EP0453315A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Brush seals
Assignee: Cross Manufacturing Co 1938 Ltd
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Filing: 1991-04-19
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Granted: —
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Expires: 2011-04-19
Abstract
Abstract A brush seal element has an annular base plate (15) for mounting on a housing (12) defining a bore (11) through which extends a rotatable shaft (13). The base plate (15) carries a plurality of bristles (14) projecting towards the shaft, the tips (23) of the bristles wiping against the circumferential shaft surface (24) to effect a seal thereagainst. An annular backing plate (16) supports the bristles on the low-pressure side of the seal to resist axial flexing of the bristles, the edge (18) of the backing plate (16) nearest the shaft being coated with an abradable material (19). Clearance between the shaft (13) and the backing plate (16) may be maintained at a minimum, to give maximum support to the bristles, but should the shaft perform large radial excursions, the abradable material (19) will rub away without causing seal failure.
Inventors
- 👤 Ralph Franklyn John Flower
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 05:45
CPC Classifications
F; F16; F16J; F16J15/00; F16J15/16; F16J15/32; F16J15/3284; F16J15/3288
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
167 words
A brush seal for effecting a seal between a shaft (13) and a housing (12) having a bore (11) through which the shaft extends, which seal comprises a base portion (15) for mounting on one of said shaft and said housing, a plurality of bristles (14) projecting from the base portion and having tip portions (23) for wiping against a surface (24) of the other of said shaft and said housing, and a backing plate (16) projecting from the base portion part-way towards said tip portions of the bristles, which backing plate is disposed to support the bristles against flexing towards the backing plate in a direction generally parallel to the shaft axis, characertised in that an abradable material (19) is provided on the backing plate (16) which abradable material projects towards the said tip portions (23) of the bristles (14) from the edge of the backing plate adjacent said tip portions, which abradable material (19) is disposed to support said tip portions (23) of the bristles.
Claim 2
Dependent Claim
19 words
A brush seal according to claim 1, characterised in that said abradable material (19) comprises a low-friction nickel-graphite alloy.
Claim 3
Dependent Claim
53 words
A brush seal according to claim 1 or claim 2, characterised in that said abradable material (19) has a cylindrical face nearest the tip portions of the bristles, the width of said face in the axial direction having a lesser dimension than the cross-sectional thickness of said backing plate (Figures 2 or 3).
Claim 4
Dependent Claim
22 words
A brush seal according to claim 3, characterised in that said abradable material (19) has a tapering profile, in the radial direction.
Claim 5
Dependent Claim
31 words
A brush seal according to claim 4, characterised in that the cross-sectional thickness of said backing plate (16) tapers in a corresponding manner to the taper of the abradable material (19).
Claim 6
Dependent Claim
53 words
A brush seal according to claim 1, characterised in that said backing plate (16) has at least two axially spaced arms (27) extending generally radially, one of said arms being arranged to support the tip portions of the bristles, (14) and the ends of each arm being provided with said abradable material (28,29,30).
Claim 7
Dependent Claim
70 words
A brush seal according to any of the preceding claims, wherein the base portion (15) is in the form of an annular plate, the backing plate (16) also is annular and has a greater radial extent than that of said base plate, and the plurality of bristles (14) are mounted between the base plate (15) and the backing plate (16), with the bristle tip portions projecting beyond the backing plate.
Claim 8
Dependent Claim
27 words
A brush seal assembly comprising at least two brush seals each of which accords to any of one of claims 1 to 7 and arranged co-axially side-by-side.
Claim 9
Dependent Claim
174 words
A brush seal assembly comprising a housing (12) defining a bore (11), a shaft (13) rotatably mounted within the housing (12) and extending through the bore, a brush seal element (10) mounted on the housing to surround the shaft and effect a seal between the shaft and the housing, which said brush seal element comprises: - an annular base portion (15); - a plurality of bristles (14) projecting from the base portion and having tip portions (23) remote from said base portion which tip portions wipe against a circumferential surface of said shaft; - an annular backing plate (16) projecting from the base portion towards said bristle tip portions (23) and disposed to support the bristles against flexing in the axial direction towards said plate; characterised in that the backing plate (16) is provided with an abradable material disposed on the face thereof nearest said shaft (13) and disposed to support said bristle tip portions, and in that said circumferential shaft surface is provided with a rubbing surface (24) for said bristle tip portions.
Claim 10
Dependent Claim
25 words
A brush seal assembly according to claim 9, in which said shaft rubbing surface (24) comprises a coating of aluminium oxide or of chromium carbide.
References Cited (Backward Citations)
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