JPH11129289A - Mold for injection molding of thermosetting resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold for injection molding of a thermoplastic resin which shortens the time from preparation of the mold to manufacturing of a product, prevents the charged amt. of molding material after variation is adjusted from being changed, and improves the degree of freedom of cavity layout. SOLUTION: A fixed side mold 2 is constituted by piling up a cold runner plate 7 and a fixed side cavity plate 10 and a cold runner 16 is provided on the cold runner plate 7 and the cold runner 16 is made to branch into a plurality of cold runner parts 17 and a plurality of cold nozzles 11 for introducing a thermosetting resin into each product cavity part 29 are inserted into the fixed side cavity plate 10 from each cold runner part 17. In addition, a plurality of flow rate adjusting pins 40 for controlling resistance to the flow of the thermosetting resin of each cold runner part 17 are inserted into the cold runner plate 7. By adjusting the flow of the thermosetting resin by means of the flow rate adjusting pins, the amt. of resin charged into each product cavity part 29 is uniformed and it is expected that variation adjusting work is smoothed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for injection molding of a thermosetting resin related to LIM molding (Liquid Injection Molding) using liquid silicone rubber, and more particularly, to a method of molding a plurality of cold runner portions. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosetting resin injection mold capable of controlling resistance to the flow of a curable resin and easily adjusting a charge amount of a molding material to a cavity.

[0002]

2. Description of the Related Art A cold runner system for a mold for injection molding of a thermosetting resin is called a so-called runner-less system, and is a rational manufacturing method capable of reducing a surplus material so as not to harden a runner. Prior art documents of this type of injection mold include JP-A-62-16114, JP-A-63-141714, and JP-A-5-13868.
However, these prior art documents all disclose a sprueless or flashless type mold for a thermosetting resin.

[0003]

Each of the above prior art documents discloses a sprueless or flashless type mold, but these have the following problems. First, in the cold runner method, when the cold runner is formed by branching into at least two or more cold runner portions, the variation of the charge amount for each cavity portion is caused by a cold runner portion, a nozzle of an injection molding machine,
And the processing accuracy of the gate and the temperature balance of the cold runner plate. It is sufficient that these variations can be completely adjusted and suppressed at the time of initial processing, but this is practically very difficult. Therefore, in the related art, the cold runner portion, the nozzle, and the gate on the side where the flow rate of the resin is small are cut while performing the trial production several times, in other words, in other words, the so-called try and error is repeatedly adjusted and suppressed. .

[0004] However, the above operation requires disassembling and assembling the mold each time. Moreover,
As the number of branches in the cold runner section increases, the work load increases. Therefore, conventionally,
There has been a problem that the work requires an enormous loss of time and labor.

Conventionally, even after the variation is adjusted, if the temperature balance of the cold runner plate is lost during molding running, or if the molding material is changed to one having a different fluidity, the molding material is charged into each cavity. There was a problem that the amount changed. Further, in the related art, the cold runner is usually designed so that the length to the gate position is equal to minimize the variation in the charge amount during the initial processing. However, such a design significantly impairs the flexibility of the cavity layout.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional problems, and can reduce the time from the production of a mold to the start of a product, and can prevent the charge amount of a molding material from changing after adjusting for variations. Moreover, it is an object of the present invention to provide a mold for injection molding of a thermosetting resin capable of improving the degree of freedom in the layout of the cavity.

[0007]

According to the first aspect of the present invention, in order to achieve the above object, a fixed mold and a movable mold are clamped, and a plurality of cavities between them are heated. In what is filled and molded with a curable resin, a plate and a cavity plate are laminated to constitute the fixed mold, a cold runner is provided inside the plate, and the cold runner is divided into a plurality of cold runner portions. And a plurality of cold nozzles for guiding the thermosetting resin from each cold runner section to each cavity section inside the cavity plate, and controlling the resistance of each cold runner section to the flow of the thermosetting resin. It is characterized by comprising adjusting means. Each of the cavities may have a flashless structure.

[0008] Further, means for cooling the plurality of cold runner portions and the plurality of cold nozzles, heating means for the cavity plate, and heat insulating means interposed between the plate and the cavity plate are provided. It is preferred to include. Further, the flow rate adjusting means includes a plurality of flow rate adjusting pins, a part of which is inserted into the plate, and a tip on a partial side of each flow rate adjusting pin is capable of moving forward and backward with respect to the inside of the cold runner portion. At the same time, the rest of each flow control pin can be exposed to the outside of the plate to enable operation. Further, the flow rate adjusting means includes a plurality of flow rate adjusting pins partially inserted into the plate, and a flow path forming a part of the cold runner portion is provided in a part of each flow rate adjusting pin, The remaining portion of the flow control pin can be exposed to the outside of the plate to be operable.

