WO2019151343A1

WO2019151343A1 - Mold device for injection molding and method for producing molded article using mold device for injection molding

Info

Publication number: WO2019151343A1
Application number: PCT/JP2019/003225
Authority: WO
Inventors: 雅憲森本; 田中　健一; 阿部　諭; 内野々　良幸; 渡辺　真也
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2018-01-31
Filing date: 2019-01-30
Publication date: 2019-08-08
Also published as: JPWO2019151343A1; JP6928819B2

Abstract

An embodiment of the present invention provides a mold device for injection molding, the device including a hot raw-resin flow path that is connected to a mold cavity through a gate. A heat transfer control unit is provided at least in a region that is proximate to the gate.

Description

INJECTION MOLD DEVICE AND METHOD FOR MANUFACTURING MOLDED ARTICLE USING INJECTION MOLD DEVICE

The present invention relates to an injection mold apparatus and a method for producing a molded product using the injection mold apparatus. More specifically, the present invention relates to an injection mold apparatus having a hot mold material resin flow path connected to a mold cavity via a gate, and an injection molded product using the injection mold apparatus It relates to the manufacturing method.

One of the technologies that has supported the Japanese manufacturing industry is molding technology using molds. Examples of such a molding technique include a pressure molding method, an injection molding method, and an extrusion molding method. Among these molding methods, the injection molding method is a method of obtaining a molded product from a raw material resin using an injection molding die apparatus.

Specifically, in the injection molding method, a molded product is manufactured through the following steps. (1) A step of supplying a raw material resin to a raw material resin flow path constituted by (i) sprue or (ii) a sprue and a runner and connected to a mold cavity via a gate.
(2) A step of continuously supplying the raw material resin and filling / holding the raw material resin in the mold cavity.
(3) Cooling process of the raw material resin in the mold cavity.

Here, the final molded product is usually obtained from raw material resin located in the mold cavity. Therefore, the resin part obtained by cooling the raw material resin located in the raw material resin flow path composed of (i) sprue or (ii) sprue and runner does not directly contribute as a component of the final molded product. Therefore, in order to maintain the molten state without cooling the raw material resin located in the raw material resin flow path from the viewpoint of efficient use of the raw material resin, etc., the hot type raw material resin connected to the mold cavity through the gate A flow path may be used (see Patent Document 1). Patent Document 1 shows that a temperature control medium path is provided along the axis of the raw material resin flow path. By providing the temperature control medium path, the raw material resin flow path can be maintained at a high temperature, whereby the raw material resin flow path can function as a hot-type raw material resin flow path.

Japanese Patent Laid-Open No. 2002-210895

Here, the inventors of the present application have newly found that the following problems can occur when the temperature control medium path is provided along the axis of the hot type resin flow path.

Specifically, as described above, the hot-type raw material resin flow path can maintain a molten state without cooling the raw material resin located in the flow path. The hot mold material resin flow path is connected to the mold cavity via a gate. Therefore, when the molten state of the raw material resin in the hot mold material resin flow path is maintained, the heat of the molten raw material resin is changed from the hot mold raw material resin flow path side to the injection mold side, particularly near the gate of the injection mold. May be transmitted to the side. Therefore, when carrying out the cooling process of the raw material resin in the mold cavity, the raw material resin located in a local part in the mold cavity near the gate due to heat transfer to the vicinity of the gate of the injection mold However, there is a possibility that the temperature becomes higher than that of the raw material resin located in the other part in the mold cavity. As a result, the raw material resin located in the local part in the mold cavity near the gate is relatively difficult to cool compared with the raw material resin located in the other part in the mold cavity. There is a possibility that a highly accurate molded product cannot be suitably obtained as a whole.

The present invention has been made in view of such circumstances. That is, an object of the present invention is to use an injection mold apparatus and an injection mold apparatus capable of suitably obtaining a high-precision molded product as a whole even when a hot mold material resin flow path is used. It is to provide a method for manufacturing a molded product.

In order to achieve the above object, in one embodiment of the present invention,
An injection mold apparatus,
A hot mold material resin flow path connected to the mold cavity via the gate,
There is provided an injection molding die apparatus having a heat transfer control unit at least in a region near the gate.

In order to achieve the above object, in one embodiment of the present invention,
A method for producing an injection-molded article using an injection mold apparatus,
The injection mold apparatus comprises a hot mold material resin flow path connected to a mold cavity through a gate, and has a heat transfer control unit at least in the immediate region of the gate,
A method is provided for providing a molten raw resin through the hot mold raw resin flow path into the mold cavity.

According to one embodiment of the present invention, even when a hot-type raw material resin flow path is used, it is possible to suitably obtain a highly accurate molded product as a whole.

Sectional drawing which showed typically the injection mold apparatus which concerns on one Embodiment of this invention Sectional drawing which showed typically the injection mold apparatus which concerns on another one Embodiment of this invention Sectional drawing which showed typically the injection molding die apparatus which concerns on another one Embodiment of this invention. Sectional drawing which showed typically the injection molding die apparatus which concerns on another one Embodiment of this invention. Sectional drawing which showed typically the injection molding die apparatus which concerns on another one Embodiment of this invention. Sectional drawing which showed typically the injection molding die apparatus which concerns on another one Embodiment of this invention. Cross-sectional views schematically showing the process aspect of stereolithography combined processing in which the powder sintering lamination method is performed (FIG. 7 (a): at the time of forming the powder layer, FIG. 7 (b): at the time of forming the solidified layer, FIG. c): During lamination

Hereinafter, an injection mold apparatus according to an embodiment of the present invention will be described with reference to the drawings. The forms and dimensions of the various elements in the drawings are merely examples, and do not reflect actual forms and dimensions.

(Technical idea of the present invention)
First, prior to the description of an injection molding die apparatus according to an embodiment of the present invention, the technical idea of the present invention will be described.

The inventors of the present application have intensively studied technical measures for enabling a highly accurate molded product to be suitably obtained even when a hot-type raw material resin flow path is used. More specifically, the raw material resin located in the local portion in the mold cavity near the gate caused by the heat transfer of the molten raw material resin from the hot mold material resin flow path side to the vicinity of the gate of the injection mold is Measures for suppressing the state of being relatively difficult to cool than the raw material resin located in other portions have been intensively studied.

