A molding die for improving the injection molding quality of fan-shaped chips

Abstract

The present invention relates to a forming mold for improving the injection molding quality of a fan-shaped chip, which includes a mold assembly mainly composed of a front mold and a rear mold. The front mold and the rear mold are connected by a guiding mechanism; a rear mold core is connected to the top of the rear mold, and a fan-shaped groove is vertically opened downward at the top of the rear mold core. An injection molding runner is provided at an outer position of the arc of the fan-shaped groove at the top of the rear mold core. The present invention relates to the technical field of molds. For the forming mold for improving the injection molding quality of a fan-shaped chip, by providing an injection molding runner at the top of the rear mold core and arranging at least two gates in the injection molding runner, multiple gates can be used for simultaneous injection molding to effectively reduce the injection pressure and avoid the generation of internal stress in the plastic part. By providing an exhaust groove at the top of the rear mold core, the exhaust efficiency during injection molding can be ensured, and the generation of vacuum bubbles in the plastic part due to poor exhaust effect can be avoided, further improving the quality of the plastic part of the chemiluminescence centrifugal disc five-item inspection chip.

Description

Technical Field

[0001] The present invention relates to the technical field of molds, and more particularly to a molding mold for improving the injection molding quality of a fan-shaped chip. Background Art

[0002] The chemiluminescence centrifugal disk five - joint inspection chip plastic part is a microfluidic technology product for chemiluminescence immunoassay. According to relevant information, the design of this chip aims to improve the detection efficiency and accuracy, especially in the scenario of multiple detections.

[0003] In the prior art, the chemiluminescence centrifugal disk five - joint inspection chip plastic part is fan - shaped, with many slots distributed inside the plastic part, and the bottoms of the slots are all right - angled, resulting in stress concentration problems during the injection molding of the plastic part. The wall thickness of the chip body of the plastic part is 1.8 mm, and the wall thickness at the slot is 1.0 mm. The difference in wall thickness of the plastic part is too large, and sink marks are likely to appear. Due to the structural limitations of the plastic part, these problems cannot be improved by modifying the plastic part, which affects the performance of the chemiluminescence centrifugal disk five - joint inspection chip plastic part. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a molding mold for improving the injection molding quality of a fan - shaped chip, so as to solve the technical problems mentioned in the foregoing background art.

[0005] The foregoing technical object of the present invention is achieved by the following technical solutions:

[0006] A molding mold for improving the injection molding quality of a fan - shaped chip, including a mold assembly. The mold assembly is mainly composed of a front mold and a rear mold, and the front mold and the rear mold are connected by a guiding mechanism;

[0007] A rear mold core, which is connected to the top of the rear mold. A fan - shaped groove is vertically opened downward at the top of the rear mold core. An injection molding runner is opened at the outer position of the arc of the fan - shaped groove at the top of the rear mold core. At least two gates for injecting into the fan - shaped groove are spaced along the length direction of the injection molding runner. An overflow groove is opened at the side of the fan - shaped groove away from the injection molding runner at the top of the rear mold core. An exhaust groove communicating with the fan - shaped groove is opened at the outer position of the straight - side of the fan - shaped groove at the top of the rear mold core;

[0008] A mold core, which is fixedly connected inside the fan - shaped groove. A plurality of through - grooves are vertically opened downward at the top of the mold core, and inserts are arranged inside the through - grooves.

[0009] Furthermore, the injection molding runner is arc - shaped, and the gates at both ends of the injection molding runner communicate with the position of the arc - side of the fan - shaped groove close to the straight - side.

[0010] Furthermore, both ends of the overflow groove are respectively communicated with two straight-side portions of the sector-shaped groove, and the overflow port of the overflow groove is arranged at the position where the molten glue converges on the straight-side portion of the sector-shaped groove.

[0011] Furthermore, an air channel for exhausting air is formed in the outer wall of the mold core, and a shallow air exhaust port one is formed through the top of the air channel upward. When the mold core is installed in the sector-shaped groove, a micro-gap one for exhausting air is reserved between the outer wall of the mold core and the inner wall of the sector-shaped groove.

[0012] Furthermore, a shallow air exhaust port two is formed in the outer wall of the insert. When the insert is inserted into the through groove, a micro-gap two for exhausting air is reserved between the outer wall of the insert and the inner wall of the through groove.

