JPH09220658A - Manufacture of manifold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a manifold having a desirable shaped runner highly precisely and inexpensively without applying complicated machining. SOLUTION: A first gate member 10, second gate member 12 and nozzle touch member 14 in which through-holes are formed are produced by a precision casting method. The nozzle touch member 14, first gate member 10 and second gate member 12 are joined so that the through-holes mutually communicate by a liquid phase diffusion joining method. After positioning a formed body 24 composed of three members 10, 12, 14 having a runner 26 constituted of three through-holes mutually communicated in a box, the manifold 34 inserted with metal 43 as cast-in is manufactured by casting the molten metal in the box.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a manifold, and more particularly, to a method for manufacturing a manifold which can be manufactured at low cost by encasing a molded body having a runner formed therein. Is.

[0002]

2. Description of the Related Art In an injection molding machine in which a thermoplastic resin or a thermosetting resin is heated and melted and the molten resin is injected into a mold under pressure to obtain a resin molded product having a required shape, a plurality of molds are used. A manifold for distributing and feeding the molten resin is used. In this manifold, a nozzle touch portion connected to the injection nozzle is formed on one surface, and a plurality of gate portions to which molds are respectively connected are formed on the other surface. The nozzle touch portion and the plurality of gate portions are formed. And are configured to communicate with each other via a runner formed by branching inside the manifold. Then, the molten resin pressed into the nozzle touch portion from the injection nozzle is distributed by the runner and is evenly injected into the corresponding mold through each gate portion,
As a result, a molded product is formed.

When forming a runner branching from the nozzle touch portion to, for example, two gate portions in the manifold, as shown in FIG. 10 (a), a first hole 62 is formed in the manifold main body 60 from the side surface. After that, as shown in FIG. 10B, the portion of the first hole 62 that opens on the side surface is blocked by blocking with a hole blocking member 74. Then, as shown in FIG.
A second hole 72 that is orthogonal to the first hole 62 and forms the nozzle touch portion 70 is bored from the rear surface side of the manifold main body 60 and penetrates the first hole 62. Further, a third hole 66 that is orthogonal to the first hole 62 and forms the gate portion 64 is formed from the front surface side so as to communicate with the first hole 62. At this time, by using a drill with a round tip, the first hole 6
R is formed on the orthogonal portion 68 of the second and third holes 66.

Runner 76 formed as described above
Since the other hole 72 is formed so as to be orthogonal to the first hole 62, the runner 76 bends at a right angle in the communicating portion, and the molten resin drifts or stays at that portion. When such a phenomenon occurs, the flow of the molten resin is disturbed, so that the flow of the molten resin injected from each gate portion 64 into the mold is also disturbed, resulting in uneven molding or uneven distribution of the molded product. There has been a problem that meat or the like is generated and the incidence of defective products is increased. Further, when the molten resin stays in the communicating portion of the runner 76, so-called resin burning or thermal decomposition fine particles of carbide are generated and adhered to the portion, which may be peeled off and mixed in the molded product, increasing the product defect rate. It was.

Therefore, the manifold is divided into two structures, and
A half groove is symmetrically formed on each surface where two divided bodies are pressed against each other.By pressing these two divided bodies, a runner of a desired shape is formed as a hollow path on the pressed surface. Proposed. According to this structure, the bent portion of the runner can be formed into a curved shape,
It is possible to prevent uneven flow and retention of the molten resin at the bent portion.

[0006]

The manifold having the above-mentioned divided structure is one in which the two divided bodies are pressed and brought into contact with each other and are supported and fixed by a frame body, but they are unavoidable on the mutual pressure-contact surfaces of the divided bodies. There is a possibility that a minute gap exists in the gap and the high-pressure molten resin exudes from the gap. In order to solve such a problem, it is sufficient to improve the processing accuracy of the mutual pressure contact surface of each divided body and to perform a treatment such that a minute gap is not generated during the assembly of the divided bodies. It is complicated and has been a cause of increasing the manufacturing cost of the manifold.

Therefore, the applicant of the present application has proposed a method of molding a member forming a part of the runner to be formed in the manifold to be manufactured by a precision casting method such as the lost wax method. In this method, the bent portion of the runner can be formed in a curved shape and a minute gap is not formed in the portion where the runner is formed, so that a product with a low defect rate can be mass-produced and the manufacturing cost can be reduced.

