Muffler structures
AssigneeDonley, Miller & Nowikas
InventorWalter M. Nowikas
Life of this patent
Estimating the term…
Abstract
An enclosure for isolating noise sources composed of four walls and a ceiling, in which some or all of the sides and top consist of a muffler barrier including one or more air paths transverse to the principal direction of sound transmission through the structure. Various types of component muffler barriers are illustrated which include double leaf structures lined with sound absorbing material where the two leaves are disposed in spaced apart relation and include oppositely disposed air intakes and air exhausts to provide the intervening air paths. In one embodiment, components comprise corrugated panels of sound absorbing material disposed in face-to-face relation to provide multiple air channels.
Claims4
An enclosure for providing acoustic isolation from sounds within or without said enclosure formed from a plurality of muffler barriers joined together in contiguous air-tight relation, each said muffler barrier constructed to enclose a principal passage for the free flow of air therethrough in a direction substantially transverse to the principal direction of sound transmission without substantial reduction in the composite sound transmission loss through said enclosure,
- at least one said muffler barrier comprising:
- a pair of substantially parallel leaves disposed in spaced apart relation, each comprising a rigid backing,
- the inwardly directed face of each of said leaves being lined with a layer of sound absorbing material impressed with a series of corrugations of saw-tooth cross-section longitudinally extended in a direction substantially parallel to a major edge of the said leaf, said leaves bonded together with the said corrugations in face-to-face relation at their apexes providing between them a series of longitudinal air channels comprising said principal air flow passage,
- air intake and exhaust openings respectively disposed at corresponding opposite positions near the ends of each of said leaves in transverse relationship to said longitudinal air channels, whereby the air intake is at one end of one said leaf and the air exhaust is at the other end of the other said leaf, with the longitudinal air channels extending between said openings.
An enclosure for providing acoustic isolation from sounds within or without said enclosure formed from a plurality of muffler barriers joined together in contiguous air-tight relation, each said muffler barrier constructed to enclose a passage for the free flow of air therethrough in a direction substantially transverse to the principal direction of sound transmission without substantial reduction in the composite sound transmission loss through said enclosure,
- at least one said muffler barrier comprising:
- a pair of substantially parallel rigid leaves disposed in spaced apart relation and forming between them at least one closed internal chamber, the opposite internal leaves of said chamber being respectively lined with layers comprising a series of panels of laterally corrugated sound absorbing material interposed transversely between said leaves, said panels being disposed in substantially parallel noncontiguous relation forming between them channels comprising said passage for the free flow of air, at least one air intake opening on one said leaf leading into one end of said channels, and at least one corresponding air exhaust opening in the other said leaf leading out from the other end of said channels, said air flow channels thereby comprising a series of elongated zig-zag paths running at least part of the length of said walls between said intake and exhaust openings.
A muffler barrier comprising in combination a pair of rigid leaves each lined with a layer of sound absorbing material, each said layer of sound absorbing material impressed with a series of corrugations of saw-tooth cross-section longitudinally extended substantially parallel to a major edge of said leaf, said leaves bonded together with the said corrugations in face-to-face relation at their apexes providing between them a series of longitudinal air channels,
- intake and exhaust openings respectively disposed at correspoinding opposite positions near the opposite ends of each of said leaves in transverse relationship to said longitudinal air channels, whereby the air intake is at one end of one said leaf and the air exhaust is at the other end of the other said leaf with the longitudinal air channels extending between said openings.
An enclosure for providing acoustic isolation from sounds within or without said enclosure formed from a plurality of muffler barriers joined together in contiguous air-tight relation, said muffler barriers constructed to enclose a principal passage for the free flow of air therethrough in a direction substantially transverse to the principal direction of sound transmission without substantial reduction in the composite sound transmission loss through said enclosure,
- at least one said muffler barrier comprising:
- a pair of substantially parallel leaves spaced apart by a series of symmetrically spaced longitudinally extending isolator studs forming between them a series of partially closed longitudinal chambers wherein said principal air flow passage comprises a plurality of channels extending in the direction of the major dimension of said leaves, air intake openings corresponding to each of said channels at one end of one said leaf and air exhaust openings corresponding to each of said channels at the other end of said other leaf,
- each of said leaves comprising a metal backing sheet, a first sound absorbing layer comprising a layer of glass fiber bonded to the inner surface of one said backing sheet, a foam laminate formed from layers of plastic foam bonded on opposite sides of a leaded transmission loss separator, a second sound absorbing layer comprising said foam laminate bonded to the inner surface of the other said backing sheet, wherein said air flow channels extend from said intake openings to said exhaust openings passing between said first and second sound absorbing layers.
Dependencies are inferred from the claim text.