Heat dissipation structure and heat dissipation method of hot runner nozzle core

Abstract

The heat dissipation structure comprises a glue injection pipe, the bottom of the glue injection pipe is provided with a nozzle core, the nozzle core is inserted into the glue injection pipe, the nozzle core comprises a nozzle core seat and a guide core located below the nozzle core seat, the nozzle core seat is inserted into the glue injection pipe, the glue injection pipe is further provided with a glue injection head, and the glue injection head is inserted into the glue injection pipe. The glue injection head is located below the nozzle core seat and comprises an intersection hole located on the upper portion, the guide core is inserted into the intersection hole, the nozzle core is provided with a third counter bore, the nozzle core seat is provided with two second hole channels, insertion pipes are installed in the second hole channels in an inserted mode and comprise two first pipe bodies, and the third counter bore, the second hole channels and the two first pipe bodies are communicated with each other. The first pipe body penetrates through the glue injection pipe and at least partially extends out of the glue injection pipe. According to the heat dissipation structure and heat dissipation method of the hot runner nozzle core, the heat dissipation function at the sprue gate is added, the pouring temperature of the sprue gate is adjusted in time, and the product forming quality is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of hot runners, and in particular to a heat dissipation structure and a heat dissipation method of a hot runner nozzle. Background Art

[0002] At present, when injecting thick-walled light guides, the molding process is very special because the wall thickness of the product is very thick. Thick-walled light guides need to have very good light transmittance, and there should be no shrinkage problem in the thick wall, and there should be no flow lines in the important light distribution position. Therefore, such products can only be molded by high-pressure and low-speed molding processes. At the same time, thick-walled light guides have important appearance requirements, and there must be no product defects such as yellowing and air lines in the product. During the entire injection molding process, due to the pressure loss of the plastic melt in the pipeline and the resulting temperature increase during the melt transmission process, the melt temperature at the gate is uncontrollable and cannot be adjusted in time, resulting in poor product molding quality and increased scrap rate. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art, provide a heat dissipation structure and heat dissipation method for a hot runner nozzle, increase the heat dissipation function at the pouring gate, timely adjust the pouring temperature of the pouring gate, and improve the product molding quality.

[0004] The invention discloses a heat dissipation structure of a hot runner nozzle core, comprising a glue injection tube, a nozzle core is installed at the bottom of the glue injection tube, the nozzle core is inserted into the glue injection tube, the nozzle core comprises a nozzle core seat and a guide core located below the nozzle core seat, the nozzle core seat is inserted into the glue injection tube, the glue injection tube is also equipped with a glue injection head, the glue injection head is inserted into the glue injection tube, the glue injection head is located below the nozzle core seat, the glue injection head comprises an intersection hole located above, the guide core is inserted into the intersection hole, the nozzle core is provided with a countersunk hole three, the nozzle core seat is provided with two channels two, an insert is inserted and installed in the channel two, the insert comprises two tube bodies one, the countersunk hole three, the channel two, and the two tube bodies one are connected to each other, the tube body one passes through the glue injection tube and at least partially extends out of the glue injection tube.

[0005] Furthermore, the channel two is arranged radially along the mouth core seat, the two channels two are distributed up and down, a plug cover is installed on the top of the countersunk hole three, the bottom of the plug cover is arc-shaped, and the connection between the channel two and the countersunk hole three located above is tangent to the arc of the bottom of the plug cover.

[0006] Furthermore, a pipe sleeve is inserted and installed in the second channel, and the pipe body 1 is inserted into the pipe sleeve, and the pipe body 1 can move axially along the pipe sleeve.

[0007] Furthermore, the insert is installed with a catheter, which passes through one of the tube bodies 1. The catheter includes port 1 and port 2. Port 1 is located at the bottom of countersunk hole 3, and port 2 passes through the insert and is located radially outside the injection tube.

