Patent Description:
The present invention is related to an injection molding method, and, in particular, to an injection molding method using a molding device having a plurality of mold cavities with different pressure.

Foamed polymeric material has many advantages, such as high strength, low weight, impact resistance, thermal insulation, and others. Foamed polymeric articles can be made by injection molding or extrusion molding. For example, after the polymeric material is melted and mixed with a blowing agent to form a mixture, a force or pressure is applied to the mixture to inject or extrude the mixture into a mold cavity of a mold, and the mixture is foamed in the mold cavity to form the foamed polymeric article. There is a need to provide foamed polymeric articles with desirable properties.

D1 (<CIT>) discloses a foam molding system provided with a molding device, a material supplying machine, and a counter-pressure supplying device. The molding device is provided with: an inner mold made of gas permeable metal or gas permeable ceramics; and an outer mold made of gas impermeable metal and covering the inner mold. The inner mold and the outer mold are constituted with a fit-in structure or an integrated structure. The material supplying machine charges a resin containing a foam component into an inner mold cavity. The counter-pressure supplying device supplies the cavity with a fluid having a counter-pressure through the inner mold when charging the resin into the cavity.

D2 (<CIT>) provides an injection molding system including an extruding system. The extruding system includes a mixing unit configured to receive the polymeric material from the melting unit and configured to mix a polymeric material with a blowing agent and to form a mixture, wherein the mixing unit includes a mixing rotor disposed in a hollow mixing cartridge, and a ratio of a shortest distance between an inner sidewall of the hollow mixing cartridge and the mixing rotor to a diameter of the mixing rotor is in a range of <NUM>:<NUM> to <NUM>:<NUM>. The injection molding system further includes a discharging channel communicable with the extruding system, a molding device configured to receive the mixture from the discharging channel, and a supporting device configured to facilitate an engagement of the discharging channel and the molding device, the supporting device includes a first element protrudes from the extruding system and a second element disposed on the molding device. <CIT> discloses an injection molding method according to the preamble of claim <NUM>.

One purpose of the present invention is to provide a method of injection molding.

An injection molding system is disclosed. The injection molding system includes an extruding system, a first discharging channel, a molding device, and a pressure regulating system.

The extruding system is configured to produce a mixture of a polymeric material and a blowing agent. The first discharging channel communicable with the extruding system and including a first outlet configured to discharge the mixture from the extruding system. The molding device configured to receive the mixture from the first outlet. The pressure regulating system coupled to the molding device. The molding device includes a first mold cavity, a second mold cavity separated from the first mold cavity, a first feeding port communicable with the first mold cavity and engagable with the first outlet, a second feeding port communicable with the second mold cavity and engageable with the first outlet, and the pressure regulating system is configured to regulate pressures inside the first mold cavity and the second mold cavity.

The injection molding method is defined by the claims. The method includes providing a molding device, wherein the molding device includes a first mold cavity and a second mold cavity, a first feeding port in communication with the first mold cavity, and a second feeding port in communication with the second mold cavity; sensing a first pressure in the first mold cavity, and injecting a first gas into the first mold cavity until the first mold cavity is sensed to have a first predetermined pressure; and sensing a second pressure in the second mold cavity, and injecting a second gas into the second mold cavity until the second mold cavity is sensed to have a second predetermined pressure, wherein the first predetermined pressure is different from the second predetermined pressure.

Another injection molding method includes providing an extruding system configured to produce a mixture of a polymeric material and a blowing agent, a discharging channel communicable with the extruding system and including an outlet, wherein the outlet is engageable with the first feeding port and the second feeding port; providing a molding device, wherein the molding device includes a first mold cavity and a second mold cavity, a first feeding port in communication with the first mold cavity, and a second feeding port in communication with the second mold cavity; engaging the outlet with the first feeding port; injecting a first amount of the mixture into the first mold cavity through the outlet and the first feeding port; and disengaging the outlet from the first feeding port. The method further includes engaging the outlet with the second feeding port; injecting a second amount of the mixture into the second mold cavity through the outlet and the second feeding port; disengaging the outlet from the second feeding port; sensing a first pressure in the first mold cavity having the first amount of the mixture, and injecting a first gas into the first mold cavity or discharging a portion of gas from the first mold cavity until the first mold cavity is sensed to have a first predetermined pressure; and sensing a second pressure in the second mold cavity having the second amount of the mixture, and injecting a second gas into the second mold cavity or discharging a portion of gas from the second mold cavity until the second mold cavity is sensed to have a second predetermined pressure. The first predetermined pressure is different from the second predetermined pressure.

It should be noted that, in accordance with the standard practice in the industry, various features are not drawn to scale.

The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact.

Further, spatially relative terms, such as "beneath," "below," "lower," "above" "upper" and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures.

Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in the respective testing measurements. Also, as used herein, the term "about" generally means within <NUM>%, <NUM>%, <NUM>%, or <NUM>% of a given value or range. Alternatively, the term "about" means within an acceptable standard error of the mean when considered by one of ordinary skill in the art. Other than in the operating/working examples, or unless otherwise expressly specified, all of the numerical ranges, amounts, values and percentages such as those for quantities of materials, durations of times, temperatures, operating conditions, ratios of amounts, and the likes thereof disclosed herein should be understood as modified in all instances by the term "about. " Accordingly, unless indicated to the contrary, the numerical parameters set forth in the present disclosure and attached claims are approximations that can vary as desired. At the very least, each numerical parameter should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Ranges can be expressed herein as from one endpoint to another endpoint or between two endpoints. All ranges disclosed herein are inclusive of the endpoints, unless specified otherwise.

<FIG> is a schematic diagram view of an injection molding system <NUM> according to one embodiment of the present invention. The injection molding system <NUM> includes an extruding system <NUM>, a discharging channel <NUM>, a molding device 30a, and a pressure regulating system <NUM>. The extruding system <NUM> is configured to produce the mixture of a polymeric material and a blowing agent, and configured to inject the mixture into the discharging channel <NUM>. The extruding system <NUM> is connected to or communicable with the discharging channel <NUM>. The discharging channel <NUM> includes an outlet <NUM> configured to discharge the mixture from the extruding system <NUM>. The discharging channel <NUM> includes a first discharging channel 20a. In some embodiments, the first discharging channel 20a is communicable with the extruding system <NUM> and including a first outlet 21a disposed distal to the extruding system <NUM> and configured to discharge the mixture from the extruding system <NUM>. The molding device 30a is configured to receive the mixture from the first outlet <NUM> of the first discharging channel 20a. The pressure regulating system <NUM> is coupled to the molding device 30a.

In some embodiments, the polymeric material includes a high molecular weight polymer. In some embodiments, the polymeric material includes ethylene vinyl acetate (EVA), styrene-ethylene-butylene-styrene (SEBS), thermoplastic polyurethanes (TPU), thermoplastic polyester elastomer (TPEE) or the like. In some embodiments, the polymeric material includes a foamable material. In some embodiments, the blowing agent is a physical or chemical additive that releases gas, thereby forming pores in the thus-obtained foamed polymeric article. In some embodiments, the blowing agent is a physical additive. The physical blowing agent includes an atmospheric gas (e.g., nitrogen or carbon dioxide), a hydrocarbon, a chlorofluorocarbon, a noble gas, or a combination thereof. The blowing agent may be supplied in any flowable physical state, for example, a gas, a liquid, or a supercritical fluid (SCF).

<FIG> is a schematic diagram view of the extruding system according to aspects of the present disclosure in some embodiments. The extruding system <NUM> includes a melting unit <NUM>, a mixing unit <NUM>, a blowing agent supply unit <NUM>, an injection unit <NUM>, a first flow control element <NUM>, a second flow control element <NUM>, and a monitoring module <NUM>.

In some embodiments, referring to <FIG>, the melting unit <NUM> is configured to convey the polymeric material. In some embodiments, the melting unit <NUM> includes a pressing cartridge <NUM>, a first feeding passage <NUM>, a first discharging passage <NUM>, and a pushing member <NUM>. In some embodiments, the melting unit <NUM> further includes a feeding hopper <NUM>.

In some embodiments, the first feeding passage <NUM> and the first discharging passage <NUM> are respectively disposed at two ends of the pressing cartridge <NUM>. In some embodiments, the first feeding passage <NUM> communicates with an inner space <NUM> of the pressing cartridge <NUM>, and the first discharging passage <NUM> communicates with an external space of the pressing cartridge <NUM>, wherein the first feeding passage <NUM> is configured to deliver the polymeric material to the inner space <NUM> of the pressing cartridge <NUM>. In some embodiments, the feeding hopper <NUM> is configured to deliver a polymeric material to the inner space <NUM> of the pressing cartridge <NUM> through the first feeding passage <NUM>.

The pushing member <NUM> is configured to convey the polymeric material from the first feeding passage <NUM> to the first discharging passage <NUM>. In some embodiments, the pushing member <NUM> is disposed in the inner space <NUM> of the pressing cartridge <NUM>. In some embodiments, the pushing member <NUM> is disposed in the inner space <NUM> of the pressing cartridge <NUM> between the first feeding passage <NUM> and the first discharging passage <NUM>, and is used to force the polymeric material toward the first discharging passage <NUM>. In some embodiments, the pushing member <NUM> is rotatable relative to the pressing cartridge <NUM>. In some embodiments, the polymeric material is conveyed from the first feeding passage <NUM> to the first discharging passage <NUM> by rotation of the pushing member <NUM>. In some embodiments, the pushing member <NUM> is immovable in a direction parallel to the longitudinal axis of the pressing cartridge <NUM>.

In some embodiments, a length of the pushing member <NUM> extends along a length of the pressing cartridge <NUM>, and a ratio of a distance D1 between an inner sidewall <NUM> of the pressing cartridge <NUM> and the pushing member <NUM> and a diameter D2 of the pushing member <NUM> is in a range of about <NUM>:<NUM> to about <NUM>:<NUM>, and the polymeric material melted by the melting unit <NUM> may be uniformed. In some embodiments, a shortest distance D1 between an inner sidewall <NUM> of the pressing cartridge <NUM> and the pushing member <NUM> is substantially equal to or less than <NUM>. In some embodiments, the shortest distance D1 between the inner sidewall <NUM> of the pressing cartridge <NUM> and the pushing member <NUM> ranges between <NUM> and <NUM>.

