JP2005335189A - Valve gate type mold assembly and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve gate type mold assembly capable of smoothly holding a material passage and capable of enhancing the durability of a gate part, and its manufacturing method. <P>SOLUTION: A valve device 11 is incorporated in a fixed mold 1 and has a valve casing 12 having the material passage 15 formed therein and the valve pin 25 provided in the valve casing 12 to open and close a gate 14. The valve casing 12 is formed on an ultrahard material and composed of a small diameter part 13 having the gate 14 and a valve casing body 31. The joining surfaces 32 and 33 of the small diameter part 13 and the valve casing body 31 are pressed under predetermined pressure and a DC current and/or a pulse current is allowed to flow to temporarily join the joining surface 32 and 33 of the small diameter part 13 and the valve casing body 31, and the small diameter part 13 and the valve casing body 31 in the temporarily joined state are heat-treated at a predetermined atmospheric temperature to join the small diameter part 13 and the valve casing body 31. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a valve gate mold apparatus used for injection molding of a thermoplastic resin and the like, and a manufacturing method thereof.

  In a hot runner mold apparatus that heats the resin that is the molding material in the material passage to the gate to the product cavity and keeps it in a molten state at all times, a valve gate mold apparatus that mechanically opens and closes the gate with a valve pin is known. ing. The hot runner mold apparatus is intended to increase the molding efficiency, and the gate is closed to prevent the resin from leaking from the gate when the mold is opened.

  Here, a conventional valve gate mold apparatus will be described. The fixed mold and the movable mold, which are mold bodies, move relative to each other to open and close, and when the mold is closed, a product-shaped product cavity is formed between them. The fixed mold includes a fixed-side mold plate and a fixed-side receiving plate, and a gate that opens to the product cavity is formed on the fixed-side mold plate. A valve casing of the valve device is incorporated in an assembly hole formed through the fixed side receiving plate and the fixed side mold plate. The valve casing is substantially cylindrical, and a material passage communicating with the gate is formed at the center thereof. On the outer peripheral surface of the valve casing, there are provided a coil heater which is means for constantly keeping the thermoplastic resin which is a molding material in the material passage in a molten state, and a heater cover which covers the coil heater from the outside. A liner which is a material passage of a manifold is connected to the material passage of the valve casing, and a molding material is sent to the runner from an injection molding machine. A valve pin that opens and closes the gate of the gate bush by moving while being supported by a guide bush driven by a hydraulic cylinder or the like is provided in the valve casing. The valve pin is fitted to the gate of the gate bush to close it. At the time of molding, a plurality of molds are closed to form product cavities between the molds and the gate is opened, and the molding material is filled into the product cavities from the material passage through the gates. Next, the gate of the gate bush is closed by the valve pin, and after the molding material in the product cavity is solidified, the mold is opened and the molding material in the product cavity, that is, the molded product is taken out. Thereafter, the mold is closed again and the above molding cycle is repeated. Throughout the entire molding cycle, the molding material in the material passage of the valve casing is always kept in a molten state by the heating of the heating means.

  In the valve gate type mold apparatus as described above, in order to allow the resin to flow smoothly, the inner surface of the material passage is preferably smooth, and if the inner surface is rough, the occurrence of carbonized contamination due to resin stagnation or the like is caused. In particular, in a transparent product such as a lens, if contamination is mixed, molding failure occurs. Further, if the inner surface is rough, it takes time to change colors in multicolor molding or the like, and therefore it is preferable to finish the inner surface of the material passage smoothly.

  By the way, in the valve gate type mold apparatus as described above, there is one in which a gate is provided at the tip of the valve casing to facilitate the centering of the valve pin and the gate (for example, Patent Document 1). In this valve gate type mold apparatus, since the gate is provided at the tip of the valve casing, it is possible to obtain the concentric state of the valve pin and the gate only by aligning the valve casing and the valve pin.

  However, even if the concentric state of the valve pin and the gate is obtained, the valve pin fits the gate and closes the gate, so it is impossible to avoid wear of the valve pin and the gate due to long-term use. Or need to be replaced.

