CN223211818U

CN223211818U - Plastic lampshade injection molding device and mold assembly thereof

Info

Publication number: CN223211818U
Application number: CN202521159638.XU
Authority: CN
Inventors: 封正勇; 李聪林; 蒲佳穗; 廖伟; 石帅; 李述财; 王涛
Original assignee: Sichuan Energy Investment Intelligent Photoelectric Co ltd
Current assignee: Sichuan Energy Investment Intelligent Photoelectric Co ltd
Priority date: 2025-06-09
Filing date: 2025-06-09
Publication date: 2025-08-12
Anticipated expiration: 2035-06-09

Abstract

The utility model relates to a plastic lampshade injection molding device and a mold assembly thereof, belonging to the field of lampshade production equipment. The mold assembly includes a mold base, a lower mold fixedly provided on the mold base, an upper mold provided above the lower mold, a raised mold core provided on the upper surface of the lower mold, a groove provided on the lower surface of the upper mold, the mold core and the groove enclosing a molding cavity, and an injection port connected to the molding cavity provided on the top of the upper mold; a positioning groove provided on the upper surface of the lower mold, a lifting seat provided in the positioning groove that slides with the positioning groove, the upper end of the lifting seat fixedly connected to the mold core, and the lower end of the lifting seat connected to a lifting mechanism. The utility model can reduce the resistance during injection, and at the same time, utilize the mold core to extrude the molten plastic, prompting the molten plastic to quickly fill the molding cavity, thereby improving the injection molding efficiency and ensuring the quality of the lampshade.

Description

Plastic lampshade injection molding device and mold assembly thereof

Technical Field

The utility model belongs to the field of lamp shade production equipment, and particularly relates to an injection molding device for a plastic lamp shade and a mold assembly of the injection molding device.

Background

Plastic lamp covers are very common at present, and are usually formed by injection molding. To the lamp shade of different shapes and sizes, need prepare corresponding injection mold, current injection mold generally includes cover half and movable mould, encloses into the die cavity between cover half and the movable mould, is provided with the injection molding mouth on the movable mould, and inside cooling body and the ejection mechanism of can also setting up of mould to accelerate lamp shade cooling solidification and be convenient for the drawing of patterns. Because the lampshade is usually small in thickness, molten plastics are difficult to quickly and uniformly fill the cavity, and the production efficiency and the production quality of the lampshade are affected.

Disclosure of utility model

The utility model aims to solve the technical problem of providing a plastic lampshade injection molding device and a mold assembly thereof, which can promote molten plastic to quickly and uniformly fill a cavity.

In order to solve the problems, the technical scheme adopted by the utility model is that the die assembly comprises a die holder, a lower die is fixedly arranged on the die holder, an upper die is arranged above the lower die, a raised die core is arranged on the upper surface of the lower die, a groove is arranged on the lower surface of the upper die, the die core and the groove form a die cavity in a surrounding manner, and an injection molding port communicated with the die cavity is arranged at the top of the upper die;

The upper surface of lower mould is provided with the constant head tank, be provided with in the constant head tank with constant head tank sliding fit's lifting seat, the upper end and the mold core fixed connection of lifting seat, the lower extreme of lifting seat is connected with elevating system.

Further, a vertical guide post is arranged on the die holder, and the guide post penetrates through the upper die and is in sliding fit with the upper die.

Further, a detachable one-way valve is arranged in the injection molding opening.

Further, the lifting mechanism is a hydraulic cylinder.

Further, an exhaust groove is formed in the inner wall of the injection molding opening or the parting surface of the lower die and the upper die.

Further, a cooling cavity is arranged in the mold core, a cooling medium inlet and a cooling medium outlet which are communicated with the cooling cavity are arranged on the bottom surface of the lifting seat, the cooling medium inlet is connected with a cooling medium supply mechanism through a first hose, and the cooling medium outlet is connected with a second hose.

Further, the cooling medium supply mechanism includes a water tank connected to the first hose via a water pump, and the second hose is connected to the water tank.

Further, a valve is arranged on the second hose, a plurality of vertical ejection through holes are formed in the upper surface of the mold core, ejector rods which are in sliding fit with the ejection through holes are arranged on the upper portions of the ejection through holes, supporting blocks are fixedly arranged on the lower portions of the ejection through holes, the upper surfaces of the supporting blocks are in contact with the lower surfaces of the ejector rods, and medium through holes communicated with the cooling cavity are formed in the supporting blocks.

The plastic lampshade injection molding device comprises the die assembly.