[0008] Furthermore, the nozzle core seat is provided with a channel 1, which axially passes through the nozzle core seat, the injection tube is provided with a countersunk hole 1 and a countersunk hole 2, the countersunk hole 1 is located above the countersunk hole 2, the nozzle core seat is inserted into the countersunk hole 1, and the bottom of the channel 1 is connected with the countersunk hole 2.

[0009] Furthermore, the cannula is provided with an inlet, the inlet is equipped with a second valve, the cannula is also provided with an outlet, the cannula is equipped with a drainage box, and the drainage box is connected to the outlet.

[0010] Furthermore, a sealing cover is installed on the pipe sleeve located at the bottom. The sealing cover is located on a side close to the countersunk hole three. The sealing cover is provided with a through hole, and the through hole axially penetrates the sealing cover.

[0011] The present invention also discloses a heat dissipation method for a hot runner nozzle core, using a heat dissipation structure of the hot runner nozzle core, including the following heat dissipation method:

[0012] ① Cooling water is injected into the insert tube, and the cooling water flows from the tube body 1 into the sink hole 3. The cooling water is heated and boils and vaporizes, so that the outer wall of the guide core and the plastic melt in the intersection hole generate heat exchange;

[0013] ② After the cooling water is heated, boiled and vaporized, the water vapor enters the insert pipe from the upper sleeve to form heat exchange with the outside world and then liquefies, and flows back to the sink hole 3 from the pipe body 1 and the through hole at the bottom, forming a cooling cycle.

[0014] Furthermore, the cooling water temperature is 90°C-95°C.

[0015] Beneficial effects of the present invention:

[0016] 1. The insert is installed through the nozzle core, and the insert is extended out of the injection tube, so that the plastic melt in the intersection hole can exchange heat with the outside world, and the melt at the gate can be quickly adjusted, which solves the problem of temperature rise caused by high pressure loss during the transmission of the plastic melt, so that the melt at the pouring port (i.e. the injection head) can ensure the required pouring temperature, thereby improving the control of the molding quality of plastic products.

[0017] 2. The heat exchange rate between the water vapor in the insert and the outside world can be controlled by moving the insert to increase the length of the insert extending out of the injection tube. Since the temperature of the injected cooling water is controlled at 90℃-95℃, it can prevent the injection molding melt from being suddenly cooled due to excessive temperature difference and causing product quality problems (yellowing, gas marks and other product defects). In addition, the cooling water can be vaporized immediately. During vaporization, the heat is evenly transferred to the three-hole wall of the countersunk hole that is not in contact with the cooling water, making the heat exchange of the plastic melt in the intersection hole smoother, so as to improve the subsequent product molding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a cross-sectional view of an embodiment;

[0019] Figure 2 for Figure 1 The enlarged view of point A in the middle;

[0020] Figure 3 for Figure 2 The enlarged view of point B in the middle;

[0021] Figure 4 for Figure 2 Sectional view along the MM direction.

[0022] Figure numerals: injection tube 1, counterbore 11, counterbore 2 12, nozzle core 2, nozzle core seat 21, channel 1 211, channel 2 212, guide core 22, counterbore 3 23, injection head 3, flow channel hole 31, intersection hole 311, plugging cover 4, insert tube 5, tube body 1 51, inlet 52, outlet 53, conduit 6, port 1 61, port 2 62, pipe sleeve 7, sealing cover 71, through hole 711, drainage box 8, plug rod 81, boss 811, unloading port 82, valve 1 83, valve 2 9. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in this embodiment to clearly and completely describe the technical solution in this embodiment. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] like Figure 1 As shown, a heat dissipation structure of a hot runner nozzle core includes a glue injection tube 1, which is axially arranged in the vertical direction. A diverter plate of the hot runner is installed on the upper end of the glue injection tube 1. A countersunk hole 11 and a countersunk hole 12 are arranged at the bottom of the glue injection tube 1. The countersunk hole 11 is located above the countersunk hole 12. A glue injection head 3 is installed at the bottom of the glue injection tube 1. The upper end of the glue injection head 3 is inserted into the countersunk hole 12 and sealed and fixed. An injection casting channel is axially arranged in the glue injection tube 1. The injection melt entering the runner plate flows from top to bottom along the axial direction of the glue injection tube 1 and is injected into the mold cavity through the glue injection head 3.

