Melt exhaust injection molding insert pin

Abstract

The utility model relates to the technical field of injection molds, in particular to a melt exhaust injection molding insert pin which comprises a pin body, a pressing cap is arranged at the outer end of the pin body, a penetrating head is arranged at the inner end of the pin body, a gas gathering groove is formed between the penetrating head and the pin body, and a directional exhaust groove facing a weld line is formed in the pin body. The needle body is provided with a directional exhaust groove, the directional exhaust groove extends to the outer end of the needle body, the exhaust groove is communicated with the gas gathering groove, the pressing cap is provided with an exhaust port communicated with the exhaust groove, the needle body is further connected with an angle positioning structure, the exhaust groove faces the weld line, and in the melt flowing process, when encountering the weld line, air can preferentially flow along the directional exhaust groove, and the air can be discharged out of the needle body. And therefore, air is more easily gathered near the directional exhaust groove and is exhausted, and the performance of the injection molding part is improved.

Description

Technical Field

[0001] This utility model relates to the field of injection mold technology, and in particular to melt venting injection pins. Background Technology

[0002] During injection molding, due to their complex internal structure and internal pores, air within the mold cavity is difficult to expel smoothly. Traditional internal inserts have many shortcomings in venting, often leading to defects such as air bubbles and trapped air, affecting product quality. One important reason is that the insert's structure does not consider the relationship between the venting direction and the weld line; the venting direction is relatively random, causing interference between weld line formation and air venting, making it impossible to effectively expel air from the mold cavity to the outside. Utility Model Content

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a melt venting injection pin that can make the venting groove face the weld line.

[0004] This utility model is achieved through the following technical solution: a melt venting injection molding insert, comprising a needle body, a pressure cap provided at the outer end of the needle body, a through-hole provided at the inner end of the needle body, a gas gathering groove provided between the through-hole and the needle body, a directional venting groove provided on the needle body facing the weld line direction, the directional venting groove extending to the outer end of the needle body, the venting groove communicating with the gas gathering groove, a venting port provided on the pressure cap communicating with the venting groove, and an angle positioning structure connected to the needle body.

[0005] Furthermore, the sidewall of the exhaust port cap is provided such that the exhaust port extends to the outer end of the cap.

[0006] Furthermore, the radial positioning structure includes a positioning groove disposed on the pressure cap.

[0007] Furthermore, the radial positioning structure includes positioning protrusions disposed on the pressure cap.

[0008] Furthermore, the radial positioning structure includes a positioning port disposed at the exhaust port opening.

[0009] The beneficial effects of this utility model are as follows: the venting groove is oriented towards the weld line. During the melt flow process, when it encounters the weld line, the air will preferentially flow along the directional venting groove, making it easier for the air to gather near the directional venting groove and be discharged, thereby improving the performance of the injection molded part. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of Example 1;

[0011] Figure 2This is a schematic diagram of the second orientation structure in Example 1;

[0012] Figure 3 This is a schematic diagram of the cap structure in Example 2;

[0013] Figure 4 This is a schematic diagram of the cap structure in Example 3.

[0014] The components are: 1. Needle body; 2. Pressure cap; 3. Exhaust groove; 4. Exhaust port; 5. Puncture head; 6. Variable diameter section; 7. Condensation section; 8. Blocking section; 9. Gas gathering groove; 10. Positioning groove; 11. Positioning protrusion; 12. Positioning port. Detailed Implementation

[0015] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0017] Example 1

[0018] like Figure 1-2 As shown, a melt venting injection molding insert is used in injection molds with complex internal structures and internal holes. It includes a needle body 1, which is made of stainless steel, has strong resistance to deformation, and is easy to separate from the injection molded part. The outer end of the needle body 1 is integrally formed with a pressure cap 2, which then mates with a mounting hole. The mounting hole is a stepped hole, and the pressure cap 2 mates with the stepped surface of the stepped hole.

