초록 ▼

A flow control valve including a movable part and a housing for accommodating the movable part may be produced by molding the components in sequential steps. Preferably, the housing is molded in a first step and the movable part is molded in an at least partially closed position in a second step in

A flow control valve including a movable part and a housing for accommodating the movable part may be produced by molding the components in sequential steps. Preferably, the housing is molded in a first step and the movable part is molded in an at least partially closed position in a second step in the same mold. This method enables the surface of the housing to serve as at least a portion of the mold for forming a substantially sealing portion of the movable part such that a very close tolerance between these components is achieved. The movable part is preferably a butterfly disc and the housing is preferably a butterfly valve housing.

대표청구항 ▼

A mold for producing a flow control valve including a valve housing, a channel extending through said valve housing and defining a boundary surface, and a valve body rotatably arranged in said channel about an axis of rotation and having a peripheral surface, said peripheral surface and said boundar

A mold for producing a flow control valve including a valve housing, a channel extending through said valve housing and defining a boundary surface, and a valve body rotatably arranged in said channel about an axis of rotation and having a peripheral surface, said peripheral surface and said boundary surface together forming an interengaging pair of surfaces in a predetermined at least partially closed position of said valve body, said mold comprising at least two outer mold parts movable in a first plane between an extended position and a retracted position, confronting surfaces of said mold parts in said extended position contacting one another to define a through passage extending in a second plane perpendicular to said first plane, at least a portion of said through passage having a predetermined diameter in said extended position of said mold parts, said confronting surfaces of said mold parts in said retracted position being spaced apart from one another, opposing core members arranged in said mold parts and slidable in said through passage between an extended position and a retracted position, confronting surfaces of said core members in said extended position contacting one another to define said boundary surface of said -valve housing, said confronting surfaces of said core members in said retracted position defining a portion of a molding cavity for said valve body, and at least one pin member assembled in one of said mold parts and movable in a sliding direction between an extended position and a retracted position, an inner end of said at least one pin member in said extended position extending into said through passage for engagement with one of said core members, said inner end of said at least one pin member in said retracted position being spaced apart from said one core member, said mold having a first configuration for molding said valve housing in which said mold parts, said core members and said at least one pin member are in said extended positions and a second configuration for molding said valve body in which said mold parts are in said extended position and said core members and said at least one pin member are in said retracted positions.