Injection molding

Abstract

In a first aspect, an injection molding system for injecting an injection molded component is provided. The system comprises a plastic material feeding mechanism to feed a mold assembly, wherein the mold assembly comprises a component mold cavity and a feeding portion; the plastic material feeding mechanism being configured to supply plastic material to the feeding portion and force plastic material to flow through the component mold cavity. In a further aspect, a method for forming an injection molded component from a plastic material is also provided. The method comprises providing the injection molding system, supplying a first amount of plastic material to the feeding portion, and supplying a second amount of plastic material to the feeding portion.

Description

[0001] Injection molding

[0002] The present application claims the benefit and priority of EP24382885.2, filed on August 6, 2024.

[0003] The present disclosure relates to injection molding systems for injecting an injection molded component, and methods for forming the injection molded component from a plastic material.

[0004] BACKGROUND

[0005] Injection molding is a technique used to produce injection molded components, for example, components made from plastic material. Injection molding may be implemented using injection molding machines that feed mold assemblies.

[0006] The injection molding machines usually comprise a barrel. The injection molding machine can also include a hopper located at one end of the barrel, and a nozzle located at the opposite end of the barrel. The raw plastic material can be fed into the barrel through the hopper.

[0007] The injection molding machines may have a heater associated with the barrel. The raw material inside the barrel may be melted by the heat provided by the heater. The injection molding machine usually includes a ram or a rotating screw inside the barrel. The ram or rotating screw is configured to push the fluid material through the nozzle.

[0008] The mold assembly may have a runner that receives the fluid material from the nozzle. The runner may end at a gate that provides the mold cavity with fluid material.

[0009] Several gates may be required to provide the mold cavity with plastic material. Configurations having several gates may cause a plurality of material flows inside the mold cavity during injection process. Each material flow has a front flow. A pair of front flows may cause a weld or flow line at the meeting point of the two front flows. The weld and / or flow lines may affect the quality and / or aesthetics of the finished component. A weld line may involve a potential weak point.

[0010] The present disclosure provides examples of systems and methods that at least partially resolve some of the aforementioned disadvantages. SUMMARY

[0011] In a first aspect, an injection molding system for injecting an injection molded component is disclosed. The system comprises a plastic material feeding mechanism, and a mold assembly. The mold assembly comprises a component mold cavity and a feeding portion. The component mold cavity comprises a component mold cavity crosssection extending between an inlet portion and end portion. The component mold cavity cross-section spans a component mold cavity length defining an inlet portion length and an end portion length. The feeding portion comprises a feeding chamber for feeding the component mold cavity with plastic material, wherein the feeding chamber comprises a feeding outlet in fluid communication with the inlet portion of the component mold cavity, wherein the feeding outlet spans a feeding outlet length; wherein the inlet portion length corresponds to the feeding outlet length. The feeding portion further comprises a channel system for receiving plastic material from the plastic material feeding mechanism and distributing the plastic material in the feeding chamber. The plastic material feeding mechanism is configured to supply a first amount of plastic material to the channel system at a first value of a material parameter and supply a second amount of plastic material to the channel system at a second value of the material parameter when a predetermined portion of the first amount of plastic material is built-up in the feeding chamber to force the predetermined portion of the first amount of plastic to flow towards the end portion of the component mold cavity.

[0012] According to this aspect, the predetermined portion of the first amount of plastic material is accumulated or stored inside the feeding chamber. A homogenous and smooth mass of plastic material may be formed in the feeding chamber. A homogenous and smooth mass of plastic material may mean that flow fronts may be avoided or at least reduced in the plastic material accumulated within the feeding chamber. A single front flow may be formed inside the feeding chamber. This may be achieved regardless of the number of gates.

[0013] When the plastic material feeding mechanism is actuated, the second amount of plastic material may push the predetermined portion of the first amount of plastic. The second amount of plastic material may push the single front flow of the feeding chamber. The single front flow may enter the inlet portion of the component mold cavity towards the end portion of the component mold cavity. As the flow fronts may be significantly reduced or avoided, the finished component may be void of weld and / or flow lines. This may improve the mechanical features of the obtained component and / or aesthetics.

[0014] In a further aspect, a method for forming an injection molded component from a plastic material is disclosed. The method comprises providing an injection molding system according to any of the examples disclosed herein, supplying a first amount of plastic material to the channel system at a first value of a material parameter, and supplying a second amount of plastic material to the channel system at a second value of the material parameter when a predetermined portion of the first amount of plastic material is built-up in the feeding chamber to force the predetermined portion of the first amount of plastic to flow towards the end portion of the component mold cavity.

