JP6146910B2 - Injection molding method and injection molding apparatus - Google Patents

Description

  The present invention relates to an injection molding method and an injection molding apparatus for molding various resin molded products.

  Conventionally, as this type of injection molding apparatus, molten resin is injected from a valve gate provided in a movable mold into a cavity formed between a fixed mold and a movable mold. It is known that a molded resin product having a predetermined shape is formed by cooling the resin and solidifying the resin in the cavity (for example, see Patent Document 1).

  The movable mold of the injection molding apparatus is provided with an injection valve having a valve gate at one end, and the injection valve opens and closes the valve gate by a valve pin movable in the axial direction. The valve pin is urged to the valve gate side by a spring, and when molten resin is fed from the extruder side, the valve gate is opened by retreating from the valve gate side against the spring by the pressure of the resin. When the resin is injected into the mold and the resin is filled in the mold and the pressure of the resin decreases, the resin moves to the valve gate side by the spring, and the valve gate is closed.

  By the way, in the said injection molding apparatus, after shape | molding resin in a cavity, a resin molded product is taken out by isolate | separating a movable side metal mold | die from a fixed side metal mold | die, but when a movable side metal mold | die separates from a resin molded product. There is a case where a so-called “string drawing” phenomenon occurs in which the unsolidified resin extends in a thread shape from the valve gate to the resin molded product. When such stringing occurs, there is a problem that the appearance of the resin molded product is impaired and the next molding is also hindered.

  The reason for the occurrence of stringing as described above is that the resin in the molten state remaining in the injection valve after the filling of the resin into the mold is high, so that the resin near the valve gate is not solidified. This is thought to be because the mold is opened. Therefore, if the cooling time of the mold until the mold is opened is lengthened, the occurrence of stringing can be prevented, but the molding cycle becomes longer and the productivity is lowered accordingly. In particular, when mass-producing the same type of resin molded product with a single molding device, the production volume can be changed by changing the time required for a single molding by several seconds to several tens of seconds. It is extremely important to improve the performance.

  Therefore, in order to prevent such stringing from occurring, after filling the resin into the mold, the injection valve or valve gate is cooled to lower the temperature of the resin near the valve gate, thereby reducing the valve One that promotes solidification of the molten resin in the vicinity of the gate is known (for example, see Patent Document 2).

  However, if the injection valve is cooled after filling the mold with resin, the temperature rise near the valve gate at the time of the next injection will be insufficient, so cold slag that solidifies part of the resin in the valve gate. There is a problem that the cold slag is mixed with the resin in the cavity to deteriorate the quality of the resin molded product.

  In addition to preventing stringing after injection and preventing cold slag from occurring during injection, the injection valve is cooled after filling the mold with resin and before the next injection. An apparatus in which an injection valve is heated is known (see, for example, Patent Document 3).

JP-A-5-345334 Japanese Patent Laid-Open No. 10-286843 JP 2004-74803 A

  However, when the injection valve is cooled after the filling of the resin into the mold is completed and the injection valve is heated before the next injection as in the conventional example, the temperature is lowered in the injection valve. Since it takes time to raise the resin again to a sufficient melting temperature, there is a problem that the molding cycle becomes longer and the productivity is lowered accordingly.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an injection molding method and an injection molding capable of shortening a molding cycle without generating stringing or cold slag by a molten resin. To provide an apparatus.

In order to achieve the above object, the present invention injects molten resin from a valve gate provided on one mold side into a cavity formed between a pair of molds facing each other to cool the mold. Then, in the injection molding method of molding a resin molded product by solidifying the resin in the cavity, the other mold extends in a direction perpendicular to the facing direction of one mold and the dimension in the depth direction is wide. A mold in which a recess larger than the dimension in the direction is provided in the cavity so that it passes through the resin injection position, and the entire recess near the resin injection position is formed by a high thermal conductivity portion having a higher thermal conductivity than other portions. The molten resin is injected into the cavity while cooling the high heat conduction part of the other mold to a temperature lower than that of the other part.