Therefore, in order to realize such a deterrent measure, the inventors of the present application “a heat transfer control unit capable of controlling heat transfer in at least the immediate region 100A of the gate G compared to other regions 100B other than the immediate region 100A of the gate G”. The technical idea of “providing 20” was newly found (see FIG. 1).

As used herein, “the closest region 100A of the gate G” refers to a predetermined injection molding die closest to the gate G located at the boundary between the mold cavity 30 and the hot mold material resin flow path 10. Refers to an area. As used herein, the term “hot-type raw material resin flow path 10” refers to a raw material resin flow path that is heated and held in a broad sense, and in a narrow sense refers to only a heated and held sprue or a heated and held sprue and runner. . The “heat transfer control unit 20” in the present specification refers to a region where heat transfer can be controlled with an injection mold.

According to such a technical idea, due to the presence of the heat transfer control unit 20 in the region 100A closest to the gate, the injection mold 100 from the hot mold material resin flow channel 10 side connected to the mold cavity 30 through the gate G is provided. The heat transfer of the molten raw material resin R in the hot type raw material resin flow channel 10 (particularly, the molten raw material resin R ₁ in the hot type raw material resin flow channel 10 located in the vicinity of the gate G) to the region 100A closest to the gate G of It becomes possible to do. The heat transfer control of the heat transfer control unit 20, the heat of the gate G immediate vicinity region 100A of the injection mold 100 due to the melting heat of the molten starting resin R ₁ in the vicinity of the gate G of the hot feedstock resin passage 10 It is possible to suitably control the remaining. Thus, it is possible to suppress the heat transfer from the gate G immediate vicinity region 100A of the injection mold 100 into the molten material resin R ₃ is located in the mold cavity 30 located in the vicinity the gate G.

Further, the molten raw material resin R ₃ located in the region near the gate G in the mold cavity 30 is located in another region in the mold cavity 30 due to the proximal arrangement of the hot mold raw material resin flow path 10. likely to become hotter than the molten starting resin R _4. Therefore, the heat of the molten raw material resin R ₃ at a higher temperature located in the local portion 31 near the gate G in the mold cavity 30 remains in the filling and pressure holding process of the molten raw material resin into the mold cavity. obtain. In this regard, when the heat transfer control unit 20 exists in the region 100 A closest to the gate, the molten raw material resin R located in the local portion 31 near the gate G in the mold cavity 30 by the heat transfer control by the heat transfer unit control unit 20. Therefore, it is possible to suitably suppress and control that the heat energy in the high temperature state ₃ is transmitted to the region 100A closest to the gate G. Further, when the heat transfer control unit 20 exists in the region 100 A closest to the gate, the molten raw material resin R ₃ located in the local portion 31 near the gate G in the mold cavity 30 is controlled by the heat transfer control by the heat transfer unit control unit 20. Residual heat in a high temperature state can be suppressed. Thus, the thermal residual high temperature of the molten material resin R ₃ is located in the local part 31 of the gate G near the mold cavity 30 it is possible to suppress to continue.

From the above, the molten raw material resin R ₃ located in the local portion 31 near the gate G in the mold cavity 30 has a higher temperature than the molten raw material resin R ₄ located in other portions in the mold cavity 30. This can be suppressed.

Thus, in the cooling step of the molten material resin mold cavity 30, the molten material resin R ₃ is located in the local part 31 of the gate G near the mold cavity 30, the other portions of the mold cavity 30 position and cooling of the molten starting resin R ₄ it is possible to carry out substantially at the same cooling rate. That is, in the cooling step of the molten raw material resin R in the mold cavity 30, the molten raw material resin to a molten raw material resin R ₃ located in the vicinity of the gate G of the mold cavity 30 is located in the other part of the mold cavity 30 it is possible to suitably suppress the than R ₄ hardly cooled. Therefore, finally, it is possible to suitably obtain a highly accurate molded product as a whole.

(Configuration of injection molding die device)
Hereinafter, a configuration of an injection mold apparatus 200 according to an embodiment of the present invention will be described (see FIG. 1).

An injection mold apparatus 200 according to an embodiment of the present invention is an injection mold 100 (comprising a core side and a cavity side), and for supplying a molten raw material resin into the injection mold 100. This includes a hot mold sprue member 50 provided therein with a hot mold material resin flow path 10 (corresponding to a sprue). In one embodiment, the hot mold sprue member 50 is configured to contact the injection mold 100 so that the hot mold material resin flow path 10 is directly connected to the gate G. The hot-type sprue member 50 usually has a shape in which the diameter of the tip 50A gradually decreases. That is, the contact portion between the tip 50A of the hot mold sprue member 50 and the injection mold 100 can have an inclined surface (see FIG. 1), more specifically, a step surface. The configuration of the hot mold sprue member 50 is not limited to the configuration in contact with the injection mold 100 so that the hot mold material resin flow path 10 is directly connected to the gate G. For example, in one embodiment, the hot mold sprue member 50 may be configured to connect to the injection mold 100 through a runner. In this case, it is confirmed that the hot mold material resin flow path 10 is composed of a sprue provided in the hot mold sprue member 50 and a runner provided in the injection mold. . The “tip 50A of the hot-type sprue member 50” as used in this specification means that the molten raw material resin (on the mold cavity 30 side) from the opening provided at the bottom (or the bottom or top) of the hot-type sprue member 50. It is not the point that flows out to the runner side). The “tip 50A of the hot mold sprue member 50” as used herein refers to the outside of the hot mold sprue member 50 that is closest to the bottom of the hot mold sprue member 50 and can contact the inner surface of the injection mold 100. The side surface portion, that is, the “tip side outer surface” is indicated. In addition, the “local portion 31 near the gate G in the mold cavity 30” in this specification means, in a broad sense, the “inlet portion to which molten raw material resin is supplied” in the mold cavity and the inlet portion. This refers to a portion along the surface of the mold cavity 30 to be formed (see FIG. 1).

