Mold structure for improving air trapping in silica gel injection molding

Abstract

The utility model discloses a mould structure for improving air trapping in silica gel injection molding, which comprises a first insert, a second insert, a rear mould insert pin, a front mould insert pin, a flash groove, an exhaust groove and an exhaust channel, opposite surfaces of the first insert and the second insert are provided with a first injection hard rubber product positioning cavity, a first injection hard rubber product is preassembled at the first injection hard rubber product positioning cavity, and a second injection hard rubber product is preassembled at the first injection hard rubber product positioning cavity. A rear mold insert pin is vertically inserted into the first insert, a front mold insert pin is vertically inserted into the second insert, a through second-injection LSR silica gel product forming cavity is formed in the face, opposite to a first-injection hard rubber product, of the second insert and the front mold insert pin, a plurality of flash grooves communicated with the second-injection LSR silica gel product forming cavity are formed in the vertical direction of the second-injection LSR silica gel product forming cavity, and the flash grooves are communicated through exhaust grooves. The die is further provided with an exhaust channel communicated with the exhaust groove. By means of the mode, exhaust can be improved, the increased die cost is very small, the phenomenon that an overflow part is attached to a one-shot hard rubber product is avoided, and the post-processing procedure of the product is reduced.

Description

Technical Field

[0001] This utility model relates to the field of mold technology, and in particular to a mold structure for improving air trapping in silicone injection molding. Background Technology

[0002] Figure 1 For injection molded products, including one-shot rigid silicone product a and two-shot LSR silicone product b, liquid silicone is prone to air entrapment and short-filling at the flow end during injection molding. Conventional methods are insufficient for venting this air, leading to product defects and affecting functionality. Therefore, an overflow tray is needed. When LSR silicone products require overflow, an overflow groove is added laterally in the mold where there is no product residue. Figure 2 and Figure 3 As shown, since the two-shot LSR silicone product b is horizontally wrapped inside the one-shot rigid silicone product a, a material feeding area c needs to be opened on the side of the original one-shot rigid silicone product a. The overflow groove is connected to the material feeding area c. The material feeding area c affects the product characteristics. The overflow groove is located on the periphery of the product. When the silicone is molded, the silicone in the overflow groove area is easy to stick to the original one-shot rigid silicone product a, which is difficult to handle later.

[0003] However, the overflow package cannot affect the product size while venting the air, so opening the overflow package inside the product has become a rather tricky problem. Based on the above defects and shortcomings, it is necessary to improve the existing technology and design a mold structure to improve the air trapping in silicone injection molding. Utility Model Content

[0004] The main technical problem solved by this utility model is to provide a mold structure that improves air entrapment in silicone injection molding. The structure is simple, which can improve air venting and increases the mold cost by very little. It also prevents overflow from sticking to the injection-molded hard plastic product and reduces the number of post-processing steps.

[0005] To solve the above-mentioned technical problems, the present invention adopts a technical solution as follows: A mold structure for improving air trapping in silicone injection molding is provided. This mold structure includes a first insert, a second insert, a rear mold insert, a front mold insert, an overflow groove, a venting groove, and a venting channel. The first insert is disposed in the male mold, and the second insert is disposed in the female mold. A positioning cavity for a single-shot rigid rubber product is provided on the opposite surface of the first and second inserts. A single-shot rigid rubber product is pre-installed in the positioning cavity. A rear mold insert is vertically inserted on the first insert, and a front mold insert is vertically inserted on the second insert. A through-hole two-shot LSR silicone product molding cavity is provided on the opposite surface of the second insert and the front mold insert to the single-shot rigid rubber product. Several overflow grooves are vertically arranged in the two-shot LSR silicone product molding cavity and communicate with it. The overflow grooves are connected through the venting groove. A venting channel communicating with the venting groove is also provided on the mold.

[0006] Preferably, the overflow channel is vertically arranged, the cross-section of the overflow channel is inverted triangular, and the connection between the overflow channel and the molding cavity of the two-shot LSR silicone product is the tip of the inverted triangle.

[0007] Preferably, a mold structure for improving air trapping in silicone injection molding further includes a straight ejector block, which is movably inserted into the mold master mold. The lower part of the straight ejector block extends horizontally outward to form an ejector portion. The overflow groove is provided on the side end of the ejector portion, and the venting groove is provided on the side end and the top surface of the ejector portion, communicating with the overflow groove.

[0008] Compared with the prior art, the beneficial effects of this utility model are:

[0009] From a vertical projection perspective, the overflow channels are set within the product area. Multiple overflow channels are connected through venting channels and communicate with the outside of the mold through venting channels, which can solve the problem of trapped air in silicone injection molding.

[0010] The overflow trough is set vertically to prevent overflow from sticking to the one-shot rigid plastic product, thus reducing the number of post-processing steps.

[0011] The overflow groove is set on the straight ejector block, which can push the overflow groove out for easy removal later, and the overflow will not remain inside the mold. Attached Figure Description

[0012] Figure 1 This is a structural diagram of an injection-molded product.

