A nozzle structure

Abstract

The utility model relates to hot runner system technical field especially relates to a kind of nozzle structure, it includes nozzle head, nozzle cylinder, valve needle, positioning member and drive assembly, nozzle cylinder is equipped with the material injection space extending along axial direction, nozzle head is equipped with the discharge port of the communication material injection space, valve needle is movably arranged in material injection space along axial direction, one end of valve needle is used to cooperate with discharge port to open or close discharge port, drive assembly is used to drive valve needle moves along axial direction, positioning member is arranged in material injection space and is located between nozzle head and drive assembly, positioning member is equipped with the first passage for valve needle to pass through and the second passage for melt to pass, first passage is coaxially arranged with discharge port, first passage and valve needle gap cooperation.By the coaxial arrangement of first passage on positioning member and discharge port, and make valve needle and first passage gap cooperation, valve needle is guided and corrected in moving process by first passage, ensure that valve needle can enter and exit discharge port with correct angle and position.

Description

Technical Field

[0001] This utility model relates to the field of hot runner system technology, and in particular to a nozzle structure. Background Technology

[0002] Valve-type nozzles in hot runner systems are widely used in precision injection molds. Their working principle typically involves a cylinder or hydraulic cylinder driving a valve needle to reciprocate axially within the nozzle channel, thereby opening or closing the mold's outlet.

[0003] During the injection molding process, due to differences in thermal expansion between the nozzle and the mold, processing errors, or slight displacement during high-pressure injection, the valve needle head is prone to deviation. This deviation can cause the valve needle to fail to accurately align with the center of the ejector when closing at high speed, and it is easy to collide with the edge of the ejector at the bottom of the mold cavity. Long-term collisions will not only damage the ejector, causing flash or appearance defects in the plastic parts, but also cause wear or even breakage of the valve needle head, seriously affecting the service life of the equipment and production stability. Utility Model Content

[0004] The technical problem to be solved by this utility model is to solve at least one of the technical problems mentioned above.

[0005] The solution to the technical problem of this utility model is: a nozzle structure, which includes a nozzle head, a nozzle cylinder, a valve needle, a positioning component, and a drive assembly. The nozzle cylinder has an axially extending injection space. The nozzle head is disposed at one end of the nozzle cylinder and has a discharge port communicating with the injection space. The valve needle is axially movable within the injection space, and one end of the valve needle is used to cooperate with the discharge port to open or close the discharge port. The drive assembly is disposed at the end of the nozzle cylinder away from the nozzle head, and the output end of the drive assembly is fixedly connected to the end of the valve needle away from the discharge port, for driving the valve needle to move axially. The positioning component is disposed within the injection space and located between the nozzle head and the drive assembly. The positioning component divides the injection space into a first space near the drive assembly and a second space near the nozzle head. The positioning component has a first channel for the valve needle to pass through and a second channel for the molten material to pass through. The first channel is coaxially arranged with the discharge port and has a clearance fit with the valve needle.

[0006] As a further improvement to the above technical solution, the first channel is a first through hole, which is provided to extend through the axial direction of the positioning member, and the first through hole connects the first space and the second space.

[0007] As a further improvement to the above technical solution, the second channel includes a plurality of second through holes, which are evenly arranged around the first through hole, and the second through holes connect the first space and the second space.

[0008] As a further improvement to the above technical solution, the positioning member is further provided with a first recess, which is disposed on the end face of the positioning member facing the first space, and the entrance of the second channel is connected to the first recess.

[0009] As a further improvement to the above technical solution, the first recess is disposed in the middle of the end face of the positioning member facing the first space, and the width of the first recess gradually increases from the direction close to the nozzle head to the direction away from the nozzle head.

[0010] As a further improvement to the above technical solution, the positioning member is also provided with a second recess, which is disposed on the end face of the positioning member facing the second space, and the outlet of the second channel is connected to the second recess.

[0011] As a further improvement to the above technical solution, the second recess is disposed in the middle of the end face of the positioning member facing the second space, and the width of the second recess gradually increases from the direction away from the nozzle head to the direction closer to the nozzle head.

[0012] As a further improvement to the above technical solution, the positioning component is integrally formed with the nozzle cylinder.

