초록 ▼

Apparatus according to a disclosed embodiment are provided for molding a unit of a second material onto an article made of a first material. An inflatable, flexible bladder is fluidly connectable to a source of a pressurized fluid, such as compressed air. The pressurized fluid is used to inflate the

Apparatus according to a disclosed embodiment are provided for molding a unit of a second material onto an article made of a first material. An inflatable, flexible bladder is fluidly connectable to a source of a pressurized fluid, such as compressed air. The pressurized fluid is used to inflate the bladder such that, when the bladder is at least partially inflated with the fluid, the article may be pushed against the bladder to invert the bladder and cause the exterior surface of the bladder to form a mold around at least a portion of the article.

대표청구항 ▼

Apparatus according to a disclosed embodiment are provided for molding a unit of a second material onto an article made of a first material. An inflatable, flexible bladder is fluidly connectable to a source of a pressurized fluid, such as compressed air. The pressurized fluid is used to inflate the

Apparatus according to a disclosed embodiment are provided for molding a unit of a second material onto an article made of a first material. An inflatable, flexible bladder is fluidly connectable to a source of a pressurized fluid, such as compressed air. The pressurized fluid is used to inflate the bladder such that, when the bladder is at least partially inflated with the fluid, the article may be pushed against the bladder to invert the bladder and cause the exterior surface of the bladder to form a mold around at least a portion of the article. ifice between a mandrel and an outer ring, said improvement comprising: moving the biodegradable material, in a direction having a component transverse to the flow direction, during extrusion, wherein said moving comprises rotating an outer ring relative to a mandrel. 8. A process for manufacturing biodegradable shaped products of increased strength, said process comprising: extruding a biodegradable material, wherein said extruding comprises moving the biodegradable material in a first direction through an annular orifice to produce a cylindrical extrudate, wherein the orifice is defined by a mandrel and an outer ring and wherein said shearing comprises rotating the outer ring relative to the mandrel; shearing the biodegradable material, in a second direction having a component transverse to the first direction, during said extruding; compressing the extrudate; and molding the compressed extrudate of biodegradable material into a structure. 9. A process as in claim 8, further comprising stretching the extrudate along the first direction before said compressing and said molding the extrudate. 10. An extrusion die for extruding biodegradable material, said extrusion die comprising: a cylindrical mandrel; a cylindrical outer ring positioned around said mandrel; an annular extrusion orifice between said mandrel and said outer ring; a member in communication with at least one defining member of said annular extrusion orifice which produces angular relative movement between said outer ring and said mandrel; and a flow control device which controls flow of biodegradable material through the extrusion die, wherein the flow control device comprises a mechanism which translates said outer ring to adjust the width of said annular extrusion orifice. 11. An extrusion die as claimed in claim 10, further comprising a mounting plate having a flow bore which conducts biodegradable material toward said annular extrusion orifice, wherein said outer member is rotatably mounted to said mounting plate, and wherein said mandrel is fixedly mounted to said mounting plate. 12. An extrusion die as in claim 10, wherein said flow control device comprises a gap adjustment ring which adjusts the width of said annular extrusion orifice, wherein said gap adjustment ring adjusts the width of said annular extrusion orifice by translating the outer member. 13. An extrusion die as in claim 10, wherein said flow control device comprises a flow control channel which throttles flow of the biodegradable material through the die, and said extrusion die further comprises a mounting plate and at least one spacer, wherein said mandrel is attached to said mounting plate with said at least one spacer between, wherein said mounting plate and said mandrel define said flow control channel. 14. An extrusion die for extruding biodegradable material, said extrusion die comprising: a cylindrical mandrel; an outer member positioned around said mandrel; an extrusion orifice between said mandrel and said outer member; a mounting plate having a flow bore which conducts biodegradable material toward said extrusion orifice, wherein said mandrel is fixedly mounted to said mounting plate and said outer member is movably mounted to said mounting plate; and a member which moves said outer member relative to said mandrel in a direction having a component transverse to an extrusion direction of biodegradable material through the extrusion orifice; a flow control device which controls flow of biodegradable material through the extrusion die, wherein said flow control device comprises a flow control channel upstream of the extrusion orifice, wherein the flow control channel throttles flow of the biodegradable material through the die. 15. An extrusion die as claimed in claim 14, wherein said mandrel is attached to said mounting plate with said at least one spacer between, wherein said mounting plate and said mandrel define said flow control channel. 16. An extr