Abstract: A combined catalytic converter and muffler is provided. A catalyst is securely mounted in a canister which in turn is mounted intermediate a pair of formed internal plates. The plates are further formed to define an array of tubes therebetween. The tubes comprise an inlet to the muffler and an outlet from the muffler and communicate with the inlet and outlet of the catalytic converter. Selected tubes may have perforations or other apertures through which exhaust gases may communicate. At least one external shell is mounted to the assembled internal plates. The external shell is formed to define a plurality of chambers which communicate with apertures in the internal plates.

Abstract: Stamped formed mufflers and a process for forming stamped formed mufflers is provided. The mufflers are stamp formed from master dies having a plurality of die subsets removably mounted therein. At least one subset may include several die inserts removably mounted therein. The subset and insert dies are selected to effect the acoustical performance of the resulting muffler. Thus, a system of mufflers may be formed having generally the same pattern of tubes therein. However, selected mufflers in the system will have portions thereof which are different from other mufflers in the system, depending upon the particular die subsets selected for mounting in the master die, and the particular die inserts selected for mounting in the subsets.

Abstract: A stamp formed muffler comprising a pair of internal plates and a pair of external shells is provided. The internal plates are stamp formed to define first and second spaced apart arrays of tubes and a single intermediate tube therebetween. Tubes in one array may have perforations or apertures to permit expansion of exhaust gases, while the other array may define at least one tuning tube. The tubes are disposed on the internal plates such that at at least one location thereon a straight line extending entirely across said internal plates will intersect only the one intermediate tube. The external shells are stamp formed to define a plurality of chambers which cooperate with the tubes in the internal plates. The chambers are separated from one another by a crease disposed to align with the intermediate tube. The crease is characterized by a single outwardly convex portion to engage the single bulb. As a result, the crease is not provided with recesses that conceivably could retain corrosive materials.

Abstract: A stamp formed exhaust muffler for mounting on a vehicle is provided. The muffler comprises a plurality of plates secured in juxtaposed relationship and stamp formed to define an array of tubes therebetween. At least one external shell is secured to the internal plates to define at least one chamber which communicates with the array of tubes. The external shell includes a conformal area which permits the muffler to conform to the shape of a structure on the vehicle. The conformal area may be an area of generally arcuate concavity when viewed from the exterior of the muffler or may define an internal corner on the muffler. Thus, a plane or line connecting two locations on the conformal area of the external shell will pass through the interference zone of a structure on the vehicle.

Abstract: A process and an apparatus for forming an air gap pipe are provided. Inner and outer pipes are bent or deformed into comparable configurations such that the inner pipe can be mounted within the outer pipe. The outer pipe then is split longitudinally by a preprogrammed cutting apparatus. The cutting of the outer pipe terminates just short of the complete longitudinal length of the pipe to facilitate rematching later in the process. The cutter includes a follower to trace the actual configuration of the pipe and thereby to offset differences from one pipe to the next. An array of clamps are provided to align the outer pipe halves relative to one another and to facilitate the reattachment.

Abstract: A muffler is provided with a pair of internal plates stamp formed to define an array of tubes therebetween. An external shell, which may be stamp formed, surrounds and encloses at least selected portions of the internal plates. The array of tubes stamp formed in the internal plates includes at least two tuning tubes. One tuning tube terminates at a tuning aperture in one of the two internal plates, while the other tuning tube terminates at an aperture stamp formed in the other of the two internal plates. Thus, one tuning tube will communicate with a low frequency resonating chamber on one side of the pair of internal plates, while the other tuning tube will communicate with a low frequency resonating chamber on the opposite side of the assembled internal plates.

Abstract: An exhaust muffler is provided. The muffler may be formed from a pair of internal plates that are secured in registration with one another and are formed to define an array of tubes through which the exhaust gages may travel. Selected portions of the tubes in the internal plates may be formed to include perforations. The muffler may further include at least one external shell formed to define at least one chamber which may at least partly surround the perforations in the internal plates. At least one inlet or outlet may lie on the seam between the formed plate members. However, at least one inlet or outlet may also be provided through a portion of the muffler spaced from the seams. The inlet and/or the outlet may be angularly aligned to the longitudinal axis of the muffler and may further be angularly aligned to one another.

