CN112172048A

CN112172048A - Nozzle assembly and needle valve hot runner system

Info

Publication number: CN112172048A
Application number: CN202011008758.1A
Authority: CN
Inventors: 张志刚; 贺立明; 王艳云; 董鹏鹏
Original assignee: Shenzhen Mould Tip Technology Co ltd
Current assignee: Shenzhen Mould Tip Technology Co ltd
Priority date: 2020-09-23
Filing date: 2020-09-23
Publication date: 2021-01-05

Abstract

The invention discloses a nozzle assembly and a needle valve hot runner system, which comprise a nozzle and a heat insulation assembly, wherein a valve needle hole is arranged in the nozzle; the heat insulation assembly comprises an outer sleeve and a water conveying sleeve, the outer sleeve is sleeved at the glue outlet end of the nozzle, the water conveying sleeve is sleeved outside the outer sleeve, a first heat insulation cavity is formed between the outer sleeve and the water conveying sleeve, and a cooling water channel is arranged on the water conveying sleeve. The invention can reduce the heat loss speed of the nozzle, keep the nozzle at a higher temperature and ensure that the rubber material is in a molten state; meanwhile, the heat received by the sprue area from the nozzle is reduced, the temperature of the sprue area is not too high, and the phenomenon of delayed solidification of melt in the sprue area is effectively relieved.

Description

Nozzle assembly and needle valve hot runner system

Technical Field

The invention relates to the field of hot runner molds, in particular to a nozzle assembly and a needle valve hot runner system.

Background

Currently, in the hot runner mold industry, a needle valve hot runner system is generally used due to the advantages of saving raw materials, beautifying a glue opening, reducing a molding period, improving the appearance of a product and the like. However, for plastic products made of different plastics and having higher requirements on appearance, because the temperature of the nozzle is higher, the heat of the nozzle is easily conducted to the surface of the mold, so that the local temperature of a sprue area of the mold is higher, the melt at a glue opening of the plastic product is solidified in a delayed manner in the cooling process, color difference and bright circles can be left on the surface of the product, and the appearance of the product is influenced.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a needle valve hot runner system which can avoid heat loss of a nozzle and can reduce the temperature of a sprue area.

The invention further provides a needle valve hot runner system.

In a first aspect, an embodiment of the present invention provides a nozzle assembly comprising: the nozzle is internally provided with a valve needle hole; the heat insulation assembly comprises an outer sleeve and a water conveying sleeve, the outer sleeve is arranged at the glue outlet end of the nozzle, the water conveying sleeve is arranged outside the outer sleeve, a first heat insulation cavity is formed between the outer sleeve and the water conveying sleeve, and the water conveying sleeve is provided with a cooling water channel.

The nozzle component of the embodiment of the invention at least has the following beneficial effects: the outer sleeve is sleeved at the glue outlet end of the nozzle, the water conveying sleeve is sleeved outside the outer sleeve, and a first heat insulation cavity is formed between the outer sleeve and the water conveying sleeve and can reduce the loss speed of heat of the nozzle, so that the nozzle is kept at a higher temperature and the glue is ensured to be in a molten state; in addition, in unit time, the heat received by the sprue area from the nozzle is reduced, the temperature of the sprue area is not too high, and the phenomenon of delayed solidification of the melt in the sprue area is effectively relieved; in addition, the water conveying sleeve is provided with a cooling water channel, after the cooling water channel is communicated with an external water source, the water conveying sleeve can be cooled, heat emitted by the nozzle is taken away by cooling water and is not easily conducted to a pouring gate area, and the problem that a melt is solidified in a delayed mode in the pouring gate area is further avoided.

According to other embodiments of the nozzle assembly of the present invention, the first insulating chamber is further provided with an insulating ring, an inner annular surface of the insulating ring is connected with the outer sleeve, and an outer annular surface of the insulating ring is connected with the water transporting sleeve.

According to other embodiments of the nozzle assembly of the present invention, the heat insulating ring is an annular projection formed on an outer surface of the outer sleeve.

