TWI690406B - Pressure control molding method for accurately controlling foam size - Google Patents

Abstract

A pressure-control molding method for accurately controlling the size of a foam includes the following steps: (A) preparing a molding device, (B) placing a foaming material in a cavity formed by closing an upper and lower mold, and a cover Cover a first gas hood and evacuate, (C) cross-link the foamed raw material contained in the cavity, and foam into a foam, (D) break the vacuum and lift the first gas hood upward Remove the upper and lower molds, and then move the upper mold upwards away from the lower mold, (E) use a conveying unit to move the foam from the forming unit to a cooling tank of the cooling and setting unit, (F) A second air hood moves down to cover the container, and then a positive pressure is applied to cool and shape the foam under a positive pressure environment. (G) Move away from the second air hood and take out the cooled and shaped Foam.

Description

Pressure control molding method for accurately controlling foam size

The invention relates to a foam molding method, in particular to a pressure control molding method for precisely controlling the size of the foam.

The conventional EVA foam sole manufacturing process is generally to inject EVA plastic into the cavity of a foam mold, and then heat the foam mold to crosslink and foam the EVA plastic located in the cavity into a foam initial embryo, and then Take out the foaming embryo and cool and shape it in an uncontrolled pressure environment. Because the external atmospheric pressure will change with many factors, the external atmospheric pressure will affect the volume of the foaming embryo after shaping. When the atmospheric pressure is small, the expansion of the foaming embryo is larger during cooling. When the external atmospheric pressure is larger, the expansion of the foaming embryo is smaller during cooling, so the foam after shrinking and shaping The initial embryos may vary in size.

Then, select the foamed embryos that meet the size standards and place them in the first and second compression molding molds to perform the second compression molding process to form the outer pattern of the sole. After molding, take them out and also in an uncontrolled pressure environment. Cooling and shaping at room temperature or temperature control conditions, but the finished product will still be affected by the change of external atmospheric pressure, resulting in inconsistent dimensions. In this way, from the initial foaming to the completion of the finished product, there will be many defective products. It causes a loss of yield, and the traditional EVA foam sole process requires two foaming steps, and the process time is also longer.

Therefore, the purpose of the present invention is to provide an EVA foam sole method that requires only one foaming, and the foaming and shaping are in a pressure-controlled environment, so that the process speed is faster and the yield is better.

Therefore, the pressure control molding method for accurately controlling the size of the foam of the present invention includes the following steps:

(A) Prepare a molding device including a chamber, a molding unit provided in the chamber, a cooling sizing unit provided in the chamber, and a conveying unit provided in the chamber, the molding The unit has a first bottom plate, a lower mold disposed on the first bottom plate, an upper mold disposed above the lower mold and movable in a height direction, and a first gas hood movable in the height direction, The cooling sizing unit has a second bottom plate, a receiving groove provided on the second bottom plate, and a second air cover movable along the height direction.

(B) Place a foamed raw material in the cavity formed by the closing of the upper and lower molds, the first gas hood moves down along the height direction to close to the first bottom plate and cover the upper and lower molds , The space defined by the first gas hood and the first bottom plate is evacuated to reach a predetermined vacuum degree.

(C) Heating the upper and lower molds to cross-link and expand the foamed raw materials contained in the mold cavity into a foamed product.

(D) Break the vacuum and move the first gas hood upward away from the first bottom plate and the upper and lower molds, and then move the upper mold upward away from the lower mold.

(E) The conveying unit moves the foam from the molding unit to the cooling tank of the cooling and setting unit.

(F) The second gas hood moves down along the height direction to close to the second bottom plate and cover the receiving groove, and then apply a positive pressure to the space defined by the second gas hood and the second bottom plate So that the foam is cooled and shaped under a positive pressure environment.

(G) Move away from the second gas hood and take out the foam that has been cooled and set.

The effect of the present invention is that after the foaming raw material is foamed into foam by using the molding unit, the foam is cooled and shaped by the cooling and shaping unit. The present invention only needs one foaming step, compared with the traditional one. The EVA foam sole process, the invention can shorten the process time, in addition, the invention is carried out under a pressure-controlled environment regardless of the foaming process or the cooling and shaping process, so the finished product will not be affected by changes in the external atmospheric pressure The size of the foam is consistent, in addition, the positive pressure applied during cooling and setting can be adjusted to control the size of the final product.

