CN221809561U - A mold core pulling mechanism and injection mold - Google Patents

Abstract

The utility model discloses a mold core pulling mechanism, including a first motion module and a second motion module, the first motion module performs opening and closing motion relative to the second motion module; the first motion module is provided with a cavity, the cavity includes a first cavity and a second cavity which are positioned and connected, the radius of the first cavity is smaller than the radius of the second cavity; the second motion module is provided with a core pulling piece, the core pulling piece moves back and forth in a preset channel; the core pulling piece is inserted into the cavity and slidably connected, and a specified gap is reserved between the core pulling piece and the inner wall of the cavity. The mold core pulling mechanism provided by the utility model can effectively prevent the deformation caused by taking out the injection molded part when the product is a slender product with an aperture, improve the injection molding yield rate, and reduce the difficulty of mold design and production; the utility model also provides an injection mold, the injection mold includes a mold core pulling mechanism.

Description

A mold core pulling mechanism and injection mold

Technical Field

The utility model belongs to the technical field of injection molds, and in particular relates to a mold core pulling mechanism and an injection mold.

Background Art

Injection mold, also known as injection molding, is a kind of equipment used for injection and molding. The advantages of injection molding method are fast production speed, high efficiency, automated operation, a wide variety of colors, shapes from simple to complex, sizes from large to small, and precise product size. The product is easy to update and can be made into parts with complex shapes. Injection molding is suitable for mass production and molding processing fields such as complex-shaped products. At a certain temperature, the completely molten plastic material is stirred by a screw, injected into the mold cavity with high pressure, and the molded product is obtained after cooling and solidification. This method is suitable for mass production of parts with complex shapes and is one of the important processing methods. Injection molds are tools that are matched with plastic molding machines in the plastic processing industry to give plastic products a complete configuration and precise size. Due to the wide variety of plastics and processing methods, the structures of plastic molding machines and plastic products vary in complexity, and the types and structures of plastic molds are also diverse.

In the prior art, during the injection molding of the injection mold, some special injection molded products are sometimes encountered. Such injection molded products have some slender rods, and the inside of the slender rods also have aperture parts. In the injection molding process, because the product is too long and the radius is relatively thin, it will cause the product to deform, resulting in defective products and reducing the yield rate of injection molding; in order to reduce the occurrence of defective rates, sometimes the injection molding time has to be extended to reduce the deformation of the injection molded products. The inventor found in the injection molding production process that the prior art includes at least the following deficiencies: low injection molding efficiency, high product defective rate, and high equipment cost of the injection mold.

Utility Model Content

In view of all or part of the deficiencies of the above-mentioned prior art, the purpose of the present utility model is to provide a mold core pulling mechanism, which can reduce the possibility of deformation caused by the injection molded parts with slender rods, the interior of which also has an aperture part, and the removal of the product may cause deformation, improve the injection molding yield and injection molding efficiency, and reduce the difficulty and cost of mold design and production. In order to achieve the above-mentioned purpose of the utility model, the present utility model provides the following technical solutions: a mold core pulling mechanism, including a first motion module and a second motion module, the first motion module performs an opening and closing motion relative to the second motion module; the first motion module is provided with a cavity, the cavity includes a first cavity and a second cavity that are positioned and connected, and the radius of the first cavity is smaller than the radius of the second cavity; the second motion module is provided with a core pulling piece, the core pulling piece moves back and forth in a preset channel; the core pulling piece is inserted into the cavity and slidably connected, and a specified gap is reserved between the core pulling piece and the inner wall of the cavity.

This solution realizes the sliding connection between the cavity on the first motion module and the core-pulling part on the second motion module by opening and closing the first motion module and the second motion module; during the opening and closing process, the core-pulling action is automatically performed on the product in the cavity; the second motion module is fixedly connected to the core-pulling part, and the core-pulling part moves back and forth driven by the second motion module, and the injection molded product is first core-pulled and then removed from the material, which can prevent the deformation of the injection molded part caused by taking out the product when it is a slender product with an aperture, thereby improving the injection molding yield rate, and this structure is very simple, which reduces the difficulty of mold design and production, and greatly reduces the cost of the mold.

When the aperture of the injection molded product is a through hole, one end of the core pulling piece needs to pass through the cavity. To achieve this purpose, an opening is provided at one end of the first cavity away from the second cavity, and the opening can accommodate one end of the core pulling piece to pass through.

The second motion module is provided with a core puller, which slides in the cavity, and a specified gap is reserved between the core puller and the inner wall of the cavity. The specified gap reserved between the core puller and the cavity is 0.4 mm.

The length of the core pulling member is greater than the length of the cavity, one end of the core pulling member passes through the opening of the first cavity, and an escape space is correspondingly provided outside the first cavity.

The core-pulling part is a formed insert pin, and the formed insert pin is a metal part.

The front end of the molding pin is a first column shape, and the rear end is a second column shape, and the radius of the first column shape is smaller than the radius of the second column shape.

