A hot runner assembly in an injection molding machine

Abstract

The application discloses a hot runner assembly in an injection molding machine, which comprises a support and a runner body, the runner body further comprises first, second, third and fourth runner bodies connected in sequence, and a nozzle arranged on the fourth runner body; a valve needle linkage connecting rod mechanism is arranged on the runner body, which comprises a hinged mounting seat, linkage rods, first and second cross rods, and first, second and third connecting rods; a reset spring is arranged between the hinged mounting seat and the second runner body, a first valve needle and a first cross rod setting long hole are arranged at the corresponding end of the third runner body, the first cross rod is arranged in the first cross rod setting long hole and is connected with the first valve needle perpendicularly, a second cross rod setting long hole is arranged on the fourth runner body, the second cross rod is arranged in the second cross rod setting long hole, and the two ends of the second cross rod are connected with the middle parts of corresponding second connecting rods respectively, and the second cross rod is connected with a second valve needle arranged in the nozzle perpendicularly. The hot runner assembly can be applied to various injection molding machines.

Description

Technical Field

[0001] This invention relates to injection molding machines, and more specifically to a hot runner assembly in an injection molding machine. Background Technology

[0002] Currently, the valve control device at the outlet of the hot runner assembly in injection molding machines requires external force to close. In actual use, because the valve control device cannot sense changes in the material in the runner, it cannot close the outlet of the hot runner assembly at the optimal time for material changes, resulting in material leakage. Moreover, the leaked material can clog the outlet, further affecting the normal operation of the valve control device. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a hot runner assembly in an injection molding machine that can close the outlet without external force.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: a hot runner assembly in an injection molding machine, comprising: a support, a runner body, and a heater disposed on the runner body. The specific structure of the runner body includes: a first runner body passing through the support, a second runner body connected to the first runner body, a third runner body connected to the second runner body, and a fourth runner body connected to the third runner body, and a nozzle disposed on the fourth runner body; a valve needle linkage linkage mechanism is provided on the runner body, the valve needle linkage linkage mechanism comprising: a pair of linkage rods disposed on the end of the second runner body near the first runner body via a hinged mounting seat, a first link, a second link, and a third link corresponding to the linkage rods, and a mechanism for movably hinged to the pair of linkage rods. The first crossbar and the corresponding ends of the second crossbar of the third connecting rod are movably hinged. One end of the linkage rod is movably hinged to the hinge mounting base, and the other end of the linkage rod is movably hinged to the corresponding end of the first connecting rod. The other end of the first connecting rod is movably hinged to the corresponding end of the second connecting rod, and the other end of the second connecting rod is movably hinged to the other end of the third connecting rod. An adjusting thread section is provided on the other end of the second flow channel body, and an adjusting nut is provided on the adjusting thread section. A return spring is sleeved between the hinge mounting base and the adjusting nut in the second flow channel body. A central flow channel is opened in the first flow channel body and the second flow channel body, and an annular valve needle seat is provided on the inner wall of the central flow channel of the second flow channel body near the end of the third flow channel body. The third flow channel body has a first valve needle mounting hole at one end near the second flow channel body. A first valve needle is movably inserted through the first valve needle mounting hole. A valve seat with a diameter larger than the inner hole of the annular valve needle seat is provided on the corresponding end of the first valve needle. A valve plug that mates with the inner hole of the annular valve needle seat is provided on the valve seat. The third flow channel body also has a first crossbar mounting elongated hole that is perpendicular to the first valve needle mounting hole and penetrates the third flow channel body. The first crossbar is movably inserted through the first crossbar mounting elongated hole, and the corresponding end of the first valve needle is connected to the middle of the first crossbar. The other end of the third flow channel body has a central flow channel. Several central flow channels connecting the second and third flow channels are formed around the valve needle mounting hole at the corresponding end of the third flow channel body. The eccentric flow channel of the flow channel includes a hinged support and a transversely penetrating second crossbar mounting hole arranged sequentially along the discharge direction on the fourth flow channel body. The second crossbar is movably inserted into the second crossbar mounting hole. The middle of a pair of second connecting rods is movably hinged to the hinged support. A second valve needle mounting hole communicating with the second crossbar mounting hole is also opened in the corresponding end of the fourth flow channel body. A second valve needle is movably inserted into the second valve needle mounting hole. The corresponding end of the second valve needle is connected to the second crossbar. At least one eccentric flow channel connecting the nozzle and the central flow channel in the third flow channel body is opened circumferentially in the fourth flow channel body. A plunger that cooperates with the injection hole in the nozzle is provided on the other end of the second valve needle, forming a limiting step at the corresponding end of the second valve rod.

