CN113263677B - Injection molding machine for polyamide composite material product and molding method thereof - Google Patents

Abstract

The invention provides an injection molding machine and a molding method for polyamide composite material products, and belongs to the technical field of injection molding equipment for polyamide composite material products. Solves the problem that the exhaust gas adversely affects the flow resistance of the ejection end. The technical proposal is as follows: the mold comprises a machine barrel arranged on a base and a mold connected with the machine barrel, wherein a screw is arranged in the machine barrel, the mold comprises a female mold connected with an injection end of the machine barrel and a male mold matched with the female mold to form a cavity, and one end of the male mold is provided with an oil cylinder pushing mechanism. The beneficial effects of the invention are as follows: according to the invention, the exhaust mechanism is arranged in the female die, so that a gelatinous raw material cannot enter the buffer cavity when the male die and the female die are matched, the original shape of the cavity can be ensured, and the molding effect of a product is ensured; and the female die and the machine barrel are connected with each other in a threaded manner and can be disassembled and replaced, and the male die can be disassembled and replaced as required, so that the equipment cost expenditure can be saved, the production efficiency is improved, and the practicability is very high.

Description

Injection molding machine for polyamide composite material product and molding method thereof

Technical Field

The invention relates to the technical field of polyamide composite material product injection molding equipment, in particular to a polyamide composite material product injection molding machine and a molding method thereof.

Background

In the process of mold closing and mold opening of a male mold and a female mold of a polyamide composite material product injection molding machine, poor air exhaust is an important factor influencing the flow resistance of a colloid polyamide composite material, whether the air exhaust of the mold is good or bad is closely related to the flow resistance of an injection end, when the mold is closed each time, although the interior of the male mold is empty, air is coated in, the raw material is compressed into the interior of the male mold after entering the mold, so that the internal pressure of a cavity is increased, the flow resistance is further increased, when the air exhaust of the mold is bad, the flow resistance of the injection end is rapidly increased, even the raw material generates high-temperature cracking and scorching at the end of a finished product due to excessive compressed hot air, the volume of the air in the mold is equal to the volume of the whole mold, so that the amount of air is discharged by the raw material, and when the air exhaust efficiency of the mold is better, the flow resistance during injection is lower, and the molding is easier;

and the injection molding machine in common use can only aim at one product, the die can not be replaced at will, and the single die has low utilization rate for factories with more product types.

How to solve the technical problems is the subject of the present invention.

Disclosure of Invention

The invention aims to provide an injection molding machine and a molding method for polyamide composite material products, which can avoid adverse influence of exhaust on the flow resistance of an injection terminal, ensure good molding effect, and can also change a mold, save cost and improve efficiency.

The invention is realized by the following measures: the injection molding machine for the polyamide composite material product comprises a machine barrel arranged on a base and a mold connected with the machine barrel, wherein a screw is arranged in the machine barrel, a hopper is arranged on the side wall of the top of the machine barrel and positioned at the initial end of the screw, the mold comprises a female mold connected with the injection end of the machine barrel and a male mold matched with the female mold to form a cavity, one end of the male mold far away from the female mold is provided with an oil cylinder pushing mechanism, and an exhaust mechanism is arranged in the female mold; the oil cylinder of the oil cylinder pushing mechanism pushes the male die to advance and retreat, the front end of the oil cylinder pushing mechanism is fixedly connected with the male die through a spring, and the ejector rod at the front end of the oil cylinder pushing mechanism ejects a product out of the male die when the female die of the male die is opened.

The connecting end of the machine barrel and the female die is an ejection end, the ejection end is arranged in a cylinder shape, and an external thread is arranged on the outer wall of the ejection end;

the female die comprises an outer die I fixedly arranged on a base and an inner die I movably sleeved in the outer die I, a threaded hole I matched with the outer wall of the ejection tail end is formed in the center of the inner die I, and a limit hole I which is symmetrical relative to the center of the inner die I is formed in the side surface of the inner die I, close to the male die;

the male die comprises an outer die II arranged at the front end of the oil cylinder propelling mechanism and an inner die II fixedly arranged at the middle part of one end of the outer die II towards the machine barrel, and the area formed by the outer part of the inner die II and the inner part of the inner die I is the cavity.

The first external mold is square, the first internal mold is circular, a circular groove matched with the first internal mold is formed in the center of the first external mold, the top of the first internal mold is provided with a vertical exhaust hole which sequentially penetrates through the first internal mold and the side wall of the first external mold, a buffer cavity is arranged in the middle section of the exhaust hole in the first internal mold, the upper part and the lower part of the buffer cavity are communicated with the exhaust hole, and the periphery of the buffer cavity is sealed.