Abstract: A muffler is provided including a pair of internal plates formed to define an array of tubes. At least one external shell is formed to define at least one chamber which will surround and enclose a selected portion of the array of tubes. Selected portions of certain tubes will be formed to include perforations. Portions of certain tubes will further undergo cross-sectional changes to control the flow of exhaust gases through the muffler. Certain channels between adjacent chambers of the external shell will be disposed to extend substantially continuously from peripheral portions of the adjacent chambers formed in the external shell. In certain embodiments, a controlled communication is provided between a low frequency resonating chamber and an adjacent expansion chamber. In other embodiments, additional formed layers are provided to enhance either heat or noise insulation.

Abstract: A precision bending apparatus is provided for precisely bending tubes. The precision bending apparatus includes a preprogrammed bender for placing a selected sequence of bends in the tube. The apparatus further includes a position sensing means for sensing the precise position of locations on the bent portion of the tube. A control means is in communication with both the position sensing means and the bender, and is operative to alter the program of the bender based on data sensed by the position sensing means.

Abstract: A process and an apparatus for forming an air gap pipe are provided. Inner and outer pipes are bent or deformed into comparable configurations such that the inner pipe can be mounted within the outer pipe. The outer pipe then is split longitudinally by a preprogrammed cutting apparatus. The cutting of the outer pipe terminates just short of the complete longitudinal length of the pipe to facilitate rematching later in the process. The cutter includes a follower to trace the actual configuration of the pipe and thereby to offset differences from one pipe to the next. An array of clamps are provided to align the outer pipe halves relative to one another and to facilitate the reattachment.

Abstract: A process and an apparatus for forming an air gap pipe are provided. Inner and outer pipes are bent or deformed into comparable configurations such that the inner pipe can be mounted within the outer pipe. The outer pipe then is split longitudinally by a preprogrammed cutting apparatus. The cutting of the outer pipe terminates just short of the complete longitudinal length of the pipe to facilitate rematching later in the process. The cutter includes a follower to trace the actual configuration of the pipe and thereby to offset differences from one pipe to the next. An array of clamps are provided to align the outer pipe halves relative to one another and to facilitate the reattachment.

Abstract: An air gap pipe and a method for forming the same are provided. The air gap pipe includes a non-linear outer pipe and an inner pipe of identical configuration disposed concentrically within the outer pipe. The inner pipe is supported by resilient dimples in the outer pipe. The outer pipe is placed in a condition for receiving the inner pipe by longitudinally cutting the outer pipe in half with a pre-programmed plasma arc or laser cutting apparatus. The two halves of the outer pipe are secured together to provide vents, if necessary, for selective dissipation of heat.

Abstract: An air gap pipe and a method for forming the same are provided. The air gap pipe includes a non-linear outer pipe and an inner pipe of identical configuration disposed concentrically within the outer pipe. The inner pipe is supported by resilient dimples in the outer pipe. The outer pipe is placed in a condition for receiving the inner pipe by longitudinally cutting the outer pipe in half with a pre-programmed plasma arc or laser cutting apparatus. The two halves of the outer pipe are secured together to provide vents, if necessary, for selective dissipation of heat.

Abstract: A hybrid exhaust manifold is provided for use with a vehicular engine. The manifold includes an inlet flange formed from a metal plate to be mounted against the engine cylinder head. The inlet flange includes exhaust ports which align with the exhaust ports of the engine cylinder head. Inner and outer stamped sheet metal shells are provided to mate with one another for forming an enclosed exhaust chamber. The inner shell includes inlet apertures which align respectively with the exhaust ports of the inlet flange. The outer shell includes an outlet aperture. An outlet tube is affixed to the outlet aperture of the outer shell, and an outlet flange is affixed to the end of the outlet tube opposite the outer shell to facilitate connection of the outlet tube to the exhaust pipe. The subject hybrid exhaust manifold can be adapted to fit within a very small space envelope in the engine compartment.

Abstract: An air gap pipe and a method for forming the same are provided. This air gap pipe includes a non-linear outer pipe and an inner pipe of identical configuration disposed concentrically within the outer pipe. The inner pipe is supported by resilient dimples in the outer pipe. The outer pipe is placed in a condition for receiving the inner pipe by longitudinally cutting the outer pipe in half with a pre-programmed plasma arc or laser cutting apparatus. The two halves of the outer pipe are secured together to provide vents, if necessary, for selective dissipation of heat.

Abstract: Various universal muffler assemblies are disclosed which allow one or more muffler nipples to be secured to a selected muffler body at the time of installation.

Abstract: A technique for threadedly securing muffler nipples to a muffler body is disclosed. The muffler nipples are provided with a threaded portion which is adapted to be inserted into a bushing attached to the muffler body, threadedly secured thereto, and tightened with a predetermined torque designed to prevent the nipples from unthreading or loosening within the muffler body.