[0005] As a preferred embodiment, in the hot runner assembly of the injection molding machine, the fourth runner body is provided with a gradually tapering annular guide boss at one end near the injection hole.

[0006] As a preferred embodiment, in the hot runner assembly of the injection molding machine, the side of the annular guide boss is an arc-shaped curved surface.

[0007] As a preferred embodiment, in the hot runner assembly of the injection molding machine, the plunger top of the second valve needle is provided with a tapered guide head.

[0008] As a preferred embodiment, in the hot runner assembly of the injection molding machine, the limiting step is conical.

[0009] As a preferred embodiment, in the hot runner assembly of the injection molding machine, the top of the nozzle is also tapered, with a taper greater than that of the limiting step.

[0010] As a preferred embodiment, in the hot runner assembly of the injection molding machine, the corresponding end of the second runner is inserted into the first runner, the corresponding end of the third runner is inserted into the second runner, the corresponding end of the fourth runner is inserted into the third runner, and the corresponding end of the fourth runner is inserted into the nozzle.

[0011] The beneficial effects of this invention are as follows: This invention utilizes the fluid's own pressure within the flow channel to sequentially drive the first valve needle, which in turn drives the first crossbar. The first crossbar then drives the linkage rod, which in turn drives the second crossbar via first, second, and third connecting rods. Finally, the second crossbar drives the second valve needle to open the injection orifice in the nozzle. Once the fluid pressure disappears, the second valve needle automatically closes the injection orifice in the nozzle at the optimal time under the action of the return spring, effectively preventing material leakage and making the valve control device, composed of the first valve needle, the second valve needle, and the valve needle linkage mechanism, more reliable in operation. Furthermore, adjusting the spring force of the return spring by adjusting the nut further improves the reliability of the valve control device in actual use. Attached Figure Description

[0012] Figure 1 This is a three-dimensional structural diagram of the hot runner assembly described in this invention.

[0013] Figure 2 This is a front view of the nozzle structure of the hot runner assembly described in this invention.

[0014] Figure 3 yes Figure 2 A structural schematic diagram in the AA section direction.

[0015] Figure 4 yes Figure 3A structural schematic diagram of the BB cross-section.

[0016] Figure 5 yes Figure 4 A schematic diagram of the structure with the central perforation hole in the closed state.

[0017] Figures 1 to 5 The reference numerals in the attached drawings are as follows: 1. Support; 21. First flow channel body; 210. First central flow channel; 218. First heater; 22. Second flow channel body; 220. Second central flow channel; 221. Annular valve needle seat; 23. Third flow channel body; 230. Third central flow channel; 231. First crossbar mounting elongated hole; 233. First eccentric flow channel; 238. Second heater; 24. Fourth flow channel body; 240. Hinge support; 241. Second crossbar mounting elongated hole. 243. Hole, second eccentric flow channel, 25. Nozzle, 251. Perforation hole, 26. First valve needle, 261. Valve seat, 262. Valve plug, 27. Second valve needle, 271. Plunger, 272. Annular guide boss, 273. Limiting step, 30. Hinge mounting seat, 31. Linkage rod, 32. First crossbar, 33. Second crossbar, 34. Return spring, 35. Adjusting nut, 36. First connecting rod, 37. Second connecting rod, 38. Third connecting rod. Detailed Implementation

[0018] The following is in conjunction with the appendix Figures 1 to 5 The present invention describes in detail the specific implementation scheme of the hot runner assembly in the injection molding machine.