The mixing unit <NUM> is configured to receive the polymeric material from the melting unit <NUM> and configured to mix the polymeric material with a blowing agent and to form a mixture of the polymeric material and the blowing agent. The mixing unit <NUM> includes a hollow mixing cartridge <NUM>, a second feeding passage <NUM>, a second discharging passage <NUM>, and a mixing rotor <NUM>.

The second feeding passage <NUM> and the second discharging passage <NUM> are respectively disposed at two ends of the mixing cartridge <NUM>. In some embodiments, the second feeding passage <NUM> is configured to deliver the polymeric material. In some embodiments, the second discharging passage <NUM> is configured to discharge the mixture.

The mixing rotor <NUM> is configured to mix the polymeric material with the blowing agent to form a mixture in the mixing cartridge <NUM>. In some embodiments, the mixing rotor <NUM> is disposed in the mixing cartridge <NUM>. In some embodiments, the mixing rotor <NUM> is disposed in the mixing cartridge <NUM> between the second feeding passage <NUM> and the second discharging passage <NUM>, so as to agitate the mixture in the mixing cartridge. The mixing rotor <NUM> is rotatable to mix the polymeric material with the blowing agent and to convey the mixture of the polymeric material and the blowing agent from the second feeding passage <NUM> to the second discharging passage <NUM>. In some embodiments, the mixing rotor <NUM> is immovable in a direction parallel to the longitudinal axis of the mixing cartridge <NUM>.

In some embodiments, a length of the mixing rotor <NUM> extends along a length of the hollow mixing cartridge <NUM>, and a ratio of a shortest distance D3 between an inner sidewall <NUM> of the hollow mixing cartridge <NUM> and the mixing rotor <NUM> and a diameter D4 of the mixing rotor <NUM> is in a range of about <NUM>:<NUM> to about <NUM>:<NUM>, and the mixture prepared by the extruding system <NUM> may be even and uniformed. In some embodiments, the mixture may be divided in to a plurality of portions, and a ratio of the blowing agent to the polymeric material of each portion of the mixture prepared by the extruding system <NUM> is substantially constant. In some embodiments, a ratio of the polymeric material to the blowing agent in a first portion of the mixture is substantially equal to a ratio of the polymeric material to the blowing agent in a second portion of the mixture. In some embodiments, the shortest distance D3 between the inner sidewall <NUM> of the hollow mixing cartridge <NUM> and the mixing rotor <NUM> is substantially equal to or less than <NUM>. In some embodiments, the shortest distance D3 between the inner sidewall <NUM> of the hollow mixing cartridge <NUM> and the mixing rotor <NUM> ranges between <NUM> and <NUM>.

<FIG> is an enlarge view of a portion of the extruding system according to aspects of the present disclosure in some embodiments. To enable the melted polymeric material and the blowing agent to mix uniformly in the mixing cartridge <NUM>, in some embodiments, referring to <FIG> and <FIG>, the mixing rotor <NUM> further includes a column-like body <NUM> in a cylindrical shape and rotatably disposed in the mixing cartridge <NUM>, and a groove portion <NUM> annularly arranged on the periphery of the column-like body <NUM>. Therefore, when the column-like body <NUM> rotates, the polymeric material and the blowing agent are agitated by the groove portion <NUM>, so as to achieve a desired mixing effect. In some embodiments, the shortest distance D3 is a shortest distance between the groove portion <NUM> and the inner sidewall <NUM> of the hollow mixing cartridge <NUM>.

In some embodiments, when the shortest distance D3 is a shortest distance between the groove portion <NUM> and the inner sidewall <NUM> of the hollow mixing cartridge <NUM>, the shortest distance D3 ranges between <NUM> and <NUM>. In some embodiments, the diameter D4 of the mixing rotor <NUM> ranges between the <NUM> to <NUM>.

In some embodiments, the melting unit <NUM> includes a hollow pressing cartridge <NUM> configured to accommodate the polymeric material and having a first pressure, and the mixing unit <NUM> includes a hollow mixing cartridge <NUM> having a second pressure. In some embodiments, in order to prevent backflow, the first pressure is greater than the second pressure. In some embodiments, the polymeric material is drawn from the melting unit <NUM> toward the mixing unit <NUM> by the difference between the first pressure and the second pressure.

The blowing agent supply unit <NUM> is connected to the mixing unit <NUM> and configured to convey the blowing agent into the mixing unit <NUM>. In some embodiments, the blowing agent supply unit <NUM> is positioned between the first flow control element <NUM> and the second flow control element <NUM>. In some embodiments, the blowing agent supply unit <NUM> is disposed proximal to the first flow control element <NUM> and distal to the second flow control element <NUM>.

In some embodiments, a blowing agent source (not shown) is connected to the blowing agent supply unit <NUM> and is configured to supply any type of blowing agent known to those of ordinary skill in the art. In some embodiments, the blowing agent is in the supercritical fluid state after being introduced into the mixing unit <NUM> by the blowing agent supply unit <NUM>.

In some embodiments, the first flow control element <NUM> is disposed at a first port <NUM> that connects the melting unit <NUM> to the mixing unit <NUM>. The first port <NUM> is configured to introduce the polymeric material from the melting unit <NUM> into the mixing unit <NUM>. The first port <NUM> is located between the melting unit <NUM> and the mixing unit <NUM>. In some embodiments, the first port <NUM> is configured to introduce the polymeric material from the pressing cartridge <NUM> of the melting unit <NUM> into the mixing cartridge <NUM> of the mixing unit <NUM>. In some embodiments, the polymeric material can be conveyed and/or drawn from the melting unit <NUM> to the mixing unit <NUM> through the first port <NUM> by a pressure difference between the first pressure and the second pressure.

In some embodiments, the first flow control element <NUM> is disposed between the melting unit <NUM> and the mixing unit <NUM> and is configured to control flow of the polymeric material from the melting unit <NUM> to the mixing unit <NUM>. The first flow control element <NUM> may be a valve, a movable cover or the like.

In some embodiments, the first flow control element <NUM> is configured to switch between an open configuration and a closed configuration. The open configuration of the first flow control element <NUM> allows the polymeric material to flow from the melting unit <NUM> into the mixing unit <NUM>, and the closed configuration of the first flow control element <NUM> prevents the polymeric material from flowing from the mixing unit <NUM> back to the melting unit <NUM>.

In some embodiments, the first flow control element <NUM> is configured to maintain a pressure difference between the melting unit <NUM> and the mixing unit <NUM>. In some embodiments, the first flow control element <NUM> is configured to maintain a pressure difference between the melting unit <NUM> and the mixing unit <NUM> by switching between the open configuration and the closed configuration, so that the polymeric material is not able to flow from the mixing cartridge <NUM> of the mixing unit <NUM> back to the pressing cartridge <NUM> of the melting unit <NUM>. In some embodiments, the first flow control element <NUM> is configured to adjust the first pressure and/or the second pressure in order to maintain the pressure difference between the first pressure and the second pressure. In some embodiments, the first flow control element <NUM> is in the closed configuration when the first pressure is similar to the second pressure.

In some embodiments, the injection unit <NUM> is configured to receive the mixture discharged from the second discharging passage <NUM> of the mixing unit <NUM> and to discharge the mixture out of the injection unit <NUM>. In some embodiments, the injection unit <NUM> is configured to inject the mixture, and at least one discharging channel <NUM> is communicable with the injection unit <NUM>.

In some embodiments, the injection unit <NUM> includes a hollow metering cartridge <NUM> configured to accommodate the mixture. The metering cartridge <NUM> has a hollow inner space <NUM>, wherein the inner space <NUM> is in communication with the second discharging passage <NUM> and configured to accommodate the mixture. The injection unit <NUM> further includes a connecting passage <NUM> in communication with the inner space <NUM> of the metering cartridge <NUM> and a discharging member <NUM> slidably disposed in the inner space <NUM> of the metering cartridge <NUM> and configured to discharge the mixture out of the metering cartridge <NUM> through an outlet <NUM>.

In some embodiments, referring back to <FIG>, the discharging channel <NUM> corresponds to one extruding system <NUM>. The mixture is flowed from one extruding system <NUM> or the outlet <NUM> into the discharging channel <NUM>.

<FIG> is a schematic diagram view of an injection molding system <NUM> according to one embodiment of the present invention. In some embodiments, referring to <FIG>, the injection molding system <NUM> includes a plurality discharging channels <NUM>. In some embodiments, the extruding system <NUM> corresponds to several discharging channels <NUM>. In some embodiments, the plurality of discharging channels <NUM> are connected to or communicable with the outlet <NUM> of the extruding system <NUM>. In some embodiments, each of the discharging channels <NUM> is attached to the outlet <NUM> of the injection unit <NUM>. The number of the discharging channels <NUM> may be adjusted according to the property of the mixture. The discharging channels <NUM> are extended parallel to each other and arranged adjacent to each other. In some embodiments, each discharging channel <NUM> may accommodate different amounts of the mixture injected from the outlet <NUM>. The discharging channels <NUM> may discharge the same or different amount of the mixture into the molding device 30a. In some embodiments, each discharging channel <NUM> may operate under different temperatures. In some embodiments, the discharging channels <NUM> includes the first discharging channel 20a and a second discharging channel 20b communicable with the extruding system <NUM>. The first discharging channel 20a and the second discharging channel 20b have widths same as or different from each other.

Each discharging channel <NUM> has an outlet <NUM> away from the injection unit <NUM>. In some embodiments, the outlets <NUM> can have different widths or diameters, and thus the outlets <NUM> can have different flow rates of the mixture. In some embodiments, the outlets <NUM> can inject different amounts of the mixture. In some embodiments, the second discharging channel 20b includes a second outlet 21b configured to discharge the mixture from the extruding system <NUM> into at least one of the first mold cavity 31a and the second mold cavity 31b. Each of the discharging channel <NUM> may be moved, extended, or retracted synchronously or separately. In some embodiments, the outlet <NUM> of the corresponding discharging channel <NUM> may be extended into and be retracted from the molding device 30a.