On the other hand, in patent document 1, the front-end | tip part provided with the gate is formed in a nest, and this nest is exchanged. On the other hand, there is a mold apparatus in which a material passage is formed between a plurality of mold constituent materials joined together by diffusion welding using a solvent (for example, Patent Document 2).
JP 2002-307492 A JP 2000-16784 A

  Therefore, although not known, the durability of the gate portion can be improved by forming the insert from a highly wear-resistant material and integrating it with the valve casing.

  However, when the insert is used, the structure of the valve casing tends to be complicated. Also, in diffusion welding using brazing material or solvent, if the nesting is made of a material different from that of the valve casing, sufficient joining strength cannot be obtained. Further, after joining, brazing material and solvent components are placed on the inner surface of the material passage. There is a risk that contamination will occur.

  The present invention is intended to solve such problems, and a valve gate mold apparatus capable of maintaining a smooth material passage and improving the durability of the gate portion, and a method for manufacturing the same. The purpose is to provide.

  The invention of claim 1 includes a plurality of mold bodies that open and close each other and form a product cavity therebetween when the mold is closed, and a valve device provided in a mold body having a gate that opens to the product cavity among these mold bodies. The valve device includes a valve casing that is incorporated in the mold and has a material passage formed therein, and a valve pin that is provided inside the valve casing and opens and closes the gate. In the valve gate mold apparatus in which the gate is formed, the valve casing includes the tip portion formed of a super hard material and a valve casing main body, and a joint surface between the tip portion and the valve casing main body is provided. While maintaining this pressed state, a direct current and / or a current is applied to the tip portion and the valve casing body. The tip current and the valve casing body are temporarily joined by flowing a current, and the tip and the valve casing body in the temporarily joined state are heat-treated at a predetermined atmospheric temperature, and the tip and the valve are heated. It is formed by joining the casing body.

  According to a second aspect of the present invention, there are provided a plurality of mold bodies that open and close each other and form a product cavity therebetween when the mold is closed, and a valve device provided in a mold body having a gate opening to the product cavity among these mold bodies. The valve device includes a valve casing that is incorporated in the mold and has a material passage formed therein, and a valve pin that is provided inside the valve casing and opens and closes the gate. In the manufacturing method of the valve gate type mold apparatus in which the gate is formed, the valve casing includes the tip portion formed of cemented carbide and the valve casing body, and the tip portion and the valve casing body are joined to each other. While pressing the surface with a predetermined pressure and holding the pressed state, a direct current is applied to the tip and the valve casing body. And / or a pulse current to temporarily join the joint surface between the tip portion and the valve casing body, and heat-treat the tip portion and the valve casing body in the temporarily joined state at a predetermined ambient temperature. is there.

  The invention of claim 3 is a manufacturing method in which the pressure is 50 megapascals or less.

  The invention of claim 4 is a manufacturing method in which the heat treatment is performed in an inert atmosphere.

  The invention of claim 5 is a manufacturing method wherein the temperature of the heat treatment is set to a temperature range of 55% to 85% of the lowest melting point of the members to be joined.

  According to the configuration of the first aspect, the tip portion of the different material and the valve casing main body can be joined, and when joining, the joint can be firmly joined without using any welding auxiliary material. The entire surface can be bonded uniformly. And the abrasion resistance of a gate can be improved by making the front-end | tip part which provided the gate into a super hard material.

  Further, since no welding auxiliary material is used, the welding auxiliary material does not appear in the material passage, and the inner surface of the material passage can be kept smooth.

  According to the configuration of claim 2, a valve casing formed by joining the tip portion of the different material and the valve casing body can be obtained, and can be firmly joined without using any welding auxiliary material at the time of joining, The entire joining surface can be joined uniformly. And the abrasion resistance of a gate can be improved by making the front-end | tip part which provided the gate into a super hard material.

  Further, since no welding auxiliary material is used, no welding auxiliary material appears in the material passage, and a valve casing having a smooth inner surface of the material passage can be obtained.