In order to achieve the above object, the present invention injects molten resin from a valve gate provided on one mold side into a cavity formed between a pair of molds facing each other, In an injection molding apparatus that molds a resin molded product by cooling the resin and solidifying the resin in the cavity, the other mold extends in a direction perpendicular to the direction facing the one mold and extends in the depth direction. A recess having a dimension larger than the dimension in the width direction is provided in the cavity so as to pass through the resin injection position, and the entire recess near the resin injection position is formed by a high thermal conductivity part having a higher thermal conductivity than the other parts, Cooling means for cooling the high heat conduction part of the other mold to a temperature lower than that of the other part is provided.

As a result, the molten resin is injected into the cavity while the vicinity of the resin injection position in the other mold is cooled to a temperature lower than that of the other part, so that the resin in the cavity near the valve gate after resin injection is injected. Solidification is promoted. In this case, since only the other mold is cooled in the vicinity of the resin injection position, the resin in the valve gate on one mold side is not cooled, and the temperature near the valve gate is maintained at a high temperature. can do. This prevents the occurrence of cold slag due to the temperature drop of the resin during the next injection, and it is not necessary to reheat the resin in the valve gate before the next injection, so that the injection of the molten resin can be started immediately. Is possible. In addition, the other mold is provided with a recess extending in the direction orthogonal to the direction facing the one mold in the cavity so that it passes through the resin injection position. The other position in the cavity is quickly filled through the recess. Furthermore, since the vicinity of the resin injection position in the other mold is formed by a high heat conduction part made of a member having a higher thermal conductivity than the other parts, the resin at the resin injection position is efficiently cooled by the high heat conduction part. The

According to the present invention, since the solidification of the resin in the cavity near the valve gate after the resin injection can be promoted, the stringing by the molten resin is effectively prevented when the valve gate is separated from the resin molded product. be able to. In this case, since the resin in the valve gate on one mold side is not cooled, the temperature in the vicinity of the valve gate can be maintained at a high temperature. Accordingly, it is possible to prevent the occurrence of cold slag due to the temperature drop of the resin at the next injection, and there is an advantage that the quality of the resin molded product is not deteriorated. Further, since it is not necessary to reheat the resin in the valve gate before the next injection, the injection of the molten resin can be started quickly, and the molding cycle can be shortened. Furthermore, since the molten resin injected to the resin injection position can be quickly filled into other positions in the cavity through the recesses, the molding cycle can be shortened by shortening the resin filling time. . In addition, since the resin at the resin injection position can be efficiently cooled by the high heat conduction portion, the cooling effect of the resin at the resin injection position can be further enhanced.

The block diagram of the injection molding apparatus which shows the 1st Embodiment of this invention Front sectional view of main parts of injection molding equipment Side sectional view of the main part of the fixed mold Rear side perspective view of fixed side mold Front side main part perspective view of fixed side mold Front sectional view of the main part of the injection molding device showing the molding process Front sectional view of the main part of the injection molding device showing the molding process Front sectional view of the main part of the injection molding device showing the molding process Configuration diagram of injection molding equipment Configuration diagram of injection molding equipment Main section enlarged view of fixed side mold Side surface sectional drawing of the principal part of the injection molding apparatus which shows the 2nd Embodiment of this invention Side surface sectional drawing of the principal part of the injection molding apparatus which shows the 3rd Embodiment of this invention. Side surface sectional drawing of the principal part of the injection molding apparatus which shows the 4th Embodiment of this invention.

  1 to 11 show a first embodiment of the present invention, which shows an injection molding method and an injection molding apparatus for molding various resin molded products.

  The injection molding apparatus of the present embodiment includes a first molding machine 1 that molds a predetermined resin molded product A, a second molding machine 2 that molds other resin molded products, and first and second molding machines. Cooling tower 3 as cooling liquid cooling means for supplying cooling liquid for mold cooling to 1 and 2 and temperature controller as heating means for raising the cooling liquid supplied to second molding machine 2 to a predetermined temperature 4 and a coolant circuit 5 for circulating the coolant of the cooling tower 3 to the first molding machine 1, the second molding machine 2, and the temperature controller 4.

