Valve needle and hot runner system
By setting inserts with low thermal conductivity on the end surface of the valve needle, the adhesive problem caused by excessive temperature at the valve needle end is solved, the aesthetics of the product is maintained, and other performances of the valve needle will not be affected.
Patent Information
- Application Number
- CN202510040501.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-09
- Publication Date
- 2025-02-28
AI Technical Summary
In the prior art, the valve needle end has problems with adhesive due to excessive temperature, which affects the aesthetics of the product, and adjusting the temperature of the mold and the hot nozzle will lead to other process problems, narrowing the process adjustment window.
A valve needle is designed, and its end surface is equipped with an insert with a low thermal conductivity. The insert is made of PLAVIS material. By providing an insert in the accommodating groove of the valve needle body, the temperature of the valve needle end is reduced, thereby reducing the occurrence of adhesive material.
It effectively reduces the possibility of valve needle sticking, maintains the aesthetics of the product, and does not affect other performance of the valve needle, expands the window for process adjustment.
Smart Images
Figure CN119526702A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of hot runner systems, and in particular to a valve needle and a hot runner system provided with the valve needle. Background Art
[0002] At present, the temperature of the valve needle head in the needle valve hot runner is too high due to excessive shearing, which often causes the valve needle to stick to the gate of the product, resulting in an unsightly gate. Controlling the temperature of the mold and the hot nozzle will cause other problems in the product, narrowing the process adjustment window. Summary of the invention
[0003] The purpose of the present application is to provide a valve needle, wherein an insert with low thermal conductivity is arranged on the end face of the valve needle, thereby solving the problem of valve needle sticking due to excessively high temperature at the end of the valve needle in the prior art.
[0004] In order to achieve one of the above-mentioned purposes of the invention, an embodiment of the present application provides a valve needle, including a main body and an insert, wherein the end face of the main body used for sealing is provided with a receiving groove, the insert is arranged in the receiving groove, and the end face of the main body used for sealing is smoothly connected with the end face of the insert to form the sealing end face of the valve needle, and the thermal conductivity of the insert is lower than the thermal conductivity of the main body.
[0005] As a further improvement of an implementation mode of the present application, the insert is made of PLAVIS material.
[0006] As a further improvement of an embodiment of the present application, the sealing end face is a curved surface, and the projection of the sealing end face on the length direction of the valve needle has a ratio of the diameter of the insert to the diameter of the body at one end close to the insert of (0.65-0.85):1.
[0007] As a further improvement of an embodiment of the present application, the inner wall of the accommodating groove is provided with an internal thread, the insert is provided with an external thread, and the insert is connected to the main body through a threaded connection.
[0008] As a further improvement of an embodiment of the present application, the receiving groove includes a first receiving groove and a second receiving groove, the inner diameter of the first receiving groove is smaller than the inner diameter of the second receiving groove, and the inner wall of the first receiving groove is provided with the aforementioned internal thread;
[0009] The insert comprises a connecting portion and a filling portion, the outer diameters of which are matched with the inner diameters of the first accommodating groove and the second accommodating groove respectively, and the connecting portion is provided with the aforementioned external thread.
[0010] As a further improvement of an embodiment of the present application, the main body includes a sealing head with an insert on the end face, a pressure relief portion with a diameter larger than that of the sealing head, and a transition section connecting the sealing head and the pressure relief portion. The diameter of one end of the transition section connected to the pressure relief portion is the same as the diameter of the pressure relief portion, and the diameter gradually decreases to the same as the diameter of the sealing head in the direction extending toward the sealing head.
[0011] As a further improvement of an embodiment of the present application, the ratio of the diameter of the sealing head to the diameter of the pressure relief portion is (0.65-0.80):1.
[0012] As a further improvement of an embodiment of the present application, a material withdrawal groove extending along the length direction of the valve needle is provided near one end of the valve needle where the insert is provided.
[0013] As a further improvement of an embodiment of the present application, three material withdrawal grooves are provided, and the three material withdrawal grooves are evenly spaced along the circumference of the valve needle.
[0014] An embodiment of the present application further provides a hot runner system, including a diverter plate, a hot nozzle connected to the diverter plate, and a valve needle arranged in the hot nozzle, wherein the valve needle is the valve needle described above.
[0015] One or more technical solutions provided by this application have at least the following technical effects or advantages:
[0016] In the valve needle provided in the present application, a groove is formed at the end of the valve needle body, and an insert is arranged in the groove. The thermal conductivity of the insert is lower than that of the body. That is, the body is made of the material of a conventional valve needle, and the insert is made of a material with a relatively low thermal conductivity, thereby reducing the possibility of the valve needle sticking to the material and keeping the gate beautiful. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 is a side view of the valve needle in the embodiment of the present application.
[0018] Figure 2 yes Figure 1 Schematic cross-sectional view along line AA.
[0019] Figure 3 yes Figure 2 Enlarged view of point B in the middle.
[0020] Figure 4 yes Figure 1 End view of the middle valve needle.