Hereinafter, a description will be given based on the case where the hot type raw material resin flow path 10 (corresponding to the sprue) in the hot type sprue member 50 is directly connected to the gate G. In this case, the tip 50A of the hot mold sprue member 50 is in direct contact with the injection mold 100 at the gate G. This means that the mold cavity 30 exists near the tip of the hot mold sprue member 50 with the gate G interposed therebetween. If the mold cavity 30 exists in the vicinity of the tip of the hot mold sprue member 50, the following technical problems may occur in the cooling process of the molten raw material resin filled in the mold cavity 30. Specifically, first, the heat of the molten raw material resin flowing through the hot type raw material resin flow path 10 (corresponding to the sprue) passes through the contact portion 60 between the tip 50A of the hot type sprue member 50 and the injection mold 100. Thus, it can be transmitted to the region 100A closest to the gate G of the injection mold 100. Next, the heat of the molten raw material resin flowing through the hot type raw material resin flow path 10 (corresponding to the sprue) is located in the vicinity of the tip of the hot type sprue member 50 through a local portion near the gate G of the injection mold 100. Can be transmitted to the mold cavity 30.

Therefore, in the case where the hot-type raw material resin flow path 10 (corresponding to the sprue) in the hot-type sprue member 50 is directly connected to the gate G, the heat transfer control unit 20 determines that “the tip 50A of the hot-type sprue member 50 and the injection 50 It can be positioned in the region 100A proximate to the gate G of the injection mold 100 "located between the contact portion 60" with the mold 100 and the "mold cavity 30". When the heat transfer control unit 20 exists in the immediate area 100A, the heat of the molten raw material resin flowing through the hot type resin flow path 10 (corresponding to the sprue) is transmitted to the immediate area 100A of the gate G through the contact portion 60. Can be suppressed. More specifically, it is possible to heat the molten raw material resin R ₁ hot feedstock resin flow passage 10 positioned near the gate G is suppressed from being transmitted to the gate G immediate vicinity region 100A. Further, when the heat transfer control unit 20 to the gate G immediate vicinity region 100A exist, molten material resin R ₃ thermal gate G immediate vicinity region 100A located in a local portion 31 of the gate G near the mold cavity 30 (in FIG. 1 It is possible to suppress the transmission to the dotted line encircled part). As described above, for example, when the diameter of the tip 50A of the hot mold sprue member 50 is gradually reduced, the contact portion 60 between the tip 50A of the hot mold sprue member and the injection mold 100 has an inclined surface. (See FIG. 1). In this case, “the nearest region 100A of the gate G” is a region formed between the contact portion 60 having an inclined surface and the formation surface of the mold cavity 30 facing the contact portion 60 (dotted line in FIG. 1). It corresponds to the enclosed part).

By heat transfer control by the heat transfer control unit 20, the heat of the molten raw material resin R ₁ located in the vicinity of the gate G in the hot type raw material resin flow path 10 (corresponding to the sprue) / the vicinity of the gate G in the mold cavity 30. Due to the heat of fusion of the molten raw material resin R ₃ located in the local portion 31, it is possible to suitably suppress and control the heat remaining in the region 100 A closest to the gate G between the contact portion 60 and the mold cavity 30. Become. Due to the suppression of the remaining heat, the molten raw material located in the local portion 31 in the mold cavity 30 located in the vicinity of the tip of the hot mold sprue member 50 from the region 100A closest to the gate G between the contact portion 60 and the mold cavity 30. it is possible to suppress heat transfer to the resin R _3. Thereby, in the cooling process of the molten raw material resin filled in the mold cavity 30, the hot mold sprue member 50 is brought into the vicinity of the tip of the hot mold sprue member 50 via the region 100 A closest to the gate G between the contact portion 60 and the mold cavity 30. It is possible to suitably prevent the melting heat from being transmitted to the mold cavity 30 located. Thereby, in the cooling process of the molten raw material resin R in the mold cavity 30, the molten raw material resin R ₃ in the local portion 31 in the mold cavity 30 located near the tip of the hot mold sprue member 50 is in the mold cavity 30. it is possible to suitably suppress also difficult to cool than the melting material resin R ₄ other portion 32 of the.

In addition, it is preferable that the “heat transfer control unit 20” used in the present invention is realized in the following manner. Specifically, the “heat transfer control unit 20” (i) provides a cooling medium path to the region 100 A closest to the gate in the injection mold 100, and (ii) proximate to the gate in the injection mold 100. This may be realized by providing a local low density portion in the region 100A and / or (iii) providing a low heat transfer film on the surface of the injection mold 100 in the region 100A closest to the gate.

(I) Heat transfer control unit 20: In one aspect of the cooling medium path , the “heat transfer control unit 20” is preferably a cooling medium path 20A provided at least to the region 100A closest to the gate in the injection mold 100. (See FIG. 2).

The “cooling medium path” in this specification is a hollow flow path for flowing the cooling medium, and the melting heat of the molten raw material resin flowing in the hot type raw material resin flow path 10 is the gate of the injection mold 100. The flow path for suppressing the transmission to the region closest to G and reducing the thermal energy of the raw material resin in the mold cavity near the gate G is shown. “Cooling medium” refers to a medium that flows through the cooling medium path, such as cooling liquid (water, oil), cooling gas (air, inert gas), cooling solid, cooling gas-cooling liquid mixed phase, or This refers to a cooled solid-cooled liquid mixed phase.