  Moreover, according to the structure of Claim 3, the enlargement of the apparatus for pressurization is not caused.

  Moreover, according to the structure of Claim 4, the quality of a joining location is stabilized by performing heat processing in inert atmosphere.

  Moreover, according to the structure of Claim 5, it is preferable on heat processing that the temperature of the said heat processing shall be 55 to 85% of the lowest melting | fusing point of the member which should be joined.

  Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below do not limit the contents of the present invention described in the claims. In addition, all of the configurations described below are not necessarily essential requirements of the present invention. In the embodiment, by adopting a new valve gate type mold apparatus different from the conventional one and its manufacturing method, an unprecedented valve gate type mold apparatus and its manufacturing method can be obtained, and the valve gate type mold apparatus is obtained. And its manufacturing method.

  1 to 4 show an embodiment 1 of the present invention. In the figure, 1 is a fixed mold, 2 is a movable mold, and these fixed bodies are mold bodies. The mold 1 and the movable mold 2 are opened and closed by moving in the illustrated vertical direction (mold opening / closing direction) in FIG. 1, and a product-shaped product cavity 3 is formed between them when the mold is closed.

  The fixed mold 1 includes a fixed-side mold plate 4 as a main body portion, and a fixed-side receiving plate 5 fixed to a surface of the fixed-side mold plate 4 opposite to the movable mold 2. A cavity block 7 that forms the product cavity 3 is embedded and fixed to the stationary side template 4, and a casing built-in hole 8 that opens to the product cavity 3 is formed at the tip of the cavity block 7. . A valve casing 12 of the valve device 11 is incorporated in an assembling hole 9 formed through the fixed side receiving plate 5 and an assembling hole 10 formed in the cavity block 7, and a tip end portion of the valve casing 12 is provided. A small-diameter portion 13 is incorporated in the casing assembling hole 8 in a fitted state. The valve casing 12 is made of metal and has a substantially cylindrical shape. A gate 14 that opens to the product cavity 3 is formed at the tip of the small diameter portion 13. Note that the casing assembling hole 8 and the assembling hole 10 are concentric and communicated with each other.

  The inside of the valve casing 12 is a material passage 15 that communicates with the gate 14. On the outer peripheral surface of the valve casing 12, there is a band heater 16 that is a means for keeping the thermoplastic resin as a molding material in the material passage 15 in a molten state at all times, and a heater cover 17 that covers the band heater 16 from the outside. Is provided. The valve casing 12 is provided with a temperature sensor 18 along the inside of the band heater 16.

  The base end portion of the valve casing 12 is a flange portion 19 which is fixed and supported between the manifold 20 and the fixed side receiving plate 7. A nesting 21 and a guide bush 22 which is a valve pin support portion are fixed to the base end portion of the valve casing 12. The guide bush 22 passes through the insert 21. The material passage 15 in the valve casing 12 communicates with the runner 24 in the manifold 20 through a bent portion 23.

  The valve casing 12 incorporates a substantially cylindrical valve pin 25 that moves in the mold opening / closing direction and opens / closes the gate 14 by driving a driving device such as a hydraulic cylinder device (not shown). The valve pin 25 is configured such that a gate closing portion 26 formed as a straight portion at a distal end portion thereof is detachably fitted to the gate 14 to close the gate 14. The valve pin 25 has the mold opening / closing direction as an axial direction and passes through the linear material passage 15 coaxially, but is formed on the gate 14 side of the valve casing 12 and inside the valve pin support hole 27. The outer peripheral surface is slidably in contact with the edge at all times.

  As shown in FIG. 2, the valve pin support hole 27 is composed of a plurality of radial support blades 28, and the tip of the valve pin 25 on the gate 14 side is slidably supported. Further, a concave groove 29 that communicates the material passage 15 and the gate 14 is formed between the support blades 28. The valve pin 25 is supported by the guide bush 22 on the manifold 20 side. That is, the valve pin 25 slidably penetrates through the guide bush 22.

