Exhaust system assemblies employing wire bushings for thermal compensation
AssigneeGeneral Motors Corporation
InventorDouglas M. Kerchner
Life of this patent
Estimating the term…
Abstract
Exhaust system assemblies employ wire bushings for thermal compensation to minimize noise due to “stick-slip” while the system cools. In a preferred embodiment, the wire bushings are formed of at least one strand of wire coiled about male end portions of pipe sections used in the system, each of which male end portions are inserted into a female end portion and held therein by an interference fit. The strand of wire is spot welded at spaced locations to the male end portions to provide bearing surfaces between the spot welds that move slightly as the exhaust system heats and cools to relieve thermal stress in small, substantially inaudible increments.
Claims10
A muffler for connecting with an exhaust pipe of an internal combustion engine, the muffler including a housing enclosing a space with a sound attenuating system therein, the muffler assembly comprising:
- an array of baffle plates within the housing and first and second end cap plates closing the housing, the plates having first rates of thermal expansion and being spaced from one another to define chambers within the housing;
- pipes extending through holes in the plates, wherein the holes are defined by axially extending surfaces, the pipes interconnecting the chambers and having second rates of thermal expansion different from the first rates, and
- wire bushings between at least one of the pipes and the holes in the plates to compensate for the different rates of thermal expansion between the pipes and plates.
A muffler for connecting with an exhaust pipe of an internal combustion engine, the muffler having a housing enclosing a space with a sound attenuating system therein, the muffler comprising:
- first and second end cap plates on the housing, the end cap plates each having a hole therethrough defined by an axially extending interior surface;
- inlet and outlet pipes having axially extending exterior surfaces on ends passing through the holes in the end cap plates of the housing with the exterior surfaces of the pipes being adjacent to the axially extending interior surfaces defining the holes;
- baffle plates within the housing, the baffle plates each having at least one hole therethrough defined by an axially extending surface;
- interior pipes with axially extending exterior surfaces passing through the holes through the baffle plates with the exterior surfaces of the pipes being adjacent to the axially extending interior surfaces defining the holes, and
- wire strand bushings between the interior surfaces of the holes and the exterior surfaces of the pipes to compensate for unequal thermal expansion of the plates and pipes.
Dependencies are inferred from the claim text.