Sprue bush

Abstract

According to the sprue bush, only one inlet and only one outlet are formed in the two ends of a cooling flow channel of the sprue bush respectively, so that the flow of cooling fluid is monitored in real time only through the single inlet and the single outlet, accurate control over the cooling and temperature equalizing precision can be achieved, and then cooling and temperature equalizing are conducted on a main flow channel through the cooling flow channel; and the cooling efficiency is better, so that the cooling time is shortened, the overall forming period is further shortened, the forming yield of the optical element is improved, the size of the sprue bush can be kept fine and tiny, and the structural strength and the machining feasibility of the sprue bush are ensured.

Description

Technical Field

[0001] The invention relates to the technical field of injection molds, and in particular to a sprue sleeve, which can be especially applied to optical element molding molds. Background Art

[0002] In the field of injection molding, due to the small size of the gate bushing and the lack of cooling channels for the main runner, the mold cooling time cannot be shortened, resulting in a longer overall molding cycle. In addition, the material temperature distribution in the main runner also varies greatly, affecting the molding yield.

[0003] Furthermore, when setting up cooling water channels on the sprue bushing to cool the main flow channel, the compatibility of the main flow channel and the cooling channel must also be considered to ensure that the sprue bushing size is not too large while still having sufficient structural strength and manufacturability.

[0004] Therefore, how to cool the main channel while achieving uniform temperature in the long axis and transverse cross-sectional directions to improve the molding yield, and maintain the gate sleeve size, structural strength and processing feasibility is a problem that must be solved. Summary of the Invention

[0005] To this end, in order to solve the above problems, the present invention provides a sprue sleeve that can achieve uniform temperature through cooling the main channel and maintain the size of the sprue sleeve fine and small while ensuring its structural strength and processing feasibility.

[0006] To achieve the above objectives, the present invention provides the following technical solutions:

[0007] The present invention provides a sprue sleeve, comprising a main channel extending along a long axis and a cooling channel arranged around the main channel, the cooling channel comprising only one inlet for introducing a cooling fluid, only one outlet for leading out the cooling fluid, and a channel unit connected between the inlet and the outlet, the channel unit comprising an introduction section which surrounds a plurality of turns along the long axis of the main channel from the inlet and is used to introduce the cooling fluid, a turning section which is used to change the flow direction of the cooling fluid, and an outlet section which surrounds a plurality of turns along the long axis of the main channel and is used to lead the cooling fluid to the outlet, and satisfies 0.2≤DImin / BRmax≤9.0 and 1.0≤PII / BI≤18.0.

[0008] In one embodiment of the present invention, a material injection port is provided at one end of the main channel along the longitudinal direction.

[0009] In one embodiment of the present invention, the inlet, outlet and injection port are all located on the same side of the sprue bushing.

[0010] In one embodiment of the present invention, the flow direction of the cooling fluid in the introduction section is opposite to the flow direction of the cooling fluid in the outlet section.

[0011] In one embodiment of the present invention, the turning section is a Y-shaped structure, and the acute angle formed by two adjacent sides of the Y-shaped structure is 15 to 30 degrees.

[0012] In one embodiment of the present invention, there are two turning sections, which are 180 degrees apart from each other.

[0013] In the above-mentioned sprue bushing, the embodiment may further selectively satisfy any of the following conditions:

[0014] 1.0≤PIOmax / BO≤13.0;

[0015] 0.1≤(DImin-BRmin) / BI≤8.0;

[0016] 0.1≤(DOmax-BRmax) / BI≤23.0;

[0017] 1.0≤LR / (BI+PII)≤16.0;

[0018] 2.0≤DOmax / BRmax≤24.0.

