A plastic embryo blow molding device and process method

Abstract

The present invention discloses a plastic embryo blow molding device and process method, including a mold assembly and a blow molding assembly; the blow molding assembly is embedded in the center of the upper end surface of the mold assembly; the blow molding assembly includes a blow molding kit and a blow molding tube; the blow molding kit is arranged at the center of the upper end surface of the mold assembly, one end of the blow molding tube is arranged in the blow molding kit, and the other end is connected to the liquid nitrogen tank; the blow molding tube can spray liquid nitrogen or liquid nitrogen and air into the blow molding kit. In the mold closing and forming stage, the present invention injects liquid nitrogen in the form of mist or high-pressure liquid nitrogen into the blow molding kit, and the plastic embryo is formed through the spray hole of the blow molding kit. The characteristics of liquid nitrogen after gasification can be used to enhance the ductility of the plastic embryo, so that the plastic embryo fits the mold better and improves the smoothness, thereby enhancing the molding quality of the product; the low temperature of liquid nitrogen is used to quickly cool and solidify, and the molding and demolding are rapid, which greatly improves the production efficiency.

Description

Technical Field

[0001] The invention relates to the field of plastic embryo blow molding technology, and in particular to a plastic embryo blow molding device and a process method. Background Art

[0002] In the prior art, blow molding is usually carried out using a compressor. The air pressure of conventional blow molding equipment is 6-8KG. However, due to the insufficient pressure, the mold often cannot be well attached to the edge, which will cause the mold to have an unsightly molding appearance and poor surface smoothness. At the same time, especially for larger hollow plastic products, compared with the injection molding process, there are disadvantages such as low molding efficiency, weak strength, and large shrinkage. Summary of the invention

[0003] The purpose of the present invention is to provide a plastic embryo blow molding device, which is used to solve the problems of insufficient pressure in the blow molding process, unsightly mold molding, poor surface smoothness, low molding efficiency, etc.

[0004] The present invention solves the technical problem by adopting the following technical solution:

[0005] A plastic embryo blow molding device and process method, comprising a mold assembly and a blow molding assembly; the blow molding assembly is embedded in the center of the upper end surface of the mold assembly;

[0006] The blow molding assembly comprises a blow molding kit and a blow molding tube; the blow molding kit is arranged at the center of the upper end surface of the mold assembly, one end of the blow molding tube is arranged in the blow molding kit, and the other end is connected to the liquid nitrogen tank;

[0007] The blow molding tube can spray liquid nitrogen or liquid nitrogen and air into the blow molding kit.

[0008] Preferably, the blow molding kit is a hollow cylindrical structure, the upper end surface is provided with an opening, the lower end surface is a hemispherical structure protruding outward, and one end of the blow molding tube is inserted into the opening.

[0009] Preferably, a spray hole is provided at the bottom of the blow molding kit.

[0010] Preferably, the mold assembly includes a mold body and an inner cavity arranged in the mold body;

[0011] One end of the blow molding kit extends into the inner cavity from the center of the upper end surface of the mold body, and the other end is arranged outside the upper end surface of the mold body.

[0012] Preferably, the mold body includes a first mold and a second mold;

[0013] The first mold and the second mold have the same structure and are centrally symmetrically connected. The first mold and the second mold are hollow inside to form an inner cavity.

[0014] Preferably, a connecting groove is provided on the upper end surface of the mold body extending upward; the connecting groove is a circular ring structure, and the inner diameter of the connecting groove decreases from the top to the bottom;

[0015] The blow molding kit is arranged at the center of the connecting groove.

[0016] Preferably, a connecting hole is provided at the center of the upper end surface of the mold body; the connecting hole allows the blow molding kit to be arranged in the inner cavity.

[0017] Preferably, it also includes a blow molding connector; the blow molding connector is arranged on the upper end surface of the mold body and is matched and connected with the connecting groove;

[0018] The other end of the blow molding kit opposite to the inner cavity is arranged in the blow molding connector, and the blow molding tube passes through the blow molding connector to be connected with the liquid nitrogen tank.

[0019] Preferably, the blow-molded connector is a centrally symmetrical irregular rectangular parallelepiped structure, and the bottom side surfaces are symmetrically provided with slopes matching the connecting grooves.

[0020] Preferably, a receiving groove is recessed inwardly at the center of the bottom of the blow molding connector; the receiving groove can accommodate the blow molding kit.

[0021] Preferably, a plurality of rectangular grooves are symmetrically provided on both sides of the accommodating groove.

[0022] Preferably, the blow-molded connector is provided with a through hole, and the through hole can penetrate to the accommodating groove;

[0023] The blow molding tube can pass through the through hole in the containing tank and be connected to the liquid nitrogen tank.

