Vehicular muffler with improved mechanical lock joints

An improved muffler for a vehicular exhaust system used with an internal combustion engine comprising:

• A. a reversing unit sub-assembly having first and second ends and comprising:
• a first panel having first and second, oppositely facing side surfaces, a peripheral edge, an aperture, an aperture flange that surrounds the first panel aperture and that projects perpendicularly from the plane of the first panel, and a peripheral flange that is disposed adjacent to the peripheral edge of the first panel and that projects perpendicularly from one of the side surfaces of the first panel, with the first panel being disposed adjacent to the first end of the reversing unit sub-assembly so that the first surface of the first panel faces the first end of the reversing unit sub-assembly and so that the second surface of the first panel faces the second end of the reversing unit sub-assembly;
• a flow tube having first and second ends, with the first end of the flow tube extending into and through the first panel aperture so that the leading end of the first end of the flow tube is adjacent to the first surface of the first panel and so that the second end of the flow tube is adjacent to the second surface of the first panel, and with the first end of the flow tube having pre-selected inner diameter;
• and
• first means for mechanically locking the first end of the flow tube in the first panel aperture;
• B. an inner sheet metal wrapper having an inner surface, an outer surface, a first side edge, a second side edge, and first and second end edges that are joined together, with the inner wrapper being configured so that the reversing unit sub-assembly is disposed within the inner wrapper, so that the inner wrapper extends around the peripheral edge of the first panel, so that the inner surface of the inner wrapper is in contact with but is metallurgically unbonded to the peripheral flange of the first panel, and so that the first panel is adjacent to the first side edge of the inner wrapper;
• C. an outer sheet metal wrapper having an inner surface, an outer surface, a first side edge, second side edge and first and second end edges that a rejoined together, with the outer wrapper extending around the inner wrapper so that its inner surface is adjacent to the outer surface of the inner wrapper, so that its first and second side edges are adjacent to the first and second side edges, respectively, of the inner wrapper and so that the outer surface of the outer wrapper serves as the outer surface of the muffler;
• D. a first end cap sub-assembly that is assembled onto the first end of the assembled reversing unit sub-assembly, inner wrapper and outer wrapper, with the first cap sub-assembly including:
• a first end panel having a first side surface, a second side surface, a peripheral edge that is adjacent to the first side edges of the inner and outer wrappers, an aperture in the first end panel, an aperture flange that surrounds the first end panel aperture and that projects perpendicularly from the plane of the first side surface of the first end panel;
• a first end tube that has first and second ends and that is disposed, between its ends, within the first end panel aperture with the first end of the first end tube having a preselected outer diameter so that the first end of the first end tube fits loosely telescopically and overlappingly within the first end of the first flow tube so as to minimize the possibility that forces applied in assembling the first end cap sub-assembly onto the first end of the reversing unit sub-assembly will cause axial displacement of the first panel relative to the inner wrapper;
• E. second means for mechanically locking the first end tube within the first end panel aperture;
• F. third means for mechanically locking together the overlapped first ends of the first end tube and the first flow tube;
• the third mechanical locking means including a circumferential, continuous, series of zig-zag arranged beads in the overlapped ends of the first end tube and the first flow tube, where the one ends of the zig-zag beads extend beyond the surface of the first panel, where the other ends of the zig-zag beads extend beyond the distal end of the first panel aperture flange, and where the zig-zag beads maintain the relative axial positions of the overlapped ends and resist relative movement between the overlapped ends due to the application of torsional and axial forces that the tubes experienced during fabrication of the muffler and during assembly of the muffler with the vehicular exhaust system;
• and
• G. fourth means for joining the first side edge of the outer wrapper and the peripheral edge of the first end panel.