In accordance with other embodiments of the nozzle assembly of the present invention, a second insulated chamber is formed between the outer sleeve and the nozzle.

According to other embodiments of the invention, the water transport sleeve comprises a first water transport sleeve and a second water transport sleeve, the second water transport sleeve is sleeved outside the jacket, the first water transport sleeve is arranged at one end of the second water transport sleeve close to the glue outlet end of the nozzle, and the cooling water channel is an annular cavity formed between the first water transport sleeve and the second water transport sleeve.

According to other embodiments of the nozzle assembly of the present invention, the outer surface of the second water jacket is provided with a water inlet and a water outlet, both of which are in communication with the annular cavity.

According to the nozzle assembly of other embodiments of the present invention, the heat insulation assembly further includes a sealing ring, the sealing ring is disposed on the glue outlet side of the nozzle, the glue outlet of the nozzle is located in an area enclosed by the sealing ring, and two side surfaces of the sealing ring respectively abut against the nozzle and the water transport sleeve.

According to other embodiments of the invention, the nozzle is provided with an annular clamping groove, the sealing ring is provided with a clamping ring, and the clamping ring is clamped in the annular clamping groove.

Nozzle assemblies according to further embodiments of the present invention further include a heating element coated on an outer circumferential surface of the nozzle.

In a second aspect, an embodiment of the present invention provides a needle valve hot runner system, which includes the above nozzle assembly, and further includes a flow distribution plate, a needle, and a driving device, wherein a flow passage is disposed in the flow distribution plate, the flow passage is communicated with the needle hole, the needle is inserted into the needle hole, and the driving device can drive the needle to slide along the needle hole.

The needle valve hot runner system provided by the embodiment of the invention at least has the following beneficial effects: by using the nozzle assembly, the nozzle can be kept at a higher temperature, and the rubber material is ensured to be in a molten state; meanwhile, in unit time, the heat received by the sprue area from the nozzle is reduced, the temperature of the sprue area is not too high, and the phenomenon of delayed solidification of the melt in the sprue area is effectively relieved.

Drawings

FIG. 1 is a cross-sectional view of a needle valve hot runner system of some embodiments;

FIG. 2 is an enlarged schematic view of region I of FIG. 1;

FIG. 3 is a top view of the outer cover of FIG. 1;

FIG. 4 is a cross-sectional view taken along section A-A of FIG. 3;

FIG. 5 is a perspective view of the second water jacket of FIG. 1;

FIG. 6 is a top view of the second water jacket of FIG. 1;

FIG. 7 is a cross-sectional view taken along section B-B of FIG. 6;

fig. 8 is a perspective view of the first water transporting jacket of fig. 1;

FIG. 9 is a top view of the first water jacket of FIG. 1;

fig. 10 is a cross-sectional view of fig. 9 taken along section C-C.

Detailed Description

The concept and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments to fully understand the objects, features and effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention.

In the description of the embodiments of the present invention, if an orientation description is referred to, for example, the orientations or positional relationships indicated by "upper", "lower", "front", "rear", "left", "right", etc. are based on the orientations or positional relationships shown in the drawings, only for convenience of describing the present invention and simplifying the description, but not for indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

In the description of the embodiments of the present invention, if a feature is referred to as being "disposed", "fixed", "connected", or "mounted" to another feature, it may be directly disposed, fixed, or connected to the other feature or may be indirectly disposed, fixed, connected, or mounted to the other feature. In the description of the embodiments of the present invention, if "a number" is referred to, it means one or more, if "a plurality" is referred to, it means two or more, if "greater than", "less than" or "more than" is referred to, it is understood that the number is not included, and if "greater than", "lower" or "inner" is referred to, it is understood that the number is included. If reference is made to "first" or "second", this should be understood to distinguish between features and not to indicate or imply relative importance or to implicitly indicate the number of indicated features or to implicitly indicate the precedence of the indicated features.

