Extrusion nozzle

US4372739A · kind A · utility

Assignee

• RoGmbH · DE

Inventors

• Heinz Vetter · Weiterstadt, DE
• Ernst Friederich · Darmstadt, DE

Key dates

• Filing date: May 13, 1981
• Grant date: Feb 8, 1983
• Expiry date: May 13, 2001

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B29C2948/92904
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

What is disclosed is an adjustable wide-slit extrusion nozzle containing a distributor channel having a straight exit edge and a cross-section taken from the supply port for the nozzle to one end thereof which corresponds to the equation: EQU R.sub.i =R.sub.o (b/B).sup.1/3, wherein: PA1 B is the width of the distributor channel from the supply port to one end of the channel; PA1 b is a width coordinate measured from one end of the distributor channel; PA1 R.sub.o is the hydraulic radius of the distributor channel at the supply port; and PA1 R.sub.i is the hydraulic radius of the distributor channel at the distance b from the channel end. At least one choker bar insert is placed between the distributor channel and the nozzle mouth; the choker bar has a damming area surface whose length dimensions L.sub.i in the direction of flow at distances b from the channel end correspond to the equation EQU L.sub.i =L.sub.o (b/B ).sup.2/3, wherein PA1 L.sub.o is the length of the damming strip at the supply port; PA1 L.sub.i is the length in flow direction of the damming area at the selected distance b from the channel end; and PA1 b and B are defined as above. The damming area rises above the r…