An improved muffler for a vehicular exhaust system used with an internal combustion engine comprising:

• a wrapper having an inner surface, first and second end edges that are joined together, and first and second side edges, with the body being configured so that its inner surface defines a volume, between its first and second side edges, having a predetermined cross-sectional configuration;
• a first panel having a peripheral edge generally congruent with the predetermined cross-sectional configuration, a peripheral flange that extends about the peripheral edge and that projects perpendicularly from the adjacent plane of the first panel, an aperture, and an aperture flange that surrounds the first panel aperture and that projects perpendicularly from the adjacent plane of the first panel, with the first panel being disposed within the volume defined by the inner surface of the wrapper so that the inner surface of the wrapper is in contact with but is metallurgically unbonded to the panel flange;
• a first flow tube disposed, at least in part, within the volume defined by the wrapper and having a first end that is disposed within and extends through the first panel aperture, with the first end of the first tube having a preselected inner diameter;
• a first end tube that extends from without to within the volume defined by the wrapper and between the first side edge of the body wrapper and that has a first end, with the outer diameter of the first end of the first end tube being preselected, with respect to the inner diameter of the first end of the first flow tube so that the first end of the first end tube fits loosely, telescopically and overlappingly within the first end of the first flow tube during assembly of the first end of the end tube into the first end of the first flow tube so as to minimize the possibility that forces applied in assembling the first end of the first end tube into the first end of the first flow tube and in handling and using the muffler will cause axial displacement of the first panel relative to the wrapper, with the leading end of the first end of the first end tube extending within the first end of the first flow tube to a point beyond the plane of the first panel;
• and
• first means for mechanically locking together the overlapped first end of the first end tube and the first end of the first flow tube so as to maintain the relative axial positions of the overlapped ends and to resist relative movement between the overlapped ends due to the application of torsional and axial forces that the tubes experience during the fabrication of the muffler and during assembly of the muffler with the vehicular exhaust system.

An improved muffler for a vehicular exhaust system used with an internal combustion engine comprising:

• a wrapper having an inner surface, first and second end edges that are joined together, and first and second side edges, with the body being configured so that its inner surface defines a volume, between its first and second side edges, having a predetermined cross-sectional configuration;
• a first panel having a peripheral edge generally congruent with the predetermined cross-sectional configuration, a peripheral flange that extends about the peripheral edge and that projects perpendicularly from the adjacent plane of the first panel, an aperture, and an aperture flange that surrounds the first panel aperture and that projects perpendicularly from the adjacent plane of the first panel, with the first panel being disposed within the volume defined by the inner surface of the wrapper so that the inner surface of the wrapper is in contact with but is metallurgically unbonded to the panel flange;
• a first flow tube disposed, at least in part, within the volume defined by the wrapper and having a first end that is disposed within and extends through the first panel aperture, with the first end of the first tube having a preselected inner diameter;
• an end tube that extends from without to within the volume defined by the wrapper and between the first side edge of the body wrapper, with the end tube having a first end that has a preselected outer diameter so that the first end of the end tube fits loosely, telescopically and overlappingly within the first end of the first tube so as to minimize the possibility that forces applied in assembling the first ends will cause axial displacement of the first panel relative to the wrapper, with the leading end of the first end of the end tube extending within the first end of the first flow tube to a point beyond the plane of the first panel;
• and
• first means for mechanically locking together the overlapped first end of the end tube and the first end of the flow tube so as to maintain the relative axial positions of the overlapped ends and to resist relative movement between the overlapped ends due to the application of torsional and axial forces that the tubes experience during the fabrication of the muffler and during assembly of the muffler with the vehicular exhaust system, the first mechanical locking means including a circumferential, continuous, series of zig-zag arranged beads in the overlapped ends of the first end tube and the first flow tube, where the one ends of the zig-zag beads extend beyond the surface of the first panel, where the other ends of the zig-zag beads extend beyond the distal end of the first panel aperture flange, and where the zig-zag beads maintains the relative axial positions of the overlapped ends and resist relative movement between the overlapped ends due to the application of torsional and axial forces that the tubes experience during fabrication of the muffler and during assembly of the muffler with the vehicular exhaust system.