The exhaust mechanism is located in the buffer cavity, the exhaust mechanism comprises a bottom plug arranged at the bottom and a top plug arranged right above the bottom plug, a vertical limiting rod is fixedly arranged at the top of the bottom plug, the center of the top plug is in sliding connection with the limiting rod, a spring is connected between the bottom plug and the top plug, and the spring is sleeved outside the limiting rod.

The top plug is in an upright conical shape, the top end diameter of the top plug is smaller than the diameter of the exhaust hole, and the bottom end diameter of the top plug is larger than the diameter of the exhaust hole;

the bottom plug is in an inverted cone shape, the top end diameter of the bottom plug is larger than the diameter of the exhaust hole, and the bottom end diameter of the bottom plug is smaller than the diameter of the exhaust hole; when the top plug presses the bottom plug downwards so that the bottom plug plugs the exhaust hole at the bottom of the buffer cavity, the bottom end of the bottom plug is flush with the bottom end of the exhaust hole;

the diameter of the limiting rod is smaller than that of the exhaust hole.

The torsion tool is matched with the first limiting hole of the first internal mold and comprises a hand grip and two torsion columns fixedly arranged on one side of the hand grip, and the torsion columns are matched with the first limiting hole.

The injection end of the screw is provided with a conical screw head, and the screw is driven by a screw motor.

The initial end of the screw rod is provided with a conical screw rod tail, and the conical screw rod tail and the tip end of the conical screw rod head face one end of the die.

The connecting groove is formed in the middle of one side of the second outer die, which faces the second inner die, a connecting plate matched with the connecting groove is fixedly arranged on one side of the second inner die, a plurality of second threaded holes are formed in one side of the connecting plate, which faces the connecting groove, of the second outer die, corresponding second threaded holes are formed in the connecting groove of the second outer die, and the second threaded holes of the connecting plate are fixedly connected with the second threaded holes of the second outer die through bolts.

The bottom plug is made of rubber material, and the top plug is made of metal material.

A molding method of an injection molding machine for polyamide composite material articles, comprising the steps of:

s1, determining the shape of a cavity according to the shape of a product to be produced, and manufacturing a first internal mold and a second internal mold;

s2, sleeving the first inner die into the first outer die, clamping a twisting column of a twisting tool in the first limiting hole, twisting a handle to enable the ejection tail end to be connected with the first inner die through threads, and enabling the exhaust holes on the side walls of the first inner die and the first outer die to correspond to each other in the vertical direction;

s3, fixedly connecting a threaded hole II on a connecting plate of the inner die II with a threaded hole II of the outer die II through bolts, wherein a region formed by the outer part of the inner die II and the inner part of the inner die I is a cavity;

s4, filling polyamide composite material particle raw materials into a hopper, enabling the raw materials to enter the initial end of a machine barrel, enabling a screw motor to drive a screw to rotate at a certain rotating speed, and conveying the raw materials to the injection end through threads by utilizing the rotation of the screw;

s5, in the advancing process of the raw materials, under the heating action of friction shearing generated by the rotation of a heating ring and a screw rod on a machine barrel and the raw materials, the generated high-temperature heat melts raw material particles into colloid;

s6, extruding the melted raw materials into a cavity of a die from the injection end by utilizing the thrust of a screw;

s7, because the bottom plug is made of rubber material, the top plug is made of metal material, when the exhaust mechanism is in an initial state, the top plug downwards presses the bottom plug under the action of gravity, so that the bottom plug blocks the exhaust hole at the bottom of the buffer cavity;

when the male die and the female die are matched, air is coated, the raw materials enter the die and compress the air in the die, so that the internal pressure of the die cavity is increased, when a certain pressure value is reached, the bottom plug is jacked up by the air pressure, and the elastic deformation acting force of the spring is added, so that the top plug is sprung up and plugs the vent hole at the top of the buffer cavity, when the buffer cavity is filled with air, the air pressure is continuously increased, the top plug keeps a state of plugging the vent hole, the gelatinous raw materials cannot enter the buffer cavity, and the original shape of the die cavity can be ensured;

s8, cooling and molding the gelatinous raw materials in a cavity, opening the die after shaping, and taking out the product after the ejector rod of the oil cylinder pushing mechanism ejects the product.

