Patent ID: 7360499

Claim:
A power efficient acoustical Helmholtz type marine navigational foghorn assembly commonly installed on remote off-shore unmanned well sites and buoys as a navigational warning aid for marine hazards, in conformance with regulations established by the United States Coast Guard the foghorn comprising: a) a base plate having means for securing said foghorn vertically to said offshore well sites and buoys; b) a tubular resonating member having a constant diameter throat and at least one sound pressure wave outlet orifice located approximately mid-way there along, said resonating member attached perpendicular to said base plate thereby closing one end of said tubular resonating member, said orifice location and its size and shape, along with diameter, length and wall thickness of said resonating member determining resonance of said Helmholtz type foghorn; c) a tubular collar serving as a bidirectional acoustic wave guide surrounding said tubular resonating member in a standoff relationship surrounding each said sound pressure wave outlet orifice, spacing between said resonating member and said tubular collar contributing to resonance and pitch of said foghorn; d) a manifold having a flange portion and a plurality of threaded ports attached to an end of said tubular resonating member located opposite said base plate, each of said threaded ports in sound pressure wave communication with said constant diameter throat of said tubular resonating member; e) a plurality of electrical acoustic transducer sound emitters attached via said threaded ports located in said manifold; f) a detachable watertight cover fully enclosing said acoustic transducer emitters having means for securing said cover to said flange portion and a means for attaching and fully supporting a second said Helmholtz type marine navigational foghorn assembly to an external upper surface of said cover.