U.S. patent number RE32,554 [Application Number 05/849,086] was granted by the patent office on 1987-12-08 for vent structure.
This patent grant is currently assigned to McDonnell Douglas Corporation. Invention is credited to Dennis E. Murphy.
United States Patent |
RE32,554 |
Murphy |
December 8, 1987 |
Vent structure
Abstract
A vent structure for equalizing the pressure on opposite sides
of a structure including a plenum formed at least in part by
movable vent panel and a hinged panel supporting wall having
overcenter biasing means, the plenum being pneumatically connected
to the side of the structure which will be the high pressure side
so that the condition requiring venting applies a differential
pressure across the hinged wall which tends to force it overcenter
against the overcenter biasing means thereby removing the normal
support from the vent panel which moves to open a vent passageway.
Spring-loaded flapper doors may be included in the plenum forming
structure to enable relief of pressure in the opposite
direction.
Inventors: |
Murphy; Dennis E. (Costa Mesa,
CA) |
Assignee: |
McDonnell Douglas Corporation
(Long Beach, CA)
|
Family
ID: |
27093752 |
Appl.
No.: |
05/849,086 |
Filed: |
November 7, 1977 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
641429 |
Dec 17, 1975 |
04033247 |
Jul 5, 1977 |
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Current U.S.
Class: |
244/118.5;
244/129.1; 454/73 |
Current CPC
Class: |
B64C
1/18 (20130101); B64D 13/02 (20130101); B64C
2001/009 (20130101) |
Current International
Class: |
B64C
1/00 (20060101); B64C 1/18 (20060101); B64D
13/00 (20060101); B64D 13/02 (20060101); B64D
013/04 () |
Field of
Search: |
;244/117R,118.1-118.6,119,129.1,129.4,129.5
;98/1.5,119,2.18,74,77,79,95 ;251/73 ;137/467,513.3,527 ;49/31,141
;52/1 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
"DC-10 Cabin Design Being Modified", Aviation Week and Space
Technology, Nov. 4, 1974, p. 27..
|
Primary Examiner: Barefoot; Galen
Attorney, Agent or Firm: Oblon, Fisher, Spivak, McClelland
& Maier
Claims
What is claimed is:
1. A vent for equalizing the pressure on opposite sides of a
structure comprising:
a movable vent panel which in a first position restricts the flow
from a first side of the structure to a second side thereof;
and
a plenum chamber pneumatically connected to the first side of the
structure, said chamber having at least one movable wall having
first and second sides, said first side of said movable wall being
in pneumatic connection with the first side of the structure and
said second side of said movable wall being in pneumatic connection
with the second side of the structure so that differential pressure
across the structure applies force to said wall, and bias means for
urging said movable wall into a first position, said movable wall
being operatively connected to said vent panel to maintain said
movable vent panel in said first position thereof when said movable
wall is in its first position whereby a predetermined differential
pressure is capable of overpowering said bias means to move said
movable wall to a position which allows said movable vent panel to
move to a second position wherein flow from the first side of the
structure to the second side is less restricted.
2. The vent defined in claim 1 including a second movable wall
hingedly connected to the said .[.first.]. .Iadd.at least one
.Iaddend.movable wall which also forms a portion of said plenum
chamber.
3. The vent defined in claim 2 including stop means which restrict
the relative motion of said .[.first.]. .Iadd.at least one movable
wall .Iaddend.and .Iadd.said .Iaddend.second movable wall members
to motion against said bias means when said .[.first.]. .Iadd.at
least one .Iaddend.movable wall is in its first position.
4. The vent defined in claim 3 wherein said bias means are
connected to urge said .[.first.]. .Iadd.at least one movable wall
.Iaddend.and .Iadd.said .Iaddend.second movable walls toward said
stop means until said .[.first.]. .Iadd.at least one
.Iaddend.movable wall is moved a predetermined distance from said
first position thereof, after which said bias means urge said
.[.first.]. .Iadd.at least one .Iaddend.movable wall away from said
first position thereof to said position of said .[.first.].
.Iadd.at least one .Iaddend.movable wall which allows said movable
vent panel to move to said second position.
5. The vent defined in claim 4 wherein said vent panel forms a
portion of said plenum chamber.
6. The vent defined in claim 5 including a vent housing having
opposite side walls, said vent panel and said second movable wall
being hingedly connected to said vent housing and said .[.first.].
.Iadd.at least one .Iaddend.movable wall being hingedly connected
to said vent panel so that said plenum chamber is bounded by at
least a portion of said vent housing including said opposite side
walls, said .[.first.]. .Iadd.at least one movable wall
.Iaddend.and .Iadd.said .Iaddend.second movable walls and at least
a portion of said vent panel.
7. The vent defined in claim 6 wherein said bias means includes a
spring connected between said vent structure and said .[.first.].
.Iadd.at least one .Iaddend.movable wall, said spring being
predeterminately preloaded when said .[.first.]. .Iadd.at least one
.Iaddend.movable wall is in said first position.
8. The vent defined in claim 6 wherein said .[.first.]. .Iadd.at
least one .Iaddend.movable wall is hingedly connected to said vent
panel at an intermediate location thereon, said vent panel
including a passageway for allowing restricted flow between the
opposite sides of the structure.
9. The vent defined in claim 6 wherein said vent panel forms a
portion of the interior wall adjacent the cabin floor of a
pressurizable aircraft, said vent panel including a dust cover
hingedly connected thereto to prevent flow between the floor and
said vent panel when said vent panel is in its first position.
10. The vent defined in claim 2 wherein at least one of said
movable walls includes pneumatic check valve means which enable
flow of air from the second side of the structure into said plenum
chamber when said second side of the structure is at a higher
.[.predetermine.]. .Iadd.predetermined .Iaddend.pressure than said
first.
11. The vent defined in claim 1 including linkage means hingedly
connected to said .[.first.]. .Iadd.at least one .Iaddend.movable
wall to form an overcenter linkage therewith.
12. The vent defined in claim 11 including stop means which
restrict relative motion between said .[.first.]. .Iadd.at least
one .Iaddend.movable wall and said linkage means to motion against
said bias means when said .[.first.]. .Iadd.at least one
.Iaddend.movable wall is in its first position.
13. The vent defined in claim 12 wherein said stop means are
mounted to said vent panel and include an abutment surface which
engages said .[.first.]. .Iadd.at least one .Iaddend.movable wall
when said .[.first.]. .Iadd.at least one .Iaddend.movable wall
.[.portion.]. is in its first position.