As shown in FIG. 1, an embodiment of the pressure control molding method for accurately controlling the size of the foam of the present invention includes the following steps:

Step S100: With reference to FIG. 2, a molding device 1 is prepared. The molding device 1 includes a chamber 11, a molding unit 12 disposed in the chamber 11, a cooling sizing unit 13 disposed in the chamber 11, and A conveying unit 14 disposed in the chamber 11, the molding unit 12 has a first bottom plate 121, a lower mold 122 disposed on the first bottom plate 121, and a lower mold 122 disposed above and along a height direction The upper mold 123 moved by H, and a first air cover 124 movable along the height direction H, the cooling sizing unit 13 has a second bottom plate 131, a receiving groove 132 provided in the second bottom plate 131, a setting An upper platen device 133 above the receiving groove 132 and movable in the height direction H, and a second air hood 134 movable in the height direction H, the conveying unit 14 has a sliding device 141, and a The sliding device 141 can move along the height direction H of the fixing device 142.

Step S200: With reference to FIG. 3, place a foamed material 2 in the cavity 125 formed by closing the upper and lower molds 123, 122, and the cavity 125 formed by closing the upper and lower molds 123, 122 The wall has a plastic pattern 126, and the first air cover 124 moves down along the height direction H to close to the first bottom plate 121 and covers the upper and lower molds 123, 122, and then the first air cover 124 and The space defined by the first bottom plate 121 is evacuated to achieve a predetermined vacuum degree.

Step S300: Referring to FIG. 4, heating the upper and lower molds 123 and 122 to cross-link and foam-form the foamed raw material 2 contained in the cavity 125 into a foamed product 3.

Step S400: Referring to FIG. 5, the vacuum is broken and the first gas hood 124 is moved upward away from the first bottom plate 121 and the upper and lower molds 123, 122, and then the upper mold 123 is moved upward away from the lower mold 122.

Step S500: With reference to FIGS. 5 and 6, the conveying unit 14 is used to move the foam 3 from the forming unit 12 to the cooling tank 132 of the cooling sizing unit 13. First, the sliding device 141 moves the fixing device 142 After reaching above the lower mold 122, in this embodiment, the bottom of the fixing device 142 is provided with a plurality of suction cups 143, and the fixing device 142 moves down along the height direction H and absorbs the foam through the suction cups 143 3, and then move upward, and then the sliding device 141 moves to the upper side of the container 132 again, and releases the adsorption of the foam 3, so that the foam 3 falls into the container 132, the container 132 contains There is cooling water 4. During the movement, the chamber 11 is in a certain pressure environment.

Step S600: With reference to FIG. 7, the upper platen device 133 moves downward along the height direction H, and presses down the foam 3 to completely submerge it into the cooling water 4.

Step S700: Referring to FIG. 7, the second gas cover 134 moves down along the height direction H to close to the second bottom plate 131 and cover the receiving groove 132, and then the second gas cover 134 and the second A positive pressure is applied to the space defined by the bottom plate 131 to cool and shape the foam 3 under a positive pressure environment, and the cooling temperature is less than 22°C.

Step S800: Referring to FIG. 8, the second air hood 134 and the upper platen device 133 are removed, and the foam 3 cooled and shaped is taken out.

With reference to FIG. 9, the foam 3 is a sole having a sculpt pattern 126 of the mold cavity 125 that meets the size.

Through the above description, the advantages of the present invention can be summarized as follows:

1. After the foaming raw material 2 is foamed into the foamed material 3 by the molding unit 12, the foamed material 3 is cooled and shaped by the cooling and shaping unit 13, the present invention only needs one foaming step, compared with the traditional The manufacturing process of the EVA foam sole requires two foaming steps, and the invention can effectively shorten the manufacturing time.

2. The present invention is carried out under a pressure-controlled environment regardless of the foaming process, conveying process and cooling setting process, so the finished product will not be affected by the change of the external atmospheric pressure, and the size of the finished foam product can be made consistent. Compared with the traditional EVA foamed sole manufacturing process, it is affected by the change of external atmospheric pressure, so that the size of the foamed sole varies to affect the yield. The yield of the present invention is better, and there is almost no yield loss due to the size difference. .

3. The present invention can accurately control the final size of the final foam product by adjusting the positive pressure applied during cooling and shaping.

4. The present invention uses water cooling to cool the shaped foam. Compared with the traditional EVA foam sole process, it is cooled at room temperature in the air, or the temperature is controlled by a tunnel oven. The cooling rate of the present invention Faster, can also shorten the process time.