[0013] Furthermore, a through hole is formed through the top of the insert downward, and a thimble is slidably arranged in the through hole. A shallow air exhaust port three is processed on the outer wall of the thimble. When the thimble is inserted into the through hole, a micro-gap three for air flow is reserved between the outer wall of the thimble and the inner wall of the through hole.

[0014] Furthermore, a cooling water channel is formed in the rear mold core, and the cooling water channel surrounds the outside of the sector-shaped groove.

[0015] In summary, the present invention includes at least one of the following beneficial technical effects:

[0016] 1. For the molding die for improving the injection molding quality of the sector-shaped chip, by arranging an injection molding runner at the top of the rear mold core and at least two gate openings in the injection molding runner, simultaneous injection through multiple gate openings can effectively reduce the injection pressure, avoid generating internal stress in the plastic part. And by arranging an exhaust groove at the top of the rear mold core, the exhaust efficiency during injection can be ensured, avoiding the generation of vacuum bubbles in the plastic part due to poor exhaust effect, and further improving the quality of the plastic part of the chemiluminescence centrifugal disc five-in-one test chip.

[0017] 2. For the molding die for improving the injection molding quality of the sector-shaped chip, by arranging an overflow groove at the top of the rear mold core and setting the overflow port of the overflow groove at the position where the molten glue converges on the straight-side portion of the sector-shaped groove, when the molten glue converges, it will be squeezed into the overflow groove through the overflow port, and finally the excess overflow material of the plastic part is cut off, so that the weld line in the plastic part can be eliminated, and further improving the quality of the plastic part of the chemiluminescence centrifugal disc five-in-one test chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments will be briefly introduced later. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 Schematic structural diagram of a molding die for improving the injection molding quality of a fan-shaped chip according to the present invention.

[0020] Figure 2 Schematic structural diagram of the rear mold core in a molding die for improving the injection molding quality of a fan-shaped chip according to the present invention.

[0021] Figure 3 Schematic structural diagram of the mold core, insert and ejector pin in a molding die for improving the injection molding quality of a fan-shaped chip according to the present invention.

[0022] Figure 4 It is Figure 3 Enlarged structural view of part A in

[0023] Figure 5 It is Figure 3 Enlarged structural view of part B in

[0024] Figure 6 Schematic structural diagram of the mold core and insert in a molding die for improving the injection molding quality of a fan-shaped chip according to the present invention.

[0025] Figure 7 Schematic structural diagram of the mold core in a molding die for improving the injection molding quality of a fan-shaped chip according to the present invention.

[0026] Figure 8 Schematic three-dimensional sectional view of the position of the cooling water channel in the rear mold core in a molding die for improving the injection molding quality of a fan-shaped chip according to the present invention from the upward viewing angle.

[0027] Figure 9 Schematic structural diagram of a molding die for improving the injection molding quality of a fan-shaped chip during injection molding according to the present invention.

[0028] Figure 10 Schematic structural diagram of the plastic part of a molding die for improving the injection molding quality of a fan-shaped chip according to the present invention.

[0029] In the figure, 1. Mold assembly; 101. Front mold; 102. Rear mold; 2. Rear mold core; 3. Mold core; 4. Fan-shaped groove; 5. Injection runner; 6. Gate; 7. Flash groove; 8. Vent groove; 9. Through groove; 10. Insert; 11. Flash port; 12. Air channel; 13. Shallow vent port I; 14. Shallow vent port II; 15. Through hole; 16. Ejector pin; 17. Shallow vent port III; 18. Cooling water channel. Detailed implementation mode

[0030] The present invention will be further described in detail below with reference to the accompanying drawings.

[0031] Embodiment:

[0032] Refer to Figure 1 - Figure 10The present invention discloses a molding die for improving the injection molding quality of a fan-shaped chip, including a mold assembly 1, the mold assembly 1 mainly consisting of a front mold 101 and a rear mold 102, the front mold 101 and the rear mold 102 are connected by a guide mechanism;

[0033] The rear mold core 2 is connected to the top of the rear mold 102. A fan-shaped groove 4 is formed downwardly through the top of the rear mold core 2. An injection runner 5 is formed at the top of the rear mold core 2 at the outer side of the arc of the fan-shaped groove 4. At least two gates 6 for injection to the fan-shaped groove 4 are formed at intervals along the length direction of the injection runner 5. An overflow groove 7 is formed at the top of the rear mold core 2 at the side of the fan-shaped groove 4 away from the injection runner 5. An exhaust groove 8 connected to the fan-shaped groove 4 is formed at the top of the rear mold core 2 at the outer side of the straight side of the fan-shaped groove 4.

