CN111805849A

CN111805849A - Improved high-utilization-rate EVA (ethylene vinyl acetate) injection mold, double-color sole forming machine and process

Info

Publication number: CN111805849A
Application number: CN202010777339.8A
Authority: CN
Inventors: 林荣隆; 黄志敏
Original assignee: Fujian Quanzhou City Jialong Mould Co
Current assignee: Fujian Quanzhou City Jialong Mould Co
Priority date: 2020-08-05
Filing date: 2020-08-05
Publication date: 2020-10-23

Abstract

The invention discloses an improved EVA (ethylene vinyl acetate) injection mold with high utilization rate and a double-color sole forming machine and process, which comprise a mold body and a closed runner device which is detachably arranged on the mold body, wherein a plurality of mold cavities are formed on the mold body; the two ends of the hollow pipe are respectively connected with the connecting seat and the shunting seat, and the two ends of the hollow pipe are respectively communicated with the filling opening and the shunting flow passage. Compared with the prior art, the hollow pipe is arranged, so that the material in the runner can be used in the next injection molding process, and the utilization rate of the EVA material is improved. Compared with the mode of setting up the iron plate, the hollow tube has convenient maintenance, the convenient characteristics of processing, so reduce the cost of mould and improved production efficiency.

Description

Improved high-utilization-rate EVA (ethylene vinyl acetate) injection mold, double-color sole forming machine and process

Technical Field

The invention relates to the field of EVA (ethylene vinyl acetate) molding equipment, in particular to an improved EVA injection mold with high utilization rate, a double-color sole molding machine and a double-color sole molding process.

Background

As shown in fig. 1 and 2, in the conventional EVA injection mold, an EVA material is injected into a mold cavity 100 through a runner 200, and as the mold is separated, the EVA material in the runner 200 foams and expands due to air, and the EVA material of the next mold cannot be injected, and the EVA material after foaming in the runner 200 cannot be used and becomes EVA waste 300, which causes waste of raw materials. And the foamed EVA waste 300 in the runner 200 needs to be removed every time of mold separation, which occupies a large amount of labor cost.

As shown in fig. 3, the applicant has also developed a mold that covers the runner 200 with an iron block 400, so as to reduce the contact between the runner 200 and the air after opening the mold, so that the EVA material in the runner 200 can be injected into the final product in the next mold without foaming, thereby reducing the waste of raw materials. However, this method has a large space occupied by the iron blocks 400, and the manufacturing of the same size of the shoe sole increases the overall size of the mold. Because the matched size of the existing equipment for installing the mold is fixed, under the condition of the mold with the same external dimension, the mold with the iron block 400 can only produce soles with smaller code number, and the production efficiency is influenced.

With the improvement of living standard of people, consumers have more pursuits on the color and the style of shoes, and the traditional pure color sole can not meet the more pursuits of the consumers on the sole color.

In view of the above, the applicant has made an intensive study on the above-mentioned defects in the prior art, and has made this invention.

Disclosure of Invention

The invention mainly aims to provide an improved EVA (ethylene vinyl acetate) injection mold with high utilization rate, a double-color sole forming machine and a double-color sole forming process, which have the characteristics of improving the utilization rate of materials and the utilization rate of space in the mold.

In order to achieve the above purpose, the solution of the invention is:

an improved EVA (ethylene-vinyl acetate) injection mold with high utilization rate comprises a mold body and a closed runner device detachably mounted on the mold body, wherein a plurality of mold cavities are formed in the mold body, the closed runner device comprises a connecting seat, a hollow pipe and a shunting seat, an injection opening is formed in the connecting seat, shunting runners in one-to-one correspondence with the mold cavities are formed in the shunting seat, a plurality of dark runners communicated with the mold cavities one-to-one are formed in the mold body, and the shunting runners are communicated with the dark runners on the mold body; the two ends of the hollow pipe are respectively connected with the connecting seat and the shunting seat, and the two ends of the hollow pipe are respectively communicated with the filling opening and the shunting flow channel.

