Injection molding device and method for injection molding with an injection molding device

Abstract

Including injection molding device: - a hot runner manifold (30); - at least one tool plate (34) and at least one bearing insert (33); - at least one mold cavity (35) having two sprue openings (65, 66), - at least one first hot runner nozzle (21) for lateral pouring and at least one second hot runner nozzle (22) for lateral pouring, which are connected to the hot runner manifold (30) and are arranged such that each hot runner nozzle (21, 22) can individually and independently of the melt flow through other hot runner nozzles (21, 22) direct melt to one of the at least two pouring ports (65, 66), wherein each hot runner nozzle (21, 22), which has a single nozzle tip (61, 62) and a nozzle melt channel (27) through which melt is directed to and through the nozzle tip (61, 62), is arranged in a bearing insert (33) such that its nozzle tip (61, 62) is positioned with respect to the corresponding pouring port (65, 66); - at least one first needle valve arrangement (63, 67, 69) associated with the first hot runner nozzle (21) and at least one second needle valve arrangement (64, 68) associated with the second hot runner nozzle (21), each needle valve arrangement comprising a valve needle (63, 64) adjustable along a first axis (63a, 64a) and an actuating element (67, 68) adjustable along a second axis (67a, 68a), the first axis (63a, 64a) being arranged at an angle to the second axis (67a, 68a), and the actuating element (67, 68) and the valve needle (63, 64) cooperating to control the amount of melt that can be guided through the nozzle tip (61, 62) and through the corresponding sprue opening (65, 66) into a mold cavity (35); - at least one first actuating device (41) and at least one second actuating device (42) which are associated with the needle valve assemblies (71, 72), wherein the first actuating device (41) has a first drive mechanism (43) which is connected to the actuating element (67) of the first hot runner nozzle (21), and the second actuating device (42) has a second drive mechanism (44) which is connected to the actuating element (68) of the second hot runner nozzle (22); and - at least one control device (80), which is operated automatically or manually, which is connected to the at least one first and the at least one second actuating device (41, 42) and has at least one position control function for adjusting the position of the valve needle (63) of the at least one first hot runner nozzle (21) independently of or simultaneously with the position of the valve needle (64) of the at least one second hot runner nozzle (22), in order to enable and prevent a guided entry of melt into at least one mold cavity (35) via a hot runner nozzle (21, 22), while preventing a guided entry of melt into at least one other mold cavity (35) via another hot runner nozzle (21, 22).

Description

[0001] The present invention relates to an injection molding apparatus comprising a hot runner manifold, a mold plate, at least two separate mold cavities, at least one first hot runner nozzle, and at least one second hot runner nozzle connected to the hot runner manifold and arranged such that each hot runner nozzle can individually and independently supply melt to the at least two gates. The invention particularly relates to hot runner mold tools for side gates, hot runner nozzles with valve needles, and an injection molding method for hot runner injection molding using hot runner nozzles with side needle valves.

[0002] Hot runner molds for side gating and injection molding processes that use hot runner nozzles for side gating are known in the art.

[0003] Hot runner injection molds that use hot runner nozzles for side gating by means of valve pins (side gating hot runner nozzles) and injection molding processes that use hot runner injection molds with hot runner nozzles for side gating are also known. The following publications are cited as examples: US 7,322,817 B2 by inventor Hans-Peter Männer and US 7,470,123 B2 by Swen Spuller, WO 2010 / 012 796 A1 by Braun, US 7,658,606 B2 by Klobucar, US 6,245,279 B1 by Kalemba, US 7,658,605 B2 by Fairy, US 41,648 E by Olaru, and JP H07-144,347 A and JP H11-277,573 A.

[0004] In side-gating applications, there are situations in which the melt flow from a first nozzle tip into a first mold cavity must be blocked, while simultaneously maintaining the melt flow from a second nozzle tip into a second mold cavity. This is very important because it allows some mold cavities to be filled while mold filling in others, or only in one other mold cavity, can be stopped or shut down. In this way, the production process of an injection molding machine is not completely stopped; only the output is reduced until the cause of the failure of one or more nozzles can be eliminated.