First embodiment

Referring to fig. 1, fig. 1 is a cross-sectional view of a needle valve hot runner system of some embodiments. The nozzle assembly of the first embodiment comprises a nozzle 200 and an insulating assembly, wherein the insulating assembly comprises a water jacket 100 and an outer jacket 300. The nozzle 200 has a needle hole 240 formed therein, and the needle hole 240 penetrates the nozzle 200 in the up-down direction. Valve needle bore 240 is used to deliver the sizing material in a molten state and for passage of valve needle 700. The outer sleeve 300 is sleeved on the glue outlet end of the nozzle 200 (the lower end of the nozzle 200 is the glue outlet end). The water transport sleeve 100 is sleeved outside the jacket 300, a first heat insulation cavity 320 is formed between the jacket 300 and the water transport sleeve 100, the first heat insulation cavity 320 is filled with air, and the water transport sleeve 100 is provided with a cooling water channel 130.

Because the heat conduction speed of air is generally lower than the heat conduction speed of solid, compare in overcoat 300 and fortune water jacket 100 direct contact, the heat of overcoat 300 is difficult to give off on fortune water jacket 100 to reduce the thermal loss speed of nozzle 200 that is located overcoat 300, nozzle 200 can keep at higher temperature, and the sizing material is in the molten state all the time, and it can go on smoothly to mould plastics. In addition, the heat received by the sprue area from the outer sleeve 300 (i.e., the nozzle 200) is reduced in unit time, the temperature of the sprue area is not too high, and the phenomenon of delayed solidification of the melt in the sprue area is effectively relieved.

The water transporting sleeve 100 is provided with a cooling water channel 130. After the cooling water channel 130 is communicated with an external water source, the water conveying sleeve 100 can be cooled, heat emitted by the nozzle 200 is taken away by cooling water and is not easily conducted to a pouring gate area, and the problem that a melt is solidified in the pouring gate area in a delayed mode is further avoided. In addition, the first insulating chamber 320 separates the water jacket 100 from the jacket 300, and prevents the heat of the jacket 300 from being excessively dissipated to the water jacket 100, thereby reducing the adverse effect of the cooling water passage 130.

Second embodiment

The nozzle assembly of the second embodiment is an improvement over the nozzle assembly of the first embodiment. Referring to fig. 1, 3, 4, 6 and 7, fig. 3 is a plan view of the outer cover 300 of fig. 1, fig. 4 is a sectional view of fig. 3 taken along a-a section, fig. 6 is a plan view of the second water jacket 120 of fig. 1, and fig. 7 is a sectional view of fig. 6 taken along B-B section. To form the first insulation chamber 320, a first receiving chamber 124 (refer to fig. 7) is formed in the water jacket 100, and the outer jacket 300 is inserted into the first receiving chamber 124, and the outer diameter of the outer jacket 300 is smaller than the inner diameter of the first receiving chamber 124, thereby forming the first receiving chamber 124 between the water jacket 100 and the outer jacket 300.

To stabilize the shape of the first receiving cavity 124, an insulating ring 310 is provided. The insulating ring 310 is located in the first insulating chamber 320, the inner annular surface of the insulating ring 310 is connected to the outer jacket 300, and the outer annular surface of the insulating ring 310 is connected to the water jacket 100. Therefore, the heat insulation ring 310 forms a stable support between the water jacket 100 and the outer jacket 300, the heat insulation ring 310 can prevent the outer jacket 300 from shaking in the first accommodation cavity 124, and the shape of the first accommodation cavity 124 can be kept stable.

In the present embodiment, two heat insulation rings 310 are provided, and the two heat insulation rings 310 are spaced apart from each other. By providing two heat insulation rings 310, the first accommodating cavity 124 is more stable and is not easy to deform. In other embodiments, the number of the heat insulation rings 310 may be more, such as three, four or five, depending on the size of the water jacket 100 and the jacket 300 in the vertical direction.

