TWI623403B - Injection molding method and articles thereof - Google Patents

Abstract

The injection molding method of the present invention provides the flow channel system in an insert other than the mold. When the injection program is to be performed, the insert is incorporated into the mold to be clamped with the mold. So that the flow channel system communicates with the cavity inside the mold, and provides a communication passage between the cavity and the external injection machine, so that the polymer material emitted by the external injection device flows through the flow channel system. Entering the cavity, when the injection is completed, the mold is opened, and the insert is removed from the mold, and then the mold is closed to the mold clamping state for molding work, and at the same time, the insert is removed. Located in a temperature-controlled environment, the polymer raw material retained in the flow channel system maintains its fluidity, so that when the injection process of the next process is carried out, the flow path system is used to provide the polymer raw material. The flow channel.

Description

Injection molding method and articles thereof

The present invention relates to a polymer molding processing technique, and more particularly to an injection molding method and an article thereof.

The polymer processing technology for injection molding is to mold the polymer material by the injection machine to melt the polymer material into the closed cavity of the mold, so that the raw material can be polymerized in the closed cavity and molded by the cavity shape. Wherein, the flow channel system connecting the cavity between the cavity and the injection machine is usually disposed in the mold because it needs to communicate with the cavity, and therefore, the flow channel system accommodates the same amount of raw materials while providing the raw material flow space. It will be formed at the same time as the raw materials in the cavity and become waste.

By shortening the length of the runner system, it is a technique used by conventional techniques to reduce waste generation. However, the optimal runner system is not the equivalent of the shortest runner system, in order to reduce the generation of waste. It is necessary to make a compromise between the best flow path and the shortest flow path, and it is difficult to design the flow channel system. Moreover, no matter how fine it is, the waste formed in the flow channel system cannot be completely avoided; at the same time, in order to make the molding The waste material in the runner system is easily removed, and the position of the runner system is often fixed between the opposite mold faces of the docking template, so that the waste formed in the runner system is exposed while the mold is opened, Clearance; is a technology that is not known, and it is still not perfect, and it still needs to be improved.

Therefore, the main object of the present invention is to provide a method for injection molding of injection molding, the main technical feature of which is to provide a flow channel system for providing a polymer material flow passage, and to complete the flow of the polymer raw material into the mold cavity. After the injection process, it is separated from the mold and subjected to temperature control to avoid cooling and solidification of the polymer raw material remaining in the flow channel system.

Therefore, in order to achieve the above object, the injection molding method of the present invention provides the flow channel system in an insert other than the mold, and when the injection program is to be performed, the insert is incorporated into the mold. And clamping the mold, so that the flow channel system communicates with the cavity inside the mold, and provides a communication passage between the cavity and the external injection machine, so that the polymer emitted by the external injection machine The raw material flows through the flow channel system and enters the cavity. When the injection is completed, the mold is opened, and the insert is removed from the mold, and then the mold is closed to the mold clamping state for molding work. At the same time, the plug-in that is removed is placed in a temperature-controlled environment, so that the polymer material retained in the runner system maintains its flowability, so that when the injection process of the next program is carried out, The runner system provides a flow path for the polymer material.

In order to merge the mold with the mold and perform mold clamping, the insert includes a body, and a first abutting end surface disposed on the body is adjacent to the first die face of the mold. a second abutting end surface on the body is for abutting a second die face of the mold, and a runner system disposed in the body forms a sprue on one side of the body, and at the same time A gate is formed on the second abutting end surface to communicate with the cavity recessed on the second die surface.

The first abutting end surface and the second abutting end surface are complementary to each other in shape of the adjacent first die face and the second die face.

The first abutting end surface and the second abutting end surface are respectively located on opposite sides of the body.

(10) ‧‧‧ Injection molding method

(20)‧‧‧Mold

(21) ‧‧‧Upper film

(211)‧‧‧First face

(22) ‧‧‧ Lower die

(221)‧‧‧Second face

(23) ‧‧‧ cavity

(30)‧‧‧ Plugins

(31) ‧‧‧ Ontology

(32)‧‧‧First abutment end face

(33) ‧‧‧second abutment end face

(34) ‧‧‧ runner system

(341)‧‧‧Note

(342) ‧‧‧Gate

The first figure is a schematic representation of a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the invention will be described in conjunction with the drawings.

Referring to the first figure, in the preferred embodiment of the present invention, the injection molding method (10) for injection molding comprises the following steps:

a. Take a mold (20).

The mold (20) has a plate-shaped upper and lower die (21) (22) separated from each other, and the first die face (211) located at the bottom end face of the upper die (21) and the lower portion The die (22) is located in the shape of the second die face (221) of the upper end face, complementing each other, so that when the die (20) is closed, the first die face (211) and the second die are obtained. The mold faces (221) are butted against each other to clamp the mold (20), whereby the mold holes (23) are recessed on the second mold face (221) by the first die face (211). The hole is closed.

b. The mold (20) is opened.

The upper die face (21) and the lower die plate (22) are separated from each other to open the pocket of the cavity (23).

c. Take a plugin (30).

