Liquid purification or separation – Filter – Medium – cleaner or agitator moved by fluid
Reexamination Certificate
1999-08-25
2001-04-03
Drodge, Joseph W. (Department: 1723)
Liquid purification or separation
Filter
Medium, cleaner or agitator moved by fluid
C055S490000, C055S521000, C210S488000, C210S497010
Reexamination Certificate
active
06209728
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a filter element to be used in a filtering apparatus for filtering a fluid.
DESCRIPTION OF THE RELATED ART
Conventionally, as a filter element to be attached to the filtering apparatus for filtering a fluid, various kinds of filter elements having various structures are known.
Filter elements as described above are, however, generally disposable type, and even though they are reusable by cleaning, much time and effort is required to recover them because it is hard to remove foreign materials deposited thereon, or sometimes they have to be soaked into a specific chemical agent for a long time to remove the same.
Therefore, it would be desirable if foreign materials deposited on a filter element can be easily removed and thus the filter element is easily recovered for reuse.
DISCLOSURE OF THE INVENTION
An object of the present invention is to provide filter elements with enhanced ease-of-handle features and excellent usability which can filter out foreign materials to be removed from a fluid satisfactorily and from which deposited foreign materials blocking the filtration gaps can be easily washed out in a short period of time.
In order to achieve above described challenge, according to the present invention, a filter element comprising a cylindrical filter medium and a holder for holding the filter medium is provided. The filter medium is constructed to be resiliently expandable in the direction of axis and to be subject to deformation of the filtration gaps in varying sizes in accordance with the expansion thereof. The filter medium includes a compression limiting means for providing required filtering gaps by limiting the amount of compression applied to the filter medium, and is held by the holder in such a manner that the amount of compression can be adjusted.
According to the present invention, the filter medium is made of a hard resilient material having no compressibility in itself.
According to a detailed embodiment of the present invention, the filter medium is formed by winding a resilient wire rod in a helical fashion including filtration gaps between adjacent wound portions and a plurality of notches for providing the filtration gaps between adjacent wound portions. The notches may be formed by bending parts of the resilient wire rod.
According to another detailed embodiment of the present invention, the filter medium is formed by stacking a plurality of annular resilient plates, and each plate has a plurality of spring portions for resiliently widening the space between adjacent plates and a plurality of projections for providing filtering gaps between adjacent plates when the filter medium is under compression. The spring portions and projections may be formed by making incisions on the plate and raising them up.
According to still another detailed embodiment of the present invention, the filter medium is formed by stacking a plurality of annular spring members and a plurality of annular gap forming members alternately in layers. The spring members are corrugated in the direction of their thickness to be resiliently deformed into the shape of flat plates when the filter medium is under compression. The gap forming members is provided with a plurality of radially extending filtration channels thereon. The filtration channels may be formed on both front and back surfaces of the gap forming members.
The filter element according to the present invention, having structure described so far, is provided with required filtration gaps in the state that the filter medium is compressed to ensure that a fluid is filtered through these filtration gaps. In order to release the compressed state of the filter medium for cleaning, the filtration gaps can be expanded sufficiently by manual operation, by means such as an actuator, or by resilience of a resilient wire rod and/or resilient plates which constitute the filter medium, so that foreign materials deposited on the filter element may be removed easily and satisfactory.
In other words, in the case where the filter medium is configured in the form of coil by a resilient wire rod, when it is under compression, the filtration gaps are provided by notches formed on the resilient wire rod, and when it is removed from the filtering apparatus, the resilient wire rod is expanded because the filter medium is released from compressed state and thus the filtration gaps widen more or less uniformly.
In the case where the filter medium is configured by annular resilient plates, when it is under compression, the filtration gaps in constant widths are provided by means of projections formed on the respective plates, and when it is released from the compressed state, the filtration gaps provided between adjacent plates is widened by spring portions formed on the respective plates.
In addition, in the case where the filter medium is configured by stacking spring members and gap forming members alternately, when the filter medium is under compression, the spring members are flattened into the shape of plates respectively and then filtration gaps of uniform width are provided by the filtration channels formed on the gap forming members. When compression is released, the filtration gaps are widened by restoration of spring members corrugated in the direction of the thickness.
Since the filtration gaps of the filter element can be easily widened as described above, foreign materials filtered out may easily be removed by cleaning. Especially when the filter medium is formed of separate resilient plates or spring members, or of the gap forming members etc., easier cleaning is ensured because they may be disassembled into pieces for cleaning. In addition, the above mentioned disassembled members may be reassembled with relative ease and thus foreign materials may be removed more easily. With such a structure, the filter element itself is readily recoverable and reusable.
REFERENCES:
patent: 3937281 (1976-02-01), Harnsberger
patent: 4292178 (1981-09-01), Mori et al.
patent: 4430232 (1984-02-01), Doucet
patent: 4690761 (1987-09-01), Orlans
patent: 4707259 (1987-11-01), Doucet
patent: 4804481 (1989-02-01), Lennartz
patent: 5792353 (1998-08-01), Jungi et al.
patent: 438 220 (1967-11-01), None
patent: 0 057 670 (1982-08-01), None
patent: 0 159 961 (1985-10-01), None
patent: 2 201 902 (1988-09-01), None
patent: WO 91/02578 (1991-03-01), None
patent: WO 93/07944 (1993-04-01), None
Endoh Go
Maeda Yoshihisa
Drodge Joseph W.
Oblon & Spivak, McClelland, Maier & Neustadt P.C.
SMC Corporation
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