14. The vent defined in claim 12 wherein said stop means include a
plate connected to said .[.first.]. .Iadd.at least one
.Iaddend.movable wall which bears against said linkage means when
said .[.first.]. .Iadd.at least one .Iaddend.movable wall is in its
first position.
15. A ventilation structure for relieving differential pressure
across the passenger floor of an aircraft comprising:
a duct formed to duct air between the areas above and below the
floor of the aircraft;
a grille, hingedly mounted to the aircraft which has first and
second positions, the first position restricting the flow in the
duct between the areas above and below the floor of the aircraft;
and
a plenum assembly positioned in said duct behind said grille, said
plenum assembly having at least one movable wall having first and
second sides, said first side of said movable wall being in
pneumatic communication with the above floor area through said
grille so that differential pressure across said floor applies
force to said wall, and bias means for urging said movable wall
into a first position, said movable wall being operatively
connected to said grille to maintain said grille in said first
position thereof when said movable wall is in its first position,
when differential pressure is applied to said movable wall it moves
allowing said grille to rotate to said second position opening said
duct to less restricted flow.
16. The ventilation structure defined in claim 15 including a
second movable wall hingedly connected to said .[.first.]. .Iadd.at
least one .Iaddend.movable wall and operatively connecting said
.[.first.]. .Iadd.at least one .Iaddend.movable wall to said
grille.
17. The ventilation structure defined in claim 16 including stop
means connected to one of said movable walls to restrict the hinge
motion therebetween which would otherwise be caused by said bias
means.
18. The ventilation structure defined in claim 17 wherein said bias
means are connected to urge said .[.first.]. .Iadd.at least one
movable wall .Iaddend.and .Iadd.said .Iaddend.second movable walls
toward the angular relationship position restricted by said stop
means until the differential pressure moves said first movable wall
to a predetermined position different than said restricted
position, after which said bias means urge said .[.first.].
.Iadd.at least one .Iaddend.movable wall away from said restricted
position thereof. .Iadd.
19. A vent for equalizing the pressure on opposite sides of a
structure, said vent comprising:
(a) a movable vent panel which in a first position restricts the
flow from a first side of the structure to a second side
thereof;
(b) a plenum chamber pneumatically connected to the first side of
the structure, said plenum chamber having:
(i) a first movable wall having first and second sides, the first
side of said first movable wall being in pneumatic connection with
the first side of the structure and the second side of said first
movable wall being in pneumatic connection with the second side of
the structure so that differential pressure across the structure
applies force to said first movable wall, and
(ii) a second movable wall hingedly connected to said first movable
wall;
(c) bias means for urging said first movable wall into a first
position;
(d) stop means which restrict the relative motion of said first and
second movable walls under the urging of said bias means when said
first movable wall is in its first position;
(e) said first movable wall being operatively connected to said
movable vent panel to maintain said movable vent panel in its first
position when said first movable wall is in its first position;
and
(f) said bias means being connected to urge said first and second
movable walls toward said stop means until said first movable wall
is moved a predetermined distance from its first position, after
which said bias means urges said first movable wall away from its
first position to a second position which allows said movable vent
panel to move to a second position wherein flow from the first side
of the structure to the second side of the structure is less
restricted,
whereby a predetermined differential pressure across the structure
is capable of overpowering said bias means to move said first
movable wall and said movable vent panel to their second positions.
.Iaddend. .Iadd.
20. A vent for equalizing the pressure on opposite sides of a
structure, said vent comprising:
(a) a movable vent panel movable between a first position which
restricts the flow from a first side of the structure to a second
side thereof and a second position in which the flow from the first
side of the structure to the second side thereof is less
restricted;
(b) a plenum chamber pneumatically connected to the first side of
the structure, said plenum chamber being partially defined by a
first movable wall which has first and second sides and which is
movable between first and second positions, the first side of said
first movable wall being pneumatically connected to the first side
of the structure and the second side of said first movable wall
being pneumatically connected to the second side of the structure,
whereby a differential pressure across the structure applies force
to said first movable wall;
(c) bias means for urging said first movable wall into its first
position;
(d) stop means which define the first position of said first
movable wall;
(e) said first movable wall being operatively connected to said
movable vent panel to maintain said movable vent panel in its first
position when said first movable wall is in its first position and
to move said movable vent panel to its second position when said
first movable wall moves to its second position; and
(f) said bias means being connected to urge said first movable wall
towards its first position until said first movable wall is moved a
predetermined distance from its first position by a differential
pressure across the structure, after which said bias means urges
said first movable wall towards its second position,
whereby a predetermined differential pressure across the structure
overpowers said bias means, move said first movable wall from its
first position to its second position, and move said movable vent
panel from its first position to its second position. .Iaddend.
.Iadd.
21. A vent as recited in claim 20 wherein said movable vent panel
and said first movable wall are both rigid members. .Iaddend.
