Injection molding nozzle with sealing needles guided by guide bushings and injection molding device with such a

Abstract

Injection molding nozzle (1) for an injection molding device (100) for processing a flowable material (M), a) with a nozzle body (10) having a rear end (11) and a front end (12), wherein the rear end (11) can be arranged to a material feed (110) and the front end (12) can be arranged opposite a molding plate (120), b) with at least two shut-off needles (21, 22, 23, 24) penetrating the nozzle body (10) from the rear end (11) to the front end (12), wherein a separate guide bushing (41, 42, 43, 44) is arranged at the front end (12) of the nozzle body (10) for each shut-off needle (21, 22, 23, 24), and wherein each guide bushing (41, 42, 43, 44) has a through-opening (51, 52, 53, 54) axially aligned with the respective shut-off needle (21, 22, 23, 24) for receiving the respective shut-off needle (21, 22, 23, 24), c) with a melt guide (13) for the flowable material (M) which leads from the rear end (11) to the front end (12) of the nozzle body (10), wherein the melt guide (13) opens into the through-holes (51, 52, 53, 54) of the closure needles (21, 22, 23, 24), and d) with a heating device (30) arranged on the nozzle body (10), characterized in that each guide bushing (41, 42, 43, 44) has a sealing surface (61, 62, 63, 64) radially encompassing the through-hole (51, 52, 53, 54) which is arranged to seal against a sprue opening (121, 122, 123, 124) in the molding plate (120).

Description

[0001] The invention relates to an injection molding nozzle with closure needles according to the preamble of claim 1 and an injection molding device according to claim 15.

[0002] Injection molding nozzles are commonly used in plastics processing. They form the interface between the hot machine side and the cold mold side. On the hot machine side, a molten plastic is supplied and fed to the injection molding nozzle via a feed channel. The molten plastic is then guided through a through-channel in the injection molding nozzle to a cavity in the cold mold side. The injection molding nozzle is typically mounted on the machine side at the inlet of the through-channel. On the mold side, the nozzle's front end is positioned in or in front of the gate opening of a cavity. This exposes the injection molding nozzle to significant thermal stresses. Other important requirements for an injection molding nozzle include high pressure stability and consistent, uniform heating of the flowing molten plastic.Additionally, the front end of the injection molding nozzle must be sealed against the tool side.

[0003] The arrangement of the cavities within the mold is of increasing importance. Due to rising material costs for the molds and ever smaller injection-molded parts, various approaches have been developed to reduce the distance between the gate openings.

[0004] DE 100 84 280 T5 discloses an injection molding device with at least one heated nozzle extending forward into a nozzle receiving bore of a cooled molding plate. An insulating gap is provided in the injection area between the heated nozzle and the surrounding cooled molding plate. The injection molding nozzle has a front end, a rear end, and several evenly spaced valve needle bores extending from the rear end to the front end. An elongated valve needle is longitudinally displaceable in each valve needle bore and can be moved simultaneously between an open and a closed position by means of a drive mechanism. Furthermore, the injection molding nozzle includes a melt bore extending from a central inlet at the rear end to the front end. A valve bushing is received in a recessed seat at the front end.This nozzle also features evenly spaced valve needle bores, aligned with the valve needle bores in the nozzle body. The melt bore branches according to the number of valve needles, with each individual melt bore extending diagonally outwards in the front section and each opening into a valve needle bore of the valve bushing. The individual melt bores of the valve bushing ultimately open into needle inserts, which are secured by a common retaining bushing screwed into the front end of the nozzle body. This retaining bushing also secures the valve bushing. Finally, a nozzle seal is provided at the front end of the nozzle body, specifically at the retaining bushing. This nozzle seal encompasses all needle inserts and thus also the valve needles.However, this means the sealing needles are located in a shared hydraulically connected space, which has the disadvantage that the needle inserts within the nozzle seal lie in a common sump. This leads to negative thermal effects and incomplete gate points. Another disadvantage is the shared arrangement and fixed position of the needle inserts. This prevents individual compensation for thermal and manufacturing tolerances.

[0005] WO 2009 / 049419 A1 also concerns an injection molding nozzle with multiple valve needles. It has an externally heated nozzle body with a rear and a front end. The rear end is connected to a material feed, while the front end is located opposite a mold gate. At least two valve needles penetrate the nozzle body from the rear to the front end, with the bores in the nozzle body for the valve needles simultaneously serving as melt channels. A separate guide bushing is provided at the front end of the nozzle body for each valve needle. Each of these guide bushings has a through-hole aligned axially with its corresponding valve needle. The latter serves to receive the respective valve needle and to guide the melt. Furthermore, each guide bushing sits in a separate recess at the front end of the nozzle body.In this recess, each guide bushing is held by a screwed-in retaining bushing with a radial sealing surface. This surface corresponds to a sealing surface on the heated side of the mold. In this way, the injection molding nozzle is sealed against each individual gate opening. A disadvantage of this design is the relatively large space requirement of the retaining rings. In particular, due to the intended screw-in mounting of the retaining rings in the nozzle body, they must be sufficiently spaced apart. Furthermore, screwing in the retaining rings is time-consuming and complicated. The large number of components in the front section of the injection molding nozzle makes it expensive. Additionally, the retaining rings and their seals cannot be individually positioned relative to the cavities. This frequently leads to leaks.

[0006] WO 03 / 076163 A1 describes an injection molding nozzle with a laterally arranged actuator, used for processing a free-flowing material. This injection molding nozzle has a nozzle body in which a shut-off needle is guided. The shut-off needle is guided axially in two guide bushings. A melt guide opens in a region between the guide bushing and a nozzle opening, through which melt can be directed into the through-channel and thus to the nozzle opening. The nozzle opening is formed in a housing part of the nozzle body 20.

[0007] From DE 2 919 862 A1, an injection molding unit is known which comprises an end plate, a distributor plate, and a mold carrier plate, all designed as a fixed assembly. A guide bushing with a through-hole is arranged in the mold carrier plate, the through-hole opening leading into a nozzle opening in the mold carrier plate. A closing pin, which can be used to close the nozzle opening, is axially movable within the guide bushing.

[0008] German patent DE 19 956 215 C2 describes a hot runner needle valve nozzle with a drive for adjusting the valve needle, wherein a guide bushing is received within a nozzle body and an axial end of the guide bushing is held at a distance from the nozzle body. Within the guide bushing, a valve needle is guided axially and is movable between a closed position and an open position.

