WELDED SHOE ASSEMBLY
A welded shoe assembly includes a shoe upper with a plastic surface welded to a plastic surface of a bottom unit. The welded shoe assembly is formed, in one implementation, by compressing the shoe upper and a bottom unit against one another between an electrically conductive last and an electrically conductive mold and applying an electrical signal to either the electrically conductive last and/or the electrically conductive mold.
1 . A shoe assembly comprising:
a shoe upper; and
a bottom unit including a plastic surface welded to a plastic surface of the shoe upper.
2 . The shoe assembly of claim 1 , wherein the bottom unit includes a carrier and an array of cushioning elements attached thereto.
3 . The shoe assembly of claim 2 , wherein individual cushioning elements of the array of cushioning elements protrude through apertures in the carrier.
4 . The shoe assembly of claim 2 , wherein each of the cushioning elements includes multiple void cells.
5 . The shoe assembly of claim 2 , wherein each of the cushioning elements includes at least two interfacing void cells.
6 . A method of assembling a shoe comprising:
compressing a shoe upper against a bottom unit between a conductive last and a conductive mold; and
applying an electrical signal to at least one of the conductive last and the conductive mold sufficient to weld the shoe upper to the bottom unit.
7 . The method of claim 6 , wherein the electrical signal is a radio-frequency (RF) signal.
8 . The method of claim 6 , wherein the electrical signal has a frequency substantially between 15 and 70 kilohertz (kHz).
9 . The method of claim 6 , wherein the bottom unit includes a carrier and a number of cushioning elements and the carrier further includes through-holes each sized and shaped to receive a portion of one of the cushioning elements.
10 . The method of claim 9 , further comprising:
positioning each of the cushioning elements within a corresponding one of the through-holes of the carrier.
11 . The method of claim 9 , further comprising:
positioning the carrier within the conductive mold.
12 . The method of claim 9 , further comprising:
positioning the conductive last within the shoe upper; and
positioning the shoe upper directly adjacent to the carrier and within the welding mold.
13 . The method of claim 9 , wherein each of the cushioning elements includes at least one elastically compressible void cell.
14 . The method of claim 9 , wherein each of the cushioning elements includes an array of void cells with at least two interfacing void cells.
15 . The method of claim 6 , wherein the conductive mold includes at least two conductive mold components configured to contact a same surface of the bottom unit.
16 . A welding system comprising:
a electrically conductive mold sized and shaped to receive a bottom unit of a shoe assembly; and
a electrically conductive last sized and shaped for insertion into a shoe upper of the shoe assembly.
17 . The welding system of claim 16 , further comprising:
a transmitter electrically coupled to at least one of the electrically conductive mold and the electrically conductive last.
18 . The welding system of claim 17 , wherein the transmitter is an RF transmitter.
19 . The welding system of claim 16 , wherein the electrically conductive mold includes two mold components.
20 . The welding system of claim 16 , wherein the electrically conductive mold includes a number of indentations for receiving corresponding cushioning elements of the bottom unit.