.Iadd.22. A vent as recited in claim 21 wherein:
(a) said plenum chamber is partially defined by said movable vent
panel;
(b) said movable vent panel pivots about a first hinge between its
first and second positions;
(c) said first movable wall is connected to said movable vent panel
by a second hinge; and
(d) said first movable wall pivots about said second hinge between
its first and second positions. .Iaddend. .Iadd.23. A vent as
recited in claim 22 wherein:
(a) said plenum chamber is partially defined by a second movable
wall having first and second sides;
(b) said second movable wall is composed of a rigid member;
(c) said second movable wall is movable between first and second
positions;
(d) said second movable wall is connected to said first movable
wall by a third hinge;
(e) said second movable wall pivots about said third hinge between
its first and second positions;
(f) the first side of said second movable wall is pneumatically
connected to the first side of the structure, and the second side
of said second movable wall is pneumatically connected to the
second side of the structure, whereby a differential pressure
across the structure applies force to said second movable wall;
(g) said stop means define the first position of said second
movable wall; and
(h) said bias means are connected to urge said second movable wall
towards its first position until said second movable wall is moved
a predetermined distance from its first position by a differential
pressure across the structure, after which said bias means urges
said second movable wall
towards its second position. .Iaddend. .Iadd.24. A vent for
equalizing the pressure on opposite ends of a structure, said vent
comprising:
(a) a movable vent panel which in a first position restricts the
flow from a first side of the structure to a second side
thereof;
(b) a plenum chamber pneumatically connected to the first side of
the structure, said plenum chamber having:
(i) a first movable wall having first and second sides, the first
side of said first movable wall being in pneumatic connection with
the first side of the structure and the second side of said first
movable wall being in pneumatic connection with the second side of
the structure so that differential pressure across the structure
applies force to said first movable wall, and
(ii) a second movable wall hingedly connected to said first movable
wall;
(c) bias means for urging said first movable wall into a first
position;
(d) said first movable wall being operatively connected to said
movable vent panel to maintain said movable vent panel in its first
position when said first movable wall is in its first position;
and
(e) at least one of said movable walls including pneumatic check
valve means which enables flow of air from second side of the
structure into said plenum chamber when said second side of the
structure is at a higher predetermined pressure than said
first,
whereby a predetermined differential pressure across the structure
is capable of overpowering said bias means to move said first
movable wall to a position which allows said movable vent panel to
move to a second position wherein flow from the first side of the
structure to the second
side is less restricted. .Iaddend. .Iadd.25. A vent for equalizing
the pressure on opposite sides of a structure, said vent
comprising:
(a) a movable vent panel movable between a first position which
restricts the flow from a first side of the structure to a second
side thereof and a second position in which the flow from the first
side of the structure to the second side thereof is less
restricted;
(b) a plenum chamber pneumatically connected to the first side of
the structure, said plenum chamber being partially defined by:
(i) a first rigid movable wall which has first and second sides and
which is movable between first and second positions, the first side
of said first movable wall being pneumatically connected to the
first side of the structure and the second side of said first
movable wall being pneumatically connected to the second side of
the structure, whereby a differential pressure across the structure
applies force to said first movable wall, and
(ii) a second rigid movable wall which has first and second sides
and which is movable between first and second positions, the first
side of said second movable wall being pneumatically connected to
the first side of the structure and the second side of said second
movable wall being pneumatically connected to the second side of
the structure, whereby a differential pressure across the structure
applies force to said second movable wall, said second movable wall
being hingedly connected to said first movable wall;
(c) bias means for urging said movable walls into their first
positions;
(d) said first movable wall being operatively connected to said
movable vent panel to maintain said movable vent panel in its first
position when said first movable wall is in its first position and
to move said movable vent panel to its second position when said
first movable wall moves to its second position; and
(e) at least one of said movable walls including check valve means
which permit flow from the first side of the structure into said
plenum chamber when the second side of the structure is at a higher
pressure than the first side of the structure,
whereby a predetermined differential pressure across the structure
overpowers said bias means, moves said movable walls from their
first positions to their second positions, and moves said movable
vent panel
from its first position to its second position. .Iaddend. .Iadd.26.
A vent as recited in claim 25 wherein said movable vent panel is
also a rigid member. .Iaddend. .Iadd.27. A vent as recited in claim
26 wherein:
(a) said plenum chamber is partially defined by said movable vent
panel;
(b) said movable vent panel pivots about the first hinge between
its first and second positions;
(c) said first movable wall is connected to said movable vent panel
by a said second hinge; and
(d) said first movable wall pivots about said second hinge between
its first and second positions. .Iaddend. .Iadd.28. A vent for
equalizing the pressure on opposite sides of a structure, said vent
comprising:
(a) a movable vent panel which in a first position restricts the
flow from a first side of the structure to a second side
thereof;
(b) a plenum chamber pneumatically connected to the first side of
the structure, said plenum chamber having a first movable wall
having first and second sides, the first side of said first movable
wall being in pneumatic connection with the first side of the
structure and the second side of said first movable wall being in
pneumatic connection with the second side of the structure so that
differential pressure across the structure applies force to said
first movable wall;
(c) linkage means hingedly connected to said first movable wall to
form an overcenter linkage therewith;
(d) bias means for urging said first movable wall into a first
position;
(e) stop means which restrict relative motion between said first
movable wall and said linkage means under the urging of said bias
means when said first movable wall is in its first position, said
stop means being mounted on said movable vent panel and including
an abutment surface which engages said first movable wall when said
first movable wall is in its first position; and
(f) said first movable wall being operatively connected to said
movable vent panel to maintain said movable vent panel in its first
position when said first movable wall is in its first position,
whereby a predetermined differential pressure is capable of
overcoming said bias means to move said first movable wall to a
position which allows said movable vent panel to move to a second
position wherein flow from the first side of the structure to the
second side is less restricted.
.Iaddend. .Iadd.29. A vent for equalizing the pressure on opposite
sides of a structure, said vent comprising:
(a) a movable vent panel movable between a first position which
restricts the flow from a first side of the structure to a second
side thereof and a second position in which the flow from the first
side of the structure to the second side thereof is less
restricted;
(b) a plenum chamber pneumatically connected to the first side of
the structure, said plenum chamber being partially defined by a
first movable wall which has first and second sides and which is
movable between first and second positions, a first side of said
first movable wall being pneumatically connected to the first side
of the structure and the second side of said first movable wall
being pneumatically connected to the second side of the structure,
whereby a differential pressure across the structure applies force
to said first movable wall;
(c) linkage means hingedly connected to said first movable wall to
form an overcenter linkage therewith;
(d) bias means for urging said first movable wall into its first
position;
(e) stop means which define the first position of said first
movable wall, said stop means being mounted on said movable vent
panel and including an abutment surface which engages said first
movable wall when said first movable wall is in its first position;
and
(f) said first movable wall being operatively connected to said
movable vent panel to maintain said movable vent panel in its first
position when said first movable wall is in its first position and
to move said movable vent panel to its second position when said
first movable wall moves to its second position,
whereby a predetermined differential pressure across the structure
overpowers said bias means, moves said first movable wall from its
first position to its second position, and moves said movable vent
panel from
its first position to its second position. .Iaddend. .Iadd.30. A
vent as recited in claim 29 wherein said movable vent panel and
said first movable wall are both rigid members. .Iaddend. .Iadd.31.