  The first molding machine 1 includes a fixed mold 10 that is fixed to the molding machine body, a movable mold 20 that is movable with respect to the fixed mold 10, and a fixed mold 10 that is opposed to each other and is movable. An injection valve 30 that injects resin into the cavity 1a formed between the side mold 20 and a cooling fluid that cools the vicinity of the resin injection position on the fixed side mold 10 to a lower temperature than other parts. An air cooler 40 for supplying the cooling air is formed, and a resin molded product A having a plurality of ribs intersecting each other is molded. The movable side mold 20 constitutes one mold, and the fixed side mold 10 constitutes the other mold.

  The stationary mold 10 is disposed so as to face the movable mold 20 in the lateral direction, and a coolant flow path 11 for circulating the coolant of the cooling tower 3 is provided therein. A mold part 12 that forms a part of the cavity 1 a is provided on a surface of the fixed mold 10 facing the movable mold 20, and the mold part 12 is formed in a convex shape with respect to the movable mold 20. ing. The mold part 12 includes a plurality of first recesses 12a extending in the vertical direction (a direction perpendicular to the direction facing the movable mold 20), and a plurality of extensions extending in the front-rear direction (a direction different from the first recess 12a). The ribs of the resin molded product A are formed by the recesses 12a and 12b. The first recesses 12a and the second recesses 12b are provided at intervals in the width direction and intersect so as to form a lattice shape as a whole.

The fixed mold 10 is configured such that resin is injected into a predetermined intersection between the first recess 12a and the second recess 12b, and this intersection (resin injection position P) and its vicinity. Is formed by a high thermal conductivity portion 13 made of a member having a higher thermal conductivity than other portions. In this case, for example, beryllium copper is used as the material of the high heat conducting portion 13. A part of the first recess 12a and a part of the second recess 12b are formed in the high heat conduction part 13 in a block shape so as to intersect each other, and the fixed side mold 10 is integrated with the mold part 12 It is assembled to become. The high heat conducting section 13 is provided with a cooling air flow path 13a through which the cooling air of the air cooler 40 flows, and the cooling air flow path 13a extends from one side surface of one divided member 13a to the other side surface along the second recess 12b. It is formed to extend up to. One end of the cooling air flow path 13 a communicates with one end of an inflow side cooling air flow path 14 provided in the fixed mold 10, and the inflow side cooling air flow path 14 is connected to the outer surface of the fixed mold 10. It communicates with the connection port 15 provided in. The other end of the cooling air flow path 13 a communicates with one end of an outflow side cooling air flow path 16 provided in the fixed mold 10, and the outflow side cooling air flow path 16 is an outer surface of the fixed mold 10. Is open. In this case, the inflow side and outflow side cooling air flow paths 14 and 16 are formed by providing holes that serve as flow paths in the fixed mold 10. The high heat conducting section 13 is composed of two divided members 13b and 13c divided at the center of the second recess 12b, and the divided members 13b and 13c are in close contact with each other so as to conduct heat with each other. 13a is provided on one of the dividing member 13 b.

  The movable mold 20 is disposed so as to face the fixed mold 10 in the lateral direction, and a coolant flow path 21 for circulating the coolant of the cooling tower 3 is provided therein. A mold part 22 that forms another part of the cavity 1 a is provided on the surface of the movable mold 20 facing the fixed mold 10, and the mold part 22 is formed in a concave shape with respect to the fixed mold 10. ing. The movable mold 20 is provided with a valve accommodating section 23 for accommodating the injection valve 30. One end of the valve accommodating section 23 opens into the mold section 22, and the other end is the back surface of the movable mold 20. Is open.