The mold core is arranged on the lifting seat, and the mold core can be driven to move up and down by the lifting seat, so that the position of the mold core is adjusted, and the size of a cavity formed by the mold core and the upper mold groove is changed. During injection molding, the mold core is driven to move downwards, so that the cavity is enlarged, and the injection resistance can be reduced. Then injecting molten plastic into the cavity through the injection port, stopping injecting when the injection quantity reaches the volume of the lampshade, and then driving the lifting seat and the mold core to move upwards by utilizing the lifting mechanism, wherein the mold core can extrude the plastic, so that the plastic is enabled to quickly and uniformly fill the whole cavity.

Drawings

FIG. 1 is a schematic cross-sectional view of the present utility model;

FIG. 2 is an enlarged schematic view of an ejector structure;

The numerical control machine comprises a 1-die holder, a 2-lower die, a 3-upper die, a 4-die core, a 5-die cavity, a 6-injection port, a 7-lifting seat, an 8-lifting mechanism, a 9-guide post, a 10-one-way valve, an 11-cooling cavity, a 12-cooling medium inlet, a 13-cooling medium outlet, a 14-first hose, a 15-cooling medium supply mechanism, a 16-second hose, a 17-water pump, a 18-valve, a 19-ejector rod, a 20-support block and a 21-medium through hole.

Detailed Description

The utility model will be further described with reference to the drawings and examples.

The die assembly of the utility model, as shown in figure 1, comprises a die holder 1, wherein the die holder 1 adopts a metal plate with larger thickness, and can be a rectangular plate or a circular plate. The die holder 1 is fixedly provided with the lower die 2, and the lower die 2 can be welded with the die holder 1, and as a preferred embodiment, the lower die 2 is connected with the die holder 1 through bolts so as to replace the lower dies 2 with different types and specifications, and the utilization rate of the die holder 1 is improved. The upper die 3 is arranged above the lower die 2, the raised die core 4 is arranged on the upper surface of the lower die 2, the groove is arranged on the lower surface of the upper die 3, after the upper die 3 and the lower die 2 are assembled, the die core 4 and the groove enclose a forming cavity 5, the shape and the size of the cavity 5 are matched with those of a lampshade to be processed, and an injection molding opening 6 communicated with the cavity 5 is arranged at the top of the upper die 3. The injection port 6 is used to inject molten plastic into the cavity 5.

The upper surface of lower mould 2 is provided with the constant head tank, is provided with in the constant head tank with constant head tank sliding fit's lifting seat 7, the upper end and the mold core 4 fixed connection of lifting seat 7, the lower extreme of lifting seat 7 is connected with elevating system 8.

The mold core 4 can be connected with the lifting seat 7 through screws, and can also be integrally formed with the lifting seat 7. The lifting mechanism 8 can push the lifting seat 7 and the mold core 4 to synchronously lift, after the upper mold 3 and the lower mold 2 are assembled, if the mold core 4 moves upwards, the distance between the mold core 4 and the upper mold 3 is reduced, the volume of the cavity 5 is reduced, and if the mold core 4 moves downwards, the distance between the mold core 4 and the upper mold 3 is increased, and the volume of the cavity 5 is increased. After the volume of the cavity 5 is increased, the injection resistance is reduced, so that the molten plastic can be injected into the cavity 5 more quickly.

When the utility model is used, the lifting mechanism 8 is used for driving the lifting seat 7 and the mold core 4 to move downwards by a proper distance, so that the volume of the cavity 5 is increased, then molten plastic is injected into the cavity 5 through the injection port 6, and when the injection volume is the same as the volume of the lampshade, the injection is stopped. At this time, since the volume of the cavity 5 is larger than the volume of the injected molten plastic, the molten plastic cannot fill the cavity 5. Then, the lifting mechanism 8 is utilized to drive the lifting seat 7 and the mold core 4 to gradually move upwards, the volume of the mold cavity 5 is gradually reduced, the mold core 4 can extrude molten plastic in the mold cavity 5, the molten plastic is promoted to rapidly fill the whole mold cavity 5, and under the extrusion of the mold core 4, the molten plastic can be ensured to more uniformly fill the mold cavity 5, and further the thickness and the strength of the lampshade are ensured to be uniform.

Therefore, the utility model can reduce the resistance during injection, and simultaneously utilizes the mold core 4 to extrude the molten plastic, so that the molten plastic is promoted to quickly fill the cavity, the injection molding efficiency is improved, and the quality of the lampshade is ensured.

