventional one provided in the overflow portion, the vent portion 67 is a space in which the first vent 68 directly communicating with the mold space is thin, and the second vent 69 following the first vent 68 is more than the first vent 68. Is also getting wider.

  In the vent portion 67, the first vent 68 that once narrows the gas discharge path increases the gas discharge speed, and the second vent 69 that is wider than the first vent 68 is the first vent 68. The gas ventilation resistance after passing through the vent 68 is reduced. Thereby, the discharge amount of gas can be improved dramatically. The molded product 61 does not have a sharp deformed portion and does not damage the hand during post-processing. Thereby, work efficiency can be maintained. By using the molding die 60 of the present embodiment, it is possible to obtain a high-quality die-cast product with very few defects such as a nest.

  FIG. 13A is a photograph of a molded product molded with the molding die 60 according to the fourth embodiment of the present invention, and FIG. 13B is a photograph of a molded product molded with a conventional molding die. Conventionally, at the time of molding, the molten metal is solidified not only in the cavity, but also in a runner for guiding the molten metal to the cavity and an overflow part that accumulates the molten metal overflowing from the cavity. The molded product released from the mold includes a product part molded in the cavity and a non-product part molded in the runner and the overflow part. In the molded product shown in the photograph of FIG. 13 (b), there is a non-product portion molded at the overflow portion. Therefore, after molding, it is necessary to excise non-product parts from the molded product. In the present embodiment, since there is no overflow portion for allowing the molten metal to flow out around the cavity 66, the molded product shown in the photograph of FIG. 13A is obtained, and post-processing work for cutting away unnecessary portions is performed. Can be reduced. In this molded product, only a runner molded part and a burr which are non-product parts exist around the die-cast molded product as a product part. Furthermore, the required amount of metal can be greatly reduced. Thereby, working efficiency can be improved and the cost can be reduced. In addition, the post-processed die-cast molded product does not leave a mark after the overflow portion is cut off, and a very good appearance can be obtained.

  The present invention is not limited to the above embodiment. The above embodiment is an example of a molding die and a molding method according to the present invention. The molding die and molding method of the present invention can be applied not only to die casting for molding light metals such as aluminum, but also to resin injection molding for molding synthetic resins. The shape and number of fixed molds, movable molds, fixed side inserts and movable side inserts, the shape and number of main molds, the shape and number of cavities, runners, sprues, gates, the number of vents, the molds that provide vents It is not limited.

  The portion where the vent portion is provided may be any mold space as long as it is a cavity in which the molded product is molded and an introduction path through which the molten material passes. Other space may exist in the part which transfers from a 1st vent to a 2nd vent like the base end part of 4th Embodiment. The vent portion may be provided in both the cavity and the introduction path, or may be provided only in the cavity, only the runner that is the introduction path, or only in the other introduction path as in the above embodiment. The first and second vents of the vent part may be provided by punching out the molds, respectively, or may be provided by using the mating surfaces of a plurality of molds. In the first to third embodiments, a vent is formed by providing a groove in one of two molds, but venting is performed by providing a groove in both molds or a plurality of molds. You may comprise a part. When using the molding die of the present invention provided with a vent portion, the various members provided as necessary may be in any form as long as the effects of the present invention are not impaired.

DESCRIPTION OF SYMBOLS 1 Die casting apparatus 2 Cavity 3, 40 Mold for mold 4 Mold 5 Pressurization mechanism 6 Supply path 7 Material supply part 8 Hydraulic cylinder 9 Plunger 10 Main mold 11 Fixed main mold 12 Movable main mold 13 Fixed side nest 14 Moveable side Nest 15 Extrusion pin 18 Molded product part 19 Gate mold part 20 Runner mold part 21 Contact surface 22 Vent mold part 23, 41, 50 Vent part 24, 52 First vent 25 Second vent 26 Gate 27, 43, 51 Runner 30 Molded product 31 Die-cast molded product 32 Runner molded part 33 Burr 41a Vent groove 42 Vent part 43a Runner groove 44 Space 45 Mold part t1 First vent gap interval t2 Second vent gap interval d First vent width n1 First Exhaust direction length of vent gap interval n2 Exhaust direction length of second vent gap interval 60 Molding Metal mold 61 Molded product 62-65 First to fourth slide mold 66 Cavity 67 Vent part 68 First vent 69 Second vent 70 Fifth movable mold 71 End face 72 Molded product part 73 Vent mold part 74 Crevice space 75 Cylinder Space 76 Base end 77 Movable type

Claims (11)

It has a fixed type and a movable type that can move forward and backward with respect to this fixed type.
A mold for molding a molded product by filling a molten material through an introduction path into a cavity constituted by the fixed mold and the movable mold,
A vent portion for discharging gas is provided in a mold space constituted by the cavity and the introduction path,
The vent portion includes a first vent configured by a gap space extending in a planar shape that directly communicates with the mold space, and is continuous with the first vent on the exhaust tip side, and more gas than the first vent. And a second vent that is widely formed to reduce the airflow resistance.   The molding die according to claim 1, wherein a gap interval between the first vents is 0.05 to 0.30 mm.   The molding die according to claim 1 or 2, wherein the length of the first vent in the exhaust direction is 3 to 30 mm.   The said 2nd vent is comprised by the clearance gap space extended in the same direction as the said 1st vent, The clearance gap distance of this clearance gap is 0.35-2.00 mm, The any one of Claims 1-3 characterized by the above-mentioned. Mold for molding described in 1.   The molding die according to claim 4, wherein the second vent is formed with a width larger than that of the first vent.   The molding die according to any one of claims 1 to 3, wherein the second vent is configured by a cylindrical space that faces in a different direction from the first vent.   The molding die according to any one of claims 1 to 6, wherein a part or all of a part constituting the vent part is detachably formed with respect to the molding die. .   The molding die according to claim 7, wherein a part or all of a part constituting the vent part is made of a material different from that of the mold part provided with the vent part.   The molding die according to claim 1, wherein there is no overflow portion for allowing the molten material to flow out around the cavity. A molding method for molding using the molding die according to any one of claims 1 to 9,
A molding method characterized by increasing the gas discharge speed by the first vent and reducing the gas ventilation resistance after passing through the first vent by the second vent. It is a molded product that is molded by filling a molten material into a cavity constituted by a molding die,
A molded product, wherein the molding die is the molding die according to any one of claims 1 to 9.