  The injection valve 30 has a valve gate 31 at one end, and is disposed in the valve storage portion 23 of the movable mold 20 so that the valve gate 31 faces the resin injection position P of the fixed mold 10. The injection valve 30 includes a valve body 32 having a valve gate 31 at one end, a valve pin 33 that opens and closes the valve gate 31, and a spring 34 that biases the valve pin 33 toward the valve gate 31. The valve body 32 has a valve gate 31 at the center of one end face, and the one end face is provided so as to face the inside of the mold part 22 and is formed so as to be flush with the inner surface of the mold part 22. A fixing member 35 that engages with the other end side of the valve main body 32 is provided on the back side of the movable mold 20, and the valve main body 32 is fixed in the valve housing portion 23 by the fixing member 35. Further, a support portion 32 a that supports the valve pin 33 so as to be movable in the axial direction is provided in the valve body 32. In the valve body 32, there is provided a resin flow path 32b through which molten resin flowing from the other end of the valve body 32 flows to the valve gate 31. The resin flow path 32b extends from the other end of the valve body 32 to the periphery of the support portion 32a. It is formed so as to extend through to the valve gate 31. The fixing member 35 is provided with a hole 35a having one end communicating with the resin flow path 32b of the valve body 32, and the other end of the hole 35a communicates with a nozzle 50 of an extruder (not shown). The valve pin 33 is configured to open and close the valve gate 31 by one end side formed in a tapered shape, and is supported by the support portion 32a of the valve body 32 so as to be movable in the axial direction. A flange 33a that engages one end of the spring 34 is provided on the center side in the axial direction of the valve pin 33. The flange 33a is engaged with one end of a spring housing portion 32c provided in the support portion 32a, so that the valve pin 33 The movement toward the valve gate 31 is restricted. The spring 34 is a coil spring wound around the center side of the valve pin 33, and is provided in a compressed state between the flange 33a of the valve pin 33 and the other end of the spring accommodating portion 32c.

  The air cooler 40 is a well-known device that generates a high-speed vortex inside by high-pressure air supplied from a compressor and discharges low-temperature air at the center of the vortex as cooling air to the outside. The cooling air of a predetermined temperature (for example, −22 ° C.) is supplied to the cooling air flow path 13 a of the high heat conducting section 13 through the cooling air supply pipe 41 connected to the cooling air supply pipe 15.

  The second molding machine 2 has the same configuration as that of the first molding machine 1 and is set to cool the mold with a coolant having a temperature higher than that of the first molding machine 1.

  The cooling tower 3 is composed of a well-known cooling device that cools the cooling liquid, and cools the cooling liquid that cools the molds 10 and 20 of the first molding machine 1 to a predetermined temperature.

  The temperature controller 4 includes a well-known cooling device that heats the coolant, and heats the coolant that cools the mold of the second molding machine 2 to a predetermined temperature.

  The coolant circuit 5 includes a first pipe 5 a that connects the outflow side of the cooling tower 3 and the inflow side of the first molding machine 1, the outflow side of the first molding machine 1, and the second molding machine 2. A second pipe line 5b connecting the inflow side of the first molding machine 1, a third pipe line 5c connecting the outflow side of the first molding machine 1 and the inflow side of the temperature regulator 4, and the outflow of the temperature regulator 4 A fourth pipe line 5d that connects the second pipe line 5b to the outflow side of the second molding machine 2, and an outflow side of the second molding machine 2 to the inflow side of the cooling tower 3 The sixth pipeline 5e connects the outflow side of the first molding machine 1 of the first pipeline 5a and the inflow side of the second molding machine 2 of the second pipeline 5b. The first pipe 5a is provided with a pump 6.

  The coolant circuit 5 includes a first gate valve 7a that opens and closes the inflow side of the first molding machine 1 in the first pipe line 5a, and a fourth pipe line 5d in the second pipe line 5b. A second gate valve 7b that opens and closes between the branch point and the branch point of the sixth pipeline 5f, a third gate valve 7c that opens and closes the third pipeline 5c, and a fourth pipeline 5d A fourth gate valve 7d that opens and closes and a fifth gate valve 7e that opens and closes the sixth pipeline 5f are provided.

