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US4069768A Expired / Lapsed US ⏱️ 0.0 years remaining

Device for controlling a propagation direction of noise

Assignee: Bridgestone Corp
•
Filing: 1976-05-14
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Granted: 1978-01-24
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Expires: 1996-05-14
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Abstract

Abstract A device for controlling a propagation direction of noise which is preferably associated with a sound insulating wall to significantly improve its sound reducing effect of alleviating noise emitted from a noise source such as a railroad, highway and the like on which an electric car and automobiles run. The device comprises a hollow structural body composed of a plurality of elongate hollow passages superimposed one upon the other and spaced apart from each other. The passages are arranged in a propagation direction of noise emitted from the noise source and serve to refract and lag in phase the noise passed therethrough, thereby producing a sound reducing region located intermediate between a direct propagation sound and the refraction propagation sound.

Inventors

  • 👤 Masayasu Matsumoto
  • 👤 Kazuyoshi Iida
  • 👤 Yoshikazu Kondo
  • 👤 Keiichiro Mizuno
  • 👤 Sadao Nomoto
  • 👤 Noriaki Murayama
  • 👤 Kei Watanabe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 10:07
CPC Classifications
G; G10; G10K; G10K11/00; G10K11/16; G10K11/175; E; E01; E01F; E01F8/00; E01F8/0005; E01F8/0041

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 123 words
A device for controlling a propagation direction of noise, comprising a hollow structural body composed of a plurality of elongate hollow passages superimposed one upon the other and spaced apart from each other, said passages being arranged in a propagation direction of noise emitted from a noise source, and adjacent passages located at least on a line perpendicular to said propagation direction and being different in length from each other, said noise emitted from said noise source passing through said adjacent passages of different length and refracted by all of said passages and lagged in phase with respect to direct propagation sound emitted from said noise source and passed over the upper edge of said hollow structural body to produce a sound region.
Claim 2
Independent Claim 123 words
A device for controlling a propagation direction of noise, comprising a hollow structural body composed of a plurality of elongate hollow passages superimposed one upon the other and spaced apart from each other, said passages being arranged in a propagation direction of noise emitted from a noise source, and adjacent passages located at least on a line perpendicular to said propagation direction and being different in length from each other, said noise emitted from said noise source passing through said adjacent passages of different length and refracted by all of said passages and lagged in phase with respect to direct propagation sound emitted from said noise source and passed over the upper edge of said hollow structural body to produce a sound region.
Claim 3
Dependent Claim 32 words
A device for controlling a propagation direction of noise as claimed in claim 1, wherein said elongate hollow passages are inclined from a substrate by an angle α of 30° to 80°.
Claim 4
Dependent Claim 70 words
A device for controlling a propagation direction of noise as claimed in claim 1, wherein each of said passages is square in section and has a height H measured on a line perpendicular to the bottom surface of said passage, H being shorter than 1/2 times the wave length λ of the maximum frequency f in a frequency range to be controlled of the noise emitted from the noise source.
Claim 5
Dependent Claim 68 words
A device for controlling a propagation direction of noise as claimed in claim 1, wherein the maximum length L of said adjacent elongate hollow passages which are measured along said passages is defined to a length which is longer than 1/2 times the wave length λ of the minimum frequency f in a frequency range of that noise emitted from the noise source which is to be controlled.
Claim 6
Dependent Claim 46 words
A device for a propagation direction of noise as claimed in claim 1, wherein said plurality of elongate hollow passages are inclined with respect to the substrate, each cross sectional area of said passages being enlarged from its sound inlet side toward its sound outlet side.
Claim 7
Dependent Claim 99 words
A device for controlling a propagation direction of noise as claimed in claim 1, wherein the height h of the device is at least equal to either one of two lines which is lower than the other, said lines consisting of a line connecting a contact portion of a rail with a wheel of an electric car to the front upper edge of a sound insulating wall and a line connecting a midpoint between a road bed and the lower edge of a side plate of said electric car to the front upper edge of said sound insulating wall.
Claim 8
Dependent Claim 71 words
A device for controlling a propagation direction of noise as claimed in claim 1, wherein said device is secured to the lower peripheral edge of a side plate of an electric car such that at least the bottom portion of the device is projected below a line connecting a contact portion of a rail with a wheel of said electric car to the front upper edge of a sound insulating wall.
Claim 9
Dependent Claim 48 words
A device for controlling a propagation direction of noise as claimed in claim 1, wherein said plurality of elongate hollow passages are formed by a number of plates superimposed one upon the other and spaced apart from each other by means of partition walls sandwiched between adjacent plates.
Claim 10
Dependent Claim 20 words
A device for controlling a propagation direction of noise as claimed in claim 10, wherein said plates are ridge-shaped plates.
Claim 11
Dependent Claim 20 words
A device for controlling a propagation direction of noise as claimed in claim 8, wherein said plates are groove-shaped plates.
Claim 12
Dependent Claim 32 words
A device for controlling a propagation direction of noise as claimed in claim 1, wherein said plurality of elongate hollow passages are formed by a number of honeycomb-shaped square elongate hollow passages.
Claim 13
Dependent Claim 75 words
A device for controlling a propagation direction of noise as claimed in claim 1 and further comprising a fixture for supporting said device on a substrate along a railroad, said fixture comprising a supporting member projected in a direction perpendicular to said substrate and secured thereto, said supporting member being provided at its upper portion with a T-shaped fitting portion which is engageable with a groove provided on each lower side surface of said device.

References Cited (Backward Citations)

US2726830A Cited
US3177970A Cited
US3111191A Cited
US3212453A Cited
DE2158702A1 Cited
US3772993A Cited
US3812931A Cited
US3830335A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-01-23 1981-07-25 1982-01-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-01-23 1985-07-25 1986-01-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-01-23 1989-07-25 1990-01-24 $7700.00 Window Closed / Lapsed

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