In addition, because the water conveying sleeve 100 is only contacted with the outer sleeve 300 through the heat insulation ring 310, the contact area between the water conveying sleeve 100 and the outer sleeve 300 is small, the heat transfer speed between the water conveying sleeve 100 and the outer sleeve 300 is small, the heat dissipation speed of the nozzle 200 is favorably reduced, and the temperature of a sprue area is reduced.

The connection between the inner ring surface of the heat insulating ring 310 and the outer jacket 300 may be a simple contact or an adhesive, or may be integrally connected. The outer ring surface of the heat insulation ring 310 is connected with the water jacket 100 in the same way.

Third embodiment

The nozzle assembly of the third embodiment is an improvement over the nozzle assembly of the second embodiment. Referring to fig. 1, 4 and 7, the insulating ring 310 is an annular protrusion formed on the outer surface of the outer jacket 300, that is, the insulating ring 310 is a part of the outer jacket 300, and the insulating ring 310 is integrally provided with the outer jacket 300. Compared with the independent heat insulation ring 310, the heat insulation ring 310 does not need to be additionally clamped during installation, and a separate installation structure does not need to be designed for the heat insulation ring 310, so that the installation step of the heat insulation ring 310 can be simplified, and the installation time can be saved. In addition, the insulating ring 310 is disposed on the outer surface of the outer jacket 300, which facilitates the processing (e.g., machining) of the insulating ring 310.

Fourth embodiment

The nozzle assembly of the fourth embodiment is an improvement over the nozzle assembly of the first embodiment. Referring to fig. 1 and 4, in order to fit the outer cap 300 on the lower end of the nozzle 200, a second receiving chamber 350 (refer to fig. 4) is formed in the outer cap 300, and the nozzle 200 is inserted into the second receiving chamber 350. To further reduce the rate of heat loss from nozzle 200, a second insulated chamber 330 is formed between jacket 300 and nozzle 200. The second insulating chamber 330 is filled with air and the jacket 300 is not in direct contact with the nozzle 200, thereby reducing the rate of heat loss from the nozzle 200 and maintaining the nozzle 200 at a higher temperature.

Fifth embodiment

The nozzle assembly of the fifth embodiment is an improvement over the nozzle assembly of the first embodiment. Referring to fig. 1, 7, 9 and 10, fig. 9 is a plan view of the first water transporting jacket 110 of fig. 1, and fig. 10 is a sectional view of fig. 9 taken along a section C-C. The water conveying sleeve 100 comprises a first water conveying sleeve 110 and a second water conveying sleeve 120, the second water conveying sleeve 120 is sleeved outside the jacket 300, the first water conveying sleeve 110 is arranged at one end of the second water conveying sleeve 120 close to the glue outlet end of the nozzle 200, namely the first water conveying sleeve 110 is sleeved at the lower end of the second water conveying sleeve 120, and the cooling water channel 130 is an annular cavity formed between the second water conveying sleeve 120 and the first water conveying sleeve 110.

In order to sleeve the first water transporting sleeve 110 on the lower end of the second water transporting sleeve 120, a third accommodating cavity 115 is opened in the first water transporting sleeve 110, and the lower end of the second water transporting sleeve 120 is inserted into the third accommodating cavity 115. Thus, the outer surface of the second water transporting sleeve 120 and the inner surface of the third receiving cavity 115 form an annular cavity. After the annular cavity is communicated with an external water source, all parts of the first water conveying sleeve 110 in the circumferential direction are cooled, because the first water conveying sleeve 110 is sleeved at the lower end of the second water conveying sleeve 120, the second water conveying sleeve 120 is sleeved at the lower end of the nozzle 200, and the lower end of the nozzle 200 is the part closest to the sprue area, the heat of the first water conveying sleeve 110 is taken away by cooling water, the heat emitted from the first water conveying sleeve 110 to the sprue area is directly reduced, the temperature of the sprue area is not too high, and the phenomenon of delayed solidification of a melt in the sprue area is effectively relieved.