[0015] Advantages derived from this aspect may be similar to those mentioned regarding the first aspect.

[0016] The material parameter may comprise at least one of pressure, temperature, and / or speed.

[0017] Throughout the present disclosure, the first value of the material parameter and the second value of the material parameter may comprise the pressure values related to flow rates of plastic material pouring into the mold assembly from the plastic material feeding mechanism.

[0018] DESCRIPTION OF THE DRAWINGS

[0019] Non-limiting examples of the present disclosure will be described in the following, with reference to the appended drawings, in which:

[0020] Figure 1 schematically illustrates a plastic material feeding mechanism and a clamping unit;

[0021] Figure 2 schematically illustrates a cross-section view of an injection molding system according to one example;

[0022] Figure 3 schematically illustrates a perspective and partial view of the mold assembly of the injection molding system of Figure 2; Figure 4A schematically illustrates a longitudinal-section view of a mold assembly in which a predetermined portion of a first amount of plastic material is built-up in a feeding chamber according to one example;

[0023] Figure 4B schematically illustrates a longitudinal-section view of the mold assembly of Figure 4A in which the predetermined portion of plastic material is pushed from the feeding chamber to the component mold cavity according to one example;

[0024] Figure 5 schematically illustrates a channel system according to one example;

[0025] Figure 6 schematically illustrates a partial view of the feeding portion according to one example;

[0026] Figure 7 schematically illustrates a component mold cavity according to one example;

[0027] Figure 8 schematically illustrates a view of a control unit of a system according to one example of the present disclosure; and

[0028] Figure 9 is a block diagram of a method for forming an injection molded component from a plastic material according to an example of the present disclosure.

[0029] DETAILED DESCRIPTION OF EXAMPLES

[0030] In these figures, the same reference signs have been used to designate matching elements.

[0031] Figure 1 schematically illustrates an example of a plastic material feeding mechanism 110 and a clamping unit 170. The plastic material feeding mechanism 110 of Figure 1 comprises a hopper 112 connected to a barrel 115. The hopper 112 may receive the plastic material 111 in a raw condition, for instance pellets, granules or the like. The hopper 112 may receive recycled and / or virgin plastic material.

[0032] The barrel 115 has an extruder 113 configured to drive the plastic material 111 fed by the hopper 112. In the example of Figure 1, the extruder 113 comprises a rotating screw. The barrel 115 is associated with a heater 116 to melt the plastic material 111. At one end of the barrel 115 there is arranged a nozzle 114 configured to control the passage of plastic material from the extruder 113 into the mold assembly 150. The operation of the rotating screw may cause the plastic material to move towards the nozzle 114. The plastic material provided by the nozzle 114 to the mold assembly 150 is in a substantially flowable state.

[0033] The temperature of the raw material can be chosen to allow the plastic material to be injected into the mold assembly in a melted state. The temperature can vary depending on the material. For instance, the temperature of the plastic material inside the barrel may be 260 - 320 °C.

[0034] The clamping unit 170 supports the mold assembly 150. The clamping unit 170 has a fixed platen 171 and a moving platen 172. The moving platen 172 can be actuated by an actuator 173 to move the moving platen 172 relative to the fixed platen 171.

[0035] The mold assembly 150 has a fixed portion 158 and a movable portion 159. A component mold cavity 151 is defined between the fixed portion 158 and the movable portion 159. The fixed portion 158 is attached to the fixed platen 171 and the movable portion 159 is attached to the moving platen 172. In some cases, the mold assembly 150 may comprise several fixed portions and movable portions.

[0036] The nozzle 114 of Figure 1 is fluidly connected to a runner 136 of the mold assembly 150, and the runner 136 is fluidly connected to a gate 135. The gate 135 is fluidly connected to the component mold cavity 151.

[0037] Figure 2 schematically illustrates a cross-section view of an injection molding system 100 according to one example. Figure 3 schematically illustrates a perspective and partial view of the mold assembly 150 of the example of Figure 2.

[0038] The injection molding system 100 of Figure 2 is configured to inject an injection molded component. The injection molding system 100 comprises the plastic material feeding mechanism 110 to feed the mold assembly 150 with plastic material. The mold assembly 150 could be supported by the clamping unit 170 of Figure 1.