[0005] US Pat. No. 7,803,306 B2 to Babin demonstrates this problem and presents a solution for interrupting melt flow into a side-gating hot runner nozzle. There is a need to improve the design, characteristics, and maintenance of hot runner injection molds that utilize side-gating valve pin hot runner nozzles, as well as to improve the processes used in such applications.

[0006] There is also a need to control or completely block the melt flow through one of a plurality of gates or through one of a plurality of nozzle tips of a hot runner mold that uses hot runner nozzles for side gating, and to improve the methods used in such applications.

[0007] Publications US 4 810 184 A, DE 10 2004 031 546 A1, and US 2012 / 0 211 921 A1 describe injection molding apparatus and methods for injection molding for mold cavities with multiple gates. Korean Patent Application KR 10 2012 0 100 524 A relates to an injection molding apparatus with multiple hot runner nozzles, wherein at least two hot runner nozzles are controlled simultaneously.

[0008] The invention is therefore based on the object of controlling the melt flow through at least one of a plurality of hot runner nozzles with valve needles for side injection (hot runner nozzles for side injection) independently of the melt flow through other hot runner nozzles.

[0009] This problem is solved by the teaching of the independent claims of the invention. Further developments of the invention form the subject matter of the dependent claims.

[0010] To achieve this object, an injection molding apparatus is proposed, comprising a hot runner manifold, at least one tool plate, and at least one bearing insert. The injection molding apparatus further comprises at least one mold cavity having at least two sprue openings and at least one first hot runner nozzle and at least one second hot runner nozzle, which are connected to the hot runner manifold and arranged such that each hot runner nozzle can guide melt to one of the at least two sprue openings individually and independently of the melt flow through other hot runner nozzles. Each hot runner nozzle, which in particular has a single nozzle tip and a nozzle melt channel through which melt is guided to and through the nozzle tip, is arranged in a bearing insert such that its nozzle tip is positioned relative to the corresponding sprue opening.

[0011] The injection molding apparatus further comprises at least one first needle valve assembly associated with the first hot runner nozzle and at least one second needle valve assembly associated with the second hot runner nozzle, each of the needle valve assemblies comprising a valve needle adjustable along a first axis and an actuating element adjustable along a second axis, the first axis being arranged at an angle relative to the second axis, and the actuating element and the valve needle cooperating to control the amount of melt that can be guided through the nozzle tip and through the corresponding gate into a mold cavity.

[0012] The injection molding apparatus according to the invention additionally comprises at least one first actuating device and at least one second actuating device, which are assigned to the needle valve assemblies, wherein the first actuating device comprises a first drive mechanism connected to the actuating element of the first hot runner nozzle, and the second actuating device comprises a second drive mechanism connected to the actuating element of the second hot runner nozzle. In an exemplary embodiment, the drive mechanism comprises a pneumatic cylinder. Such a pneumatic cylinder can have a position control function for adjusting the stroke length of the valve needle. In another development of the injection molding machine, the drive mechanism comprises an electric drive for driving the valve needle and for the position control function of the valve needle.

[0013] The invention thus discloses a hot runner injection molding device for side gating or injection molding, which utilizes a needle valve. The injection molding device has, in particular, a plurality of mold cavities, each mold cavity having at least two gate openings. In an exemplary embodiment, at least one mold core is arranged in the mold cavity, extending along a mold core axis.

[0014] In an exemplary embodiment, melt is introduced into each mold cavity by at least two hot runner nozzles connected to a hot runner manifold. The at least two hot runner nozzles are arranged such that they can separately and independently inject melt into each mold cavity through at least two gates.

[0015] In some applications, particularly those involving larger injection molded parts or shorter cycle times, three or four gates may be arranged on a single mold cavity, into which melt is introduced through three or four valve needle nozzles having side gates.

[0016] An exemplary injection molding apparatus has mold cavities of the same size, shape, or volume. However, it is also conceivable that the injection molding apparatus has mold cavities of different sizes, shapes, or volumes.

[0017] In an exemplary embodiment, the melt flows from the hot runner manifold through one or more hot runner nozzles to the at least one mold cavity, each nozzle having at least one nozzle tip arranged close to a gate of a mold cavity, which in particular has a plurality of gates.