Furthermore, the die cavity comprises a first die cavity, a second die cavity, a third die cavity and a fourth die cavity, the shunting seat is positioned at the center of the surface of the die body, and the first die cavity, the second die cavity, the third die cavity and the fourth die cavity are distributed around the shunting seat; the length directions of the first die cavity, the second die cavity, the third die cavity and the fourth die cavity are all arranged along a first direction, and the hollow pipe is arranged along the first direction and is positioned on the die body between the first die cavity and the second die cavity.

Further, a first central line passing through the center of the die body and perpendicular to the first direction and a second central line passing through the center of the die body and parallel to the first direction are formed on the die body; the first die cavity and the second die cavity form a first die set, and the third die cavity and the fourth die cavity form a second die set; the first module and the second module are respectively positioned on two sides of the first central line; the first mold cavity and the second mold cavity are symmetrically arranged along a second central line, and the third mold cavity and the fourth mold cavity are symmetrically arranged along the second central line.

Further, arc-shaped yielding parts respectively corresponding to the first die cavity, the second die cavity, the third die cavity and the fourth die cavity are formed on the flow distribution seat.

Furthermore, the hollow pipe is a stainless steel pipe, and the outer diameter of the hollow pipe is 10-20 mm.

Further, the outer diameter of the hollow tube is 16 mm.

Furthermore, the end part of the hollow pipe extending into the flow distribution seat is provided with a reducing section, and one ends of the plurality of flow distribution channels are mutually communicated and are communicated with the reducing section.

Furthermore, a non-return device which is opened in one direction when the material is injected is arranged in the injection opening of the connecting seat.

A double-color sole forming machine comprises an upper die, a middle die and a lower die, wherein a first color die cavity is formed between the upper die and the middle die, and a second color die cavity is formed between the middle die and the lower die; the forming machine also comprises a first driving mechanism for driving the upper die, the middle die and the lower die to carry out die assembly action and a second driving mechanism for driving the middle die to reciprocate between the upper die and the lower die; the middle mold and/or the lower mold are/is the EVA injection mold.

A double-color sole molding process, wherein a double-color sole molding machine is used for injection molding, and the process comprises the following steps:

moving a middle die between an upper die and a lower die, closing the upper die, the middle die and the lower die, and respectively injecting a first color raw material and a second color raw material into a first color die cavity and a second color die cavity for heating and forming;

secondly, splitting the upper die, the middle die and the lower die; a first color forming body in the first color mold cavity is adhered to the upper mold, and a second color forming body in the second color mold cavity is adhered to the lower mold; removing the middle mold, closing the upper mold and the lower mold, and continuing heating to enable the first color forming body and the second color forming body to be attached to form a finished sole product;

and thirdly, separating the upper die from the lower die and taking down the finished product of the sole.

Further, the material injected into the first color mold cavity and/or the second color mold cavity is a mixture of at least two colors.

After adopting the structure, the improved EVA injection mold with high utilization rate, the double-color sole forming machine and the double-color sole forming process have the following beneficial effects:

one, through setting up the hollow tube, the EVA material is from the filling opening back of pouring into, enters into to dark runner through the reposition of redundant personnel runner in hollow tube and the reposition of redundant personnel seat, and then enters into to the die cavity in, the mould opens the back, and the EVA material in the hollow tube also can not contact the air to can inject to the die cavity when moulding plastics next time in, improve the utilization ratio of material, reduce the waste of material.

And secondly, the occupied width of the hollow pipe is smaller, and the occupied volume of the die body is reduced. So that the same size of the mold body can be provided with a larger size of the mold cavity or the same size of the mold cavity can be provided with a smaller size of the mold body. The production cost of the die is reduced, and the production efficiency is improved.

Thirdly, the hollow tube sets up and is located between two die cavitys along the length direction of die cavity for holistic structure is compacter, makes the die cavity design more nimble according to the size requirement, has improved the utilization ratio of mould body.

Fourthly, connecting seat, hollow tube and reposition of redundant personnel seat can be dismantled and be connected on the mould body, conveniently clear up the EVA material in the runner, even the hollow tube blocks up, also conveniently changes the hollow tube alone, has reduced the maintenance time of mould.