  The valve casing 12 has a small-diameter portion 13 which is a tip portion thereof divided separately, and is provided with the small-diameter portion 13 and a valve casing main body 31, and a joining surface 32 of the small-diameter portion 13 and a joining surface 33 of the valve casing main body 31 are provided. Joined. In this example, the support blades 28 are provided in the material passage 15 on the valve casing body 31 side. Further, the material passage 15 of the small diameter portion 13 is formed so as to become smaller toward the gate 14 from the opposite gate side.

  The small-diameter portion 13 is made of a carbide material that is different from the valve casing body 31 and has higher wear resistance than the valve casing body 31. As this cemented carbide, it is preferable to use powder high-speed tool steel (powdered high-speed steel / HAP), and since powder high-speed tool steel is excellent in wear resistance and cutting resistance, it is manufactured. This makes it easy to polish and make adjustments and repairs. Then, the joint surfaces 32 and 33 are processed into flat surfaces, preferably mirror surfaces. The joint surfaces 32 and 33 may be rough surfaces (surface roughness is about ▽ in JIS standard), but it is preferable to process the mirror surface because the joint strength of the member is high and deformation due to the joint can be reduced. The numerical range of the mirror surfaces at the joint surfaces 32 and 33 is not necessarily clear, but here refers to a surface processed state having a smoothness with a numerical value of Ra 0.3 or less (the smaller the numerical value, the higher the smoothness). Further, it is preferable that the support blades 28 are polished from the front end side of the valve casing body 31 and the inner surface of the material passage 15 in the small diameter portion 13 is also polished before joining. That is, after joining, the support blade 28 and the material passage 15 cannot be polished from the small gate 14.

  In this way, since the material passage 15 before joining is polished, the surface of the support blade 28, which has been difficult to achieve with an integral structure, can also be polished.

  After the polishing is completed, the joining surfaces 32 and 33 are aligned with each other, and the valve casing main body 31 and the small diameter portion 13 are overlapped with each other using a known positioning means, and the valve casing main body 31 and the small diameter portion 13 are overlapped with each other. The combined laminated body 12S is mounted on an energization joining apparatus, and the joining surfaces 32 and 33 are joined.

  FIG. 4 shows the overall configuration of the current-carrying apparatus of this example. As shown in the figure, the energization joining apparatus T of this example includes an energization joining machine 70 and a heat treatment machine 80. The energization bonding machine 70 is disposed above the base 72 and a lower energizing electrode 73 that is electrically insulated from the base 72 and fixed on the base 72 by a known method via an insulating member. A fluid pressure cylinder 74 supported on the base 72 by a known method, and fixed to the tip of the piston rod 75 of the fluid pressure cylinder 74 by an insulation member and electrically insulated from the piston rod 75 by a known method. And an upper energizing electrode 76.

  The fluid pressure cylinder 74 functions as a pressurizing device that presses the material to be joined. As the pressurizing device, the upper energizing electrode 76 may be moved up and down using an electric motor, a screw mechanism or the like instead of the fluid pressure cylinder. The upper and lower energization electrodes 73 and 76 are electrically connected to a power supply device 77, and the power supply device 77 can supply a DC pulse current. The power supply of the power supply device 77 of this example is a large current power having a voltage of 100 V or less and a current in the range of 2000 to 5000A. In this example, the upper energizing electrode 76 can be moved, but conversely, the lower energizing electrode 73 can be moved, or both can be moved.

  Next, the heat treatment machine 80 includes a vacuum heat treatment furnace having a known structure. It should be noted that the current bonding machine 70 and the heat treatment machine 80 can be integrated into a device configuration, or these can be moved. Of course, these may be arranged separately.

  Next, a procedure for joining the valve casing main body 31 and the small diameter portion 13 constituting the laminated body 12S to each other using the energization joining apparatus T having this structure will be described.

  First, the laminate 12S is sandwiched between the energizing electrodes 73 and 76, the fluid pressure cylinder 74 is driven, and the upper energizing electrode 76 is lowered by the piston rod 75. As a result, the laminated body 12S is sandwiched between the energizing electrodes 73 and 76 and is pressed with a predetermined pressing force. A predetermined pressing force is applied between the valve casing body 31 and the joining surfaces 32 and 33 of the small diameter portion 13. Although this pressing force varies depending on the material of the member, it may be 50 megapascals or less.