[0034] The mold core 3 is fixedly connected in the fan-shaped groove 4. A plurality of through grooves 9 are formed downwardly through the top of the mold core 3. Inserts 10 are arranged in the through grooves 9.

[0035] In this embodiment, observe Figure 1 It can be found that by providing a mold assembly 1 consisting of a front mold 101 and a rear mold 102, and the front mold 101 and the rear mold 102 are connected by a guiding mechanism, a rear mold core 2 is connected to the top of the rear mold 102, and a fan-shaped groove 4 is opened downward through the top of the rear mold core 2, and a mold core 3 is fixedly connected in the fan-shaped groove 4, so that when the front mold 101 and the rear mold 102 are closed, an injection cavity is formed between the front mold 101 and the rear mold 102, thereby being used for injection molding of a chemiluminescent centrifugal disk five-in-one detection chip plastic part.

[0036] Because all the slots on the functional surface of the chemiluminescent centrifugal disk five-in-one test chip except the microchannel need to maximize the sharp corners of the mouth to ensure the sealing effect, so the observation Figure 7 It can be found that a plurality of through grooves 9 are provided downwardly through the top of the mold core 3, and the shape of the through grooves 9 is the same as the hole shape of the chemiluminescent centrifugal disk five-in-one test chip plastic part. Figure 6 As shown, inserts 10 are connected one by one in the through grooves 9, and when processing the inserts 10, a tool with an absolutely sharp angle is used to maximize the sharp angle of the mouth, which can effectively improve the product quality of the chemiluminescent centrifugal disk five-in-one detection chip plastic part after injection molding.

[0037] However, since there are many slots in the plastic part of the chemiluminescent centrifugal disc five-inspection chip, and the bottoms of the slots are all right angles, stress concentration will occur during injection molding of the plastic part. At the same time, the injection molding pressure of PC material is generally below 130Mpa. If the holding time is short, the plastic part will shrink or shrinkage cavities and vacuum bubbles will appear. If the holding time is extended, the vacuum bubbles can be eliminated and the size is stable. However, if the holding time is too long, the plastic part is prone to internal stress and cracking. At the same time, the wall thickness of the chip body of the plastic part is 1.8mm, and the wall thickness at the slot is 1.0mm. The difference in wall thickness of the plastic part is too large, which is prone to shrinkage marks.

[0038] So combined Figure 1 and Figure 2 It can be found that an injection molding channel 5 is opened at the outer side of the arc of the fan-shaped groove 4 at the top of the rear mold core 2, and at least two gates 6 for injection molding into the fan-shaped groove 4 are spaced apart along the length direction of the injection molding channel 5. The injection molding channel 5 is arc-shaped, and the gates 6 located at both ends of the injection molding channel 5 are connected to the arc side of the fan-shaped groove 4 near the straight side, so that the chemiluminescent centrifugal disk five-in-one detection chip plastic part can be made as Figure 9 As shown, during injection molding, multiple gates 6 are used for simultaneous injection molding, which can effectively reduce the injection molding pressure, thereby avoiding the generation of internal stress in the plastic part.

[0039] Since there are holes in the plastic part of the chemiluminescent centrifugal disk five-in-one inspection chip, weld lines will inevitably appear when the melt passes over the holes, and when multiple gates 6 are injected simultaneously, weld lines will also appear at the confluence of two streams of melt, making the final plastic part look like Figure 10 As shown in the figure, the weld line appears at the C and D positions. Therefore, in order to avoid the occurrence of weld lines, observe Figure 2 It can be found that an overflow groove 7 is provided at the top of the rear mold core 2 on the side of the fan-shaped groove 4 away from the injection runner 5, so that the two ends of the overflow groove 7 are respectively connected to the two straight sides of the fan-shaped groove 4, and the overflow port 11 of the overflow groove 7 is set at the melt confluence position on the straight side of the fan-shaped groove 4. At this time, when the melt converges, it will be squeezed into the overflow groove 7 through the overflow port 11, so that the plastic part is as shown in FIG. Figure 9 As shown in the figure, the weld line can be eliminated by cutting off the excess overflow of the plastic part.

