Mold structure for precise injection molding

Abstract

The utility model discloses a mold structure for precise injection molding, which belongs to the technical field of injection molds and comprises an injection mold body and an ejection component, the injection mold body comprises a lower mold and an upper mold, and the lower mold is matched with the upper mold. The four ejection heads push a workpiece to be separated from the upper die, uniform ejection of the workpiece is achieved, the ejection force of the bottoms of the ejection heads on the surface of the workpiece is buffered through contraction and rebound of the first springs, and therefore the workpiece in the die can be conveniently and uniformly extruded and ejected out, deformation or damage of the workpiece is avoided, and the production efficiency of the die is improved. When the upper mold and the lower mold are closed, the ejection head at the bottom end of the ejection rod is tightly attached to the limiting circular groove through resilience force generated by compressing the second spring, so that it can be ensured that the ejection head is tightly attached to the mold, liquid blanks are effectively prevented from overflowing, and the quality of workpieces is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to injection mold technical field, concretely to a mold structure for precision injection molding. BACKGROUND

[0002] Injection mold is a special tool for plastic injection molding process, it is through heating and injection plastic material into the mold cavity, then cooling solidification forms product, its principle is to utilize high pressure and inject the molten plastic material into the mold cavity, take out the shaped product after cooling, injection mold generally includes movable die and fixed die two parts, two parts can be combined, when folding, liquid blank is injected into the mold cavity and formed, after the workpiece is formed, the workpiece is demolded through the ejection mechanism.

[0003] But the existing mold structure is through the ejection mechanism to the workpiece in the mold demolding and taking out, the ejection mechanism is difficult to uniformly extrude the workpiece in the mold, which can cause uneven stress of the workpiece, resulting in deformation or damage of the workpiece, thereby reducing the quality of the workpiece, increasing the rate of defective workpiece, affecting the production efficiency of the mold, and there is a certain gap between the ejection mechanism and the mold after long time use, which can cause the overflow of liquid blank, resulting in the protrusion on the surface of the workpiece, thereby affecting the quality of the workpiece. SUMMARY

[0004] The utility model discloses a kind of mold structures for precision injection molding, the structure design of top-out assembly, spring two and ejector head, the workpiece in mold can be conveniently uniformly extruded and ejected, it can ensure that ejector head and mold are closely fitted, solve the problem that it is difficult to uniformly extrude the workpiece in the mold and cause the overflow of liquid blank.

[0005] The utility model is realized through the following technical schemes:

[0006] The utility model discloses a kind of mold structures for precision injection molding, including injection mold body and top-out assembly, injection mold body includes lower mold and upper mold, lower mold is cooperated with upper mold, upper mold is set with limit round groove, the number of limit round groove is four, limit round groove is set with through slot, upper mold is provided with U-shaped frame, the number of U-shaped frame is four, U-shaped frame is located the top of through slot, top-out assembly includes ejector rod and fixed frame, ejector rod is equipped with four, the outer surface of ejector rod is clearance fit with spring one, fixed frame is set with through hole one, the number of through hole one is four, the outer surface of ejector rod is cooperated with through hole one, spring one is located the bottom of fixed frame, the outer surface of ejector rod is cooperated with through slot, the outer surface of ejector rod is cooperated with the middle part of U-shaped frame, the outer surface of ejector rod is clearance fit spring two, fixed frame is between spring one and spring two, the bottom end of ejector rod is provided with ejector head, and ejector head is cooperated with limit round groove.

[0007] Further, the outer surface of the top rod is interference fitted with a movable ring, and the top of the movable ring is in contact with the bottom end of the spring one.

[0008] Further, the top end of the top rod is provided with a limiting disc, and the bottom surface of the limiting disc is in contact with the top end of the spring two.

[0009] Further, a through hole two is formed in the U-shaped frame, the outer surface of the top rod is matched with the through hole two, the diameter of the through hole two is same with that of the through groove, and the through hole two and the through groove are in the same vertical plane.

[0010] Further, the bottom of the lower mold is provided with a base, the mounting bracket is vertically installed on the base, the number of the mounting bracket is two, the two sides of the ejection assembly are connected with the top of the two mounting brackets, and the injection mold body is located between the two bases.

[0011] Further, the top of the upper mold is provided with a feeding nozzle.

[0012] The utility model has the following beneficial effects:

[0013] 1. The utility model discloses a structure design of the ejection assembly, the four ejection heads are pushed to make the workpiece separate from the upper mold by the lifting of the upper mold, the workpiece is evenly ejected, the spring one is contracted and rebounds, the ejection force of the bottom of the ejection head to the surface of the workpiece is buffered, so that the workpiece in the mold can be evenly extruded and ejected conveniently, the stress of the workpiece is evenly ensured when being ejected, the deformation or breakage of the workpiece is avoided, the quality of the workpiece is ensured, the defective rate of the workpiece is greatly reduced, and the production efficiency of the mold is improved.

