Acoustic muffler

Claim 2

An acoustic muffler for attenuating sound in motor vehicle exhaust gases comprising a housing having inlet and outlet means for gas flow, means for providing a chamber having an annular outer wall defining a shape of the chamber, a cartridge composed of a soft core of unbonded fibrous glass sound absorbent material and including an annular fibrous hard outer shell of bonded fibrous glass sound absorbent material preformed to and retaining said chamber shape, gas flow means in said cartridge for allowing gas to flow through said soft core, said hard outer shell confining and holding said soft core so that said cartridge is adapted to be handled as a one piece component in assembly of the muffler, said cartridge having a slip fit inside said chamber with said outer shell engaging said annular wall, and gas passage means for the flow of exhaust gas between the inlet and outlet means and providing for acoustic communication of the exhaust gas with the gas flow means for the core of said cartridge.

Claim 3

A muffler as set forth in claim 1 wherein said gas flow means comprises at least one hole extending through said core and a preforated sleeve of high temperature withstanding material extending along a length of the hole.

Claim 4

A muffler as set forth in claim 2 wherein said gas passage means includes a gas tube extending through said perforated sleeve and having openings into the perforated sleeve to provide said acoustic communication.

Claim 5

A muffler as set forth in claim 1 wherein the fibers of said fibrous glass are about 7 microns in diameter and said fibrous glass core is unbonded and unlubricated.

Claim 6

An acoustic component for a motor vehicle exhaust muffler provided with inlet and outlet means for gas flow comprising a cartridge composed of a soft core of unbonded sound absorbent fibrous glass and a hard, molded annular outer shell of fibrous glass surrounding and containing said core to confine and hold said core and preformed to a predetermined shape whereby said fibrous glass cartridge may be handled efficiently in production and assembly of a muffler and inserted by slip fit into a muffler housing, and gas flow means through said core for allowing gas to flow from said inlet to said outlet means.

Claim 7

An acoustic component for a motor vehicle exhaust muffler provided with inlet and outlet means for gas flow comprising a cartridge composed of a soft core of unbonded sound absorbent fibrous glass and a hard, molded annular outer shell of fibrous glass surrounding and containing said core to confine and hold said core and preformed to a predetermined shape whereby said fibrous glass cartridge may be handled efficiently in production and assembly of a muffler and inserted by slip fit into a muffler housing, and gas flow means through said core for allowing gas to flow from said inlet to said outlet means.

Claim 8

A component as set forth in claim 5 wherein said gas flow means comprises at least one hole extending longitudinally through said core and a preforated sleeve of high temperature withstanding material extending along a length of the hole.

Claim 9

An acoustic muffler for attenuating sound in motor vehicle exhaust gases comprising a tubular housing having inlet and outlet means for gas flow, said housing having a transverse chamber and at least one longitudinally extending gas flow tube passing through the chamber, a cartridge sized and shaped to fill said chamber and having an opening through said cartridge for passage of said gas flow tube, said cartridge being composed entirely of non-metallic fibrous sound absorbent material and having a soft core of said fibrous material in unbonded condition and a hard outer tubular shell of bonded fibrous material conforming in shape and and size to said tubular housing, whereby said cartridge is adapted to slip fit as a unit into said tubular housing and into said chamber with an outside of the outer tubular shell substantially in contact with an inside of said tubular housing, said hard outer tubular shell confining and holding said soft core fibrous material so that said cartridge may be handled efficiently in production and during assembly of said muffler.

Claim 10

An acoustic muffler for attenuating sound in motor vehicle exhaust gases comprising a tubular housing having inlet and outlet means for gas flow, said housing having a transverse chamber and at least one longitudinally extending gas flow tube passing through the chamber, a cartridge sized and shaped to fill said chamber and having an opening through said cartridge for passage of said gas flow tube, said cartridge being composed entirely of non-metallic fibrous sound absorbent material and having a soft core of said fibrous material in unbonded condition and a hard outer tubular shell of bonded fibrous material conforming in shape and and size to said tubular housing, whereby said cartridge is adapted to slip fit as a unit into said tubular housing and into said chamber with an outside of the outer tubular shell substantially in contact with an inside of said tubular housing, said hard outer tubular shell confining and holding said soft core fibrous material so that said cartridge may be handled efficiently in production and during assembly of said muffler.

Claim 11

A muffler as set forth in claim 7 including a perforated sleeve of high temperature withstanding material extending along a length of said opening in said cartridge, said gas flow tube extending through said sleeve.