[0039] In the examples of Figures 2 and 3, the mold assembly 150 comprises a feeding portion 130 and the component mold cavity 151. The feeding portion 130 is arranged to provide a fluid communication between the plastic material feeding mechanism 110 and the component mold cavity 151. The nozzle 114 is in fluid communication with the feeding portion 130. The fixed portion 158 and the movable portion 159 of the mold assembly 150 are in a coupled condition to form the component mold cavity 151. Depending on the case the feeding portion 130 may be associated with the fixed portion 158 or the movable portion 159.

[0040] The component mold cavity 151 may comprise a shape corresponding to the shape of the injection molded component to be formed, e.g. a finished component.

[0041] As can be seen in Figures 2 and 3, the component mold cavity 151 comprises a component mold cavity cross-section extending between an inlet portion 152 and an end portion 153. The component mold cavity cross-section spans a component mold cavity length 154, see Figure 3. Thus, an inlet portion length and an end portion length can be also defined. The component mold cavity length 154 has been illustrated in Figure 3 as an arrow.

[0042] The feeding portion 130 comprises a feeding chamber 131 which is configured for feeding the component mold cavity 151 with the plastic material 111. The feeding chamber 131 of Figure 3 comprises a generally elongated configuration.

[0043] The feeding chamber 131 comprises a feeding outlet 132 in fluid communication with the inlet portion 152 of the component mold cavity 151 . As can be seen in the attached Figures, the feeding outlet 132 spans a feeding outlet length and the inlet portion length corresponds to the feeding outlet length. A height of the cross-section of the feeding outlet 132 may be substantially the same as the height of the cross-section of the inlet portion 152.

[0044] The feeding portion 130 also comprises a channel system 133 for receiving the plastic material 111 from the plastic material feeding mechanism 110 and distributing the plastic material 111 in the feeding chamber 131. The feeding chamber 131 may comprise a feeding inlet 134 to receive the plastic material from the channel system 133.

[0045] As can be seen in the examples of Figure 2 and 3, the feeding outlet 132 extends to the inlet portion 152. This way, the plastic material can flow from the feeding outlet 132 towards the inlet portion 152. In some cases, a projection 140 can be arranged between the feeding outlet 132 and the inlet portion 152. The projection 140 may help to produce a corresponding slot or recess in the finished component. The slot may help to separate the finished component from the solidified plastic material within the feeding chamber 131.

[0046] In some examples, an inner volume of the feeding portion 130 may be greater than an inner volume of the component mold cavity 151. The ratio between the inner volume of the feeding portion 130 and the inner volume of the component mold cavity 151 may be substantially 60 / 40. The inner volume of the feeding chamber 131 may represent a 30% of the total inner volume of the feeding portion 130 and the component mold cavity 151.

[0047] The plastic material feeding mechanism 110 is configured to supply a first amount of plastic material 111 to the channel system 133 at a first value of a material parameter. In some examples, the first amount of plastic material may be supplied at a first value of the material parameter to feed or fill the feeding chamber 131. A control unit 160 can manage the operation of the plastic material feeding mechanism 110 to supply the first amount of plastic material to the channel system 133 at the first value of the material parameter. The control unit 160 may command the extruder 113 to feed the mold assembly 150 at the first value of the material parameter. The control unit 160 may also command the nozzle 114 to supply the first amount.

[0048] The plastic material feeding mechanism 110 is further configured to supply a second amount of plastic material to the channel system 133 at a second value of the material parameter when a predetermined portion of the first amount of plastic material is built- up in the feeding chamber 131 to force the predetermined portion of the first amount of plastic to flow towards the end portion 153 of the component mold cavity 151. The control unit 160 can manage the operation of the plastic material feeding mechanism 110 to supply the second amount of plastic material to the channel system 133 at the second value of the material parameter. The control unit 160 may command the extruder 113 to feed the mold assembly 150 at the second value of the material parameter. The control unit 160 may also command the nozzle 114 to supply the second amount.

[0049] Therefore, the control unit 160 may be configured to control or manage operation of parts of the injection molding system 100. In examples, the control unit is configured to command devices of the system 100. According to some examples, the control unit 160 may control the operation of the heater, the ram or rotating screw, and / or the nozzle. The control unit 160 may also control filling operation of the mold assembly 150.

[0050] The control unit 160 has been illustrated in Figure 2 attached to the plastic material feeding mechanism 110 for the sake of clarity. However, the control unit 160 may be separated from the plastic material feeding mechanism 110. The control unit 160 may be in data communication with the rest of the injection molding system 100. The control unit 160 may be remotely placed from the rest of the injection molding system 100.