Here, the term "thermosetting resin" in the claims must be understood in a broad sense by paying attention to technical ideas, and includes so-called resins and rubbers. Among these resins, at least phenol resin, urea resin, melamine resin, guanamine resin, melamine phenol resin, epoxy resin, alkyd resin, polyimide,
Examples include diallyl phthalate resin, unsaturated polyester resin, and silicone resin. Also, after curing, butyl rubber, ethylene propylene rubber, which becomes a rubber-like elastic body,
Silicone rubber, fluorine rubber, styrene butadiene rubber, or acrylonitrile butadiene rubber is also included.

[0010] The rubber includes silicone rubber,
A typical example is urethane rubber or tolyl rubber. Further, the thermosetting resin may be a resin to which various additives for imparting properties, for example, a lubricant, a reinforcing agent, a coloring agent, a flame retardant, or the like are added. Further, the “plate” can be composed of two or more plates in consideration of easiness of processing and easiness of maintenance. Further, the “cold runner” is branched and distributed into two or more cold runner portions having a linear shape or a curved shape, and is formed in various shapes such as a spoke shape as a whole.

According to the first aspect of the present invention, since the flow rate adjusting means appropriately controls the flow of the thermosetting resin in each cold runner portion, the filling amount of the thermosetting resin into the plurality of cavities is substantially uniform. Becomes According to the second aspect of the present invention, in the predetermined cavity portion,
No burrs are generated from the parting surface, and no back-riding phenomenon (a phenomenon in which dents, tears, sink marks, or the like occur in places where mold joints or material flows out) occurs. Further, according to the third aspect of the present invention, the cold runner system can be kept at a low temperature by the cooling means, and the loss of the molding material in this portion can be reduced. Further, since the heating means heats the respective portions of the cavity plate almost uniformly, a molded product cured uniformly can be obtained. Furthermore, since the heat insulation means is located between the plate and the cavity plate,
The temperature of the cold runner system and the temperature of the cavity plate can be controlled separately.

According to the fourth aspect of the present invention, when the remaining portion of the flow control pin is operated by sliding or turning, the tip of the flow control pin protrudes into each cold runner portion, Alternatively, the tip of the flow rate adjusting pin is retracted from the inside of each cold runner section toward the wall. Further, since the flow rate adjusting pins can be operated from outside the plate, the flow of the thermosetting resin can be adjusted even during molding. According to the fifth aspect of the present invention, when the remaining portion of the flow rate adjusting pin is operated by sliding or turning, the position of the flow passage is shifted or shifted from the position forming each cold runner portion. It returns from the position to the original position and forms a part of each cold runner part.
Thereby, the cross-sectional area of each cold runner part changes substantially. Furthermore, since the flow rate adjusting pins can be operated from outside the plate, the flow of the thermosetting resin can be adjusted even during molding.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments. As shown in FIG. 1, a thermosetting resin injection mold 1 according to the present embodiment includes a cold runner type fixed mold 2 and a movable mold 3.
The fixed mold 2 is attached to the fixed die plate of the injection molding machine (not shown), and the movable mold 3 is attached to the movable die plate of the injection molding machine. Is attached.

The fixed side mold 2 includes a fixed side mounting plate 5, a first plate 6, a cold runner plate 7, a heat insulating plate 8, a second plate 9, and a fixed side cavity plate 10 sequentially from above to below in FIG. A plurality of cold nozzles 11, cooling means 12, and heating means 1
3 built-in. The fixed-side mounting plate 5 has a sprue bush and a locating ring fitting hole 14 formed in the center thereof, and is mounted on the fixed-side die plate via bolts.
The first plate 6 is provided with a fitting hole 15 communicating with the fitting hole 14 at the center thereof, and is mounted on the bottom surface of the fixed-side mounting plate 5 via a bolt.

The cold runner plate 7 is made of, for example, S
It is configured using a C material or the like, and is mounted on the bottom surface of the first plate 6. As shown in FIGS. 1 and 2, a cold runner 16 having a circular cross section communicating with the fitting hole 15 of the first plate 6 is provided inside the cold runner plate 7. A plurality (four in the present embodiment) of cold runner portions 17 are formed in a system in a system having an H-shaped cross section for individual cutting. Each of the branched cold runner portions 17 is, for example, φ
It is formed to 5 mm. A plurality of recesses 18 are arranged on the bottom surface of the cold runner plate 7 with the openings facing downward so that the distances to the fitting holes 14 and 15 are equal.