Compared with the prior art, the invention has the beneficial effects that: the invention provides an injection molding machine for polyamide composite material products and a molding method thereof, wherein an exhaust mechanism is arranged in a female die, so that a gelatinous raw material cannot enter a buffer cavity when the male die and the female die are assembled, the original shape of a cavity can be ensured, and the molding effect of a product is ensured; the female die and the machine barrel are connected with each other in a threaded mode, the male die can be detached and replaced according to the requirement, small-sized accessories such as metal parts can be added on the second inner die of the male die in advance, and then the small-sized accessories are mounted on the second outer die, so that the equipment cost expenditure can be saved, the production efficiency is improved, and the machine has very strong practicability.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate the invention and together with the embodiments of the invention, serve to explain the invention.

Fig. 1 is a schematic overall structure of an embodiment of the present invention.

FIG. 2 is a schematic view of the barrel structure of an embodiment of the present invention.

Fig. 3 is a schematic structural view of a screw according to an embodiment of the present invention.

Fig. 4 is a schematic structural view of a torsion tool according to an embodiment of the present invention.

FIG. 5 is a schematic diagram of a master mold according to an embodiment of the invention.

FIG. 6 is a longitudinal cross-sectional view of the first mold of the master mold according to an embodiment of the present invention.

FIG. 7 is a schematic diagram of an exhaust mechanism in an inner mold I according to an embodiment of the present invention.

Fig. 8 is a schematic structural diagram of a male die according to an embodiment of the invention.

Fig. 9 is a schematic structural diagram of a second outer mold of the male mold in embodiment 2 of the present invention.

Fig. 10 is a schematic diagram of a second internal mold of the male mold according to embodiment 2 of the present invention.

Wherein, the reference numerals are as follows: 1. a barrel; 101. an ejection end; 2. a screw; 201. a conical screw head; 202. a conical screw tail; 3. a hopper; 4. a screw motor; 5. a master mold; 501. an outer mold I; 502. an internal mold I; 503. a first threaded hole; 504. a first limiting hole; 6. a male mold; 601. an outer mold II; 602. an internal mold II; 8. a base; 9. an exhaust hole; 10. a buffer chamber; 11. a bottom plug; 12. a top plug; 13. a limit rod; 14. a spring; 15. a hand grip; 16. twisting the column; 17. a connecting groove; 18. a connecting plate; 19. and a threaded hole II.

Detailed Description

The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. Of course, the specific embodiments described herein are for purposes of illustration only and are not intended to limit the invention.

Example 1

Referring to fig. 1 to 8, the invention provides a technical scheme that an injection molding machine for polyamide composite material products comprises a machine barrel 1 arranged on a base 8 and a mold connected with the machine barrel 1, wherein a screw rod 2 is arranged in the machine barrel 1, a hopper 3 is arranged on the side wall of the top of the machine barrel 1 and at the initial end of the screw rod 2, the mold comprises a female mold 5 connected with the injection end of the machine barrel 1 and a male mold 6 matched with the female mold 5 to form a cavity, one end of the male mold 6 far away from the female mold 5 is provided with an oil cylinder pushing mechanism, and an exhaust mechanism is arranged in the female mold 5; the oil cylinder of the oil cylinder pushing mechanism pushes the male die 6 to advance and retreat, the front end of the oil cylinder pushing mechanism is fixedly connected with the male die 6 through a spring, and the ejector rod at the front end of the oil cylinder pushing mechanism ejects a product out of the male die 6 when the female die of the male die is opened.

The connecting end of the machine barrel 1 and the female die 5 is an ejection end 101, the ejection end 101 is arranged in a cylinder shape, and an external thread is arranged on the outer wall of the ejection end 101;

the female die 5 comprises an outer die I501 fixedly arranged on the base 8 and an inner die I502 movably sleeved in the outer die I501, a threaded hole I503 matched with the outer wall of the injection end 101 is formed in the center of the inner die I502, and a limiting hole I504 symmetrical to the center of the inner die I502 is formed in the side surface, close to the male die 6, of the inner die I502;

the male die 6 comprises an outer die II 601 arranged at the front end of the oil cylinder propelling mechanism and an inner die II 602 fixedly arranged at the middle part of one end of the outer die II 601 facing the machine barrel 1, wherein the area formed by the outer part of the inner die II 602 and the inner part of the inner die I502 is a cavity.