A vent as recited in claim 30 wherein:
(a) said plenum chamber is partially defined by said movable vent
panel;
(b) said movable vent panel pivots about a first hinge between its
first and second positions;
(c) said first movable wall is connected to said movable vent panel
by a second hinge; and
(d) said first movable wall pivots about said second hinge between
its first and second positions. .Iaddend. .Iadd.32. A vent as
recited in claim 31 wherein:
(a) said linkage means comprises a second movable wall;
(b) said second movable wall partially defines said plenum
chamber;
(c) said second movable wall is composed of a rigid member which
has first and second sides;
(d) said second movable wall is movable between first and second
positions;
(e) said second movable wall is connected to said first movable
wall by a third hinge;
(f) said second movable wall pivots about said third hinge between
its first and second positions;
(g) the first side of said second movable wall is pneumatically
connected to the first side of the structure, and the second side
of said second movable wall is pneumatically connected to the
second side of the structure, whereby differential pressure across
the structure applies force to said second movable wall;
(h) said stop means define the first position of said second
movable wall; and
(i) said bias means are connected to urge said second movable wall
toward its first position until said second movable wall is moved a
predetermined distance from its first position by a differential
pressure across the structure, after which said bias means urge
said second movable wall
towards its second position. .Iaddend. .Iadd.33. A vent for
equalizing the pressure on opposite sides of a structure, said vent
comprising:
(a) a movable vent panel which in a first position restricts the
flow from a first side of the structure to a second side
thereof;
(b) a plenum chamber pneumatically connected to the first side of
the structure, said plenum chamber having a first movable wall
having first and second sides, the first side of said first movable
wall being in pneumatic connection with the first side of the
structure and the second side of said first movable wall being in
pneumatic connection with the second side of the structure so that
differential pressure across the structure applies force to said
first movable wall;
(c) linkage means hingedly connected to said first movable wall to
form an overcenter linkage therewith;
(d) bias means for urging said first movable wall into a first
position;
(e) stop means which restrict relative motion between said first
movable wall and said linkage means under the urgings of said bias
means when said first movable wall is in its first position, said
stop means including a plate connected to said first movable wall
which bears against said linkage means when said first movable wall
is in its first position; and
(f) first movable wall being operatively connected to said movable
vent panel to maintain said movable vent panel in its first
position when said first movable wall is in its first position,
whereby a predetermined differential pressure is capable of
overcoming said bias means to move said first movable wall to a
position which allows said movable vent panel to move to a second
position wherein flow from the first side of the structure to the
second side is less restricted.
.Iaddend. .Iadd.34. A vent for equalizing the pressure on opposite
sides of a structure, said vent comprising:
(a) a movable vent panel movable between a first position which
restricts the flow from a first side of the structure to a second
side thereof and a second position in which the flow from the first
side of the structure to the second side thereof is less
restricted;
(b) a plenum chamber pneumatically connected to the first side of
the structure, said plenum chamber being partially defined by a
first movable wall which has first and second sides and which is
movable between first and second positions, the first side of said
first movable wall being pneumatically connected to the first side
of the structure and the second side of said first movable wall
being pneumatically connected to the second side of the structure,
whereby a differential pressure across the structure applies force
to said first movable wall;
(c) linkage means hingedly connected to said first movable wall to
form an overcenter linkage therewith;
(d) bias means for urging said first movable wall into its first
position;
(e) stop means which define the first position of said first
movable wall, said stop means including a plate connected to said
first movable wall which bears against said linkage means when said
first movable wall is in its first position; and
(f) said first movable wall being operatively connected to said
movable vent panel to maintain said movable vent panel in its first
position when said first movable wall is in its first position and
to move said first movable vent panel to its second position when
said first movable wall moves to its second position,
whereby a predetermined differential pressure across the structure
overpowers said bias means, moves said first movable wall from its
first position to its second position, and moves said movable vent
panel from
its first position to its second position. .Iaddend. .Iadd.35. A
vent as recited in claim 34 wherein said movable vent panel and
said first movable wall are both rigid members. .Iaddend. .Iadd.36.
A vent as recited in claim 35 wherein:
(a) said plenum chamber is partially defined by said movable vent
panel;
(b) said movable vent panel pivots about a first hinge between its
first and second positions;
(c) said first movable wall is connected to said movable vent panel
by a second hinge; and
(d) said first movable wall pivots about said second hinge between
its first and second positions. .Iaddend. .Iadd.37. A vent as
recited in claim 36 wherein:
(a) said linkage means comprises a second movable wall;
(b) said second movable wall partially defines said plenum
chamber;
(c) said second movable wall is composed of a rigid member which
has first and second sides;
(d) said second movable wall is movable between first and second
positions;
(e) said second movable wall is connected to said first movable
wall by a third hinge;
(f) said second movable wall pivots about said third hinge between
its first and second positions;
(g) the first side of said second movable wall is pneumatically
connected to the first side of the structure, and the second side
of said second movable wall is pneumatically connected to the
second side of the structure, whereby differential pressure across
the structure applies force to said second movable wall;
(h) said stop means define the first position of said second
movable wall; and
(i) said bias means are connected to urge said second movable wall
toward its first position until said second movable wall is moved a
predetermined distance from its first position by a differential
pressure across the structure, after which said bias means urge
said second movable wall
towards its second position. .Iaddend. .Iadd.38. A ventilation
structure for relieving differential pressure across the passenger
floor of an aircraft, said ventilation structure comprising:
(a) a duct formed to duct air between the areas above and below the
floor of the aircraft;
(b) a grille hingedly mounted to the aircraft which has first and
second positions, the first position restricting the flow in the
duct between the areas above and below the floor of the
aircraft;
(c) a plenum assembly positioned in said duct behind said grille,
said plenum assembly having:
(i) a first movable wall having first and second sides, said first
side of said first movable wall being in pneumatic communication
with the above floor area through said grille so that differential
pressure across said floor applies force to said first movable
wall, and
(ii) a second movable wall hingedly connected to said first movable
wall and operatively connecting said first movable wall to said
grille;
(d) bias means for urging said first movable wall into a first
position;
(e) stop means connected to one of said movable walls to restrict
the hinge motion therebetween which would otherwise be caused by
said bias means;
(f) said first movable wall being operatively connected to said
grille to maintain said grille in said first position thereof when
said first movable wall is in its first position; and
(g) said bias means being connected to urge said first and second
movable walls towards the angular relationship position restricted
by said stop means until the differential pressure moves said first
movable wall to a predetermined position different than said
restricted position, after which said bias means urge said first
movable wall away from said restricted position thereof,
whereby, when the differential pressure is applied to said movable
wall, it moves, allowing said grille to rotate to said second
position and opening
said duct to less restricted flow. .Iaddend. .Iadd.39. A
ventilation structure for relieving differential pressure across
the passenger floor of an aircraft, said ventilation structure
comprising:
(a) a duct formed to duct air between the areas above and below the
passenger floor of the aircraft;
(b) a movable vent panel pivotably movable between a first position
which restricts the flow in said duct between the areas above and
below the passenger floor and a second position in which the flow
in said duct between the areas above and below the passenger floor
is less restricted;
(c) a plenum assembly positioned in said duct behind said movable
vent panel, said plenum assembly comprising:
(i) a first movable wall which has first and second sides and which
is movable between first and second positions, the first side of
said first movable wall being pneumatically connected to the above
floor area in the passenger aircraft and the second side of said
movable wall being pneumatically connected to the below floor area
in the passenger aircraft, whereby a differential pressure across
the passenger floor applies force to said first movable wall,
and
(ii) a second movable wall which has first and second sides and
which is movable between first and second positions, the first side
of said second movable wall being pneumatically connected to the
above floor area in the passenger aircraft and the second side of
said second movable wall being pneumatically connected to the below
floor area in the passenger aircraft, whereby a differential
pressure across the passenger floor applies force to said second
movable wall, said second movable wall being hingedly connected to
said first movable wall;
(d) bias means for urging said movable walls into their first
positions;
(e) stop means which define the first position of said first and
second movable walls;
(f) said first movable wall being operatively connected to said
movable vent panel to maintain said movable vent panel in its first
position when said first movable wall is in its first position and
to move said movable vent panel to its second position when said
first movable walls moves to its second position; and
(g) said bias means being connected to urge said first and second
movable walls towards their first positions until said first and
second movable walls are moved by predetermined distances from
their first positions by a differential pressure across the
passenger floor, after which said bias means urge said first and
second movable walls towards their second positions,
whereby a predetermined differential pressure across the passenger
floor overpowers said bias means, moves said first and second
movable walls from their first positions to their second positions,
and moves said movable vent panel from its first position to its
second position. .Iaddend.