[0051] The control unit 160 may comprise machine-readable instructions that include predetermined operation parameters such as timing, flow rates, pressures, temperatures, plastic material volumes, etc. The control unit 160 may be configured to dynamically adapt the operation parameters to particular operation conditions of the system 100.

[0052] In some examples, the control unit 160 may command the operation of the plastic material feeding mechanism 110 based on the predetermined operation parameters. In these examples, the control unit 160 comprises an open-loop architecture.

[0053] In some examples, the system 100 may comprise a plurality of sensors arranged in different parts of the system 100 to provide the control unit with operation data of those different parts. The sensors may be arranged in the plastic material feeding mechanism 110 and / or the mold assembly 150. For example, the sensors may comprise pressure sensors, temperature sensors, flow rate sensors. The control unit 160 may command the operation of the plastic material feeding mechanism 110 based on the feedback received from the sensors. The control unit 160 may command the plastic material feeding mechanism 110 at a starting point based on the predetermined operation parameters. Then, the control unit 160 may be configured to dynamically adapt the operation parameters over the time depending on the received feedback. In these examples, the control unit 160 comprises a closed-loop architecture.

[0054] The material parameter may comprise at least one of pressure, temperature, or speed. The speed may refer to flow rate. The first and second values may be different from each other.

[0055] Figure 4A schematically illustrates a longitudinal-section view of the mold assembly 150 in which a predetermined portion of the first amount of plastic material is built-up in the feeding chamber 131 according to one example. Figure 4B schematically illustrates a longitudinal-section view of the mold assembly of Figure 4A in which the predetermined portion of plastic material is pushed from the feeding chamber 131 to the component mold cavity 151 according to one example.

[0056] In the example of Figure 4A, the feeding chamber 131 is substantially full so the predetermined portion of the first amount of plastic material may correspond substantially to the inner volume of the feeding chamber 131. However, the predetermined portion of the first amount of plastic material could correspond to a part of the overall volume of the feeding chamber 131 .

[0057] As the plastic material accumulates in the feeding chamber 131 to form the predetermined portion of the first amount of plastic, a smooth and homogeneous mass of plastic material may flow towards the end portion 153. The predetermined portion of the first amount of plastic material may be uniformly distributed in the feeding chamber 131. Weld lines may be substantially avoided in the finished plastic component.

[0058] The single front flow 117 formed in the feeding chamber 131 may be moved towards the end portion 153 of the component mold cavity 151.

[0059] According to some examples, the second amount of plastic material may be supplied at the second value of the material parameter when the feeding chamber 131 is substantially full.

[0060] When the material parameter comprises pressure, the second value of pressure may lower than the first value of pressure. In examples, the first amount may be lower or smaller than the second amount. A first pressure may involve that the plastic material to feed the feeding chamber may be moved at a corresponding first speed and / or first flow rate. A second pressure may involve that the plastic material to feed the feeding chamber may be moved at a corresponding second speed and / or second flow rate.

[0061] Figure 5 schematically illustrates a channel system 133 according to one example. The channel system 133 of this example comprises a plurality of gates 135 arranged on the feeding inlet 134. The gates 135 are positioned so as to exit into the feeding chamber 131. The plurality of gates 135 may be arranged along the length of the feeding chamber 131. The channel system 133 of Figure 5 comprises a sprue 138 feeding a plurality of runners 136 and sub-runners 137 to conduct the plastic material to the plurality of gates 135. In non-illustrated examples, the channel system 133 may comprise a plurality of runners 136 and may be void of sub-runners 137. The number of runners, sub-runners, and / or gates may vary depending on the case. The sprue 138 may receive the plastic material from the nozzle 114.

[0062] In examples, each runner or sub-runner may be divided into a number of sub-runners at a stage. For instance, a runner or sub-runner may be divided into two or more subrunners. The distance between adjacent sub-runners may vary at every stage. If a runner or sub-runner at a preceding stage is divided into two sub-runners at a subsequent stage, then the distance between adjacent sub-runners at the subsequent stage may be substantially a half the distance between runners or sub-runners at the preceding stage.

[0063] The channel system 133 of Figures 2 and 3 has been schematically illustrated. The gate 135 illustrated in Figures 2 and 3 may comprise the plurality of gates 135 of the example of Figure 5.