[0009] The object of the invention is therefore to eliminate these and other disadvantages of the prior art and to create an injection molding nozzle and an injection molding device that enables the injection of very closely spaced gate openings and with which high-quality injection points can be produced at the same time. A consistently reliable seal should be ensured between the injection molding nozzle and the mold plate, which can also compensate for thermally and manufacturing-related tolerances. Furthermore, it is aimed that both the injection molding nozzle and the injection molding device can be manufactured cost-effectively.

[0010] The main features of the invention are specified in claim 1 and claim 15. Embodiments are the subject of claims 2 to 14 and 16 and 17.

[0011] In an injection molding nozzle for an injection molding device for processing a flowable material, the nozzle body has a rear end and a front end, wherein the rear end can be arranged to a material feed and the front end can be arranged opposite a mold sprue plate, with at least two shut-off needles penetrating the nozzle body from the rear end to the front end, wherein a separate guide bushing is arranged at the front end of the nozzle body for each shut-off needle, and wherein each guide bushing has a through-hole axially aligned with the respective shut-off needle for receiving the respective shut-off needle, with a melt guide for the flowable material leading from the rear end to the front end of the nozzle body, wherein the melt guide opens into the through-holes of the shut-off needles.and with a heating device arranged on the nozzle body, the invention provides that each guide bushing has a sealing surface radially encompassing the through-opening, which can be arranged to seal against a sprue opening in the molding plate.

[0012] A particularly advantageous feature is the one-piece design of the guide bushing and the sealing surface. This allows for cost-effective manufacturing of the guide bushing. Furthermore, each individual through-hole is sealed against its corresponding sprue. This prevents the melt from spreading or clumping in the injection area, as occurs in the prior art due to a common sump around the sprue openings. Instead, according to the invention, an insulating gap can be formed around each guide bushing, resulting in low thermal losses and a constant plastic melt temperature within the guide bushings. Very little space is required between the individual guide bushings. Consequently, the spacing between individual sprue openings can be minimized. The separate sealing of each guide bushing enables the creation of particularly high-quality injection points.

[0013] Each shut-off needle should be axially displaceable between a closed and an open position. This allows the shut-off needles to release the individual through-holes. Depending on the requirements, the shut-off needles can either share a common drive located on the rear end of the nozzle body, or each shut-off needle can have its own drive, also located on the rear end of the nozzle body. A common drive is particularly advantageous when the cavities are of the same size or when there is a common cavity behind the gate openings. If different opening times for the shut-off needles are required, separate drives for the shut-off needles are preferable.

[0014] Preferably, the locking pins are arranged parallel to each other. Alternatively, however, a radial, i.e., star-shaped, arrangement can also be provided.

[0015] A further development of the invention provides that each guide bushing is inserted into a separate opening at the front end of the nozzle body. This prevents leaks between the individual guide bushings. In particular, the fit between the guide bushing and its associated separate opening can be machined individually. According to a more detailed embodiment, each guide bushing is inserted into its respective opening at the front end of the nozzle body. Thus, it is not necessary to screw in the guide bushing. This allows the guide bushings to be arranged particularly close together.

[0016] In particular, a design such that each guide bushing is mounted axially and telescopically in its respective opening at the front end of the nozzle body offers further advantages. These advantages primarily concern the seal between the guide bushing and the gate opening. The telescopic connection makes it possible to compensate for thermal expansion, especially that of the nozzle body, the gate plate, and, for example, a distributor. Each individual guide bushing can be moved axially relative to the gate opening. This prevents leaks between the guide bushing and the gate opening.

[0017] Preferably, the telescopic bearing is designed as a sliding seal. This prevents the escape of molten plastic between the opening at the front end of the nozzle body and the guide bushing. Such a sliding seal can be interrupted by at least one radial recess. The recess should be located on the radial outer surface of the guide bushing, as this is easier to manufacture than radial recesses on the radial inner surface of the nozzle body opening. The radial recesses improve the sealing of the sliding seal. Furthermore, they reduce friction between the guide bushing and the surrounding opening. This makes it easier to telescope the guide bushing within the opening.

[0018] To compensate for thermally induced variations in distance between the tool side and the machine side, a force storage element can be arranged between each guide bushing and the nozzle body. This element applies force to the guide bushing from the rear end of the nozzle body. Thus, each guide bushing maintains a fixed position relative to its respective gate opening. Even with uneven expansion, the seal between the guide bushing and the gate opening is always ensured. To prevent any displacement between the gate opening and the exit opening of the guide bushing, the sealing surface of each guide bushing should be positioned at the bottom of its corresponding gate opening.

[0019] Material flow through the guide bushing is particularly efficient when the through-hole of each guide bushing, between the opening of its feed channel and its sealing surface, has a channel expansion with a larger diameter than the corresponding sealing needle. Additionally, each guide bushing should have axially aligned guide ribs extending into the material exit area of ​​the through-hole to guide the corresponding sealing needle. This enables precise and close guidance of the needle, resulting in exceptionally high quality of the injection points.

[0020] As an alternative or supplement to arranging a force storage device between the nozzle body and each guide bushing, it is possible to apply force to each guide bushing in the direction of the mold plate using a hold-down device. Such a hold-down device is fixed to the mold side, i.e., to the mold plate. This ensures that the guide bushings generally have a fixed position relative to the gate opening. Depending on the available installation space, one hold-down device can be provided per guide bushing, or one hold-down device can secure several guide bushings. To simplify assembly, the guide bushings and / or the openings at the front end of the nozzle body preferably have chamfers. Alternatively, the hold-down device can also be fixed to the nozzle body and hold the guide bushings in their openings. The latter can be achieved by applying force or with clearance to allow for thermal expansion.Pre-assembly of the guide bushings on the molding plate is then not necessary.

[0021] A preferred embodiment of the invention provides that the melt guide branches in the area of ​​the guide bushings. Thus, a main melt channel exists in the nozzle body at the rear end, forming the melt guide. The main melt channel only divides in the area of ​​the guide bushings. This ensures that a homogeneous and uniformly tempered plastic mass reaches the guide bushings. Plastic of consistent quality can therefore be supplied to the gate openings. Furthermore, this results in a short residence time of the plastic mass in the hot runner system. With a large number of valve needles, several main melt channels can be provided to simplify distribution. In principle, a specific valve needle can also be assigned its own dedicated main melt channel.This allows, for example, different injection pressures to be provided at different valve needles, or even different melts to be processed, as in multi-component injection molding.

[0022] A further development of the guide bushing provides that each guide bushing has a feed channel that does not run parallel to the through-hole, but opens into the through-hole and is fluidically connected to the melt guide. Such an inclined feed channel can open radially into the through-hole of the guide bushing. This allows for the positioning of wear-prone seals and guides for the sealing pins within the guide bushing. The guide bushings are easily replaceable, and maintenance of the injection molding nozzle is particularly simple. This ensures a consistent melt channel, especially in the injection area of ​​the sprue. Furthermore, the thermal separation of the injection molding nozzle from the mold plate is optimized.

