Apparatus for making spunbond from continuous filaments

Patent metadata

Field	Value
Publication number	US-2018282925-A1
Application number	US-201815939703-A
Country	US
Kind code	A1
Filing date	Mar 29, 2018
Priority date	Mar 31, 2017
Publication date	Oct 4, 2018
Grant date	—

Abstract

An apparatus for making a nonwoven spunbond web has a spinneret for making endless filaments moving in a predetermined direction. A monomer extractor downstream from the spinneret has an upstream extractor end face directed upstream and forming a gap with a downstream spinneret end face. A cooler downstream of the extractor for the filaments has an upstream cooler end face forming with a downstream extractor end face a second gap. A stretcher downstream of the cooler for the cooled filaments has an upstream stretcher end face forming a third gap with the downstream cooler end face. The filaments are deposited on a web former by the stretcher to form the nonwoven spunbond web. A deformable seal for seals one of the gaps, and means connected to the deformable seal press the seal against the end faces forming the one gap with a variable pressure or contact face.

First claim

We claim:

1 . An apparatus for making a nonwoven spunbond web from endless thermoplastic filaments, the apparatus comprising:
a spinneret for spinning the endless filaments moving in a predetermined filament direction and having a downstream spinneret end face directed downstream; a monomer extractor downstream in the filament direction from the spinneret and having an upstream extractor end face directed upstream and forming a gap with the downstream spinneret end face, the monomer extractor having an opposite downstream extractor end face directed downstream; a cooler downstream of the extractor for cooling the filaments and having an upstream cooler end face forming with the downstream extractor end face a second gap and an opposite downstream cooler end face; a stretcher downstream of the cooler for stretching the cooled filaments and having an upstream stretcher end face forming a third gap with the downstream cooler end face, the extractor, cooler, and stretcher forming a continuous passage extending in the filament direction; and a web former on which the filaments are deposited by the stretcher to form the nonwoven spunbond web; and a deformable seal for sealing one of the gaps; and means connected to the deformable seal for pressing the seal against the end faces forming the one gap with a variable pressure or contact face.

2 . The apparatus defined in claim 1 , wherein the dimension parallel to the filament direction of the first gap between the spinneret and the monomer extractor and/or the width of the second gap between the monomer extractor and the cooler and/or the width of the third gap between the cooler and the stretcher in the operating state of the apparatus is 3 to 35 mm and the seal seals across this dimension.

3 . The apparatus defined in claim 2 , wherein non-uniformities of the dimension the one gap are compensated for by variation of the dimension of the seal in the filament direction.

4 . The apparatus defined in claim 2 , wherein the seal is adjustable or deformable in the filament direction gap by 3 to 20 mm.

5 . The apparatus defined in claim 1 , wherein the seal extends annularly a filament flow passage extending downward ain the filament direction through the extractor, cooler, and stretcher.

6 . The apparatus defined in claim 1 , wherein a plurality of the seals are arranged adjacent to one another in the one gap.

7 . The apparatus defined in claim 1 , wherein the means for pressing can press the seal against the end faces of the respective gap with a pressure of more than 2000 Pa.

8 . The apparatus defined in claim 1 , wherein the seal is hollow and fillable with a fluid medium by the pressing means and adjustment of the seal is accomplished by introducing the fluid medium into the seal or by removing the fluid medium from the seal.

9 . The apparatus defined in claim 1 , wherein the seal is inflatable.

10 . The apparatus defined in claim 1 , further comprising:
means usable during maintenance of the apparatus for shortening the seal in the filament direction and thereby permitting relative movement in a direction transverse to the filament direction of the end faces defining the one gap.

11 . The apparatus defined in claim 10 , wherein the shortening of the seal is effected by moving the seal out of contact with one of the end faces forming the one gap.

12 . The apparatus defined in claim 1 , wherein the means for pressing includes a spring effective in the filament direction on the seal.

13 . The apparatus defined in claim 12 , wherein stiffness of the spring is such that the seal is pressed in the filament direction against one of the end faces forming the one gap.

14 . The apparatus defined in claim 13 , wherein the spring is adjustable so as to pull the seal away from the one end face.

15 . The apparatus defined in claim 1 , wherein the cooler and the stretcher form a subassembly closed to entry of air from outside the passage.

16 . The apparatus defined in claim 1 , further comprising:
a diffuser between the stretcher and the web former, forming part of the passage, receiving the filaments from the stretcher, and having secondary air inlet gaps through which secondary air passes into the diffusor.

17 . The apparatus defined in claim 16 , wherein the web former includes a foraminous belt on which the filaments are deposited by the diffuser, the apparatus further comprising:
extractor means juxtaposed with the web former for drawing tertiary air in the filament direction through the belt and along outer surfaces of the diffusor so as to mix with primary air flowing in the filament direction through the passage.

18 . The apparatus defined in claim 16 , wherein the secondary air inlet gaps open into the diffuser at an angle of less than 100° to the filament flow direction.

19 . The apparatus defined in claim 16 , wherein a ratio of volume flows of the primary and secondary air are less than 5:1.

20 . The apparatus defined in claim 16 , wherein walls of the diffuser converge downstream of the secondary air inlet gaps.

21 . The apparatus defined in claim 20 , wherein after converging at a constriction downstream in the filament direction from the secondary air inlet gaps, the walls of the diffuser diverge.

22 . The apparatus defined in claim 17 , wherein the belt and a region of the belt underneath the diffuser has a width at least 20% greater than a width of the diffuser at a downstream end of the diffuser walls.

Assignees

• Reifenhaeuser Masch

Inventors

• Frey Detlef
• Neuenhofer Martin
• Sommer Sebastian

Classifications

• D01D5/092 Primary

  in shafts or chimneys · CPC title

• D01D5/0985

  by means of a flowing gas (e.g. melt-blowing) · CPC title

• D01D13/02

  Elements of machines in combination · CPC title

• D04H3/02

  characterised by the method of forming fleeces or layers, e.g. reorientation of yarns or filaments · CPC title

• D01D7/00

  Collecting the newly-spun products ({D01D5/0076 takes precedence;} collecting newly-spun products with the imparting of twist D01H) · CPC title