Sound attenuator
Patent 4421202 Issued on December 20, 1983. Estimated Expiration Date: 
March 20, 2001. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
March 20, 2001. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesInventorAssigneeApplicationNo. 06/245903 filed on 03/20/1981US Classes:181/252, With sound absorbing material138/130, Oppositely wound138/132, Embedded138/149, With intermediate insulation layer138/174, With embedded element181/225, With fan to assist fluid flow181/243, With repair, replacement, or quick disassembly181/244Corrosion preventionExaminersPrimary: Fuller, Benjamin R.Attorney, Agent or FirmInternational ClassesF24F 13/00 (20060101)F16L 55/02 (20060101) F16L 55/027 (20060101) F24F 13/24 (20060101) AbstractA sound attenuator comprising concentric inner and outer tubular members having sound absorbing material positioned therebetween. The inner tubular member comprises a lattice of reinforcing strand material coated with solidified resin wherein the strand material is formed in opposed generally helical patterns to provide the lattice. The attenuator is suitable for use in reducing noise produced by axial flow fans used in industrial environs such as mines and factories.Field of SearchSound absorbing ventilating duct or curb (e.g., a/c, heat, air flow type)With fan to assist fluid flow With solid particle separator (e.g., spark arrestor, vacuum cleaner, etc.) Pipe-muffler (e.g., tail pipe type) Corrosion prevention Internally coated parts Nonmetallic Straight-through passage Continuous conduit With sound absorbing material With sound absorbing material Pervious material interposed in flow path Helical | |