[0024] Preferably, the blow molding tube is provided with a medium diffusion nozzle at one end of the blow molding kit;

[0025] The medium diffusion nozzle can spray liquid nitrogen into the blow molding kit.

[0026] Preferably, the medium diffusion nozzle is provided with a plurality of nozzle holes.

[0027] Preferably, a method for blow molding a plastic embryo is to connect the blow molding tube to a liquid nitrogen tank during the mold closing and molding stage, and directly inject air and atomized / high-pressure liquid nitrogen into the blow molding kit to quickly demold the mold.

[0028] Preferably, a method for blow molding a plastic embryo is used, in the mold closing and molding stage, the blow molding tube is connected to a liquid nitrogen tank, and atomized / high-pressure liquid nitrogen is sprayed into the blow molding kit through a medium diffusion nozzle for rapid molding and demolding.

[0029] The present invention has the following beneficial effects:.

[0030] 1) In the mold closing and molding stage, liquid nitrogen in the form of liquid mist or high-pressure liquid nitrogen is injected into the blow molding kit, and the plastic embryo is molded through the nozzle of the blow molding kit. The characteristics of liquid nitrogen after gasification can enhance the ductility of the plastic embryo, make the plastic embryo fit the mold better, improve the finish, and thus enhance the molding quality of the product;

[0031] 2) Use the low temperature of liquid nitrogen to quickly cool down and solidify, quickly form and demould, and greatly improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is the front view of the present invention;

[0033] Figure 2 It is a cross-sectional view of the present invention;

[0034] Figure 3 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0035] Figure 4 For the present invention Figure 3 A partial enlarged schematic diagram;

[0036] The markings in the figure are as follows: 1-mold assembly; 2-blow molding assembly; 3-blow molding kit; 4-blow molding tube; 5-opening; 6-nozzle; 7-mold body; 8-inner cavity; 9-first mold; 10-second mold; 11-connecting groove; 12-connecting hole; 13-blow molding connector; 14-slope; 15-accommodating groove; 16-rectangular groove; 17-through hole; 18-medium diffusion nozzle; 19-nozzle hole; 20-liquid nitrogen tank; 21-plastic embryo. DETAILED DESCRIPTION

[0037] The technical solution of the present invention is further described below in conjunction with the embodiments and drawings.

[0038] Example 1

[0039] This embodiment provides a preform blow molding device, comprising a mold assembly 1 and a blow molding assembly 2; the blow molding assembly 2 is embedded in the center of the upper end surface of the mold assembly 1;

[0040] The blow molding assembly 2 includes a blow molding kit 3 and a blow molding tube 4; the blow molding kit 3 is arranged at the center of the upper end surface of the mold assembly 1, one end of the blow molding tube 4 is arranged in the blow molding kit 3, and the other end is connected to the liquid nitrogen tank 20;

[0041] The blow molding tube 4 can spray liquid nitrogen or liquid nitrogen and air into the blow molding set 3 .

[0042] In view of the problems of insufficient pressure in the existing blow molding process, unsightly mold forming, poor surface smoothness, low molding efficiency, large shrinkage, etc., the present invention discloses a blow molding kit 3. In the blow molding process, the liquid nitrogen tank 20 sprays liquid nitrogen in the form of mist or high-pressure liquid nitrogen into the blow molding kit 3 through the blow molding tube 4. Through the characteristics of the atomized liquid nitrogen itself, not only the ductility of the plastic part is enhanced, but also the plastic part is made to fit the mold more closely, and the molding quality and smoothness of the product are enhanced.

[0043] In a further embodiment of the present invention, the blow molding kit 3 is a hollow cylindrical structure, the upper end surface of 3 is provided with an opening 5, the lower end surface is a hemispherical structure protruding outward, and one end of the blow molding tube 4 is inserted into the opening 5.

[0044] A spray hole 6 is provided at the bottom of the blow molding kit 3; the upper end opening of the blow molding kit 3 allows the blow molding tube 4 to be inserted, and only one spray hole 6 is left on the lower end surface for spraying liquid nitrogen, thereby forming a spray high pressure at the lower end of the blow molding kit 3 to ensure the strength of the internal pressure of the mold assembly 1.

[0045] According to a further embodiment of the present invention, the mold assembly 1 includes a mold body 7 and an inner cavity 8 arranged in the mold body 7; one end of the blow molding kit 3 extends into the inner cavity 8 from the center of the upper end surface of the mold body 7, and the other end is arranged outside the upper end surface of the mold body 7, and the plastic embryo 21 is arranged outside the blow molding kit 3 and extends into the inner cavity 8; the shape of the inner cavity 8 in the mold body 7 is the shape of the plastic part to be formed by the plastic embryo 21, and liquid nitrogen is sprayed into the blow molding kit 3 by the blow molding tube 4 and sprayed through the spray hole 6, so that the plastic embryo 21 forms the shape of the plastic part in the inner cavity 8, and the mold forming is completed.