Referring to fig. 1 and 2, in order to prevent cooling water from leaking from a gap between the lower end of the second water transporting jacket 120 and the inner surface of the third receiving chamber 115, a first annular groove 122 is formed on the lower end surface of the second water transporting jacket 120, and a first sealing ring is disposed in the first annular groove 122. The inner surface of the third receiving chamber 115 and the second water transporting jacket 120 clamp the first packing, so that the lower end of the second water transporting jacket 120 is sealed with the inner surface of the third receiving chamber 115.

In other embodiments, the lower end of the water jacket 100 may be formed with a spiral groove, and a water pipe is inserted into the spiral groove and connected to a water source. This also cools the lower end of the water jacket 100.

Referring to fig. 4, 7 and 10, in order to allow the molten adhesive to flow out of the nozzle 200, a second opening 340 is formed at the lower end of the second receiving chamber 350, a first opening 123 (see fig. 7) is formed at the lower end of the first receiving chamber 124, and a sealant sealing opening 113 is formed at the lower end of the third receiving chamber 115. After flowing out from the lower end of the valve needle hole 240, the melt adhesive sequentially passes through the second opening 340, the first opening 123 and the adhesive sealing opening 113 and enters the mold, and the lower end of the valve needle 700 is matched with the adhesive sealing opening 113 to realize adhesive feeding and adhesive sealing.

Sixth embodiment

The nozzle assembly of the sixth embodiment is an improvement over the nozzle assembly of the fifth embodiment. Referring to fig. 1, 5, 7 and 8, the outer surface of the second water transporting jacket 120 is provided with a water inlet 125 and a water outlet 127, and the water inlet 125 and the water outlet 127 are both grooves axially formed in the outer surface of the second water transporting jacket 120. The first water conveying sleeve 110 is provided with a first notch 112 and a second notch 114, and the first notch 112 and the second notch 114 are both communicated with the annular cavity. After the first water transporting sleeve 110 is sleeved on the lower end of the second water transporting sleeve 120, the first notch 112 is aligned with the water inlet 125, and the second notch 114 is aligned with the water outlet 127. Thus, both the water inlet 125 and the water outlet 127 communicate with the annular cavity.

By providing the water inlet 125 and the water outlet 127 on the outer surface of the second water jacket 120, the external cooling water line only needs to be guided to the outer surface of the second water jacket 120 to realize the water inlet and outlet of the annular cavity. After the nozzle assembly is installed on the die, an external water source can be conveniently and quickly communicated with the annular cavity.

Referring to fig. 5 and 8, in order to align the first notch 112 with the water inlet 125 and the second notch 114 with the water outlet 127, a first key groove 116 is further provided on the outer surface of the first water jacket 110, and a second key groove 128 is provided on the outer surface of the second water jacket 120. The first key slot 116 is aligned with the second key slot 128 and the key is inserted, and the first notch 112 is aligned with the water inlet 125 and the second notch 114 is aligned with the water outlet 127.

Seventh embodiment

The nozzle assembly of the seventh embodiment is an improvement of the nozzle assembly of the first embodiment. Referring to fig. 1 and 2, the insulation assembly further comprises a sealing ring 900, the sealing ring 900 being arranged on the glue outlet side of the nozzle 200, i.e. the sealing ring 900 is located on the lower side of the nozzle 200. The glue outlet of the nozzle 200 is positioned in the area enclosed by the sealing ring 900, the section of the sealing ring 900 is L-shaped, the inner side surface of the sealing ring 900 is abutted against the lower end of the nozzle 200, and the lower surface of the sealing ring 900 is abutted against the water conveying sleeve 100.

The sealing ring 900 is respectively abutted against the lower end of the nozzle 200 and the water conveying sleeve 100, namely the sealing ring 900 seals a gap between the lower end of the nozzle 200 and the water conveying sleeve 100, the glue outlet of the nozzle 200 is positioned in an area enclosed by the sealing ring 900, and the sealing ring 900 can prevent molten glue from flowing out from the gap between the lower end of the nozzle 200 and the water conveying sleeve 100 and prevent the molten glue from damaging the nozzle assembly.