  As a result, the joint surfaces 32 and 33 are joined to each other. Although the exact principle of this joining is not necessarily clear, it is thought that joining is performed by the generation of discharge plasma between joining surfaces, the thermal diffusion effect by Joule heat, the electrolytic diffusion effect by an electric field, and the like.

  Here, it is possible to form a state in which the joining surfaces 32 and 33 are joined to each other even when only a direct current of a predetermined value is passed through the laminated body 12S, or when both a direct current and a pulsed current are passed simultaneously. confirmed.

  The state in which the joint surfaces 32 and 33 are joined in this manner is not yet complete from the viewpoint of joining strength. Therefore, this bonded state is referred to as a temporary bonded state, and the laminate 12S in the temporary bonded state is referred to as a temporary bonded body.

  This temporary joined body is heat-treated in an inert atmosphere in a heat treatment furnace of the heat treatment machine 80. The heat treatment temperature and time vary depending on the material and size of the member, but the heat treatment temperature is desirably in the temperature range of 55% to 85% of the lowest melting point of the members to be joined. By performing the interdiffusion heat treatment, the joint between the joint surfaces 32 and 33 in the temporarily joined state becomes perfect and becomes a completely joined body. That is, the valve casing 12 in which the joint strength between the joint surfaces 32 and 33 is comparable to the material strength of the member is obtained. Note that annealing is performed after the mutual diffusion processing is performed.

  The current used in the bonding method and apparatus used in the present invention is a direct current, a pulse current, and a combination current of a direct current and a pulse current. Among these, a pulse current and a combination current of a direct current and a pulse current are used. In some cases, a pulse current always flows, so it can be called a pulse energization joining method and apparatus.

  Moreover, this joining method has the following effects. There is no need to use a graphite mold unlike the conventional spark plasma sintering method. Joining is possible without using any welding aids. The entire joining surface can be joined uniformly over the entire surface. It can be easily joined only by making the joining surface flat. The joint strength can be increased by increasing the planar accuracy of the joint surface. The joint strength can be made the same as the strength of the material of the metal member to be joined. Bonding can be performed with a small deformation of the bonding portion. There is no need for post-processing such as removal of welding aids and wax around the joint. It is possible to easily join the fine portions. Since the parts to be joined can be joined after being completed as parts, those having complicated shapes can be assembled by joining. It is possible to join without impairing the properties of the members to be joined. Metal members of different materials can be easily joined. Bonding is possible by appropriately controlling the temperature of the portion other than the bonding portion. A plurality of parts having different shapes can be joined simultaneously.

  Through the heat treatment described above, the valve casing 12 shown in FIG. 1 is obtained. In the valve casing 12, the valve casing 12 including the gate 14 made of super hard material is formed by joining the valve casing main body 31 and the small diameter portion 13. Therefore, it is possible to obtain the gate 14 that is superior in wear resistance as compared with the prior art. In addition, since the joining can be performed without using any welding auxiliary material, the welding auxiliary material does not come out in the material passage 15 after joining, and the inner surface of the material passage 15 can be kept smooth. The insert 21 is joined to the valve casing body 31 when the valve casing body 31 and the small diameter portion 13 are joined and then joined to the valve casing body 31 and before the valve casing body 31 and the small diameter portion 13 are joined. It is possible to appropriately select the case and the case where the insert 21, the valve casing main body 31 and the small diameter portion 13 are simultaneously joined by the energization joining device T.

  Further, according to the method of this example, the joint strength between the valve casing body 31 and the small diameter portion 13 made of different metal materials can be made as strong as the base material strength. Even if the casing 12 is configured, no malfunction occurs.