The molding device 30a of the injection molding system <NUM> shown in <FIG> and the injection molding system <NUM> shown in <FIG> are described below. The number of the molding devices 30a may be adjusted according to requirements. In some embodiments, one molding device 30a corresponds to one discharging channel <NUM> as shown in <FIG>. The mixture can be flowed from the extruding system <NUM> into one molding device 30a through one discharging channel <NUM>. In some embodiments, one molding device 30a corresponds to a plurality of discharging channels <NUM> as shown in <FIG>. The mixture can be flowed from the extruding system <NUM> into one molding device 30a through the plurality of the discharging channels <NUM>. <FIG> illustrates two discharging channels <NUM> corresponding to the molding device 30a for clarity and simplicity, but such example is intended to be illustrative only, and is not intended to be limiting to the embodiments. A person ordinarily skilled in the art would readily understand that any suitable number of the discharging channels <NUM> may be utilized.

In some embodiments, referring to <FIG> and <FIG>, the molding device 30a includes a mold cavity <NUM> configured to receive the mixture and a feeding port <NUM> engagable with the outlet <NUM> and communicable with the mold cavity <NUM>. The feeding port <NUM> is configure to dock the outlet <NUM>. According to the invention, the molding device 30a includes a first mold cavity 31a, a second mold cavity 31b separated from the first mold cavity 31a, a first feeding port 35a communicable with the first mold cavity 31a and engagable with the first outlet 21a, and a second feeding port 35b communicable with the second mold cavity 31b and engageable with the first outlet 21a. <FIG> and <FIG> illustrates only two mold cavities 31a, 31b for clarity and simplicity, but such example is intended to be illustrative only, and is not intended to be limiting to the embodiments. A person ordinarily skilled in the art would readily understand that any suitable number of the mold cavities 31a, 31b may be utilized, and all such combinations are fully intended to be included within the scope of the embodiments. Additionally, the mold cavities 31a, 31b are illustrated as having similar features, this is intended to be illustrative and is not intended to limit the embodiments, as the mold cavities 31a, 31b may have similar structures or different structures in order to meet the desired functional capabilities.

In some embodiments, the molding device 30a includes an upper mold base <NUM> and a mold under the upper mold base <NUM>. In some embodiments, the mold includes an upper mold <NUM> under the upper mold base <NUM>, a lower mold <NUM> opposite to the upper mold <NUM>, and a plurality of mold cavities <NUM> defined by the upper mold <NUM> and lower mold <NUM>. In some embodiments, the plurality of the mold cavities <NUM> includes the first mold cavity 31a and the second mold cavity 31b.

In some embodiments, the first mold cavity 31a and the second mold cavity 31b is defined by the upper mold <NUM> and the lower mold <NUM>. In some embodiments, the upper mold <NUM> and the lower mold <NUM> are complementary with and separable from each other. The lower mold <NUM> includes a plurality of lower mold cavities, and the upper mold <NUM> includes a plurality of upper mold cavities opposite to the lower mold cavities. In some embodiments, each of the mold cavity <NUM> is formed by one of the upper mold cavity and the corresponding lower mold cavity. Each of <FIG> and <FIG> illustrate one mold includes two mold cavities <NUM> for clarity and simplicity, but such example is intended to be illustrative only, and is not intended to be limiting to the embodiments.

In some embodiments, each of the mold cavities <NUM> is defined by an inner top wall <NUM>, an inner sidewall <NUM> and an inner bottom wall <NUM> opposite to the inner top wall <NUM>. The inner top wall <NUM>, the inner sidewall <NUM> and the inner bottom wall <NUM> defines the corresponding mold cavity <NUM>. In some embodiments, each of the feeding ports <NUM> are in communication with the corresponding inner top walls <NUM>.

In some embodiments, a first feeding port 35a is communicable with the first mold cavity 31a and engagable with the first outlet 21a. In some embodiments, at least one first feeding port 35a is communicable with the first mold cavity 31a. Each of the first feeding port 35a is communicable with the first mold cavity 31a and correspondingly engageable with the first outlet 21a. In some embodiments, the first feeding port 35a is disposed over the upper mold <NUM> or the lower mold <NUM> and is communicable with the first mold cavity 31a, the upper mold cavity or the lower mold cavity. <FIG> illustrates two first feeding ports 35a are included in one mold for clarity and simplicity, but such example is intended to be illustrative only, and is not intended to be limiting to the embodiments.

In some embodiments, at least one second feeding port 35b is communicable with the second mold cavity 31b. Each of the second feeding port 35b is communicable with the second mold cavity 31b and engageable with the first outlet 21a and/or the second outlet 21b. In some embodiments, the second feeding port 35b is disposed over the upper mold <NUM> or the lower mold <NUM> and is communicable with the second mold cavity 31b, the upper mold cavity or the lower mold cavity. <FIG> and <FIG> illustrate one second feeding port 35b in one mold for clarity and simplicity, but such example is intended to be illustrative only, and is not intended to be limiting to the embodiments. A person ordinarily skilled in the art would readily understand that one mold may include one or more second feeding ports 35b communicable with the second mold cavity 31b.

In some embodiments, the discharging channels <NUM> are received by the upper mold base <NUM>. In some embodiments, the first discharging channel 20a and the second discharging channel 20b are received by the upper mold base <NUM>. In some embodiments, the first discharging channel 20a and the second discharging channel 20b are at least partially surrounded by the upper mold base <NUM>. In some embodiments, the first feeding port 35a and the second feeding port 35b are configured to dock the first outlet 21a as shown in <FIG>. In some embodiments, the first feeding port 35a and the second feeding port 35b are configured to dock the first outlet 21a and the second outlet 21b respectively as shown in <FIG>. The mixture can be transported from the discharging channel <NUM> into the mold cavities <NUM> through the outlet <NUM> and the feeding port <NUM>. In some embodiments, the mixture can be transported from the first discharging channel 20a into the first mold cavity 31a and the second mold cavity 31b through the first outlet 21a and the first feeding port 35a as shown in <FIG>. In some embodiments, the mixture can be transported from the second discharging channel 20b into the second mold cavity 31b through the second outlet 21b and the second feeding port 35b as shown in <FIG>. In some embodiments, the first feeding ports 35a and the second feeding port 35b can have different widths or diameters. In some embodiments, the first feeding ports 35a can have different widths or diameters. In some embodiments, the mixture is injected into the first mold cavity 31a and the second mold cavity 31b and then foamed polymeric articles are formed in the first mold cavity 31a and the second mold cavity 31b after a period of time.

In some embodiments, referring to <FIG> and <FIG>, the upper mold base <NUM> includes openings <NUM> configured to receive the discharging channel <NUM>. Each of the openings <NUM> extends through the upper mold base <NUM>. The upper mold base <NUM> may be mounted on the upper mold <NUM> by a screw, a clamp, a fastening means or the like. In some embodiments, the material of the upper mold base <NUM> is same as the material of the upper mold <NUM>. In some embodiments, a width of the upper mold base <NUM> is greater than that of the upper mold <NUM> or the lower mold <NUM>. In some embodiments, the number of openings <NUM> corresponds to the number of the mold cavities <NUM>.

The pressure regulating system <NUM> coupled to the molding device 30a. The pressure regulating system <NUM> is configured to respectively regulate pressures inside the first mold cavity 31a and the second mold cavity 31b. In some embodiments, after the mixture is injected into the mold cavity <NUM>, the pressure in the mold cavity <NUM> is increased, and the pressure regulating system <NUM> may vent some gas to ensure that the mold cavity <NUM> is kept within a suitable pressure range. In some embodiments, the pressure regulating system <NUM> is configured to adjust or reduce the pressure in the mold cavity <NUM>.

In some embodiments, each of the mold cavities <NUM> is coupled to one or more pressure regulating systems <NUM>. In some embodiments, each of the mold cavities <NUM> may include different numbers of the pressure regulating systems <NUM> or no pressure regulating system <NUM>. In some embodiments, a first pressure regulating system 36a is coupled to the first mold cavity 31a and a second pressure regulating system 36b is coupled to the second mold cavity 31b. In some embodiments, the first mold cavity 31a and the second mold cavity 31b have different pressures.

In some embodiments, a junction point <NUM> is in connection with the corresponding mold cavity <NUM>. In some embodiments, the inner sidewall <NUM> or the inner bottom wall <NUM> of the mold cavity <NUM> includes the junction point <NUM>. In some embodiments, the junction point <NUM> is configured to allow a fluid or gas to enter into or exit from the corresponding mold cavity <NUM>.

Each of the pressure regulating system <NUM> may include a first gas conduit <NUM>, a second gas conduit <NUM>, a gas source <NUM>, a first valve <NUM>, a second valve <NUM>, and a pressure-sensing unit <NUM>. In some embodiments, one end of the first gas conduit <NUM> is coupled to the corresponding inner sidewall <NUM> or the inner bottom wall <NUM> of the mold cavity <NUM>. In some embodiments, one end of the first gas conduit <NUM> is coupled to the corresponding junction point <NUM>, and the other end of the first gas conduit <NUM> is coupled to the corresponding gas source <NUM>. In some embodiments, the gas source <NUM> is configured to supply a fluid or gas, in which a suitable fluid or gas may be supplied depending on the needs; for example, the fluid or gas may be air, inert gas, etc., but the present invention is not limited thereto.

The location, shape and number of the junction points <NUM> are not particularly limited, and may be adjusted depending on the needs. In some embodiments, each of the junction point <NUM> is a hole. In some embodiments, the junction point <NUM> is disposed at the corresponding inner sidewall <NUM> or the corresponding inner bottom wall <NUM> of the corresponding molding cavity <NUM> and penetrates the lower mold <NUM>. In some embodiments, each of the junction point <NUM> is configured to supply gas and discharge gas, wherein when the first valve <NUM> is open and the corresponding second valve <NUM> is closed, the fluid or gas is supplied to the corresponding mold cavity <NUM>; when the first valve <NUM> is closed and the corresponding second valve <NUM> is open, at least a portion of the fluid or gas in the corresponding mold cavity <NUM> is discharged.