The heat insulating plate 8 and the second plate 9 include:
Communication holes 19 and 20 communicating with the plurality of recesses 18 of the cold runner plate 7 are arranged and formed. Also,
The fixed-side cavity plate 10 is made of, for example, an SC material, and is mounted on the bottom surface of the second plate 9. The fixed side cavity plate 10 is formed with an array of communication holes 21 communicating with the plurality of communication holes 19, 20. Each of the communication holes 21, the communication hole 20 of the second plate 9, the communication hole 19 of the heat insulating plate 8, and Each recess 18 is a vertically long space 2
2 are formed. Fixed side cavity plate 10
A plurality (four in the present embodiment) of fixed-side cavities 23 are arrayed and formed on a parting surface (indicated by PL in FIG. 1) which is the bottom surface of. Each fixed-side cavity 23 has, for example, a diameter of φ40 mm and a height of 5 m in consideration of a material shrinkage ratio and the like.
m.

Each cold nozzle 11 has a plurality of spaces 22.
It is inserted vertically in the center of. Each cold nozzle 11
Has a flow diameter of, for example, φ5 mm, a lower end portion connected to each fixed side cavity 23 through a gate 24, and an upper end portion connected to each cold runner portion 17. I have. The gate 24 has a diameter of, for example, 0.5 mm and a straight portion of 3 mm. Each of the cold nozzles 11 and the gate 24 thus configured constitutes an open nozzle whose passage is always open.

The cooling means 12 comprises a continuously curved cooling water passage 120, both ends of which are connected to a cooling mechanism (not shown) with a pump, and the rest of the cooling water passage 120 being connected to the cold runner plate 7. It is built in and located below the cold runner 16 and the plurality of cold runner sections 17. A part of the remaining portion of the cooling water channel 120 is formed in a plurality of water jackets 121, each of which is housed in a plurality of spaces 22 and located near the periphery of the cold nozzle 11. The cooling means 12 configured as described above circulates cooling water of, for example, 15 ° C., and cools the cold runner 16, the plurality of cold runner units 17, and the plurality of cold nozzles 11, respectively.

The heating means 13 is a rod-shaped cartridge heater 130 appropriately selected according to the curing temperature of the resin to be molded.
A plurality of the cartridge heaters 130 are built in the fixed-side cavity plate 10 at intervals. The heating means 13 configured in this manner functions to uniformly heat the fixed-side cavity plate 10 and each fixed-side cavity 23 at, for example, 160 ° C.

The movable mold 3 is provided with a movable cavity plate 25, a block 26, and a movable mounting plate 27 for a movable die plate which are sequentially laminated from above to below in FIG. 1, and includes a heating means 13A. doing. The movable side cavity plate 25 is placed on the block 26,
Multiple movable cavities 2 on the parting surface
8 are arranged. Each of the plurality of movable cavities 28 also takes into account the material shrinkage rate and the like, and for example, has a diameter φ
A plurality of product cavities 29 are formed together with the plurality of fixed-side cavities 23 of the fixed-side mold 2 by being cut into a disk shape having a height of 40 mm and a height of 5 mm. Each product cavity 29
Is formed in a disk shape having a diameter of, for example, 40 mm and a height of 10 mm, and has a flashless structure in which a thermosetting resin does not protrude during molding. Since the heating means 13A is substantially the same as described above, the description is omitted.

Further, as shown in FIGS. 1 to 3, the flow rate adjusting means 4 includes a plurality (four in this embodiment) of flow rate adjusting pins 40 having rounded tips. Each flow adjustment pin 4
A part 0 is rotatably inserted into the cold Nanner plate 7 via a nut or the like so as to be able to move forward and backward through a nut or the like, and the front end penetrates the wall of each cold runner part 17 and is located inside. . On the other hand, the remaining portion on the end side of each flow rate adjustment pin 40 projects horizontally to the outside of the cold Nanner plate 7, and can be operated from outside.

In order to manufacture an O-ring or a cap by injection molding in the above-described configuration, first, the flow rate of the thermosetting resin is adjusted in advance by operating a plurality of flow rate adjusting pins 40, and an injection mold is used. 1, the temperature of the heating cylinder of the injection molding machine is kept high, and the temperature of the heating cylinder of the injection molding machine is kept at a temperature at which the resin does not cure, for example, a low temperature of 100 ° C. or less. After the mold 1 is clamped, a thermosetting resin having fluidity may be injected into the injection molding die 1 from the nozzle 11 of the injection molding machine.