Compared with the prior art, the hollow pipe is arranged, so that the material in the runner can be used in the next injection molding process, and the utilization rate of the EVA material is improved. Compared with the mode of setting up the iron plate, the hollow tube has convenient maintenance, the convenient characteristics of processing, so reduce the cost of mould and improved production efficiency.

Drawings

Fig. 1 is a schematic structural diagram of a conventional EVA injection mold.

Fig. 2 is a schematic structural diagram of EVA waste in a conventional EVA injection mold.

Fig. 3 is a schematic structural view of a mold having an iron block.

Fig. 4 is a schematic top view of the present invention.

Fig. 5 is a schematic perspective view of the present invention.

Fig. 6 is a schematic view of the lower structure of the connecting seat, the hollow tube and the shunt seat.

Fig. 7 is a schematic perspective view of the cost of the double-color sole.

In the figure: a mold cavity 100; a flow passage 200; 300 parts of EVA waste; an iron block 400;

a mold body 1; a first mold cavity 11; a second mold cavity 12; a third mold cavity 13; a fourth mold cavity 14; a dark flow channel 15;

a closed flow channel device 2; a connecting base 21; an injection port 211; a hollow tube 22; a tapered section 221; a shunt seat 23; a flow dividing channel 231; an arc-shaped relief portion 232;

3, a finished sole product; a first color-formed body 31; and a second molded body 32.

Detailed Description

In order to further explain the technical solution of the present invention, the present invention is explained in detail by the following specific examples.

As shown in fig. 4 to 7, the improved high-utilization-rate EVA injection mold according to the present invention includes a mold body 1 and a closed runner device 2 detachably mounted on the mold body 1, the mold body 1 is formed with a plurality of mold cavities, the closed runner device 2 includes a connecting seat 21, a hollow tube 22 and a flow dividing seat 23, an injection port 211 is formed on the connecting seat 21, flow dividing runners 231 corresponding to the mold cavities one by one are formed on the flow dividing seat 23, a plurality of dark runners 15 communicating with the mold cavities one by one are formed in the mold body 1, and the flow dividing runners 231 communicate with the dark runners 15 on the mold body 1; two ends of the hollow tube 22 are respectively connected with the connecting seat 21 and the flow dividing seat 23, and two ends of the hollow tube 22 are respectively communicated with the injection port 211 and the flow dividing channel 231.

Thus, according to the improved high-utilization-rate EVA injection mold provided by the invention, due to the arrangement of the hollow tube 22, after being injected from the injection port 211, an EVA material enters the dark flow channel 15 through the hollow tube 22 and the flow dividing flow channel 231 in the flow dividing seat 23 and then enters the mold cavity, and after the mold is opened, the EVA material in the hollow tube 22 does not contact with air, so that the EVA material can be injected into the mold cavity in the next injection molding process, the utilization rate of the material is improved, and the waste of the material is reduced. Even if a small amount of EVA material foams at the position where the blind runner 15 is in contact with the mold cavity, the small amount of foamed EVA material can be contained in the sole when the EVA material is injected in the next mold closing process, and the injection molding cannot be affected.

The occupied width of the hollow tube 22 is small, and the occupied volume of the die body 1 is reduced. So that the same-sized mold body 1 can be provided with a larger-sized cavity or the same-sized mold cavity can be provided with a smaller-sized mold body 1. The production cost of the die is reduced, and the production efficiency is improved.

Preferably, the mold cavity includes a first mold cavity 11, a second mold cavity 12, a third mold cavity 13 and a fourth mold cavity 14, the flow dividing seat 23 is located at the center of the surface of the mold body 1, and the first mold cavity 11, the second mold cavity 12, the third mold cavity 13 and the fourth mold cavity 14 are distributed around the flow dividing seat 23; the hollow tube 22 is arranged in a first direction and is located on the mould body 1 between the first mould cavity 11 and the second mould cavity 12.