[0021] Figure 5 It is a reference diagram for valve needle processing in the embodiment of the present application.
[0022] Figure 6 This is another reference diagram for processing the valve needle in the embodiment of the present application.
[0023] 1. Main body; 11. Sealing head; 111. Receiving groove; 1111. First receiving groove; 1112. Second receiving groove; 12. Transition section; 13. Decompression part; 14. Material withdrawal groove; 2. Insert; 21. Connection part; 22. Filling part; 3. Operation part. DETAILED DESCRIPTION
[0024] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0025] Terms such as "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like used herein to indicate spatial relative positions are used for the purpose of convenience to describe the relationship of one unit or feature relative to another unit or feature as shown in the accompanying drawings. Terms of spatial relative positions may be intended to include different orientations of the device in use or operation other than the orientation shown in the drawings.
[0026] For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
[0027] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0028] Furthermore, it should be understood that although the terms first, second, etc. may be used herein to describe various elements or structures, these described objects should not be limited by these terms. These terms are only used to distinguish these described objects from each other. For example, a first receiving slot may be referred to as a second receiving slot, and similarly, a second receiving slot may also be referred to as a first receiving slot, which does not deviate from the scope of protection of this application.
[0029] The present application embodiment provides a valve needle, such as Figures 1 to 6 As shown, it includes a main body 1 and an insert 2, the end face of the main body 1 used for sealing is provided with a receiving groove 111, the insert 2 is arranged in the receiving groove 111, and the end face of the main body 1 used for sealing is smoothly connected with the end face of the insert 2 to form the sealing end face of the valve needle, and the thermal conductivity of the insert 2 is lower than the thermal conductivity of the main body 1.
[0030] When the valve needle is sealed with glue, its sealing end face is in contact with the plastic. In the present application, a receiving groove 111 is formed on the end face of the valve needle body 1. Figure 3 , 4 In the embodiment, the receiving groove 111 is opened in the middle of the end face of the body 1 for sealing, and is coaxially arranged with the body 1, and the insert 2 with low thermal conductivity is arranged in the receiving groove 111. Although the insert 2 does not cover the entire sealing end face, but only in the middle of the sealing end face, when the mold is demoulded away from the sealing end face of the valve needle after sealing, the colloid tends to concentrate in the middle part under the action of the surface tension of the colloid, and the middle part of the sealing end face of the valve needle of the present application is the insert 2 with low thermal conductivity, so that the valve needle end face is not easy to be glued, and the aesthetics of the gate will not be affected.
[0031] Furthermore, when the valve needle is sealing near the gate, due to its slender shape, there is a possibility of the valve needle deviating from the gate. Since the insert 2 does not occupy the entire end face, the outer periphery of the sealing end face and the side of the valve needle adjacent to the sealing end face are still part of the main body 1. The material used is the higher hardness steel used by conventional valve needles. When it collides with the gate, the main body 1 has greater rigidity and is wear-resistant. Therefore, the valve needle of the present application can improve the problem of glue adhesion without reducing the original performance of the valve needle.
[0032] Preferably, the insert 2 is made of PLAVIS material. As a polymer material, PLAVIS has a better thermal expansion coefficient than the conventional metal material used as the valve needle. The valve needle works at high temperature. PLAVIS uses its higher thermal expansion coefficient to press against the inner wall of the receiving groove 111 of the main body 1 to avoid the formation of a gap between the main body 1 and the insert 2 to hide the glue.
[0033] In some embodiments, the sealing end surface is a curved surface, and the ratio of the diameter of the insert 2 to the diameter of the end of the body 1 close to the insert 2 in the projection in the length direction of the valve needle is (0.65-0.85):1. The curved sealing end surface can better reduce the resistance of the colloid, and the ratio of the diameter of the insert 2 to the end of the body 1 close to the insert 2 can ensure that the wall thickness of the accommodating groove 111 can maintain the strength required by the valve needle when sealing. On this basis, the insert 2 has as large an area as possible to prevent glue from sticking.
[0034] Regarding the connection relationship between the main body 1 and the insert 2, the present application provides an internal thread on the inner wall of the receiving groove 111, and the insert 2 is provided with an external thread, and the insert 2 is connected to the main body 1 through a threaded connection.
[0035] Specifically, Figure 5 In the figure, the receiving groove 111 includes a first receiving groove 1111 and a second receiving groove 1112, the inner diameter of the first receiving groove 1111 is less than the inner diameter of the second receiving groove 1112, and the inner wall of the first receiving groove 1111 is provided with the aforementioned internal thread; the insert 2 includes a connecting portion 21 and a filling portion 22, the outer diameter of which matches the inner diameter of the first receiving groove 1111 and the second receiving groove 1112, and the connecting portion 21 is provided with the aforementioned external thread.