[0019] like Figure 1 , Figure 2 and Figure 4 As shown, the hot runner assembly in the injection molding machine of the present invention includes: a support 1, a runner body, and a valve needle linkage mechanism disposed on the runner body. The runner body includes: one end ( Figure 4 The first flow channel 21 (left end) is inserted into the support 1, the second flow channel 22 (left end) is inserted into the first flow channel 21, the third flow channel 23 (left end) is inserted into the second flow channel 22, the fourth flow channel 24 (left end) is inserted into the third flow channel 23, and the nozzle 25 is sleeved on the right end of the fourth flow channel 24 (the connection structure between them is conventional technology in the art and will not be described in detail here); the first flow channel 21 is provided with a first heater 218, the third flow channel 23 is provided with a second heater 238, and the valve needle linkage linkage mechanism includes: a first crossbar 32, a second crossbar 33, a pair of first connecting rods 36, a pair of second connecting rods 37, a pair of third connecting rods 38, and a nozzle 25 disposed at the end of the second flow channel 22 near the first flow channel 21. Figure 4 The hinged mounting base 30 on the left end and one end of it (in the middle) Figure 4The left end of the first crossbar 32 is symmetrically hinged to a pair of linkage rods 31 on both sides of the hinge mounting base 30. The two ends of the first crossbar 32 are respectively hinged to the middle of the corresponding linkage rod 31. The other end of the linkage rod 31 is hinged to one end of the corresponding first connecting rod 36. One end of the first connecting rod 36 is hinged to one end of the second connecting rod 37. One end of the second connecting rod 37 is hinged to one end of the third connecting rod 38. The other end of the third connecting rod 38 is hinged to the corresponding end of the second crossbar 33. The second flow channel body 22 has an adjusting threaded section at its other end, and an adjusting screw is provided on the adjusting threaded section. Mother 35, the second flow channel body 22 has a return spring 34 sleeved between the hinge mounting base 30 and the adjusting nut 35, the first flow channel body 21 has a first central flow channel 210, the second flow channel body 22 has a second central flow channel 220 connected to the first central flow channel 210, the inner wall of the second central flow channel 220 of the second flow channel body 22 has an annular valve needle seat 221 at one end near the third flow channel body 23, the third flow channel body 23 has a first valve needle mounting hole at one end near the second flow channel body 22, the first valve needle 26 is movably inserted in the first valve needle mounting hole, the corresponding end of the first valve needle 26 ( Figure 4 A valve seat 261 with a diameter larger than the inner hole of the annular valve needle seat 221 is provided on the left end of the valve seat 261. A valve plug 262 that mates with the inner hole of the annular valve needle seat 221 is provided on the valve seat 261. The third flow channel body 23 is also provided with a first crossbar mounting elongated hole 231 that is perpendicular to and passes through the first valve needle mounting hole. The first crossbar 32 is movably inserted into the first crossbar mounting elongated hole 231. The corresponding end of the first valve needle 26 ( Figure 4 The right end of the third flow channel 23 is connected to the middle of the first crossbar 32; the other end of the third flow channel 23 is connected to the middle of the first crossbar 32. Figure 4 A third central flow channel 230 is provided at the right end of the middle section, and the corresponding end of the third flow channel body 23 ( Figure 4 The left end of the valve needle mounting hole has several first eccentric channels 233 that connect the second central channel 220 and the third central channel 230 (see the left end of the valve needle mounting hole). Figure 3 As shown), the fourth flow channel 24 is provided with a hinged support 240 and a transverse through-hole 241 for mounting a second crossbar along the discharge direction. The second crossbar 33 is movably inserted into the second crossbar through-hole 241. The middle of a pair of second connecting rods 37 is movably hinged to the hinged support 240. The corresponding ends of the fourth flow channel 24 ( Figure 4 The right end of the middle section also has a second valve needle mounting hole that communicates with the elongated hole 241 for mounting the second crossbar. A second valve needle 27 is movably inserted into the second valve needle mounting hole, and the corresponding end of the second valve needle 27 ( Figure 4The left end of the second valve needle 27 is connected to the second crossbar 33. The fourth flow channel body 24 has at least one second eccentric flow channel 243 circumferentially arranged, connecting the nozzle 25 and the third flow channel body 23 to the third central flow channel 23. The other end of the second valve needle 27 ( Figure 4 A plunger 271 is provided on the right end of the nozzle 25 to cooperate with the injection hole 251 in the nozzle 25. A tapered guide head is provided on the top of the plunger 271 of the second valve needle 27. Figure 4 A limiting step 273 is formed at the right end of the nozzle 25. The limiting step 273 is conical, and the top of the nozzle 25 is also conical, with a greater taper than that of the limiting step 273. The fourth flow channel 24 has a limiting step 273 at one end near the injection hole 251. Figure 4 The right end of the middle section is provided with a gradually decreasing annular guide protrusion 272, the side of which is an arc-shaped curved surface.

[0020] The working principle of this invention is as follows: Molten plastic (material) enters the second central flow channel 220 through the first central flow channel 210, pushing the valve plug 262 of the first valve needle 26 out of the inner hole of the annular valve needle seat 221, causing the first valve needle 26 to move to the right. During the rightward movement of the first valve needle 26, the first crossbar 32 drives the linkage rod 31 to move to the right. The linkage rod 31, through the first connecting rod 36, the second connecting rod 37 and the third connecting rod 38, drives the second crossbar 33 to move to the left. The second crossbar 33 drives the second valve needle 27 to move to the left, opening the injection hole 251 of the nozzle 25. In this way, the material flows along the first central flow channel 210, the second central flow channel 220, the first eccentric flow channel 233, the third central flow channel 230 and the second eccentric flow channel 243 to the nozzle 25 and flows out from the injection hole 251 of the nozzle 25. When the material injection stops, the pressure in the flow channel decreases, and the first valve needle 26 returns to its original position under the action of the return spring 34. That is, the valve plug 262 on its valve seat 261 inserts into the inner hole of the annular valve needle seat 221. At the same time, the plunger 271 on the second valve needle 27 also inserts into the injection hole 251 of the nozzle 25 (see...). Figure 5 (As shown).