Preferably, the length directions of the first cavity 11, the second cavity 12, the third cavity 13 and the fourth cavity 14 are all arranged along a first direction, and a first central line passing through the center of the mold body 1 and perpendicular to the first direction and a second central line passing through the center of the mold body 1 and parallel to the first direction are formed on the mold body 1; the first die cavity 11 and the second die cavity 12 form a first die set, and the third die cavity 13 and the fourth die cavity 14 form a second die set; the first module and the second module are respectively positioned on two sides of the first central line; the first mold cavity 11 and the second mold cavity 12 are symmetrically arranged along a second central line, and the third mold cavity 13 and the fourth mold cavity 14 are symmetrically arranged along the second central line;

the hollow tube 22 is arranged along the length direction of the die cavity and is positioned between the two die cavities, so that the whole structure is more compact, the die cavity is designed more flexibly according to the size requirement, and the utilization rate of the die body 1 is improved.

Preferably, the shunting seat 23 is formed with arc-shaped relief portions 232 corresponding to the first mold cavity 11, the second mold cavity 12, the third mold cavity 13 and the fourth mold cavity 14, respectively. The arc-shaped position-giving part 232 reduces the area occupied by the flow dividing seat 23, so that the mold cavity can be better arranged on the mold body 1.

Preferably, the hollow tube 22 is a stainless steel tube, and the outer diameter of the hollow tube 22 is 10-20 mm. The hollow tube 22 is a round tube, and is convenient to purchase and process. Further, the hollow tube 22 has an outer diameter of 16 mm. Connecting seat 21, hollow tube 22 and reposition of redundant personnel seat 23 can be dismantled and connect on the mould body 1, conveniently clear up the EVA material in the runner, even hollow tube 22 blocks up, also conveniently changes hollow tube 22 alone, has reduced the maintenance time of mould.

Preferably, a tapered section 221 is formed at the end of the hollow tube 22 extending into the flow dividing seat 23, and one ends of the flow dividing channels 231 are communicated with each other and with the tapered section 221. The tapered section 221 is connected with the common end of the flow dividing flow channel 231 in the flow dividing seat 23, the flow velocity of the EVA material is improved through the tapered section 221, and the EVA material can conveniently enter the mold cavity.

Preferably, a check device (not shown) which is opened in one direction when the material is injected is arranged in the injection port 211 of the connecting seat 21. Thus, when the external spray gun does not inject the raw material into the injection port 211, the non-return device can automatically block the injection port 211.

The mould can be used for forming midsoles, slippers or other EVA products.

The invention also provides a double-color sole forming machine, which comprises an upper die, a middle die and a lower die, wherein a first color die cavity is formed between the upper die and the middle die, and a second color die cavity is formed between the middle die and the lower die; the forming machine also comprises a first driving mechanism for driving the upper die, the middle die and the lower die to carry out die assembly action and a second driving mechanism for driving the middle die to reciprocate between the upper die and the lower die; the middle mold and/or the lower mold are/is the EVA injection mold. The sole forming machine can be used for producing insole and slipper products.

The invention also provides a double-color sole molding process, which uses a double-color sole molding machine for injection molding and comprises the following steps: moving a middle die between an upper die and a lower die, closing the upper die, the middle die and the lower die, and respectively injecting a first color raw material and a second color raw material into a first color die cavity and a second color die cavity for heating and forming; secondly, splitting the upper die, the middle die and the lower die; the first color molded body 31 in the first color cavity is adhered to the upper mold, and the second color molded body 32 in the second color cavity is adhered to the lower mold; removing the middle mold, closing the upper mold and the lower mold, and continuing heating to enable the first color forming body 31 and the second color forming body 32 to be attached to form the finished sole product 3; and thirdly, separating the upper die from the lower die and taking down the finished sole product 3. Therefore, the first color forming body 31 and the second color forming body 32 can be connected with each other to form an integral structure in the injection molding process without glue, and the production efficiency is high.