[0018] The amount of melt and the opening and stopping of the melt discharge from the nozzle into the mold cavity are controlled in particular by an adjustable valve needle. In some exemplary embodiments of the nozzles, the valve needle is arranged outside a main melt channel arranged within the nozzle body of the nozzle. In other exemplary embodiments, the valve needle is integrally designed and adjustable in a direction of movement along the main melt channel of the nozzle. In other exemplary embodiments, the valve needle of each nozzle has two sections: a first valve needle section (main valve needle section) connected to a drive mechanism and interacting with a second valve needle section arranged close to the nozzle tip and close to the gate.

[0019] A further development of the injection molding device has at least two separate mold cavities.

[0020] The injection molding apparatus has at least one control device, which is operated in particular automatically or manually, which is connected to the at least one first and the at least one second actuating device and has at least one position control function for adjusting the position of the valve needle of the at least one first hot runner nozzle independently of or simultaneously with the position of the valve needle of the at least one second hot runner nozzle in order to guide melt into at least one mold cavity, in particular in order to enable and prevent a guided entry of melt into at least one mold cavity via one nozzle, while this prevents a guided entry of melt into at least one other mold cavity via the other nozzle.

[0021] In particular, the control device adjusts the position of the valve needle of the at least one first hot runner nozzle and / or the position of the valve needle of the at least one second hot runner nozzle in order to guide melt into at least one mold cavity through both of the at least one first and at least one second hot runner nozzle.

[0022] In another embodiment, the control device adjusts the position of the valve needle of the at least one first hot runner nozzle and / or the position of the valve needle of the at least one second hot runner nozzle such that melt is guided into at least one mold cavity only through one of the at least one first and at least one second hot runner nozzle.

[0023] In yet another embodiment of the injection molding apparatus, the control device is connected to the at least one first and the at least one second actuating device and has at least one position control function for adjusting the position of the valve needle of the at least one first hot runner nozzle independently of or simultaneously with the position of the valve needle of the at least one second hot runner nozzle in order to interrupt the supply of melt into at least one mold cavity.

[0024] An exemplary embodiment comprises such a control device, which in particular controls each of the three aforementioned states and thus the supply of melt into at least one mold cavity through at least two or at least one hot runner nozzle. In the same way, the supply of melt into at least one of the exemplary plurality of mold cavities can also be interrupted.

[0025] According to this aspect, it is possible by means of a control device, by positioning the valve needle in the hot runner nozzle, which has a needle valve, to reduce and / or adjust or regulate or even interrupt the supply of melt into an individual mold cavity through at least two lateral gates and in particular through two needle valve nozzles with lateral injection, by differently actuating a first hot runner nozzle with needle valve and the first valve needle connected thereto relative to the first gate, differently than a second hot runner nozzle with needle valve and the second valve needle connected thereto,that the positions of the first valve needle and the second valve needle can be selected for different filling processes for the same mold cavity or for different filling processes for filling the same mold cavity or for filling a plurality of mold cavities by means of at least two hot runner nozzles for each mold cavity.,

[0026] In an exemplary embodiment, in which at least one mold core extending along a mold core axis is arranged in the mold cavity, and in which two gate openings are arranged, for example, on opposite sides of the mold core, different flow velocities of the injected melt can lead to mold core displacement. The control device can adjust the opening of the valve openings and thus the flow rate of the melt from the nozzles so that mold core displacements or other effects caused by the flow rate of the melt through an injection nozzle can be adjusted.

[0027] It is possible to deactivate at least one of the at least two hot runner nozzles when at least two hot runner nozzles are used to fill a mold cavity. The gate is blocked, and the mold cavity is filled by lateral injection from the remaining at least one other hot runner nozzle. This may be necessary if one of a plurality of hot runner nozzles is damaged, resulting in a deterioration in the quality of the injection-molded part. Similarly, it may be necessary to block all hot runner nozzles involved in filling a mold cavity in a mold having a plurality of mold cavities, and to continue the injection molding process using only the other mold cavities.

[0028] If the number of hot runner nozzles used to fill a mold cavity is reduced, a longer injection time is required to fill the mold cavity using the remaining hot runner nozzles. For molds that have multiple cavities and at least one cavity must be filled by the fewer remaining hot runner nozzles after a hot runner nozzle is blocked, the mold filling of the cavities filled by two or more hot runner nozzles will end sooner than the filling of the cavities filled by a fewer number of hot runner nozzles. However, depending on the proportion of mold cavities that must be filled with a fewer number of hot runner nozzles, this may result in higher yield than completely stopping the filling of these cavities.