[0046] In a further embodiment of the present invention, the mold body 7 includes a first mold 9 and a second mold 10;

[0047] The first mold 9 and the second mold 10 have the same structure and are centrally symmetrically connected. The first mold 9 and the second mold 10 are hollow inside to form an inner cavity 8. The first mold 9 and the second mold 10 are detachably connected to form a mold body 7, so that the plastic embryo 21 can be easily removed from the mold body 7 after molding.

[0048] In a further embodiment of the present invention, a connecting groove 11 is extended upward from the upper end surface of the mold body 7; the connecting groove 11 is a circular ring structure, and the inner diameter of the connecting groove 11 decreases from the top to the bottom; the connecting groove 11 is convenient for docking with the outside, and the blow molding kit 3 is arranged at the center of the connecting groove 11.

[0049] In a further embodiment of the present invention, a connecting hole 12 is provided at the center of the upper end surface of the mold body 7 ; the connecting hole 12 allows the blow molding kit 3 to be arranged in the inner cavity 8 , and the diameter of the connecting hole 12 is slightly larger than the diameter of the blow molding kit 3 .

[0050] A further embodiment of the present invention further comprises a blow molding connector 13; the blow molding connector 13 is disposed on the upper end surface of the mold body 7 and is cooperatively connected with the connecting groove 11;

[0051] The other end of the blow molding kit 3 opposite to the inner cavity 8 is arranged in the blow molding connector 13 , and the blow molding tube 4 passes through the blow molding connector 13 and is connected to the liquid nitrogen tank 20 .

[0052] like Figure 1 As shown, the blow molding connector 13 can be supported so that the liquid nitrogen tank 21 is arranged on the blow molding connector 13 , and the blow molding kit 3 is accommodated therein, thereby ensuring the sealing of the blow molding kit 3 .

[0053] According to a further implementation scheme of the present invention, the blow molding connector 13 is a centrally symmetrical irregular rectangular structure, the two sides of which can be separated for easy removal of the blow-molded plastic parts, and the plastic parts can also be removed by rotating the blow molding connector 13 without separation; the bottom side is symmetrically provided with a slope 14 that matches the connecting groove 11, and the slope 14 is fit-connected to the inner circle inner wall of the connecting groove 11 to achieve a tight connection with the mold body 7.

[0054] In a further embodiment of the present invention, a receiving groove 15 is recessed inwardly at the bottom center of the blow molding connector 13; the receiving groove 15 can accommodate the blow molding kit 3 therein, and the upper end of the blow molding kit 3 abuts against the receiving groove 15 to achieve an opening seal, thereby increasing the pressure of the liquid nitrogen sprayed in the blow molding kit 3.

[0055] In a further embodiment of the present invention, a plurality of rectangular grooves 16 are symmetrically provided on both sides of the receiving groove 15 .

[0056] In a further embodiment of the present invention, the blow molding connector 13 is provided with a through hole 17, and the through hole 17 can pass through the receiving groove 15. The through hole 17 is generally arranged on the upper end surface of the blow molding connector 13 to facilitate the insertion and connection of the blow molding tube 4 into the receiving groove 15; the blow molding tube 4 can pass through the through hole 17 from the receiving groove 15 to be connected to the liquid nitrogen tank 20.

[0057] Example 2

[0058] Since the temperature of liquid nitrogen is too low, direct contact with the preform 21 will cause the solidification rate of the preform 21 to be too fast, affecting the molding effect of the preform 21. This embodiment provides a preform blow molding device, which is different from the embodiment 1 only in that:

[0059] The blow molding tube 4 is provided with a medium diffusion nozzle 18 at one end of the blow molding kit 3; the medium diffusion nozzle 18 can spray liquid nitrogen into the blow molding kit 3, which not only has the function of spraying liquid nitrogen to allow the liquid nitrogen to fully volatilize and reduce the probability of liquid nitrogen directly contacting the plastic embryo, but also has a certain liquid storage function. The liquid nitrogen that is not vaporized in time can be formed into vaporized nitrogen by the injected liquid nitrogen, and then the plastic embryo is blow-molded by the blow molding kit 3, so that it will not directly contact the plastic embryo 21, so that the curing rate of the plastic embryo 21 is increased due to excessive cooling, which affects the molding effect of the plastic part 21. Through the built-in medium diffusion nozzle 18, the liquid nitrogen can be vaporized and pressurized to achieve the function of improving the product finish and rapid molding and demolding.

[0060] In a further embodiment of the present invention, the medium diffusion nozzle 18 is provided with a plurality of nozzle holes 19, and the nozzle holes 19 facilitate the liquid nitrogen to be sprayed out in a mist form.