[0040] Vacuum bubbles are caused by many factors, such as too thick glue, insufficient exhaust slots, too fast injection speed, etc. The injection speed can be reduced by adjusting the parameters of the machine. The shape of the chemiluminescent centrifugal disk five-in-one inspection chip plastic part cannot be changed, so the glue thickness cannot be adjusted. Figure 2It can be found that by opening an exhaust groove 8 connected to the fan-shaped groove 4 at the top of the rear mold core 2 and located on the outer side of the straight side of the fan-shaped groove 4, and providing a plurality of shallow exhaust ports connected to the fan-shaped groove 4 in the exhaust groove 8, the exhaust efficiency can be effectively improved, the generation of vacuum bubbles can be avoided as much as possible, and the quality of the chemiluminescent centrifugal disk five-in-one inspection chip plastic parts can be further improved.

[0041] Among them, since the improvement of this application does not involve the guide mechanism, the structure and composition of the guide mechanism can adopt the existing technology and will not be elaborated here.

[0042] In a further preferred embodiment of the present invention, Figure 3 - Figure 5 As shown, the outer wall of the mold core 3 is provided with an air passage 12 for exhaust, and a shallow exhaust port 13 is provided through the top of the air passage 12 upwardly, so that when the mold core 3 is installed in the fan-shaped groove 4, a micro gap for exhaust is left between the outer wall of the mold core 3 and the inner wall of the fan-shaped groove 4;

[0043] The outer wall of the insert 10 is provided with a shallow exhaust port 14, so that when the insert 10 is inserted into the through groove 9, a micro gap 14 for exhaust is left between the outer wall of the insert 10 and the inner wall of the through groove 9;

[0044] A through hole 15 is formed downwardly through the top of the insert 10, and a ejector pin 16 is slidably disposed in the through hole 15. A shallow exhaust port 3 17 is processed on the outer wall of the ejector pin 16, so that when the ejector pin 16 is inserted into the through hole 15, a micro gap 3 for air flow is retained between the outer wall of the ejector pin 16 and the inner wall of the through hole 15.

[0045] In this embodiment, observe Figure 3 It can be found that by opening an air duct 12 for exhaust on the outer wall of the core 3, and opening a shallow exhaust port 13 through the top of the air duct 12, when the core 3 is installed in the fan-shaped groove 4, a micro gap for exhaust is left between the outer wall of the core 3 and the inner wall of the fan-shaped groove 4. Figure 4 It can be found that Figure 4 yes Figure 3 The enlarged view of point A in the middle Figure 4 It can be seen that the outer wall of the insert 10 is provided with a shallow exhaust port 14, so that when the insert 10 is inserted into the through groove 9, a micro gap 14 for exhaust is left between the outer wall of the insert 10 and the inner wall of the through groove 9.

[0046] By setting the micro gap one and the micro gap two, the exhaust efficiency can be effectively improved, so that when the chemiluminescent centrifugal disk five-inspection chip plastic product is injected, the cavity can be quickly exhausted, thereby avoiding the generation of vacuum bubbles in the chemiluminescent centrifugal disk five-inspection chip plastic product due to poor exhaust.

[0047] Since the bottom of the slot of the chemiluminescence centrifuge disc five - joint inspection chip plastic part is at a right angle, it will increase the difficulty of demolding. Therefore, in combination with Figure 3 and Figure 5 it can be found that a through - hole 15 is vertically drilled downward from the top of the insert 10, and a ejector pin 16 is slidably arranged in the through - hole 15. When the chemiluminescence centrifuge disc five - joint inspection chip plastic part is demolded, by arranging a plurality of ejector pins 16 to apply external force to the plastic part simultaneously, the excessive local pressure on the plastic part is reduced to avoid damage.

[0048] However, when the ejector pin 16 jacks up the plastic part for demolding, the distance between the inner wall of the plastic part and the mold core 3 increases, which will generate a great negative pressure to prevent demolding, and in severe cases, it will even cause the plastic part to be damaged. Therefore, in Figure 5 it can be found that a shallow exhaust port III 17 is machined on the outer wall of the ejector pin 16. When the ejector pin 16 is inserted into the through - hole 15, a micro - gap III for air flow is left between the outer wall of the ejector pin 16 and the inner wall of the through - hole 15. When the ejector pin 16 demolds, air can enter between the plastic part and the mold core 3 through the micro - gap III, avoiding the generation of negative pressure and affecting demolding, and ensuring the demolding effect of the plastic part.