[0064] Figure 6 schematically illustrates a partial view of the feeding portion 130 according to one example. In Figure 6, the feeding chamber 131 comprises a main region 145 and a plurality of diffusers 139. The diffusers 139 are provided between the gates 135 and the main region 145. The diffusers 139 comprises a generally triangular or fan shape. The diffusers 139 are arranged so that the gates are connected to the narrow portion of the diffuser and the wide portion of the diffuser is connected to the main region 145.

[0065] The feeding chamber 131 may comprise the main region 145 even in the examples without diffusers 139.

[0066] In the example of Figure 6, the plurality of diffusers is arranged along the length of the feeding chamber 131. The diffusers are positioned adjacent to each other, in such a way that the wide portions of the diffuser are next to each other. Thus, a sawtooth configuration can be defined by the diffusers.

[0067] In some non-illustrated examples, the diffusers can be arranged along the length of the feeding chamber 131 leaving a distance between two adjacent diffusers. In these examples, there is a distance between the wide portions of the diffusers.

[0068] The plastic material 111 may be received from the gate 135, either at the first value of the material parameter or the second value of the material parameter. The plastic material 111 enters the narrow portion of the diffuser. Then, the plastic material can reach the main region 145 through the feeding inlet 134. The smooth and uniform mass of plastic material can be formed in the main region 135. In the case of the first amount of plastic material, the predetermined portion of the first amount can be stored, formed, built-up or accumulated in the main region 145. The single flow front can be formed at the first value of the material parameter. When the plastic material feeding mechanism 110 is operated to feed the second amount of plastic material at the second value of the material parameter, the plastic material can enter the diffusers 139 to push or move the predetermined portion of the plastic material to the end portion 153.

[0069] The length and the height of the main region 145 may correspond to the length and the height of the inlet portion 152. The width 146 of the main region 145 may be defined between the wide portion of the diffuser and the feeding outlet 132. In the cases wherein there is no diffuser, the width 146 of the main region 145 may be defined between the gate 135 and the feeding outlet 132.

[0070] The predetermined portion of the first amount may be substantially the same as the inner volume of the main region 145. In some examples, the predetermined portion of the first amount may be substantially a part of the inner volume of the main region 145.

[0071] The main region 145 may comprise a generally rectangular-shaped configuration. This rectangular shape can be seen in the example of Figure 6. In some examples, the main region 145 may comprise a generally arc-shaped configuration.

[0072] The shape of the component mold cavity 151 may vary depending on the shape of the component to be formed. For example, in Figure 3, the component mold cavity 151 comprises a rectangular cross-section. In Figure 7, the component mold cavity 151 comprises a U-shaped cross-section.

[0073] The component mold cavity 151 of Figure 7 comprises a first side 155 and a second side 156. The component mold cavity 151 of Figure 7 further comprises a connecting portion 157 to connect the first side 155 and the second side 156. The first side 155, the second side 156, and the connecting portion 157 form the generally U-shaped cross-section of the component mold cavity 151 of Figure 7. In this case, the first side comprises the inlet portion 152 and the second side comprises the end portion 153.

[0074] In some non-illustrated examples, the component mold cavity 151 may comprise a generally annular configuration. In this case, the length of the component mold cavity 151 includes the length of the circumference. The feeding chamber 131 may comprise a generally annular configuration as well. The plurality of gates 135 may be arranged around the generally annular configurated feeding chamber 131.

[0075] The plastic material of the present disclosure may comprise at least one of polypropylene, polyethylene, polyamide, polyetheretherketone, and / or the combination thereof.

[0076] The plastic material may comprise a thermoplastic or a thermoset material.

[0077] The plastic material of the present disclosure may comprise a filler. The filler may provide the plastic material with particular features. Some examples of filler may comprise talc, calcium carbonate, carbon black, silica, titanium dioxide, aluminum oxide, and / or the combination thereof.

[0078] The plastic material may comprise fiber reinforced plastic material. A fiber reinforced plastic material may have improved mechanical features compared to a non-reinforced plastic material. The fibers may provide, at least, improved stiffness and / or strength.

[0079] In examples of the present disclosure, the fiber reinforced plastic material may comprise carbon fibers, glass fiber, and / or aramid fibers. The length of the fibers may vary depending on the case. In some cases, the fibers may be shorter than 20 mm, more particularly shorter than 10 mm, and even more particularly shorter than 1 mm.

[0080] The fibers may be randomly dispersed in the plastic material introduced in the feeding chamber. However, when the mass of plastic material inside the feeding chamber 131 is pushed out towards the end portion 153, the fibers may be arranged aligned in the direction of the single front flow. The fibers may become uniformly distributed in the single front that moves towards the end portion 153. The average orientation of the fibers may be substantially aligned with a direction between the inlet portion 152 and the end portion 153.