[0021] In summary, these are merely preferred embodiments of the present invention and are not intended to limit the scope of the invention. All equivalent variations and modifications made to the shape, structure, features, and spirit described in the claims of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A hot runner assembly for an injection molding machine, comprising: A support, a flow channel body, and a heater disposed on the flow channel body, characterized in that the specific structure of the flow channel body includes: a first flow channel body passing through the support, a second flow channel body connected to the first flow channel body, a third flow channel body connected to the second flow channel body, and a fourth flow channel body connected to the third flow channel body, and a nozzle disposed on the fourth flow channel body; the flow channel body is provided with a valve needle linkage linkage mechanism, the valve needle linkage linkage mechanism including: a pair of linkage rods disposed on the end of the second flow channel body near the first flow channel body via a hinged mounting seat, a first link, a second link, and a third link corresponding to the linkage rods, and a first crossbar movably hinged to the pair of linkage rods and a second crossbar movably hinged to the corresponding ends of the pair of third links. The linkage rod has one end hinged to a hinge mounting base, and the other end hinged to the corresponding end of the first connecting rod. The other end of the first connecting rod is hinged to the corresponding end of the second connecting rod, and the other end of the second connecting rod is hinged to the other end of the third connecting rod. An adjusting thread section with an adjusting nut is provided on the other end of the second flow channel body. A return spring is fitted between the hinge mounting base and the adjusting nut in the second flow channel body. A central flow channel is formed in both the first and second flow channels. An annular valve needle seat is provided on the inner wall of the central flow channel of the second flow channel body near the end of the third flow channel body. The third flow channel body is located near the end of the second flow channel body. One end of the third flow channel body has a first valve needle mounting hole, through which a first valve needle is movably inserted. A valve seat with a diameter larger than the inner hole of the annular valve needle seat is provided on the corresponding end of the first valve needle. A valve plug that mates with the inner hole of the annular valve needle seat is provided on the valve seat. The third flow channel body also has a first crossbar mounting elongated hole perpendicular to and penetrating the first valve needle mounting hole. The first crossbar is movably inserted into the first crossbar mounting elongated hole, and the corresponding end of the first valve needle is connected to the middle of the first crossbar. The other end of the third flow channel body has a central flow channel. Around the valve needle mounting hole at the corresponding end of the third flow channel body are several eccentric flow channels connecting the central flow channels of the second and third flow channels. The fourth flow channel body is provided with a hinged support and a transversely penetrating second crossbar mounting hole along the discharge direction. The second crossbar is movably inserted into the second crossbar mounting hole. The middle part of a pair of second connecting rods is movably hinged to the hinged support. A second valve needle mounting hole communicating with the second crossbar mounting hole is also opened in the corresponding end of the fourth flow channel body. A second valve needle is movably inserted into the second valve needle mounting hole. The corresponding end of the second valve needle is connected to the second crossbar. At least one eccentric flow channel communicating with the nozzle and the central flow channel in the third flow channel body is opened in the circumferential direction in the fourth flow channel body. A plunger that cooperates with the injection hole in the nozzle is provided on the other end of the second valve needle, forming a limiting step at the corresponding end of the second valve rod.

2. The hot runner assembly in an injection molding machine according to claim 1, characterized in that: The fourth flow channel body is provided with a gradually tapering annular guide protrusion at one end near the perforation hole.

3. A hot runner assembly in an injection molding machine according to claim 2, characterized in that: The side of the annular guide boss is an arc-shaped curved surface.

4. A hot runner assembly in an injection molding machine according to claim 1, characterized in that: The plunger of the second valve needle is provided with a tapered guide head.

5. A hot runner assembly in an injection molding machine according to claim 1, characterized in that: The limiting step is conical.

6. A hot runner assembly in an injection molding machine according to claim 5, characterized in that: The top of the nozzle is conical, and its taper is greater than that of the limiting step.

7. A hot runner assembly in an injection molding machine according to any one of claims 1 to 6, characterized in that: The corresponding end of the second flow channel is inserted into the first flow channel, the corresponding end of the third flow channel is inserted into the second flow channel, the corresponding end of the fourth flow channel is inserted into the third flow channel, and the corresponding end of the fourth flow channel is inserted into the nozzle.

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