Abstract: An extrusion apparatus includes first and second die body portions each having a main body and a lip interconnected with the main body wherein the die body portions are joined such that a die outlet is formed between the lips. The apparatus also includes at least one pivoting link coupled to one of the lips and a sliding member coupled to the pivoting link whereby movement of the sliding member causes the pivoting link to pivot and move the one lip relative to the other lip.

Abstract: A feedblock for supplying a multi-layer stream of polymeric material to an extrusion die is provided wherein the dimension of at least some of the layers of the multi-layer stream can be precisely adjusted and/or controlled. The feedblock includes a primary flow path which is used to create a first layer and two secondary flow paths which are used to create a set of second and third layers. The secondary flow paths are positioned relative to the primary flow path such that the second and third layers are deposited on opposing sides of the primary layer in a sandwich-like configuration. Each of the secondary flow paths include a contoured slot through which a secondary fluid stream of polymeric material is deposited onto a primary stream of polymeric fluid flowing in the primary flow path. The contoured slot is geometrically shaped such that adjusting the position of the contoured slot alters the shape of the secondary fluid stream as it is deposited onto the primary flow path.

Abstract: A flow control device is mounted within a channel of an extrusion die, wherein the channel is defined by a base surface and a side surface normal to the base surface. The device includes a main body and an auxiliary body, wherein the main body includes a side portion that sealingly contacts the side surface of the channel when a force is exerted on the side portion, and the auxiliary body is in contact with the base surface of the channel. The device further includes a flexible membrane on a face opposite the auxiliary body which can influence the flow of material through the channel by moving in a direction perpendicular to the direction of material flow. A sealing apparatus is used to prevent leakage of material between the die and the flexible membrane. The sealing apparatus includes a gasket disposed adjacent an end surface of the membrane and means for causing the gasket to apply a force against the end surface such that the gasket seals against the membrane.

Abstract: A membrane assembly for an extrusion die includes a membrane having a deformable main portion and first and second mounting arms integral with the main portion and disposed on opposite sides thereof. The main portion includes a first face and the mounting arms extend away from the first face. The main portion, the mounting arms and a second face opposite the first face form a recess on a side of the main portion opposite the first face and a backing member is disposed in the recess between the mounting arms.

Abstract: A flexible membrane is attached to a holder for controlling flow in an extrusion die. The membrane includes a horizontal portion, first and second curved portions adjacent the horizontal portion, first and second offset portions adjacent the first and second curved portions, and first and second edges adjacent the first and second offset portions. The membrane is formed of a single piece of material. The flow control device including the flexible membrane may be produced by fabricating a membrane holder from a material, fabricating a flexible membrane from the same material, joining the flexible membrane to the membrane holder, and hardening the membrane holder and membrane.

Abstract: A flow control device is mounted within a channel of an extrusion die, wherein the channel is defined by a base surface and a side surface normal to the base surface. The device includes a main body and an auxiliary body, wherein the main body includes a side portion that sealingly contacts the side surface of the channel when a force is exerted on the side portion, and the auxiliary body is in contact with the base surface of the channel. The device further includes a flexible membrane on a face opposite the auxiliary body which can influence the flow of material through the channel by moving in a direction perpendicular to the direction of material flow. A sealing apparatus is used to prevent leakage of material between the die and the flexible membrane. The sealing apparatus includes a gasket disposed adjacent an end surface of the membrane and means for causing the gasket to apply a force against the end surface such that the gasket seals against the membrane.

Abstract: An extrusion apparatus includes first and second die body portions each having a main body and a lip interconnected with the main body wherein the die body portions are joined such that a single die outlet is formed between and bounded by the lips. The apparatus also includes suitable structure for moving the lips to adjust the die outlet.

Abstract: A feedblock for coextrusion apparatus permits profile adjustment of individual layers through the use of flow tuning valves that extend across the width of a main flow through the feedblock.

Abstract: An extrusion die for foam sheet including a die body defining a manifold for conducting a split stream of heated and pressurized foamable thermoplastic melt through separate distribution channels to a die terminus. A pair of mating die lips are arranged on opposed sides of the melt and are constructed to adjustably slide toward and away from each other to vary the flow of a melt. The lips are each mounted to slide along an axis which is tilted rearwardly at an acute angle relative to an orthogonal to the sheet being formed. The mandrel is configured and adapted for quick withdrawal and replacement from an end of the die through a passageway extending through the die transverse to the direction of extrusion of a sheet.

Abstract: An extrusion apparatus includes first and second die body portions each having a main body and a lip interconnected with the main body wherein the die body portions are joined such that a single die outlet is formed between and bounded by the lips. The apparatus also includes suitable structure for moving the lips to adjust the die outlet.

Abstract: A dual-chamber vacuum box for pinning a thermoplastic web to a cooling roll includes a primary vacuum chamber connected to a first vacuum source. The primary vacuum chamber has a first side located proximate a surface of the web at a line of contact between the web and the cooling roll and a second side opposite the first side. A secondary vacuum is chamber connected to a second vacuum source and is positioned adjacent the second side of the primary vacuum chamber. Apparatus is disposed between the primary and secondary vacuum chambers for creating a pressure variation along the line of contact between the web and the cooling roll.

Abstract: An extrusion die includes a die body defining a manifold therein terminating at an outlet and first and second relatively moveable plugs disposed in the manifold each having a plug edge where the plug edges together define a profile. The first and second plugs are moveable to first and second plug positions, respectively, in the manifold and indicators are disposed outside of the die body for indicating the first and second plug positions and the profile.

Abstract: An extrusion apparatus for extruding thermoplastic material includes first and second die body portions that define a manifold which has a back line and is in fluid communication with an outlet through which the thermoplastic material is extruded and wherein the back line is substantially parallel to the outlet. First and second body bolts join the first and second die body portions together. The first and second body bolts are disposed at first and second equal distances, respectively, from the back line and are further disposed on opposite sides of a centerline of the extrusion apparatus at third and fourth unequal distances therefrom, respectively, and are substantially equally spaced from the outlet.

Abstract: A feed block for coextrusion apparatus includes a main body and a flow distribution module removably located therein. The feed block can be readily disassembled for cleaning and maintenance and the flow distribution module may be readily interchanged with another module without the need to disassemble the feed block or other components attached thereto.

Abstract: A slot die head for emitting a coating fluid onto a moving web has a slot orifice, the exit end of which is defined by replaceable inserts, the downstream one of which, relative to the direction of web movement, has a wiping flange cantilevered from a hinge portion thereof. The flange is disposed in use in facing relationship with the web and extends downstream from the slot orifice, so as to be resiliently hingedly movable in directions substantially normal to the web surface for maintaining constant shear levels across the coated area.