In this case, by joining and combining a plurality of members forming a part of the runner with each other, an entire manifold having a runner of a desired shape is manufactured. Then, it was a new issue whether or not they should be securely joined and combined.

[0009]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned problems inherent in the above-mentioned conventional techniques, and has been proposed to suitably solve the problems. It is an object of the present invention to provide a method for manufacturing a manifold that can be manufactured with high accuracy and low cost without performing the above.

[0010]

[Means for solving the problems] To overcome the above-mentioned problems,
In order to preferably achieve the intended purpose, the method for manufacturing a manifold according to the present invention is a runner as a whole by joining a plurality of members having through holes of a required shape so that the through holes communicate with each other. It is characterized in that a formed body is formed, and a molten metal is supplied and solidified in a state where the formed body is welded and fixed in a box to manufacture a manifold.

In order to preferably achieve the above-mentioned object, a method for manufacturing a manifold according to another invention of the present application comprises a pair of split bodies made of metal, and the split bodies are symmetrically formed on opposite surfaces thereof. While facing the grooves so that they match,
It is characterized in that it is manufactured by pressure bonding with an insert material made of a low melting point alloy interposed between the opposing surfaces.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a method for manufacturing a manifold according to the present invention will be described below with reference to the accompanying drawings with reference to preferred embodiments. In the embodiment, a case of manufacturing a manifold having two gate parts will be described.

First, as shown in FIG. 1, two gate members 10 and 12 each having an L-shaped through hole 10a and 12a formed in a substantially T-shaped metal block, and a T-shaped metal block having a substantially T-shape. One nozzle touch member 14 having a V-shaped through hole 14a is cast by a precision casting method such as the lost wax method. Briefly explaining this lost wax method, the periphery of the wax model created by the master pattern (prototype model) is wrapped with a surface coating material, and further around it, silica sand having a binder of ethyl silicate as a coating molding agent or A refractory powder such as zircon sand is filled to mold a precision mold, and after drying, the temperature is raised to melt the wax model. After that, the product is cast by firing the mold in a firing furnace and injecting the molten metal by centrifugal force, pressurization or reduced pressure casting. The structures of the gate members 10 and 12 and the nozzle touch member 14 will be described in more detail. In the first gate member 10 on the right side in FIG. 1, the left open end of the horizontal portion 10b and the vertical portion 1 are provided.
L-shaped through hole 10a that opens at the open end of 0c is formed, and in the second gate member 12 on the left side, the L-shaped through hole 12 that opens at the open end of the right side of horizontal part 12b and the open end of vertical part 12c.
a is formed, and in the nozzle touch member 14, the horizontal portion 14
A T-shaped through hole 14a is formed which opens at the left and right open ends of b and the open end of the vertical portion 14c. Through holes 10a, 12 of the respective members 10, 12, 14 cast by the precision casting method
Each of the bent portions of a and 14a is formed in a curved shape, and it is possible to prevent uneven flow and retention of the molten resin flowing in a runner 26 described later, which is constituted by these through holes 10a, 12a and 14a. It has become.

When engineering plastics containing glass fibers or resin containing ceramics is used as a molding material for the injection molding machine, abrupt wear of the inner wall of the runner poses a problem, so that the members 10 and 12 described above are used. , 1
As the material of No. 4, for example, 13 chrome stainless steel or tool steel, which can withstand the high temperature at the time of casting a molten metal described later and is excellent in wear resistance and corrosion resistance, is preferably used.

Each member 1 cast by the precision casting method
0, 12, and 14 are joined to each other by a liquid phase diffusion joining method. That is, first, between the right end surface of the horizontal portion 14b of the nozzle touch member 14 and the left end surface of the horizontal portion 10b of the first gate member 10, for example, an amorphous alloy (low melting point alloy) having a lower melting point than both members 10 and 14 is used. Both end faces are abutted against each other with the insert material 16 made of a material being interposed. This insert material 16 is formed in a ring shape as shown in FIG. 2, and the through holes 10a, 14a of both members 10, 14 communicate with each other with the insert material 16 interposed. As shown in FIG. 3, the two ends 10 and 14 of which the end faces are in contact with each other face each other, and the open end (right end face) of the horizontal portion 10b of the first gate member 10 is attached to the base 18 as shown in FIG.
In this state, the open end (left end surface) of the horizontal portion 14b of the nozzle touch member 14 is held in contact with the press 20, and the press 20 keeps a constant axial direction with respect to both horizontal portions 10b and 14b. Apply pressure P. Further, by heating the joint portion of both members 10, 14 with, for example, a low or high frequency induction coil 22, both members 10, 1
4 are joined. That is, the insert material 16 melted by heating by the induction coil 22 is
By diffusing to the end portions of 14, they are metallically bonded and a strong joint is made.