[0036] For details about the connection method between the main body 1 and the insert 2, see Figure 5 , a valve needle body 1 made of conventional material is used, a first receiving groove 1111 and a second receiving groove 1112 are formed on the end surface thereof, and an internal thread is processed on the inner wall of the first receiving groove 1111. Figure 5 The workpiece includes the aforementioned connecting portion 21 and the filling portion 22 of the insert 2, and an operating portion 3 connected to the end of the filling portion 22 away from the connecting portion 21, and an external thread is processed outside the connecting portion 21. The operating portion 3 can be set to a polygon to assist workers in tightening the workpiece and the body 1. Figure 6 , the workpiece is partially removed, and the outer surface of the valve needle with the insert 2 can be processed into a desired structure like a conventional valve needle (such as removing Figure 6 The structure of the shaded area).
[0037] In some embodiments of the present application, the main body 1 includes a sealing head 11 with an insert 2 on the end face, a pressure relief portion 13 with a diameter larger than that of the sealing head 11, and a transition section 12 connecting the sealing head 11 and the pressure relief portion 13. The diameter of one end of the transition section 12 connected to the pressure relief portion 13 is the same as the diameter of the pressure relief portion 13, and the diameter gradually decreases to the same as the diameter of the sealing head 11 in the direction extending toward the sealing head 11.
[0038] The valve needle is passed through the transition section 12 near the sealing end to reduce the diameter of the valve needle, which can reduce the resistance, reduce the shear heat of the valve needle during operation, and further reduce the risk of valve needle sticking. The processing of the sealing head 11, the transition section 12 and the pressure relief part 13 can refer to Figure 6 , after the workpiece is installed as mentioned above, it is processed together with the operating part 3 of the workpiece.
[0039] Preferably, the ratio of the diameter of the sealing head 11 to the diameter of the pressure relief portion 13 is (0.65-0.80):1.
[0040] In some embodiments, a material withdrawal groove 14 extending along the length direction of the valve needle is provided at one end of the valve needle near the insert 2. When the valve needle is sealed with glue, excess glue will flow back, and the material withdrawal groove 14 provides space for the returned glue.
[0041] Preferably, three material withdrawal grooves 14 are provided, and the three material withdrawal grooves 14 are evenly spaced along the circumference of the valve needle. Figure 3 In the embodiment, the material withdrawal groove 14 extends from the transition section 12 through the pressure reducing portion 13 to the middle of the body 1 in the length direction.
[0042] An embodiment of the present application further provides a hot runner system, including a diverter plate, a hot nozzle connected to the diverter plate, and a valve needle arranged in the hot nozzle, wherein the valve needle is the valve needle mentioned above.
[0043] It should be understood that although this specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation mode may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.
[0044] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present application. They are not intended to limit the scope of protection of the present application. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present application should be included in the scope of protection of the present application.
Claims
1. A valve needle, characterized in that: It includes a main body and an insert, wherein the end face of the main body used for sealing is provided with a receiving groove, the insert is arranged in the receiving groove, and the end face of the main body used for sealing is smoothly connected with the end face of the insert to form the sealing end face of the valve needle, and the thermal conductivity of the insert is lower than the thermal conductivity of the main body.
2. The valve needle according to claim 1, characterized in that: The insert is made of PLAVIS material.
3. The valve needle according to claim 1, characterized in that: The sealing end surface is a curved surface, and the ratio of the diameter of the insert to the diameter of the body at one end close to the insert as projected in the length direction of the valve needle is (0.65-0.85):
1.
4. The valve needle according to claim 1, characterized in that The inner wall of the accommodating groove is provided with an internal thread, the insert is provided with an external thread, and the insert is connected to the body through a threaded connection.
5. The valve needle according to claim 4, characterized in that: The receiving groove comprises a first receiving groove and a second receiving groove, the inner diameter of the first receiving groove is smaller than the inner diameter of the second receiving groove, and the inner wall of the first receiving groove is provided with the aforementioned internal thread; The insert comprises a connecting portion and a filling portion, the outer diameters of which are matched with the inner diameters of the first accommodating groove and the second accommodating groove respectively, and the connecting portion is provided with the aforementioned external thread.
6. The valve needle according to claim 1, characterized in that: The main body includes a sealing head with an insert on the end surface, a pressure relief portion with a diameter larger than that of the sealing head, and a transition section connecting the sealing head and the pressure relief portion. The diameter of one end of the transition section connected to the pressure relief portion is the same as the diameter of the pressure relief portion, and the diameter gradually decreases to the same as the diameter of the sealing head in the direction extending toward the sealing head.
7. The valve needle according to claim 6, characterized in that The ratio of the diameter of the sealing head to the diameter of the pressure relief portion is (0.65-0.80):
1.
8. The valve needle according to claim 1, characterized in that The valve needle is provided with a material withdrawal groove extending along the length direction of the valve needle at one end close to the insert.
9. The valve needle according to claim 8, characterized in that There are three material withdrawal grooves, and the three material withdrawal grooves are evenly spaced along the circumference of the valve needle.
10. A hot runner system, comprising a manifold, a hot nozzle connected to the manifold, and a valve needle disposed in the hot nozzle, characterized in that: The valve needle is the valve needle according to any one of claims 1 to 9.