[0029] In another embodiment of the injection molding device, the position adjustment of the control device can be preset, in particular by programming. In a further exemplary embodiment, the position adjustment of the control device is automatically calculated and adjusted based on parameter values ​​supplied to this control device. In a further exemplary embodiment of the control device, its position adjustment can be manually preset and / or manually adjustable, in particular during operation of the injection molding device.

[0030] In an exemplary embodiment of the injection molding device, the at least two mold cavities have the same or different volumes and can have the same or different shapes.

[0031] A further aspect of the invention is a method for injection molding using an injection molding apparatus of the type described above, wherein, by means of a position control function, the position of the valve needle of the at least one first hot runner nozzle is adjusted independently of or simultaneously with the position of the valve needle of the at least one second hot runner nozzle such that all of the at least two valve needles open and close the respective gates of a mold cavity. In this operating state, in particular, all mold cavities are filled within one injection molding cycle, wherein the filling of individual mold cavities can be improved by adjusting the movement of one or more individual valve needles.

[0032] Simultaneously or temporarily, in the injection molding process, at least one gate of a mold cavity is blocked by the respective valve pin, while the at least one other valve pin continues to open and close the at least one other gate. This may be necessary if one of a plurality of hot runner nozzles is damaged, resulting in a deterioration in the quality of the produced injection-molded part. If the number of hot runner nozzles used to fill the mold cavity is reduced, a longer injection time is required to fill the mold cavity with the remaining hot runner nozzles.For molds with multiple cavities, where at least one cavity must be filled by the few remaining hot runner nozzles after one hot runner nozzle has been blocked, the filling of the cavities filled by two or more hot runner nozzles will stop sooner than the filling of the cavities filled by a smaller number of hot runner nozzles. However, depending on the proportion of cavities that must be filled with a smaller number of hot runner nozzles, this may result in higher yield than completely stopping the filling of these cavities.

[0033] Similarly, in the injection molding process, all gates of a mold cavity are simultaneously or temporarily blocked by the respective valve pins. Thus, one or more mold cavities are no longer used in the production process, and the injection molding process continues using only the other cavities. Depending on the number of mold cavities still being used in the molding process and the number of blocked cavities, it may be more advantageous to continue production with fewer cavities than to interrupt production to repair the injection system.

[0034] In a further development of the injection molding process, the control device provides signals to the actuating devices during each injection molding cycle to either a) to open and close all gates of a mould cavity simultaneously, or b) to open and close the gates of a mould cavity at different times, or c) to maintain at least two valve pins in the closed position for the same mold cavity to prevent melt flow into one mold cavity while melt flows into the other mold cavities. In this way, the control device serves to control the individual actuating devices and thus the individual valve pins of a nozzle.

[0035] For example, the signals provided by the control device are based on the molding process data. Suitable process data is acquired by sensors in the injection molding device and fed to the control device. Usable sensors include thermocouples, which are particularly located near or in the melt channel of the hot runner system (manifold and nozzle) or the mold cavity, pressure sensors located in the mold cavity, and other sensors that monitor the operation of the injection molding system. The sensors can be located at various points in the injection molding system and thus provide different information on the operating conditions. Suitable process data is also acquired by the control device itself, for example through feedback from the device units, such as the pressure of the melt to be injected or the time required for valve needle actuation or the duration of an injection molding cycle.

[0036] Similarly, the signals provided by the control system can be based on the quality of each casting, which is traced back to each mold cavity and gate. The quality of the casting, particularly weld lines or the completeness of the part, is an indicator of proper operation of the injection system.

[0037] Likewise, the signals provided by the control device can be based on an operator command entered into a control system of the injection molding machine and made available to the control device. For example, an operator who detects a need to block one or more valve pins can input this need into a corresponding control system of the injection molding machine and prevent melt flow through one or more individual nozzles and / or melt flow into one or more mold cavities while other mold cavities are in use.

[0038] Since each valve pin is individually controlled—for example, there is only one valve pin that needs to be actuated in a nozzle—the filling process of a mold cavity with at least two gates can be individually controlled. This makes it possible to adapt the filling process for parts with complex designs.