In this case, the cooling medium path 20 A as the “heat transfer control unit 20” can be positioned in the immediate vicinity of the gate G. Due to the presence of the cooling medium path 20A, the melting heat energy of the molten raw material resin flowing through the hot type raw material resin flow path 10 is reduced by the cooling heat energy of the cooling medium flowing through the cooling medium path 20A located in the immediate region of the gate G. . Moreover, the presence of such a coolant passage 20A, the immediate vicinity region 100A of the molten material resin R ₃ of thermal energy injection mold gate G of the localized portion 31 of the mold cavity 30 located in the vicinity of the gate G It is reduced by the cooling heat energy of the cooling medium flowing in the cooling medium path 20A located. Note that the cooling medium path 20 A as the “heat transfer control unit 20” may have a double structure in the immediate region of the gate G. In this case, the cooling heat energy of the cooling medium flowing through the cooling medium path 20A located in the immediate vicinity of the gate G can be relatively increased as compared with the case of adopting a normal single structure. Therefore, due to the adoption of such a double structure, “the melting thermal energy of the molten raw material resin flowing in the hot type raw material resin flow path 10” and “the local area in the mold cavity 30 located in the vicinity of the gate G”. The thermal energy of the part of the molten raw material resin can be reduced more effectively and effectively. Further, for example, when the diameter of the tip 50A of the hot mold sprue member 50 is gradually reduced, the contact portion 60 between the tip 50A of the hot mold sprue member and the injection mold 100 has an inclined surface ( (See FIG. 2). In this case, at least a part of the cooling medium path 20 A as the “heat transfer control unit 20” is formed between the contact portion 60 having an inclined surface and the forming surface of the mold cavity 30 facing the contact portion 60. It will be formed in the area. In this case, due to the presence of the cooling medium path 20A, the melting heat energy of the molten raw material resin flowing in the hot type raw material resin flow path 10 is the contact surface 60 having the inclined surface and the formation surface of the mold cavity 30 facing the contact portion 60 Is reduced by the cooling heat energy of the cooling medium flowing in the cooling medium path 20A located in the region formed between the two. Moreover, the presence of the cooling medium passage 20A, facing the contact portion 60 and the contact portion 60 of the thermal energy of the molten material resin R ₃ of localized portion 31 of the mold cavity 30 located in the vicinity of the gate G has an inclined surface It is reduced by the cooling heat energy of the cooling medium flowing in the cooling medium path 20A located in the region 100A closest to the gate G formed between the formation surface of the mold cavity 30.

As described above, the melting thermal energy of the molten raw resin in the hot mold raw resin flow path 10 / the melting thermal energy of the molten raw resin located in the region near the gate G in the mold cavity 30 is transferred to the region 100A closest to the gate G. It is reduced by the cooling heat energy of the cooling medium flowing in the cooling medium path 20A located. Therefore, it is possible to suitably suppress the heat remaining in the region near the gate G of the injection mold 100. Such thermal residual suppression, is possible to prevent the heat transfer from the vicinity of the gate G of the injection mold 100 into the molten material resin R ₃ is located in the local part 31 of the mold cavity 30 located in the vicinity the gate G It becomes possible. Therefore, the molten raw material resin R ₃ located in the local portion 31 in the mold cavity 30 near the gate G becomes higher in temperature than the molten raw material resin R ₄ located in the other portion 32 in the mold cavity 30. Can be suppressed. As a result, in the cooling process of the molten raw material resin R in the mold cavity 30, the molten raw material resin located in a local part in the mold cavity 30 near the gate G is melted in other parts in the mold cavity 30. It becomes possible to suppress suitably that it becomes difficult to cool rather than raw material resin.

In one embodiment, if the hot feedstock resin flow path 10 (corresponding to the sprue) is connected directly to the gate G, a portion of the cross-sectional shape of the cooling medium passage 20A ₁ and the tip 50A of the hot mold sprue member 50 injection It is preferable to follow at least one of the cross-sectional shape of the contact portion 60 with the molding die 100 and the cross-sectional shape of the forming surface of the mold cavity 30 (FIG. 3).

When a part of the cross-sectional shape of the cooling medium passage 20A ₁ is along the cross-sectional shape of the contact portion 60 of the tip 50A and the injection mold 100 of the hot mold sprue member 50, the contact as compared with the case not along separation distance between the portion 60 and part of the coolant passage 20A ₁ becomes possible made relatively small. Thereby, the melting heat energy of the molten raw material resin flowing through the hot mold raw material resin flow path 10 that can be provided to the portion between the contact portion 60 and the mold cavity 30 via the contact portion 60 is converted into the contact portion 60. Can be effectively reduced by the cooling heat energy of the cooling medium flowing in the cooling medium passage 20A located in the portion between the mold cavity 30 and the mold cavity 30.

Incidentally, it is more preferred portion of the cross-sectional shape of the cooling medium passage 20A ₁ is substantially the same as the cross-sectional shape of the contact portion 60. When taking such embodiments, the separation distance at any point between the part of the contact portion 60 and the cooling medium passage 20A ₁ may be substantially uniform. Therefore, the cooling heat energy of the cooling medium in the cooling medium path 20 A ₁ can be uniformly supplied to any part of the contact part 60 due to the substantially uniform separation distance. Thereby, it is possible to more effectively reduce the melting thermal energy of the molten raw material resin in the hot type raw material resin flow path 10 provided from the contact portion 60.

Further, a part of the cross-sectional shape of the cooling medium passage 20A ₁ is along the cross-sectional shape of the forming surface of the mold cavity 30 located in the vicinity of the tip 50A of the hot mold sprue member 50, as compared with the case not along the separation between the portion of the forming surface and the cooling medium passage 20A ₁ of the mold cavity 30 can be relatively small. Thus, the heat of fusion energy of the molten material resin may be subjected to a portion between the localized portion 31 of the mold cavity 30 with the contact portion 60 and the mold cavity 30, the cooling medium flowing through the cooling medium passage 20A ₁ It can be effectively reduced by the cooling heat energy.

Incidentally, it is more preferred portion of the cross-sectional shape of the cooling medium passage 20A ₁ is substantially the same as the cross-sectional shape of the forming surface of the mold cavity 30. When taking such embodiments, the separation distance at any point between the part of the formation surface and the cooling medium passage 20A ₁ of the mold cavity 30 may be substantially uniform. Therefore, due to the substantially uniform distance the cooling heat energy of the cooling medium of the cooling medium passage 20A _1, the forming surface of the mold cavity 30 located in the vicinity of the tip 50A of the hot mold sprue member 50 either It becomes possible to provide uniformly with respect to a location. Thereby, it is possible to further effectively reduce the melting heat energy of the molten raw material resin that can be provided from the local portion 31 in the mold cavity 30 to the portion between the contact portion 60 and the mold cavity 30. Become.