[0061] Example 3

[0062] The present embodiment provides a method for blow molding a plastic embryo. In the mold closing and molding stage, the blow molding tube 4 is connected to the liquid nitrogen tank 20, and air and atomized / high-pressure liquid nitrogen are directly injected into the blow molding kit 3 to quickly demold the embryo.

[0063] Example 4

[0064] If only liquid nitrogen is used to form the plastic embryo 21, the blow molding effect of the plastic embryo 21 can be automatically achieved through its own weight or the gasification and pressurization phenomenon of the liquid nitrogen itself. The disadvantage is that the temperature of the liquid nitrogen may be too low and directly contact the plastic embryo 21, which will cause the plastic embryo 21 to solidify too quickly and affect the molding effect of the plastic embryo 21. This embodiment provides a plastic embryo blow molding process method. In the mold closing and molding stage, the blow molding tube 4 is connected to the liquid nitrogen tank 20, and atomized / high-pressure liquid nitrogen is sprayed into the blow molding kit 3 through the medium diffusion nozzle 18 for rapid molding and demolding.

[0065] The order of the above embodiments is only for the convenience of description and does not represent the advantages or disadvantages of the embodiments.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A plastic embryo blow molding device, It is characterized in that It includes a mold assembly and a blow molding assembly; the blow molding assembly is embedded in the center of the upper end surface of the mold assembly; The blow molding assembly comprises a blow molding kit and a blow molding tube; the blow molding kit is arranged at the center of the upper end surface of the mold assembly, one end of the blow molding tube is arranged in the blow molding kit, and the other end is connected to the liquid nitrogen tank; The blow molding tube can spray liquid nitrogen or liquid nitrogen and air into the blow molding kit; The blow molding kit is a hollow cylindrical structure, the upper end surface is provided with an opening, and the lower end surface is a hemispherical structure protruding outward; One end of the blow molding tube is inserted into the opening; The bottom of the blow molding kit is provided with a spray hole; The blow molding tube is provided with a medium diffusion nozzle at one end of the blow molding kit; The medium diffusion nozzle can spray liquid nitrogen into the blow molding kit; the medium diffusion nozzle has a certain liquid storage function; The medium diffusion nozzle is provided with a plurality of nozzle holes.

2. The preform blow molding device according to claim 1, It is characterized in that The mold assembly includes a mold body and an inner cavity arranged in the mold body; One end of the blow molding kit extends into the inner cavity from the center of the upper end surface of the mold body, and the other end is arranged outside the upper end surface of the mold body.

3. The preform blow molding device according to claim 2, It is characterized in that The mold body includes a first mold and a second mold; The first mold and the second mold have the same structure and are centrally symmetrically connected. The first mold and the second mold are hollow inside to form an inner cavity.

4. The preform blow molding device according to claim 3, It is characterized in that The upper end surface of the mold body is provided with a connecting groove extending upward; the connecting groove is a circular ring structure, and the inner diameter of the connecting groove decreases from the top to the bottom; The blow molding kit is arranged at the center of the connecting groove.

5. The preform blow molding device according to claim 2, It is characterized in that A connecting hole is provided at the center of the upper end surface of the mold body; the connecting hole allows the blow molding kit to be arranged in the inner cavity.

6. The preform blow molding device according to claim 4, It is characterized in that It also includes a blow molding connector; the blow molding connector is arranged on the upper end surface of the mold body and is matched and connected with the connecting groove; The other end of the blow molding kit opposite to the inner cavity is arranged in the blow molding connector, and the blow molding tube passes through the blow molding connector to be connected with the liquid nitrogen tank.

7. The preform blow molding device according to claim 6, It is characterized in that The blow-molded connector is a centrally symmetrical irregular rectangular parallelepiped structure, and the bottom side surfaces are symmetrically provided with slopes matching the connecting grooves.

8. The preform blow molding device according to claim 7, It is characterized in that A receiving groove is recessed inwardly at the center of the bottom of the blow molding connector; the receiving groove can accommodate the blow molding kit.

9. The preform blow molding device according to claim 8, It is characterized in that A plurality of rectangular grooves are symmetrically arranged on both sides of the accommodating groove.

10. The preform blow molding device according to claim 8, It is characterized in that The blow molding connector is provided with a through hole, and the through hole penetrates to the receiving groove; The blow molding tube passes through a through hole from the containing tank and is connected to the liquid nitrogen tank.

11. A preform blow molding process, based on the preform blow molding device according to any one of claims 1 to 10, It is characterized in that During the mold closing and molding stage, the blow molding tube is connected to the liquid nitrogen tank, and air and atomized / high-pressure liquid nitrogen are directly injected into the blow molding kit for rapid demoulding.

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