[0039] In conjunction with the figures, the following description presents further advantages, features and possible applications of the present invention.

[0040] Shown in: Fig. 1: a sectional view of a detail of an exemplary injection molding device in the area of ​​the injection mold; Fig. 2: an enlarged detail of the illustration from Fig. 1; Fig. 3: another enlarged detail of the illustration from Fig. 1 or Fig. 2; Fig. 4: another enlarged detail of the illustration from Fig. 1; Fig. 5: another enlarged detail of the illustration from Fig. 1 in the area of ​​the operating device; Fig. 6: a sectional view of a larger detail of an exemplary injection molding device in the area of ​​the injection device; Fig. 7: an enlarged detail of an exemplary injection molding device in the area of ​​the injection device, similar to Fig. 4; and Fig. 8: a sectional view of a detail of another exemplary injection molding device in the area of ​​the injection mold.

[0041] Fig. Figure 1 shows a detail of an exemplary injection molding apparatus in the field of injection molding according to an exemplary embodiment of the invention. The actuating device 40, which in the exemplary embodiment has a first pneumatic cylinder 41 and a second pneumatic cylinder 42, is shown in the upper part of the figure. The injection molding apparatus has a hot runner manifold 30 and a manifold plate 31.

[0042] A first hot runner nozzle 21 and a second hot runner nozzle 22 are arranged in the area of ​​the distributor plate 31 and in a bearing insert 32. The first hot runner nozzle 21 and the second hot runner nozzle 22 each have a first heating device 23 and a second heating device 24, as well as a first nozzle head 25 and a second nozzle head 26. The hot runner nozzles 21 and 22 are hot runner nozzles with needle valves and side gating (side-gating hot runner nozzles). The illustration also shows the mold core 36, which is arranged in the mold cavity 35.

[0043] Fig. 2 shows an enlarged detail from the illustration in Fig. 1 of an exemplary injection molding device in the area of ​​the injection mold. The detail shows approximately the area that Fig. 1 is circled. Fig. Figure 2 shows the mold core 36, its end region, shown at the top of the figure, and its mold core head 36a, which are mounted in the nozzle-side mold insert 37. When the casting tool is opened, the mold core 36 and the nozzle-side mold insert 37 remain on the distributor plate 31. The cooling channel 38 is arranged within the mold core 36, by means of which a coolant, in particular water, circulates through the interior of the mold core 36.

[0044] The nozzle heads 25 and 26 of the hot runner nozzles 21 and 22 are arranged in the nozzle-side mold insert 37. For axial positioning, a first bearing plate 25a and a second bearing plate 26a are arranged at the end of the nozzle head opposite the nozzle tip and support the nozzle head axially relative to the bearing insert 32.

[0045] Fig. 3 shows a further enlarged detail of the representation of an exemplary injection molding device in the area of ​​an injection molding tool from Fig. 1 or Fig. 2. The detail shows approximately the area that Fig. 2 is circled. The illustration shows the first nozzle tip 61 and the second nozzle tip 62, on which a first key surface 61a and a second key surface 62a are arranged. The key surfaces enable the nozzle tips 61, 62 to be mounted on the respective hot runner nozzles 21, 22.

[0046] The first valve needle 63 and the second valve needle 64 are adjustably arranged within the first nozzle tip 61 and the second nozzle tip 62. Fig. 3 shows the valve needles 63, 64 in a closed position of the hot runner nozzles for side injection 21, 22. The first gate 65 and the second gate 66 are each shown in front of the corresponding valve needle 63, 64.

[0047] A first insulating ring 28 is arranged on the first nozzle head 25, which, on the one hand, thermally insulates the heated hot runner nozzle 12 from the cooled mold insert 37. The insulating ring 28 also has a sealing function with respect to the mold insert 37 in such a way that the melt cannot penetrate along the nozzle head into the mold insert 37 during the injection process. The insulating ring 28 also serves to radially position the nozzle tip 61 in the mold insert 37 and, as a result, to position it relative to the gate opening 66. A second insulating ring 29 with the same properties as the first insulating ring 28 is arranged on the second nozzle head 26.