When demoulding, the upper mould 3 is required to be moved upwards to enable the upper mould 3 to be separated from the lower mould 2, manual separation can be adopted, and equipment such as a hydraulic cylinder and the like can be adopted to push the upper mould 3 to move up and down so as to realize automatic mould closing and mould separating. In order to ensure accurate butt joint of the upper die 3 and the lower die 2 during die assembly, a vertical guide post 9 is arranged on the die holder 1, and the guide post 9 penetrates through the upper die 3 and is in sliding fit with the upper die 3. The guide posts 9 play a role in guiding and positioning, ensure that the upper die 3 moves vertically up and down, and prevent the upper die 3 from horizontally shifting.

The mold core 4 moves upwards to have certain pressure when extruding molten plastic, in order to prevent the plastic in the mold cavity 5 from being discharged out of the mold cavity 5 through the injection molding opening 6, the detachable one-way valve 10 is arranged in the injection molding opening 6, the conduction direction of the one-way valve 10 is that the plastic is led into the mold cavity 5 from the outside of the mold cavity 5, the injection molding head of the injection molding machine can be butted with the one-way valve 10 when injecting, the molten plastic is injected into the mold cavity 5 through the one-way valve 10, and the plastic cannot be discharged through the one-way valve 10 when extruding the molten plastic by the mold core 4, so that the mold cavity 5 is fully filled with the plastic. The check valve 10 may be screwed to the injection port 6 or screwed to the upper mold 3 to facilitate removal of the check valve 10 and cleaning of the internally cured plastic.

In the present utility model, the lifting mechanism 8 is a hydraulic cylinder, and an apparatus such as an air cylinder may be used.

In the process of injecting molten plastic into the cavity 5 and extruding the molten plastic by the mold core 4, air in the cavity 5 needs to be discharged to reduce injection and extrusion resistance, and meanwhile, the defects of bubbles, holes and the like in the lamp shade are avoided. In order to exhaust air, an exhaust groove is arranged on the inner wall of the injection molding opening 6 or the parting surface of the lower die 2 and the upper die 3, and the exhaust groove can be arranged on the injection molding opening 6 and the parting surface at the same time, so that the exhaust effect is ensured. The width of the vent groove is usually 2 to 5mm, and the depth is about 0.02 to 0.04mm, which communicates the cavity 5 with the external space.

After the lampshade is formed, in order to promote rapid cooling and solidification of plastics, a cooling cavity 11 is arranged in the mold core 4, and the mold core 4 is made of heat conducting materials such as stainless steel and the like, so that heat can be rapidly delivered. The bottom surface of the lifting seat 7 is provided with a cooling medium inlet 12 and a cooling medium outlet 13 which are communicated with the cooling cavity 11, the cooling medium inlet 12 is connected with a cooling medium supply mechanism 15 through a first hose 14, and the cooling medium outlet 13 is connected with a second hose 16. The cooling medium supply means 15 can supply a cooling medium at a low temperature, which enters the cooling chamber 11 via the first hose 14 and the cooling medium inlet 12, cooling the mould core 4 and thus the plastic in the mould cavity 5. After absorbing heat, the cooling medium in the cooling chamber 11 is discharged from the cooling medium outlet 13 and the second hose 16.

In the present utility model, the cooling medium may be cool air outside the mold, the cooling medium supply mechanism 15 may be an air pump, and the second hose 16 may directly exhaust the air. In order to enhance the cooling effect, the cooling medium supply mechanism 15 includes a water tank in which cooling water is stored, the water tank being connected to the first hose 14 by a water pump 17, and the second hose 16 being connected to the water tank. Under the action of the water pump 17, cooling water in the water tank enters the cooling cavity 11 through the first hose 14 and the cooling medium inlet 12, absorbs heat and returns to the water tank through the second hose 16, so that recycling is realized. The water tank may be open to facilitate heat dissipation from the water in the water tank. The water level in the water tank can be monitored in real time, and cooling water can be timely supplemented when the water level is low.