[0023] According to a further development of the invention, a sliding seal is formed in the through-opening of each guide bushing between the opening of the feed channel and the rear end of the nozzle body, in which the respective sealing needle is axially displaceable. This reduces the area of ​​the sealing needle lying in the molten plastic to an area within the guide bushing. Consequently, the sealing needle can be moved very easily. Furthermore, the seal can be easily replaced by exchanging the guide bushing.

[0024] To improve the sealing effect and reduce the friction between the locking needle and the guide bushing, each sliding seal can be interrupted in the axial direction of the associated locking needle by at least one expansion section, the diameter of which is larger than that of the sliding seal.

[0025] From a manufacturing perspective, a design in which each sliding seal has a cylindrical circumference that is coaxial with the associated sealing pin is preferable. The sealing pin should also have a cylindrical circumference.

[0026] To seal the injection molding nozzle in its closed position, a sealing surface should be formed in the through-hole of each guide bushing between the outlet of the feed channel and the side of the through-hole facing away from the rear end of the nozzle body. This sealing surface forms a seal with a corresponding sealing pin when the nozzle is closed. Both the sealing surface and the corresponding surface on the sealing pin should be conical in shape.

[0027] A particularly advantageous embodiment of the guide bushing is one in which the diameter of the through-hole of each guide bushing between the mouth of the feed channel and the sealing surface is larger than the diameter of the respective sealing needle. This allows the molten plastic supplied by the machine to reach the sealing surface in the closed position. The distance to the gate is thus minimal. Consequently, the time delay with which the molten plastic flows into the gate when the needle is moved from the closed to an open position is correspondingly short. To ensure precise guidance of the sealing needle even in the sealing surface, each guide bushing should have axially aligned guide ribs extending into the sealing surface, specifically within the through-hole.This ensures the valve needle is guided close to the gate and with pinpoint accuracy. Wear on the valve needle is therefore minimal. Axially oriented cavities exist between the guide ribs and the valve needle. These serve as return channels. When the valve needle moves from an open to a closed position, the material displaced by the valve needle can flow back through these return channels. The pressure within the cavity thus does not increase depending on the valve needle's movement. The pressure within the cavity can therefore be precisely adjusted. Furthermore, the actuators for operating the valve needle can be made smaller.

[0028] Furthermore, one embodiment of the invention provides that the feed channel of each guide bushing exits radially from the respective guide bushing relative to the through-hole. The through-holes in the nozzle body are thus not filled with plastic. The sealing needles are therefore particularly easy to move. This makes it possible to design the melt flow path as a single, unbranched melt channel from the rear end of the nozzle body to the area of ​​the guide bushings. Only in the immediate vicinity of the guide bushing can this melt channel be divided and connected to the feed channel of each guide bushing. The quality of the plastic melt is thus ensured equally in every guide bushing.

[0029] The distance between two gate openings can be minimized by arranging the through-hole and feed channel of each guide bushing in a common plane, with the thickness of the guide bushing perpendicular to this plane corresponding to the diameter of the through-hole and / or feed channel plus a minimum required wall thickness. This allows the guide bushings to be positioned particularly close together in the direction perpendicular to this plane. The minimum wall thickness is determined primarily by the wall thickness required to withstand the injection molding pressures.

[0030] To ensure a continuous flow of material from the melt guide into the feed channels of the guide bushings, the guide bushings should be arranged to prevent rotation. This ensures the supply of molten plastic into the feed channel of the guide bushing. To prevent the opening between the nozzle body and the guide bushing from narrowing during axial displacement of the guide bushing, the feed channel can be widened on the guide bushing side or on the melt guide side within the nozzle body. This widening extends primarily in the axial direction. During telescopic displacement of the guide bushing within the nozzle body, the cross-sectional area remains sufficiently large.

[0031] A minimal distance between the sprue openings can be achieved by arranging the guide bushings adjacent to each other and in contact with each other.

[0032] Preferably, each guide bushing has a radially outward-facing flange in its front region. This flange allows the guide bushing to be axially supported against the nozzle body and / or the molding plate surrounding the gate opening.

[0033] To ensure a minimal distance between the gate openings despite the flange, the flange should have opposing flattened side surfaces. These can lie in a plane parallel to the axial alignment of the corresponding sealing pin. Ideally, the guide bushings should touch at the flattened sides of this flange. The flattened sides of the flange should be tangent to the minimum required diameter of the guide bushing. Thus, the flange does not protrude beyond the minimum diameter in the direction of the adjacent guide bushing. Furthermore, two adjacent flattened sides of two guide bushings form an anti-rotation feature for the guide bushings. This is particularly important when the plastic compound enters the through-hole of the guide bushing via a lateral feed channel through the wall.

[0034] Furthermore, the flange of a guide bushing can be engaged from behind by a hold-down device attached to the molding plate. This secures the guide bushing relative to the molding plate.

[0035] For feeding molten plastic from a central machine nozzle or distributor, the melt guide at the rear end of the nozzle body can have an axially oriented feed opening. Alternatively, the melt guide at the rear end can have a feed opening oriented radially around the circumference of the nozzle body.

[0036] The invention further relates to an injection molding device with an injection molding nozzle for processing a flowable material, with a nozzle body having a rear end and a front end, wherein the rear end can be arranged to a material feed and the front end can be arranged opposite a mold sprue plate, wherein at least two shut-off needles penetrate the nozzle body from the rear end to the front end, wherein a melt guide leads from the rear end to the front end of the nozzle body, wherein a heating device is arranged on the nozzle body, wherein a separate guide bushing is arranged at the front end of the nozzle body for each shut-off needle, wherein each guide bushing has a through-opening axially aligned with the respective valve needle for receiving the respective shut-off needle, wherein the melt guide opens into the through-opening.and wherein each guide bushing has a sealing surface radially encompassing the through-hole, which can be arranged to seal against a sprue opening in the molding plate, wherein the rear end of the nozzle body is arranged at the material feed, wherein the front end of the nozzle body is arranged opposite the molding plate, and wherein each guide bushing is arranged with its sealing surface to seal against a separate sprue opening.

[0037] This provides an injection molding device that allows for the injection of closely spaced gate openings. High-quality injection points can be produced with this device. A consistently reliable seal is maintained between the injection nozzle and the mold plate. Additionally, according to the invention, thermally and manufacturing-related tolerances can be compensated for by the injection nozzle. The reduced number of components in the front section of the injection nozzle reduces the manufacturing costs of the injection molding device. To enable the injection of a large number of gate openings, either the number of guide bushings can be increased, or alternatively, the material supply can be a distributor. Using the distributor, several injection nozzles can be arranged on one side of the machine and supplied with molten plastic.