In some embodiments, the first feeding ports 35a and second feeding port 35b are disposed at the inner top wall <NUM> or the inner sidewall <NUM> of the corresponding mold cavity <NUM>. In some embodiments, the first feeding port 35a and the corresponding junction point <NUM> are disposed oppositely with respect to the first mold cavity 31a; as an example but not limitation, the first feeding port 35a is disposed at the inner top wall <NUM>, and the junction point <NUM> is disposed at the inner bottom wall <NUM>. In some embodiments, the first feeding ports 35a are disposed at the inner top wall <NUM>, and the corresponding junction point <NUM> is disposed at the inner sidewall <NUM> of the first mold cavity 31a. In some embodiments, the first feeding port 35a is away from the corresponding junction point <NUM>.

The first valve <NUM> is disposed at the corresponding first gas conduit <NUM> and is configured to control whether the gas from the gas source <NUM> enters the corresponding mold cavity <NUM> through the corresponding first gas conduit <NUM> and the corresponding junction point <NUM>. The second gas conduit <NUM> coupled to the mold and in communication with the corresponding mold cavity <NUM>. In some embodiments, the second gas conduit <NUM> is coupled to the corresponding junction point <NUM>. The second valve <NUM> is disposed at the corresponding second gas conduit <NUM> and is configured to control whether the gas from the corresponding mold cavity <NUM> is discharged via the corresponding junction point <NUM> through the corresponding second gas conduit <NUM>.

In some embodiments, the second gas conduit <NUM> is coupled to the corresponding first gas conduit <NUM> and the corresponding junction point <NUM>. In some embodiments, one end of the second gas conduit <NUM> is in communication with a space with a pressure lower than the pressure in the corresponding mold cavity <NUM>; for example, an external environment or a negative pressure space; however, the present invention is not limited thereto. The location at which the second gas conduit <NUM> connects with the corresponding first gas conduit <NUM> is not particularly limited; for example, the two may be connected at one end adjacent to an end where the first gas conduit <NUM> connects to the corresponding junction point <NUM>. In some embodiments, the first valve <NUM> and the corresponding second valve <NUM> are not simultaneously open.

The pressure-sensing units <NUM> are configured to sense the pressure in the mold cavities <NUM>. The pressure-sensing units <NUM> sense the pressures inside the first mold cavity 31a and the second mold cavity 31b.

In some embodiments, the properties of foamed polymers are affected by the pore size and distribution across the polymer, whereas the pore size and distribution are related to the temperature, pressure, and feeding rate. The pressure-sensing unit <NUM> is not limited to any particular type, as long as it can sense the pressure and provide pressure information after sensing the pressure in the corresponding mold cavity <NUM>. The pressure regulating system <NUM> changes the condition at which the gas exits from/enters into the corresponding mold cavities <NUM> in accordance with the pressure information, so as to adjust the pressure in the corresponding mold cavity <NUM>, in such a manner that the foamed polymeric article thus obtained has the desired predetermined shape and property.

In some embodiments, the pressure-sensing unit <NUM> is disposed in the corresponding mold cavity <NUM>, the first gas conduit <NUM> or the second gas conduit <NUM>. In some embodiments, the pressure-sensing unit <NUM> is disposed in the corresponding mold cavity <NUM> and is away from the corresponding feeding port <NUM>. In some embodiments, each of the pressure regulating system <NUM> has a plurality of pressure-sensing units <NUM>. The number and location of the plurality of pressure-sensing units <NUM> are not particularly limited, for example, they can be arranged at the inner sidewalls <NUM> of the mold cavities <NUM> and spaced from each other, and/or anywhere in the first gas conduits <NUM>, and/or anywhere in the second gas conduits <NUM>; however, the present invention is not limited thereto.

In some embodiments, each of the injection molding system <NUM> shown in <FIG> and the injection molding system <NUM> shown in <FIG> further includes a control system <NUM>. The control system <NUM> is configured to control the extruding system <NUM>, the discharging channel <NUM>, and the molding devices 30a. In some embodiments, the control system <NUM> automatically controls the extruding system <NUM>, the discharging channel <NUM>, and the molding devices <NUM> in real time. In some embodiments, the control system <NUM> is communicable with the monitoring module <NUM> of the extruding system <NUM> in real time.

In some embodiments, the control system <NUM> includes a central processor <NUM> and a plurality of sensors <NUM> electrically connected to or communicable with the central processor <NUM>. In some embodiments, the sensors <NUM> are placed throughout the injection molding system <NUM>, <NUM> and configured to sense at least one processing condition (e.g., flow rate or viscosity of the mixture through the discharging channel <NUM>, an amount of the mixture discharged from the discharging channel <NUM>, a pressure inside the mold cavity <NUM>, etc.) at a predetermined position of the injection molding system <NUM> (e.g., the sequence of extruding to the first mold cavity 31a and the second mold cavity 31b, the alignment of the discharging channel <NUM> to the first mold cavity 31a and the second mold cavity 31b, the first outlet 21a, the second outlet 21b, the first feeding port 35a, and the second feeding port 35b, etc.). For example, at least one sensor <NUM> is installed at the outlet <NUM> for sensing the processing condition at the outlet <NUM>. In some embodiments, the sensor <NUM> is configured to detect the processing condition and transmit a signal or data based on the processing condition detected to the central processor <NUM> for further analysis.

In some embodiments, the control system <NUM> controls which of the first feeding port 35a and the second feeding port 35b the discharging channel <NUM> is docked to. In some embodiments, the cables <NUM> are electrically connected between the control system <NUM> and the extruding system <NUM>, the discharging channel <NUM>, and the molding device 30a. The cables <NUM> are configured to transmit the signal from the molding devices 30a to the extruding system <NUM> and the discharging channel <NUM>.

In some embodiments, the control system <NUM> is configured to process the pressure information detected by the pressure-sensing units <NUM>, and configured to adjust the mixing condition of the extruding system <NUM> and the extruding amount and timing of the discharging channel <NUM>. In some embodiments, the pressure-sensing units <NUM> provide the pressure informations to the control system <NUM>, and the control system <NUM> adjusts the first valve <NUM> and the second valve <NUM> in accordance with the pressure information. In some embodiments, the control system <NUM> adjusts the condition at which the gas enters into/exits from the mold cavities <NUM> in real time in accordance with the pressure information, and adjust the timing and amount of the mixture injected from the discharging channel <NUM> into the mold cavities <NUM>, so that during the injection molding process, the amount and rate of injection is within a suitable or predetermined range, and the pressures in the mold cavities <NUM> are within suitable or predetermined pressure ranges at all times. In some embodiments, the control system <NUM> further controls the feeding condition of the first feeding port 35a and the second feeding port 35b and the gas supply condition of the corresponding gas sources <NUM>. In some embodiments, the control system <NUM> and the first valves <NUM>, the second valves <NUM>, the pressure-sensing units <NUM> and the first feeding port 35a and the second feeding port 35b are electrically connected.

In some embodiments, the extruding system <NUM> and the discharging channel <NUM> are disposed over one of the plurality of mold cavities <NUM>. In some embodiments, referring to <FIG>, the first discharging channel 20a is horizontally and vertically movable relative to the first mold cavity 31a and the second mold cavity 31b. In some embodiments, the molding device 30a stationary. In some embodiments, the molding device 30a is movable relative to the extruding system <NUM> and the discharging channel <NUM>. In some embodiments, the extruding system <NUM> and the discharging channel <NUM> are stationary. In some embodiments, referring to <FIG>, the first discharging channel 20a is align with the first feeding port 35a, and the second discharging channel 20b is align with the second feeding port 35b. In some embodiments, the first discharging channel 20a and the second discharging channel 20b are vertically movable relative to the first mold cavity 31a and the second mold cavity 31b respectively.

In some embodiments, a molding device 30b shown in <FIG> is similar to the molding device 30a shown in <FIG> and <FIG>. In some embodiments, referring to <FIG>, the first gas conduit <NUM> is separated from the corresponding second gas conduit <NUM>, the second gas conduit <NUM> is coupled to the corresponding mold cavity <NUM>. In some embodiments, the junction point <NUM> of the molding device 30b is a hole, which includes a first opening <NUM> and a second opening <NUM>, wherein the first opening <NUM> is the connection with the first gas conduit <NUM>, and the second opening <NUM> is the connection with the second gas conduit <NUM>. In some embodiments, the first opening <NUM> is configured to intake gas, and the second opening <NUM> is configured to discharge gas. The locations of the first opening <NUM> and the second opening <NUM> are not particularly limited, as long as they are separated from each other. In some embodiments, the first opening <NUM> is away from the second opening <NUM>. In some embodiments, the first opening <NUM> and the second opening <NUM> are disposed oppositely with respect to the corresponding feeding port <NUM>. In some embodiments, the first opening <NUM> and the second opening <NUM> are disposed at the corresponding inner bottom wall <NUM> of the corresponding mold cavity <NUM>. In some embodiments, the first opening <NUM> and the second opening <NUM> are disposed at the inner sidewall <NUM> of the corresponding mold cavity <NUM>.

In some embodiments, a molding device 30c shown in <FIG> is similar to the molding device 30b shown in <FIG>. In some embodiments, referring to <FIG>, the first opening <NUM> of the molding device 30c has a plurality of first pores <NUM>, and the second opening <NUM> has a plurality of second pores <NUM>. In some embodiments, the plurality of first pores <NUM> are respectively connected with the first gas conduit <NUM>, whereas the plurality of second pores <NUM> are respectively connected with the second gas conduit <NUM>. In some embodiments, the number of second pores <NUM> is greater than the number of the first pores <NUM>. The locations of the plurality of first pores <NUM> and the plurality of second pores <NUM> are not particularly limited; they can be disposed alternately or at different regions in the mold cavity <NUM>, respectively. In some embodiments, an end at which the first gas conduit <NUM> connects with the corresponding mold cavity <NUM> have a plurality of first guiding channels <NUM>, wherein each first guiding channel <NUM> is connected to a corresponding first pore <NUM> and the first gas conduit <NUM>. In some embodiments, an end at which the second gas conduit <NUM> connects with the corresponding mold cavity <NUM> has a plurality of second guiding channels <NUM>, wherein each second guiding channel <NUM> is connected to a corresponding second pore <NUM> and the second gas conduit <NUM>.