In a muffler for a vehicular exhaust system used with an internal combustion engine and including:

• an internal panel having a first and second oppositely facing side surfaces and an aperture, a flange that surrounds the internal panel aperture and that projects perpendicularly from the plane of the internal panel;
• a flow tube having a first end and a second end, with the first end having a preselected inner diameter, the improvement comprising:
• means for mechanically locking the first end of the flow tube in the internal panel aperture so that the first end of the flow tube extends through the internal panel aperture, so that the leading edge of the first end of the flow tube is adjacent to the first surface of the internal panel, and so that the second end of the flow tube is adjacent to the second surface of the internal panel, an end tube having a first end whose outer diameter is preselected, with respect to the inner diameter of the first end of the flow tube, such that the first end of the end tube loosely, telescopically and overlappingly fits within the first end of the flow tube;
• a circumferential skewed bead in the overlapped first ends of the flow tube and end tube, where the plane of the skewed bead is at an angle less than ninety degrees with respect to the central longitudinal axes of the overlapped ends of the tubes, and where skewed bead maintains the relative axial positions of the overlapped ends and resists relative movement between the overlapped ends due to the application of torsional and axial forces that the tubes experience during the assembly of the muffler.

An improved muffler for a vehicular exhaust system used with an internal combustion engine and including:

• a panel having a first and second oppositely facing side surfaces and an aperture having a preselected inner diameter;
• a flange that surrounds the panel aperture, that has a preselected inner diameter substantially identical to the preselected inner diameter of the aperture, and that projects perpendicularly from the plane of the first side surface of the panel;
• a flow tube having a first end, with the first end having a preselected outer diameter so that the first end of the flow tube may be fit within the panel aperture and panel aperture flange, and with the first end of the flow tube being disposed in the panel aperture so that the panel aperture flange overlaps a portion of the flow tube adjacent to the first end of the flow tube;
• an end tube having a first end, with the first end of the end tube having a preselected outer diameter so that the first end of the tube may fit within the first end of the flow tube and so that the portion of the flow tube overlaps the first end of the end tube;
• means for mechanically locking the first end of the flow tube and the first end of the end tube together and within the panel aperture and panel aperture flange, the mechanical locking means including a continuous, circumferential, skewed bead in the panel and in the overlapped panel aperture flange flow tube and end tube, the bead extending beyond the second side surface of the panel, on one side, and beyond the distal end of the panel aperture flange, on the other side, with the plane of the skewed bead being at an angle of less than ninety degrees with respect to the central longitudinal axis of the flow tube;
• and with the skewed bead maintaining the relative axial positions of the panel, the end tube and the flow and resisting relative axial and rotational movement between the panel, the end tube and the flow tube due to the application of torsional and axial forces that the tubes experience during the fabrication of the muffler and during assembly of the muffler with the vehicular exhaust system.

In a muffler for a vehicular exhaust system used with an internal combustion engine, with the muffler including:

• an end panel having a first and second oppositely facing side surfaces and an aperture therethrough and having a flange that surrounds the aperture and that projects perpendicularly from the plane of the first surface of the end panel, the improvement including:
• an end tube that extends through the end panel aperture and the aperture flange, that has a preselected outer diameter portion so that the portion of the end tube fits loosely within the end panel aperture and the aperture flange, and that has a longitudinal central axis;
• and
• means for mechanically locking the end tube portion and the end panel, the mechanical locking means including a continuous, circumferential bead in the part of the end tube portion adjacent to the second surface of the end panel, where the plane of the circumferential bead is disposed at an angle of ninety degrees with respect to the longitudinal axis of the end tube;
• and a plurality of spaced apart, circumferential, aligned, elongated, non-spherical deformations in the overlapped part of the end tube portion and the end panel aperture flange, with each of the elongated deformations each having major longitudinal axes, and where the planes of these elongated deformations, which planes include their longitudinal axes, are disposed at an angle of ninety degrees with respect to the longitudinal central axis of the end tube.