Next, the left end surface of the horizontal portion 14b to which the first gate member 10 of the nozzle touch member 14 is not joined,
The right end surface of the horizontal portion 12b of the second gate member 12 is opposed to and abuts with the insert material 16 interposed. Then, as shown in FIG. 4, with the open end (right end surface) of the horizontal portion 10b of the first gate member 10 installed on the pedestal 18, the open end of the horizontal portion 12b of the second gate member 12 is formed.
The (left end surface) is held in contact with the press 20, and a constant pressing force P is applied to both horizontal portions 12b and 14b in the axial direction by the press 20, and the joint portion is heated by the induction coil 22. As a result, the joining site is joined. As a result, as shown in FIG. 5, a molded body 24 in which the two gate members 10 and 12 are joined to the nozzle touch member 14 is obtained, and inside the molded body 24 are three through holes 10a, 12a and 14a. Runner 2
6 are formed.

The nozzle touch member 14 and the gate members 10 and 12 are joined to each other, for example, by setting the vacuum degree of the vacuum heating furnace to 1
/ 100,000 torr, heating temperature 1200 ° C., pressure P set to 0.5 kg / cm ² , and then an inert gas such as argon (Ar) is supplied to the bonding site to It is performed in a state where the vicinity is a non-oxidizing atmosphere. Then, the nozzle touch member 14 and the gate members 10 and 12 are reliably joined by holding the above conditions for about 1 hour.

Next, as shown in FIG. 6, a plurality of steel plates 30 for preparing a box 28 to be opened upward are prepared, and the box 2
8 at the required positions of the steel plates 30 and 30 located before and after the end of the molded body 24 to be the nozzle touch portion 36 and the gate portions 38 and 38 of the manifold 34 (the vertical portion 14c of the nozzle touch member 14 and each gate member). 10, 12
The through holes 30a through which the vertical portions 10c and 12c of FIG. Then, after the molded body 24 is welded in a state where the corresponding end of the molded body 24 is inserted into each through hole 30a, the box 28 is assembled with the plurality of steel plates 30. This allows box 2
Inside the body 8, the molded body 24 is positioned and fixed with the nozzle touch portion 36 and the gate portions 38, 38 facing outward. Further, inside the box body 28, the cavity 40 in which the molded body 24 is positioned and the runner 4 in which molten metal is poured.
2 is provided with a partition plate 44 to define the cavity 40
The runner 42 and the runner 42 are set to communicate with each other below the partition plate 44. The steel plate 30 and the partition plate 44 are made of mild steel or SS material.
(Rolled steel for general structure) Other SC material (Carbon steel for machine structure)
Is formed by using.

Further, since it is necessary to form a through hole for accommodating the thermocouple 46 and the heater 48 (see FIG. 7) in the manifold 34, the pipes 50, 52 positioned at corresponding portions in the cavity 40 are attached to the steel plate 30. Partition plate 44
Weld it to and fix it. The pipes 50 and 52 are made of an appropriate metal material that can withstand the high temperature when the molten metal is cast, and the inner diameter thereof is set to a size capable of accommodating the thermocouple 46 and the heater 48. The open ends of the pipes 50 and 52 positioned in the cavity 40 are configured so that molten metal does not enter.

Then, a molten metal such as 13 chrome stainless steel is cast into the runner 42 of the box 28 to form a cavity 4 in which the molded body 24 of the box 28 is located.
Zero is gradually filled with molten metal from below the partition plate 44. Thereby, the molded body 24 and the pipes 50, 52
Manifold 3 in which the metal 43 is integrally cast
4 is produced (see FIG. 7). The box 28 is pierced in the final finishing step and completely removed until the cast metal layer is exposed. In this case, since molten metal is cast into the cavity 40 from the bottom by the partition plate 44, the molded body 24 is locally melt-damaged or defects such as shrinkage cavities occur due to the molten metal cast. Can be suppressed. Further, it is recommended that the box 28 is housed inside a separately formed frame body, and molten metal is cast in a state where mold sand, steel shot, etc. are packed between the two.