[0081] As the fiber-reinforced plastic material may comprise anisotropic mechanical behavior, the fibers arranged substantially aligned in the direction of the single front flow inside the component mold cavity may improve the mechanical behavior of the finished component. The fibers may represent less than 40% w / w of the first amount or the second amount.

[0082] In some examples, the fibers may represent less than 30% w / w.

[0083] In some examples, the plastic material may comprise fiber unreinforced plastic material.

[0084] Figure 8 schematically illustrates a view of the control unit 160 of a system according to one example of the present disclosure. The control unit 160 may comprise a controller 161. Controller 161 may be a processor, a chip, a computational device, or processing resources that execute sequences of machine-readable instructions contained in a memory. Controller 161 performs operations on data. The memory may be a non-transitory machine-readable storage medium 162. As can be seen in Figure 8, the non-transitory machine-readable storage medium 162 is coupled to the controller 161. Examples of a non-transitory machine-readable storage medium may include a memory device, a floppy disk, a compact disk (CD), a digital versatile disk (DVD), a USB drive, a computer memory, a read-only memory, or other devices that may store computer code.

[0085] The machine-readable instructions may comprise a computer program(s) in the form of source code, object code, a code intermediate source, and object code such as in partially compiled form, or in any other form suitable for use in implementing the methods according to the present disclosure.

[0086] Figure 9 is a block diagram of a method for forming an injection molded component from a plastic material according to an example of the present disclosure. An injection molding system 100 for injecting an injection molded component according to the examples disclosed herein, may be used in method 200.

[0087] At block 210, providing an injection molding system 100 according to any of the examples disclosed herein is represented.

[0088] Method 200 further comprises supplying the first amount of plastic material to channel system 133 at the first value of the material parameter, as represented at block 220. The plastic material feeding mechanism 110 may be actuated to supply the first amount of plastic material at the first value of the material parameter to fill or feed the feeding chamber 131. The first value of the material parameter may be chosen depending on the case. In the examples in which the material parameter comprises pressure, the first pressure may be within the 85-130 MPa range.

[0089] Method 200 further comprises, as represented at block 230, supplying a second amount of plastic material to the channel system 133 at a second value of the material parameter when the predetermined portion of the first amount of plastic material is built-up in the feeding chamber 131 to force the predetermined portion of the first amount of plastic to flow towards the end portion 153 of the component mold cavity 151. The plastic material feeding mechanism 110 may be actuated to supply the second amount of plastic material. The second value of the material parameter may be chosen depending on the case. In the examples in which the material parameter comprises pressure, the second pressure may be within the 70-115 MPa range. The second pressure may be lower than the first pressure.

[0090] The material parameter may be varied from the first value to the second value in a stepped way or continuously. The plastic material feeding mechanism 110 may be configured to vary from the first value of the material parameter to the second value of the material parameter in a stepped way or continuously.

[0091] Flow of plastic material between the first amount and the second amount may be paused during a predetermined period. The plastic material feeding mechanism 110 may be configured to stop feeding plastic material during a predetermined period between the first amount and the second amount.

[0092] The temperature of the plastic material of the single front from the inlet portion 152 to the end portion 153 may be within the range of 260 - 310 °C. This range may allow the plastic material to reach the end portion 153 at suitable flow conditions.

[0093] The first amount and the second amount may be chosen depending on the inner volume of the mold assembly 150. The first amount may be lower than the second amount. However, the first amount may be larger or the same as the second amount.

[0094] In some examples, supplying 230 the second amount of plastic material may comprise introducing plastic material into the feeding chamber 131 to push the plastic material out of the feeding chamber 131 towards the end portion 153. The plastic material passes through the inlet portion 152 before reaching the end portion 153. The second amount of plastic material may be supplied at the second value of the material parameter when the feeding chamber 131 is full. In the examples wherein the feeding chamber 131 comprises the main region 135, the second amount may be supplied when the main region 135 is substantially full.

[0095] According to some examples, supplying a first amount of plastic material and / or a second amount of plastic material to the channel system may comprise injecting the plastic material to the channel system.

[0096] The method 200 may further comprise obtaining an intermediate injection molded component from the plastic material. The intermediate injection molded component may comprise a mold cavity component portion formed at the component mold cavity and a feeding chamber component portion formed at the feeding chamber. The intermediate injection molded component can be seen in the example of Figure 4A. In some examples, the intermediate injection molded component could comprise the mold cavity component portion, the feeding chamber component portion, and a channel system component portion. The channel system component portion may be formed, at least partially, at the channel system.