  When molding, first, the fixed mold 1 and the movable mold 2 are closed, a product cavity 3 is formed between the fixed mold 1 and the movable mold 2, and then the valve pin 25 is moved away from the movable mold 2. The gate 14 is opened. Then, a molten thermoplastic resin, which is a thermoplastic molding material, is injected into the fixed mold 1 from the injection molding machine. This resin passes through the runner 24 of the manifold 20 and the like, and further passes through the material passage 15 in the valve casing 12 and the concave groove 29 between the support blades 28 into which the valve pin 25 is fitted, and the gate 14 at the tip of the valve casing 12. Into the product cavity 3. After the resin is filled in the product cavity 3 in this way, after holding pressure, the valve pin 25 moves toward the movable mold 2 and fits into the gate 14 to close the gate 14. Then, after the resin in the product cavity 3 is cooled and solidified, the fixed mold 1 and the movable mold 2 are opened, and the resin in the product cavity 3, that is, the molded product is taken out. Thereafter, the mold is closed again and the above molding cycle is repeated.

  Thus, the valve pin 25 is repeatedly fitted to the gate 14 by repeating the molding cycle. However, since the gate 14 is formed in the small-diameter portion 13 made of a super hard material, the wear resistance is excellent.

  Thus, in the present embodiment, corresponding to claim 1, a plurality of fixed molds 1 and movable molds 2 that are opened and closed with each other and form a product cavity 3 between the molds when the mold is closed, And a valve device 11 provided in the movable mold 2 which is a mold body having a gate 14 opened to the product cavity 3 of the movable mold 2. The valve device 11 is incorporated in the fixed mold 1 and has a material passage 15 therein. In the valve gate mold apparatus having the valve casing 12 formed in the valve casing 12 and the valve pin 25 provided inside the valve casing 12 for opening and closing the gate 14, and forming the gate 14 at the tip of the valve casing 12, the valve casing 12 includes a small-diameter portion 13 which is a tip portion made of super hard material and a valve casing body 31, and presses the joining surfaces 32 and 32 of the small-diameter portion 13 and the valve casing body 31 with a predetermined pressure. While holding the pressed state, a direct current and / or a pulse current is passed through the small diameter portion 13 and the valve casing body 31 to temporarily join the joining surfaces 32 and 33 of the small diameter portion 13 and the valve casing body 31. Since the small-diameter portion 13 and the valve casing body 31 in a joined state are heat-treated at a predetermined atmospheric temperature and the small-diameter portion 13 and the valve casing main body 31 are joined, Can be joined without using any welding auxiliary material, and the entire joining surfaces 32 and 33 can be joined uniformly. The wear resistance of the gate 14 can be improved by making the small diameter portion 13 provided with the gate 14 a super hard material. Further, since no welding auxiliary material is used, no welding auxiliary material appears in the material passage 15, and the inner surface of the material passage 15 can be kept smooth.

  In this way, in this embodiment, corresponding to claim 2, the fixed mold 1 and the movable mold 2, which are a plurality of mold bodies that open and close each other to form the product cavity 3 when the mold is closed, and these fixed molds 1 and a movable die 2 having a gate 14 that opens to the product cavity 3. The valve device 11 is provided in the movable die 2. The valve device 11 is incorporated in the stationary die 1 and the material passage 15. Of a valve gate type mold apparatus having a valve casing 12 formed inside and a valve pin 26 provided inside the valve casing 12 for opening and closing the gate 14 and having the gate 14 formed at the tip of the valve casing 12 In the method, the valve casing 12 includes a small-diameter portion 13 that is a tip portion formed of a super hard material and a valve casing main body 31, and the joining surfaces 32 and 33 between the small-diameter portion 13 and the valve casing main body 31 are provided with a predetermined pressure. While holding the pressed state with a force, a direct current and / or a pulse current is passed through the small diameter portion 13 and the valve casing body 31, and the joining surfaces 32, 33 of the small diameter portion 13 and the valve casing body 31 are moved. Temporary joining is performed, and the small-diameter portion 13 and the valve casing body 31 in the temporarily joined state are heat-treated at a predetermined atmospheric temperature, so that a valve casing formed by joining the tip portion 13 and the valve casing body 31 of different materials is obtained. In the joining, joining can be performed without using any welding auxiliary material, the small-diameter portion 13 and the valve casing body 31 can be joined firmly, and the entire joining surfaces 32 and 33 can be joined uniformly. The wear resistance of the gate 14 can be improved by making the small diameter portion 13 provided with the gate 14 a super hard material. Further, since no welding auxiliary material is used, the welding auxiliary material does not appear in the material passage 15 of the valve casing 12, and the valve casing 12 having a smooth inner surface of the material passage 15 is obtained.