In some embodiments, as shown in <FIG>, the first opening <NUM> of the molding device 30c is disposed at middle of the mold cavity <NUM>, and the second opening <NUM> is disposed at the periphery of the mold cavity <NUM>. In some embodiments, the plurality of second pores <NUM> surrounds the first opening <NUM>. In some embodiments, the first opening <NUM> and the plurality of second pores <NUM> are disposed at the inner bottom wall <NUM> of the mold cavity <NUM>. In some embodiments, the diameter of each second pore <NUM> is smaller of the diameter of the first opening <NUM>.

In some embodiments, referring to <FIG>, a molding device 30d includes a plurality of molds disposed under the upper mold base <NUM>. In some embodiments, the molding device 30d corresponds to two or more discharging channels <NUM>. <FIG> illustrates the molding device 30d including two molds for clarity and simplicity, but such example is intended to be illustrative only, and is not intended to be limited to the embodiments. A person ordinarily skilled in the art would readily understand that suitable number of the molds can be utilized, and all such combinations are fully intended to be included within the scope of the embodiments.

In some embodiment, each mold receives the mixture at the same or different time. Each mold of the molding device 30d includes one mold cavity <NUM> defined therein. In some embodiments, the first mold cavity 31a is defined in one mold, and the second mold cavity 31b is defined by another mold. In some embodiments, the pressure regulating system <NUM> is coupled to the plurality of the molds to control the pressures of the inside the first mold cavity 31a and the second mold cavity 31b.

In some embodiments, referring back to <FIG> and <FIG>, the injection molding system further include a supporting device <NUM> configured to facilitate an engagement of the discharging channel <NUM> and the molding device 30a. The supporting device <NUM> configured to facilitate the engagement of the discharging channel <NUM> to the molding devices 30a can be disposed at any suitable position on the injection molding system <NUM>, <NUM>. In some embodiments, the supporting device <NUM> is configured to support the discharging channel <NUM>. In some embodiments, the supporting device <NUM> is used to prevent separation of the discharging channel <NUM> and the first feeding port 35a or the second feeding port 35b during the injection of the mixture. In some embodiments, the control system <NUM> controls the supporting device <NUM> in real time. In some embodiments, the supporting device <NUM> may facilitate the engagement of the discharging channel <NUM> and the molding device 30b, 30c, 30d shown in <FIG>, <FIG> and <FIG>.

<FIG> is a schematic diagram of a portion of the injection molding system <NUM> according to one embodiment of the present disclosure. In some embodiments, referring to <FIG>, the supporting device <NUM> includes first and second elements <NUM>, <NUM> configured to engage with each other, wherein the first element <NUM> protrudes from the extruding system <NUM> or the discharging channel <NUM>, and the second element <NUM> is disposed on the molding devices 30a, but the disclosure is not limited thereto. In some embodiments, the first and second elements, <NUM>, <NUM> can be clamped to each other; for example, the second element <NUM> is configured to receive the first element <NUM>.

In some embodiments, the supporting device <NUM> is disposed above the mold cavity <NUM> of the molding device 30a. In some embodiments, the first element <NUM> is disposed on the discharging channel <NUM>, and the second element <NUM> is disposed on each molding devices 30a. In some embodiments, the second element <NUM> is disposed on the upper mold base <NUM> of the molding device 30a. In some embodiments, the first element <NUM> is a part of the extruding system <NUM> or the discharging channel <NUM>, while the second element <NUM> is a part of the molding device 30a. In some embodiments, the first element <NUM> is a part of the extruding system <NUM> and disposed adjacent to the discharging channel <NUM>, and the second element <NUM> is disposed above or facing toward the upper mold base <NUM> of the molding device 30a. In some embodiments, the first element <NUM> and the second element <NUM> can engage with each other, thereby tightly engaging the discharging channel <NUM> with the upper mold base <NUM> of the molding device 30a.

In some embodiments, the control system <NUM> further electrically controls the supporting device <NUM> of the molding devices 30a in real time. In some embodiments, the control system <NUM> controls the first element <NUM> to be connected to the molding device 30a, and controls the second element <NUM> to engage with the corresponding first element <NUM> for a predetermined temperature.

In some embodiments, in order to prevent separation of the extruding system <NUM> and the molding device 30a during the injection of the mixture, the engaged first element <NUM> is subjected to a force to against the second element <NUM>. The force may be equal to or greater than a threshold. The threshold may be adjusted according to the pressure in the mold cavity <NUM> and the diameter of the outlet <NUM>, or according to other factors.

The position and number of the first element <NUM> may be adjusted according to requirements, and are not particularly limited. The position and number of the second element <NUM> may also be adjusted according to requirements, and are not particularly limited. In some embodiments, the position and number of the second element <NUM> correspond to the position and number of the first element <NUM>. In an embodiment, the first element <NUM> can be disposed at any suitable position on the discharging channel <NUM>, and the second element <NUM> can be disposed at any suitable position on the molding device 30a. In some embodiments, the second element <NUM> is disposed above the upper mold <NUM>.

<FIG> is a schematic diagram of a portion of the injection molding system <NUM> according to one embodiment of the present invention. In some embodiments, referring to <FIG>, the supporting device <NUM> can be in either of two states, a locked state and an unlocked state. In the unlocked state, the first element <NUM> enters the corresponding second element <NUM> but has not yet been locked with the second element <NUM>. In other words, the first element <NUM> can still be withdrawn from the second element <NUM> when the supporting device <NUM> is in the unlocked state. In the locked state, the first element <NUM> enters and locks with the corresponding second element <NUM>, such that the first element <NUM> cannot be withdrawn from the second element <NUM>. <FIG> illustrates the supporting device <NUM> in the locked state. The supporting device <NUM> can be operated and controlled manually or automatically. The supporting device <NUM> can be switched between two states manually or automatically.

In some embodiments, the first element <NUM> is rotatably fixed to the extruding system <NUM>. In some embodiments, the first element <NUM> includes an elongated portion <NUM> and an arm portion <NUM>. The elongated portion <NUM> and the arm portion <NUM> are rotatable in a direction indicated by an arrow A. The elongated portion <NUM> is fixed to the extruding system <NUM> and extends in a first direction Z toward the upper mold <NUM>. The arm portion <NUM> is coupled to the elongated portion <NUM> and extends in a second direction X substantially orthogonal to the first direction Z or in a third direction Y substantially orthogonal to the first direction Z. In some embodiments, the first element <NUM> has an inverted T shape. After the first element <NUM> enters the second element <NUM>, the supporting device <NUM> is changed from the unlocked state to the locked state by rotation of the arm portion <NUM> of the first element <NUM>. In some embodiments, the first element <NUM> is locked with the second element <NUM> by rotating the arm portion <NUM> of the first element <NUM> with about <NUM> degrees. <FIG> illustrates the arm portion <NUM> is locked with the second element <NUM> after rotating the arm portion <NUM> with about <NUM> degrees. As a result, the supporting device <NUM> is in the locked state, and the discharging channel <NUM> is tightly engaged with the molding device 30a, and thus the injection of the mixture from the extruding system <NUM> and the discharging channel <NUM> to the molding device 30a can begin.

In some embodiments, the temperature of the discharging channel <NUM> is different from the temperature of the molding device 30a. The temperature of the discharging channel <NUM> is greater than that of the molding device 30a. In some embodiments, temperature of the discharging channel <NUM> ranges between <NUM> and <NUM>, and temperature of the molding device 30a may range between <NUM> and <NUM>.

In the present disclosure, a method of injection molding is disclosed. In some embodiments, an injection molding is performed by the method. The method includes a number of operations and the description and illustrations are not deemed as a limitation of the sequence of the operations. <FIG> and <FIG> collectively illustrate a flowchart of a method <NUM> of injection molding according to one embodiment of the present invention. The method <NUM> is not limited to the above-mentioned embodiments. In some embodiments, the injection molding method <NUM> uses the above-mentioned injection molding system <NUM> as shown in <FIG>.

In some embodiments, as shown in <FIG>, the injection molding method <NUM> includes step <NUM>, which includes providing an extruding system <NUM> configured to produce a mixture of a polymeric material and a blowing agent, a first discharging channel 20a communicable with the extruding system <NUM> and including an first outlet 21a, wherein the first outlet 21a is engageable with the first feeding port 35a and the second feeding port 35b. In some embodiments, the method <NUM> includes conveying the mixture from the extruding system <NUM> to the first discharging channel 20a. In some embodiments, the mixture is conveyed from the extruding system <NUM> to the first discharging channel 20a and accumulates in the first discharging channel 20a.

In some embodiments, the method <NUM> includes step <NUM>, which includes providing a molding device 30a, wherein the molding device 30a includes a first mold cavity 31a and a second mold cavity 31b, a first feeding port 35a in communication with the first mold cavity 31a, and a second feeding port 35b in communication with the second mold cavity 31b. In some embodiments, two or more first feeding ports 35a are in communication with the first mold cavity 31a. In some embodiments, the molding device 30a is disposed under the extruding system <NUM>, and the extruding system <NUM> is away from the molding device 30a.

In some embodiments, the method <NUM> includes step <NUM>, which includes sensing a first pressure in the first mold cavity 31a, and injecting a first gas G1 into the first mold cavity 31a until the first mold cavity 31a is sensed to have a first predetermined pressure. In some embodiments, a first pressure sensing unit 366a of a first pressure regulating system 36a senses the first pressure of the first mold cavity 31a. In some embodiments, the first gas G1 is injected into the first mold cavity 31a through the first pressure regulating system 36a in connection with the first mold cavity 31a. In some embodiments, the first gas G1 injected into the first mold cavity 31a through a first gas conduit <NUM> of the first pressure regulating system 36a. In some embodiments, the first gas G1 is any suitable gas depending on the need; for example, air; however, the present invention is not limited thereto.