[0097] The feeding chamber component portion of the intermediate injection molded component may be removed to obtain the injection molded component. Removing the feeding chamber component portion may comprise cutting or separating the mold cavity component portion from the feeding chamber component portion. The projection 140 of the system 100 may help to produce a corresponding slot in the intermediate injection molded component. The slot may help to separate the mold cavity component portion from the feeding chamber component portion.

[0098] The obtaining an intermediate injection molded component may comprise hardening the plastic material. The plastic material may be substantially solidified during a predetermined period, and under a certain temperature. Obtaining the intermediate injection molded component may further comprise opening the mold assembly 150. This way, the hardened intermediate injection molded component can be extracted from the mold assembly 150.

[0099] In some examples, supplying 230 a second amount of plastic material may comprise providing the component mold cavity 151 with an insert. The insert may help to achieve a predetermined shape of the finished component. In some examples, the insert may comprise a pre-formed member and / or a tape. The pre-formed member and / or the tape can be made up of various materials such as metal, plastics, fibers, or any combination thereof. Incorporating inserts such as the pre-formed member or the tape may significantly increase the structural integrity, stiffness, or wear resistance of the component. Therefore, the pre-formed member or tape can improve the mechanical properties of the component.

[0100] The mold assembly 150 can be opened to position the insert within the component mold cavity 151. This can be done manually or automatically, for example, by robotic arms. The mold assembly 150 may have features to hold the insert in place, preventing the insert from moving during injection of plastic material into the component mold cavity 151.

[0101] Once the insert is positioned within the component mold cavity 151 , the mold assembly 150 can be closed. The plastic material can be injected into the feeding chamber and supplied to the mold cavity from the feeding chamber according to any of the examples discussed herein. This way, an overmolding of the insert can be performed.

[0102] The pre-formed member or tape can be integrated into the intermediate injection molded component and so the component.

Claims

CLAIMS1 . An injection molding system for injecting an injection molded component comprising: a plastic material feeding mechanism; a mold assembly comprising: a component mold cavity comprising a component mold cavity crosssection extending between an inlet portion and end portion; and wherein the component mold cavity cross-section spans a component mold cavity length defining an inlet portion length and an end portion length; a feeding portion comprising: a feeding chamber for feeding the component mold cavity with plastic material, wherein the feeding chamber comprises a feeding outlet in fluid communication with the inlet portion of the component mold cavity, wherein the feeding outlet spans a feeding outlet length; wherein the inlet portion length corresponds to feeding outlet length; a channel system for receiving plastic material from the plastic material feeding mechanism and distributing the plastic material in the feeding chamber; and wherein the plastic material feeding mechanism is configured to: supply a first amount of plastic material to the channel system at a first value of a material parameter; and supply a second amount of plastic material to the channel system at a second value of the material parameter when a predetermined portion of the first amount of plastic material is built-up in the feeding chamber to force the predetermined portion of the first amount of plastic to flow towards the end portion of the component mold cavity.

2. The system according to claim 1 , wherein the feeding outlet extends to the inlet portion.

3. The system according to any of claims 1 - 2, comprising: a projection arranged between the feeding outlet and the inlet portion.

4. The system according to any of claims 1 - 3, wherein the feeding chamber comprises a feeding inlet to receive the plastic material from the channel system.

5. The system according to claim 4, wherein the channel system comprises a plurality of gates arranged on the feeding inlet.

6. The system according to claim 5, wherein the plurality of gates is arranged along the length of the feeding chamber.

7. The system according to any of claims 5 - 6, wherein the channel system comprises a plurality of runners and sub-runners to conduct the plastic material to the plurality of gates.

8. The system according to any of claims 1 - 7, wherein the plastic material feeding mechanism comprises: a hopper to receive the plastic material to be injected, an extruder that drives and melts the plastic material fed by the hopper; and a nozzle associated with the extruder and configured to control the passage of plastic material from the extruder into the mold assembly.

9. The system according to any of claims 1 - 8, wherein the component mold cavity comprises a rectangular cross-section.

10. The system according to any of claims 1 - 9, wherein the component mold cavity comprises a U-shaped cross-section.

11. The system according to claim 10, wherein the component mold cavity comprises a first side and a second side and a connecting portion to connect the first side and the second side, the first side comprising the inlet portion and the second side comprising the end portion.