[0048] Fig. 4 also shows an enlarged detail of the illustration from Fig. 1, wherein in particular the first nozzle head 25 and the second nozzle head 26 of the first and second hot runner nozzles for side casting 21, 21 are each shown in section. The following description relates to the sectional view of the first hot runner nozzle 21, which is a mirror image of the second hot runner nozzle 22.

[0049] The valve needle 63 is adjustably arranged along a first axis 63a within the hot runner nozzle 21. An actuating element 67 is also adjustably arranged along a second axis 67a, which is perpendicular to the first axis 63a, so that movement of the actuating element 67 along the second axis 67a causes movement of the valve needle 63 along the first axis 63a. The arrangement of the valve needle 63 and the actuating element 67 is referred to as a needle valve assembly 71. A connecting element 69, which is part of the actuating element 67, provides the movement mechanism for the needle valve assembly 71. A nozzle melt channel 27, through which melt can be guided from the hot runner manifold 30 to the first nozzle tip 62, is arranged within the nozzle head 25.

[0050] Fig. 5 shows another enlarged detail of the illustration from Fig. 1 in the region of the actuating device 40. In the exemplary embodiment, this comprises a first pneumatic cylinder 41 and a second pneumatic cylinder 42. The first pneumatic cylinder 41 has a first actuating piston 43, and the second pneumatic cylinder 42 has a second actuating piston 44, each of which is connected to the first actuating element 67 and the second actuating element 68, respectively, and serves to actuate the hot runner nozzles with side gating 21, 22.

[0051] Fig. Figure 6 shows a sectional view of a larger detail of an exemplary injection molding apparatus in the area of ​​the injection device. This view shows two mold cavities 35, into which melt can be injected from two hot runner nozzles with side gating 21, 22. Fig. 6 further shows a control device 80, which is connected to the actuating devices 41, 42 of the needle valve assemblies 71, 72, in particular to control the movement of the valve needles 63, 64. The figures show an embodiment of a hot runner nozzle 21, 22 developed for lateral injection with lateral gates. In this case, the valve needles 63, 64 do not move in the opening / closing direction of the mold, but rather at a right angle to it. The nozzle body with the pneumatic system is arranged towards the mold. A pneumatically adjusted actuating element simultaneously actuates the valve needles 63, 64, which are arranged perpendicular to it.

[0052] High-viscosity materials require high pressure in the injection molding process. The exemplary embodiment features larger flow cross-sections, thus supporting the most stress-free processing of plastic. The hot runner nozzles 21, 22 also have a larger valve needle opening stroke to increase the flow cross-section in the hot runner nozzle, thereby reducing pressure loss and thus enabling the production of parts with greater weight and / or volume.

[0053] To achieve narrow temperature windows when processing plastics, the hot runner nozzle for side gating 21, 22 is divided into numerous structural parts, each configured with different insulating / conductive materials. In conjunction with additional active heating and control zones for each nozzle tip 61, 62 and optionally for the nozzle flange, an optimal temperature profile is achieved across the entire melt flow path.

[0054] To avoid weld line problems, for example, in larger syringe bodies, the exemplary embodiment shown provides two mold cavity 35 gates 65, 66 on the respective long sides of the casting. A dual hot runner with two single-point nozzles is used. This shortens the melt flow paths and improves the filling of the mold cavity 35 when producing longer tubular bodies.

[0055] Injecting along the long sides means that the exemplary syringe bodies are removed at a 90° angle relative to the valve needles 63, 64. During the sealing process, the needle is simply inserted into the casting by a few hundredths of a millimeter. To ensure that the valve needle does not scratch the surface of the nozzle body during removal, the needle undergoes a defined, short return stroke before the casting tool opens. The closing needle is therefore always positioned in the sprue opening to prevent uncontrolled leakage of the melt. Due to the return stroke movement, the valve needle, which is heated by friction during the injection process, is no longer in contact with the casting. This improves cooling of the gate on the casting and thus ensures a perfect surface, even if active cooling cannot be used in this area due to limited space.

[0056] The mold shown in the figures features a modular mold with two cavities and a quadruple hot runner system with four single-point nozzles. Interchangeable mold inserts allow for the production of castings of different sizes. Larger syringe bodies can be injection molded with two gates each, while smaller bodies can be molded with only one.