[0014] 2. The utility model discloses the structure design of the spring two and the ejection head, when the upper mold and the lower mold are combined, the rebound force of the spring two is compressed, the ejection head at the bottom end of the top rod is tightly fitted with the limiting circular groove, so that the ejection head and the mold can be tightly fitted, the overflow of the liquid blank is avoided, the surface of the workpiece is smooth, and the quality of the workpiece is improved.

[0015] Of course, any product implementing the utility model does not necessarily need to achieve all the advantages mentioned above. DRAWINGS

[0016] Fig. 1 is a schematic view of the mold structure.

[0017] Fig. 2 is a schematic view of the top of the mold structure.

[0018] Fig. 3 is a schematic view of the assembly structure of the ejection assembly.

[0019] Fig. 4 is a schematic view of the structure of the upper mold.

[0020] Fig. 5 is a schematic diagram of the structure of the U-shaped frame.

[0021] In the figure: 1, injection mold body; 2, lower mold; 3, upper mold; 301, limit circular groove; 302, through groove; 4, ejection assembly; 401, ejector rod; 4011, movable ring; 402, spring one; 403, spring two; 404, ejector head; 405, fixed frame; 4051, through hole one; 5, mounting bracket; 6, U-shaped frame; 601, through hole two; 7, feeding nozzle; 8, base. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0023] Please refer to Figs. 1-4, the present application provides a technical solution: a mold structure for precision injection molding, comprising an injection mold body 1 and an ejection assembly 4, the injection mold body 1 comprising a lower mold 2 and an upper mold 3, the lower mold 2 cooperating with the upper mold 3.

[0024] A limit circular groove 301 is formed on the upper mold 3, the number of limit circular grooves 301 is four, a through groove 302 is formed in the limit circular groove 301, the upper mold 3 is provided with a U-shaped frame 6, the number of U-shaped frames 6 is four, the U-shaped frame 6 is located directly above the through groove 302, a through hole two 601 is formed on the U-shaped frame 6, the outer surface of the ejector rod 401 cooperates with the through hole two 601, the diameter of the through hole two 601 is the same as that of the through groove 302, the through hole two 601 and the through groove 302 are in the same vertical plane, which can facilitate the compression of the spring one 402, the upper mold 3 is provided with a feeding nozzle 7 at the top, which can facilitate the filling of liquid materials.

[0025] The ejection assembly 4 comprises four ejector rods 401, the outer surface of the ejector rod 401 is matched with spring one 402 in clearance fit, the outer surface of the ejector rod 401 is matched with movable ring 4011 in interference fit, the top of the movable ring 4011 is in contact with the bottom end of the spring one 402, which can conveniently compress the spring one 402 to buffer the extrusion force received by the workpiece, the fixed frame 405 is provided with through hole one 4051, which can facilitate the up and down movement of the ejector rod 401, the number of through hole one 4051 is four, the outer surface of the ejector rod 401 is matched with through hole one 4051, the spring one 402 is located at the bottom of the fixed frame 405, the outer surface of the ejector rod 401 is matched with the through slot 302, the outer surface of the ejector rod 401 is matched with the middle part of the U-shaped frame 6, the bottom of the lower mold 2 is provided with a base 8, the mounting bracket 5 is vertically installed on the base 8, the number of the mounting bracket 5 is two, the two sides of the ejection assembly 4 are connected with the top of the two mounting brackets 5, and the injection mold body 1 is located between the two bases 8, which can conveniently fix the ejection assembly 4.

[0026] After the injection is completed, the workpiece in the injection mold body 1 needs to be demolded and taken out, the upper mold 3 is vertically lifted by the driving device, in the process of lifting the upper mold 3, the four ejector rods 401 slide in the corresponding through slot 302 respectively, the ejector head 404 is separated from the limiting circular groove 301, so that the bottom of the four ejector heads 404 synchronously extrudes and pushes the workpiece in the upper mold 3, so that the workpiece can be uniformly separated from the upper mold 3, when the ejector head 404 extrudes the workpiece too much, the upper mold 3 is continuously moved upward, so that the U-shaped frame 6 moves upward, so that the ejector rod 401 slides in the through hole two 601 on the U-shaped frame 6, and the bottom of the movable ring 4011 is extruded by the top of the U-shaped frame 6, so that the spring one 402 is extruded between the movable ring 4011 and the fixed frame 405, after the spring one 402 is extruded, it shrinks, so that the ejector rod 401 moves upward, through the contraction and rebound of the spring one 402, the ejection force of the bottom of the ejector head 404 on the surface of the workpiece is buffered, the protection of the workpiece is realized, so that the workpiece in the mold can be conveniently extruded and ejected uniformly, the uniformity of the workpiece during ejection is effectively ensured, the deformation or damage of the workpiece is avoided, the quality of the workpiece is ensured, the scrap rate of the workpiece is greatly reduced, and the production efficiency of the mold is improved.