[0013] The beneficial effects of this utility model are as follows: the nozzle head delivers molten material to the mold outlet; the interior of the nozzle cylinder is used to contain the molten material; the drive assembly provides axial movement power for the valve needle, enabling the valve needle to open or close the outlet through axial movement, thereby controlling whether the molten material flows out; the first channel on the positioning component provides radial support and guidance during the movement stroke of the valve needle, ensuring the alignment of the valve needle with the outlet; the second channel ensures that the molten material can smoothly flow from the first space into the second space and finally be ejected from the outlet. By setting the first channel on the positioning component coaxially with the outlet and making the valve needle and the first channel in clearance fit, the valve needle is guided and corrected by the first channel of the positioning component during movement, ensuring that the valve needle always enters and exits the outlet at the correct angle and position, fundamentally avoiding collision between the valve needle and the edge of the outlet; eliminating lateral collision between the valve needle and the nozzle head, reducing wear on the valve needle head and nozzle head, extending the service life of the valve needle, nozzle head and mold, and reducing maintenance costs and parts replacement frequency. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a nozzle structure in the prior art; Figure 2 This is a schematic diagram of one embodiment of the present invention; Figure 3 This is a structural schematic diagram of a positioning component according to one embodiment of the present invention.

[0015] Reference numerals in the attached drawings: 100-nozzle head, 110-outlet, 200-nozzle cylinder, 300-valve needle, 400-positioning element, 410-first channel, 420-second channel, 430-first recess, 440-second recess, 500-drive assembly. Detailed Implementation

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments have been briefly explained above. Obviously, the described drawings are only a part of the embodiments of this utility model, not all of them. Those skilled in the art can obtain other design schemes and drawings based on these drawings without creative effort.

[0017] The following will clearly and completely describe the concept, specific structure, and technical effects of this utility model in conjunction with embodiments and accompanying drawings, so as to fully understand the purpose, features, and effects of this utility model. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are all within the scope of protection of this utility model. Furthermore, all connections / linkages mentioned herein do not simply refer to direct contact between components, but rather to the ability to form a better connection structure by adding or reducing connecting accessories according to specific implementation conditions. The various technical features in this utility model can be combined interactively without contradicting each other.

[0018] Valve-type nozzles in hot runner systems are widely used in precision injection molds. For example... Figure 1 As shown, its working principle is usually to drive the valve needle to make axial reciprocating motion in the nozzle channel by a cylinder or oil cylinder to open or close the mold outlet.

[0019] During the injection molding process, due to differences in thermal expansion between the nozzle and the mold, processing errors, or slight displacement during high-pressure injection, the valve needle head is prone to deviation. This deviation can cause the valve needle to fail to accurately align with the center of the ejector when closing at high speed, and it is easy to collide with the edge of the ejector at the bottom of the mold cavity. Long-term collisions will not only damage the ejector, causing flash or appearance defects in the plastic parts, but also cause wear or even breakage of the valve needle head, seriously affecting the service life of the equipment and production stability.

[0020] Therefore, this utility model proposes a nozzle structure, referring to... Figure 2 and Figure 3 It includes a nozzle head 100, a nozzle cylinder 200, a valve needle 300, a positioning element 400, and a drive assembly 500. The nozzle cylinder 200 has an axially extending injection space. The nozzle head 100 is located at one end of the nozzle cylinder 200 and has an outlet 110 communicating with the injection space. The valve needle 300 is axially movable within the injection space, and one end of the valve needle 300 cooperates with the outlet 110 to open or close the outlet 110. The drive assembly 500 is located at the end of the nozzle cylinder 200 away from the nozzle head 100, and the output end of the drive assembly 500 is connected to the... The valve needle 300 is fixedly connected at one end away from the discharge port 110 for driving the valve needle 300 to move axially. The positioning member 400 is disposed in the injection space and located between the nozzle head 100 and the drive assembly 500. The positioning member 400 divides the injection space into a first space near the drive assembly 500 and a second space near the nozzle head 100. The positioning member 400 is provided with a first channel 410 for the valve needle 300 to pass through and a second channel 420 for the molten material to pass through. The first channel 410 is coaxially arranged with the discharge port 110 and is clearance-fitted with the valve needle 300.

[0021] The nozzle 100 delivers molten material to the mold outlet; the interior of the nozzle cylinder 200 is used to contain the molten material; the drive assembly 500 provides axial movement power to the valve needle 300, enabling the valve needle 300 to open or close the outlet 110 through axial movement, thereby controlling whether the molten material flows out; the first channel 410 on the positioning member 400 provides radial support and guidance during the movement stroke of the valve needle 300, ensuring the alignment of the valve needle 300 with the outlet 110; the second channel 420 ensures that the melt can smoothly flow from the first space into the second space, and finally be ejected from the outlet 110. By setting the first channel 410 on the positioning member 400 coaxially with the discharge port 110 and making the valve needle 300 clearance fit with the first channel 410, the valve needle 300 will be guided and corrected by the first channel 410 of the positioning member 400 during movement, ensuring that the valve needle 300 can always enter and exit the discharge port 110 at the correct angle and position, fundamentally avoiding collision between the valve needle 300 and the edge of the discharge port 110; eliminating lateral collision between the valve needle 300 and the nozzle head 100, reducing wear on the head of the valve needle 300 and the nozzle head 100, extending the service life of the valve needle 300, the nozzle head 100 and the mold, and reducing maintenance costs and the frequency of parts replacement.

