Pipe joints or couplings – Ball and socket – Spring-biased ball
Reexamination Certificate
2000-03-27
2001-11-06
Browne, Lynne H. (Department: 3629)
Pipe joints or couplings
Ball and socket
Spring-biased ball
C285S334400, C277S626000
Reexamination Certificate
active
06312022
ABSTRACT:
This invention relates to pipe joints employing spherical seals for automotive exhaust systems.
Of interest is commonly owned U.S. Pat. No. 5,683,119 incorporated by reference herein.
U.S. Pat. No. 3,165,339 discloses a swivel pipe coupling. However, this coupling is for low temperature fluids, e.g., liquids at minus 300° F. (−185° C.). This coupling employs a thermoplastic sealing ring which is not acceptable for high temperature exhaust gases.
Pipe joints for certain automotive exhaust systems employ seals with spherical surfaces. For example, prior art joints and seals are disclosed in U.S. Pat. Nos. 5,499,825 and 5,040,805, incorporated by reference herein. Typical exhaust joints comprise a seal, usually formed into a preform of a wire mesh and filler material, and then crushed by dies to the end seal shape as illustrated in the aforementioned patents. The seals may be rigid or compliant in accordance with the seal construction. A lubricant or lubricating material is incorporated in the seal to provide a lubricating surface.
The seals are annular with a radially outer convex spherical segment surface and opposing planar end surfaces as shown in U.S. Pat. No. 5,499,825. In this patent, circular cylindrical through bore communicates with the planar end surfaces for receiving a pipe concentric with the spherical annular surface. A flange is welded in fixed position to the received pipe spaced from the pipe end edge and has a planar surface abutting one of the seal planar surfaces. The flange fixes the axial position of the seal. The seal spherical surface terminates adjacent to the flange. The other planar surface of the seal terminates approximately flush with the pipe end edge. The seal thus has an annular bore surface abutting the pipe outer circumference and a circular disc-like plane surface normal to the bore abutting the flange.
A second movable flange has a concave surface mating with the seal convex surface to form a dynamic engagement therewith. The two flanges each have a pair of aligned apertured flange members. A bolt is screwed to the flange members of the fixed flange. A compression spring is between each flange member of the movable flange and captured to the bolt by a bolt head. The springs resiliently urge the dynamic flange concave surface in engagement with the seal convex surface.
A second pipe is secured to the dynamic flange. The second pipe thus can resiliently rotate relative to the first pipe about the engaged spherical surfaces. A similar joint is illustrated in U.S. Pat. No. 5,040,805. The purpose of these joints is to provide a relatively fluid tight seal for exhaust gases conducted through the pipes at the joint while permitting the pipes to move relative to one another.
Numerous other joints are known as disclosed in prior art patents which combine planar surfaces with spherical or inclined surfaces. For example, reference is made to U.S. Pats. Nos. 4,097,071, 4,133,558, 4,223,922, 4,452,474, 4,583,768, 4,928,998 among others.
The present inventors recognize a problem with the exhaust gas joints. They recognize that in such prior art joints the cylindrical and planar mating surfaces in abutment together do not provide a sufficiently fluid tight seal for the exhaust gases at the interface of the two joined pipes. They recognize that the fixed flange and mating pipe cylindrical mating surfaces and the flat surface of the seal with the mating flat flange surface provide a relatively high gas leakage path.
The aforementioned patent U.S. Pat. No. 5,683,119 solves the problems with these prior art joints. However, a need is seen for a less costly and more compact seal assembly for such exhaust systems.
A pipe joint and seal according to the present invention comprises a first flange for attachment to a first pipe and having a concave spherical inner surface defined by a first radius of a first magnitude. A second flange is for attachment to a second pipe and has a convex spherical outer surface defined by a second radius of a second magnitude. An annular seal has an outer convex spherical surface engaged with the first flange concave inner surface, the outer convex spherical surface of the seal being defined by a third radius of a third magnitude smaller than the first radius magnitude, the seal having an inner concave spherical surface engaged with the second flange convex outer surface and defined by a fourth radius larger than the second flange convex outer second radius.
In one aspect, the seal comprises compressed wire mesh and a filler material.
In a further aspect, means rigidly connect the first and second flanges to each other.
In a still further aspect, means movably connect the first and second flanges to each other.
Preferably, the first and second pipes are included and include means for securing the first pipe to the first flange and the second pipe to the second flange.
In a further aspect, the seal includes an annular ridge extending radially outwardly from the outer convex surface radially aligned with the inner concave surface. The seal may have an inner annular bore surface adjacent to the inner concave surface and radially aligned with the outer convex surface.
The ridge is preferably intermediate the first and second flanges. In a further aspect, the seal outer convex surface is tangent to the first flange concave inner surface at a first point and the inner concave surface of the seal is tangent to the second flange convex outer surface at a second point, the points of tangency being radially offset from each other.
REFERENCES:
patent: 3165339 (1965-01-01), Faccou
patent: 3258278 (1966-06-01), Miller, Jr.
patent: 4097071 (1978-06-01), Crawford et al.
patent: 4133558 (1979-01-01), Ahlstone
patent: 4223922 (1980-09-01), Pape
patent: 4452474 (1984-06-01), Hanger
patent: 4583768 (1986-04-01), Aoki et al.
patent: 4881759 (1989-11-01), Kovitch et al.
patent: 4893847 (1990-01-01), Hess
patent: 4928998 (1990-05-01), Brandener
patent: 5203593 (1993-04-01), Brandener
patent: 5393108 (1995-02-01), Kerr
patent: 5683119 (1997-11-01), Emmons et al.
patent: 5779282 (1998-07-01), Ezze
patent: 5966932 (1999-10-01), Yahagi
Brophy, III Lawrence John
Emmons Kurry Brian
Browne Lynne H.
Carelin Byrne Bain Gilfillan et al.
Gilfillan III John G.
Metex Mfg. Corporation
Squire William
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