Then, the thermosetting resin passes through the sprue S, each cold runner section 17, each cold nozzle 11, and each gate 24 from the nozzle 11 of the injection molding machine and is pressed into each product cavity section 29. . At this time, the tip of each flow rate adjusting pin 40 located in the cold runner section 17 appropriately adjusts the flow of the thermosetting resin. If readjustment is required during molding running, the flow rate adjustment pin 40 may be manually moved in and out again. As described above, when the thermosetting resin is pressed into each product cavity portion 29 and solidified, a molded article such as an O-ring or a cap is taken out through a mold opening step and a product taking-out step sequentially.

According to the above configuration, if the flow of the thermosetting resin is appropriately adjusted by the respective flow rate adjusting pins 40, the filling amount of the thermosetting resin in each product cavity portion 29 becomes uniform, so that the injection molding There is no need to disassemble or assemble the mold 1, and it is possible to expect remarkable smoothing, simplification, speeding up, and facilitation of the variation adjustment work. Also,
Products with stable resin internal pressure can be obtained by an easy method, and the lead time until product launch can be expected to be significantly reduced, and molding defects due to unfilling or overfilling can be reliably prevented. .

Also, after the variation adjustment, the flow rate adjusting pin 4
Since the flow of the thermosetting resin can be easily readjusted at 0, it is possible to extremely effectively prevent the charge amount of the molding material in each product cavity 29 from changing.
Further, since it is not always necessary to design the cold runner portions 17 to the position of the gate 24 at the same distance, the degree of freedom of the cavity layout can be remarkably improved. Further, since the flow rate adjusting pins 40 are set on the cold Nanner plate 7 via various stopper mechanisms such as nuts, even if vibrations or the like occur after the flow rate adjustment, there is no displacement.

Further, conventionally, the following problems were considered, but according to the present embodiment, the problems can be easily solved. First, when the variation in the charge amount with respect to the product cavity portion 29 is large, the product cavity portion 29 with a small charge amount is unfilled, and the yield decreases. If the overflow groove (vent burr) is made large to prevent this unfilling and overfilling is performed, the loss of the molding material increases, which greatly deviates from the purpose of the cold runner system. According to the present embodiment, since the flow rate adjusting means 4 exerts a variation suppressing effect, it is possible to reliably prevent the occurrence of unfilling and a decrease in the yield.
Further, the loss of the molding material can be significantly reduced.

Conventionally, when the product cavities 29 have a flashless structure and the charge amounts for the respective product cavities 29 are different, the product cavities 29 that tend to have a large charge amount are thinner than the parting surface. There is a possibility that burrs may occur or a back riding phenomenon may occur. Furthermore, when compared with the product cavity portion 29, which tends to have a small charge amount, the molded product size after demolding increases with an increase in the resin internal pressure, and as a result, the dimensions of the molded product vary, resulting in strict precision molding. There is a possibility that the processing of the product becomes impossible. According to the present embodiment, the product cavity portion 29 that tends to have a large charge amount
Therefore, the amount of charge can be suppressed and the amount of charge can be made the same, so that the occurrence of thin burrs and the phenomenon of back riding can be reliably prevented, and the dimensional accuracy of the molded article can be greatly improved.

FIG. 4 shows a second embodiment of the present invention. In this case, a tunnel-shaped flow passage 41 is formed at the tip of each flow control pin 40A. 41
Is a part of the cold runner section 17, and each flow rate adjusting pin 40A is inserted into the cold runner plate 7 so as to be reciprocally operable from outside. For other parts,
The description is omitted because it is the same as the above embodiment. Also in this embodiment, the same operation and effect as the above embodiment can be expected, and it is clear that the flow rate adjusting pin 40A and the flow passage 41 thereof can be easily processed.

Next, FIG. 5 shows a third embodiment of the present invention. In this case, each flow rate adjusting pin 40B is formed in a circular cross section, and a tunnel-shaped flow passage 41 is provided at its tip.
A, and the flow passage 41A is connected to the cold runner part 1.
7, each flow rate adjusting pin 40B is inserted into the cold runner plate 7 so as to be rotatable from the outside. The other parts are the same as those in the above-described embodiment, and the description is omitted. In this embodiment, the same operation and effect as those of the above embodiment can be expected.
Obviously, B and its flow passage 41A can be easily formed.