[0019] Among them, BRmax is the maximum diameter of the main channel, BRmin is the minimum diameter of the main channel, BI is the maximum diameter of the introduction section, BO is the maximum diameter of the transverse section through which the cooling fluid in the lead-out section can flow, DImin is the minimum distance of the introduction section around the main channel, DOmax is the maximum distance of the lead-out section around the main channel, PII is the maximum distance between two adjacent circles of the introduction section around the main channel in the long axis direction, PIOmax is the maximum distance between two adjacent circles of the introduction section and the lead-out section around the main channel in the long axis direction, and LR is the maximum length of the main channel starting from the injection port and extending along the long axis direction.

[0020] The present invention surrounds the main channel with a cooling channel, and circles the main channel multiple times along the long axis direction from the inlet to the outlet, thereby ensuring that the temperature of the plastic melt in the main channel is evenly distributed in the long axis direction and the transverse cross-sectional direction. The cooling channel can be installed on an injection molding mold for optical components.

[0021] The cooling channel of the present invention is respectively provided with only one inlet and one outlet at both ends. Therefore, the flow change of the cooling fluid can be monitored only through a single inlet and a single outlet. This makes it easier to grasp the real-time cooling fluid flow rate. For example, when the temperature of the main channel is too high, the flow rate of the cooling fluid is increased, and more accurate control can be achieved in terms of the accuracy of the cooling temperature uniformity.

[0022] The flow channel unit of the present invention is formed by the inlet being surrounded by multiple circles along the long axis direction of the main flow channel and meeting the following conditional formula, thereby achieving temperature uniformity in the long axis direction and the transverse cross-sectional direction.

[0023] When the conditional formula (1) is satisfied: 0.2≤DImin / BRmax≤9.0, a uniform temperature distribution of the plastic melt in the transverse cross-sectional direction of the main channel can be achieved. In addition, by matching the maximum diameter of the main channel and setting a preferred minimum distance of the introduction section around the main channel, a better cooling efficiency can be ensured to shorten the cooling time. At the same time, the gate sleeve of the present invention still has sufficient structural strength under the premise of its small size.

[0024] When the conditional formula (2) is satisfied: 1.0≤PII / BI≤18.0, by adjusting the ratio between the maximum spacing between two adjacent circles of the introduction section around the main channel and parallel to the long axis and the maximum diameter of the transverse cross-section through which the cooling fluid in the introduction section can flow to meet the specific conditions, it is possible to ensure that the plastic melt in the main channel is stably dissipated along the plastic flow direction, and a better introduction section can be set in the long axis direction of the main channel according to the diameter of the introduction section and the spacing between the two adjacent circles to improve the cooling efficiency and shorten the cooling time. It is also possible to ensure that the temperature of the plastic melt in the long axis direction of the main channel is relatively uniform, thereby improving the molding yield.

[0025] Therefore, the present invention can achieve better cooling efficiency by using the sprue bushing with a cooling and temperature-uniform function, thereby reducing the cooling time and thus shortening the overall molding cycle, while improving the molding yield of the optical component and maintaining the sprue bushing in a fine and small size while ensuring its structural strength and processing feasibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Shown is a top view of the sprue bushing in the embodiment;

[0027] Figure 2 Shown Figure 1 Cross-sectional view of AA;

[0028] Figure 3 Shown Figure 1 Cross-sectional view of the middle BB;

[0029] Figure 4 Shown is a schematic diagram of the sprue bushing from another perspective in the embodiment;

[0030] Figure 5 The figure shows a schematic diagram of the temperature distribution of a quarter circle in the transverse cross-sectional direction of the main channel in the embodiment;

[0031] Figure 6 FIG. 1 is a schematic diagram showing the temperature distribution in the long axis direction of the main channel in the embodiment. DETAILED DESCRIPTION

[0032] To further illustrate various embodiments, the present invention is provided with accompanying drawings. These drawings form part of the present disclosure and are primarily used to illustrate the embodiments and, in conjunction with the relevant description in the specification, to explain the operating principles of the embodiments. By referring to these drawings, those skilled in the art will understand other possible embodiments and the advantages of the present invention. The components in the figures are not drawn to scale, and similar reference numerals are generally used to represent similar components.

[0033] The present invention will now be further described with reference to the accompanying drawings and specific embodiments.