Eighth embodiment

The nozzle assembly of the eighth embodiment is an improvement of the nozzle assembly of the seventh embodiment. Referring to fig. 1 and 2, in order to facilitate installation of the sealing ring 900, the lower end of the nozzle 200 is further provided with an annular clamping groove, and the upper portion of the inner side surface of the sealing ring 900 is provided with a snap ring which is clamped in the annular clamping groove. Therefore, when the sealing ring 900 is installed, the sealing ring 900 can be firstly sleeved on the lower end of the nozzle 200, the clamping ring is clamped in the annular clamping groove, the water conveying sleeve 100 is sleeved on the lower end of the nozzle 200, and the water conveying sleeve 100 and the nozzle 200 clamp the sealing ring 900 tightly.

Ninth embodiment

The nozzle assembly of the ninth embodiment is an improvement of the nozzle assembly of the first embodiment.

Referring to fig. 1, in order to continuously heat the nozzle 200 and ensure that the melt adhesive in the valve pin hole 240 is in a molten state, a heating member 500 is provided, and the heating member 500 is coated on the outer circumferential surface of the nozzle 200. Thus, the heat generated from the heating member 500 can be uniformly permeated from the circumferential direction of the nozzle 200, so that the melting glue in the needle hole 240 is in a molten state.

By using the nozzle assembly described above, the nozzle 200 can be maintained at a relatively high temperature to ensure that the gum material is in a molten state. Meanwhile, in unit time, the heat received by the gate area from the nozzle 200 is reduced, the temperature of the gate area is not too high, and the phenomenon of delayed solidification of the melt in the gate area is effectively relieved.

In this embodiment, the heating element 500 is a copper sheathed heater comprising a copper sheath and an electric heating tube. The copper sleeve is hollow, the copper sleeve is sleeved outside the nozzle 200, and the lower half part of the copper sleeve is positioned in the second accommodating cavity 350 of the outer sleeve 300. The outer surface of the copper sleeve is provided with a spiral groove, and the electric heating pipe is embedded in the groove. The copper sleeve has good thermal conductivity and can conduct heat to the nozzle 200 well.

In another embodiment, the heating element 500 may be a ceramic heater uniformly coated on the outer surface of the nozzle 200.

Referring to fig. 1, the present invention also relates to a needle valve hot runner system comprising a nozzle assembly according to any of the above, further comprising a manifold 600, a valve needle 700 and a drive means 800. The diverter plate 600 has a flow passage 610 disposed therein, the flow passage 610 communicating with the needle bore 240. Valve pin 700 is inserted into valve pin bore 240. The drive means 800 is capable of driving the valve needle 700 to slide along the valve needle bore 240.

In this embodiment, the driving device 800 is an air cylinder, a cylinder body of the air cylinder is fixed relative to the flow distribution plate 600, and an upper end of the valve needle 700 is fixedly connected with an expansion rod of the air cylinder. After the cylinder is ventilated, the valve needle 700 can be driven to slide up and down along the valve needle hole 240. In another embodiment, the driving device 800 may also be a linear motor, and the linear motor may also drive the valve needle 700 to slide up and down along the valve needle hole 240.

Nozzle 200 comprises tip 210, core 220 and body 230. The upper end of nozzle body 230 is inserted into the groove of flow distribution plate 600, the lower end of nozzle body 230 is provided with an installation groove along the axial direction, the inner surface of the installation groove is provided with an internal thread, the outer circumferential surface of nozzle core 220 is provided with an external thread, and nozzle core 220 is inserted into the installation groove and is in threaded connection with nozzle body 230. Mouth piece 210 is below mouth piece 220, and the upper end of mouth piece 210 also has external screw thread, and the upper end of mouth piece 210 is inserted in the mounting groove and is held against mouth piece 220, and the upper end of mouth piece 210 is still connected with the mounting groove screw thread.

Referring to fig. 3, in order to facilitate the transportation of the nozzle assembly, a lifting screw hole 370 is further formed in the upper end surface of the outer sleeve 300, and after the lifting screw hole 370 is screwed into a lifting ring, the nozzle assembly can be transported by a lifting rope.