Preferably, the material injected in the first color mold cavity and/or the second color mold cavity is a mixture of at least two colors. The upper part and/or the lower part of the finished sole 3 formed in this way are in a mixed color state, and a camouflage color sole can be produced.

Compared with the prior art, the hollow pipe 22 is arranged, so that the material in the runner can be used in the next injection molding process, and the utilization rate of the EVA material is improved. Compared with the mode of setting up the iron plate, hollow tube 22 has convenient maintenance, the convenient characteristics of processing, so reduce the cost of mould and improved production efficiency.

The above embodiments and drawings are not intended to limit the form and style of the present invention, and any suitable changes or modifications thereof by those skilled in the art should be considered as not departing from the scope of the present invention.

Claims

1. An improved EVA (ethylene-vinyl acetate) injection mold with high utilization rate is characterized by comprising a mold body and a closed runner device detachably mounted on the mold body, wherein a plurality of mold cavities are formed in the mold body, the closed runner device comprises a connecting seat, a hollow pipe and a shunting seat, an injection opening is formed in the connecting seat, shunting runners in one-to-one correspondence with the mold cavities are formed in the shunting seat, a plurality of dark runners communicated with the mold cavities one-to-one are formed in the mold body, and the shunting runners are communicated with the dark runners on the mold body; the two ends of the hollow pipe are respectively connected with the connecting seat and the shunting seat, and the two ends of the hollow pipe are respectively communicated with the filling opening and the shunting flow channel.

2. The improved high-utilization-rate EVA injection mold of claim 1, wherein the mold cavities comprise a first mold cavity, a second mold cavity, a third mold cavity and a fourth mold cavity, the shunting seat is located at the center of the surface of the mold body, and the first mold cavity, the second mold cavity, the third mold cavity and the fourth mold cavity are distributed around the shunting seat; the length directions of the first die cavity, the second die cavity, the third die cavity and the fourth die cavity are all arranged along a first direction, and the hollow pipe is arranged along the first direction and is positioned on the die body between the first die cavity and the second die cavity.

3. The improved high-utilization-rate EVA injection mold of claim 2, wherein the splitter seat has arc-shaped retainers corresponding to the first mold cavity, the second mold cavity, the third mold cavity and the fourth mold cavity, respectively.

4. The improved high-utilization-rate EVA injection mold of claim 2, wherein the mold body is formed with a first centerline passing through the center of the mold body and perpendicular to the first direction and a second centerline passing through the center of the mold body and parallel to the first direction; the first die cavity and the second die cavity form a first die set, and the third die cavity and the fourth die cavity form a second die set; the first module and the second module are respectively positioned on two sides of the first central line; the first mold cavity and the second mold cavity are symmetrically arranged along a second central line, and the third mold cavity and the fourth mold cavity are symmetrically arranged along the second central line.

5. The improved high-utilization-rate EVA injection mold of claim 1, wherein the hollow tube is a stainless steel tube and has an outer diameter of 10-20 mm.

6. The improved high-utilization-rate EVA injection mold of claim 1, wherein the end of the hollow pipe extending into the diversion seat is formed with a tapered section, and one ends of the diversion flow channels are communicated with each other and with the tapered section.

7. The improved high-utilization-rate EVA injection mold of claim 1, wherein a check device which is opened in one direction during material injection is arranged in the injection port of the connecting seat.

8. A double-color sole forming machine is characterized by comprising an upper die, a middle die and a lower die, wherein a first color die cavity is formed between the upper die and the middle die, and a second color die cavity is formed between the middle die and the lower die; the forming machine also comprises a first driving mechanism for driving the upper die, the middle die and the lower die to carry out die assembly action and a second driving mechanism for driving the middle die to reciprocate between the upper die and the lower die; the middle mold and/or the lower mold is the EVA injection mold according to any one of claims 1 to 7.

9. A process for molding a two-color shoe sole, characterized in that the injection molding is carried out by using the two-color shoe sole molding machine of claim 8, comprising the steps of:

10. A two-color shoe sole molding process according to claim 9, wherein the material injected into the first color cavity and/or the second color cavity is a mixture of at least two colors.