The first outer mold 501 is square, the first inner mold 502 is circular, a circular groove matched with the first inner mold 502 is formed in the center of the first outer mold 501, the top of the first inner mold 502 is provided with a vertical exhaust hole 9 which sequentially penetrates through the side walls of the first inner mold 502 and the first outer mold 501, a buffer cavity 10 is arranged in the middle section of the exhaust hole 9 on the first inner mold 502, the upper part and the lower part of the buffer cavity 10 are communicated with the exhaust hole 9, and the periphery of the buffer cavity 10 is sealed.

The exhaust mechanism is located the cushion chamber 10, and exhaust mechanism is including setting up the bottom stopper 11 in the bottom and setting up the top stopper 12 directly over the bottom stopper 11, and the top of bottom stopper 11 is fixed to be provided with vertical gag lever post 13, and the center and the gag lever post 13 sliding connection of top stopper 12 are connected with spring 14 between bottom stopper 11 and the top stopper 12, and spring 14 cup joints in gag lever post 13 outside.

The top plug 12 is in an upright cone shape, the top end diameter of the top plug 12 is smaller than the diameter of the exhaust hole 9, and the bottom end diameter of the top plug 12 is larger than the diameter of the exhaust hole 9;

the bottom plug 11 is in an inverted cone shape, the top end diameter of the bottom plug 11 is larger than the diameter of the exhaust hole 9, and the bottom end diameter of the bottom plug 11 is smaller than the diameter of the exhaust hole 9; when the top stopper 12 presses down the bottom stopper 11 so that the bottom stopper 11 blocks the exhaust hole 9 at the bottom of the buffer chamber 10, the bottom end of the bottom stopper 11 is flush with the bottom end of the exhaust hole 9;

the diameter of the limit rod 13 is smaller than that of the exhaust hole 9.

A twisting tool is arranged in cooperation with the first limiting hole 504 of the first inner mold 502, and comprises a hand grip 15 and two twisting columns 16 fixedly arranged on one side of the hand grip 15, wherein the twisting columns 16 are matched with the first limiting hole 504.

The injection end of the screw 2 is provided as a conical screw head 201, the screw 2 being driven by a screw motor 4.

The initial end of the screw 2 is provided with a conical screw tail 202, and the tips of the conical screw tail 202 and the conical screw head 201 face one end of the die.

The middle part of one side of the second outer die 601 facing the second inner die 602 is provided with a connecting groove 17, one side of the second inner die 602 is fixedly provided with a connecting plate 18 matched with the connecting groove 17, one side of the connecting plate 18 facing the connecting groove 17 is provided with a plurality of second threaded holes 19, the connecting groove of the second outer die 601 is internally provided with a corresponding second threaded hole 19, and the second threaded holes 19 of the connecting plate 18 are fixedly connected with the second threaded holes 19 of the second outer die 601 through bolts.

The bottom plug 11 is made of a rubber material, and the top plug 12 is made of a metal material.

A molding method of an injection molding machine for polyamide composite material articles, comprising the steps of:

s1, determining the shape of a cavity according to the shape of a product to be produced, and manufacturing a first internal mold 502 and a second internal mold 602;

s2, sleeving the first inner die 502 in the first outer die 501, clamping a twisting column 16 of a twisting tool in the first limiting hole 504, twisting the hand grip 15 to enable the injection end 101 to be in threaded connection with the first inner die 502, and enabling the exhaust holes 9 on the side walls of the first inner die 502 and the first outer die 501 to correspond in the vertical direction;

s3, fixedly connecting a threaded hole II 19 on a connecting plate 18 of the inner die II 602 with a threaded hole II 19 of the outer die II 601 through bolts, wherein a region formed between the outer part of the inner die II 602 and the inner part of the inner die I502 is a cavity;

s4, filling a hopper 3 with polyamide composite material particle raw materials, wherein the raw materials enter the initial end of a machine barrel 1, a screw motor 4 drives a screw 2 to rotate at a certain rotating speed, and the raw materials are conveyed to an injection terminal 101 by threads by utilizing the rotation of the screw 2;

s5, in the advancing process of the raw materials, under the heating action of friction shearing generated by the rotation of a heating ring and a screw rod 2 on a machine barrel 1 and the raw materials, the generated high-temperature heat melts raw material particles into colloid;

s6, extruding the melted raw materials into a cavity of a die from an injection terminal 101 by utilizing the thrust of a screw 2;