.Iadd.0. A ventilation structure as recited in claim 39 wherein
said movable vent panel and said first and second movable walls are
all rigid structures. .Iaddend. .Iadd.41. A ventilation structure
as recited in claim 40 wherein:
(a) said movable vent panel is part of said plenum assembly;
(b) said movable vent panel pivots about a first hinge between its
first and second positions;
(c) said first movable wall is connected to said movable vent panel
by a second hinge; and
(d) said first movable wall pivots about said second hinge between
its first and second positions. .Iaddend. .Iadd.42. A ventilation
structure as recited in claim 41 wherein:
(a) said second movable wall is connected to said first movable
wall by a third hinge and
(b) said second movable wall pivots about said third hinge between
its
first and second positions. .Iaddend. .Iadd.43. A ventilation
structure as recited in claim 39 wherein at least one of said
movable walls includes pneumatic check valve means which permit air
flow from the below floor area in the passenger aircraft to the
above floor area when the below floor area is at a higher pressure
than the above floor area. .Iaddend. .Iadd.44. A ventilation
structure as recited in claim 39 wherein said stop means are
mounted on said movable vent panel and include an abutment surface
which engages said first movable wall when said first movable wall
is in its first position. .Iaddend. .Iadd.45. A ventilation
structure as recited in claim 39 wherein said stop means are
connected to one of said movable walls to restrict the hinge motion
therebetween which would otherwise be caused by said bias means.
.Iaddend. .Iadd.46. A ventilation structure for relieving
differential pressure across a floor in an aircraft which is
divided into a first compartment and a second compartment by the
floor, said ventilation structure comprising:
(a) a duct formed to duct air between the first and second
compartments, said duct comprising a shell member;
(b) a movable vent panel pivotably mounted on said shell member,
said movable vent panel being pivotably movable about a first hinge
in both angular directions from a normal position in which the end
of said movable vent panel remote from said shell member engages
the floor, said movable vent panel having a first side in pneumatic
communication with the first compartment and a second side in
pneumatic communication with the second compartment, said movable
vent panel allowing restricted flow of air between the first and
second compartments when in the normal position;
(c) a first movable wall one end of which is pivotably mounted on a
second hinge on the second side of said movable vent panel
intermediate its ends, said first movable wall having a first side
and a second side;
(d) a second movable wall one end of which is pivotably mounted on
a third hinge on said shell member and the other end of which is
pivotably connected via a fourth hinge to said first movable wall,
said second movable wall having a first side and a second side;
(e) said shell member, said movable vent panel, and said first and
second movable walls at least partly defining a plenum chamber, the
first sides of said first and second movable walls facing said
plenum chamber;
(f) said shell member, said movable vent panel, and said first and
second movable walls being sized and shaped so that, when said
movable vent panel is in its normal position, said fourth hinge is
spaced from a straight line between said second and third
hinges;
(g) said plenum chamber being pneumatically connected to the first
compartment;
(h) the second sides of said first and second movable walls being
pneumatically connected to the second compartment;
(i) bias means for urging said first and second movable walls to
pivot in the direction the first sides of said first and second
movable walls face when said movable vent panel is in its normal
position;
(j) stop means which limit the movement of said first and second
movable walls in the direction the first sides of said first and
second movable walls face; and
(k) said first and second movable walls and said bias means
together constituting an overcenter linkage connecting said movable
vent panel to said shell member,
whereby:
(l) said overcenter linkage and said stop means normally maintain
said movable vent panel in its normal position, but
(m) when a predetermined over pressure in the first compartment is
communicated to said plenum chamber, said first and second movable
walls pivot against the urging of said bias means about said second
and third hinges, respectively, in the direction the second sides
of said first and second movable walls face and said movable vent
panel pivots in the direction the first side of said movable vent
panel faces against the urging of said bias means about said first
hinge until said fourth hinge passes the straight line between said
second and third hinges, after which said bias means causes said
first and second movable walls to continue to pivot in the
direction the second sides of said first and second movable walls
face about said second and third hinges, respectively, and said
movable vent panel to pivot in the direction of the second side of
said movable vent panel faces about said first hinge, permitting
the over pressure in the first compartment to be vented to the
second compartment
through said duct. .Iaddend. .Iadd.47. Apparatus for venting
pressurized air through a hollow wall of a pressurized compartment
of an aircraft, comprising:
a mounting structure;
an apertured return air grille hinged to said mounting structure
for swinging movement from a first position in which a light flow
of return air passes through the grille to a second more open
position in which a greatly increased flow of vent air can enter
the hollow wall past the grille, and
means forming a plenum chamber behind said grille, said means
including two swinging grille actuating plates forming a wall of
said plenum chamber and hinges connecting said plates to the
mounting structure and grille respectively at two spaced locations
and to each other at an intermediate location, in a relation to
swing said grille from said first position to said second position
in response to a reduction in pressure at a downstream side of the
plates;
there being a passage or passages through which said return air can
discharge from said pressurized compartment at a location
downstream of the grille, so that said light flow of return air
follows a path first through the grille and then through said
passage or passages into the
interior of said hollow wall for discharge therefrom. .Iaddend.