[0019] The needle body 1 has an integrally formed piercing head 5 at its inner end. The outer diameter of the piercing head 5 is 1 / 2 to 2 / 3 of the outer diameter of the needle body 1, making it easier for the piercing head 5 to extend into the melt, destroy the local structure of the melt, and thus accelerate the gas outflow. The outer end of the piercing head 5 is coaxially connected to a variable diameter section 76, and the outer end of the variable diameter section 76 is coaxially connected to a condensing section. The outer diameter of the variable diameter section 76 gradually increases from the piercing head 5 to the condensing section, and correspondingly, the melt wall thickness gradually decreases. It can quickly condense at the condensing section, thus blocking the melt from flowing outward. The outer end of the condensing section is coaxially connected to a blocking section 8. The gap between the blocking section 8 and the stepped hole is 0.1-0.15mm, thus ensuring the stable outflow of gas. There is a gas gathering groove 9 between the blocking section 8 and the needle body 1. The gas gathering groove 9 is an annular groove, and the gap between the bottom of the gas gathering groove 9 and the stepped hole is 0.2-0.25mm, thus forming a connecting cavity, allowing the gas to quickly gather and be discharged.

[0020] The needle body 1 is machined with a directional venting groove 3 facing the weld line direction. The directional venting groove 3 extends to the outer end of the needle body 1. The distance between the bottom of the directional venting groove 3 and the stepped hole is 0.2-0.25mm, and the width is 0.2-0.3mm. The venting groove 3 is connected to the gas gathering groove 9, which can ensure that the airflow flows out quickly. The pressure cap 2 is machined with a venting port 4 connected to the venting groove 3. The venting port 4 is distributed on the side wall of the pressure cap 2 and extends to the outer end of the pressure cap 2, which can allow the airflow to be discharged to the outside of the mold. The outer end of the stepped hole is connected to the venting groove of the mold, which can quickly discharge the airflow.

[0021] The needle body 1 is also connected to an angle positioning structure. Specifically, the radial positioning structure includes a positioning groove 10 machined on the pressure cap 2. Before mold opening, the weld line position can be pre-confirmed through DFM simulation. Then, a stepped hole is machined, and a positioning block that mates with the positioning groove 10 is machined on the side wall of the stepped hole. The needle body 1 is inserted into the stepped hole by a through-fitting method. The angle of the needle body 1 is positioned by the cooperation of the positioning block and the positioning groove 10, thereby positioning the angle of the venting groove 3, so that the venting groove 3 faces the weld line direction. Air will preferentially flow along the directional venting groove 3, making it easier for air to gather near the directional venting groove 3 and be discharged, thereby improving the performance of the injection molded part.

[0022] In this embodiment, the exhaust groove 3 can be obtained by cutting the edge or by milling.

[0023] Example 2

[0024] like Figure 3 As shown, a melt venting injection molding insert differs from Embodiment 1 in that the radial positioning structure includes a positioning protrusion 11 integrally formed on the pressure cap 2, and a groove that mates with the positioning protrusion 11 is machined on the side wall of the stepped hole.

[0025] Example 3

[0026] like Figure 4 As shown, a melt venting injection molding insert differs from embodiments 1-2 in that its radial positioning structure includes a positioning port 12 machined at the opening of the venting port 4, and a guide block that mates with the positioning port 12 is machined on the side wall of the stepped hole.

[0027] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A melt venting injection molding insert, comprising a needle body, a pressure cap disposed at the outer end of the needle body, a through-hole head disposed at the inner end of the needle body, and an air-gathering groove disposed between the through-hole head and the needle body, characterized in that, The needle body is provided with a directional venting groove facing the direction of the fusion line. The directional venting groove extends to the outer end of the needle body. The venting groove is connected to the gas gathering groove. The pressure cap is provided with a venting port connected to the venting groove. The needle body is also connected to an angle positioning structure.

2. The melt venting injection molding insert according to claim 1, characterized in that, The sidewall of the exhaust port cap is provided, and the exhaust port extends to the outer end of the cap.

3. The melt venting injection molding insert according to claim 2, characterized in that, The radial positioning structure includes a positioning groove disposed on the pressure cap.

4. The melt venting injection molding insert according to claim 2, characterized in that, The radial positioning structure includes positioning protrusions provided on the pressure cap.

5. The melt venting injection molding insert according to claim 2, characterized in that, The radial positioning structure includes a positioning port disposed at the exhaust port opening.

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