Heat and sound insulation device

Claim 1

A heat and sound insulation device adapted for use as a muffler through which may be flowed exhaust gases from an internal combustion engine, which comprises: (a) an exhaust passage having peripheral walls, an inlet thereto and an outlet therefrom; (b) a plurality of partitions in said passage to provide a plurality of compartments therealong; (c) means for flowing exhaust gases through said compartments and out of said outlet; and (d) said peripheral walls being lined with heat and sound insulation material made by mixing enlongate glass fibers with ceramic fibers composed of 45% kaolin and 52% silicic acid to form a mass in which the ratio of ceramic fibers to glass fibers is in the range of 35 to 70 weight percent, impregnating said mass with an inorganic binder of water glass and thereafter pressing said mass in a die to a density of at least 200 Kg/m 3 to a predetermined shape.

Claim 4

A device as claimed in claims 1 or 2, wherein said partitions are mounted with their outer periphery engaging in recesses defined in said heat and sound insulation material.

Claim 5

A device as claimed in claims 1 or 2, wherein said die pressed heat and sound insulating material is formed in two pieces to form said exhaust passage, and said partitions are formed into a unit of plural partitions, connected by a communication pipe and an exhaust pipe and said device is assembled by positioning said unit of partitions within said two pieces of heat and sound insulation material and joining the assembly together.

Claim 11

A device as claimed in claims 1 or 2, wherein said heat and sound insulation material has a tubular form and is covered with two joined halves of an outer tubular body of the heat and sound insulation material.