[0038] According to one embodiment of the distributor, it is formed by a distributor plate. The nozzle body of the injection molding nozzle can be fixed to this distributor. However, a radially floating mounting of the nozzle body on the distributor is preferable. The distributor allows the injection molding device to have at least one second injection molding nozzle.

[0039] In another variant of the injection molding device, each guide bushing has a radially outward-facing flange at its front end, and the guide bushing is secured to the mold plate by a retainer that engages behind the flange. Thus, the guide bushing has a substantially fixed position relative to the gate opening in the mold plate. Thermal expansion of the injection molding nozzle or device can therefore be compensated for without leaks occurring in the area of ​​the guide bushing's sealing surface. For assembly, the guide bushings can first be secured to the mold plate with the retainer, and then the nozzle body can be attached.

[0040] Further features, details and advantages of the invention will become apparent from the wording of the claims and from the following description of exemplary embodiments with reference to the drawings. The drawings show: Fig. 1. A three-dimensional view of an injection molding device with an injection molding nozzle; Fig. 2 a three-dimensional longitudinal section through the front area of ​​an injection molding nozzle; Fig. 3 a longitudinal section through the front area of ​​an injection molding nozzle; Fig. 4 a three-dimensional longitudinal section through a guide bushing and a locking pin; Fig. 5 a longitudinal section through a front area of ​​an injection molding nozzle and a molding plate; and Fig. 6 a three-dimensional longitudinal section through the rear end of an injection molding nozzle.

[0041] Fig. Figure 1 shows a three-dimensional view of an injection molding device 100 with an injection molding nozzle 1. This nozzle is used for processing a free-flowing material M. The injection molding nozzle 1 has a nozzle body 10 with a rear end 11 and a front end 12. The rear end 11 is arranged on a material feed 110, and the front end 12 can be positioned opposite a mold sprue plate. Four locking pins 21, 22, 23, 24 penetrate the nozzle body 10 from the rear end 11 to the front end 12. Concealed by the locking pins 21, 22, 23, 24 is a melt guide 13, which leads from the rear end 11 to the front end 12 of the nozzle body 10.

[0042] A heating device 30 is arranged on the nozzle body 10. In particular, this heating device surrounds the nozzle body 10 radially. The heating device 30 can be connected via an electrical heating connection 32. An electrical temperature sensor with an electrical temperature sensor connection 33 is also provided.

[0043] For each valve needle 21, 22, 23, 24, a separate guide bushing 41, 42, 43, 44 is arranged at the front end 12 of the nozzle body 10. Each of these guide bushings 41, 42, 43, 44 has a through-opening 51, 52, 53, 54 axially aligned with the respective valve needle 21, 22, 23, 24 for receiving the respective valve needle 21, 22, 23, 24. The melt guide 13, concealed by the valve needles 21, 22, 23, 24, opens into the through-openings of the guide bushings 41, 42, 43, 44.

[0044] At its rear end 11, the nozzle body 10 with a nozzle head 31 is fixed to a distributor plate 112 of a distributor 111. Within the distributor plate 112, a distributor channel 114 leads to a feed opening 19 of the melt channel 18 of the injection molding nozzle 1. This distributor channel 114 is flow-connected to a central machine nozzle via a connecting nozzle 113.

[0045] Furthermore, the sealing needles 21, 22, 23, 24 protrude through the distributor plate 112 at the rear end 11 of the injection molding nozzle 1. On the side of the distributor plate 112 opposite the nozzle head 31, the sealing needles 21, 22, 23, 24 are connected to a drive 140. This drive 140 is located linearly behind the sealing needles 21, 22, 23, 24. It is a common drive 140 for the sealing needles 21, 22, 23, 24. The sealing needles 21, 22, 23, 24 are arranged parallel to each other and are axially displaceable between a closed position and an open position.

[0046] In Fig. Figure 2 shows a three-dimensional longitudinal section through the front end 12 of an injection molding nozzle 1. The injection molding nozzle 1 has a nozzle body 10 that extends from a rear end 11 to the front end 12. The front end 12 can be positioned opposite a mold sprue plate. As can also be seen, two sealing pins 21, 22 penetrate the nozzle body 10 from the rear end 11 to the front end 12. A melt guide 13 also leads from the rear end 11 to the front end 12.

[0047] A heating device 30 is arranged on the nozzle body 10. The latter surrounds the nozzle body 10 radially. In particular, the heating device 30 is a thin-film heater. At the front end 12 of the nozzle body 10, a separate guide bushing 41, 42 is arranged for each valve needle 21, 22. Each guide bushing 41, 42 has a through-opening 51, 52 aligned axially with the respective valve needle 21, 22. The melt guide 13 opens into the through-opening 51, 52 of the guide bushings 41, 42. Each of the guide bushings 41, 42 has a sealing surface 61, 62 that radially encompasses the through-opening 51, 52. This sealing surface can be arranged to seal against a sprue opening in a molding plate.

[0048] The sealing needles 21, 22 are arranged parallel to each other and are each axially displaceable between a closed and an open position. The bearing is achieved at the front end 12, in particular by the guide bushings 41, 42, each of which is inserted into a separate opening 14, 15 at the front end 12 of the nozzle body 10. Specifically, each guide bushing 41, 42 is inserted into the respective opening 14, 15 at the front end 12 of the nozzle body 10. Furthermore, each guide bushing 41, 42 is axially telescopically mounted in its respective opening 14, 15. This telescopic mounting is designed as a sliding seal. Due to the telescopic nature of the guide bushings 41, 42, they generally maintain a fixed position relative to the respective gate opening.

[0049] The melt guide 13 comprises a melt channel 18. In the region of the guide bushings 41, 42, the melt guide 13 branches. Each guide bushing 41, 42 has a feed channel 71, 72 that does not run parallel to the through-opening 51, 52. This feed channel opens into the through-opening 51, 52 of the guide bushing 41, 42 and is fluidically connected to the melt guide 13. The feed channel 71, 72 of each guide bushing 41, 42 thus exits radially from the respective guide bushing 41, 42 relative to the through-opening 51, 52.

[0050] The through-hole 51, 52 and the feed channel 71, 72 of each guide bushing lie in a common plane. The thickness of the guide bushing 41, 42 perpendicular to the plane corresponds to the diameter of the through-hole 51, 52 plus a minimum required wall thickness.