The connection between the first column and the second column is a second cone.

The first column can be inserted into the first cavity, and the second column can be inserted into the second cavity; a gap is reserved between the second column and the first cavity. The gap reserved between the second column and the first cavity is 0.4 mm.

An injection mold comprises a front mold, a push plate, a rear mold and the above-mentioned mold core pulling mechanism.

Compared with the prior art, the utility model has at least the following beneficial effects: the scheme realizes the sliding connection between the cavity on the first motion module and the core pulling part on the second motion module by the mutual opening and closing movement of the first motion module and the second motion module; during the opening and closing process, the core pulling action is automatically performed on the product in the cavity; the second motion module is fixedly connected to the core pulling part, and the core pulling part moves back and forth in a preset channel under the drive of the second motion module, and the injection molded product is first cored and then removed, which can reduce the deformation caused by taking out the injection molded product that is a slender product with an aperture, and improve the injection molding yield rate, and this structure is very simple, which reduces the difficulty of mold design and production, and greatly reduces the cost of the mold.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the specific embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

Figure 1 is a schematic diagram of a mold core pulling mechanism of the utility model;

FIG. 2 is a structural diagram of a mold with a core pulling mechanism.

Figure numerals: 1-first motion module, 101-first cavity, 102-second cavity, 103-opening, 2-second motion module, 201-core pulling part, 2011-first column, 2012-second column, 3-first cone, 4-second cone, 5-limiting block.

DETAILED DESCRIPTION

The technical solutions in the specific embodiments of the utility model are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

Example 1

As shown in Figures 1 and 2, an embodiment of a mold core pulling mechanism of the utility model is adopted. In real life, there are various injection molded products, and different injection molds are required to match different injection molded products. In this embodiment, the injection molded product is a plastic suction head, and the suction head has a hole diameter of only 0.66mm, but the length reaches 40mm. Such a large aspect ratio is easy to cause product deformation under the action of force during the injection molding process. Therefore, whether the problem of product deformation can be solved is the key to the success or failure of this set of molds.

According to Hooke's law, the deformation of an object is proportional to the external force that causes the deformation, so we need to reduce the force on the product; at the same time, according to the characteristics of the resin, the resin has a higher hardness below the glass transition temperature, so we need to strengthen the mold cooling as much as possible to make the resin in the cavity reach below the glass transition temperature as soon as possible. The glass transition temperature (Tg) refers to the temperature corresponding to the transition from the glass state to the highly elastic state; the glass transition is an inherent property of amorphous polymer materials and a macroscopic manifestation of the transformation of the polymer motion form, which directly affects the material's performance and process performance. In this embodiment, it should be noted that in order to describe the technical solution more specifically, the steps described in this embodiment do not strictly correspond to the steps described in the utility model content part.

The utility model provides the following technical solutions: a mold core pulling mechanism, including a first motion module 1 and a second motion module 2, the first motion module 1 performs an opening and closing motion relative to the second motion module 2; a cavity is provided on the first motion module 1, the cavity includes a first cavity 101 and a second cavity 102, the first cavity 101 and the second cavity 102 are fixedly connected, and the connection presents a first cone 3; a core pulling piece 201 is provided on the second motion module 2, and the core pulling piece 201 is provided with a predetermined channel; the core pulling piece 201 can slide in the cavity. A specified gap is reserved between the core pulling piece 201 and the inner wall of the cavity. The specified gap reserved between the core pulling piece 201 and the cavity is 0.2-0.8mm, preferably 0.4mm, and the reserved gap is used for injection molding products, and the thickness of the gap is the thickness of the product.

In this embodiment, the first motion module 1 is the front mold of the mold, and the second motion module 2 is the rear mold of the mold. The definitions of the front mold and the rear mold are relative, and they can also be interchanged in other embodiments. The front mold and the rear mold are respectively connected to a driving member, and the core-pulling member 201 fixedly connected to the rear mold follows the rear mold to make a reciprocating motion in a preset channel, and the injection molded product is first core-pulled and then removed, which can reduce the deformation caused by the removal of the injection molded product that is a slender product with an aperture, improve the injection molding yield, and reduce the difficulty of mold design and production. In addition, this structure is very simple, which reduces the difficulty of mold design and production, and greatly reduces the cost of the mold.