s7, as the bottom plug 11 is made of rubber material, the top plug 12 is made of metal material, when the exhaust mechanism is in an initial state, the top plug 12 presses the bottom plug 11 downwards under the action of gravity without the action of air pressure, so that the bottom plug 11 plugs the exhaust hole 9 at the bottom of the buffer cavity 10;

when the male die 6 and the female die 5 are matched, air is coated, the raw materials enter the die and compress the air in the die, so that the internal pressure of the die cavity is increased, when a certain pressure value is reached, the bottom plug 11 is jacked by the air pressure, the exhaust hole 9 at the top of the buffer cavity 10 is blocked by the top plug 12 due to the elastic deformation acting force of the spring 14, when the buffer cavity 10 is filled with air, the air pressure is continuously increased, the top plug 12 keeps the state of blocking the exhaust hole 9, the colloidal raw materials cannot enter the buffer cavity 10, and the original shape of the die cavity can be ensured;

s8, cooling and molding the gelatinous raw materials in a cavity, opening the die after shaping, and taking out the product after the ejector rod of the oil cylinder pushing mechanism ejects the product.

Example 2

Referring to fig. 9 to 10, on the basis of embodiment 1, a connecting groove 17 is formed in the middle of one side of the second outer mold 601 facing the second inner mold 602, a connecting plate 18 matched with the connecting groove 17 is fixedly arranged on one side of the second inner mold 602, a plurality of second threaded holes 19 are formed in one side of the connecting plate 18 facing the connecting groove 17, corresponding second threaded holes 19 are formed in the connecting groove of the second outer mold 601, and the second threaded holes 19 of the connecting plate 18 are fixedly connected with the second threaded holes 19 of the second outer mold 601 through bolts.

The foregoing description of the preferred embodiments of the invention is not intended to limit the invention to the precise form disclosed, and any such modifications, equivalents, and alternatives falling within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims (1)

1. The injection molding machine for the polyamide composite material product is characterized by comprising a machine barrel (1) arranged on a base (8) and a mold connected with the machine barrel (1), wherein a screw rod (2) is arranged in the machine barrel (1), a hopper (3) is arranged on the side wall of the top of the machine barrel (1) and positioned at the initial end of the screw rod (2), the mold comprises a female mold (5) connected with the injection end of the machine barrel (1) and a male mold (6) matched with the female mold (5) to form a cavity, one end, far away from the female mold (5), of the male mold (6) is provided with an oil cylinder propelling mechanism, and an exhaust mechanism is arranged in the female mold (5);

the connecting end of the machine barrel (1) and the female die (5) is an ejection tail end (101), the ejection tail end (101) is arranged in a cylinder shape, and an external thread is arranged on the outer wall of the ejection tail end (101);

the female die (5) comprises an outer die I (501) fixedly arranged on a base (8) and an inner die I (502) movably sleeved in the outer die I (501), a threaded hole I (503) matched with the outer wall of the injection tail end (101) is formed in the center of the inner die I (502), and a limiting hole I (504) symmetrical to the center of the inner die I (502) is formed in the side surface, close to the male die (6), of the inner die I (502);

the male die (6) comprises an outer die II (601) arranged at the front end of the oil cylinder propelling mechanism and an inner die II (602) fixedly arranged at the middle part of one end of the outer die II (601) towards the machine barrel (1), wherein a region formed by the outer part of the inner die II (602) and the inner part of the inner die I (502) is the cavity;

the first outer die (501) is square, the first inner die (502) is circular, a circular groove matched with the first inner die (502) is formed in the center of the first outer die (501), exhaust holes (9) which vertically penetrate through the side walls of the first inner die (502) and the first outer die (501) in sequence are formed in the top of the first inner die (502), a buffer cavity (10) is formed in the middle section of each exhaust hole (9) on the first inner die (502), the upper portion and the lower portion of each buffer cavity (10) are communicated with the corresponding exhaust holes (9), and the periphery of each buffer cavity (10) is sealed;

the exhaust mechanism is positioned in the buffer cavity (10), the exhaust mechanism comprises a bottom plug (11) arranged at the bottom and a top plug (12) arranged right above the bottom plug (11), a vertical limiting rod (13) is fixedly arranged at the top of the bottom plug (11), the center of the top plug (12) is in sliding connection with the limiting rod (13), a spring (14) is connected between the bottom plug (11) and the top plug (12), and the spring (14) is sleeved outside the limiting rod (13);

the top plug (12) is in an upright cone shape, the top end diameter of the top plug (12) is smaller than the diameter of the exhaust hole (9), and the bottom end diameter of the top plug (12) is larger than the diameter of the exhaust hole (9);