In some embodiments, a first valve <NUM> of the first pressure regulating system 36a is opened so that the first gas G1 is injected into the first mold cavity 31a through the first gas conduit <NUM>. In some embodiments, the first gas G1 is injected into the first mold cavity 31a through the first pressure regulating system 36a when the first feeding port 35a is closed. In some embodiments, the first gas G1 is injected into the first mold cavity 31a through the first feeding port 35a.

In some embodiments, during the process of injecting the first gas G1 into the first mold cavity 31a, the pressure in the first mold cavity 31a is sensed continuously. In some embodiments, the first pressure sensing unit 366a continuously senses the first pressure in the first mold cavity 31a, and the first gas G1 is injected into the first mold cavity 31a until it is senses that the first mold cavity 31a has the first predetermined pressure; then, the first valve <NUM> and the second valve <NUM> of the first pressure regulating system 36a are closed, and the first gas G1 injection into the first mold cavity 31a is stopped. In some embodiments, the first predetermined pressure is greater than the atmospheric pressure. In some embodiments, the first predetermined pressure is less than the atmospheric pressure.

According to the invention, the method <NUM> includes step <NUM>, which includes sensing a second pressure in the second mold cavity 31b, and injecting a second gas G2 into the second mold cavity 31b until the second mold cavity 31b is sensed to have a second predetermined pressure. In some embodiments, the second gas G2 is injected into the second mold cavity 31b through a second pressure regulating system 36b in connection with the second mold cavity 31b. In some embodiments, the second gas G2 injected into the second mold cavity 31b through a first gas conduit <NUM> of the second pressure regulating system 36b. In some embodiments, the injection of the first gas G1 and the injection of the second gas G2 are performed simultaneously or separately.

In some embodiments, a first valve <NUM> of the second pressure regulating system 36b is opened so that the second gas G2 is injected into the second mold cavity 31b through the first gas conduit <NUM> of the second pressure regulating system 36b. In some embodiments, the second gas G2 is injected into the second mold cavity 31b through the second pressure regulating system 36b when the second feeding port 35b is closed. In some embodiments, the second gas G2 is injected into the second mold cavity 31b through the second feeding port 35b.

In some embodiments, during the process of injecting the second gas G2 into the second mold cavity 31b, the pressure in the second mold cavity 31b is sensed continuously. In some embodiments, the second pressure sensing unit 366b continuously senses the second pressure in the second mold cavity 31b, and the second gas G2 is injected into the second mold cavity 31b until it is senses that the second mold cavity 31b has the second predetermined pressure; then, the first valve <NUM> and the second valve <NUM> of the second pressure regulating system 36b, and the second gas G2 injection into the second mold cavity 31b is stopped. In some embodiments, the second predetermined pressure is greater than the atmospheric pressure. In some embodiments, the second predetermined pressure is less than the atmospheric pressure.

In some embodiments, the first predetermined pressure is different from the second predetermined pressure. In some embodiments, the first pressure and the second pressure are sensed in real time, and a control system <NUM> electrically connected to the molding device 30a controls the first pressure and the second pressure in real time.

In some embodiments, referring to <FIG>, the method <NUM> includes step <NUM>, which includes engaging the first outlet 21a with the first feeding port 35a. In some embodiments, after the engagement of the first outlet 21a and the first feeding port 35a, the pressure in the first mold cavity 31a of the molding device 30a is adjusted to the first predetermined pressure.

In some embodiments, before the engagement of the first outlet 21a with the first feeding port 35a of the first molding device 30a, the first discharging channel <NUM> is moved to a first position above the first molding device 30a. In some embodiments, the first discharging channel 20a is moved horizontally to the first position above the first molding device 30a. At the first position, the first discharging channels 20a is aligned with the corresponding openings <NUM> of the upper mold base <NUM> of the molding device 30a. In some embodiments, a distance between the first outlet <NUM> and the upper surface of the upper mold base <NUM> is greater than <NUM>.

In some embodiments, after the vertical alignment of the first discharging channel 20a with the corresponding openings <NUM>, the first discharging channel 20a is moved toward the first mold cavity 31a to be received by the corresponding openings <NUM> of the upper mold base <NUM>, and then the first outlet 21a is docked to the first feeding port 35a. In some embodiments, the first discharging channel 20a is moved vertically toward the first mold cavity 31a to be received by the corresponding openings <NUM> of the upper mold base <NUM>.

After the first outlet 21a is docked to the first feeding port 35a, the first outlet 21a and the first feeding port 35a form a flow path of the mixture, such that the first discharging channel 20a is communicable with the first mold cavity 31a through the first feeding port 35a. Is some embodiments, the flow path is formed by the two or more first feeding ports 35a and the first outlet 21a. The first outlet <NUM> must be tightly engaged with the first feeding port <NUM> in order to prevent the mixture from leaking out of the molding device 30a.

In some embodiments, the method <NUM> includes step <NUM>, which includes injecting a first amount M1 of the mixture into the first mold cavity 31a having the first predetermined pressure through the first outlet 21a and the first feeding port 35a. Referring to <FIG>, in some embodiments, after the first mold cavity 31a has the first predetermined pressure, the injection of the first amount M1 of the mixture begins. In some embodiments, the first mold cavity 31a has the first predetermined pressure before step <NUM>, and the first valve <NUM> and the second valve <NUM> of the first pressure regulating system 36a are closed. In some embodiments, in step <NUM>, the first amount of the mixture M1 is injected from the first discharging channel 20a into the first mold cavity 31a through the first outlet 21a and the first feeding port 35a. In some embodiments, the first discharging channel 20a is at least partially surrounded by the molding device 30a upon the injection of the first amount of the mixture M1.

In some embodiments, step <NUM> further includes securing the first discharging channel 20a to the molding device 30a to dock the first outlet 21a to the first feeding port 35a. In some embodiments, a force is provided by a supporting device <NUM> to prevent the separation of the extruding system <NUM> from the molding device 30a. In some embodiments, in step <NUM>, when the mixture is injected from the extruding system <NUM> into the molding device 30a, the molding device 30a may generate a reaction force opposite to an injection direction, and the reaction force may be transmitted to the first discharging channel 20a and the extruding system <NUM>, so that the first discharging channel 20a tend to separate from the molding device 30a. In some embodiments, the supporting device <NUM> provides support against the reaction force opposite to the injection direction.

In some embodiments, the first discharging channel 20a is secured to the molding device 30a by engaging a first element <NUM> of the supporting device <NUM> relative to a second element <NUM> of the supporting device <NUM> to secure the first discharging channel 20a with the molding device 30a, wherein the first element <NUM> protrudes from the extruding system <NUM>, and the second element <NUM> is disposed on the molding device 30a. In some embodiments, a force is provided by the supporting device <NUM> after the engagement to prevent the first discharging channel 20a separating from the molding device 30a.

In some embodiments, the first discharging channel 20a is secured to the molding device 30a by turning the supporting device <NUM> into the lock state, such as rotating the first element <NUM> of the supporting device <NUM> relative to and within the second element <NUM> of the supporting device <NUM> while engaging the first outlet 21a with the first feeding port 35a. In some embodiments, when the first outlet 21a is docked to the first feeding ports 35a, the first element <NUM> enters the second element <NUM> and then locked with the second element <NUM>. In some embodiments, the first discharging channel 20a is secured to the molding device 30a by rotating an elongated portion <NUM> and an arm portion <NUM> of the first element <NUM> of the supporting device <NUM>, the elongated portion <NUM> is fixed to the extruding system <NUM> and extends in a first direction Z toward the molding device 30a, and the arm portion <NUM> is coupled to the elongated portion <NUM> and extends in a second direction X different from the first direction Z.

In some embodiments, in step <NUM>, during the process of injecting the first amount of the mixture M1 into the first mold cavity 31a of the molding device 30a, the pressure in the first mold cavity 31a changes rapidly, and the first pressure-sensing unit 366a continuously senses the first pressure in the first mold cavity 31a. In some embodiments, the first amount of the mixture M1 is injected into the first mold cavity 31a of the molding device 30a from the first feeding port 35a, and the first predetermined pressure applies to the first amount of the mixture M1. In some embodiments, the first amount of the mixture M1 and the first gas G1 are disposed in the first mold cavity 31a, and the first amount of the mixture M1 will expand and foam in the first mold cavity 31a.

In some embodiments, the process of injecting the first amount of the mixture M1 into the first mold cavity 31a having the first predetermined pressure lasts for less than <NUM> second. In some embodiments, due to the first mold cavity 31a has the first predetermined pressure, the completion of the filling the first amount of the mixture M1 may be last for less than <NUM> second. During the injecting period or at the moment of the completion of the injection, the pressure in the first mold cavity 31a is sensed by the first pressure-sensing unit 366a in real time, and the pressure information is provided, so that the first pressure regulating system 36a can adjust the pressure in the first mold cavity 31a in accordance with the pressure information, and hence, the pressure in the first mold cavity 31a can be kept within the predetermined pressure range.

In some embodiments, when the first pressure of the first mold cavity 31a is sensed to be greater than the first predetermined pressure, the portion of the gas in the first mold cavity 31a is discharged from the first mold cavity 31a. In some embodiments, the first amount of the mixture M1 is injected into the first mold cavity 31a of the molding device 30a from the first feeding port 35a, and thereby increasing the first pressure to a third pressure in the first mold cavity 31a having the first amount of the mixture M1. In some embodiments, the third pressure in the first mold cavity 31a having the first amount of the mixture M1 is greater than the first predetermined pressure. In some embodiments, the pressure in the first mold cavity 31a of the molding device 30a is raised from the first predetermined pressure to the third pressure.

In some embodiments, still referring to <FIG>, the method <NUM> includes step <NUM>, which includes sensing the third pressure in the first mold cavity 31a having the first amount of the mixture M1, and injecting a third gas into the first mold cavity or discharging a portion of gas G3 from the first mold cavity 31a until the first mold cavity 31a is sensed to have a third predetermined pressure.

