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US4122015A Expired / Lapsed US ⏱️ 0.0 years remaining

Fortified metal filter and its preparative procedure

Assignee: Nippon Seisen Co Ltd
•
Filing: 1977-06-06
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Granted: 1978-10-24
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Expires: 1997-06-06
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Abstract

Abstract A fortified metal filter possessing a high filtering efficiency, a large pore ratio and a wide net area of fused parts of fine stainless steel wires is prepared by crushing the edges of these wires. The wires utilized in the system are composed of numerous polygonally cross-sectioned fine stainless steel wires. The procedure for preparing such filters, in which only the fused part, which arises from the crushing of the wire edges, possesses a large net area and the metal is diffused into the fused part, is achieved by heating and compressing the system simultaneously.

Inventors

  • 👤 Takashi Oda
  • 👤 Kaoru Kokubu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 16:32
CPC Classifications
B; B01; B01D; B01D39/00; B01D39/14; B01D39/20; B01D39/2027; B01D39/2041; B01D39/2044; B22; B22F; B22F3/00; B22F3/002

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 77 words
In a method of preparing a filter of the type comprising a plurality of fine wires having a polygonal cross-section with an area of fusion between the wires at the points of contact therebetween, the improvement which comprises: (a) heating the plurality of wires in a furnace, (b) simultaneously with the heating, compressing the wires to create a fusion between the wires at the points of contact therebetween, and (c) thereafter, cooling the heated and compressed wires.
Claim 2
Dependent Claim 77 words
In a method of preparing a filter of the type comprising a plurality of fine wires having a polygonal cross-section with an area of fusion between the wires at the points of contact therebetween, the improvement which comprises: (a) heating the plurality of wires in a furnace, (b) simultaneously with the heating, compressing the wires to create a fusion between the wires at the points of contact therebetween, and (c) thereafter, cooling the heated and compressed wires.
Claim 3
Dependent Claim 12 words
The improvement of claim 1 wherein: the wires are stainless steel wires.
Claim 4
Dependent Claim 16 words
The improvement of claim 2 wherein: the wires are heated and compressed in an inert atmosphere.
Claim 5
Dependent Claim 14 words
The improvement of claim 2 wherein: the wires are heated and compressed under vacuum.
Claim 6
Dependent Claim 51 words
The improvement of claim 2 wherein: the plurality of wires are disposed in overlying first and second arrays, the first array being defined by a plurality of layers of the wires, each layer comprising a regular network of interwoven wires, and the second array being defined by an interwoven irregular web.
Claim 7
Dependent Claim 43 words
The improvement of claim 5 which further comprises: a third array, the third array being defined by a plurality of layers, each layer comprising a regular network of interwoven wires, and wherein the second array is sandwiched between the first and third arrays.
Claim 8
Dependent Claim 17 words
The improvement of claim 1 wherein: the furnace is maintained at a temperature of about 900° C.
Claim 9
Dependent Claim 25 words
The improvement of claim 1 wherein: the wires are compressed at a pressure of from about 20 kg/m 2 to about 30 kg/m 2 .

References Cited (Backward Citations)

US3690606A Cited
US3780872A Cited
US3693750A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-10-23 1982-04-24 1982-10-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-10-23 1986-04-24 1986-10-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-10-23 1990-04-24 1990-10-24 $7700.00 Window Closed / Lapsed

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