Mould hot runner nozzle assembly
By adopting the design of a raised structure and vacuum insulation cavity in the hot runner mold, the problem of insulation cap accuracy is solved, the stable operation and cost reduction of the mold is achieved, and the service life and processing accuracy are improved.
Patent Information
- Application Number
- CN202421098198.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-17
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-05-17
AI Technical Summary
The processing accuracy of the heat insulation cap in existing hot runner molds is difficult to ensure, resulting in unstable use of the mold, high maintenance costs, and lack of unified standards, which affects the normal operation of the mold.
The insulating cap is replaced by a raised structure, so that the mouth core and the mouth head are in contact directly, and the temperature is transferred and sealed by adjusting the contact area between the projection and the slot. The insulating cap is cancelled and a vacuum insulating cavity is designed to maintain temperature stability. .
It reduces production and maintenance costs, improves the stability and service life of the mold, reduces the number of parts, simplifies processing difficulty, and ensures uniform temperature transfer and sealing effect.
Smart Images
Figure CN222245910U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of injection molds, and particularly relates to a mold hot runner nozzle assembly. Background Art
[0002] Hot runner mold is a system that uses a heating device to keep the melt in the runner in a molten state. Compared with traditional process molds, it has the advantages of short molding cycle and saving raw materials. In the hot runner mold, the nozzle assembly is an important part, including the nozzle 101 and the nozzle core 102. Please refer to Figure 1 There is a heat insulation cap 103 between the nozzle 101 and the mouth core 102. The heat insulation cap is a heating tube protection device used on the hot runner mold, which can effectively isolate the contact between the heating tube (which can be understood as the mouth core) and the mold, and the temperature of the heating tube can be adjusted through the heat insulation cap so that it can achieve an ideal heat conduction effect, thereby ensuring that the temperature of the mold rises evenly and reducing the probability of thermal runaway of the mold; it prevents the melt from penetrating into the vacuum suction port, thereby ensuring the vacuum degree of the mold and improving the quality and grade of the surface finished product; and the heat insulation cap can reduce the surface temperature of the mold, reduce the thermal stress and thermal fatigue of the mold, and extend the service life of the mold.
[0003] Therefore, the heat insulation cap is an important component for heating and conduction in mold production.
[0004] The heat insulation cap of the hot runner mold mentioned above is a high-precision component. The existing products have the following defects: 1. Errors are inevitable during processing, which causes the melt to penetrate between the heat insulation cap and the feed port after assembly, resulting in unclean punching when changing colors; 2. When the processing accuracy of the heat insulation cap cannot be guaranteed, the processed heat insulation cap is either too thick or too thin. When it is too thick, the heat insulation cap will squeeze the nozzle core, causing the mold edge of the mold to be squeezed and deformed. When it is too thin, the heat insulation cap will not contact completely with the nozzle core, making it difficult to transfer the temperature to the nozzle head; 3. The heat insulation cap is The hot runner mold is a consumable part that needs to be replaced frequently, which has high technical requirements for replacement and assembly. Improper assembly will cause more problems, so the later maintenance cost of the hot runner mold is also high; 4. There is no unified standard for thermal insulation caps at home and abroad, which leads to the fact that processing companies can only purchase and replace the manufacturer's thermal insulation caps after purchasing hot runner molds, otherwise the hot runner molds cannot continue to be used normally; 5. The existing thermal insulation cap is in the installation groove of the nozzle head, which makes the processing of the nozzle head more complicated, with more step grooves and high production costs.
[0005] In addition, due to the placement of the heat insulation cap, the installation space of the nozzle core is reduced, resulting in a reduction in the design thickness of the nozzle core. Under the long-term action of the melt (high temperature and high-speed flow erosion), the nozzle core is prone to cracking and has a short service life.
