Method for sealing the edge of a filter medium to a filter assembly and the filter assembly produced thereby
AssigneeRacal Filter Technologies, Ltd.
InventorKeith S. Marble
Life of this patent
Estimating the term…
Abstract
Improved filter assemblies are provided having a pleated filter medium attached to a support frame utilizing an improved manufacturing method employing a welding process to seal the pleated edges of the filter medium to an inwardly protruding sealing means provided on the frame around the inside perimeter thereof, forming a final filter assembly exhibiting an essentially leak-proof edge seal.
Claims36
A filter assembly comprising, in combination:
- an enclosed frame defining a center opening, and having an inside surface, an upstream fluid inlet and a downstream fluid outlet and an inwardly projecting sealing means running continuously in a horizontal plane along the inside surface of said frame;
- a pleated filter medium positioned in said frame across said center opening between said inlet and said outlet, having its lateral perimeter edge welded to said frame along said sealing means, wherein said sealing means has a preformed shape corresponding to the shape of the lateral perimeter edge of said filter medium to ensure the formation of a leak-proof edge seal and to resist pleat deformation.
A filter assembly, adapted for insertion within a housing and adapted to be sealed along the perimeter of said housing said housing having at least four sides and at least two opposing ends defining a flow-through opening, the filter assembly being sized to fit within said housing, and comprising, in combination, two or more frame members having an inwardly projecting sealing means running continuously in a horizontal plane along the inside surface of each of said frame members;
- a pleated filter medium adapted to conform in shape to the shape of said housing, having at least two opposed pleated side edges, each of which is welded to respective ones of said frame members along said sealing means, wherein said sealing means has a preformed shape corresponding to the shape of the opposed pleated side edges of said filter medium to ensure the formation of an edge seal which is essentially leak-proof and which will resist pleat deformation occurring due to forces exerted by a fluid stream passing through said filter once said assembly is inserted within said housing.
A method for sealing the pleated perimeter edge of a filter medium to a frame member having an inwardly projecting sealing means running continuously in a horizontal plane along the inside surface of said frame member wherein said sealing means has a preformed shape corresponding to the contours of the lateral perimeter edge of the filter medium using welding techniques to form a filter assembly, comprising:
- a. positioning the filter medium over a base fixture having its upper surface contoured to correspond to the pleat height and pleat spacing present in the filter medium and aligning the pleats present in the filter medium to rest on and be contiguous with the corresponding contours in the base fixture;
- b. placing the frame member on top of the filter medium edge so that the sealing means bottom surface contacts and is contiguous with the top of the filter medium edge;
- c. positioning a welding horn, adapted to have a size and shape corresponding to the pleat shape of at least one filter medium pleat, to be in contact with the top surface of the sealing means, thereby sandwiching the sealing means and filter medium edge between the welding horn and the base fixture;
- and
- d. contacting the top surface of the sealing means with an activated welding horn to effect a continuous weld at the interface between the filter medium edge and the sealing means.
A method for sealing the pleated perimeter edge of a filter medium to a frame member having an inwardly projecting sealing means running continuously in a horizontal plane along the inside surface of said frame medium wherein said sealing means has a preformed shape corresponding to the contours of the lateral perimeter edge of the filter member using welding techniques to form a filter assembly, comprising:
- a. positioning the frame member over a base fixture having its upper surface contoured to correspond to the pleat height and pleat spacing present in the filter medium and aligning the pleats present in the sealing means to rest on and be contiguous with the corresponding contours in the base fixture;
- b. placing the filter medium edge on top of the sealing means surface so that the sealing means top surface contacts and is contiguous with the bottom of the filter medium edge;
- c. positioning a welding horn, adapted to have a size and shape corresponding to the pleat shape of at least one filter medium pleat, to be in contact with the top surface of the filter medium edge, thereby sandwiching the filter medium edge and sealing means between the welding horn and the base fixture;
- and
- d. contacting the top surface of the filter medium edge with an activated welding horn to effect a continuous weld at the interface between the filter medium edge and the sealing means.
A filter assembly, comprising:
- a frame member having an inner and outer wall;
- a filter medium having a perimeter and a pleated side edge along a portion of said perimeter;
- a ledge located on the inner wall of the frame member, the ledge having a shape which conforms to the shape of the pleated side edge of the filter medium;
- wherein
- the pleated side edge of the filter medium is welded to the frame member along the ledge.
A filter assembly, comprising:
- a filter frame having first and second opposite side walls, the first and second opposite side walls having inner and outer surfaces;
- a pleated filter medium having first and second pleated side edges;
- a ledge located on each of the inner surfaces of the first and second opposite side walls, the ledge located on the first side wall has a shape which substantially conforms to the shape of the first pleated side edge and the ledge located on the second side wall has a shape which substantially conforms to the shape of the second pleated side edge;
- wherein
- the first pleated side edge of the filter medium is welded along the ledge located on the first side wall and the second pleated side edge is welded along the ledge located on the second side wall.
Dependencies are inferred from the claim text.