That is, as in the embodiment, the nozzle touch member 14 having the through holes 10a, 12a, 14a forming the runner 26 and the gate members 10, 12 are joined to each other by a liquid phase diffusion bonding method using an amorphous alloy. By joining the joints to each other, it is possible to surely join by simply forming the end faces without performing a complicated work of forming a complicated groove at the joined portion. In addition, the molded body 24 is placed in the box 28.
The runner 26 can be provided at an accurate position by integrally surrounding the metal 43 with the metal being positioned by welding. Further, by pre-positioning the pipes 50 and 52 at the positions where the through holes for accommodating the thermocouple 46 and the heater 48 are formed inside the box 28, there is no need to form through holes by post-processing, and the number of steps Can be reduced and production efficiency can be improved.

As a method of manufacturing the nozzle touch member and the gate member, the divided structure shown in FIG. 8 can be adopted. That is, for example, in the case of manufacturing the gate member 53, the member 53 is composed of a pair of divided bodies 54 and 56, and a runner 26 is formed on the opposing surfaces of the divided bodies 54 and 56. Groove 54a, 5
6a is formed symmetrically. Then, the two divided bodies 54, 56
While the insert material 58 made of an amorphous alloy is interposed between the opposing surfaces of the two, the divided parts 54 and 56 are joined by applying a pressing force and heat to the joining part.
As a result, the gate member 5 having a curved bent portion is formed.
3 is manufactured. The insert material 58 is the divided body 5.
The grooves 54a, 56a of 4,56 are provided over the entire surface on which the grooves 54a, 56a are not formed.

In the gate member 53 formed by such a divided structure, the insert material 58 has the two divided bodies 54, 5
Since it is provided over the entire facing surface of No. 6, there is no gap between the two. That is, it is not necessary to increase the processing accuracy of the pressure contact surfaces of the divided bodies 54 and 56 and to separately perform a treatment that does not cause a gap, so that the manufacturing cost can be reduced. Then, after the two gate members are joined to the nozzle touch member manufactured by the similar divided structure to each other by the liquid phase diffusion joining method described above, the runner having a desired shape is formed by integrally casting with a metal. Manufactured manifold.

Further, as a method of manufacturing the manifold, the divided structure shown in FIG. 9 can be adopted. That is, the manifold 34 is composed of a pair of divided bodies 59, 61, and half-divided grooves 59a, 61a constituting the runner 26 are symmetrically formed on the opposing surfaces of the divided bodies 59, 61. Then, with the insert materials 63, 65 made of an amorphous alloy interposed between the facing surfaces of the two divided bodies 59, 61, the two divided bodies 59, 61 are joined by applying pressure and heat to the joining portions. To do. As a result, the manifold 34 having the bent portion formed in a curved shape is manufactured. In addition, the insert materials 63 and 65 are the divided body 5
The grooves 59a, 61a of 9,61 are provided over the entire surface on which the grooves 59a, 61a are not formed.

In the embodiment, the case where the nozzle touch member and the gate member are joined by the liquid phase diffusion joining method using the insert material has been described, but the present application is not limited to this, and for example, TIG welding or the like. Alternatively, both members may be fused together. Further, the manifold obtained by the manufacturing method of the present application can be used not only in the injection molding machine but also in an extrusion molding machine, and the molding material used in the molding machine may be metal. Further, in the embodiment, the pipe is used to form the through hole for accommodating the thermocouple and the heater, but a solid metal rod is used, and the through hole is formed by the cutting process in the final finishing step described later. Is also possible. In this case, by forming the solid metal rod with a material that can be easily cut, cutting in a later step becomes easier.

[0026]

As described above, according to the method for manufacturing a manifold of the present invention, the molten metal is supplied and solidified in a state in which the formed body having the runner is welded and fixed in the box. The manifold to be manufactured can be mass-produced at low cost. Moreover, since the molded body is fixed inside the box, the positional accuracy of the runner can be improved. Further, since each member is manufactured by the precision casting method, the bent portion of the runner can be formed in a curved shape, it is possible to prevent uneven flow and retention of the molding material flowing through the runner, and the defective rate of the product. Can be reduced. Furthermore,
By positioning and fixing the pipe in the box beforehand,
Since it is possible to omit the step of forming the hole for accommodating the thermocouple, the heater, etc., it is possible to reduce the number of steps, reduce the manufacturing cost, and improve the production efficiency.