[0006] To sum up, how to use the hot runner mold normally without using the heat insulation cap has become a technical problem that needs to be solved urgently in the industry. Summary of the invention
[0007] The utility model aims to solve the existing technical problem and provide a mold hot runner nozzle assembly, which can normally use the hot runner mold without a heat insulation cap and ensure that various use parameters of the hot runner mold are within a normal standard range.
[0008] The technical solution adopted by the utility model to solve the above technical problems is:
[0009] The utility model discloses a mold hot runner nozzle assembly, comprising a nozzle head and a nozzle core, the nozzle head having a slot and a gate, the nozzle core being inserted in the slot, and the hot runner in the nozzle core is matched and connected with the gate; the end surface of the nozzle core facing the slot is provided with a protrusion, the protrusion is in surface-to-surface contact with the bottom surface of the slot, and a seal is achieved between the two.
[0010] The utility model eliminates the heat insulating cap between the nozzle core and the nozzle head, and instead uses a raised structure to achieve surface contact sealing between the nozzle core and the slot, which reduces the number of parts, which means a reduction in production costs, and at the same time, it also means a reduction in failure rate and improved stability. Surface contact sealing not only brings sealing, but also achieves heat transfer between the nozzle core and the nozzle head, that is, the temperature of the nozzle core can be transferred to the gate position of the nozzle head through the raised projection; the transfer temperature can be adjusted by the contact area between the raised projection and the bottom surface of the slot, so the bottom surface area of the raised projection can be adjusted during processing according to actual requirements. The larger the contact area, the more and faster the temperature transfer, and the higher the gate temperature. The smaller the contact area, the less and slower the temperature transfer, and the lower the gate temperature.
[0011] The protrusion is a body of revolution formed by rotating around the center line of the nozzle core with a right-angled trapezoid as the cross section, so that the outer side wall of the protrusion is an inclined surface inclined inwardly.
[0012] The center hole of the rotating body is actually the outlet of the nozzle core hot runner. Since the thickness of the protrusion is relatively thin, the inclined surface of the protrusion can provide support for the inner wall of the hot runner facing the protrusion, thereby improving the strength against melt flow erosion.
[0013] A vacuum heat-insulating cavity is formed between the mouth core and the slot.
[0014] The design of the vacuum insulation chamber is to ensure that the temperature of the nozzle core does not diffuse and prevent heat loss, thereby ensuring the state of the melt in the hot runner.
[0015] The outer wall of the mouth core matches the shape of the inner wall of the slot, and both are streamlined structures, including a first vertical section, an inclined section and a second vertical section connected in sequence, the protrusion is arranged on the end face of the first vertical section, and the bottom angle of the first vertical section is rounded; there is a chamfered corner between the first vertical section and the inclined section; the outer diameter of the second vertical section is larger than the outer diameter of the first vertical section, and there is a chamfered corner between the second vertical section and the inclined section.
[0016] The streamlined design reduces the difficulty of processing, thereby further reducing production costs and improving processing accuracy.
[0017] Gap 1 between the end face of the first vertical section and the bottom face of the slot and gap 2 between the first vertical section, the inclined section, the second vertical section and the side wall of the slot together form a vacuum insulation cavity, and the height h of gap 1 is greater than the width w of gap 2.
[0018] Since gap one is closer to the protrusion and the gate, the enlarged space can improve the vacuum insulation effect at this position, thereby improving the thermal insulation of the gate position, keeping the temperature at the gate position stable, and thus keeping the properties of the melt stable.
[0019] The width of the contact surface between the protrusion and the bottom surface of the slot is 0.5mm-1mm.