In some embodiments, after the first amount of the mixture M1 is injected into the first mold cavity 31a having the first predetermined pressure, the pressure in the first mold cavity 31a increases, and therefore, the setting of the third predetermined pressure ensures that the first mold cavity 31a is maintained within a suitable pressure range. In some embodiments, when the first mold cavity 31a reaches the third predetermined pressure, the injection of the third gas into the first mold cavity 31a or discharging a portion of gas G3 from the first mold cavity 31a is stopped.

In some embodiments, in step <NUM>, a portion of gas G3 is discharged from the first mold cavity 31a after injecting the third gas into the first mold cavity 31a. In some embodiments, step <NUM> further includes foaming the first amount of the mixture M1 in the first mold cavity 31a, according to the invention, and discharging the gas G3 in less than <NUM> second from the first mold cavity 31a through the first pressure regulating system 36a while the first amount of the mixture M1 is foaming in the first mold cavity 31a. Due to the discharging of the gas G3, the first amount of the mixture M1 in the first mold cavity 31a after the foaming process may have a lower density. In some embodiments, the gas G3 is discharged from the first mold cavity 31a through the junction point <NUM> of the first pressure regulating system 36a. According to the injection, the gas G3 is discharged from the first mold cavity 31a during or after the foaming process of the first amount of the mixture M1 in the first mold cavity 31a, until the third pressure in the first mold cavity 31a is decreased to the third predetermined pressure.

In some embodiments, when the first pressure-sensing unit 366a senses that the third pressure in the first mold cavity 31a is greater than the third predetermined pressure, the gas G3 in the first mold cavity 31a is discharged until the pressure in the first mold cavity 31a is within a predetermined pressure range. In some embodiments, the predetermined pressure range is between the first predetermined pressure and the third predetermined pressure. In some embodiments, the second valve <NUM> is open and the gas G3 in the first mold cavity 31a is discharged through the second gas conduit <NUM> of the first pressure regulating system 36a.

In some embodiments, referring to <FIG>, the method <NUM> includes step <NUM>, which includes disengaging the first outlet 21a from the first feeding port 35a of the molding device 30a. In some embodiments, after the injection of the first amount of the mixture M1 into the first mold cavity 31a, the first discharging channel 20a is disengaged from and moved away from the molding device 30a.

In some embodiments, before the disengaging of the first outlet 21a from the first feeding port 35a, the supporting device <NUM> is shifted into the unlocked state. In some embodiments, the supporting device <NUM> is changed from locked state to unlocked state by rotating a first element <NUM> of the supporting device <NUM> relative to and within a second element <NUM> of the supporting device <NUM> to unlock the discharging channel <NUM> from the molding device 30a. In some embodiments, during the disengagement of the first outlet 21a from the first feeding port 35a, the first element <NUM> is unlocked from the second element <NUM> and is then pulled away from the second element <NUM>.

In some embodiments, referring to <FIG>, the method <NUM> includes step <NUM>, which includes moving the first discharging channel 20a away from the first mold cavity 31a and toward the second mold cavity 31b. In some embodiments, the movement of the first discharging channel <NUM> includes moving the first discharging channel <NUM> from the first position above the first mold cavity 31a to a second position above the second mold cavity 31b. In some embodiments, the first discharging channel 20a are moved vertically away from the first mold cavity 31a, and then moved horizontally to the second position above the second mold cavity 31b.

In some embodiments, the setting and arrangement of the second mold cavity 31b is similar to the setting and arrangement of the first mold cavity 31a, and a detailed description thereof is omitted here for the sake of brevity.

In some embodiments, referring to <FIG>, the method <NUM> includes step <NUM>, which includes engaging the first outlet 21a with the second feeding port 35b. In some embodiments, the first discharging channel 20a is moved toward the second mold cavity 31b to be received by the corresponding openings <NUM> of the upper mold base <NUM>, and then the first outlet 21a is docked to the second feeding port 35b. In some embodiments, the method <NUM> further includes securing the first discharging channel 20a to the molding device 30a to dock the first outlet 21a to the second feeding port 35b. In some embodiments, the process of securing the first discharging channel 20a to the second feeding port 35b is similar to the process of securing the first discharging channel 20a to the first feeding port 35a in step <NUM>, and a detailed description thereof is omitted here for the sake of brevity.

According to the invention, referring to <FIG>, the method <NUM> includes step <NUM>, which includes injecting a second amount of the mixture M2 into the second mold cavity 31b having the second predetermined pressure through the first outlet 21a and the second feeding port 35b. In some embodiments, each of the first amount of the mixture M1 and the second amount of the mixture M2 has a predetermined ratio of the polymeric material to the blowing agent.

In some embodiments, after the second mold cavity 31b has the second predetermined pressure, the injection of the second amount of the mixture M2 begins. In some embodiments, the second mold cavity 31b has the second predetermined pressure before step <NUM>, and the first valve <NUM> and the second valve <NUM> of the second pressure regulating system 36b are closed. In some embodiments, in step <NUM>, the second amount of the mixture M2 is injected from the first discharging channel 20a into the second mold cavity 31b through the first outlet 21a and the second feeding port 35b. In some embodiments, the first discharging channel 20a is at least partially surrounded by the molding device 30a upon the injection of the second amount of the mixture M2. Injection of the second amount of the mixture M2 are respectively similar to step <NUM>, and similar details are not repeated herein.

In some embodiments, in step <NUM>, during the process of injecting the second amount of the mixture M2 into the second mold cavity 31b of the molding device 30a, the pressure in the second mold cavity 31b changes rapidly, and the second pressure-sensing unit 366b continuously senses the second pressure in the second mold cavity 31b. In some embodiments, the second amount of the mixture M2 is injected into the second mold cavity 31b of the molding device 30a from the second feeding port 35b, and the second predetermined pressure applies to the second amount of the mixture M2. In some embodiments, the second amount of the mixture M2 and the second gas G2 are disposed in the second mold cavity 31b, and the second amount of the mixture M2 will expand and foam in the second mold cavity 31b.

In some embodiments, the process of injecting the second amount of the mixture M2 into the second mold cavity <NUM> having the second predetermined pressure lasts for less than <NUM> second. During the injecting period or at the moment of the completion of the injection, the pressure in the second mold cavity 31b is sensed by the second pressure-sensing unit 366b in real time, and the pressure information is provided, so that the second pressure regulating system 36b can adjust the pressure in the second mold cavity 31b in accordance with the pressure information, and hence, the pressure in the second mold cavity 31b can be kept within the predetermined pressure range.

In some embodiments, the second amount of the mixture M2 is injected into the second mold cavity 31b of the molding device 30a from the second feeding port 35b, and thereby increasing the second pressure to a fourth pressure in the second mold cavity 31b having the second amount of the mixture M2. In some embodiments, the fourth pressure in the second mold cavity 31b having the second amount of the mixture M2 is greater than the second predetermined pressure. In some embodiments, the pressure in the second mold cavity 31b of the molding device 30a is raised from the second predetermined pressure to the fourth pressure. In some embodiments, the third pressure is different from the fourth pressure.

According to the invention, the method <NUM> includes step <NUM>, which includes sensing the fourth pressure in the second mold cavity 31b having the second amount of the mixture M2, and injecting a fourth gas into the second mold cavity 31b or discharging a portion of gas G4 from the second mold cavity 31b until the second mold cavity 31b is sensed to have a fourth predetermined pressure, wherein the third predetermined pressure is different from the fourth predetermined pressure.

In some embodiments, after the second amount of the mixture M2 is injected into the second mold cavity 31b having the second predetermined pressure, the pressure in the second mold cavity 31b increases, and therefore, the setting of the fourth predetermined pressure ensures that the second mold cavity 31b is maintained within a suitable pressure range. In some embodiments, when the second mold cavity 31b reaches the fourth predetermined pressure, the injection of the fourth gas into the second mold cavity 31b or discharging a portion of gas G4 from the second mold cavity 31b is stopped.

In some embodiments, in step <NUM>, the gas G4 is discharged from the second mold cavity 31b after injecting the fourth gas into the second mold cavity 31b. In some embodiments, step <NUM> further includes foaming the second amount of the mixture M2 in the second mold cavity 31b, according to the invention, and discharging the gas G4 in less than <NUM> second from the second mold cavity 31b through the second pressure regulating system 36b while the second amount of the mixture M2 is foaming in the second mold cavity 31b. Due to the discharging of the gas G4, the second amount of the mixture M2 in the second mold cavity 31b after the foaming process may have a lower density. In some embodiments, the gas G4 is discharged from the second mold cavity 31b through the junction point <NUM> of the second pressure regulating system 36b. According to the invention, the gas G4 is discharged from the second mold cavity 31b during or after the foaming process of the second amount of the mixture M2 in the second mold cavity 31b, until the fourth pressure in the second mold cavity 31b is decreased to the fourth predetermined pressure.

In some embodiments, when the second pressure-sensing unit 366b senses that the fourth pressure in the second mold cavity 31b is greater than the fourth predetermined pressure, the gas G4 in the second mold cavity 31b is discharged until the pressure in the second mold cavity 31b is within a predetermined pressure range. In some embodiments, the predetermined pressure range is between the second predetermined pressure and the fourth predetermined pressure. In some embodiments, the second valve <NUM> is open and a portion of the gas G4 in the second mold cavity 31b is discharged through the second gas conduit <NUM> of the second pressure regulating system 36b.

In some embodiments, referring to <FIG>, the method <NUM> includes step <NUM>, which includes disengaging the first outlet 21a from the second feeding port35b. In some embodiments, after the injection of the second amount of the mixture M2 into the second mold cavity 31b, the first discharging channel 20a is disengaged from and moved away from the molding device 30a. In some embodiments, before the disengaging of the first outlet 21a from the second feeding port 35b, the supporting device <NUM> is shifted into the unlocked state.