  In the injection molding apparatus configured as described above, when the resin molding A is molded by the first molding machine 1, the fixed mold 10 and the movable mold 20 are clamped as shown in FIG. As shown in FIG. 6, the cooling air of the air cooler 40 is circulated through the cooling air flow path 13 a of the fixed mold 10. Thereafter, the molten resin B is injected into the cavity 1a between the molds 10 and 20 while flowing the cooling air through the cooling air flow path 13a, and the molten resin B is filled into the cavity 1a. That is, when the molten resin B flows from the nozzle 50 of the extruder into the resin flow path 32b of the injection valve 30, the valve pin 33 moves backward from the valve gate 31 against the spring 34 by the pressure of the molten resin B. The valve gate 31 is opened and the molten resin B is injected into the cavity 1a. At that time, since the molten resin B is injected to the resin injection position P where the first recess 12a and the second recess 12b intersect, the molten resin B passes through the first recess 12a and the second recess 12b. The other position in the cavity 1a is quickly filled through.

  When the molten resin B is filled in the cavity 1a and the pressure of the resin in the resin flow path 32b decreases, the valve pin 33 moves to the valve gate 31 side by the spring 34 as shown in FIG. Closed by. Then, after each metal mold | die 10 and 20 is cooled with the cooling fluid which distribute | circulates the cooling fluid flow paths 11 and 21, and the resin in the cavity 1a solidifies, the movable mold 20 is fixed to the fixed metal mold as shown in FIG. The movable mold 20 is separated from the resin molded product A by moving in a direction away from the mold 10. At that time, the resin in the vicinity of the valve gate 31 (resin at the intersection of the first recess 12a and the second recess 12b) passes through the high heat conduction section 13 by the cooling air of the air cooler 40 flowing through the cooling air flow path 13a. Thus, since the resin is cooled to a temperature lower than that of the other part of the fixed mold 10, solidification of the resin in the cavity 1 a near the valve gate 31 is promoted, and the valve gate 31 is separated from the resin molded product A. Stringing with molten resin is prevented.

  In the resin molding, the temperature of the cooling liquid for cooling the mold is usually about 18 ° C. When the resin molded product A is molded by the first molding machine 1, the cooling of the molds 10 and 20 is performed. If the temperature of the coolant flowing through the liquid flow paths 11 and 21 is set to a temperature lower than the normal temperature, the resin in the cavity 1a in the vicinity of the valve gate 31 can be cooled to a lower temperature, and the stringing prevention effect Can be increased. In this case, the temperature of the cooling liquid cooled in the cooling tower 3 may be set to a low first temperature T1 (for example, 5 ° C.) for cooling the mold of the first molding machine 1, but other types of resins are used. The coolant temperature for cooling the mold of the second molding machine 2 for molding the molded product is set to a second temperature T2 (for example, 18 ° C.) higher than the first temperature T1.

  Therefore, as shown in FIG. 1, the first to fourth gate valves 7a to 7d of the coolant circuit 5 are opened, and the fifth gate valve 7e is closed. As a result, the coolant at the first temperature T1 flowing out of the cooling tower 3 (solid arrow in the figure) flows to the first molding machine 1 via the first pipe line 5a, and the first molding machine 1 The mold is cooled by the coolant at the first temperature T1. Next, the coolant that has flowed out of the first molding machine 1 flows to the temperature regulator 4 through the third pipe 5c, and is heated to the second temperature T2 by the temperature regulator 4 to obtain the second temperature. The T2 coolant (broken arrow in the figure) flows to the second molding machine 2 through the fourth pipe line 5d and the second pipe line 5b. As a result, the mold of the second molding machine 2 is cooled by the coolant at the second temperature T2.