In particular, the local area (i.e., the gate immediate vicinity region) cross-sectional shape and mold a portion of the cross-sectional shape of the cooling medium passage 20A ₁ to be subjected to the above contact portion 60 between the said contact portion 60 and the mold cavity 30 If along both the cross-sectional shape of the forming surface of the cavity 30, the cooling medium passage 20A ₁ may have a flattened cross-sectional shape (or an elliptical cross-sectional shape). When having such a shape, it is subjected to effective cooling medium passage 20A ₁ extensively in small local region (i.e., the gate immediate vicinity region) between the said contact portion 60 and the mold cavity 30 as compared to a true circle cross-sectional shape Is possible. Therefore, it is possible to effectively provide the cooling heat energy of the cooling medium in the cooling medium path 20 A _{1 to} the formation surface of the (1) contact portion 60 and (2) the mold cavity 30.

In one aspect, the cooling medium path 20A as the heat transfer control unit 20 preferably includes a support member 70 therein (see FIG. 4).

As described above, the cooling medium path 20A is a hollow flow path for flowing the cooling medium. Therefore, when the cross-sectional dimension and the longitudinal dimension of the hollow channel are relatively large, there is a possibility that the hollow channel cannot have sufficient strength against external pressure during molding. Therefore, from the viewpoint of sufficiently securing the strength against the external pressure, it is preferable to provide a support member 70 for supporting the inside of the cooling medium passage 20A. The support member 70 can serve as a “beam member” because it is provided from the viewpoint of sufficiently ensuring strength against external pressure. Although not particularly limited, the support member 70 may be made of the same material as the constituent material (for example, Fe) of the injection mold 100 (see the lower view of FIG. 4). FIG. 4 shows an aspect in which a plurality of support members 70 are provided in the cross section of the cooling medium path 20A. However, the present invention is not limited to this, and the plurality of support members 70 are preferably provided at predetermined intervals along the longitudinal direction of the cooling medium path 20A. As a result, the plurality of support members 70 are provided at predetermined intervals in both the longitudinal direction and the short direction of the cooling medium path 20A. Therefore, the cooling medium path 20A as a whole can further improve the strength against the external pressure.

In one aspect, the cooling medium path 20A as the heat transfer control unit 20 is also provided to other areas 100B other than the immediate area 100A of the gate G along the axial direction of the hot-type sprue member 50, and the cooling medium path 20A is entirely It preferably has a helical structure (see FIGS. 2 to 4).

The hot-type raw material resin flow path 10 can be provided with a plurality of heating sources 80 along the axial direction (sectional view) of the hot-type raw material resin flow path 10 from the viewpoint of continuously maintaining the molten state as a whole. In this case, not only the hot-type raw material resin flow channel 10 located in the vicinity of the gate G (that is, the downstream side of the hot-type raw material resin flow channel 10) but also the hot-type raw material resin flow channel 10 from the upstream side to the downstream side. The melting heat of the molten resin material in the hot mold material resin flow channel 10 can be transmitted to the injection mold 100 located around the mold material resin flow channel 10. Specifically, the heat of fusion of the molten resin material in the hot mold material resin flow path 10 may be transmitted from the region 100B other than the region 100A closest to the gate of the injection mold 100 to the region 100A closest to the gate. . Therefore, from the viewpoint of reducing the energy of the heat of fusion, it is preferable that the cooling medium path 20A is provided not only to the region 100A closest to the gate of the injection mold 100 but also to the other region 100B. In particular, the cooling medium path 20A preferably has a spiral structure as a whole. By adopting such a structure, the cooling medium path 20 A takes a form surrounding the hot-type raw material resin flow path 10 along the axial direction of the hot-type raw material resin flow path 10. Due to the surrounding form of the cooling medium path 20A, the portion extending from the upstream side to the downstream side of the hot mold material resin flow channel 10 is supplied to the injection mold 100 located around the hot mold material resin flow channel 10. The energy of the heat of fusion that can be achieved can be effectively reduced as a whole. In addition to this, due to the surrounding form of the cooling medium path 20A, a plurality of heating sources 80 provided along the axial direction (sectional view) of the hot mold material resin flow path 10 to the injection mold 100 are provided. It is possible to effectively reduce the heat energy of the heating source 80 transmitted as a whole.

In one embodiment, the separation distance between the cooling medium path 20A provided to the immediate area 100A of the gate G and the hot type sprue member 50 is such that the cooling medium path 20A provided to the other area 100B and the hot type sprue member 50 are separated. It is preferable that the distance between the two is smaller than the distance (see FIGS. 2 to 4).

As described above, according to the present invention, the heat transfer control unit 20 (for example, the cooling medium path) capable of performing heat transfer control at least in the immediate region 100A of the gate G as compared with other regions 100B other than the immediate region 100A of the gate G. 20A) ". According to such a technical idea, it is possible to the gate G side from the viewpoint of reducing the transmission of the melting heat of the raw material resin in the hot type raw material resin flow path 10 as much as possible to the mold cavity 30 side located in the vicinity of the gate G. It is preferable that the heat transfer control unit 20 (for example, the cooling medium path 20A) is as close as possible. On the other hand, the region 100B other than the immediate region 100A of the gate G is relatively far from the mold cavity 30 as compared to the immediate region 100A of the gate G. Therefore, it is considered that the other region 100B has less transferability of the melting heat of the raw material resin in the hot type raw material resin flow path 10 to the mold cavity 30 side than the immediate vicinity region 100A of the gate G. Considering these points, distance _{S 1} between the cooling medium passage 20A ₁ and the hot-type sprue member 50 to be subjected to the immediate vicinity region 100A of the gate G, the cooling medium passage 20A ₂ to be subjected to other regions 100B Is preferably smaller than the separation distance S ₂ between the hot-type sprue member 50 and the hot-type sprue member 50. Although not particularly limited, the separation distance S ₁ may be 1 mm to 10 mm, for example, 3 mm. On the other hand, the separation distance _{S 2} is 10 mm (10 mm excluding) ~ 50 mm, may be, for example, 25 mm.