[0013] Figure 2 A schematic diagram illustrating how existing technologies can solve the problem of trapped air in silicone injection molding.

[0014] Figure 3 for Figure 2 Sectional view.

[0015] Figure 4 This is a schematic diagram of a mold structure for improving air trapping during silicone injection molding.

[0016] Figure 5 This is a schematic diagram of the internal structure of a mold structure for improving air trapping in silicone injection molding.

[0017] Figure 6 This is a partial structural diagram of a mold structure for improving air trapping during silicone injection molding.

[0018] Among them, 1. First insert, 2. Second insert, 3. Rear mold insert, 4. Front mold insert, 5. Overflow groove, 6. Venting groove, 7. Venting channel, 8. Straight ejector block, 80. Ejector section. Detailed Implementation

[0019] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the scope of protection of the present invention.

[0020] Please see Figures 1 to 6 The embodiments of this utility model include:

[0021] A mold structure for improving air trapping in silicone injection molding includes a first insert 1, a second insert 2, a rear mold insert 3, a front mold insert 4, an overflow groove 5, an venting groove 6, and an venting channel 7.

[0022] The first insert 1 is disposed in the male mold, and the second insert 2 is disposed in the female mold. A positioning cavity for a first-shot hard rubber product is disposed on the opposite surface of the first insert 1 and the second insert 2. A first-shot hard rubber product is pre-installed in the positioning cavity. A rear mold insert pin 3 is vertically inserted on the first insert 1, and a front mold insert pin 4 is vertically inserted on the second insert 2. A through-hole cavity for a second-shot LSR silicone product is disposed on the opposite surface of the second insert 2 and the front mold insert pin 4 and the first-shot hard rubber product. A plurality of overflow grooves 5 are vertically disposed in the cavity for the second-shot LSR silicone product, and the plurality of overflow grooves 5 are connected through a venting groove 6. A venting channel 7 communicating with the venting groove 6 is also provided on the mold.

[0023] The overflow groove 5 is vertically arranged, and the overflow material at the overflow groove 5 does not come into contact with the first-shot rigid rubber product. The cross-section of the overflow groove 5 is inverted triangular, and the connection between the overflow groove 5 and the molding cavity of the second-shot LSR silicone product is the tip of the inverted triangle. The connection surface between the overflow groove 5 and the molding cavity of the second-shot LSR silicone product is narrow, which facilitates the subsequent removal of overflow material.

[0024] A mold structure for improving air trapping in silicone injection molding also includes a straight ejector block 8, which is movably inserted into the mold mother mold. The lower part of the straight ejector block 8 extends horizontally outward to form an ejector portion 80. The overflow groove 5 is provided on the side end of the ejector portion 80, and the venting groove 6 is provided on the side end and the top surface of the ejector portion 80, connecting to the overflow groove 5. If the overflow groove 5 is vertical, it will remain inside the mold. By setting the overflow groove 5 on the straight ejector block 8, the straight ejector block 8 can eject the overflow groove 5 for easy removal later.

[0025] This utility model discloses a mold structure for improving air trapping in silicone injection molding. The structure is simple, which can improve air venting with minimal increase in mold cost. It also prevents overflow from sticking to the injection-molded hard plastic product, reduces post-processing steps, and achieves the effect of solving key problems with a simple structure.

[0026] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A mold structure for improving air trapping during silicone injection molding, characterized in that: The mold includes a first insert, a second insert, a rear mold insert pin, a front mold insert pin, an overflow groove, a venting groove, and a venting channel. The first insert is located in the male mold, and the second insert is located in the female mold. A positioning cavity for a single-shot rigid rubber product is provided on the opposite surface of the first insert and the second insert. A single-shot rigid rubber product is pre-installed in the positioning cavity. A rear mold insert pin is vertically inserted on the first insert, and a front mold insert pin is vertically inserted on the second insert. A through-hole cavity for a two-shot LSR silicone product is provided on the opposite surface of the second insert and the front mold insert pin and the single-shot rigid rubber product. Several overflow grooves are vertically arranged in the two-shot LSR silicone product molding cavity and are connected to it. Several overflow grooves are connected through the venting groove. The mold also has a venting channel that is connected to the venting groove.

2. The mold structure for improving air trapping in silicone injection molding according to claim 1, characterized in that: The overflow groove is vertically arranged, and the cross-section of the overflow groove is inverted triangular. The connection between the overflow groove and the molding cavity of the two-shot LSR silicone product is the tip of the inverted triangle.

3. The mold structure for improving air trapping in silicone injection molding according to claim 1, characterized in that: It also includes a straight ejector block, which is movably inserted into the mold master mold. The lower part of the straight ejector block extends horizontally outward to form an ejector portion. The overflow groove is set at the side end of the ejector portion, and the venting groove is set at the side end and the top surface of the ejector portion, connecting to the overflow groove.

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