In the above-mentioned step <NUM> to step <NUM> and the following process, the control system <NUM> automatically controls the extruding system <NUM>, the first discharging channel 20a, the first and second mold cavities 31a, 31b, the supporting device <NUM> in real time. In some embodiments, the control system <NUM> controls movement of the extruding system <NUM> and the first discharging channel 20a. In some embodiments, the control system <NUM> controls movement of the molding devices 30a. In some embodiments, the control system <NUM> controls the injection of the first gas G1 into the first mold cavity 31a and the discharging of the portion of the first gas G1 from the first mold cavity 31a in accordance with the first pressure in the first mold cavity 31a, and control the injection of the second gas G2 into the second mold cavity 31b and the discharging of a portion of the second gas G2 from the second mold cavity 31b in accordance with the second pressure in the second mold cavity 31b.

In some embodiments, referring to <FIG>, the injection molding method <NUM> includes step <NUM>, which includes providing an extruding system <NUM> configured to produce a mixture of a polymeric material and a blowing agent, a first discharging channel 20a, and a second discharging channel 20b, wherein the first discharging channel 20a is communicable with the extruding system <NUM> and includes a first outlet 21a disposed distal from the extruding system <NUM>, the second discharging channel 20b is communicable with the extruding system <NUM> and includes a second outlet 21b disposed distal from the extruding system <NUM>, the first outlet 21a is engageable with the first feeding port 35a, and the second outlet 21b is engageable with the second feeding port 35b.

In some embodiments, the injection molding method <NUM> includes step <NUM>, which includes providing a molding device 30b, wherein the molding device 30b includes a first mold cavity 31a and a second mold cavity 31b, a first feeding port 35a in communication with the first mold cavity 31a, and a second feeding port 35b in communication with the second mold cavity 31b.

In some embodiments, the injection molding method <NUM> includes step <NUM>, which includes sensing a first pressure in the first mold cavity 31a, and injecting a first gas G1 into the first mold cavity 31a until the first mold cavity 31a is sensed to have a first predetermined pressure. In some embodiments, the process of performing step <NUM> is similar to the process of performing step <NUM>, and a detailed description thereof is omitted here for the sake of brevity.

According to the invention, the injection molding method <NUM> includes step <NUM>, which includes sensing a second pressure in the second mold cavity 31b, and injecting a second gas G2 into the second mold cavity 31b until the second mold cavity 31b is sensed to have a second predetermined pressure, wherein the first predetermined pressure is different from the second predetermined pressure. In some embodiments, the process of performing step <NUM> is similar to the process of performing step <NUM>, and a detailed description thereof is omitted here for the sake of brevity. In some embodiments, step <NUM> and step <NUM> are performed simultaneously or separately.

In some embodiments, referring to <FIG>, the injection molding method <NUM> includes step <NUM>, which includes engaging the first outlet 21a with the first feeding port 35a. In some embodiments, the process of performing step <NUM> is similar to the process of performing step <NUM>, and a detailed description thereof is omitted here for the sake of brevity.

In some embodiments, the injection molding method <NUM> includes step <NUM>, which includes engaging the second outlet 21b with the second feeding port 35b. In some embodiments, the process of performing step <NUM> is similar to the process of performing step <NUM>, and a detailed description thereof is omitted here for the sake of brevity. In some embodiments, the engagement of the first outlet 21a with the first feeding port 35a in step <NUM> and the engagement of the second outlet 21b with the second feeding port 35b in step <NUM> are performed simultaneously.

According to the invention, referring to <FIG>, the injection molding method <NUM> includes step <NUM>, which includes injecting a first amount of the mixture M1 into the first mold cavity 31a having the first predetermined pressure through the first outlet 21a and the first feeding port 35a. In some embodiments, the process of performing step <NUM> is similar to the process of performing step <NUM>, and a detailed description thereof is omitted here for the sake of brevity.

In some embodiments, the injection molding method <NUM> includes step <NUM>, which includes injecting a second amount of the mixture M2 into the second mold cavity 31b having the second predetermined pressure through the second outlet 21b and the second feeding port 35b. In some embodiments, the process of performing step <NUM> is similar to the process of performing step <NUM>, and a detailed description thereof is omitted here for the sake of brevity. In some embodiments, the injection the first amount of the mixture M1 and the injection the second amount of the mixture M2 are performed simultaneously or separately.

In some embodiments, the injection molding method <NUM> includes step <NUM>, which includes sensing a third pressure in the first mold cavity 31a having the first amount of the mixture M1, and injecting a third gas into the first mold cavity 31a or discharging a portion of gas G3 from the first mold cavity 31a until the first mold cavity 31a is sensed to have a third predetermined pressure. In some embodiments, the process of performing step <NUM> is similar to the process of performing step <NUM>, and a detailed description thereof is omitted here for the sake of brevity.

In some embodiments, the injection molding method <NUM> includes step <NUM>, which includes sensing a fourth pressure in the second mold cavity 31b having the second amount of the mixture M2, and injecting a fourth gas into the second mold cavity 31b or discharging a portion of gas G4 from the second mold cavity 31b until the second mold cavity 31b is sensed to have a fourth predetermined pressure. In some embodiments, the third predetermined pressure is different from the fourth predetermined pressure. In some embodiments, the process of performing step <NUM> is similar to the process of performing step <NUM>, and a detailed description thereof is omitted here for the sake of brevity. In some embodiments, step <NUM> and step <NUM> are performed simultaneously or separately.

In some embodiments, referring to <FIG>, the injection molding method <NUM> includes step <NUM>, which includes disengaging the first outlet 21a from the first feeding port 35a and the second outlet 21b from the second feeding port 35b. In some embodiments, disengaging the first outlet 21a from the first feeding port 35a and disengaging the second outlet 21b from the second feeding port 35b are performed simultaneously.

In the present disclosure, a method of injection molding defined by the claims is disclosed. The method includes a number of operations and the description and illustrations are not deemed as a limitation of the sequence of the operations. <FIG> is a flowchart illustrating a method <NUM> of injection molding according to one embodiment of the present invention. The method <NUM> is not limited to the above-mentioned embodiments. In some embodiments, the injection molding method <NUM> uses the above-mentioned injection molding system <NUM> as shown in <FIG> or the above-mentioned injection molding system <NUM> as shown in <FIG>. In some embodiments, as shown in <FIG>, the method <NUM> includes the following steps.

Step <NUM> includes providing a molding device, wherein the molding device includes a first mold cavity and a second mold cavity, a first feeding port in communication with the first mold cavity, and a second feeding port in communication with the second mold cavity.

Step <NUM> includes sensing a first pressure in the first mold cavity, and injecting a first gas into the first mold cavity until the first mold cavity is sensed to have a first predetermined pressure.

Step <NUM> includes sensing a second pressure in the second mold cavity, and injecting a second gas into the second mold cavity until the second mold cavity is sensed to have a second predetermined pressure, wherein the first predetermined pressure is different from the second predetermined pressure.

In the present disclosure, a method of injection molding is disclosed. The method includes a number of operations and the description and illustrations are not deemed as a limitation of the sequence of the operations. <FIG> and <FIG> collectively illustrate a flowchart of a method <NUM> of injection molding according to one embodiment of the present invention. The method <NUM> is not limited to the above-mentioned embodiments. In some embodiments, the injection molding method <NUM> uses the above-mentioned injection molding system <NUM> as shown in <FIG> or the above-mentioned injection molding system <NUM> as shown in <FIG>. In some embodiments, as shown in <FIG> and <FIG>, the method <NUM> includes the following steps.

Step <NUM> includes providing an extruding system configured to produce a mixture of a polymeric material and a blowing agent, a discharging channel communicable with the extruding system and including an outlet, wherein the outlet is engageable with the first feeding port and the second feeding port.

Step <NUM> includes engaging the outlet with the first feeding port.

Step <NUM> includes injecting a first amount of the mixture into the first mold cavity through the outlet and the first feeding port.

Step <NUM> includes disengaging the outlet from the first feeding port.

Step <NUM> includes engaging the outlet with the second feeding port.

Step <NUM> includes injecting a second amount of the mixture into the second mold cavity through the outlet and the second feeding port.

Step <NUM> includes disengaging the outlet from the second feeding port.

Step <NUM> includes sensing a first pressure in the first mold cavity having the first amount of the mixture, and injecting a first gas into the first mold cavity or discharging a portion of gas from the first mold cavity until the first mold cavity is sensed to have a first predetermined pressure.

Step <NUM> includes sensing a second pressure in the second mold cavity having the second amount of the mixture, and injecting a second gas into the second mold cavity or discharging a portion of gas from the second mold cavity until the second mold cavity is sensed to have a second predetermined pressure wherein the first predetermined pressure is different from the second predetermined pressure.

Claim 1:
An injection molding method (<NUM>), comprising:
providing a molding device (30a), wherein the molding device (30a) includes a first mold cavity (31a) and a second mold cavity (31b) separated from the first mold cavity, a first feeding port (35a) in communication with the first mold cavity (31a), and a second feeding port (35b) in communication with the second mold cavity (31b);
sensing a first pressure in the first mold cavity (31a), and injecting a first gas (G1) into the first mold cavity (31a) until the first mold cavity (31a) is sensed to have a first predetermined pressure;
sensing a second pressure in the second mold cavity (31b), and injecting a second gas (G2) into the second mold cavity (31b) until the second mold cavity (31b) is sensed to have a second predetermined pressure;
injecting a first amount of the mixture (M1) into the first mold cavity (31a) having the first predetermined pressure through the first feeding port (35a);
injecting a second amount of the mixture (M2) into the second mold cavity (31b) having the second predetermined pressure through the second feeding port (35b);
foaming the first amount of the mixture (M1) in the first mold cavity (31a);
foaming the second amount of the mixture (M2) in the second mold cavity (35b), and
characterized in that the method further comprises:
discharging at least a portion of the first gas (G1) from the first mold cavity (31a) during or after the foaming of the first amount of the mixture (M1) in the first mold cavity (31a) until the first mold cavity (31a) is sensed to have a third predetermined pressure; and
discharging at least a portion of the second gas (G2) from the second mold cavity (31b) during or after the foaming of the second amount of the mixture (M2) in the second mold cavity (31b) until the second mold cavity (31b) is sensed to have a fourth predetermined pressure,
wherein the first predetermined pressure is different from the second predetermined pressure, and the third predetermined pressure is different from the fourth predetermined pressure.