[0057] Fig. Figure 7 shows an enlarged detail of an exemplary injection molding device in the area of ​​the injection device, similar to Fig. 4, wherein in particular a first nozzle head 25 of the first hot runner nozzle 21 designed for lateral casting is shown in section. The function of the injection device from Fig. 7 corresponds to the function of the injection device from Fig. 4, which is described above.

[0058] The temperature sensors 48a, 48b are located in the injection device Fig. 7. A temperature sensor 48a is arranged near the gate 65, and another temperature sensor 48b is arranged near the nozzle nozzle 62. The signals from one or both of the temperature sensors 48a, 48b are provided, for example, to the control device 80, or, if applicable, are processed by another controller, and the output signals are provided to the control device 80 for further processing and, if applicable, for supplying signals to the respective actuating device to actuate or block the valve needle 63 of the hot runner nozzle 21.

[0059] Fig. Figure 8 shows a sectional view of a detail of another exemplary injection molding machine in the area of ​​the injection tool. Fig.8, only one hot runner nozzle 21 is shown on the opposite side of the mold cavity; a sensor device 49 is shown, which is arranged on the mold cavity. The sensor device 49 detects both temperature and pressure within the mold cavity. Depending on the type of sensor device 49, it is also possible to arrange the sensor device close to or in the mold cavity. Similarly—depending on the parameters to be detected—it is also possible to use a single sensor for temperature and pressure, or to detect additional parameters using additional individual or integrated sensor devices 49.The signals of the sensor device 49 are also made available, for example, to the control device 80 or, if applicable, are processed by a further controller and the output signal is made available to the control device 80 for further processing and, if applicable, for supplying signals to the respective actuating device in order to actuate or block the valve needle 63 of the hot runner nozzle 21. List of reference symbols 21 Hot runner nozzle 22 Hot runner nozzle 23 Heating device 24 Heating device 25 nozzle head 25a bearing plate 26 nozzle head 26a bearing plate 27 Nozzle melt channel 28 Insulating ring 29 Insulating ring 30 hot runner manifolds 31 Distribution plate 32 bearing insert 33 bearing insert 34 Tool plate 35 mold cavity 36 mold core 37 mold insert 38 cooling channel 40 Actuating device 41 Actuating device 42 Actuating device 43 actuating piston 44 actuating pistons 48a Temperature sensor 48b Temperature sensor 49 Sensor device 61 nozzle tip 61a Key surface 62 nozzle tip 62a key surface 63 valve needle 63a Axis 64 valve needle 65 Pouring opening 66 Pouring opening 67 Actuating element 67a Axis 68 Actuating element 68a Axis 69 Connecting element 71 Needle valve arrangement 72 Needle valve arrangement 80 Control device