[0034] Reference Figures 1 to 6 , this embodiment provides a gate sleeve for installation on an optical element injection molding mold.

[0035] like Figure 1 and Figure 2 As shown, the gate sleeve of this embodiment includes a main channel 1 extending along the long axis direction I and a cooling channel 2 wound around the main channel 1, and the main channel 1 is provided with an injection port 11 for injecting liquid plastic melt along its long axis direction I and at the upper end away from the mold core of the injection molding mold, and the lower end of the main channel 1 is used to connect to the branch channel of the injection molding mold.

[0036] The cooling channel 2 includes only one inlet 21 for introducing the cooling fluid, only one outlet 22 for leading out the cooling fluid, and a runner unit 23 connected between the inlet 21 and the outlet 22. At this time, the inlet 21, the outlet 22 and the injection port 11 are all located on the same side of the sprue bushing, which is conducive to the design of the runner unit 23 and can also maintain the size of the sprue bushing within a smaller range.

[0037] More specifically, Figure 1 、 Figure 3 and Figure 4 As shown, the flow channel unit 23 includes an introduction section 231 that surrounds the inlet 21 along the long axis direction I of the main channel 1 several times and is used to introduce the cooling fluid, a turning section 232 that is used to change the flow direction of the cooling fluid, and an outlet section 233 that surrounds the long axis direction I of the main channel 1 several times and is used to discharge the cooling fluid to the outlet 22.

[0038] The flow channel unit 23 of this embodiment meets the following requirements:

[0039] Conditional formula (1): 0.2≤DImin / BRmax≤9.0, and

[0040] Conditional expression (2): 1.0≤PII / BI≤18.0.

[0041] Among them, DImin is the minimum distance of the introduction section 231 around the main channel 1, BRmax is the maximum diameter of the main channel 1, PII is the maximum distance between two adjacent circles of the introduction section 231 around the main channel 1 and in the long axis direction I, and BI is the maximum diameter of the transverse section through which the cooling fluid in the introduction section 231 can flow.

[0042] In conditional formula (1), the relationship between the cooling effect and the size and structural strength of the gate sleeve is adjusted by coordinating the introduction section 231 with the maximum diameter of the main channel 1. For example, the closer the introduction section 231 is around the main channel 1, the better the cooling effect. If an appropriate distance is maintained between the introduction section 231 and the main channel 1, the gate sleeve can be guaranteed to have sufficient structural strength under the premise of its small size, and will not affect the size of the mold parts outside the gate sleeve. Therefore, the size of the entire injection mold is also relatively small.

[0043] When the ratio of DImin / BRmax is too large, it means that the introduction section 231 is far away from the main channel 1, and the temperature cannot be effectively reduced, which also increases the overall size of the gate bushing.

[0044] When the ratio of DImin / BRmax is relatively small, it means that the introduction section 231 is closer to the main runner 1, which can make it easier to cool the main runner 1. However, if the distance between the two is too close, the structural strength of the gate bushing will be insufficient due to the small space between the runners. Therefore, the two need to be matched with each other to design the optimal structure. In this way, uniform cooling can be achieved while maintaining the gate bushing's compact size, structural strength, and processing feasibility.

[0045] In conditional formula (2), when the diameter of the introduction section 231 is larger, the temperature of the main channel 1 drops faster; when the introduction section 231 surrounds the main channel 1 and the spacing in the direction parallel to the long axis direction I is shorter, more circles of the introduction section 231 can be surrounded to improve the cooling efficiency.

[0046] When the ratio of PII / BI is too large, it means that the distance between two adjacent circles is large, that is, the number of circles of the introduction section 231 around the main channel 1 is small, so the main channel 1 cannot be effectively cooled.

[0047] A smaller PII / BI ratio indicates a smaller spacing between adjacent turns, meaning the lead-in section 231 wraps around the main channel 1 more times, effectively reducing the temperature of the main channel 1. Furthermore, the diameter of the lead-in section 231 must be adjusted to achieve an appropriate ratio. By designing an optimal number of lead-in section 231 turns, the cooling effect is enhanced, achieving uniform cooling along the longitudinal axis I.