After cooling, in order to facilitate demolding of the lampshade, an ejection mechanism can be arranged, as shown in fig. 2, a plurality of vertical ejection through holes are formed in the upper surface of the mold core 4, and the plurality of ejection through holes can be uniformly distributed around the center of the mold core 4 so as to ensure uniform stress of the lampshade during ejection. The upper portion of ejecting through-hole is provided with ejector pin 19 with ejecting through-hole sliding fit, and the fixed supporting shoe 20 that is provided with in lower part of ejecting through-hole, the upper surface of supporting shoe 20 and the lower surface contact of ejector pin 19. The shape of the upper surface of the ejector rod 19 is matched with the shape of the upper surface of the mold core 4, and when the lower surface of the ejector rod 19 contacts the upper surface of the supporting block 20, the shape of the upper surface of the ejector rod 19 and the upper surface of the mold core 4 form a molding surface matched with the inner wall of the lampshade. The support block 20 is provided with a medium through hole 21 communicating with the cooling chamber 11, and cooling water in the cooling chamber 11 can enter the medium through hole 21. The second hose 16 is provided with a valve 18, and after the valve 18 is closed, the cooling water in the cooling cavity 11 can be stopped from being discharged.

During injection of the molten plastic into the cavity 5 and extrusion of the molten plastic by the mold core 4, the lower surface of the ejector pins 19 contacts the upper surface of the support block 20. During cooling, the valve 18 is opened, and the cooling water in the cooling cavity 11 can be smoothly discharged. After cooling is finished, when demoulding is needed, the valve 18 can be closed, the water pressure in the cooling cavity 11 is increased, under the action of the water pressure, cooling water reaches the lower surface of the ejector rod 19 through the medium through hole 21, the water pressure is transmitted to the ejector rod 19, and the ejector rod 19 applies upward thrust to the lampshade, so that the lampshade is pushed to be separated from the mould core 4. After demoulding, the valve 18 is opened, the water pump 17 is closed, the water pressure in the cooling cavity 11 is reduced, and the ejector rod 19 moves downwards under the action of gravity until the lower end surface of the ejector rod contacts the supporting block 20.

The utility model uses cold water as demoulding power, does not need other power, simplifies the structure of the ejection mechanism, and reduces the manufacturing difficulty of the mould core 4.

The plastic lampshade injection molding device comprises a die assembly shown in fig. 1, and other parts of the injection molding device can adopt any one of the prior art.

The above description is only of the preferred embodiments of the present utility model and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims

1. The die assembly comprises a die holder (1), wherein a lower die (2) is fixedly arranged on the die holder (1), an upper die (3) is arranged above the lower die (2), a raised die core (4) is arranged on the upper surface of the lower die (2), a groove is arranged on the lower surface of the upper die (3), a cavity (5) is formed by surrounding the die core (4) and the groove, and an injection molding port (6) communicated with the cavity (5) is formed in the top of the upper die (3), and the die assembly is characterized in that:

The upper surface of lower mould (2) is provided with the constant head tank, be provided with in the constant head tank with constant head tank sliding fit's elevating platform (7), the upper end and the mold core (4) fixed connection of elevating platform (7), the lower extreme of elevating platform (7) is connected with elevating system (8).

2. The die assembly as claimed in claim 1, wherein the die holder (1) is provided with vertical guide posts (9), and the guide posts (9) penetrate through the upper die (3) and are in sliding fit with the upper die (3).

3. The mold assembly according to claim 1, wherein a detachable check valve (10) is provided in the injection port (6).

4. The mould assembly according to claim 1, characterized in that the lifting mechanism (8) is a hydraulic cylinder.

5. The die assembly as claimed in claim 1, wherein the inner wall of the injection port (6) or the parting surface of the lower die (2) and the upper die (3) is provided with an exhaust groove.

6. The mold assembly according to claim 1, wherein a cooling cavity (11) is arranged in the mold core (4), a cooling medium inlet (12) and a cooling medium outlet (13) which are communicated with the cooling cavity (11) are arranged on the bottom surface of the lifting seat (7), the cooling medium inlet (12) is connected with a cooling medium supply mechanism (15) through a first hose (14), and the cooling medium outlet (13) is connected with a second hose (16).

7. The mold assembly of claim 6, wherein the cooling medium supply means (15) comprises a water tank connected to the first hose (14) by a water pump (17), and the second hose (16) is connected to the water tank.

8. The mold assembly according to claim 7, wherein the valve (18) is arranged on the second hose (16), a plurality of vertical ejection through holes are arranged on the upper surface of the mold core (4), ejector rods (19) which are in sliding fit with the ejection through holes are arranged on the upper parts of the ejection through holes, supporting blocks (20) are fixedly arranged on the lower parts of the ejection through holes, the upper surfaces of the supporting blocks (20) are in contact with the lower surfaces of the ejector rods (19), and medium through holes (21) which are communicated with the cooling cavity (11) are arranged on the supporting blocks (20).

9. An injection molding device for a plastic lampshade, which is characterized by comprising the die assembly of claim 1.