As described above, since the immediate vicinity region 100A of the gate G located proximal to the mold cavity 30 is relatively high heat transfer rate to the mold cavity 30, the cooling medium passage 20A ₁ from the viewpoint of providing effective over a wide range, the cooling medium passage 20A ₁ may have a flattened cross-sectional shape (or an elliptical cross-sectional shape). On the other hand, since the heat transfer rate to the mold cavity 30 is relatively low in the other region 100B other than the immediate region of the gate G positioned on the distal side with respect to the mold cavity 30, the cooling medium path 20A _The meaning of providing ₂ in a wide range is not high. Therefore, the cooling medium passage 20A ₂ may have a true circular cross-section or a substantially perfect circle cross-sectional shape.

(Ii) Heat transfer control unit 20: In one aspect of the local low density portion in the injection mold 100 , the “heat transfer control unit 20” is an injection mold provided at least in the immediate area 100A of the gate G. 100 local low density portions 20B are preferable (see FIG. 5).

The specific mode of the heat transfer control unit 20 is not limited to the cooling medium path 20A. For example, the local low density part 20 B of the injection mold 100 can be used as the heat transfer control part 20. The “local low density portion 20 B” in the present specification refers to a component of the injection mold 100 having a relatively lower density than other portions in a broad sense. In the present specification, the “local low density portion 20B” is, in a narrow sense, a component of the injection molding die 100 when the injection molding die 100 is manufactured by the powder bed melt bonding method. The solidification density is relatively lower than that of the portion (for example, the solidification density is 40 to 95% (not including 95%)).

For example, when the hot-type raw material resin flow channel 10 (corresponding to the sprue) is directly connected to the gate G, the local low density portion 20B may be provided at least in the vicinity of the contact portion 60 located in the immediate region 100A of the gate G. . Although not shown, the local low density portion 20B may also be provided near the formation surface of the mold cavity 30 located in the immediate area 100A of the gate G. Without being limited to this, the local low density portion 20B may be provided in the vicinity of the interface region between the region 100B other than the immediate region 100A of the gate G and the hot-type raw material resin flow channel 10. From the viewpoint of simplifying the structure, it is preferable that the local low density portion 20B is provided along the region of the inner surface 100C of the injection mold 100 as shown in FIG.

In this case, the local low density portion 20B may have microscopic microscopic voids due to the relatively low density. Due to the presence of such fine voids in the local low density portion 20B, the hot-type raw material resin flow path from the hot-type raw material resin flow path 10 side to the region near the gate G of the injection mold 100 is compared with the case where no void exists. The local heat insulation of the heat of fusion of the raw material resin in 10 becomes possible. Further, due to the presence of such fine voids in the local low density portion 20B, the inside of the mold cavity 30 to the region 100A closest to the gate G of the injection mold 100 when filling / holding the molten raw material resin in the mold cavity is performed. It becomes possible to locally insulate the melting heat of the molten raw material resin located in the local portion 31 in the vicinity of the gate G.

As described above, due to the presence of the local low density portion 20B of the injection mold 100, the heat of the molten raw material resin R in the hot mold raw material resin channel 10 / the local portion 31 near the gate G in the mold cavity 30 It is possible to locally insulate the heat of the molten raw material resin R ₃ positioned to the region 100A immediately adjacent to the gate G of the injection mold 100. Such localized thermal insulation, suppress heat transfer to the molten material resin R ₃ is located in the local part 31 of the mold cavity 30 located from the gate G immediate vicinity region 100A adjacent the gate G of the injection mold 100 It becomes possible to do. Therefore, the molten raw material resin R ₃ located in the local portion 31 in the mold cavity 30 near the gate G becomes higher in temperature than the molten raw material resin R ₄ located in the other portion 32 in the mold cavity 30. Can be suppressed.

(Iii) Heat transfer control unit 20: In one aspect of the low heat transfer film provided on the surface of the injection mold 100 , the “heat transfer control unit 20” includes the low heat provided on the surface of the injection mold 100. It is preferable that the low heat transfer film 20C is provided at least in the immediate area 100A of the gate G (see FIG. 6).

The specific mode of the heat transfer control unit 20 is not limited to the cooling medium path 20A and the local low density unit 20B. For example, the low heat transfer film 20 C provided on the surface of the injection mold 100 can be used as the heat transfer control unit 20. As used herein, the “low heat transfer film 20C” refers to a film having a relatively low heat transfer property. The low heat transfer film 20C is not particularly limited, and examples thereof include a plating film and a ceramic film having a relatively low heat transfer property. Although not particularly limited, the film thickness may be 10 μm to 300 μm, for example, 150 μm.

For example, when the hot-type raw material resin flow path 10 (corresponding to the sprue) is directly connected to the gate G, the low heat transfer film 20C may be provided at least in the vicinity of the contact portion 60 located in the immediate area 100A of the gate G. Although not shown, the low heat transfer film 20C may also be provided near the formation surface of the mold cavity 30 located in the immediate area 100A of the gate G. Without being limited thereto, the low heat transfer film 20 C may also be provided in the vicinity of the interface region between the region 100 B other than the immediate region 100 A of the gate G and the hot-type raw material resin channel 10. From the viewpoint of simplifying the structure, it is preferable that a low heat transfer film 20C is provided along the region of the inner surface 100C of the injection mold 100 as shown in FIG. In addition to or instead of this, the low heat transfer film is applied not only to the inner surface 100C but also to the outer surface 50C of the hot-type sprue member 50 from the viewpoint of suppressing heat conduction from the inside of the hot-type sprue member 50 to the outside. May be further provided.

In this case, since the low heat transfer film 20C is a film having a relatively low heat transfer property, the low heat transfer film 20C is used for injection molding from the hot-type raw material resin flow path 10 side as compared with the case where the low heat transfer film 20C is not provided. It becomes possible to reduce the transferability of the melting heat of the raw material resin in the hot-type raw material resin flow path 10 toward the region near the gate G of the mold 100. Further, the low heat transfer film 20C is a film having a relatively low heat transfer property, and therefore, when the molten material resin is filled / held in the mold cavity, the gate G of the injection mold 100 is in the immediate vicinity. it is possible to reduce the transmission of heat of fusion of the molten material resin R ₃ is located in the local part 31 of the gate G near the mold cavity 30 to the area.