[0020] In summary, the beneficial effects of the utility model are:
[0021] Compared with the prior art, the hot runner nozzle assembly of the utility model eliminates the heat insulation cap and adopts a protruding structure, so that the nozzle core and the gate of the nozzle head can be directly contacted, so that the temperature of the nozzle core is directly transferred to the gate. At the same time, the surface contact seal between the protrusion and the slot also prevents the melt from entering the vacuum insulation cavity. The hot runner mold with reduced heat insulation caps reduces costs, improves stability, and reduces later maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a structural schematic diagram of the background technology;
[0023] Figure 2 It is a structural schematic diagram of the utility model having a mold hot runner nozzle assembly;
[0024] Figure 3 yes Figure 2 Enlarged view of part A. DETAILED DESCRIPTION
[0025] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:
[0026] See also Figures 1 to 3The utility model provides a mold hot runner nozzle assembly, including a nozzle head 1 and a nozzle core 2, the nozzle head 1 has a slot 3 and a gate 4, the gate 4 is a bell mouth, facing the hot runner 5 of the nozzle core 2 inserted in the slot 3, and the melt in the hot runner 5 can enter the mold cavity through the gate 4 well; the end face of the nozzle core 2 facing the slot 3 has a protrusion 6, and the protrusion 6 is in surface-to-surface contact with the bottom surface 7 of the slot 3, and a seal is achieved between the two.
[0027] The height of the protrusion 6 should not be too high, because there are certain requirements for the contact area between the protrusion 6 and the groove bottom surface 7 (usually, we will control the width of the contact surface between the protrusion 6 and the groove bottom surface 7 of the slot 3 within the range of 0.5mm-1mm). This results in the protrusion 6 being a thinner rotating body structure. Therefore, if the protrusion 6 is too high, its own pressure-bearing capacity will be weakened, and the high-temperature, high-pressure and high-speed melt in the hot runner 5 will cause the protrusion 6 to deform, resulting in the failure of the sealing effect.
[0028] In order to improve the strength of the protrusion 6 , the protrusion 6 of the present invention is a rotating body formed by rotating around the center line of the nozzle core 2 with a right-angled trapezoid as the cross section, so that the outer side wall of the protrusion 6 is an inwardly inclined slope 8 .
[0029] The central hole formed by the rotating body is actually the outlet of the hot runner 5 of the nozzle core 2, so the inclined surface 8 of the protrusion 6 can provide support force for the inner wall of the hot runner 5 facing the protrusion 6, thereby improving the ability to resist high temperature, high pressure and high speed of the melt.
[0030] The protrusion 6 is designed to reasonably transfer the temperature of the nozzle core 2 to the gate 4 and ensure that the temperature of the gate 4 meets the specified technical requirements, rather than to achieve contact sealing by directly contacting the end face of the nozzle core 2 with the bottom surface 7 of the slot 3. This practice will cause the temperature of the gate 4 to be too high, and then cause the melt in the gate 4 to carbonize.
[0031] The temperature transferred from the nozzle core 2 to the gate 4 can be adjusted by the contact area between the protrusion 6 and the bottom surface 7 of the slot 3. Therefore, the bottom area of the protrusion 6 can be adjusted during processing according to actual requirements. The larger the contact area, the more and faster the temperature is transferred, and the temperature of the gate 4 is higher. The smaller the contact area, the less and slower the temperature is transferred, and the temperature of the gate 4 is lower.
[0032] A vacuum heat-insulating cavity 9 is formed between the mouthpiece 2 and the slot 3 .
[0033] The vacuum heat-insulating chamber 9 is designed to ensure that the temperature of the nozzle core 2 does not diffuse and to prevent heat loss, thereby ensuring the state of the melt in the hot runner 5 .
[0034] For the convenience of processing, the outer wall of the mouth core 2 and the inner wall shape of the slot 3 are kept matched, both of which are streamlined structures, including a first vertical section 10, an inclined section 11 and a second vertical section 12 connected in sequence, the protrusion 6 is arranged on the end face of the first vertical section 10, and the bottom angle of the first vertical section 10 is rounded; there is a chamfer between the first vertical section 10 and the inclined section 11; the outer diameter of the second vertical section 12 is larger than the outer diameter of the first vertical section 10, and there is a chamfer between the second vertical section 12 and the inclined section 11.