[0048] In summary, the cooling channel 2 of the present invention is provided with only one inlet 21 and only one outlet 22 at each end. Therefore, the real-time flow rate of the cooling fluid can be monitored only through the single inlet 21 and the single outlet 22. This makes it easier to grasp the real-time flow rate of the cooling fluid. For example, when the temperature in the main channel 1 is too high, the flow rate of the cooling fluid is increased, thereby achieving more accurate control on the accuracy of the cooling temperature uniformity.

[0049] The flow channel unit 23 of the present invention is formed by the inlet 21 being surrounded by multiple circles along the longitudinal direction I of the main channel 1 and satisfying the following conditional expressions (1) and (2), thereby achieving uniform temperature in the longitudinal direction I and the transverse cross-sectional direction.

[0050] When conditional formula (1) is satisfied, the temperature of the plastic melt in the transverse cross-sectional direction of the main channel 1 can be uniformly distributed. In addition, by matching the maximum diameter of the main channel 1 and setting a minimum distance of the preferred introduction section 231 around the main channel 1, better cooling efficiency can be ensured to shorten the cooling time. At the same time, the gate sleeve of the present invention still has sufficient structural strength under the premise of its small size.

[0051] When conditional formula (2) is satisfied, by adjusting the ratio between the maximum spacing between two adjacent circles of the introduction section 231 surrounding the main channel 1 and parallel to the long axis direction I and the maximum diameter of the transverse cross-section through which the cooling fluid in the introduction section 231 can flow to meet the specific conditions, it is possible to ensure that the plastic melt in the main channel 1 is stably dissipated along the plastic flow direction, and in the long axis direction I of the main channel 1, a better introduction section 231 can be set according to the diameter of the introduction section 231 and the spacing between the two adjacent circles to improve the cooling efficiency and shorten the cooling time. It is also possible to ensure that the temperature of the plastic melt in the long axis direction I of the main channel 1 is relatively uniform, thereby improving the molding yield.

[0052] Therefore, the present invention can achieve better cooling efficiency by using the sprue bushing with a cooling and temperature-uniform function, thereby reducing the cooling time and thus shortening the overall molding cycle, while improving the molding yield of the optical component and maintaining the sprue bushing in a fine and small size while ensuring its structural strength and processing feasibility.

[0053] Of course, in other embodiments, the preferred ratio of DImin / BRmax may also be 1.0-5.0, and the preferred ratio of PII / BI may also be 2.0-4.0.

[0054] In another preferred embodiment, the flow channel unit 23 satisfies the conditional formula (3): 1.0≤PIOmax / BO≤13.0, wherein BO is the maximum diameter of the transverse cross-section through which the cooling fluid in the lead-out section 233 can flow, and PIOmax is the maximum distance between two adjacent circles of the introduction section 231 and the lead-out section 233 around the main channel 1 and in the long axis direction I.

[0055] By satisfying conditional equation (3), the cooling efficiency of the runner unit 23 in the longitudinal direction I of the main channel 1 is improved, while maintaining the structural strength and processing feasibility of the sprue bushing. Furthermore, by adjusting the matching between the diameter and spacing of the lead-out sections 233 and optimizing the arrangement of the lead-in section 231 and the lead-out section 233, the cooling temperature uniformity efficiency is improved. However, if the sprue bushing is too small, the space between the runners will also become smaller, which will weaken the structural strength of the sprue bushing.

[0056] Of course, in other embodiments, the preferred ratio of PIOmax / BO may also be 1.0 to 3.0.

[0057] In another preferred embodiment, the runner unit 23 satisfies the conditional formula (4): 0.1≤(DImin-BRmin) / BI≤8.0, wherein BRmin is the minimum diameter of the main channel 1. This is conducive to better arranging the introduction section 231 around the main channel 1 to improve the cooling temperature uniformity efficiency in the transverse cross-sectional direction of the main channel 1, while maintaining the structural strength of the gate sleeve and its processing feasibility.