[0051] Furthermore, each guide bushing 41, 42 has a radially outwardly projecting flange 25. This flange 25 has one flattened side. This flattened side lies in a plane parallel to the axial orientation of the associated locking pin 21, 22. The guide bushings 41, 42 contact each other at the flattened sides of the flange 25. This prevents the guide bushings 41, 42 from rotating.

[0052] In Fig. Figure 3 shows a longitudinal section through the front end 12 of an injection molding nozzle 1. The injection molding nozzle 1 has a nozzle body 10 that extends from a rear end 11 to a front end 12. The rear end 11 can be positioned on a material feed, and the front end 12 can be positioned opposite a mold sprue plate. Four locking pins 21, 22, 23, 24 penetrate the nozzle body 10 from the rear end 11 to the front end 12. Through-holes 26, 27, 28, 29 are provided in the nozzle body 10 for this purpose. A melt guide from the rear end 11 to the front end 12 of the nozzle body 10 is not visible in this view. Furthermore, the nozzle body 10 is radially surrounded by a heating device 30.

[0053] At the front end 12 of the nozzle body 10, a separate guide bushing 41, 42, 43, 44 is arranged for each valve needle 21, 22, 23, 24. Each of these guide bushings 41, 42, 43, 44 has a through-hole 51, 52, 53, 54, axially aligned with the respective valve needle 21, 22, 23, 24, for receiving the respective valve needle 21, 22, 23, 24. The non-visible melt guide opens into these through-holes 51, 52, 53, 54. Furthermore, each guide bushing 41, 42, 43, 44 has a sealing surface 61, 62, 63, 64 radially encompassing the through-hole 51, 52, 53, 54. This sealing surface can be arranged to seal against a sprue opening in the molding plate. Both the locking pins 21, 22, 23, 24 and the through bores 26, 27, 28, 29 and the through opening 51, 52, 53, 54 of the guide bushings 41, 42, 43, 44 are aligned parallel to each other. The locking pins 21, 22, 23, 24 are axially displaceable between a closed position and the open position S2 shown.In particular, the bearings are provided by means of guide bushings 41, 42, 43, 44, each of which is inserted into a separate opening 14, 15, 16, 17 at the front end 12 of the nozzle body 10. Insertion is achieved primarily by pushing the bushings in. This allows each guide bushing 41, 42, 43, 44 to be axially and telescopically mounted in its respective opening 14, 15, 16, 17 at the front end 12 of the nozzle body 10. The telescopic bearings are each designed as a sliding seal. The telescopic connection allows each guide bushing 41, 42, 43, 44 to assume a generally fixed position relative to the respective gate opening.

[0054] Each guide bushing 41, 42, 43, 44 has a feed channel 71, 72, 73, 74 that does not run parallel to the through-opening 51, 52, 53, 54. This feed channel opens into the respective through-opening 51, 52, 53, 54 and is fluidically connected to the melt guide. In the through-opening 51, 52, 53, 54 of each guide bushing 41, 42, 43, 44, a sliding seal 91, 92, 93, 94 is formed between the opening 81, 82, 83, 84 of the feed channel 71, 72, 73, 74 and the rear end 11 of the nozzle body 10, in which the respective sealing needle 21, 22, 23, 24 is axially displaceably mounted. The respective sliding seals 91, 92, 93, 94 are interrupted in the axial direction of the associated sealing needle 21, 22, 23, 24 by expansion sections 85, 86, 87, 88. The diameter of these expansion sections is each larger than that of the sliding seal 91, 92, 93, 94. Furthermore, each sliding seal 91, 92, 93, 94 has a cylindrical circumference that is aligned coaxially with the associated sealing needle 21, 22, 23, 24.

[0055] Within the through-opening 51, 52, 53, 54 of each guide bushing 41, 42, 43, 44, a sealing surface 95, 96, 97, 98 is located between the opening 81, 82, 83, 84 of the feed channel 71, 72, 73, 74 and the side of the through-opening 51, 52, 53, 54 facing away from the rear end 12 of the nozzle body 10. In a closed position, this sealing surface forms a seal with the associated sealing needle 21, 22, 23, 24. Each sealing surface 95, 96, 97, 98 encompasses the sealing needle 21, 22, 23, 24 in the closed position. Specifically, the sealing surfaces 95, 96, 97, 98 are conically shaped for this purpose. That is, they are conically widening towards the rear end 11 of the nozzle body 10.

[0056] As can be further seen, the diameter of the through-hole 51,52,53,54 of each guide bushing 41,42,43,44 between the mouth 75,76,77,78 of the feed channel 71,72,73,74 and the sealing surface 95,96,97,98 is larger than the diameter of the respective sealing needle 21,22,23,24.

[0057] A particularly close arrangement of the guide bushings 41, 42, 43, 44 is achieved by having the through-hole 51, 52, 53, 54 and the feed channel 71, 72, 73, 74 of each guide bushing 41, 42, 43, 44 lie in a common plane. The thickness B of the guide bushing 41, 42, 43, 44 perpendicular to this plane corresponds to the diameter of the through-hole 51, 52, 53, 54 plus a minimum necessary wall thickness, plus half the distance between the adjacent openings 14, 15, 16, 17 at the front end 12 of the nozzle body 10.

[0058] Fig. Figure 4 shows a three-dimensional representation of a longitudinal section through a guide bushing 41, 42, 43, 44 and a closing pin 21, 22, 23, 24, which is in an open position S2. The representation can apply to several guide bushings 41, 42, 43, 44 of an injection molding nozzle, which is why it has been labelled with reference numerals for several guide bushings 41, 42, 43, 44.

[0059] The intended position within a nozzle body is indicated, with the shut-off needle 21, 22, 23, 24 extending from a rear end 11 to a front end 12. The guide bushing 41, 42, 43, 44 has a through-opening 51, 52, 53, 54 axially aligned with the associated shut-off needle 21, 22, 23, 24 for receiving it. Furthermore, the guide bushing 41, 42, 43, 44 has a sealing surface 61, 62, 63, 64 radially encompassing the through-opening 51, 52, 53, 54. This sealing surface is specifically located at the front end 12 of the guide bushing 41, 42, 43, 44. Thus, the guide bushing 41, 42, 43, 44 can be arranged to seal against a sprue opening in a molding plate.