[0035] The streamlined design reduces the difficulty of processing, thereby further reducing production costs and improving processing accuracy.
[0036] The gap 13 between the end face of the first vertical section 10 and the bottom face 7 of the slot 3 and the gap 2 14 between the first vertical section 10, the inclined section 11, the second vertical section 12 and the side wall of the slot 3 together form a vacuum insulation cavity 9, and the height h of the gap 13 is greater than the width w of the gap 2 14.
[0037] Since the gap 13 is closer to the protrusion 6 and the gate 4, the enlarged space can improve the vacuum insulation effect at this position, thereby improving the thermal insulation of the gate 4 position, so that the temperature at the gate 4 position remains stable, thereby keeping the properties of the melt stable.
[0038] In summary, the heat insulating cap is eliminated between the nozzle core 2 and the nozzle head 1 of the utility model, and the protrusion 6 structure is used instead to achieve surface contact sealing between the nozzle core 2 and the slot 3, which reduces the number of parts, which means a reduction in production costs, and at the same time, it also means a reduction in failure rate and an improvement in stability. The surface contact sealing between the protrusion 6 and the bottom surface 7 of the slot not only brings about sealing, but also realizes heat transfer between the nozzle core 2 and the nozzle head 1, that is, the temperature of the nozzle core 2 can be transferred to the gate 4 position of the nozzle head 1 through the protrusion 6; in addition, the nozzle core 2 is made of metal, and the metal has an expansion coefficient. After the nozzle core 2 is heated, the protrusion 6 will expand to a certain extent, and its outer wall is an inclined slope 8, so that the expansion of the protrusion 6 extends more along the height direction, and then the protrusion 6 and the bottom surface 7 of the slot 3 are more closely fitted, and the sealing is better.
[0039] The mold hot runner nozzle assembly provided in the embodiment of the utility model is introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation mode of the utility model. The description of the above embodiments is only used to help understand the technical solution disclosed by the utility model; at the same time, for general technical personnel in this field, according to the idea of the utility model, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as a limitation of the utility model.
Claims
1. A mold hot runner nozzle assembly, comprising a nozzle head and a nozzle core, characterized in that: The nozzle head has a slot and a gate, the nozzle core is inserted in the slot, and the hot runner in the nozzle core matches and penetrates the gate; the end surface of the nozzle core facing the slot has a protrusion, and the protrusion is in surface-to-surface contact with the bottom surface of the slot, and a seal is achieved between the two.
2. A mold hot runner nozzle assembly according to claim 1, characterized in that: The protrusion is a body of revolution formed by rotating around the center line of the nozzle core with a right-angled trapezoid as the cross section, so that the outer side wall of the protrusion is an inclined surface inclined inwardly.
3. A mold hot runner nozzle assembly according to claim 1 or 2, characterized in that: A vacuum heat-insulating cavity is formed between the mouth core and the slot.
4. The mold hot runner nozzle assembly according to claim 1, characterized in that: The outer wall of the mouth core matches the shape of the inner wall of the slot, and both are streamlined structures, including a first vertical section, an inclined section and a second vertical section connected in sequence, the protrusion is arranged on the end face of the first vertical section, and the bottom angle of the first vertical section is rounded; there is a chamfered corner between the first vertical section and the inclined section; the outer diameter of the second vertical section is larger than the outer diameter of the first vertical section, and there is a chamfered corner between the second vertical section and the inclined section.
5. A mold hot runner nozzle assembly according to claim 4, characterized in that: Gap 1 between the end face of the first vertical section and the bottom face of the slot and gap 2 between the first vertical section, the inclined section, the second vertical section and the side wall of the slot together form a vacuum insulation cavity, and the height h of gap 1 is greater than the width w of gap 2.
6. The mold hot runner nozzle assembly according to claim 1, characterized in that: The width of the contact surface between the protrusion and the bottom surface of the slot is 0.5mm-1mm.