The insert (30) has a body (31), a first abutting end surface (32) and a second abutting end surface (33) are respectively disposed on opposite ends of the body (31), and a flow of holes a channel system (34) is disposed in the body (31), and forms a sprue (341) at one end of the body (31), and a gate (342) is formed on the second abutting end surface (33), wherein The sprue (341) is used to interface with the nozzle of the injection machine. The runner (342) is used to communicate with the cavity (23), so the number of each of them varies with the number of nozzles or the number of cavities, but the number of sprues and gates , position or shape, or the change, shape or extension of the pore size of the runner system itself, etc., are all well-known techniques in the design of polymer molding molds, and are not the technical targets of the proposed improvement of the present invention. That is to say, it is no longer a question.

d. Insert the insert (30) into the mold (20).

The insert (30) is interposed between the upper die (21) and the lower die (22) in a mold opening state, wherein the first abutting end face (32) faces the first die face (211) And having a shape complementary thereto, and the second abutting end face (33) faces the second die face (221) and has a shape complementary thereto.

e. First clamping and injection.

The mold (20) is clamped to form a mold clamping state in which the insert (30) is sequentially overlapped between the upper mold piece (21) and the lower mold piece (22), thereby making the flow path The system (34) communicates with the cavity (23) via the gate (342); and subsequently, a polymer material such as an ethylene vinyl acetate copolymer is injected by an injection machine, and flows through the flow path system (34). The cavity (23).

f. Open the mold.

After the quantitative polymer material is injected into the cavity (23), the mold (20) is opened, and the insert (30) and the upper die (21) and the lower die (22) are separated from each other.

g. Remove the plug-in (30) and perform temperature control.

After the mold (20) is opened, the insert (30) between the upper die (21) and the lower die (22) is removed, and the runner system (34) is placed in a possession In the temperature-controlled environment, the flowable state of the polymer raw material retained in the flow channel system (34) is maintained, and the temperature-free cooling is prevented to be solid. Chemical.

Wherein, in order to maintain the temperature of the environment in which the runner system (34) is located, in addition to supplying heat energy, such as: providing a flow path of the hot fluid inside the body (31), or attaching a heating plate thereto On the main body (31), even in the form of radiation to the thermal energy, it is also necessary to avoid the thermal insulation technology of the flow channel system (34) and the thermal energy of the polymer material retained therein. Therefore, the specific technical contents of the temperature control are exemplified.

h. second clamping and forming

After the insert (30) is removed, the upper mold piece (21) and the lower mold piece (22) are butt-joined to each other, thereby closing the mold cavity (23) and injecting the mold cavity (23). The internal polymer material is molded.

Thereby, through the temperature control provided by the flow channel system (34), the polymer raw material retained in the flow channel system (34) is maintained in a flowable state without cooling and solidifying, thereby blocking the flow passage. Thereby, the flow channel system (34) can continue to provide the flow channel directly during the next injection process without affecting the progress of the injection process, and at the same time, for the molded product, The flow channel system (34) is separated from the mold (20) when the step h is performed. Therefore, when the molding is performed, there is no state in which the cavity and the flow path remain in communication as in the prior art. The production of waste.

Claims (9)

An injection molding method for injection molding is to place a first-class system in an insert and insert the insert into a mold, so that the mold is first clamped, thereby making the runner system and the mold The mold holes are connected, and then the polymer material injected by an injection machine flows into the mold cavity of the mold through the flow channel system. After the injection is completed, the mold is opened and the insert is removed from the mold, and the mold is maintained. The temperature of the environment in which the runner system is located prevents the polymer material located in the runner system from cooling and solidifying. According to the injection molding method of the injection molding described in claim 1, wherein, after the insert is removed from the mold, the mold is subjected to a second mold clamping, so that the polymer raw material is molded in the filled cavity. Finished. The injection molding method according to the first or second aspect of the invention, wherein the polymer raw material comprises an ethylene vinyl acetate copolymer. An injection molding method for injection molding, comprising the steps of: a. taking a mold formed by at least two die sheets adjacent to each other; b. taking a plug-in having a runner system; c. inserting the plug-in Between the two molds of the mold, the flow channel system located in the insert communicates with the mold cavity inside the mold; d. the polymer material is injected by an injection machine and injected into the mold cavity inside the mold through the flow channel system. Opening the mold, removing the insert, maintaining the temperature of the environment in which the runner system is located, and preventing the polymer material located in the runner system from cooling and solidifying; f. clamping the mold to fill the mold The polymer material of the mold cavity inside the mold is molded type. According to the injection molding method of the injection molding described in claim 4, in the step e, the temperature of the environment in which the runner system is located is equal to or higher than the melting point of the polymer raw material. An insert for inserting into a mold, comprising: a body; a first abutting end surface on the body for abutting a first die face of the mold; a second abutting end face located at the a body adjacent to a second die face of the mold; a first-class track system disposed in the body, forming a sprue on one side of the body, and forming a gate on the second abutting end face, It is in communication with a cavity recessed on the second die face. The insert of the sixth aspect of the invention, wherein the first abutting end surface and the second abutting end surface are respectively located at opposite side ends of the body. The insert of claim 6, wherein the first abutting end surface and the first die face are complementary to each other. The insert of the sixth aspect of the invention, wherein the second abutting end surface and the second die face are complementary to each other.