[0049] In a further preferred embodiment of the present invention, as Figure 2 and Figure 8 shown, a cooling water channel 18 is arranged in the rear mold core 2, and the cooling water channel 18 surrounds the outside of the fan - shaped groove 4.

[0050] In this embodiment, by arranging a cooling water channel 18 in the rear mold core 2 and surrounding the outside of the fan - shaped groove 4, the plastic part can be cooled, accelerating the shaping of the plastic part, thereby improving the production efficiency of the plastic part.

[0051] The implementation principle of the foregoing embodiment is as follows: When producing the chemiluminescence centrifuge disc five - joint inspection chip plastic part, the molten glue is injected into the mold assembly 1 through the gating system, and the molten glue flows into the injection runner 5 along the main runner as shown in Figure 9 state, and then enters the fan - shaped groove 4 through a plurality of gates 6, so that the molten glue is shaped into the chemiluminescence centrifuge disc five - joint inspection chip plastic part under the restriction of the fan - shaped groove 4 and the mold core 3. When the molten glue is injected into the fan - shaped groove 4, the air in the fan - shaped groove 4 will be discharged through the exhaust groove 8, the micro - gap I and the micro - gap II, effectively avoiding the generation of vacuum bubbles and improving the quality of the chemiluminescence centrifuge disc five - joint inspection chip plastic part. Finally, when demolding, the front mold 101 and the rear mold 102 are separated, and the plastic part is ejected by the ejector pin 16, realizing the injection molding of the chemiluminescence centrifuge disc five - joint inspection chip plastic part.

[0052] The embodiments of the present specific implementation manners are all preferred embodiments of the present invention, and do not limit the protection scope of the present invention accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present invention should be covered within the protection scope of the present invention.

Claims

1. A molding die for improving the injection molding quality of fan-shaped chips, characterized in that: The mold assembly (1) comprises a front mold (101) and a rear mold (102), wherein the front mold (101) and the rear mold (102) are connected via a guide mechanism; A rear mold core (2) is connected to the top of the rear mold (102); a fan-shaped groove (4) is provided through the top of the rear mold core (2) and extends downward; an injection flow channel (5) is provided at the top of the rear mold core (2) and is located outside the arc of the fan-shaped groove (4); at least two gates (6) for injecting into the fan-shaped groove (4) are provided at intervals along the length direction of the injection flow channel (5); an overflow groove (7) is provided at the top of the rear mold core (2) and is located on the side of the fan-shaped groove (4) away from the injection flow channel (5); and an exhaust groove (8) is provided at the top of the rear mold core (2) and is located outside the straight side of the fan-shaped groove (4) and is connected to the fan-shaped groove (4); A mold core (3) is fixedly connected in the fan-shaped groove (4); a plurality of through grooves (9) are formed through the top of the mold core (3) and extend downward; and inserts (10) are provided in the through grooves (9); The two ends of the overflow groove (7) are respectively connected to the two straight sides of the fan-shaped groove (4), and the overflow port (11) of the overflow groove (7) is arranged at the melt-glue confluence position on the straight side of the fan-shaped groove (4); An air duct (12) for exhaust is provided on the outer wall of the mold core (3), and a shallow exhaust port (13) is provided through the top of the air duct (12) extending upward, so that when the mold core (3) is installed in the fan-shaped groove (4), a micro gap for exhaust is left between the outer wall of the mold core (3) and the inner wall of the fan-shaped groove (4); The outer wall of the insert (10) is provided with a shallow exhaust port 2 (14), so that when the insert (10) is inserted into the through groove (9), a micro gap 2 for exhaust is left between the outer wall of the insert (10) and the inner wall of the through groove (9); A through hole (15) is formed through the top of the insert (10) and extends downward therethrough. A ejector pin (16) is slidably disposed in the through hole (15). A shallow exhaust port (17) is formed on the outer wall of the ejector pin (16), so that when the ejector pin (16) is inserted into the through hole (15), a micro gap (17) for air flow is retained between the outer wall of the ejector pin (16) and the inner wall of the through hole (15); A cooling water channel (18) is provided in the rear mold core (2), and the cooling water channel (18) surrounds the outer side of the fan-shaped groove (4).

2. A molding die for improving the injection molding quality of a fan-shaped chip according to claim 1, characterized in that: The injection molding runner (5) is arc-shaped, and the gates (6) located at both ends of the injection molding runner (5) are connected to the arc side of the fan-shaped groove (4) at a position close to the straight side.

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