Claims

[1] Injection molding device comprising: - a hot runner manifold (30); - at least one tool plate (34) and at least one bearing insert (33); - at least one mold cavity (35) having two sprue openings (65, 66), - at least one first hot runner nozzle (21) for side gating and at least one second hot runner nozzle (22) for side gating, which are connected to the hot runner manifold (30) and arranged such that each hot runner nozzle (21, 22) can individually and independently of the melt flow through other hot runner nozzles (21, 22) guide melt to one of the at least two sprue openings (65, 66), wherein each hot runner nozzle (21, 22), which has a single nozzle tip (61, 62) and a nozzle melt channel (27) through which melt is guided to and through the nozzle tip (61, 62), is arranged in a bearing insert (33) such that its nozzle tip (61, 62) is positioned relative to the corresponding sprue opening (65, 66); - at least one first needle valve arrangement (63, 67, 69) associated with the first hot runner nozzle (21) and at least one second needle valve arrangement (64, 68) associated with the second hot runner nozzle (21), wherein each of the needle valve arrangements comprises a valve needle (63, 64) adjustable along a first axis (63a, 64a) and an actuating element (67, 68) adjustable along a second axis (67a, 68a), wherein the first axis (63a, 64a) is arranged at an angle relative to the second axis (67a, 68a), and wherein the actuating element (67, 68) and the valve needle (63, 64) cooperate to control the amount of melt that can be guided through the nozzle tip (61, 62) and through the corresponding gate opening (65, 66) into a mold cavity (35) is; - at least one first actuating device (41) and at least one second actuating device (42) associated with the needle valve assemblies (71, 72), wherein the first actuating device (41) comprises a first drive mechanism (43) connected to the actuating element (67) of the first hot runner nozzle (21), and the second actuating device (42) comprises a second drive mechanism (44) connected to the actuating element (68) of the second hot runner nozzle (22); and - at least one control device (80) which is operated automatically or manually, which is connected to the at least one first and the at least one second actuating device (41, 42) and has at least one position control function for adjusting the position of the valve needle (63) of the at least one first hot runner nozzle (21) independently of or simultaneously with the position of the valve needle (64) of the at least one second hot runner nozzle (22) in order to enable and prevent a guided entry of melt into at least one mold cavity (35) via one hot runner nozzle (21, 22) while preventing a guided entry of melt into at least one other mold cavity (35) via another hot runner nozzle (21, 22). [2] Injection molding device according to claim 1, characterized by that it has at least two separate mold cavities (35). [3] Injection molding apparatus according to claim 1 or 2, characterized bythat the at least one control device (80) has at least one position control function for adjusting the position of the valve needle (63) of the at least one first hot runner nozzle (21) independently of or simultaneously with the position of the valve needle (64) of the at least one second hot runner nozzle (22) in order to guide melt through both of the at least one first and at least one second hot runner nozzle (21, 22) into at least one mold cavity (35). [4] Injection molding apparatus according to any one of the preceding claims, characterized byin that the at least one control device (80) has at least one position control function for adjusting the position of the valve needle (63) of the at least one first hot runner nozzle (21) independently of or simultaneously with the position of the valve needle (64) of the at least one second hot runner nozzle (22) in order to guide melt only through one of the at least one first and at least one second hot runner nozzle (21, 22) into at least one mold cavity (35). [5] Injection molding apparatus according to any one of the preceding claims, characterized by that the at least one control device (80) has at least one position control function for adjusting the position of the valve needle (63) of the at least one first hot runner nozzle (21) independently of or simultaneously with the position of the valve needle (64) of the at least one second hot runner nozzle (22) in order to interrupt the feeding of melt into at least one mold cavity (35). [6] Injection molding apparatus according to any one of the preceding claims, characterized by that the position adjustment of the control device (80) is preset, in particular by programming. [7] Injection molding apparatus according to any one of claims 1 to 5, characterized by that the position adjustment of the control device (80) is automatically calculated and adjusted based on parameter values ​​read into this control device (80). [8] Injection molding apparatus according to any one of the preceding claims, characterized by that the position adjustment of the control device (80) can be manually preset and / or manually adjustable, in particular during operation of the injection molding device. [9] Injection molding apparatus according to any one of the preceding claims 2 to 8, characterized bythat the at least two mold cavities (35) have the same or different volumes and / or the same or different shapes. [10] Method for injection molding with an injection molding device according to one of claims 1 to 9, characterized by that by means of the position control function, the position of the valve needle (63) of the at least one first hot runner nozzle (21) is adjusted independently of or simultaneously with the position of the valve needle (64) of the at least one second hot runner nozzle (22) in such a way that - all of the at least two valve needles (63, 64) open and close the respective gate openings (65, 66) of a mold cavity (35), and / or - at least one sprue opening (65, 66) of a mold cavity (35) is blocked by the respective valve needle (63, 64) and the at least one other valve needle (63, 64) continues to open and close the at least one other sprue opening (65, 66), and / or - all sprue openings (65, 66) of a mold cavity (35) are blocked by the respective valve needles (63, 64). [11] A method for injection molding according to claim 10, characterized by that the control device (80) provides signals to the actuating devices (41, 42) during each injection molding cycle in order to either a) to open or close all gate openings (65, 66) of a mold cavity (35) simultaneously, or b) to open and close the sprue openings (65, 66) of a mold cavity (35) at different times, or c) maintaining at least two valve needles (63, 64) in the closed position for the same mold cavity (35) to prevent melt flow into one mold cavity (35) while the melt flows into the other mold cavities (35). [12] A method for injection molding according to claim 11, characterized bythat the signals provided by the control device (80) are based on at least one of: a) the casting process data, b) the quality of each casting traced back to each mold cavity (35) and to each gate (65, 66), and c) a command from an operator which is made available to the control device (80).

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