Preferably, the core-pulling member 201 and the rear mold are fixedly connected by a preset thread, and different core-pulling members 201 can be replaced according to the needs of the product. Different core-pulling members 201 have different lengths and radii, and can be used to inject products with different aperture depths and different thicknesses; a variety of different products can be injected, and both through holes and countersunk holes can achieve core-pulling action, thereby improving the utilization rate of injection molding equipment and reducing the difficulty and cost of mold design and production. When the aperture of the injection molded product is a through hole, one end of the core-pulling member 201 needs to pass through the cavity. To achieve this purpose, an opening 103 is provided at one end of the first cavity 101 away from the second cavity 102, and the opening 103 can accommodate one end of the core-pulling member 201 passing through. An avoidance space is correspondingly provided on the outside of the first cavity 101, and a limit block 5 is provided at the position of the avoidance space directly opposite the core-pulling member 201. After one end of the core-pulling member 201 passes through the opening 103, it abuts against the limit block 5 and then stops moving. In other embodiments, the length of the core puller 201 may be no greater than the length of the cavity, one end of the core puller 201 does not pass through the cavity, the core puller 201 passes through the second cavity 102 and is located inside the first cavity 101, and the hole on the slender rod of the injection molded product is a countersunk hole. In other embodiments, the core puller 201 may also pass through the rear mold and be provided with an independent drive system, and the core puller is performed at an appropriate time according to the needs of the injection molded product to reduce the defective rate of the injection molded product.

In this embodiment, the core-pulling part 201 is a molding pin, which can be a metal part. The molding pin can be a metal part with beryllium copper wrapped around the outer ring, or a molding pin made of beryllium copper and/or other metals. The thermal conductivity of beryllium copper at room temperature is 400W/(M·k), while the thermal conductivity of steel is only about 50W/(M·k). The strong thermal conductivity of beryllium copper can achieve rapid conduction and temperature reduction, so as to improve the injection molding efficiency and reduce the defect rate; the molding pin can move with the movement of the rear mold. The front end of the molding pin is a first column 2011, and the rear end is a second column 2012. The radius of the first column 2011 is smaller than the radius of the second column 2012. The connection between the first column 2011 and the second column 2012 is the second cone 4. The bottom radius of the second cone 4 is slightly smaller than the bottom radius of the first cone 3, and an escape space is provided between the second cone 4 and the first cone 3. The first column 2011 is inserted into the first cavity 101, and the second column 2012 is inserted into the second cavity 102; a gap is reserved between the second column 2012 and the first cavity 101. A gap is reserved between the second column 2012 and the first cavity 101 for injection molding products, and the gap is 0.2-0.8 mm, preferably 0.4 mm.

The utility model also provides an injection mold, including a front mold, a push plate, a rear mold and the mold core pulling mechanism. The injection mold provided by the scheme first pulls the core and then demolds the mold through the core pulling mechanism, so that the product is not easy to deform, the yield rate of injection molded products is improved, the structure is simple, and cost and space are saved.

The above embodiments are only used to help understand the method and core idea of the utility model. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the utility model, the utility model can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the utility model.

Claims (10)

1. The utility model provides a mould mechanism of loosing core which characterized in that: comprises a first motion module (1) and a second motion module (2); the first movement module (1) is provided with a cavity, the cavity comprises a first cavity (101) and a second cavity (102), the first cavity (101) is fixedly connected with the second cavity (102), and the radius of the first cavity (101) is smaller than that of the second cavity (102); the second movement module (2) is provided with a core pulling member (201), and the core pulling member (201) moves back and forth in a preset channel; the core pulling piece (201) slides in the cavity, and a gap is reserved between the core pulling piece (201) and the inner wall of the cavity.

2. The mold core pulling mechanism according to claim 1, wherein: an opening (103) is formed in one end, away from the second cavity (102), of the first cavity (101), and one end, containing the core pulling piece (201), of the opening (103) can penetrate through the opening.

3. The mold core pulling mechanism according to claim 2, wherein: when the core pulling member (201) is inserted into the cavity, a gap reserved between the core pulling member (201) and the cavity is 0.4mm.

4. The mold core pulling mechanism according to claim 2, wherein: the length of the core pulling piece (201) is greater than that of the cavity, one end of the core pulling piece (201) penetrates through the opening (103) of the first cavity (101), and an avoidance space is correspondingly formed outside the first cavity (101).

5. The mold core pulling mechanism according to any one of claims 1 to 4, wherein: the core pulling piece (201) is a molding insert pin, and the molding insert pin is a metal piece.

6. The mold core pulling mechanism according to claim 5, wherein: the front end of the formed insert pin is a first cylinder (2011), the rear end of the formed insert pin is a second cylinder (2012), and the radius of the first cylinder (2011) is smaller than that of the second cylinder (2012).

7. The mold core pulling mechanism according to claim 6, wherein: the junction of the first pillar (2011) and the second pillar (2012) is a second cone (4).

8. The mold core pulling mechanism according to claim 6, wherein: -the first cylinder (2011) is insertable into the first cavity (101) and the second cylinder (2012) is insertable into the second cavity (102); a gap is reserved between the second cylinder (2012) and the first cavity (101).

9. The mold core pulling mechanism according to claim 8, wherein: a gap of 0.4mm is reserved between the second cylinder (2012) and the first cavity (101).

10. An injection mold, characterized in that: comprising a front mold, a push plate, a rear mold and a core-pulling mechanism for a mold according to any one of claims 1 to 9.