[0025] like Figure 2 As shown, a nozzle core 2 is also installed at the bottom of the glue injection tube 1. The nozzle core 2 is inserted into the glue injection tube 1, and part of the nozzle core 2 is located above the glue injection head 3. Specifically, the nozzle core 2 includes a nozzle core seat 21 and a guide core 22 located below the nozzle core seat 21. The nozzle core seat 21 is inserted into the counterbore 11, and the outer peripheral wall of the nozzle core seat 21 fits with the hole wall of the counterbore 11. The upper end of the nozzle core seat 21 abuts against the upper wall of the counterbore 11, and the lower end of the nozzle core seat 21 abuts against the upper end of the glue injection head 3. The glue injection head 3 is provided with a flow channel hole 31, and the flow channel hole 31 passes through the glue injection head 3 from top to bottom. The flow channel hole 31 includes a junction hole 311 located at the upper end, and the junction hole 311 is located below the nozzle core seat 21. The guide core 22 is inserted into the junction hole 311. Combined with Figure 4The nozzle core seat 21 is provided with a channel 211, the channel 211 axially penetrates the nozzle core seat 21, and the bottom of the channel 211 is connected to the countersunk hole 2 12.

[0026] like Figure 2 As shown, the mouth core 2 is provided with a countersunk hole three 23, which extends downward along the top surface of the mouth core 2 to the bottom of the guide core 22, and the bottom of the countersunk hole three 23 does not penetrate the bottom of the guide core 22. A plugging cover 4 is installed on the top of the countersunk hole three 23, and the plugging cover 4 closes the top outlet of the countersunk hole three 23.

[0027] like Figure 2 As shown, the nozzle core seat 21 is provided with two second channels 212, which are arranged radially along the nozzle core seat 21, and the two second channels 212 are distributed up and down, and the injection tube 1 is provided with a channel coaxial with the second channel 212, and a pipe sleeve 7 is inserted and installed in the second channel 212, and a plug 5 is inserted and inserted in the pipe sleeve 7 in a sliding connection, and the left end of the plug 5 extends out of the injection tube 1, and the plug 5 can move axially along the inner wall of the pipe sleeve 7. Specifically, combined with Figure 3 The insert tube 5 includes two tube bodies 51, the tube body 51 is inserted into the inner wall of the tube sleeve 7 and can move axially along the tube sleeve 7, and the tube body 51 passes through the injection tube 1 and at least partially extends out of the injection tube 1.

[0028] An inlet 52 is provided at the upper end of the insert tube 5 extending out of the left end of the injection tube 1, and a valve 2 9 is installed at the inlet 52. An outlet 53 is provided at the lower end of the insert tube 5 extending out of the left end of the injection tube 1. A drainage box 8 is installed at the insert tube 5, and a discharge port 82 is provided at the discharge port 82. A valve 1 83 is installed at the discharge port 82. The inlet 52 can be passed with cooling water, and the cooling water can be discharged from the discharge port 82 of the drainage box 8 through the outlet 53. A plug rod 81 is threadedly connected to the bottom surface of the drainage box 8, and the plug rod 81 is provided with a boss 811. The boss 811 is located below the outlet 53, and the outer diameter of the boss 811 is larger than the diameter of the outlet 53. The boss 811 moves upward to abut against the insert tube 5 to close the outlet 53, and the boss 811 moves downward to open the outlet 53.

[0029] like Figure 2 As shown, the countersunk hole 3 23, the channel 212, and the two tube bodies 51 are interconnected. To be precise, the countersunk hole 3 23, the pipe sleeve 7, and the two tube bodies 51 are connected.