As described above, due to the existence of the low heat transfer film 20C, the melting heat of the molten raw material resin in the hot type raw material resin flow path 10 / the melting of the molten raw material resin R ₃ located in the local portion 31 near the gate G in the mold cavity 30 It is possible to reduce the heat transfer property of the heat injection mold 100 to the region 100A closest to the gate G. The reduction of such heat transfer, heat transfer to the molten material resin R ₃ is located in the local part 31 of the mold cavity 30 located from the gate G immediate vicinity region 100A adjacent the gate G of the injection mold 100 Can be suppressed. Therefore, the molten raw material resin R ₃ located in the local portion 31 in the mold cavity 30 near the gate G becomes higher in temperature than the molten raw material resin R ₄ located in the other portion 32 in the mold cavity 30. Can be suppressed.

Furthermore, the plating film, ceramic film, etc. that can be used as the low heat transfer film 20C are made of a material having high strength. Therefore, the plating film, ceramic film, etc. not only have the property of reducing the transferability of the melting heat of the raw material resin, but also have a pressure resistance characteristic and an abrasion resistance against external pressure generated during molding. It is advantageous.

In one aspect, the inner surface 100C of the injection mold 100 facing the outer surface 50C of the hot mold sprue member 50 is preferably located outside the outer surface 50C of the hot mold sprue member 50 (FIG. 2 to 6).

As described above, in the present invention, the heat transfer control unit 20 is provided at least in the immediate area 100A of the gate G. Thereby, it becomes possible to suppress that the heat of the molten resin material in the hot mold material resin flow path 10 can be transmitted to the injection mold 100 side. In order to suppress heat transfer of the molten resin raw material, it is preferable not only to provide the heat transfer control unit 20 but also to provide characteristics to the surface shape of the injection mold 100. Specifically, it is preferable that the inner surface 100 C of the injection mold 100 is positioned outside the outer surface 50 C of the hot mold sprue member 50. By adopting such a configuration, it is possible to provide a gap between the inner surface 100C of the injection mold 100 and the outer surface 50C of the hot mold sprue member 50. Due to the existence of such a gap, it is possible to prevent the heat of the molten resin material in the hot mold material resin flow path 10 from being transmitted to the injection mold 100 side. Note that at least the tip 50A of the hot mold sprue member 50 needs to be in contact with the injection mold 100 for installation in the injection mold 100, and therefore the contact portion (reference numeral 60 in FIGS. 2 to 6). Is equivalent to confirming that no gap is provided. Further, on the assumption that no gap is provided at the contact portion between the tip 50A of the hot mold sprue member 50 and the injection mold 100, in this embodiment, the hot mold sprue located on the upstream side of the hot mold sprue member 50 is used. It is preferable that no gap be provided between the outer surface 50C of the member 50 and the inner surface 100C of the injection mold 100 opposed thereto. Thus, when the hot mold sprue member 50 is viewed as a whole, the injection mold 100 whose outer surface 50C is opposed to the front end side (the most downstream side) of the hot mold sprue member 50 and the upstream side relatively. Will contact the inner surface 100C. Thereby, it is possible to further improve the placement stability of the hot mold sprue member 50 with respect to the injection mold 100.

(Manufacturing method of injection mold apparatus)
Hereinafter, the manufacturing method of the injection mold apparatus 200 (FIG. 1) according to an embodiment of the present invention will be described. An injection mold apparatus 200 according to an embodiment of the present invention is an injection mold 100 (comprising a core side and a cavity side), and for supplying a molten raw material resin into the injection mold 100. And a hot mold sprue member 50 having a hot mold material resin flow path 10 (corresponding to a sprue) inside. The injection mold 100 can be manufactured using the following “powder bed melt bonding method”. On the other hand, a commercially available product can be used for the hot-type sprue member 50.

The “powder bed fusion bonding method” used for manufacturing the injection mold 100 is a method capable of manufacturing a three-dimensional shaped object by irradiating a powder material with a light beam. In the method, a powder layer formation and a solidified layer formation are alternately and repeatedly performed based on the following steps (i) and (ii) to produce a three-dimensional shaped object.
(I) A step of irradiating a predetermined portion of the powder layer with a light beam and sintering or melting and solidifying the powder at the predetermined portion to form a solidified layer.
(Ii) A step of forming a new powder layer on the obtained solidified layer and similarly irradiating a light beam to form a further solidified layer.

According to such a manufacturing technique, it becomes possible to manufacture a complicated three-dimensional shaped object in a short time. When an inorganic metal powder is used as the powder material, the obtained three-dimensional shaped object can be used as the injection mold 100. The “metal powder” here may be, for example, an iron-based metal powder having an average particle diameter of about 5 μm to 100 μm.

An example is a powder bed fusion bonding method in which a metal powder is used as a powder material, and a three-dimensional shaped article manufactured thereby is used as an injection mold 100. As shown in FIG. 7, first, the squeezing blade 23 is moved to form a powder layer 22 having a predetermined thickness on the modeling plate 21 (see FIG. 7A). Next, a light beam L is applied to a predetermined portion of the powder layer 22 to form a solidified layer 24 from the powder layer 22 (see FIG. 7B). Subsequently, a new powder layer is formed on the obtained solidified layer and irradiated with a light beam again to form a new solidified layer. When the powder layer formation and the solidified layer formation are alternately performed in this manner, the solidified layer 24 is laminated (see FIG. 7C), and finally, a three-dimensional structure composed of the laminated solidified layer 24 is formed. A shaped object can be obtained.

By using the “powder bed fusion bonding method”, it is possible to provide a heat transfer control unit capable of performing heat transfer control at least in the immediate region of the portion serving as the gate compared to other regions other than the immediate region of the portion serving as the gate. It becomes possible. When the “powder bed fusion bonding method” is used, it is possible to provide the cooling medium path 20A and the local low density part 20B as the heat transfer control part 20 by locally reducing the irradiation energy density of the light beam. . When the low heat transfer film 20C is provided as the heat transfer control unit 20, a plating film used as the low heat transfer film 20C can be separately provided by vapor deposition sputtering. A ceramic film used as the low heat transfer film 20C can be separately provided by thermal spraying.