.Iadd.48. Apparatus as recited in claim 47 and further comprising a
vent panel located downstream of said grille, said passage or
passages being formed
in said vent panel. .Iaddend. .Iadd.49. Apparatus as recited in
claim 47, in which said grille extends essentially vertically at
said side of the compartment and is hinged at an upper edge thereof
for swinging movement of a lower edge of the grille into said
hollow wall. .Iaddend. .Iadd.50. Apparatus as recited in claim 47,
in which said two swinging plates are in a slightly overcenter
position when said grille is in said first position thereof.
.Iaddend. .Iadd.51. Apparatus as recited in claim 47, in which said
two swinging plates are in a slightly overcenter position when said
grille is in said first position thereof, there being means
yieldingly resisting relative swinging movement of said two grille
actuating plates from said slightly overcenter position. .Iaddend.
.Iadd.52. Apparatus as recited in claim 47, including means
yieldingly urging said two swinging plates pivotally relative to
one another in a direction tending to return said grille to said
first position thereof when said grille is slightly displaced from
its first position. .Iaddend. .Iadd.53. Apparatus as recited in
claim 47, in which said means forming said plenum chamber include a
hollow air confining structure mounted to the rear side of said
grille to receive air therefrom and having an opening through which
air
discharges towards said swinging plates. .Iaddend. .Iadd.54.
Apparatus as recited in claim 47, in which said means forming said
plenum chamber include a hollow air confining structure mounted to
a rear side of said grille and to which one of said plates is
connected pivotally by one of said hinges. .Iaddend. .Iadd.55.
Apparatus as recited in claim 47, in which said means forming said
plenum chamber include a hollow air confining structure mounted to
a rear side of said grille for swinging movement therewith and
having an upper outlet opening through which air flows to said
plates to act thereagainst. .Iaddend. .Iadd.56. Apparatus as
recited in claim 47, in which said means forming said plenum
chamber include a hollow air confining structure mounted to a rear
side of said grille for swinging movement therewith and having an
upper outlet opening through which air flows to said plates to act
thereagainst, one of said hinges connecting one of said plates to
said hollow air confining structure at a lower location, and the
other of said hinges connecting the other of said plates to said
mounting structure at a location spaced above said lower location.
.Iaddend. .Iadd.57. Apparatus for venting pressurized air through a
hollow side wall of a pressurized compartment of an aircraft,
comprising:
a mounting structure;
an apertured return air grille at a side of the compartment;
first hinge means connecting said grille at an upper edge thereof
to said mounting structure for swinging movement into said side
wall of the compartment from a first generally vertically extending
position of the grille in which a light flow of return air passes
through the grille to a second more open position in which a
greatly increased flow of vent air can enter the side wall past a
lower edge of the grille;
two swinging grille actuating plates;
second and third hinge means connecting said two plates to said
mounting structure and said grille respectively for relative
swinging movement about spaced generally horizontal axes; and
fourth hinge means pivotally connecting said two plates to one
another at an intermediate location for relative swinging movement
about a fourth axis in a relation to swing said grille from said
first position thereof to said second position in response to a
reduction in pressure at a downstream side of the plates;
said hinge means and plates being interconnected in a relation
causing said fourth hinge means and its axis to pivot relative to
said second and third hinge means and their axes upon swinging
movement of said grille from said first position thereof to said
second and more open position of the
grille. .Iaddend. .Iadd.58. Apparatus as recited in claim 57, in
which said two plates extend essentially horizontally in a slightly
overcenter position when said grille is in said first position
thereof. .Iaddend. .Iadd.59. Apparatus as recited in claim 57,
including a hollow air confining plenum element connected to a rear
side of said grille for swinging movement therewith and to which
one of said hinge means is attached. .Iaddend. .Iadd.60. Apparatus
as recited in claim 57, in which said mounting structure includes a
frame disposed about said grille and relative to which the grille
swings, and a downwardly and upwardly opening duct projecting
rearwardly from the frame and into which said grille swings
rearwardly and containing said plates and said second, third and
fourth hinge means. .Iaddend. .Iadd.61. A vent for equalizing the
pressure on opposite sides of a structure comprising:
a movable vent panel which in a first position restricts the flow
from a first side of the structure to a second side thereof;
and
a plenum chamber pneumatically connected to the first side of the
structure, said plenum chamber having a first movable wall having
first and second sides, said first side of said first movable wall
being in pneumatic connection with the first side of the structure
and said second side of said first movable wall being in pneumatic
connection with the second side of the structure so that
differential pressure across the structure applies force to said
first movable wall, and bias means for urging said first movable
wall into a first position, said first movable wall being
operatively connected to said movable vent panel to maintain said
movable vent panel in said first position thereof when said first
movable wall is in its first position, whereby a predetermined
differential pressure is capable of overpowering said bias means to
move said first movable wall to a position which allows said
movable vent panel to move to a second position wherein flow from
the first side of the structure to the second side is less
restricted. .Iaddend. .Iadd.62. The vent defined in claim 61
including a second movable wall hingedly connected to said first
movable wall, said second movable wall also forming a portion of
said plenum chamber. .Iaddend. .Iadd.63. The vent defined in claim
62 including stop means which restrict the relative motion of said
first and second movable walls under the urging of said bias means
when said first movable wall is in its first position.
.Iaddend. .Iadd.64. The vent defined in claim 63 wherein said bias
means are connected to urge said first and second movable walls
toward said stop means until said first movable wall is moved a
predetermined distance from said first position thereof, afterward
said bias means urge said first movable wall away from said first
position thereof to said position of said first movable wall which
allows said movable vent panel to move to said second position.
.Iaddend. .Iadd.65. The vent defined in claim 64 wherein said
movable vent panel forms a portion of said plenum chamber.
