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US4881474A Expired / Lapsed US ⏱️ 0.0 years remaining

Pulverized coal combustion apparatus

Assignee: Mitsubishi Power Ltd
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Filing: 1988-10-05
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Granted: 1989-11-21
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Expires: 2008-10-05
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Abstract

Abstract A pulverized coal combustion apparatus comprises a burner through which pulverized coal and carrier air are passed to be burnt in a combustion chamber, and a flame retainer disposed at an end of the burner. The flame retainer includes a flared tube and an annular plate, which plate has a plurality of radially inwardly projecting parts equiangularly spaced from each other. The annular plate comprises a plurality of ceramic pieces and a plurality of fastener elements, both of which are arranged and assembled alternately to form the annular plate. Each ceramic piece is so shaped that it projects radially inwardly to serve as the projecting part when assembled. The ceramic piece has at opposite sides thereof smoothly curved edge surfaces, and the fastener element has at opposite sides thereof smoothly curved edge surfaces which are engaged with the curved edge surfaces of neighboring two ceramic pieces.

Inventors

  • 👤 Osamu Okada
  • 👤 Shigeki Morita
  • 👤 Shigeto Nakashita
  • 👤 Tadahisa Masai
  • 👤 Shigeru Tominaga
  • 👤 Hiroshi Inada

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 10:12
CPC Classifications
F; F23; F23D; F23D1/00; F23D2201/00; F23D2201/10

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 152 words
A pulverized coal combustion apparatus comprising a burner through which pulverized coal and carrier medium are passed to be burnt in a combustion chamber, and a flame retainer disposed at an end of said burner, said flame retainer including a flared tube and an annular plate, which plate has a plurality of radially inwardly projecting parts equiangularly spaced from each other, wherein said annular plate comprises a plurality of ceramic pieces and a plurality of fastener elements, both of which are arranged and assembled alternately to form said annular plate, said ceramic piece being so shaped that is projects radially inwardly to serve as said projecting part when assembled, and said ceramic piece having at opposite sides thereof smoothly curved edge surfaces, and said fastener element having at opposite sides thereof smoothly curved edge surfaces which are engaged with the curved edge surfaces of neighboring two ceramic pieces of said ceramic pieces.
Claim 2
Dependent Claim 152 words
A pulverized coal combustion apparatus comprising a burner through which pulverized coal and carrier medium are passed to be burnt in a combustion chamber, and a flame retainer disposed at an end of said burner, said flame retainer including a flared tube and an annular plate, which plate has a plurality of radially inwardly projecting parts equiangularly spaced from each other, wherein said annular plate comprises a plurality of ceramic pieces and a plurality of fastener elements, both of which are arranged and assembled alternately to form said annular plate, said ceramic piece being so shaped that is projects radially inwardly to serve as said projecting part when assembled, and said ceramic piece having at opposite sides thereof smoothly curved edge surfaces, and said fastener element having at opposite sides thereof smoothly curved edge surfaces which are engaged with the curved edge surfaces of neighboring two ceramic pieces of said ceramic pieces.
Claim 3
Dependent Claim 49 words
An apparatus according to claim 1, wherein said fastener element further comprises at opposite sides thereof flange portions integrally formed on said fastener element, each of said flange portions being engaged with an axial end surface of the neighboring ceramic piece, which end surface faces to said combustion chamber.
Claim 4
Dependent Claim 26 words
An apparatus according to claim 1, wherein said retainer further comprises a ceramic ring disposed within said annular plate, with which said annular plate is lined.

References Cited (Backward Citations)

US4333405A Cited
US4321034A Cited
US4422389A Cited
US4748919A Cited
US4545307A Cited
US4602571A Cited
US4726760A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-11-20 1993-05-22 1993-11-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-11-20 1997-05-22 1997-11-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-11-20 2001-05-22 2001-11-21 $7700.00 Window Closed / Lapsed

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