Method for manufacturing a midsole formed from two preforms

Patent metadata

Field	Value
Publication number	US-10245798-B2
Application number	US-201615353903-A
Country	US
Kind code	B2
Filing date	Nov 17, 2016
Priority date	Nov 17, 2016
Publication date	Apr 2, 2019
Grant date	Apr 2, 2019

Abstract

A method of manufacturing a midsole for an article of footwear includes placing first and second preforms in a first mold, closing and heating the first mold to produce a midsole preform with a peripheral preform flange, removing the midsole preform from the first mold and allowing it to further expand and cool, placing the midsole preform in a second mold, with a volume of a midsole recess of the second mold being less than a volume of the midsole preform, and a volume of a peripheral recess of the second mold being less than a volume of the peripheral preform flange, closing the second mold thereby compressing the midsole preform and the peripheral preform flange, and heating the second mold to form a midsole with a peripheral flange, allowing the second mold to cool, opening the second mold, and cutting away a peripheral flange of the midsole.

First claim

What is claimed is:

1. A method of manufacturing a midsole for an article of footwear comprising
placing first and second preforms in contact with one another in a preform recess in a first mold, first and second portions of the first mold cooperating to define the preform recess and a peripheral overflow chamber extending about a periphery of the preform recess;
closing the first mold by positioning the first and second portions in contact with one another;
heating the first mold for a predetermined period of time at a predetermined temperature such that the first and second preforms expand within the preform recess and into the peripheral overflow chamber to produce a midsole preform with a peripheral preform flange extending about a periphery of the midsole preform;
removing the midsole preform from the first mold;
allowing the midsole to further expand and cool;
placing the midsole preform in a midsole recess of a second mold and the peripheral preform flange in a peripheral recess of the second mold, first and second portions of the second mold cooperating to define the midsole recess and the peripheral recess extending about a periphery of the midsole recess, with a volume of the midsole recess being less than a volume of the midsole preform, and a volume of the peripheral recess being less than a volume of the peripheral preform flange;
closing the second mold by positioning the first and second portions in contact with one another, thereby compressing the midsole preform and the peripheral preform flange to produce a midsole with a peripheral flange;
heating the second mold for a predetermined period of time at a predetermined temperature;
allowing the second mold to cool;

opening the second mold; and
trimming away the peripheral flange of the midsole.

2. The method of claim 1 , wherein the midsole preform recess comprises a first recess formed in the first portion of the first mold and a second recess formed in the second portion of the first mold, and the overflow recess comprises a first overflow recess formed in the first portion of the first mold and a second overflow recess formed in the second portion of the first mold.

3. The method of claim 1 , wherein the midsole recess comprises a first recess formed in the first portion of the second mold and a second recess formed in the second portion of the second mold, and the peripheral recess comprises a first peripheral recess formed in the first portion of the second mold and a second peripheral recess formed in the second portion of the second mold.

4. The method of claim 1 , wherein the first preform includes a first preform peripheral flange and the second preform includes a second preform peripheral flange.

5. The method of claim 1 , wherein the first mold is heated for between approximately 15 minutes and approximately 20 minutes, and the first temperature is approximately 130° C.

6. The method of claim 1 , wherein the second mold is heated for approximately 15 minutes and is cooled to below approximately 35° C.

7. The method of claim 1 , wherein the first and second preforms are formed of ethylene vinyl acetate.

8. The method of claim 1 , wherein the first preform has a first color and the second preform has a second color different from the first color, and wherein a boundary between the first color and the second color bisects the peripheral flange of the midsole.

9. The method of claim 1 , wherein a physical property of the first preform is different than a physical property of the second preform.

10. A method of manufacturing a midsole for an article of footwear comprising
placing a first preform having a first preform peripheral flange and a second preform having a second preform peripheral flange in contact with one another in a preform recess in a first mold, the first and second preforms being positioned in a preform recess in the first mold, a first recess formed in a first portion of the first mold and a second recess formed in a second portion of the first mold cooperating to define the preform recess, the first and second preform peripheral flanges being positioned in a peripheral overflow chamber of the first mold, a first overflow recess formed in the first portion of the first mold and a second overflow recess formed in the second portion of the first mold cooperating to define the peripheral overflow chamber;
closing the first mold by positioning the first and second portions in contact with one another;
heating the first mold for a predetermined period of time at a predetermined temperature such that the first and second preforms expand within the preform recess and the first and second preform peripheral flanges expand within the peripheral overflow chamber to produce a midsole preform with a peripheral preform flange extending about a periphery of the midsole preform;
removing the midsole preform from the first mold;
allowing the midsole to further expand and cool;
placing the midsole preform in a midsole recess of a second mold and the peripheral flange in a peripheral recess of the second mold, a first recess in the first portion of the second mold and a second recess in the second portion of the second mold cooperating to define the midsole recess, a first peripheral recess in the first portion of the second mold and a second peripheral recess in the second portion of the second mold cooperating to define the peripheral recess, and the peripheral recess extending about a periphery of the midsole recess, with a volume of the midsole recess being less than a volume of the midsole preform and a volume of the peripheral recess being less than a volume of the peripheral flange;
closing the second mold by and compressing the midsole preform and the peripheral preform flange by aligning the first recess in the first portion of the second mold and the second recess in the second portion of the second mold and bringing the first and second portions into contact with one another to form a midsole with a peripheral flange;
heating the second mold for a predetermined period of time at a predetermined temperature;
allowing the second mold to cool;
opening the second mold; and
cutting away the peripheral flange of the midsole.

11. The method of claim 10 , wherein the predetermined period of time is between approximately 15 minutes and approximately 20 minutes, and the first temperature is approximately 130° C.

12. The method of claim 10 , wherein the first and second preforms are formed of ethylene vinyl acetate.

13. The method of claim 10 , wherein the first preform has a first color that is different than a second color of the second preform.

14. The method of claim 13 , wherein a boundary between the first color and the second color bisects the peripheral flange of the midsole.

15. The method of claim 10 , wherein a physical property of the first preform is different than a physical property of the second preform.

Assignees

• Nike Inc

Inventors

• Wan Tee L

Classifications

• B29D35/142 Primary

  Soles · CPC title

• B29C44/08

  using several expanding {or moulding} steps · CPC title

• B29C44/04

  consisting of at least two parts of chemically or physically different materials, e.g. having different densities · CPC title

• B29K2023/083

  EVA, i.e. ethylene vinyl acetate copolymer · CPC title

• B29C44/5627

  by mechanical deformation, e.g. crushing, embossing, stretching · CPC title