.Iaddend. .Iadd.66. The vent defined in claim 65 including a vent
housing having opposite side walls, said movable vent panel and
said second movable wall being hingedly connected to said vent
housing and said first movable wall being hingedly connected to
said movable vent panel so that said plenum chamber is bounded by
at least a portion of said vent housing including said opposite
side walls, said first and second movable walls, and at least a
portion of said movable vent panel. .Iaddend. .Iadd.67. The vent
defined in claim 66 wherein said bias means includes a spring
connected between said vent structure and said first movable wall,
said spring being preloaded by a predetermined amount when said
first movable
wall is in said first position. .Iaddend. .Iadd.68. The vent
defined in claim 66 wherein said first movable wall is hingedly
connected to said movable vent panel at an intermediate location
thereon, said movable vent panel including a passageway for
allowing restricted flow between the opposite sides of the
structure. .Iaddend. .Iadd.69. The vent defined in claim 66 wherein
said movable vent panel forms a portion of the interior wall
adjacent the cabin floor of a pressurizable aircraft, said movable
vent panel including a dust cover hingedly connected thereto to
prevent flow between the floor and said movable vent panel when
said movable vent panel is in its first position. .Iaddend.
.Iadd.70. The vent defined in claim 62 wherein at least one of said
movable walls includes pneumatic check valve means which enable
flow of air from the second side of the structure into said plenum
chamber when said second side of the structure is at a higher
predetermined pressure than said first. .Iaddend. .Iadd.71. The
vent defined in claim 61 including linkage means hingedly connected
to said first movable wall to form an overcenter linkage therewith.
.Iaddend. .Iadd.72. The vent defined in claim 71 including stop
means which restrict relative motion between said first movable
wall and said linkage means under the urging of said bias means
when said first movable wall is in its
first position. .Iaddend. .Iadd.73. The vent defined in claim 72
wherein said stop means are mounted on said movable vent panel and
include an abutment surface which engages said first movable wall
when said first movable wall is in its first position. .Iaddend.
.Iadd.74. The vent defined in claim 72 wherein said stop means
include a plate connected to said first movable wall which bears
against said linkage when said first movable wall is in its first
position. .Iaddend. .Iadd.75. A ventilation structure for relieving
differential pressure across the passenger floor of an aircraft,
said ventilation structure comprising:
a duct formed to duct air between the areas above and below the
floor of the aircraft;
a grille hingedly mounted to the aircraft, said grille having first
and second positions, the first position restricting the flow in
the duct between the areas above and below the floor of the
aircraft; and
a plenum assembly positioned in said duct behind said grille, said
plenum assembly having a first movable wall having first and second
sides, said first side of said first movable wall being in
pneumatic communication with the above floor area through said
grille so that differential pressure across said floor applies
force to said first movable wall, and bias means for urging said
first movable wall into a first position, said first movable wall
being operatively connnected to said grille to maintain said grille
in said first position thereof when said first movable wall is in
its first position, and, when differential pressure is applied to
said first movable wall, it moves, allowing said grille to rotate
to said second position and opening said duct to less restricted
flow. .Iaddend. .Iadd.76. The ventilation structure as defined in
claim 75 including a second movable wall hingedly connected to said
first movable wall and operatively connecting said first movable
wall to said grille. .Iaddend. .Iadd.77. The ventilation structure
defined in claim 76 including stop means connected to one of said
movable walls to restrict the hinge motion therebetween which would
otherwise be caused by said bias means. .Iaddend. .Iadd.78. The
ventilation structure defined in claim 77 wherein said bias means
are connected to urge said first and second movable walls toward
the angular relationship position restricted by said stop means
until the differential pressure moves said first movable wall to a
predetermined position different than said restricted position,
after which said bias means urge said first movable wall away from
said restricted position thereof. .Iaddend. .Iadd.79. A pressure
relief device in an airplane to provide decompression relief
between a passenger compartment having a double side wall and a
cargo compartment, the device comprising:
a grill;
ductwork to extend from an upper edge of the grill to an outer wall
to form a channel for movement of air between the two compartments;
and
a pivotally mounted valve to extend across to block the channel,
said valve having resilient means sized for holding the valve
closed under normal operating conditions and having perforations
sized to allow pressure equalization across the closed valve in
response to a low pressure differential and to require the valve to
open in response to a high pressure differential. .Iaddend.
.Iadd.80. A pressure relief device as in claim 79 further
comprising:
the valve pivot axis located adjacent the ductwork, and the
resilient means is a spring. .Iaddend. .Iadd.81. A pressure relief
device for an airplane structure having a double wall passenger
compartment and a cargo compartment, the device comprising:
a porous section of an interior wall of the passenger
compartment;
a panel to extend from a top of the porous section towards an outer
wall to form a duct leading to the cargo compartment;
a pivotally mounted valve to extend across to at least partially
close the duct;
a spring to hold the valve closed in normal operation; and
means for permitting air flow through the valve at low pressure
differential between the two compartments but to permit opening the
valve
in response to a sudden high pressure differential. .Iaddend.
.Iadd.82. A pressure relief device as in claim 81 wherein the means
for permitting air flow through the valve comprises having
perforations through the valve. .Iaddend. .Iadd.83. A pressure
relief device in an airplane to provide decompression relief
between a passenger compartment having a double side wall and a
cargo compartment comprising:
a perforated member forming a portion of an inside wall of the
passenger compartment;
a panel to extend from a top of the perforated member toward an
outer wall to form a duct behind the perforated member leading to
the cargo compartment;
a valve pivotally mounted adjacent the panel to extend across to
close off at least a portion of the duct;
a spring to hold the valve in the closed position; and
the valve having perforations sized to permit air flow between the
two compartments through the closed valve in response to a low rate
of differential pressure but not to prevent the valve opening in
response to
a sudden high pressure differential. .Iaddend. .Iadd.84. A method
of providing side wall decompression relief between a passenger
compartment and a cargo compartment of an airplane, the steps
comprising:
positioning a perforated member in a lower sidewall section of an
inside wall of the passenger compartment;
forming a duct behind the perforated member by extending a panel
from the top of the perforated member toward an outside wall;
and
at least partially closing off the duct with a spring closing
pivotally mounted valve having perforations through the valve for
permitting breathing through the valve under normal operating
conditions and opening of the valve in response to a sudden
pressure drop in the cargo compartment. .Iaddend.