In the above-described embodiment, the injection molding machine is merely described. However, various injection molding machines such as a vertical type, a horizontal type, a double type, and a slide type can be used. Further, the cold runner 16 and the cold runner portion 17 can be processed into a semicircular cross section or a trapezoidal cross section. Also,
The cold nozzle 11 and the gate 24 may be a closed nozzle type having a gate shutoff mechanism such as a needle pin. The gate shut-off mechanism may be of a hydraulic type, a pneumatic type, a spring type, or the like. In addition, it is of course possible to appropriately increase or decrease the fixed-side cavity 23, the movable-side cavity 28, and the product cavity 29, or to form the product cavity 29 with a cavity and a core. Therefore, it is also possible to take two pieces, six pieces, eight pieces or more.

Also, a cooling means 12 using a cooling medium such as oil or ethylene glycol may be used. Further, a plurality of cold runner sections 17 and a plurality of cold nozzles 1
1 may be cooled by separate cooling means 12. Further, a heating means 1 having a strip heater, a band heater, and the like.
3 may be used. Also, the flow rate adjusting pins 40 and 40A
-A part of 40B can be bent or the tip part can be branched. Further, the flow control pins 40 and 40A may be obliquely inserted into the respective cold runner portions 17 or the flow control pins 40
It is also possible to set the injection molding die 1 in such a state that the movement direction converting mechanism is interposed between the flow rate adjusting pins 40, 40A and 40B by dividing the flow rate adjusting pins 40A and 40B. Furthermore, each flow rate adjusting pin 40A / 4
The flow passages 41 and 41A can be formed in portions other than the front end portion of 0B.

[0032]

Example 1 Hereinafter, Example 1 using the thermosetting resin injection mold 1 according to the first embodiment will be described using Comparative Example 1. As a molding material, a two-component mixed type liquid silicone rubber (manufactured by Shin-Etsu Chemical Co., Ltd .: KE-1950-50A / B) was used. As an injection molding machine, an in-line screw type molding machine exclusively for liquid silicone rubber having a mold closing pressure of 50 t was used. The temperature of the injection mold 1 is 160
Set to ° C.

Each cold runner part 17 branched into four parts
In the flow rate adjustment, the filling value is set in advance so as to be short-short (unfilled), and the weight after molding is measured while measuring the weight.
The flow rate adjusting pins 40 were inserted and removed so that the weights of the individual product cavities 29 were substantially uniform. Then, the filling amount was set so as to be a charge amount suitable for the capacity of the product cavity portion 29. The curing time of the molding material was 60 seconds from the completion of the injection. After adjusting the flow rate as described above, continuous 10 shot molding was performed. FIG. 12 shows the results of measuring the product weight (unit: g) and product diameter (unit: mm) for each cavity portion. FIG. 6 is a graph plotting the product weight of each cavity, and FIG. 7 is a graph plotting the product diameter of each cavity. FIG. 8 is a graph showing the correlation between the product weight and the product diameter.

Comparative Example 1 The molding material, the molding machine,
Based on the injection mold 1 and the molding conditions, 4
FIG. 13 shows the result of molding in a state where the flow rate adjusting pin 40 is not projected at all into the inside of each cold runner portion 17 branched into a book (state at the time of initial processing without adjustment) in the same unit as FIG. The plotted graphs are shown in FIGS. 9, 10 and 11 in the same manner as described above.

It can be seen from the results of FIGS. 8 to 11 that there is a very high correlation between the product weight and the product diameter (dimension). Further, when the resin flow rate of Comparative Example 1 was not adjusted, Cav. 2> Cav. 3> Cav. 1> C
av. The tendency to increase in the order of 4 was recognized, and the minimum value 3
Variations from 9.54 mm to a maximum of 41.19 mm were measured. The standard deviation of n = 40 is 0.54 m
m. In addition, as a result of inspecting the product molded in Comparative Example 1, a product having a product weight of 14.0 g or less was found to have an unfilled defect, and a product having a product weight of 14.4 g or more generated thin burrs from the parting line. Defects associated with
The product acceptance rate was 60%.

On the other hand, in the first embodiment, by adjusting the resin flow rate in the cold number section, variation in product weight is suppressed as shown in FIG. 6, and the minimum value is 14.08.
The maximum value from g was 14.19 g and the standard deviation was 0.03 g, enabling molding. In addition, the minimum product diameter is 40.05.
mm from the maximum value 40.29mm, standard deviation 0.08m
An extremely high dimensional accuracy of m was obtained, and a product acceptance rate of 100% was obtained in the inspection.

