초록 ▼

A method of molding a generally hollow front triangle for a bicycle frame of composite materials, such as heat curable structural resins. Layers of the composite material are shaped to form a front triangle shell and this shell is compressed against a mold using at least one inflatable bladder route

A method of molding a generally hollow front triangle for a bicycle frame of composite materials, such as heat curable structural resins. Layers of the composite material are shaped to form a front triangle shell and this shell is compressed against a mold using at least one inflatable bladder routed to the outside through a passageway passing through a modified bottom bracket sleeve or a modified head tube sleeve.

대표청구항 ▼

A method of molding a generally hollow front triangle for a bicycle frame, said front triangle comprising a hollow top tube portion, a hollow down tube portion, a hollow seat tube portion, a hollow head junction connecting said top tube portion and said down tube portion, a hollow seat junction conn

A method of molding a generally hollow front triangle for a bicycle frame, said front triangle comprising a hollow top tube portion, a hollow down tube portion, a hollow seat tube portion, a hollow head junction connecting said top tube portion and said down tube portion, a hollow seat junction connecting said top tube portion and said seat tube portion, and a hollow bottom bracket junction connecting said down tube portion and said seat tube portion, said head junction containing a steering support means having a head tube sleeve, said seat junction containing a seat support means having a seat post sleeve, and said bottom bracket junction containing a pedal support means having a bottom bracket sleeve, said method comprising the steps of: forming a hollow shell having at least one layer of an uncured structural resin and fiber composition and placing said uncured shell adjacent to the inside surfaces of the walls of a mold defining a molding chamber having an interior shape corresponding to the exterior shape of said front triangle, said shell having a generally continuous hollow interior and tube portions and junctions corresponding to said front triangle; placing said head tube and bottom bracket sleeves within a surrounding wall of their respective junctions and transversely to corresponding ends of the connected tube portions; forming a passageway passing transversely through at least one of the bottom bracket sleeve of said pedal support means and the head tube sleeve of said steering support means and through said wall of the corresponding junction(s), said passageway having an opening to the outside in the exterior of the shell; placing in the hollow interior of said shell at least one elongated inflatable bladder for compressing said at least one layer of said structural resin and fiber composition against the inside surfaces of said molding chamber, said at least one bladder being closed at one end and open at the other end and having an extension in fluid communication with said open end; routing said bladder extension to the outside of the shell and the mold through said passageway and said opening, said passageway and said opening being substantially aligned with the portion of said shell containing said open end of said bladder; inflating said at least one bladder with a fluid to compress said at least one layer of said structural resin and fiber composition against the inside surfaces of said molding chamber, said fluid communicating with said at least one bladder through said bladder extension; and, curing said structural resin to form said hollow front triangle.