Particle filter as well as method for the manufacture thereof

Patent metadata

Field	Value
Publication number	US-10537841-B2
Application number	US-201615337345-A
Country	US
Kind code	B2
Filing date	Oct 28, 2016
Priority date	Oct 30, 2015
Publication date	Jan 21, 2020
Grant date	Jan 21, 2020

Abstract

A method for manufacturing a filter (1) for gas masks includes providing a flat paper and folding the paper into a pleated preform. The filter element (2) is separated from the pleated preform (6) and is inserted into a housing (3). The inserted filter element (2) is connected to the housing (3) at least at some points. This filter elements (2) may have a polygonal outer contour, upon separating the element from the pleated filter preform (6). A foam and/or an adhesive is applied to an outer edge of the filter element (2), arranged on the circumference of the filter element, for an at least partial sealing of an edge (5). This establishes a connection to the housing (3) in at least some sections.

First claim

What is claimed is:

1. A method for manufacturing a filter for gas masks, the method comprising the steps of:
providing a flat paper material;
folding the flat paper material to form a pleated preform;
separating the pleated preform into at least one filter element;
providing a housing;
inserting the filter element into the housing; and
establishing a connection between the inserted filter element and the housing at least at some points, by applying a foam or an adhesive or both a foam and an adhesive to an outer edge of the filter element, which outer edge is arranged on a circumference of the filter element, for the at least partial circumferential sealing of the edge, which sealing establishes the connection of the filter element to the housing in at least some sections;
wherein the steps of establishing the connection of the filter element to the housing with the circumferential sealing of the edge are carried out in one working step.

2. A method in accordance with claim 1 , wherein:
the step of separating the pleated preform into at least one filter element comprises providing the filter element with at least three corners in a plane, which plane is at right angles to a principle inflow direction of the filter;
the housing is provided with a peripheral wall with a plurality of curved sections or at least three corners; and
the filter element is inserted into the housing with the housing wall enclosing the filter element at filter element outer edges.

3. A method in accordance with claim 1 , wherein
the housing is provided with a peripheral wall;
the filter element is inserted into the housing with the housing wall enclosing the filter element at filter element outer edges with a gap provided between the filter element and the peripheral wall; and
filling the gap with the foam or the adhesive or by casting or any combination of the foam and the adhesive and the casting.

4. A method in accordance with claim 1 , wherein:
the pleated preform is connected to at least one spacer for stabilizing a fold shape; or
the filter element is connected to at least one spacer for stabilizing a fold shape; or
both the pleated preform is connected to at least one spacer for stabilizing a fold shape and the filter element is connected to at least one spacer for stabilizing a fold shape.

5. A method in accordance with claim 4 , further comprising:
applying traces of glue as the spacer for stabilizing the fold shape in at least some sections; or
applying traces of glue as an edge seal in at least some sections, after separating the pleated preform into the filter element; or
applying traces of glue as the spacer for stabilizing the fold shape in at least some sections and applying traces of glue as an edge seal in at least some sections, after separating the pleated preform into the filter element.

6. A method in accordance with claim 1 , wherein a plurality of filter elements, which each have six corners in a plane lying at right angles to the principle inflow direction of the filter, are separated from the pleated preform.

7. A method in accordance with claim 1 , wherein separating the pleated preform into at least one filter element comprises cutting a plurality of filter elements from the pleated preform with a cutting tool.

8. A method in accordance with claim 1 , wherein separating the pleated preform into at least one filter element comprises separating a plurality of filter elements from the pleated preform with a laser.

9. A method in accordance with claim 1 , wherein the filter element is freely foamed in the area of its outer edges in at least some sections without a defined contour.

10. A method in accordance with claim 1 , wherein polyurethane is at least partly used as the foam.

11. A method in accordance with claim 1 , wherein:
said applying of the foam includes foaming the outer edge of the filter element to create a seal to seal the outer edge of the filter element.

12. A method accordance with claim 11 , wherein:
the seal at the outer edge of the filter element is produced after setting of the foam.

13. A method in accordance with claim 1 , wherein:
said inserting of the filter element produces a gap between the outer edge and the housing;
said applying of the foam including having the gap entirely foamed to both seal the outer edge and fix the filter element in the housing.

14. A method for the manufacture of a filter for gas masks, the method comprising the steps of:
providing a flat paper material;
folding the flat paper material to form a pleated preform;
separating the pleated preform into at least one filter element with at least three corners in a plane, which is at right angles to the principle inflow direction of the filter;
providing a housing with a housing wall, which housing wall is curved in at least some sections or has at least three corners;
inserting the filter element into the housing with the housing wall enclosing the filter element at outer edges of the filter element; and
establishing a connection between the inserted filter element and the housing at least at some points, wherein the filter element is foamed such that an outer contour is produced and the filter element is connected to a filter housing in a particle-impermeable manner.

Assignees

• Draeger Safety Ag & Co Kgaa

Inventors

• Hoder Matthias
• Hake Stephan
• Ahrens Mathias
• Görndt Andrea

Classifications

• B01D2275/20

  Shape of filtering material · CPC title

• B01D46/0005

  Mounting of filtering elements within casings, housings or frames (B01D46/2422 takes precedence) · CPC title

• B01D2275/206

  Special forms, e.g. adapted to a certain housing · CPC title

• B01D46/10

  Particle separators, e.g. dust precipitators, using filter plates, sheets or pads having plane surfaces · CPC title

• A62B23/02 Primary

  for respirators · CPC title