[0058] Further preferably, the runner unit 23 satisfies the conditional formula (5): 0.1≤(DOmax-BRmax) / BI≤23.0, wherein DOmax is the maximum distance of the lead-out section 233 around the main channel 1. This is further conducive to better arranging the lead-out section 233 around the main channel 1, so as to further improve the cooling temperature uniformity efficiency in the transverse cross-sectional direction of the main channel 1, while maintaining the structural strength of the gate sleeve and its processing feasibility.

[0059] Further preferably, the runner unit 23 satisfies the conditional formula (6): 1.0≤LR / (BI+PII)≤16.0, wherein LR is the maximum length of the main channel 1 starting from the injection port 11 and extending along the long axis direction I. This is conducive to better arranging the introduction section 231 around the main channel 1 to further improve the cooling and temperature uniformity efficiency in the transverse cross-sectional direction of the main channel 1, while maintaining the structural strength of the gate sleeve and its processing feasibility.

[0060] Of course, in other embodiments, the preferred ratio of (DImin-BRmin) / BI may also be 1.0-3.0, the preferred ratio of (DOmax-BRmax) / BI may also be 2.0-5.0, and the preferred ratio of LR / (BI+PII) may also be 1.0-3.0.

[0061] In another preferred embodiment, the runner unit 23 satisfies the conditional formula (7): 2.0≤DOmax / BRmax≤24.0, wherein DOmax is the maximum distance of the lead-out section 233 around the main runner 1. This is beneficial to increasing the cooling efficiency of the main runner 1 and maintaining a small gate sleeve size.

[0062] Of course, in other embodiments, the preferred ratio of DOmax / BRmax may also be 2.0 to 10.0.

[0063] In another preferred embodiment, the flow direction of the cooling fluid in the introduction section 231 is opposite to the flow direction of the cooling fluid in the outlet section 233. This is beneficial to the design of the flow channel unit 23 and can also ensure that the main channel 1 is evenly cooled in its transverse cross-sectional direction.

[0064] In another preferred embodiment, Figure 3 and Figure 4 As shown, the turning section 232 is a Y-shaped structure, and the acute angle formed by two adjacent sides of the Y-shaped structure is 15 to 30 degrees. There are two turning sections 232, and they are 180 degrees apart from each other.

[0065] When two adjacent acute angles are larger, the cooling fluid will flow more easily. However, if the acute angle is too large, it will also limit the space of the runner unit 23 provided in the long axis direction I. Therefore, the optimal acute angle is 15 to 30 degrees. This is conducive to the design of the runner unit 23, improves the cooling temperature uniformity efficiency, and maintains the strength and processing feasibility of the gate sleeve.

[0066] In addition, the relevant parameters of the sprue bushing of this specific embodiment adopt the actual values shown in Table 1, and the plastic melt is injected into the main channel 1, and the temperature distribution of the main channel 1 area in the sprue bushing is measured. Figure 5 and Figure 6 As shown, Figure 5 The figure shows the temperature distribution in the transverse cross-section direction of the main channel. Figure 6 Shown is a schematic diagram of the temperature distribution in the long axis direction of the main channel.

[0067] Table 1

[0068]

[0069]

[0070] like Figure 5 As shown, due to the frictional heat generated by the plastic melt and the inner wall of the main channel 1, the edge temperature corresponding to the inner wall of the main channel 1 is higher than the center temperature of the main channel 1, but the actual difference is less than 0.5 degrees. Therefore, the temperature of the plastic melt in the main channel 1 in its transverse cross-section direction is still evenly distributed.

[0071] like Figure 6 As shown, the difference between the maximum temperature and the minimum temperature of the plastic melt in the main channel 1 is within 1.5 degrees. Therefore, the temperature of the plastic melt in the main channel 1 in the long axis direction I is also uniformly distributed.