12. The system according to any of claims 1 - 11 , wherein the component mold cavity comprises a generally annular configuration.

13. The system according to claim 12, wherein the length of the component mold cavity comprises the length of circumference.

14. The system according to any of claims 1 - 11 , wherein the feeding chamber comprises a generally elongated configuration.

15. The system according to any of claims 1 - 14, wherein an inner volume of the feeding portion is greater than an inner volume of the component mold cavity.

16. The system according to claim 15, wherein the ratio between an inner volume of the feeding portion and an inner volume of the component mold cavity is 60 / 40.

17. The system according to any of claims 15-16, wherein the inner volume of the feeding chamber represents 30% of the total inner volume of the feeding portion and the component mold cavity.

18. The system according to any of claims 1 - 17, wherein a height of the cross-section of the feeding outlet is the same as the height of the cross-section of the inlet portion.

19. The system according to any of claims 1 - 18 wherein the second amount of plastic material is supplied at the second value of the material parameter when the feeding chamber is full.

20. The system according to any of claims 1 - 19, wherein the second value of the material parameter is lower than the first value of the material parameter.21 . The system according to any of claims 1 - 20, wherein the first amount is lower than the second amount.

22. The system according to any of claims 1 - 21 , wherein the component mold cavity comprises a shape corresponding to the shape of the injection molded component to be formed.

23. The system according to any of claims 1 - 22, wherein the predetermined portion of the first amount of plastic material is uniformly distributed in the feeding chamber.

24. The system according to any of claims 1 - 23 wherein the material parameter comprises pressure.

25. The system according to any of claims 1 - 23 wherein the material parameter comprises temperature.

26. The system according to any of claims 1 - 23, wherein the material parametercomprises speed or flow rate.

27. A method for forming an injection molded component from a plastic material, comprising: providing an injection molding system according to any of claims 1 - 26; supplying a first amount of plastic material to the channel system at a first value of a material parameter; supplying a second amount of plastic material to the channel system at a second value of the material parameter when a predetermined portion of the first amount of plastic material is built-up in the feeding chamber to force the predetermined portion of the first amount of plastic to flow towards the end portion of the component mold cavity.

28. The method according to claim 27, wherein supplying a second amount of plastic material comprises introducing plastic material into the feeding chamber to push the plastic material out of the feeding chamber towards the end portion.

29. The method according to any of claims 27 - 28, wherein the plastic material comprises fiber reinforced plastic material.

30. The method according to claim 29, wherein the fiber reinforced plastic material comprises carbon fibers.

31. The method according to any of claims 27 - 30, wherein the second amount of plastic material is supplied at the second value of the material parameter when the feeding chamber is full.

32. The method according to any of claims 27 - 31 , wherein the second value of the material parameter is greater than the first value of the material parameter.

33. The method according to any of claims 27 - 32, wherein the first amount is lower than the second amount.

34. The method according to any of claims 27 - 33, wherein the predetermined portion of the first amount of plastic material is uniformly distributed in the feeding chamber.

35. The method according to any of claims 27 - 34, wherein the plastic material comprises a filler.

36. The method according to any of claims 27 - 35, wherein supplying a second amount of plastic material comprises providing the component mold cavity with an insert.

37. The method according to claim 36, wherein the insert comprises a pre-formed member and / or a tape.

38. The method according to any of claims 27 - 37, wherein supplying a first amount of plastic material and / or a second amount of plastic material to the channel system comprises injecting the plastic material to the channel system.

39. The method according to any of claims 27 - 38, comprising: obtaining an intermediate injection molded component from the plastic material, wherein the intermediate injection molded component comprises a mold cavity component portion formed at the component mold cavity and a feeding chamber component portion formed at the feeding chamber; removing the feeding chamber component portion of the intermediate injection molded component to obtain the injection molded component.

40. The method according to claim 39, wherein removing the feeding chamber component portion comprises cutting or separating the mold cavity component portion from the feeding chamber component portion.41 . The method according to any of claims 39 - 40, wherein obtaining an intermediate injection molded component comprises hardening the plastic material.

42. The method according to any of claims 39 - 41 , wherein obtaining an intermediate injection molded component comprises opening a mold assembly.

43. The method according to any of claims 39 - 42, wherein the material parameter comprises pressure.

44. The method according to any of claims 39 - 42, wherein the material parameter comprises temperature.

45. The method according to any of claims 39 - 42, wherein the material parameter comprises speed or flow rate.

46. An injection molded component obtained by the method according to any of claims

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