Longitudinally reinforced flexible duct

Claim 2

A flexible insulated duct comprising a wire helix secured at each end to a longitudinally reinforced connector member, wrapped with glass fibrous insulating material and encased in a flexible fluid-impermeable sleeve, said longitudinal reinforcement consisting of flexible cordlike tension means affixed to said connector members to enhance the axial tensile strength of the duct while maintaining its bendability and twistability.

Claim 3

The flexible insulated duct of claim 1 wherein said flexible cordlike tension means comprises at least a pair of metal wires disposed at spaced locations about the periphery of said wire helix so that said metal wires are substantially parallel to the axis of the duct.

Claim 4

The flexible insulated duct of claim 2 wherein said wires are composed of galvanized steel wire having a uniform zinc coating of 0.3 ounce per square foot of surface area coated.

Claim 5

The flexible insulated duct of claim 1 wherein said flexible cordlike tension means comprises at least a pair of fiber glass cords spaced approximately 180* apart so that said fiber glass cords are substantially parallel to the axis of the duct.

Claim 6

A flexible insulated duct comprising a continuous wire helix, a connector member secured to each end of said wire helix, longitudinal reinforcement consisting of flexible cordlike tension means affixed to said connector members to enhance the axial tensile strength of the duct, a coherent, strand-individual fiber insulating material wrapped about said helix, means for affixing the insulating material to said wire helix and a flexible sleeve disposed about said insulating material and said helix.

Claim 7

A flexible insulated duct comprising a continuous wire helix, a connector member secured to each end of said wire helix, longitudinal reinforcement consisting of flexible cordlike tension means affixed to said connector members to enhance the axial tensile strength of the duct, a coherent, strand-individual fiber insulating material wrapped about said helix, means for affixing the insulating material to said wire helix and a flexible sleeve disposed about said insulating material and said helix.

Claim 8

The flexible insulated duct of claim 5 wherein said insulating material extends past said wire helix to essentially completely cover the outer surface of one of said connector members and to partially cover the outer surface of the other of said connector members.

Claim 9

The flexible insulated duct of claim 6 wherein the strand-individual fiber composite insulating material is fabricated from fiber glass and the means for affixing the wire helix to the insulating material comprises a nonflammable adhesive.

Claim 10

The flexible insulated duct of claim 7 wherein said flexible cordlike tension means comprises at least a pair of metal wires spaced approximately 180* apart so that said metal wires are substantially parallel to the axis of the duct.

Claim 11

The flexible insulated duct of claim 7 wherein said flexible cordlike tension means comprises at least a pair of fiber glass cords spaced approximately 180* apart so that said fiber glass cords are substantially parallel to the axis of the duct.

Claim 12

A flexible insulated duct comprising a continuous wire helix, a connector member secured to each end of said wire helix, longitudinal reinforcement consisting of flexible cordlike tension means affixed to said connector members to enhance the axial tensile strength of the duct, a coherent, strand-individual fiber, glass fibrous insulating material wrapped about said helix and extending past said helix to essentially completely cover the outer surface of one of said connector members and to partially cover the outer surface of the other of said connector members, adhesive means for affixing the helix to adjacent strands of the insulating material and for affixing the insulating material to the connector members to add to the strength and integrity of the duct, and a flexible, fluid-impermeable sleeve disposed about said insulating material, said helix and said connector members.

Claim 13

A flexible insulated duct comprising a continuous wire helix, a connector member secured to each end of said wire helix, longitudinal reinforcement consisting of flexible cordlike tension means affixed to said connector members to enhance the axial tensile strength of the duct, a coherent, strand-individual fiber, glass fibrous insulating material wrapped about said helix and extending past said helix to essentially completely cover the outer surface of one of said connector members and to partially cover the outer surface of the other of said connector members, adhesive means for affixing the helix to adjacent strands of the insulating material and for affixing the insulating material to the connector members to add to the strength and integrity of the duct, and a flexible, fluid-impermeable sleeve disposed about said insulating material, said helix and said connector members.