Mold for footwear with sipes and method of manufacturing same
A mold used to form a midsole for an article of footwear and a method of manufacturing are disclosed. The mold includes a first portion and a second portion cooperating to define a midsole recess, the first portion including a major recess and plurality of wall segments extending throughout the major recess and cooperating to define a plurality of minor recesses. A fillet is provided at each intersection of adjacent wall segments. The mold may have a draft angle of less than or equal to approximately 2.5 degrees.
1. A method of manufacturing an article of footwear comprising
injecting a material into a midsole recess in a mold, the mold including a first portion and a second portion cooperating to define the midsole recess, the first portion including a major recess and a plurality of wall segments extending throughout the major recess and cooperating to define a plurality of minor recesses, at least one wall segment having a thickness less than or equal to about 2.5 mm, a height of between approximately 5 mm and approximately 10 mm, and a draft angle of less than or equal to approximately 2.5 degrees, a fillet provided at each intersection of adjacent wall segments, at least one fillet having a radius of between approximately 1 mm and approximately 5 mm;
closing the mold by positioning the first and second portions in contact with one another;
heating the mold for a predetermined period of time at a predetermined temperature to form a midsole;
removing the midsole from the mold; and
allowing the midsole to expand.
2. The method of claim 1 , wherein the material is EVA.
3. The method of claim 1 , wherein the first portion includes a plurality of central recesses and a plurality of ribs, each central recess formed in a bottom surface of a minor recess, and each rib extending upwardly from the bottom surface around a periphery of one of the central recesses.
4. The method of claim 1 , further comprising the step of securing the midsole to an upper.
5. The method of claim 1 , further comprising the step of securing an outsole to the midsole.
6. The method of claim 1 , wherein a first plurality of the wall segments extend substantially transversely across the major recess and a second plurality of the wall segments extend substantially longitudinally along the major recess.
7. The method of claim 1 , wherein the midsole recess is substantially foot-shaped.
8. A mold for forming a midsole for an article of footwear comprising:
a first portion including:
a major recess formed therein;
a plurality of wall segments extending throughout the major recess and defining a plurality of minor recesses within the major recess, at least one wall segment having a thickness less than or equal to about 2.5 mm, a height of between approximately 5 mm and approximately 10 mm, and a draft angle of less than or equal to approximately 2.5 degrees; and
a plurality of fillets, each fillet positioned between a pair of adjacent wall segments, at least one fillet having a radius of between approximately 1 mm and approximately 5 mm; and
a second portion, the second portion and the major recess cooperating to define a midsole recess when the first portion and the second portion are positioned in contact with one another such that the mold is in a closed condition.
9. The mold of claim 8 , wherein a first plurality of the wall segments extend substantially transversely across the major recess and a second plurality of the wall segments extend substantially longitudinally along the major recess.
10. The mold of claim 8 , wherein the midsole recess is substantially foot-shaped.