Back pressure regulator for automotive engines

Claim 1

A device for attachment to the discharge end of an exhaust conduit of an internal combustion engine to restrict a passing exhaust flow, said device comprising, a molded body of heat resistant elastomeric material having a forward segment of cylindrical shape for the reception of the exhaust conduit, said forward segment longitudinally slotted for a portion of its length, said body having a central segment with elliptical internal wall surfaces and walls of uniform thickness converging in the direction of exhaust flow resulting in the central segment being of lesser internal sectional area than the sectional area of the exhaust conduit, said body having a rearward segment with opposed walls having substantially parallel internal wall surfaces, in the absence of exhaust flow, terminating in an elongate orifice at the rearward end of said body, said orifice being of substantially less section area than the exhaust conduit to thereby constitute a restriction to the exhaust flow, said body and particularly the walls of said rearward section being responsive to various exhaust pressures to exert a desired restrictive effect on the exhaust flow, said body adapted for repositioning forwardly along the exhaust conduit whereby the conduit end will mechanically bias the internal walls of the central segment away from one another to reduce the restrictive effect of the device on an exhaust flow, and clamping means circumposed about the molded body and retaining same at a selected position relative to the end of the exhaust conduit.

Claim 2

A device for attachment to the discharge end of an exhaust conduit of an internal combustion engine to restrict a passing exhaust flow, said device comprising, a molded body of heat resistant elastomeric material having a forward segment of cylindrical shape for the reception of the exhaust conduit, said forward segment longitudinally slotted for a portion of its length, said body having a central segment with elliptical internal wall surfaces and walls of uniform thickness converging in the direction of exhaust flow resulting in the central segment being of lesser internal sectional area than the sectional area of the exhaust conduit, said body having a rearward segment with opposed walls having substantially parallel internal wall surfaces, in the absence of exhaust flow, terminating in an elongate orifice at the rearward end of said body, said orifice being of substantially less section area than the exhaust conduit to thereby constitute a restriction to the exhaust flow, said body and particularly the walls of said rearward section being responsive to various exhaust pressures to exert a desired restrictive effect on the exhaust flow, said body adapted for repositioning forwardly along the exhaust conduit whereby the conduit end will mechanically bias the internal walls of the central segment away from one another to reduce the restrictive effect of the device on an exhaust flow, and clamping means circumposed about the molded body and retaining same at a selected position relative to the end of the exhaust conduit.

Claim 3

A device for attachment to the discharge end of an exhaust conduit of an internal combustion engine to restrict a passing exhaust flow, said device comprising, a molded body of heat resistant elastomeric material having a forward segment of cylindrical shape for the reception of the exhaust conduit, said forward segment longitudinally slotted for a portion of its length, said body having a central segment with elliptical internal wall surfaces and walls of uniform thickness converging in the direction of exhaust flow resulting in the central segment being of lesser internal sectional area than the sectional area of the exhaust conduit, said body having a rearward segment with opposed walls having substantially parallel internal wall surfaces, in the absence of exhaust flow, terminating in an elongate orifice at the rearward end of said body, said orifice being of substantially less section area than the exhaust conduit to thereby constitute a restriction to the exhaust flow, said body and particularly the walls of said rearward section being responsive to various exhaust pressures to exert a desired restrictive effect on the exhaust flow, said body adapted for repositioning forwardly along the exhaust conduit whereby the conduit end will mechanically bias the internal walls of the central segment away from one another to reduce the restrictive effect of the device on an exhaust flow, and clamping means circumposed about the molded body and retaining same at a selected position relative to the end of the exhaust conduit.

Claim 4

A device for attachment to the discharge end of an exhaust conduit of an internal combustion engine to restrict a passing exhaust flow, said device comprising, a molded body of heat resistant elastomeric material having a forward segment of cylindrical shape for the reception of the exhaust conduit, said forward segment longitudinally slotted for a portion of its length, said body having a central segment with elliptical internal wall surfaces and walls of uniform thickness converging in the direction of exhaust flow resulting in the central segment being of lesser internal sectional area than the sectional area of the exhaust conduit, said body having a rearward segment with opposed walls having substantially parallel internal wall surfaces, in the absence of exhaust flow, terminating in an elongate orifice at the rearward end of said body, said orifice being of substantially less section area than the exhaust conduit to thereby constitute a restriction to the exhaust flow, said body and particularly the walls of said rearward section being responsive to various exhaust pressures to exert a desired restrictive effect on the exhaust flow, said body adapted for repositioning forwardly along the exhaust conduit whereby the conduit end will mechanically bias the internal walls of the central segment away from one another to reduce the restrictive effect of the device on an exhaust flow, and clamping means circumposed about the molded body and retaining same at a selected position relative to the end of the exhaust conduit.