[0022] During injection molding, the drive assembly 500 moves the valve needle 300 backward. The valve needle 300 first exits from the outlet 110, opening the flow channel. Under the injection pressure, the melt flows sequentially through the second channel 420 and the first space on the positioning member 400, finally entering the mold cavity through the opened outlet 110. When it is necessary to stop the discharge, the valve needle 300 moves forward under the drive assembly 500, and its head tightly inserts into and seals the outlet 110 on the nozzle head 100, preventing the melt from flowing out. During the retraction and forward movement, the rod of the valve needle 300 always slides within the first channel 410 of the positioning member 400. The axis of the first channel 410 always remains coaxial with the axis of the discharge port 110. When the valve needle 300 moves and becomes misaligned, its rod will contact the inner wall of the first channel 410 and be forcibly corrected back to a position consistent with the axis of the first channel 410. This ensures that the valve needle 300 can always be accurately guided to the center position of the discharge port 110 in the final stage of the closing stroke, thereby achieving accurate and collision-free closing. It should be noted that the structure and working principle of the drive assembly 500 and the valve needle 300 are existing technologies and will not be described in detail here.

[0023] In one embodiment, the first channel 410 is a first through hole, which extends along the axial direction of the positioning member 400 and connects the first space and the second space. The first through hole provides continuous radial support and guidance for the rod of the valve needle 300 from the first space to the second space, transforming the long cantilever structure of the valve needle 300 into a stable double-support structure. It can actively and forcibly correct any radial offset of the valve needle 300 caused by thermal deformation, processing errors, or force misalignment, ensuring that its axis is always aligned with the axis of the discharge port 110. This improves the positioning accuracy of the valve needle 300, reduces the collision between the valve needle 300 and the edge of the discharge port, and extends the service life of the discharge port and the valve needle 300.

[0024] When molten material flows from the first space to the second space, excessive flow resistance may occur, leading to blockage and slow flow rate, thus affecting injection molding efficiency. Therefore, in one embodiment, the second channel 420 includes multiple second through holes evenly arranged around the first through hole, connecting the first space and the second space. These multiple second through holes achieve multi-path flow diversion of the molten material, allowing it to be transported from the first space to the second space via multiple paths. This effectively disperses the flow of the molten material, reduces overall flow resistance, and allows the molten material to reach the outlet 110 more smoothly and quickly and be injected into the mold cavity. It also helps improve the uniformity of molten material filling, ensuring even distribution within the mold cavity, thereby improving the molding quality of the plastic part and reducing internal structural defects and appearance flaws caused by uneven molten material filling, better meeting the stringent quality requirements of precision injection molding.

[0025] When the molten material changes direction from the first space to flow into the second channel 420, the change in the flow direction may cause significant local stress, which can easily disrupt the uniform structure inside the molten material. Therefore, in one embodiment, the positioning member 400 is further provided with a first recess 430, which is located on the end face of the positioning member 400 facing the first space. The inlet of the second channel 420 is connected to the first recess 430. The first recess 430 forms a flow guide and buffer cavity, which can act as a confluence, gathering the dispersed molten material and buffering the flow of the molten material. This reduces the impact force generated when the flow direction of the molten material changes, allowing the molten material to smoothly turn and flow into the second channel 420, reducing the occurrence of flow dead zones, avoiding local accumulation and stagnation of the molten material, effectively reducing the generation of local stress, and ensuring the integrity of the internal structure of the molten material.

[0026] When molten material flows in, it may not be able to effectively concentrate and converge, easily resulting in a dispersed flow direction. Therefore, in one embodiment, the first recess 430 is disposed in the middle of the end face of the positioning member 400 facing the first space, and the width of the first recess 430 gradually increases from the direction near the nozzle 100 to the direction away from the nozzle 100. After the molten material enters the first recess 430, it is constrained by the gradually narrowing sidewall, and the flow direction is gradually corrected and concentrated. The flow velocity increases appropriately as the space narrows. The entire process achieves orderly guidance and state optimization of the molten material flow, allowing the molten material to flow into the second channel 420 in an ideal state, thereby ensuring the smooth and uniform flow of the molten material throughout the entire injection molding process.

[0027] At the moment the valve needle 300 opens, the high-pressure molten material may directly rush into the subsequent flow channel and the outlet 110 with a strong impact force, causing turbulence in the molten material flow. Therefore, in one embodiment, the positioning member 400 is also provided with a second recess 440, which is located on the end face of the positioning member 400 facing the second space. The outlets of the second channel 420 are all connected to the second recess 440. When the valve needle 300 opens, the high-pressure molten material flows rapidly from the second channel 420 towards the outlet 110. After the molten material enters the second recess 440, its internal space buffers and disperses the pressure of the molten material, changing the original situation where the high-pressure molten material directly impacts the subsequent flow channel. This allows the molten material to continue flowing towards the outlet 110 in a relatively stable and uniform pressure state after flowing out of the second recess 440, ultimately achieving stable injection, ensuring the uniformity and stability of molten material filling during injection molding, and improving product quality.