[0060] Towards its rear end 11, the guide bushing 41, 42, 43, 44 has a cylindrical outer circumference. This allows it to be inserted into separate openings at the front end of a nozzle body, particularly by insertion. The design of the section of the guide bushing 41, 42, 43, 44 and the receiving opening at the front end of a nozzle body provides telescopic support for the guide bushing 41, 42, 43, 44. To facilitate easy installation, the guide bushing 41, 42, 43, 44 features an insertion chamfer at its rear end 11. The telescopic support also forms a sliding seal. This sliding seal 91, 92, 93, 94 is interrupted in the axial direction of the locking pin 21, 22, 23, 24 by three expansion sections 85, 86, 87, 88. The diameter of these expansion sections is larger than that of the sliding seal 91, 92, 93, 94.This improves the seal and reduces the friction between the locking needle 21,22,23,24 and the guide bushing 41,42,43,44 when moving from an open position S2 to a closed position.

[0061] In the region of the cylindrical outer circumference at the rear end 11, the guide bushing 41, 42, 43, 44 has a feed channel 71, 72, 73, 74 that does not run parallel to the through-opening 51, 52, 53, 54. This feed channel opens into the through-opening 51, 52, 53, 54 and can be flow-connected to a melt guide of a nozzle body. The opening 81, 82, 83, 84 of the feed channel 71, 72, 73, 74 opens into the through-opening 51, 52, 53, 54, specifically between the sliding seal 91, 92, 93, 94 and the front end 12 of the guide bushing 41, 42, 43, 44. The inlet opening of the feed channel 71, 72, 73, 74 is located in the cylindrical shell at the rear end 11 of the guide bushing 41, 42, 43, 44. In particular, it is radially oriented.

[0062] In the through-opening 51, 52, 53, 54 of the guide bushing 41, 42, 43, 44, a sealing surface 95, 96, 97, 98 is formed between the opening 81, 82, 83, 84 of the feed channel 71, 72, 73, 74 and the side of the through-opening 51, 52, 53, 54 facing away from the rear end 12 of the nozzle body. In a closed position, this sealing surface forms a seal with the associated sealing needle 21, 22, 23, 24. For this purpose, the sealing needle 21, 22, 23, 24 has a conical tip 75, 76, 77, 78 at its front end 12. The sealing surface 95, 96, 97, 98 is also conical. The sealing surface 95,96,97,98 thus encompasses the received sealing needle 21,22,23,24 in its closed position.

[0063] The diameter of the through-hole 51, 52, 53, 54 of the guide bushing 41, 42, 43, 44 is larger between the opening 75, 76, 77, 78 of the feed channel 71, 72, 73, 74 and the sealing surface 95, 96, 97, 98 than the diameter of the sealing needle 21, 22, 23, 24. This channel widening 65, 66, 67, 68 allows the flow of molten plastic to the sealing surface 95, 96, 97, 98 within the guide bushing 41, 42, 43, 44, even when the sealing needle 21, 22, 23, 24 is closed.

[0064] To precisely guide the tip of the closure needle 21, 22, 23, 24, even in the area of ​​the closure sealing surface 95, 96, 97, 98, axially aligned guide webs 55, 56, 57, 58 are provided in the channel widening 65, 66, 67, 68 up to the area of ​​the closure sealing surface 95, 96, 97, 98 to guide the closure needle 21, 22, 23, 24.

[0065] Furthermore, a sealing surface 61,62,63,64 is provided for sealing against a molded sprue plate at the front end 12 of the guide bushing 41,42,43,44.

[0066] At the front end 12 of the guide bushing 41, 42, 43, 44, a radially outwardly projecting flange 25 is also attached. This can be axially supported on a nozzle body or on a sprue opening.

[0067] The sealing surface 61, 62, 63, 64 for sealing the guide bushing 41, 42, 43, 44 against a molded sprue plate is located at the front end of the guide bushing 41, 42, 43, 44. The distance between this sealing surface 61, 62, 63, 64 and the closing sealing surface 95, 96, 97, 98 within the through-opening 51, 52, 53, 54 is reduced to a minimum. This minimum is based on the minimum wall thickness required to ensure the stability of the guide bushing 41, 42, 43, 44. A tapered outlet opening 59 of the through-opening 51, 52, 53, 54 is located at the center of the closing sealing surface 95, 96, 97, 98 and the end-face sealing surface 61, 62, 63, 64.

[0068] Fig. Figure 5 shows a longitudinal section through an injection molding nozzle 1, which is positioned with its front end 12 opposite a mold plate 120. The injection molding nozzle 1 has a nozzle body 10, which extends from a rear end 11 to a front end 12. The rear end 11 can be positioned on a material feed. A sealing pin 21, 22, 23, 24 penetrates the nozzle body 10 from the rear end 11 to the front end 12. A heating device 30 is located on the circumference of the nozzle body 10.

[0069] A guide bushing 41, 42, 43, 44 is arranged at the front end 12 of the nozzle body 10 for the shut-off needle 21, 22, 23, 24. The guide bushing 41, 42, 43, 44 has a through-opening 51, 52, 53, 54 aligned axially with the shut-off needle 21, 22, 23, 24. A melt guide 13 opens into this through-opening 51, 52, 53, 54 and extends from the rear end 11 towards the front end 12 through the nozzle body 10. The guide bushing 41, 42, 43, 44 has a sealing surface 61, 62, 63, 64 that radially encompasses the through-opening 51, 52, 53, 54. This sealing surface is arranged to seal against a gate opening 121, 122, 123, 124 in the molding plate 120.

[0070] The guide bushing 41, 42, 43, 44 is inserted into an opening 14, 15, 16, 17 at the front end 12 of the nozzle body 10. This opening 14, 15, 16, 17 has a cylindrical circumference and extends coaxially to the sealing needle 21, 22, 23, 24. The guide bushing 41, 42, 43, 44 also has a cylindrical circumference in the region of the opening 14, 15, 16, 17. This allows the guide bushing 41, 42, 43, 44 to be inserted into the opening 14, 15, 16, 17. In particular, the guide bushing 41, 42, 43, 44 is mounted axially and telescopically in the opening 14, 15, 16, 17 at the front end 12 of the nozzle body 10. This telescopic mounting forms a sliding seal. This enables the guide bushing 41, 42, 43, 44 to be fixed to the molding plate 120 by means of a hold-down device 45, 46, 47, 48. The latter is screwed to the molding plate 120 and engages behind a flange 25 of the guide bushing 41, 42, 43, 44.The guide bushing 41, 42, 43, 44 is thus always pressed against the molding plate 120 with its sealing surface 61, 62, 63, 64. Thermal expansion changes of the nozzle body 10 can thus be compensated for.

[0071] Furthermore, the guide bushing 41, 42, 43, 44 has a feed channel 71, 72, 73, 74 that does not run parallel to the through-opening 51, 52, 53, 54. This feed channel opens into the through-opening 51, 52, 53, 54 and is fluidically connected to the melt guide 13. The melt guide 13, in turn, is designed as a melt channel 18, which only branches immediately in the area of ​​the guide bushings 14, 15, 16, 17.

