Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
404 words
A device for limiting the dynamic pressure in an engine exhaust brake wherein a valve is provided in an exhaust pipe, the exhaust pipe having an internal circular cross-section, comprising: a butterfly disc valve having a substantially elliptically shaped peripheral edge in the exhaust pipe; means for pivotally mounting said butterfly disc valve in the exhaust pipe for pivotal movement about a pivotal axis between an open position wherein said disc valve allows fluid flow through said exhaust pipe past said disc valve and a closed position wherein said disc valve is substantially oblique relative to the diameter of the exhaust pipe and said peripheral edge substantially engages the inner surface of the exhaust pipe to substantially restrict fluid flow therethrough; and a pressure relief poppet valve on said exhaust pipe comprising a poppet valve housing, a poppet valve bore in said housing having an inner end communicating with the interior of the exhaust pipe at a position extending over a portion of said peripheral edge of said disc valve when said disc valve is in the closed position to provide a by-pass for fluid flow at said inner end, said bore having an axis extending in a direction offset with respect to said pivotal axis of said disc valve, a poppet valve head slidably mounted in said bore for movement between an open position remote from said inner end of said bore and a closed position adjacent the inner surface of said exhaust pipe, an inner end face on said poppet valve head having a configuration substantially conforming to the curvature of the inner surface of the exhaust pipe, said configuration and position of said inner end face relative to said inner end of said bore when said poppet valve head is in said closed position providing a narrow gap between said inner end face and said portion of said peripheral edge of said valve disc adjacent said inner end of said bore when said poppet valve head and said valve disc are both in the respective closed positions thereof to allow by-pass flow of fluid therethrough for limiting dynamic pressure in the exhaust pipe, and spring means between said poppet valve head and said housing resiliently urging said poppet valve head toward said closed position, said spring means having a linear spring characteristic comprising a ratio of spring force N to spring deflection in mm in the range of 1.5-2.5 to 1.
Claim 2
Independent Claim
404 words
A device for limiting the dynamic pressure in an engine exhaust brake wherein a valve is provided in an exhaust pipe, the exhaust pipe having an internal circular cross-section, comprising: a butterfly disc valve having a substantially elliptically shaped peripheral edge in the exhaust pipe; means for pivotally mounting said butterfly disc valve in the exhaust pipe for pivotal movement about a pivotal axis between an open position wherein said disc valve allows fluid flow through said exhaust pipe past said disc valve and a closed position wherein said disc valve is substantially oblique relative to the diameter of the exhaust pipe and said peripheral edge substantially engages the inner surface of the exhaust pipe to substantially restrict fluid flow therethrough; and a pressure relief poppet valve on said exhaust pipe comprising a poppet valve housing, a poppet valve bore in said housing having an inner end communicating with the interior of the exhaust pipe at a position extending over a portion of said peripheral edge of said disc valve when said disc valve is in the closed position to provide a by-pass for fluid flow at said inner end, said bore having an axis extending in a direction offset with respect to said pivotal axis of said disc valve, a poppet valve head slidably mounted in said bore for movement between an open position remote from said inner end of said bore and a closed position adjacent the inner surface of said exhaust pipe, an inner end face on said poppet valve head having a configuration substantially conforming to the curvature of the inner surface of the exhaust pipe, said configuration and position of said inner end face relative to said inner end of said bore when said poppet valve head is in said closed position providing a narrow gap between said inner end face and said portion of said peripheral edge of said valve disc adjacent said inner end of said bore when said poppet valve head and said valve disc are both in the respective closed positions thereof to allow by-pass flow of fluid therethrough for limiting dynamic pressure in the exhaust pipe, and spring means between said poppet valve head and said housing resiliently urging said poppet valve head toward said closed position, said spring means having a linear spring characteristic comprising a ratio of spring force N to spring deflection in mm in the range of 1.5-2.5 to 1.
Claim 3
Dependent Claim
27 words
A device as claimed in claim 1 wherein: said inner end face configuration of said poppet valve head comprises a segment of a substantially spherical concave surface.
Claim 4
Dependent Claim
98 words
A device as claimed in claim 1 wherein: said poppet valve bore has a stepped configuration comprising two sections of different diameters and a shoulder between said two sections; and said poppet valve head has a stepped configuration on the outer surface thereof comprising two sections of different outer diameters conforming respectively to said different diameters of said bore, and a shoulder on said outer surface between said different outer diameters; said shoulders being engaged for limiting travel of said poppet valve head and providing said narrow gap when said poppet valve head is in the closed position.
Claim 5
Dependent Claim
98 words
A device as claimed in claim 2 wherein: said poppet valve bore has a stepped configuration comprising two sections of different diameters and a shoulder between said two sections; and said poppet valve head has a stepped configuration on the outer surface thereof comprising two sections of different outer diameters conforming respectively to said different diameters of said bore, and a shoulder on said outer surface between said different outer diameters; said shoulders being engaged for limiting travel of said poppet valve head and providing said narrow gap when said poppet valve head is in the closed position.
Claim 6
Dependent Claim
16 words
A device as claimed in claim 1 wherein: said spring means comprises a compression coil spring.
Claim 7
Dependent Claim
16 words
A device as claimed in claim 4 wherein: said spring means comprises a compression coil spring.
Claim 8
Dependent Claim
43 words
A device as claimed in claim 1 wherein: said means for pivotally mounting said butterfly disc valve comprises a shaft rotatably mounted in the exhaust pipe and having a central longitudinal axis coinciding with a diameter of the interior of the exhaust pipe.
Claim 9
Dependent Claim
43 words
A device as claimed in claim 6 wherein: said means for pivotally mounting said butterfly disc valve comprises a shaft rotatably mounted in the exhaust pipe and having a central longitudinal axis coinciding with a diameter of the interior of the exhaust pipe.
Claim 10
Dependent Claim
37 words
A device as claimed in claim 7 wherein: said axis of said bore extends substantially diametrically relative to the interior of the exhaust pipe and substantially perpendicularly to the plane containing said central axis of said shaft.
Claim 11
Dependent Claim
37 words
A device as claimed in claim 8 wherein: said axis of said bore extends substantially diametrically relative to the interior of the exhaust pipe and substantially perpendicularly to the plane containing said central axis of said shaft.