By joining each member by a liquid phase diffusion joining method using a low melting point alloy, it is not necessary to form a complicated groove at the end of each member, and there is an advantage that processing is simple and no skill is required. . Further, in the case where each member is manufactured in a divided structure, by joining a pair of divided bodies by a liquid phase diffusion bonding method using a low melting point alloy, both divided bodies can be reliably joined without creating a minute gap. it can.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a nozzle touch member and a gate member that form a molded body according to an embodiment.

FIG. 2 is an explanatory perspective view showing a nozzle touch member, a first gate member, and an insert material according to the embodiment.

FIG. 3 is an explanatory diagram showing a state in which the nozzle touch member and the first gate member according to the embodiment are joined together.

FIG. 4 is an explanatory diagram illustrating a state in which a second gate member is joined to a nozzle touch member to which a first gate member according to the embodiment is joined.

FIG. 5 is an explanatory diagram showing a molded body in which two gate members are joined to the nozzle touch member according to the embodiment.

FIG. 6 is an explanatory view showing a state where the molded body and the pipe according to the embodiment are arranged inside the box.

FIG. 7 is an explanatory sectional view showing a manifold in which a molded body and a pipe according to an embodiment are integrally cast with metal.

FIG. 8 is an explanatory diagram showing a state in which the gate member according to the embodiment is manufactured by another method.

FIG. 9 is an explanatory diagram showing a state in which the manifold according to the embodiment is joined and manufactured.

FIG. 10 is an explanatory view showing a process of manufacturing a manifold by a method according to a conventional technique.

[Explanation of symbols]

 10 First Gate Member 10a Through Hole 12 Second Gate Member 12a Through Hole 14 Nozzle Touch Member 14a Through Hole 16 Insert Material 24 Molded Body 26 Runner 28 Box 34 Manifold 46 Thermocouple 48 Heater 50 Pipe 52 Pipe 53 Gate Member 54 Split Body 54a groove 56 division body 56a groove 58 insert material 59 division body 59a groove 61 division body 61a groove 63,65 insert material

Claims (7)

[Claims] 1. A plurality of members (10, 12, 14) having through holes (10a, 12a, 14a) having a required shape are joined so that the through holes (10a, 12a, 14a) communicate with each other. By doing so, a molded body (24) having a runner (26) formed as a whole is created.
A method for manufacturing a manifold, comprising manufacturing a manifold (34) by supplying and solidifying molten metal while the (24) is welded and fixed in the box (28). 2. The molten metal is supplied and solidified in a state where the pipes (50, 52) are positioned and fixed in a portion for accommodating the thermocouple (46), the heater (48) and the like in the box (28). The method for manufacturing a manifold according to claim 1. 3. The method of manufacturing a manifold according to claim 1, wherein the molded body (24) is formed of tool steel, and the molten metal poured into the box (28) is 13 chrome stainless steel. 4. The insert member (1) made of a low melting point alloy on the opposing surfaces to be joined of the plurality of members (10, 12, 14).
The method for manufacturing a manifold according to any one of claims 1, 2 and 3, wherein pressure bonding is performed with 6) interposed. 5. The method for manufacturing a manifold according to claim 1, 2, 3, or 4, wherein the members (10, 12, 14) are manufactured by a precision casting method. 6. The member (53) is composed of a pair of divided bodies (54, 56), and the grooves (54a, 56a) formed symmetrically on the opposite surfaces of the divided bodies (54, 56) are aligned with each other. So that they face each other,
Insert material (58) made of low melting point alloy on the opposite surface
The method for producing a manifold according to any one of claims 1, 2, 3 and 4, wherein the method is produced by pressure-bonding with the intervening pressure. 7. A pair of split bodies (59,61) formed of metal.
The split material (59, 61) is made of an insert material made of a low melting point alloy, and the grooves (59a, 61a) symmetrically formed on the opposite surfaces of the two divided bodies (59, 61) are opposed to each other so as to coincide with each other.
A method of manufacturing a manifold, which is manufactured by pressure bonding with (63, 65) interposed.