[0072] Of course, in other embodiments, DImin may also be selected within the range of 4.5 to 9.0 mm, and preferably 4.5 to 7.0 mm; BRmax may also be selected within the range of 1.8 to 10.0 mm, and preferably 1.8 to 6.0 mm; BI may also be selected within the range of 1.0 to 5.0 mm, and preferably 2.0 to 3.0 mm; PII may also be selected within the range of 4.0 to 18.0 mm, and preferably 7.0 to 9.0 mm; PIOmax may also be selected within the range of 3.0 to 13.0 mm. 0mm, and it is preferably 4.0-5.0mm; BO can also be selected in the range of 1.0-5.0mm, and it is preferably 2.0-3.0mm; BRmin can also be selected in the range of 1.0-4.0mm, and it is preferably 1.0-2.5mm; DOmax can also be selected in the range of 10.0-24.0mm, and it is preferably 10.0-12.0mm; LR can also be selected in the range of 14.0-80.0mm, and it is preferably 14.0-16.0mm.

[0073] Although the present invention has been particularly shown and described in conjunction with preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made to the present invention without departing from the spirit and scope of the invention as defined in the appended claims, and all such changes are within the scope of protection of the present invention.

Claims

1. A sprue bushing, characterized in that: It includes a main channel extending along a long axis direction and a cooling channel arranged around the main channel; The cooling channel includes only one inlet for introducing a cooling fluid, only one outlet for leading out the cooling fluid, and a channel unit connected between the inlet and the outlet; The flow channel unit includes an introduction section that is arranged along the longitudinal direction of the main channel from the inlet for a plurality of turns and is used to introduce the cooling fluid, a turning section that is used to change the flow direction of the cooling fluid, and an outlet section that is arranged along the longitudinal direction of the main channel for a plurality of turns and is used to lead the cooling fluid to the outlet. And it satisfies 0.2≤DImin / BRmax≤9.0 and 1.0≤PII / BI≤18.0, wherein DImin is the minimum distance of the introduction section around the main channel, BRmax is the maximum diameter of the main channel, PII is the maximum distance between two adjacent circles of the introduction section around the main channel in the long axis direction, and BI is the maximum diameter of the introduction section.

2. The sprue bushing according to claim 1, wherein: It further satisfies 1.0≤PIOmax / BO≤13.0, wherein BO is the maximum diameter of the transverse cross-section through which the cooling fluid can flow in the lead-out section, and PIOmax is the maximum distance between two adjacent circles of the lead-in section and the lead-out section around the main channel in the direction of the major axis.

3. The sprue bushing according to claim 1, wherein: More satisfied with 0.1≤(DImin-BRmin) / BI≤ 8.0, where BRmin is the minimum diameter of the main channel.

4. The sprue bushing according to claim 1, wherein: It further satisfies 0.1≤(DOmax-BRmax) / BI≤23.0, wherein DOmax is the maximum distance of the lead-out section around the main channel.

5. The sprue bushing according to claim 1, wherein: The main channel is provided with an injection port at one end thereof along the long axis; the gate sleeve further satisfies 1.0≤LR / (BI+PII)≤16.0, wherein LR is the maximum length of the main channel starting from the injection port and along the long axis.

6. The sprue bushing according to claim 1, wherein: It further satisfies 2.0≤DOmax / BRmax≤24.0, wherein DOmax is the maximum distance of the lead-out section around the main channel.

7. The sprue bushing according to claim 1, wherein: A material injection port is provided at one end of the main channel along the long axis direction, and the inlet, the outlet and the material injection port are all located on the same side of the sprue sleeve.

8. The sprue bushing according to claim 1, wherein: The flow direction of the fluid in the introduction section is opposite to the flow direction of the fluid in the outlet section.

9. The sprue bushing according to claim 1, wherein: The turning section is a Y-shaped structure, and the acute angle formed by two adjacent sides of the Y-shaped structure is 15 to 30 degrees.

10. The sprue bushing according to claim 1, wherein: There are two turning sections, which are 180 degrees apart from each other.

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