In summary, the pressure-control forming method of the present invention for precisely controlling the size of the foam not only has a faster process speed, a better yield, but also can accurately control the size of the finished product of the foam, so it can indeed achieve the purpose of the invention.

However, the above are only examples of the present invention, and should not be used to limit the scope of the present invention. Any simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the patent specification are still classified as This invention covers the patent.

1‧‧‧Molding device 11‧‧‧Room 12‧‧‧Molding unit 121‧‧‧First bottom plate 122‧‧‧Lower mold 123‧‧‧Upper mold 124‧‧‧First air cover 125‧‧‧ Cavity 126‧‧‧Plastic pattern 13‧‧‧cooling and shaping unit 131‧‧‧second bottom plate 132‧‧‧slot 133‧‧‧upper platen device 134‧‧‧second air cover 14‧‧‧transport unit 141 ‧‧‧Sliding device 142‧‧‧Fixing device 143‧‧‧Sucker 2‧‧‧Foam material 3‧‧‧Foam 4‧‧‧Cooling water H‧‧‧Height direction S100‧‧‧Step S200‧‧ ‧Step S300‧‧‧step S400‧‧‧step S500‧‧‧step S600‧‧‧step S700‧‧‧step S800‧‧‧step

Other features and functions of the present invention will be clearly presented in the embodiment with reference to the drawings, in which: FIG. 1 is a flow chart of an embodiment of the pressure control molding method for accurately controlling the size of the foam of the present invention　 FIG. 2 is a schematic diagram of an operation of a molding device used in the embodiment (1); 　 FIG. 3 is a schematic diagram of an operation of the molding device (2); 　 FIG. 4 is a schematic diagram of the operation of the molding device (3); 　5 is a schematic diagram of the operation of the molding device (four); 　 6 is a schematic diagram of the operation of the molding device (five); 　 Figure 7 is a schematic diagram of the operation of the molding device (six); 　 Figure 8 is an action of the molding device Schematic diagram (7); and FIG. 9 is a perspective view of a shoe sole made in this embodiment.

S100‧‧‧Step

S200‧‧‧Step

S300‧‧‧Step

S400‧‧‧Step

S500‧‧‧Step

S600‧‧‧Step

S700‧‧‧Step

S800‧‧‧Step

Claims (3)

A pressure-controlling molding method for accurately controlling the size of a foamed material includes the following steps: (A) preparing a molding device including a chamber, a molding unit disposed in the chamber, and a molding chamber Cooling and sizing unit of the chamber, and a conveying unit provided in the chamber, the chamber is in a certain pressure environment, the molding unit has a first bottom plate, a lower mold provided on the first bottom plate, and a lower plate An upper mold that can move along a height direction above the mold, and a first gas hood that can move along the height direction, the cooling sizing unit has a second bottom plate, a receiving groove provided on the second bottom plate, and a An upper platen device moving along the height direction, and a second gas hood movable along the height direction; (B) placing a foamed raw material in the cavity formed by the upper and lower molds closing, the first The gas hood moves downward along the height direction to close to the first bottom plate and cover the upper and lower molds, and evacuates the space defined by the first gas hood and the first bottom plate to achieve a predetermined vacuum degree (C) heating the upper and lower molds to cross-link and expand the foamed raw materials contained in the mold cavity into a foam; (D) break the vacuum and move the first gas hood upward from the foam The first bottom plate and the upper and lower molds, then move the upper mold upward away from the lower mold; (E) use the conveying unit to move the foam from the molding unit to the cooling tank of the cooling and setting unit, the Cooling water is installed in the tank, and the foam is cooled and shaped by water cooling; (H) The upper platen device moves down along the height direction, and presses down the foam to completely submerge it in cooling water; (F) The second gas hood moves down along the height direction to the second The bottom plate is densely covered with the container, and then a positive pressure is applied to the space defined by the second gas hood and the second bottom plate to cool and shape the foam under a positive pressure environment; (G) Move away The second gas hood takes out the foam that is cooled and shaped. The pressure-control forming method for precisely controlling the size of the foam as described in claim 1, wherein the inner wall of the cavity formed by closing the upper and lower molds has a plastic pattern. The pressure-control forming method for precisely controlling the size of the foam as described in claim 1, wherein the conveying unit has a sliding device and a fixing device provided on the sliding device and movable in the height direction, step E is After the fixing device is moved above the lower mold by using the sliding device, the fixing device moves downward along the height direction and adsorbs the foam and then moves upward, and then the sliding device moves to the upper side of the container again and is released Absorb the foam to make the foam fall into the tank.

Images