  Next, without using the first molding machine 1, the resin molding product A is molded by the second molding machine 2 using the molds 10, 20 of the first molding machine 1 in the second molding machine 2. In this case, as shown in FIG. 9, the fifth gate valve 7e of the coolant circuit 5 is opened, and the first and second gate valves 7a and 7b are closed. As a result, the coolant at the first temperature T1 flowing out of the cooling tower 3 (solid arrow in the figure) flows only to the second molding machine 2 via the first pipe line 5a and the sixth pipe line 5f. The mold of the second molding machine 2 is cooled by the coolant having the first temperature T1.

  Further, when the resin molded product A is molded by both the first molding machine 1 and the second molding machine 2, the first, second and fifth gate valves of the coolant circuit 5 as shown in FIG. 7a, 7b, and 7e are opened, and the third and fourth gate valves 7c and 7d are closed. As a result, the coolant at the first temperature T1 flowing out from the cooling tower 3 (solid arrow in the figure) is diverted to the first pipe line 5a and the sixth pipe line 5f. Each of the molding machines 2 is distributed. As a result, the mold of the first molding machine 1 and the mold of the second molding machine 2 are cooled by the coolant at the first temperature T1. In the case where a resin molded product formed by cooling the mold at the second temperature T2 is formed by both the first molding machine 1 and the second molding machine 2, the cooling cooled by the cooling tower 3 is performed. The temperature of the liquid may be set to the second temperature T2.

  Thus, according to the present embodiment, the molten resin is injected into the cavity 1a while cooling the vicinity of the resin injection position P in the fixed mold 10 to a temperature lower than that of the other portions. Solidification of the resin in the cavity 1a in the vicinity of the valve gate 31 after injection can be promoted, and stringing by the molten resin when the valve gate 31 is separated from the resin molded product A can be effectively prevented.

  In this case, since only the fixed mold 10 is cooled in the vicinity of the resin injection position P, the resin in the injection valve 30 on the movable mold 20 side is not cooled, and the temperature in the vicinity of the valve gate 31 is set. High temperature can be maintained. Accordingly, it is possible to prevent the occurrence of cold slag due to the temperature drop of the resin at the next injection, and there is an advantage that the quality of the resin molded product is not deteriorated. Moreover, since it is not necessary to reheat the resin in the injection valve 30 before the next injection, the injection of the molten resin can be started quickly, and the molding cycle can be shortened.

  In addition, the cooling air is circulated by the air cooler 40 through the cooling air flow path 13a that can exchange heat with the portion in the fixed mold 10 near the resin injection position P, so that the vicinity of the resin injection position P in the fixed mold 10 Since this portion is cooled, the resin at the resin injection position P can be efficiently cooled by heat conduction from the cooling air flow path 13a.

  In this case, since the vicinity of the resin injection position P in the fixed-side mold 10 is formed by the high thermal conductive portion 13 made of a member having a higher thermal conductivity than other portions, the cooling air and the resin injection in the cooling air flow path 13a are formed. It is possible to efficiently exchange heat with the resin at the position P via the high heat conducting section 13, and the cooling effect by the cooling air in the cooling air flow path 13a can be further enhanced.

  The fixed mold 10 has a first recess 12a extending in a direction orthogonal to the facing direction of the movable mold 20, and a second recess 12b extending in a direction different from the first recess 12a. Since it is provided in the cavity 1a so as to pass through the resin injection position P, the molten resin injected into the resin injection position P can be quickly passed through the first recess 12a and the second recess 12b to the other in the cavity 1a. The molding cycle can also be shortened by shortening the resin filling time. When the recesses 12a and 12b are provided at the resin injection position P, the resin filling volume at the resin injection position P is reduced by the recesses 12a and 12b, compared to when the recesses 12a and 12b are not provided at the resin injection position P. Therefore, the heat capacity increases correspondingly, and the temperature drop of the resin near the valve gate 31 is delayed, but in this embodiment, the cooling air of the air cooler 40 causes the intersection of the recesses 12a and 12b to be more than the other parts. Since cooling is performed at a low temperature, the temperature of the resin at the intersection of the recesses 12a and 12b can be quickly reduced. Thereby, even if it injects resin to the position of recessed part 12a, 12b, there exists an advantage that filling time can be shortened, without impairing the stringing prevention effect.