[0072] In the through-opening 51, 52, 53, 54 of the guide bushing 41, 42, 43, 44, a sliding seal 91, 92, 93, 94 is formed between the opening 81, 82, 83, 84 of the feed channel 71, 72, 73, 74 and the rear end 11 of the nozzle body 10. The shut-off needle 21, 22, 23, 24 is axially displaceably mounted in this seal. The sliding seal 91, 92, 93, 94 is interrupted in the axial direction of the shut-off needle 21, 22, 23, 24 by three expansion sections 85, 86, 87, 88. The diameter of each of these expansion sections is larger than that of the sliding seal 91, 92, 93, 94. Furthermore, the sliding seal 91,92,93,94 has a cylindrical circumference that is aligned coaxially with the locking needle 21,22,23,24.

[0073] In the through-opening 51, 52, 53, 54 of the guide bushing 41, 42, 43, 44, a sealing surface 95, 96, 97, 98 is located between the opening 81, 82, 83, 84 of the feed channel 71, 72, 73, 74 and the side of the through-opening 51, 52, 53, 54 facing away from the rear end 12 of the nozzle body 10. In a closed position of the associated sealing needle 21, 22, 23, 24, this needle, together with the sealing surface 95, 96, 97, 98, forms a seal. The sealing surface 95, 96, 97, 98 is conically shaped. That is, the sealing surface 95, 96, 97, 98 widens conically towards the rear end 11 of the nozzle body 10. The corresponding area of ​​the locking needle 21, 22, 23, 24 is designed as a conical tip 75, 76, 77, 78. In a closed position of the locking needle 21, 22, 23, 24, the latter is radially encompassed by the sealing surface 95, 96, 97, 98.

[0074] The through-opening 51, 52, 53, 54 of the guide bushing 41, 42, 43, 44 has a larger diameter between the opening 75, 76, 77, 78 of the feed channel 71, 72, 73, 74 and the sealing surface 95, 96, 97, 98 than the sealing needle 21, 22, 23, 24. Guide ribs 55, 56, 57, 58, projecting axially into the area of ​​the sealing surface 95, 96, 97, 98, are arranged in this channel widening 65, 66, 67, 68. These ribs serve to guide the sealing needle 21, 22, 23, 24.

[0075] Fig.Figure 6 shows a three-dimensional longitudinal section through the rear end 11 of an injection molding nozzle 1. At this end, a nozzle head 31 of a nozzle body 10 is located, for attaching the injection molding nozzle 1 to a central machine nozzle or a distributor. In a region further towards the front end 12 of the nozzle body 10, it is surrounded by a radial heating device 30. This heating device is supplied with electrical energy via an electrical heating connection 32 leading radially into the nozzle head 31. Parallel to this heating connection 32, an additional electrical thermocouple connection 33 leads into the nozzle head 31.

[0076] Through the nozzle body 10, sealing pins 21, 22, 23, 24 extend from the rear end 11 towards the front end 12. It is clearly visible that the through-bores 26, 27, 28, 29 in the nozzle body 10, through which the sealing pins 21, 22, 23, 24 pass, have a larger diameter than the sealing pins 21, 22, 23, 24. Only at the rear end 11 of the nozzle body 10, particularly in the area of ​​the nozzle head 31, are bearing bushings 35, 36, 37, 38 inserted into the through-bores 26, 27, 28, 29. The through bores 26, 27, 28, 29 have a slightly larger diameter at the rear end 11 than towards the front end 12. The bearing bushings 35, 36, 37, 38 have a bearing surface interrupted by several annular grooves. This reduces friction between the locking pins 21, 22, 23, 24 and the bearing bushings 35, 36, 37, 38. Furthermore, the bearing bushings 35, 36, 37, 38 form a seal, the effectiveness of which is enhanced by the radial grooves.While a seal should not normally be necessary in this area, it provides effective protection in the event of another seal failure. This reduces the risk of the injection mold 100 being flooded with solidifying molten plastic. The shut-off needles 21, 22, 23, 24 are thus supported at the rear end 11 of the nozzle body 10 by the bearing bushings 35, 36, 37, 38 and at the front end 12 by the guide bushings 41, 42, 43, 44 (which are not shown here). All bearing points are easily replaceable. Furthermore, the friction of each shut-off needle 21, 22, 23, 24 is very low when moving from an open position S2 to a closed position.

[0077] The invention is not limited to one of the embodiments described above, but can be modified in a variety of ways. Among other things, the number of guide sleeves and valve needles can be determined as required, several injection molding nozzles can be arranged on a common manifold, and the invention is not limited to an axial alignment of the valve needles and the associated bearings. Rather, a radial arrangement of the valve needles can also be provided, in which case an anti-rotation device should be formed between a guide element of the nozzle body and one of the guide sleeves.

[0078] All features and advantages arising from the claims, the description and the drawing, including design details, spatial arrangements and process steps, can be essential to the invention both individually and in various combinations. Reference symbol list 1 injection molding nozzle 10 nozzle bodies 11 rear end 12 front end 13 Melt guidance 14 first opening 15 second opening 16 third opening 17 fourth opening 18 Melt channel 19 Feed opening 21 first locking pin 22 second locking pin 23 third locking pin 24 fourth locking pin 25 flange 251 flattened side 26 first through hole 27 second through hole 28 third through hole 29 fourth through bore 30 Heating device 31 nozzle head 32 electrical heating connection 33 electrical thermocouple connection 35 first bearing bushing 36 second bearing bushing 37 third bearing bushing 38 fourth bearing bushing 41 first guide bushing 42 second guide bushing 43 third guide bushing 44 fourth guide bushing 45 first hold-down device 46 second hold-down device 47 third hold-down 48 fourth hold-down 51 first passageway 52 second passageway 53 third passageway 54 fourth passageway 55 first guide bridges 56 second guide bridges 57 third guide bridges 58 fourth guideways 61 first sealing surface 62 second sealing surface 63 third sealing surface 64 fourth sealing surface 65 first canal widening 66 second canal widening 67 third canal widening 68 fourth canal widening 71 first feed channel 72 second feed channel 73 third feed channel 74 fourth feed channel 75 first cone tip 76 second cone tip 77 third cone point 78 fourth cone point 81 first mouth 82 second mouth 83 third mouth 84 fourth mouth 85 first extension section 86 second extension section 87 third extension section 88 fourth extension section 91 first sliding seal 92 second sliding seal 93 third sliding seal 94 fourth sliding seal 95 first sealing surface 96 second sealing surface 97 third sealing surface 98 fourth sealing surface 100 injection molding devices 110 Material feed . 111 distributors 112 Distribution plate 113 Connection nozzle 114 Distribution channel 120 Molding plate 121 first sprue 122 second sprue 123 third sprue 124 fourth sprue 140 drive B Thickness of the guide bushing M flowable material S2 disclosure