[0028] Molten material may enter subsequent flow channels with significant pressure fluctuations and unstable flow rates, causing disruption to the injection process. Therefore, in one embodiment, the second recess 440 is located at the center of the end face of the positioning member 400 facing the second space, and the width of the second recess 440 gradually increases from the direction away from the nozzle head 100 towards the direction closer to the nozzle head 100. This gradually increasing width structure can better accommodate and disperse the pressure shock generated by the instantaneous release of high-pressure molten material. As the molten material flows towards the nozzle head 100, the width gradually increases, providing more ample buffer space for the molten material, allowing for a smoother transition in flow rate and a more uniform pressure distribution. This makes the injection process more stable and orderly, effectively improving product quality and reducing defects in the appearance and internal structure of the plastic part caused by pressure shocks.

[0029] In one embodiment, the positioning element 400 is integrally formed with the nozzle cylinder 200. This integrally formed structure enhances the overall structural strength and stability, effectively resisting the influence of external factors such as molten material impact, temperature changes, and equipment vibration. It avoids a series of problems caused by loose component connections, ensuring that the positioning element 400 can always accurately position and guide the valve needle 300, guaranteeing the consistency of the valve needle 300's movement path with the center of the discharge port 110. This reduces the possibility of the valve needle 300 colliding with the edge of the discharge port 110, improving the reliability and stability of equipment operation.

[0030] In another embodiment, the positioning element 400 is detachably connected and fixed to the nozzle cylinder 200; the outer wall of the positioning element 400 is provided with an annular protrusion or external thread, and the inner wall of the nozzle cylinder 200 is provided with an annular groove matching the annular protrusion or an internal thread engaging with the external thread. When the positioning element 400 wears or is damaged due to long-term use, it can simply be removed from the nozzle cylinder 200 and replaced with a new positioning element 400. The operation is relatively simple, saving maintenance time and costs, enabling quick resumption of production and improving production efficiency. When regularly cleaning the nozzle structure, the positioning element 400 can be easily disassembled for thorough cleaning of its interior and all corners inside the nozzle cylinder 200, removing residual molten material, impurities, etc., ensuring the purity and smooth flow of the molten material during the next injection molding, which helps improve the quality of injection molded products.

[0031] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A nozzle structure, characterized in that, The device includes a nozzle head, a nozzle cylinder, a valve needle, a positioning element, and a drive assembly. The nozzle cylinder has an axially extending injection space. The nozzle head is located at one end of the nozzle cylinder and has a discharge port communicating with the injection space. The valve needle is axially movable within the injection space, and one end of the valve needle is used to cooperate with the discharge port to open or close the discharge port. The drive assembly is located at the end of the nozzle cylinder away from the nozzle head, and the output end of the drive assembly is fixedly connected to the end of the valve needle away from the discharge port, for driving the valve needle to move axially. The positioning element is located within the injection space and between the nozzle head and the drive assembly. The positioning element divides the injection space into a first space near the drive assembly and a second space near the nozzle head. The positioning element has a first channel for the valve needle to pass through and a second channel for the molten material to pass through. The first channel is coaxially arranged with the discharge port and has a clearance fit with the valve needle.

2. The nozzle structure according to claim 1, characterized in that, The first channel is a first through hole, which is provided to extend through the axial direction of the positioning member, and the first through hole connects the first space and the second space.

3. The nozzle structure according to claim 2, characterized in that, The second channel includes a plurality of second through holes, which are evenly arranged around the first through hole, and the second through holes connect the first space and the second space.

4. The nozzle structure according to claim 1, characterized in that, The positioning member is further provided with a first recess, which is disposed on the end face of the positioning member facing the first space, and the entrance of the second channel is connected to the first recess.

5. The nozzle structure according to claim 4, characterized in that, The first recess is disposed in the middle of the end face of the positioning member facing the first space, and the width of the first recess gradually increases from the direction close to the nozzle head to the direction away from the nozzle head.

6. The nozzle structure according to claim 1, characterized in that, The positioning member is also provided with a second recess, which is disposed on the end face of the positioning member facing the second space, and the outlet of the second channel is connected to the second recess.

7. The nozzle structure according to claim 6, characterized in that, The second recess is disposed in the middle of the end face of the positioning member facing the second space, and the width of the second recess gradually increases from the direction away from the nozzle head to the direction closer to the nozzle head.

8. The nozzle structure according to claim 1, characterized in that, The positioning component is integrally formed with the nozzle cylinder.

Images