  Further, since the first concave portion 12a and the first concave portion 12a are provided in the cavity 1a so as to cross each other at the resin injection position P, the molten resin injected to the resin injection position P can be used as the first concave portion. It is possible to simultaneously fill in the direction in which 12a extends and the direction in which the second recess 12b extends, and the resin filling time can be further shortened.

  Further, temperature control is performed to heat the coolant flowing into the mold of the second molding machine 2 to a second temperature T2 higher than the first temperature T1 of the coolant flowing into the mold of the first molding machine 1. Since the apparatus 4 is provided, when the resin molded product A is molded by the first molding machine 1, the temperature of the cooling liquid for cooling the mold of the first molding machine 1 is set to a low temperature, so that the valve The resin in the cavity 1a in the vicinity of the gate 31 can be cooled to a lower temperature to enhance the stringing prevention effect. At that time, the second molding machine 2 for cooling the mold at the second temperature T2 higher than the first temperature T1 of the coolant flowing into the mold of the first molding machine 1 is used as the first molding machine 1. Since it can be used at the same time, it is extremely advantageous for a factory for molding a plurality of types of resin molded products having different mold cooling temperatures.

  In the above-described embodiment, the inflow side cooling air flow path 14 of the cooling air flow path 13a is formed by providing the fixed mold 10 with holes serving as flow paths. As shown, if the inflow side cooling air flow path 14 is formed by a heat insulating member 14 a having heat insulation properties with respect to the fixed mold 10, the cooling air in the inflow side cooling air flow path 14 and the fixed mold 10 are Heat conduction can be reduced. Thereby, the temperature rise of the cooling air before reaching the cooling air flow path 13a can be suppressed, and the cooling effect by the cooling air of the cooling air flow path 13a can be further enhanced. In this case, for example, the inner peripheral surface of the hole for the inflow side cooling air channel 14 provided in the fixed mold 10 is covered with a heat insulating resin having a higher melting temperature than the fixed mold 10, or By embedding a pipe made of such a resin in the hole, the heat insulating member 14a can be formed.

  Moreover, in the said embodiment, since only a part of the stationary mold 10 is illustrated, only one resin injection position P in the stationary mold 10 is illustrated, but there are a plurality of resin injection positions P. Are provided for each resin injection position P, such as a high heat conduction portion 13 and a cooling air flow path 13a.

  Furthermore, although the said embodiment showed what each provided the 1st shaping | molding machine 1 and the 2nd shaping | molding machine 2 one each, you may be provided with several each.

  In the above embodiment, the cooling air flow path 13a as the cooling flow path is configured to distribute the cooling air of the air cooler 40. However, the cooling means is not limited to this. You may make it distribute | circulate the low-temperature refrigerant | coolant of a freezing circuit as a fluid for use.

  Furthermore, in the said embodiment, the 1st recessed part 12a extended in the direction orthogonal to the opposing direction with the movable mold 20 at the fixed side metal mold | die 10, and the 2nd extended in the direction different from the 1st recessed part 12a. Although what was provided in the cavity 1a so that the recessed part 12b might cross | intersect at the resin injection position P was shown, like the 2nd Embodiment shown in FIG. In the case where only the first concave portion 12 a extending in the direction orthogonal to the facing direction with respect to 20 is provided, the first concave portion 12 a may be provided so as to pass through the resin injection position P. Further, as in the third embodiment shown in FIG. 13, the first concave portion 12a and the second concave portion 12b intersect in a T shape at the resin injection position P, or the fourth embodiment shown in FIG. As described above, the first recess 12a and the second recess 12b may intersect at the resin injection position P in an L shape.