Claims

[1] Injection molding nozzle (1) for an injection molding device (100) for processing a flowable material (M), a) with a nozzle body (10) having a rear end (11) and a front end (12), wherein the rear end (11) can be arranged to a material feed (110) and the front end (12) can be arranged opposite a molding plate (120), b) with at least two shut-off needles (21, 22, 23, 24) penetrating the nozzle body (10) from the rear end (11) to the front end (12), wherein a separate guide bushing (41, 42, 43, 44) is arranged at the front end (12) of the nozzle body (10) for each shut-off needle (21, 22, 23, 24), and wherein each guide bushing (41, 42, 43, 44) has a through-opening (51, 52, 53, 54) axially aligned with the respective shut-off needle (21, 22, 23, 24) for receiving the respective shut-off needle (21, 22, 23, 24), c) with a melt guide (13) for the flowable material (M) which leads from the rear end (11) to the front end (12) of the nozzle body (10), wherein the melt guide (13) opens into the through-holes (51, 52, 53, 54) of the closure needles (21, 22, 23, 24), and d) with a heating device (30) arranged on the nozzle body (10), characterized by , that each guide bushing (41, 42, 43, 44) has a sealing surface (61, 62, 63, 64) radially encompassing the through-hole (51, 52, 53, 54) which is arranged to seal against a sprue opening (121, 122, 123, 124) in the molding sprue plate (120). [2] Injection molding nozzle (1) according to claim 1, characterized by , that each guide bushing (41, 42, 43, 44) is inserted into a separate opening (14, 15, 16, 17) at the front end (12) of the nozzle body (10). [3] Injection molding nozzle (1) according to claim 2, characterized by, that each guide bushing (41, 42, 43, 44) is inserted into the respective opening (14, 15, 16, 17) at the front end (12) of the nozzle body (10). [4] Injection molding nozzle (1) according to one of claims 2 or 3, characterized by , that each guide bushing (41, 42, 43, 44) is axially telescopically mounted in the respective opening (14, 15, 16, 17) at the front end (12) of the nozzle body (10). [5] Injection molding nozzle (1) according to one of the preceding claims, characterized by , that the melt guide (13) branches in the area of ​​the guide bushings (41, 42, 43, 44). [6] Injection molding nozzle (1) according to one of the preceding claims, characterized by , that each guide bushing (41, 42, 43, 44) has a feed channel (71, 72, 73, 74) which does not run parallel to the through-hole (51, 52, 53, 54) and which opens into the through-hole (51, 52, 53, 54) and is flow-connected to the melt guide (13). [7] Injection molding nozzle (1) according to claim 6, characterized by, that in the through-opening (51, 52, 53, 54) of each guide bushing (41, 42, 43, 44) between the opening (81, 82, 83, 84) of the feed channel (71, 72, 73, 74) and the rear end (11) of the nozzle body (10) a sliding seal (91, 92, 93, 94) is formed in which the respective closing needle (21, 22, 23, 24) is axially displaceable. [8] Injection molding nozzle (1) according to claim 7, characterized by , that each sliding seal (91, 92, 93, 94) is interrupted in the axial direction of the associated closure needle (21, 22, 23, 24) by at least one expansion section (85, 86, 87, 88) whose diameter is each larger than that of the sliding seal (91, 92, 93, 94). [9] Injection molding nozzle (1) according to any one of claims 6 to 8, characterized by, that in the through-opening (51, 52, 53, 54) of each guide bushing (41, 42, 43, 44) between the opening (81, 82, 83, 84) of the feed channel (71, 72, 73, 74) and the side of the through-opening (51, 52, 53, 54) facing away from the rear end (12) of the nozzle body (10) a sealing surface (95, 96, 97, 98) is formed which, in a closed position of the associated sealing needle (21, 22, 23, 24) forms a seal with it. [10] Injection molding nozzle (1) according to claim 9, characterized by , that the diameter of the through-hole (51, 52, 53, 54) of each guide bushing (41, 42, 43, 44) between the mouth (75, 76, 77, 78) of the feed channel (71, 72, 73, 74) and the sealing surface (95, 96, 97, 98) is larger than the diameter of the respective sealing needle (21, 22, 23, 24). [11] Injection molding nozzle (1) according to any one of claims 6 to 10, characterized by, that the feed channel (71, 72, 73, 74) of each guide bushing (41, 42, 43, 44) exits radially from the respective guide bushing (41, 42, 43, 44) relative to the through-hole (51, 52, 53, 54). [12] Injection molding nozzle (1) according to any one of claims 6 to 11, characterized by , that the through-hole (51, 52, 53, 54) and the feed channel (71, 72, 73, 74) of each guide bushing (41, 42, 43, 44) lie in a common plane, wherein the thickness (B) of the guide bushing (41, 42, 43, 44) perpendicular to the plane corresponds to the diameter of the through-hole (51, 52, 53, 54) and / or the feed channel (71, 72, 73, 74) plus a minimum necessary wall thickness. [13] Injection molding nozzle (1) according to one of the preceding claims, characterized by , that the guide bushings (41, 42, 43, 44) are arranged in the nozzle body (10) in a rotationally secured manner. [14] Injection molding nozzle (1) according to any one of the preceding claims, characterized by, that each guide bushing (41, 42, 43, 44) has a radially outwardly extending flange (25) in its front area, which has opposing flattened side surfaces (251), wherein two guide bushings (41, 42, 43, 44) are in contact with each other with their flattened side surfaces (251). [15] Injection molding device (100) with an injection molding nozzle (1) according to one or more of the preceding claims, wherein the rear end (11) of the nozzle body (10) is arranged at the material feed (110), wherein the front end (12) of the nozzle body (10) is arranged opposite the molding plate (120), and wherein each guide bushing (41, 42, 43, 44) with its sealing surface (61, 62, 63, 64) is each arranged sealingly in a separate gate opening (121, 122, 123, 124). [16] Injection molding device (100) according to claim 15, characterized by , that the material supply (110) includes a distributor (111). [17] Injection molding device (100) according to one of claims 15 or 16, characterized by , that each guide bushing (41, 42, 43, 44) has a radially outwardly extending flange (25) in its front area, and the guide bushing (41, 42, 43, 44) is fixed to the molding plate (120) by a retainer (45, 46, 47, 48) which engages behind the flange (25).

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