When the injection mold apparatus 200 obtained by the above method is used, the injection mold from the hot mold material resin flow path 10 side through the gate G due to the presence of the heat transfer control unit 20 in the closest region 100A of the gate. It becomes possible to suppress the heat transfer of the raw material resin in the hot type raw material resin flow path 10 toward the region 100A closest to the gate G of 100. Further, it is possible to prevent the heat of the molten raw material resin R located in the local portion 31 near the gate G in the mold cavity 30 from being transmitted to the region near the gate G of the injection mold 100. As described above, due to the presence of the heat transfer control unit 20, the melting heat of the molten raw material resin in the hot type raw material resin flow path 10 / the melting heat of the molten raw material resin located in the local portion 31 near the gate G in the mold cavity 30. Due to this, it is possible to suitably suppress heat remaining in the region 100A immediately adjacent to the gate G of the injection mold 100. Such thermal residual deterrent, arresting the heat transfer from the gate G immediate vicinity region of the injection mold 100 into the molten material resin R ₃ is located in the local part 31 of the mold cavity 30 located in the vicinity the gate G Is possible. Thereby, in the cooling process of the molten raw material resin R in the mold cavity 30, the molten raw material resin R ₃ located in the local portion 31 in the mold cavity 30 near the gate G becomes the other portion 32 in the mold cavity 30. It becomes possible to suppress suitably that it becomes difficult to cool rather than molten raw material resin R4 located in ( ₄₎ . Therefore, finally, it is possible to suitably obtain a highly accurate molded product as a whole.

As mentioned above, although the method for manufacturing a molded article using the injection mold apparatus and the injection mold apparatus according to an embodiment of the present invention has been described, the present invention is not limited to this. It will be understood that various modifications may be made by those skilled in the art without departing from the scope of the invention as defined in the claims.

The mold apparatus for injection molding according to one embodiment of the present invention can be used to obtain an injection molded product.

Cross-reference of related applications

The present application is Japanese Patent Application No. 2018-014898 (Filing Date: January 31, 2018, Title of Invention: “Injection Molding Device and Injection Molding Device Using the Molding Device) Claiming priority under the Paris Convention under "Method for"). All the contents disclosed in the application are incorporated herein by this reference.

DESCRIPTION OF SYMBOLS 200 Injection mold apparatus 100 Injection mold 100A Near area | region of a gate 100B Other area | regions other than the immediate area | region of a gate 100C Inner surface of the injection mold 70 Support member 60 The front end and injection molding of a hot mold sprue member 50 Hot mold sprue member 50A Tip of hot mold sprue member 50C Outer surface of hot mold sprue member 30 Mold cavity 20 Heat transfer controller 20A Cooling medium path 20A ₁ Cooling medium path 20A ₂ Cooling medium path separation distance S ₂ gates between 20B local low-density portion 20C low heat transfer film 10 hot feedstock resin passage G gates R molten starting resin S ₁ cooling medium path which is subjected to immediate area of the gate and the hot type sprue member The cooling medium path provided to other areas other than the immediate area and the hot type sprue member Distance of

Claims

An injection mold apparatus,
A hot mold material resin flow path connected to the mold cavity via the gate,
A mold apparatus for injection molding comprising a heat transfer control unit at least in a region near the gate.
A hot-type sprue member having the hot-type raw material resin flow path therein; and the hot-type sprue member includes an injection mold so that the hot-type raw material resin flow path is directly connected to the gate. Touching,
2. The injection mold apparatus according to claim 1, wherein the heat transfer control unit is positioned between a contact portion between a tip of the hot mold sprue member and the injection mold and the mold cavity. .
The mold apparatus for injection molding according to claim 1 or 2, wherein the heat transfer control unit is a cooling medium path provided at least in the immediate area of the gate.
The tip of the hot-type sprue member has a shape in which the diameter of the tip gradually decreases,
The cooling medium path as the heat transfer control unit is such that a part of the cross-sectional shape of the cooling medium path is a cross-sectional shape of the contact portion between the tip of the hot mold sprue member and the injection mold, and the mold The mold apparatus for injection molding according to claim 3, which is positioned between the contact portion and the mold cavity so as to be along at least one of the cross-sectional shape of the forming surface of the mold cavity.
The part of the cross-sectional shape of the cooling medium path as the heat transfer control unit is substantially the same as at least one of the cross-sectional shape of the contact portion and the cross-sectional shape of the mold cavity forming surface. The mold apparatus for injection molding as described in 2.
6. The mold apparatus for injection molding according to claim 3, wherein the cooling medium path as the heat transfer control unit has a flat cross-sectional shape.
The injection mold apparatus according to any one of claims 3 to 6, wherein the cooling medium path as the heat transfer control unit includes a support member therein.
The cooling medium path as the heat transfer control unit is also provided to other regions other than the immediate region of the gate along the axial direction of the hot-type sprue member,
The injection mold apparatus according to any one of claims 3 to 7, wherein the cooling medium passage has a spiral structure as a whole.
A separation distance between the cooling medium path provided to the immediate area of the gate and the hot-type sprue member is between the cooling medium path provided to the other area and the hot-type sprue member. The injection mold apparatus according to claim 8, wherein the mold apparatus is smaller than a separation distance.
The injection mold apparatus according to any one of claims 1 to 9, wherein the heat transfer control unit is a local low-density part of the injection mold provided at least in the immediate region of the gate.
Claims 3 to 10 dependent on claim 2, wherein an inner surface of the injection mold facing the outer surface of the hot mold sprue member is located outside the outer surface of the hot mold sprue member. The mold apparatus for injection molding as described in any of the above.
The heat transfer control unit includes a low heat transfer film provided on a surface of the injection mold, and the low heat transfer film is provided at least in the immediate region of the gate. The mold apparatus for injection molding in any one.
The injection according to any one of claims 3 to 12, subordinate to claim 2, comprising the injection mold and the hot mold sprue member, wherein the injection mold is provided by a powder bed melt bonding method. Mold equipment for molding.
A method for producing an injection-molded article using an injection mold apparatus,
The injection mold apparatus comprises a hot mold material resin flow path connected to a mold cavity through a gate, and has a heat transfer control unit at least in the immediate region of the gate,
Providing a molten raw material resin into the mold cavity through the hot-type raw material resin flow path;