[0030] like Figure 2 , Figure 3As shown, the bottom of the plugging cover 4 is arc-shaped, and the connection between the second channel 212 and the third countersunk hole 23 located above is tangent to the arc of the bottom of the plugging cover 4. Cooling water is injected through the inlet 52, and the maximum injection amount of cooling water does not exceed half of the depth of the third countersunk hole 23. The temperature of the injected cooling water is controlled at 90℃-95℃. The cooling water flows into the third countersunk hole 23. Since the temperature of the injection molding melt is between 140℃-240℃, the cooling water in the third countersunk hole 23 is heated and quickly boils and vaporizes. The water vapor enters the insert 5 and circulates. After heat exchange with the outside through the insert 5, it forms a liquid and flows back to the third countersunk hole 23. The rate of heat exchange between the water vapor in the insert tube 5 and the outside is controlled by moving the insert tube 5 to increase the length of the insert tube 5 extending out of the injection tube 1. Since the temperature of the injected cooling water is controlled at 90°C-95°C, the injection molding melt is prevented from being suddenly cooled due to excessive temperature difference, thereby causing product quality problems (yellowing, gas marks and other product defects). In addition, the cooling water can be vaporized immediately, and the heat is evenly transferred to the wall of the countersunk hole 3 23 that is not in contact with the cooling water during vaporization, so that the heat exchange of the plastic melt in the intersection hole 311 is smoother, thereby improving the subsequent product molding quality.

[0031] like Figure 3 As shown, the pipe sleeve 7 located at the bottom is installed with a cover 71, and the cover 71 is located on the side close to the countersunk hole three 23. A through hole 711 is provided at the lower end of the cover 71, and the hole 711 axially penetrates the cover 71, so that the inlet cross-section of the pipe sleeve 7 located at the bottom is reduced, and most of the water vapor enters the pipe sleeve 7 located at the top along the curved surface at the bottom of the plugging cover 4, and then flows along the tube body 51 located at the top, forms heat exchange with the outside world, and then liquefies, and flows back to the countersunk hole three 23 from the tube body 51 located at the bottom and the through hole 711.

[0032] like Figure 2 , Figure 3 As shown, the insert tube 5 is installed with a conduit 6, which passes through one of the tube bodies 51. The conduit 6 includes a port 1 61 and a port 2 62. The port 1 61 is located at the bottom of the countersunk hole 3 23, and the port 2 62 passes through the insert tube 5 and is located radially outside the injection tube 1. By setting the conduit 6, the water in the countersunk hole 3 23 can be pumped out, so that the internal plastic melt can be cooled only when needed.

[0033] A heat dissipation method for a hot runner nozzle core includes the heat dissipation structure of the hot runner nozzle core. The specific heat dissipation method is as follows:

[0034] ① Such as Figure 2 , Figure 3 As shown, valve 2 9 is opened and cooling water at 90°C-95°C is injected into the insert tube 5. The cooling water flows from the tube body 1 51 into the sink hole 3 23. The cooling water is heated and boils and vaporizes, so that the outer wall of the guide core 22 and the plastic melt in the intersection hole 311 generate heat exchange, causing the plastic melt to cool down.

[0035] ② After the cooling water is heated and boiled, the water vapor enters the insert pipe 5 from the upper pipe sleeve 7 to form heat exchange with the outside world and then liquefies, and flows back to the sink hole 3 23 from the lower pipe body 51 and the through hole 711, forming a cooling cycle.