  DESCRIPTION OF SYMBOLS 1 ... 1st molding machine, 2 ... 1st molding machine, 3 ... Cooling tower, 4 ... Temperature controller, 5 ... Coolant circuit, 10 ... Fixed side metal mold | die, 12a ... 1st recessed part, 12b ... 1st 2 concave portions, 13 ... high heat conduction portion, 13a ... cooling air flow path, 14 ... inflow side cooling air flow path, 20 ... movable side mold, 30 ... injection valve, 31 ... valve gate, 40 ... air cooler, A ... resin Molded product, B: molten resin, P: resin injection position.

Claims (10)

By injecting molten resin from a valve gate provided on one mold side into a cavity formed between a pair of molds facing each other, and cooling the mold to solidify the resin in the cavity In an injection molding method for molding a resin molded product,
As the other mold, a recess extending in a direction perpendicular to the direction facing the one mold and having a depth dimension larger than the width dimension is provided in the cavity so as to pass through the resin injection position. Using a mold in which the entire recess near the resin injection position is formed by a high thermal conductivity part having a higher thermal conductivity than other parts,
An injection molding method characterized by injecting molten resin into a cavity while cooling a high heat conduction part of the other mold to a temperature lower than that of other parts. As the other mold, a recess extending in a direction orthogonal to the facing direction of one mold and having a depth dimension larger than a width dimension;
A mold provided in the cavity is used so that it extends in a different direction from the recess and has another recess whose dimension in the depth direction is larger than the dimension in the width direction at the resin injection position. The injection molding method according to claim 1 . A portion of the other mold near the resin injection position is cooled by circulating a cooling fluid through a cooling flow path that can exchange heat with the portion near the resin injection position of the other mold. The injection molding method according to claim 1 or 2 . Uses a gas cooler that generates a high-speed vortex inside by high-pressure air and discharges the low-temperature air at the center of the vortex to the cooling channel as the cooling fluid
The injection molding method according to claim 3. By injecting molten resin from a valve gate provided on one mold side into a cavity formed between a pair of molds facing each other, and cooling the mold to solidify the resin in the cavity In injection molding equipment for molding resin molded products,
The other mold is provided with a recess extending in a direction orthogonal to the direction facing the one mold and having a depth dimension larger than the width dimension in the cavity so as to pass through the resin injection position. In addition, the entire recess near the resin injection position is formed by a high thermal conductivity part having a higher thermal conductivity than other parts,
An injection molding apparatus comprising a cooling means for cooling the high heat conduction part of the other mold to a temperature lower than that of the other part. The other mold has a recess extending in a direction orthogonal to the direction facing the one mold and having a depth dimension larger than a width dimension ;
According to claim 5, wherein the other of the recess is greater than the dimension of the recess and different extending in a direction and a depth direction dimension width direction, characterized in that it is provided in the cavity so as to intersect at a resin injection position Injection molding equipment. Said cooling means, the other in the vicinity of the resin injection position in the mold part and the heat-exchangeable cooling the cooling flow path of the fluid according to claim 5 or 6, characterized in that which is configured to flow the Injection molding equipment. In the other mold, an inflow side flow path for allowing the fluid to flow into the cooling flow path is provided,
8. The injection molding apparatus according to claim 7, wherein the inflow side flow path is formed by a member having a heat insulating property with respect to the other mold. A gas cooler that generates a high-speed vortex inside by high-pressure air and discharges the low-temperature air at the center of the vortex as a cooling fluid to the cooling flow path is provided.
The injection molding apparatus according to claim 7 or 8, wherein At least one first molding machine for molding the resin molded article;
At least one second molding machine for molding other resin molded products;
A coolant circuit for circulating the coolant through the molds of the first and second molding machines;
A coolant cooling means for cooling the coolant in the coolant circuit to a predetermined first temperature;
And a heating means for heating the coolant flowing into the mold of the second molding machine to a predetermined second temperature higher than the coolant flowing into the mold of the first molding machine. The injection molding apparatus according to claim 5, 6, 7, 8 or 9 .

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