Ventilation duct line assembly and apparatus

Patent metadata

Field	Value
Publication number	US-2020200433-A1
Application number	US-201816645841-A
Country	US
Kind code	A1
Filing date	Jun 28, 2018
Priority date	Oct 12, 2017
Publication date	Jun 25, 2020
Grant date	—

Abstract

A first ventilation duct line has a first portion having a first sectional area, a second portion having a second sectional area larger than the first sectional area, and a third portion having an inclined inner face connecting the first portion and the second portion to each other. Further, there is a second ventilation duct line having an opening portion positioned on an inner side of the first portion of the first ventilation duct line.

First claim

1 . A ventilation duct line assembly comprising:
a first ventilation duct line through which sound can pass between at least two openings, and the first ventilation duct having a first portion having a first sectional area, a second portion having a second sectional area larger than the first sectional area, and a third portion having an inclined inner face connecting the first portion and the second portion to each other; and a second ventilation duct line that has an opening portion positioned on an inner side of the first portion of the first ventilation duct line so that sound received from the opening portion is reflected inside the second ventilation duct line and then emitted from the opening portion.

2 . The ventilation duct line assembly according to claim 1 , wherein the opening portion of the second ventilation duct line is shaped to be a rectangle or an ellipse, and a longitudinal direction of the opening portion intersects with a direction in which the first ventilation duct line extends.

3 . The ventilation duct line assembly according claim 1 , wherein the second ventilation duct line is disposed at an inner side of the first ventilation duct line.

4 . The ventilation duct line assembly according to claim 3 , wherein at least a portion of an outer face of the second ventilation duct line is bonded to a portion of an inner face of the first ventilation duct line.

5 . The ventilation duct line assembly according to claim 4 , wherein a distance between an opposed face of the second ventilation duct line on an opposite side to the bonding face of the second ventilation duct line and an inner face of the first ventilation duct line is shorter than a longitudinal-direction length of the bonding face of the second ventilation duct line.

6 . The ventilation duct line assembly according to claim 4 , wherein:
the first portion of the first ventilation duct line has a width in a direction intersecting with a direction in which the first ventilation duct line extends; and the second ventilation duct line is provided to extend from one end of the first portion to the other end of the first portion in the width direction, and in the opening portion of the second ventilation duct line, a longitudinal-direction length of the opening portion is a length which is 90% or more of a width-direction distance between the one end of the first portion and the other end of the first portion.

7 . The ventilation duct line assembly according to claim 1 , wherein:
a box having an opening portion is placed at an inner side of the first ventilation duct line; and the second ventilation duct line is formed by an internal space of the box.

8 . The ventilation duct line assembly according to claim 7 , wherein the box is formed into a shape of a rectangular parallelepiped.

9 . The ventilation duct line assembly according to claim 8 , wherein the box having the shape of the rectangular parallelepiped has three pairs of outer faces which are opposed to each other; a first face of the box, which is one of one pair of the outer faces each having a largest area, of the three pairs of the outer faces, has the opening portion; and a second face of the box opposed to the first face of the box is bonded to the inner face of the first ventilation duct line.

10 . The ventilation duct line assembly according to claim 1 , wherein:
a portion of the inner face of the first ventilation duct line is formed to be opposed to an air intake port of the first ventilation duct line; and an air outtake port side of the first ventilation duct line continuous to the portion of the inner face of the first ventilation duct line opposed to the air intake port is formed to be opposed to the opening portion of the second ventilation duct line.

11 . The ventilation duct line assembly according to claim 1 , wherein an air outtake port of the first ventilation duct line is formed to face down in a vertical direction.

12 . The ventilation duct line assembly according to claim 1 , wherein an area of an air outtake port belonging to the first ventilation duct line is larger than the sectional area of the first portion.

13 . The ventilation duct line assembly according to claim 1 , wherein the first portion of the first ventilation duct line is formed so that the first sectional area in the sectional area of the first ventilation duct line is smallest.

14 . A ventilation duct line assembly comprising:
a first ventilation duct line through which sound can pass between at least two openings, the first ventilation duct line having a first portion having a first sectional area, an outtake port that is one of the at least two openings and serves for discharging air, and whose area is larger than the first sectional area, and a second portion having an inclined inner face connecting the first portion and the outtake port to each other; and a second ventilation duct line that has an opening portion positioned on an inner side of the first portion of the first ventilation duct line so that sound received from the opening portion is reflected inside the second ventilation duct line and then emitted from the opening portion.

15 . The ventilation duct line assembly according to claim 1 , wherein:
the second ventilation duct line has a resonance frequency fr [Hz]; and at a frequency fma [Hz] highest among frequencies at each of which transmission loss is minimum about a transmission loss spectrum of the first ventilation duct line and that are lower than the resonance frequency fr, the second ventilation duct line satisfies the following expression (2)
0≤ La 1≤λfma/4   (2)

where La1 designates a distance between the opening portion of the second ventilation duct line and a position of the first ventilation duct line at which sound pressure is maximum and that is nearest to the opening portion with respect to the same direction as a flowing direction of the sound at the frequency fma, and λfma designates a wavelength at the frequency fma.

16 . The ventilation duct line assembly according to claim 1 , wherein:
the second ventilation duct line has a resonance frequency fr [Hz]; and at a frequency fmb [Hz] lowest among frequencies at each of which transmission loss is minimum about a transmission loss spectrum of the first ventilation duct line and that are higher than the resonance frequency fr, the second ventilation duct line satisfies the following expression (4)
λfmb/4≤ La 2≤λfmb/2   (4)

where La2 designates a distance between the opening portion of the second ventilation duct line and a position of the first ventilation duct line at which sound pressure is maximum and that is nearest to the opening portion with respect to the same direction as a flowing direction of the sound at the frequency fmb, and ,fmb designates a wavelength at the frequency fmb.

17 . The ventilation duct line assembly according to claim 1 , wherein a porous material is placed on an inner face of the second portion and/or the third portion.

18 . An apparatus comprising:
a sound source; and a fourth partial ventilation duct line through which sound from the sound source can be passed; wherein: the fourth partial ventilation duct line is connected to the ventilation duct line assembly according to claim 1 .

Assignees

• Fuji Xerox Co Ltd
• Fujifilm Corp

Inventors

• Kumeta Koichi
• Kokubu Fuyuki
• Mitourida Shinya
• Umenai Koh
• Yamazoe Shogo
• Hakuta Shinya
• Ohtsu Akihiko

Classifications

• G10K11/161 Primary

  in systems with fluid flow (G10K11/162 takes precedence; gas flow silencers or exhaust apparatus for machines or engines in general or for internal combustion engine F01N, noise absorbers in pipes or pipe systems F16L55/02; noise absorption in air conditioning and ventilation F24F13/24; silencing exhaust or propulsion jets in aircraft B64D33/06) · CPC title

• G10K11/172

  using resonance effects · CPC title

• F24F13/24 Primary

  Means for preventing or suppressing noise · CPC title

• F24F2013/245

  using resonance · CPC title

• B41J29/10

  Sound-deadening devices embodied in machines · CPC title