the bottom plug (11) is in an inverted cone shape, the top end diameter of the bottom plug (11) is larger than the diameter of the exhaust hole (9), and the bottom end diameter of the bottom plug (11) is smaller than the diameter of the exhaust hole (9); when the top plug (12) presses the bottom plug (11) downwards so that the bottom plug (11) plugs the exhaust hole (9) at the bottom of the buffer cavity (10), the bottom end of the bottom plug (11) is level with the bottom end of the exhaust hole (9);

the diameter of the limiting rod (13) is smaller than that of the exhaust hole (9);

a torsion tool is arranged in cooperation with a first limit hole (504) of the first inner die (502), the torsion tool comprises a hand grip (15) and two torsion columns (16) fixedly arranged on one side of the hand grip (15), and the torsion columns (16) are used in cooperation with the first limit hole (504);

the injection end of the screw (2) is provided with a conical screw head (201), and the screw (2) is driven by a screw motor (4);

the initial end of the screw (2) is provided with a conical screw tail (202), and the tips of the conical screw tail (202) and the conical screw head (201) face one end of the die;

a connecting groove (17) is formed in the middle of one side, facing the inner mold II (602), of the outer mold II (601), a connecting plate (18) matched with the connecting groove (17) is fixedly arranged on one side of the inner mold II (602), a plurality of threaded holes II (19) are formed in one side, facing the connecting groove (17), of the connecting plate (18), corresponding threaded holes II (19) are formed in the connecting groove of the outer mold II (601), and the threaded holes II (19) of the connecting plate (18) are fixedly connected with the threaded holes II (19) of the outer mold II (601) through bolts;

the bottom plug (11) is made of a rubber material, and the top plug (12) is made of a metal material;

a molding method of an injection molding machine for polyamide composite material articles, comprising the steps of:

s1, determining the shape of a cavity according to the shape of a product to be produced, and manufacturing a first internal mold (502) and a second internal mold (602);

s2, sleeving the first inner die (502) in the first outer die (501), clamping a twisting column (16) of a twisting tool in the first limiting hole (504), twisting a hand grip (15) to enable the injection tail end (101) to be in threaded connection with the first inner die (502), and enabling the first inner die (502) to correspond to an exhaust hole (9) on the side wall of the first outer die (501) in the vertical direction;

s3, fixedly connecting a threaded hole II (19) on a connecting plate (18) of the inner die II (602) with a threaded hole II (19) of the outer die II (601) through bolts, wherein a region formed by the outer part of the inner die II (602) and the inner part of the inner die I (502) is a cavity;

s4, filling a hopper (3) with polyamide composite material and polyamide composite material particle raw materials, enabling the raw materials to enter the initial end of a machine barrel (1), enabling a screw motor (4) to drive a screw (2) to rotate at a certain rotating speed, and conveying the raw materials to an injection terminal (101) through threads by utilizing the rotation of the screw (2);

s5, in the advancing process of the raw materials, under the heating action of friction shearing generated by the rotation of a heating ring and a screw (2) on a machine barrel (1) and the raw materials, the generated high-temperature heat melts raw material particles into colloid;

s6, extruding the melted raw materials into a cavity of a die from an injection end (101) by utilizing the thrust of a screw (2);

s7, as the bottom plug (11) is made of rubber materials, the top plug (12) is made of metal materials, when the exhaust mechanism is in an initial state, the top plug (12) presses the bottom plug (11) downwards under the action of gravity without the action of air pressure, so that the bottom plug (11) blocks the exhaust hole (9) at the bottom of the buffer cavity (10);

when the male die (6) and the female die (5) are closed, air is coated, the raw materials enter the die and then compress the air in the die, so that the internal pressure of the die cavity is increased, when a certain pressure value is reached, the air pressure jacks up the bottom plug (11), the elastic deformation acting force of the spring (14) is added, the top plug (12) is enabled to jack up and block the vent hole (9) at the top of the buffer cavity (10), when the buffer cavity (10) is filled with air, the air pressure is continuously increased, the top plug (12) keeps the state of blocking the vent hole (9), the gelatinous raw materials cannot enter the buffer cavity (10), and the original shape of the die cavity can be ensured;

s8, cooling and molding the gelatinous raw materials in a cavity, opening the die after shaping, and taking out the product after the ejector rod of the oil cylinder pushing mechanism ejects the product.

Images