Referring to fig. 1, 3, 4, 6 and 7, in order to realize the installation of the nozzle assembly, the needle valve hot runner system further comprises a support ring 400, the support ring 400 is provided with two stepped holes 410 (refer to fig. 1), the outer sleeve 300 is provided with two through holes 360, the water transport sleeve 100 is provided with two threaded holes 126, one stepped hole 410, one through hole 360 and one threaded hole 126 are coaxially arranged, and the other stepped hole 410, the other through hole 360 and the other threaded hole 126 are also coaxially arranged. After passing through the stepped holes 410 and the through holes 360, screws are screwed into the screw holes 126, thereby fixing the support ring 400, the outer sleeve 300, and the water jacket 100 together.

After the nozzle assembly is assembled, the nozzle assembly is placed in a frame groove of the die and is pressed in the frame groove through the template.

Referring to fig. 7 and 10, in order to prevent the cooling water introduced to the outer surface of the water jacket 100 from leaking, a second annular groove 121 is formed at the upper end of the water jacket 100, and a third annular groove 111 is formed at the lower end of the water jacket 100. A second seal ring is disposed in the second annular groove 121 and a third seal ring is disposed in the third annular groove 111. After the nozzle assembly is placed in a frame groove of the mold, the water conveying sleeve 100 and the mold clamp the second sealing ring and the third sealing ring together, and cooling water is prevented from leaking from a gap between the water conveying sleeve 100 and the mold.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention. Furthermore, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.

Claims

1. A nozzle assembly, comprising:

the nozzle is internally provided with a valve needle hole;

the heat insulation assembly comprises an outer sleeve and a water conveying sleeve, the outer sleeve is arranged at the glue outlet end of the nozzle, the water conveying sleeve is arranged outside the outer sleeve, a first heat insulation cavity is formed between the outer sleeve and the water conveying sleeve, and the water conveying sleeve is provided with a cooling water channel.

2. The nozzle assembly of claim 1 wherein an insulating ring is further disposed in said first chamber, an inner annular surface of said insulating ring being connected to said jacket and an outer annular surface of said insulating ring being connected to said water jacket.

3. The nozzle assembly of claim 2 wherein said heat insulating ring is an annular projection formed on the outer surface of said outer sleeve.

4. The nozzle assembly of claim 1 wherein a second insulated chamber is formed between said outer sleeve and said nozzle.

5. The nozzle assembly of claim 1, wherein the water transport sleeve comprises a first water transport sleeve and a second water transport sleeve, the second water transport sleeve is sleeved outside the jacket, the first water transport sleeve is disposed at one end of the second water transport sleeve near the glue outlet end of the nozzle, and the cooling water channel is an annular cavity formed between the first water transport sleeve and the second water transport sleeve.

6. The nozzle assembly of claim 5, wherein the outer surface of the second water jacket is provided with a water inlet and a water outlet, both of which are in communication with the annular cavity.

7. The nozzle assembly of claim 1, wherein the heat insulation assembly further comprises a sealing ring, the sealing ring is arranged on the glue outlet side of the nozzle, the glue outlet of the nozzle is located in an area defined by the sealing ring, and two side surfaces of the sealing ring are respectively abutted against the nozzle and the water conveying sleeve.

8. The nozzle assembly of claim 7 wherein said nozzle has an annular groove and said sealing ring has a snap ring that snaps into said annular groove.

9. A nozzle assembly according to any one of claims 1 to 8, further comprising a heating element, said heating element being coated on an outer circumferential surface of said nozzle.

10. A needle valve hot runner system, comprising the needle valve hot runner system according to any one of claims 1 to 9, further comprising a flow distribution plate, a valve needle and a driving device, wherein a flow passage is provided in the flow distribution plate, the flow passage is communicated with the valve needle hole, the valve needle is inserted in the valve needle hole, and the driving device can drive the valve needle to slide along the valve needle hole.