  As described above, in this embodiment, the pressure is set to 50 megapascals or less in correspondence with the third aspect, so that the apparatus for pressurization is not increased in size.

  In this way, in this embodiment, the heat treatment is performed in an inert atmosphere corresponding to the fourth aspect, so that the quality of the joint portion is stabilized.

  In this way, in this embodiment, in correspondence with claim 5, the temperature of the heat treatment is set to a temperature range of 55% to 85% of the melting point of the members to be joined. A state is obtained.

  Further, as an effect on the embodiment, since the material passage 15 and the support blade 28 are polished and then temporarily joined, even if the temporary joining is performed after the grinding, the welding auxiliary material is not used. It can be kept smooth.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible. For example, the shape of the material passage can be selected as appropriate.

It is sectional drawing of the valve gate type metal mold | die apparatus which shows Example 1 of this invention. It is sectional drawing of the front end side of a valve casing same as the above. It is a front view of the front-end | tip part and valve casing main body before joining same as the above. It is a schematic block diagram of an energization joining apparatus same as the above.

Explanation of symbols

1 Fixed type
2 Movable type (form)
3 Product cavity
11 Valve device
12 Valve casing
13 Small diameter part (tip)
14 Gate
15 Material passage
25 Valve pin
32 Joint surface
31 Valve casing body
33 Joint surface

Claims (5)

A plurality of mold bodies that open and close each other and form a product cavity between them when the mold is closed, and a valve device provided in a mold body having a gate that opens to the product cavity among these mold bodies, A valve casing that is incorporated in the mold and has a material passage formed therein, and a valve pin that is provided inside the valve casing and opens and closes the gate, and the gate is formed at the tip of the valve casing. In the gate-type mold apparatus, the valve casing includes the tip portion formed of a super hard material and a valve casing body, and presses a joint surface between the tip portion and the valve casing body with a predetermined pressure. While maintaining the pressed state, a direct current and / or pulse current is passed through the tip and the valve casing body. , Temporarily joining the joint surface between the tip portion and the valve casing body, heat treating the tip portion and the valve casing body in the temporarily joined state at a predetermined atmospheric temperature, and joining the tip portion and the valve casing body A valve gate mold apparatus characterized by comprising: A plurality of mold bodies that open and close each other and form a product cavity between them when the mold is closed, and a valve device provided in a mold body having a gate that opens to the product cavity among these mold bodies, A valve casing that is incorporated in the mold and has a material passage formed therein, and a valve pin that is provided inside the valve casing and opens and closes the gate, and the gate is formed at the tip of the valve casing. In the method for manufacturing a gate-type mold apparatus, the valve casing includes the tip portion formed of cemented carbide and a valve casing body, and presses a joint surface between the tip portion and the valve casing body with a predetermined pressure. While maintaining this pressed state, a direct current and / or pulse current is applied to the tip and the valve casing body. The valve gate type is characterized in that the joint surface between the tip portion and the valve casing body is temporarily joined, and the tip portion and the valve casing body in the temporarily joined state are heat-treated at a predetermined ambient temperature. Manufacturing method of mold apparatus. 3. The method of manufacturing a valve gate type mold apparatus according to claim 2, wherein the pressure is 50 megapascals or less. 4. The method for manufacturing a valve gate mold apparatus according to claim 2, wherein the heat treatment is performed in an inert atmosphere. 5. The valve gate mold apparatus according to claim 2, wherein the temperature of the heat treatment is in a temperature range of 55% to 85% of the lowest melting point of the members to be joined. Method.

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