[0027] The outer surface of the ejector rod 401 is in clearance fit with the spring 403, the top end of the ejector rod 401 is provided with a limiting disc, the bottom surface of the limiting disc is in contact with the top end of the spring 403, the position of the spring 403 can be limited, the spring 403 is prevented from being separated from the surface of the ejector rod 401, the fixed frame 405 is located between the spring 402 and the spring 403, the bottom end of the ejector rod 401 is provided with the ejector head 404, and the ejector head 404 is matched with the limiting circular groove 301.

[0028] After the workpiece is ejected from the upper die 3, the upper die 3 is lowered through the driving device, so that the upper die 3 is combined with the lower die 2, in the process of lowering the upper die 3, the ejector rod 401 slides in the through groove 302, so that the ejector head 404 at the bottom end of the ejector rod 401 slides into the limiting circular groove 301, after the ejector head 404 is matched with the limiting circular groove 301, the upper die 3 pulls the ejector rod 401 to move downwards through the ejector head 404, so that the bottom end of the spring 403 is in contact with the surface of the fixed frame 405 and is extruded, so that the spring 403 is compressed under force, the spring 403 is compressed to generate a rebound force, the ejector rod 401 generates a vertical upward force, so that the ejector head 404 at the bottom end of the ejector rod 401 is tightly attached to the limiting circular groove 301, so that the ejector head 404 is tightly attached to the die, liquid blank overflow is effectively avoided, the surface of the workpiece is smooth, and the quality of the workpiece is improved.

[0029] The preferred embodiments disclosed above are only used for helping to describe the utility model. The preferred embodiments do not describe all the details, and the utility model is not limited to the specific implementation mode. Apparently, according to the content of the specification, many modifications and changes can be made. The embodiments are selected and described in the specification, in order to better explain the principle and practical application of the utility model, so that the person skilled in the art can well understand and utilize the utility model. The utility model is limited by the claims and the whole scope and equivalent thereof.

Claims

1. A mold structure for precision injection molding, comprising an injection mold body (1), characterized in that: The injection mold body (1) includes a lower mold (2) and an upper mold (3), wherein the lower mold (2) and the upper mold (3) are fitted together; The upper mold (3) has four limiting circular grooves (301) and a through groove (302) inside the limiting circular grooves (301). The upper mold (3) is provided with four U-shaped frames (6) and the U-shaped frames (6) are located directly above the through grooves (302). It also includes an ejector assembly (4), which includes an ejector rod (401) and a fixed frame (405). There are four ejector rods (401). A spring (402) is fitted to the outer surface of the ejector rod (401) with a clearance. A through hole (4051) is opened on the fixed frame (405). There are four through holes (4051). The outer surface of the ejector rod (401) fits with the through hole (4051). The spring (402) is located at the bottom of the fixed frame (405). The outer surface of the ejector rod (401) fits with the through groove (302). The outer surface of the ejector rod (401) fits with the middle part of the U-shaped frame (6). The outer surface of the top rod (401) is fitted with spring two (403) with clearance. The fixed frame (405) is located between spring one (402) and spring two (403). The bottom end of the top rod (401) is provided with a push head (404), which is fitted with the limiting circular groove (301).

2. The mold structure for precision injection molding according to claim 1, characterized in that, The outer surface of the push rod (401) is interference-fitted with a movable ring (4011), the top of which contacts the bottom end of the spring (402).

3. The mold structure for precision injection molding according to claim 2, characterized in that, The top of the top rod (401) is provided with a limiting disc, and the bottom surface of the limiting disc is in contact with the top of the second spring (403).

4. A mold structure for precision injection molding according to claim 3, characterized in that, The U-shaped frame (6) has a through hole 2 (601), the outer surface of the top rod (401) is fitted with the through hole 2 (601), the diameter of the through hole 2 (601) is the same as that of the through groove (302), and the through hole 2 (601) and the through groove (302) are in the same vertical plane.

5. A mold structure for precision injection molding according to any one of claims 1-4, characterized in that, The bottom of the lower mold (2) is provided with a base (8), and a mounting bracket (5) is vertically installed on the base (8). There are two mounting brackets (5). The two sides of the ejection assembly (4) are connected to the top of the two mounting brackets (5). The injection mold body (1) is located between the two bases (8).

6. A mold structure for precision injection molding according to claim 1, characterized in that, The top of the upper mold (3) is provided with a feed nozzle (7).

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