[0036] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A heat dissipation structure of a hot runner nozzle, characterized in that: The invention comprises a glue injection tube (1), a nozzle core (2) is installed at the bottom of the glue injection tube (1), the nozzle core (2) is inserted into the glue injection tube (1), the nozzle core (2) comprises a nozzle core seat (21) and a guide core (22) located below the nozzle core seat (21), the nozzle core seat (21) is inserted into the glue injection tube (1), the glue injection tube (1) is also installed with a glue injection head (3), the glue injection head (3) is inserted into the glue injection tube (1), the glue injection head (3) is located below the nozzle core seat (21), and the glue injection head (3) comprises a nozzle core seat (21) located above the nozzle core seat (21). The guide core (22) is inserted into the intersection hole (311), the nozzle core (2) is provided with a countersunk hole three (23), the nozzle core seat (21) is provided with two channel twos (212), a plug (5) is inserted and installed in the channel twos (212), the plug (5) comprises two tube bodies one (51), the countersunk hole three (23), the channel twos (212), and the two tube bodies one (51) are connected to each other, and the tube body one (51) passes through the injection tube (1) and at least partially extends out of the injection tube (1).

2. The heat dissipation structure of a hot runner nozzle according to claim 1, characterized in that: The second channel (212) is radially arranged along the nozzle core seat (21), and the two second channels (212) are distributed up and down. A plugging cover (4) is installed on the top of the third countersunk hole (23), and the bottom of the plugging cover (4) is arc-shaped. The connection between the second channel (212) and the third countersunk hole (23) located above is tangent to the arc of the bottom of the plugging cover (4).

3. The heat dissipation structure of a hot runner nozzle according to claim 1, characterized in that: A pipe sleeve (7) is inserted and installed in the second hole (212), and the first pipe body (51) is inserted into the pipe sleeve (7). The first pipe body (51) can move axially along the pipe sleeve (7).

4. The heat dissipation structure of a hot runner nozzle according to claim 1, characterized in that: The insert tube (5) is installed with a catheter (6), and the catheter (6) passes through one of the tube bodies (51). The catheter (6) includes a port (61) and a port (62). The port (61) is located at the bottom of the counterbore (23), and the port (62) passes through the insert tube (5) and is located radially outside the injection tube (1).

5. The heat dissipation structure of a hot runner nozzle according to claim 1, characterized in that: The nozzle core seat (21) is provided with a channel 1 (211), and the channel 1 (211) axially penetrates the nozzle core seat (21); the injection tube (1) is provided with a countersunk hole 1 (11) and a countersunk hole 2 (12); the countersunk hole 1 (11) is located above the countersunk hole 2 (12); the nozzle core seat (21) is inserted into the countersunk hole 1 (11), and the bottom of the channel 1 (211) is connected to the countersunk hole 2 (12).

6. The heat dissipation structure of a hot runner nozzle according to claim 1, characterized in that: The cannula (5) is provided with an inlet (52), and the inlet (52) is equipped with a valve 2 (9). The cannula (5) is also provided with an outlet (53), and the cannula (5) is equipped with a drainage box (8), and the drainage box (8) is connected to the outlet (53).

7. The heat dissipation structure of a hot runner nozzle according to claim 3, characterized in that: The pipe sleeve (7) located at the bottom is installed with a cover (71), and the cover (71) is located on a side close to the countersunk hole three (23). The cover (71) is provided with a through hole (711), and the through hole (711) axially penetrates the cover (71).

8. A heat dissipation method for a hot runner nozzle, using the heat dissipation structure of a hot runner nozzle according to any one of claims 1 to 7, characterized in that: The heat dissipation methods include the following: ① Cooling water is injected into the insert tube (5), and the cooling water flows from the tube body (51) into the sink hole (23). The cooling water is heated and boils and vaporizes, so that the outer wall of the guide core (22) and the plastic melt in the intersection hole (311) generate heat exchange; ② After the cooling water is heated and boiled, the water vapor enters the insert pipe (5) from the upper pipe sleeve (7) to form heat exchange with the outside world and then liquefies, and flows back to the sink hole three (23) from the lower pipe body one (51) and the through hole (711), forming a cooling cycle.

9. The heat dissipation method of a hot runner nozzle according to claim 8, characterized in that: The cooling water temperature is 90°C-95°C.

Images