[0037]

As described above, according to the first aspect of the present invention, the time from the production of the mold to the start of the product is shortened, and the charge amount of the molding material is prevented from changing even after the variation is adjusted. There is an effect that can be. Further, the degree of freedom of the cavity layout can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional side view showing an embodiment of a mold for injection molding of a thermosetting resin according to the present invention.

FIG. 2 is an explanatory cross-sectional view showing an embodiment of a thermosetting resin injection mold according to the present invention.

FIG. 3 is an explanatory view showing a flow rate adjusting pin in the embodiment of the thermosetting resin injection molding die according to the present invention.

FIG. 4 is an explanatory view showing a flow rate adjusting pin in a second embodiment of a thermosetting resin injection molding die according to the present invention.

FIG. 5 is an explanatory view showing a flow rate adjusting pin in a third embodiment of a thermosetting resin injection molding die according to the present invention.

FIG. 6 is a graph showing the results of measuring the product weight by cavity in Example 1 of the mold for injection molding of a thermosetting resin according to the present invention.

FIG. 7 is a graph showing the results of measuring the product diameter for each cavity in Example 1 of the mold for injection molding of a thermosetting resin according to the present invention.

FIG. 8 is a graph showing a correlation between a product weight and a product diameter in Example 1 of a thermosetting resin injection mold according to the present invention.

FIG. 9 is a graph showing the results of measurement of product weight by cavity in Comparative Example 1 of the injection-molding mold for a thermosetting resin according to the present invention.

FIG. 10 is a graph showing the results of measuring the product diameter for each cavity in Comparative Example 1 of the thermosetting resin injection mold according to the present invention.

FIG. 11 is a graph showing a correlation between a product weight and a product diameter in Comparative Example 1 of a mold for injection molding of a thermosetting resin according to the present invention.

FIG. 12 is a table showing measurement results of product weight and product diameter in Example 1 of a thermosetting resin injection mold according to the present invention.

FIG. 13 is a table showing measurement results of a product weight and a product diameter in Comparative Example 1 of a mold for injection molding of a thermosetting resin according to the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 injection molding die 2 fixed die 3 movable die 4 flow rate adjusting means 7 cold runner plate (plate) 8 heat insulating plate (heat insulating means) 10 fixed side cavity plate (cavity plate) 11 cold nozzle 12 cooling means 13 Heating means 13A Heating means 16 Cold runner 17 Cold runner part 23 Fixed side cavity 24 Gate 25 Movable side cavity plate 28 Movable side cavity 29 Product cavity part (cavity part) 40 Flow rate adjustment pin 40A Flow rate adjustment pin 40B Flow rate adjustment pin 41 Flow path 41A Flow passage 120 Cooling water passage 121 Cooling jacket 130 Cartridge heater

Claims (5)

[Claims] 1. A fixed mold and a movable mold are clamped,
In a mold for injection molding of a thermosetting resin in which a plurality of cavities between them are filled with a thermosetting resin and molded, a plate and a cavity plate are laminated to constitute the fixed mold. A cold runner is provided inside the plate, the cold runner is divided into a plurality of cold runner portions, and a plurality of cold nozzles for guiding the thermosetting resin from each cold runner portion to each cavity portion are provided inside the cavity plate. And a flow control means for controlling the resistance of each of the cold runner sections to the flow of the thermosetting resin. 2. The mold for injection molding of a thermosetting resin according to claim 1, wherein each of the cavities has a flashless structure. 3. A means for cooling the plurality of cold runner portions and the plurality of cold nozzles, a heating means for the cavity plate, and a heat insulating means interposed between the plate and the cavity plate. The mold for injection molding of a thermosetting resin according to claim 1 or 2, comprising: 4. The flow rate adjusting means includes a plurality of flow rate adjusting pins partially inserted into the plate, and a front end portion of each of the flow rate adjusting pins is moved forward and backward with respect to the inside of the cold runner portion. 4. The mold for injection molding of a thermosetting resin according to claim 1, wherein the mold is made movable and the remaining portions of the respective flow rate adjusting pins are exposed to the outside of the plate to be operable. 5. The flow control means includes a plurality of flow control pins partially inserted into the plate, and a flow passage forming a part of the cold runner portion is provided in a part of each flow control pin. 4. The mold for injection molding of a thermosetting resin according to claim 1, wherein the remaining portions of the respective flow rate adjusting pins are exposed to the outside of the plate so as to be operable.