Description
BACKGROUND OF THE INVENTION
There are many cases where it is desired to control the flow of
mediums, such as air, from one portion of a structure to another by
restricting the flow thereof, yet provide means to reduce the
restriction of flow during emergency conditions such as those which
might otherwise produce enough force to fail the intervening
structure. An example of this is in the floor of a wide-bodied
aircraft wherein the relatively large volume of the cabin space
above the floor must be vented to the space underneath the cabin
floor when the underfloor volume is rapidly decompressed. If
improperly vented, the relatively small differential pressure which
can be developed across the cabin floor multiplied by the
relatively large floor area can generate sufficient force to fail
the floor and do structural damage to the aircraft. This problem
has been recently recognized by governmental agencies who have
promulgated regulations requiring means in aircraft to assure that
a decompression in any compartment in an aircraft caused by a hole
of at least 20 square feet can be safely accommodated. An obvious
expedient to meet the requirement in such aircraft is to reinforce
the floor so that it can withstand decompression loads
structurally. However, such a solution is impractical in that it
requires extensive retrofit of aircraft presently in service and
increases the weight of the aircraft without a corresponding
increase in efficiency, thus raising the overall cost of the
aircraft to fly.
The prior art solution of providing simple blow-out panels cannot
be used in most instances because their operation can be triggered
by passenger applied forces. Another solution to the problem can be
seen in a patent application by Robert G. McIntyre and Otto J.
Minnich entitled "Frangible Aircraft Floor," U.S. Pat. Ser. No.
578,479 now U.S. Pat. No. 3,938,764 which was filed 19 May 1975,
and is assigned to applicants' assignee. It has been used to
provide venting through a floor structure without decreasing the
useful load-carrying capacity of the aircraft. However, frangible
floors cannot be used in all applications and, therefore, variable
area vents which actuate automatically and are resistant to the
tampering of passengers have been required.
BRIEF DESCRIPTION OF THE INVENTION
The present invention includes a hingedly mounted vent panel which
normally restricts the flow of air between the upper and lower
portions of an aircraft fuselage. The restriction is required so
that the ventilating, air conditioning and heating air flows of the
aircraft can be controlled throughout the cabin. The hinged vent
panel is retained in its normal position by a pair of hinged plates
which are biased overcenter against stops and form one wall of a
differential pressure sensing plenum chamber. Assuming that the
upper portion of the aircraft fuselage is larger than the lower
portion, the plenum chamber is pneumatically connected to remain at
the pressure of the upper portion. When a rapid decrease in
pressure occurs below the floor, a differential pressure is
generated across the two hinged plates which causes them to move
against the biasing means overcenter to release the support for the
vent panel which then swings out of the way to a position which no
longer restricts flow between the upper and lower portions of the
aircraft fuselage. Once the emergency condition is over, the vent
panel is pulled toward its original position until the biasing
means snaps the hinged plates back into their vent panel supporting
position.
Normal venting between the upper and lower portions of the cabin
can occur through openings in the vent panel which are located
below the hinged plates and these can also be used to relieve a
differential pressure condition wherein the low pressure side is
the upper portion of the fuselage. However, in some instances the
air conditioning, heating and ventilating requirements are such
that the restriction is so great that an unwanted differential
pressure in the opposite direction can build up across the floor.
For this reason flapper doors can be included in the hinged plates
which blow upwardly during decompression of the upper portion of
the fuselage to allow relief of the differential pressure without
damage to the floor. This is normally not a critical situation,
however, since the volume above the floor of a passenger aircraft
is normally much greater than the volume below it.
It is therefore a principal object of the present invention to
provide means for relieving differential pressures which may be
undesirably applied across a structural wall or floor
structure.
Another object is to provide venting means which automatically
respond to predetermined differential pressure to open a
larger-than-normal venting area for relieving a differential
pressure.
Another object is to provide vent means which are economical to
manufacture, easy to install, tamper-proof and easy to reset after
their use.
Another object is to provide vent means for an aircraft which blend
in with the general decor of the aircraft and therefore do not
unnecessarily alarm passengers.
Another object is to provide a vent structure which, upon
application of a predetermined differential pressure, self actuates
to open a large vent passageway.
Another object is to provide an emergency venting structure which
opens in response to a sensed differential pressure but not in
response to externally applied force.
These and other objects and advantages of the present invention
will become apparent to those skilled in the art after considering
the following detailed specification which discloses a preferred
embodiment thereof in conjunction with the accompanying drawings
wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cutaway perspective view of a portion of the side wall
of an aircraft having the vent structure of the present invention
installed therein;
FIG. 2 is a side cross-sectional view of the vent structure of FIG.
1 showing its position when it is called upon to vent large amounts
of air from the lower portion of the aircraft fuselage to the upper
portion;
FIG. 3 is a view similar to FIG. 2 wherein a differential pressure
of a predetermined value has been established across the floor
structure of an aircraft and the vent structure is beginning to
open a large vent area; and
FIG. 4 is a view similar to FIGS. 2 and 3 wherein the vent panel
has rotated out of the way to open a large vent area between the
upper and lower portions of an aircraft fuselage to relieve
pressure in the upper portion thereof.
DESCRIPTION OF THE SHOWN EMBODIMENT
Referring to the drawings more particularly by reference numbers,
number 10 in FIG. 1 refers to a vent structure 10 installed in the
interior wall 12 of an aircraft fuselage 14 adjacent the passenger
compartment floor 16 which normally divides the upper fuselage
volume 18 from the lower fuselage volume 20. The vent structure 10
is shown positioned and pneumatically connected for the case where
the upper portion space 18 is larger than the lower portion space
20. Should the opposite be the case, the vent structure 10 could
just as easily be installed below the floor 16 to protect the floor
16 from differential pressures thereacross with the high pressure
being in the space 20. The normal case, however, is for the space
18 to be larger than the space 20 and therefore protection must be
provided to prevent differential pressure across the floor 16 with
the high pressure in the space 18 due to a rupture of the fuselage
integrity below the floor 16.
Air conditioning, heating, and ventilating needs in most aircraft
require that restricted flow occurs throughout the passenger
compartment or upper fuselage space 18 during the flight.
Therefore, the vent structure includes a vent panel 22 which may
include small vent orifices 24 to allow a selected quantity of air
to pass therethrough and through suitably open floor members 26
hidden therebehind. The vent orifices 24 are usually covered by
decorative means such as the grille 28 shown.
The vent structure 10 can be connected to the structure of the
aircraft by any suitable means such as structural side extensions
30 which connect to adjacent structure 32 or by upwardly extending
extensions 34 such as are shown in FIG. 2 which connect the
structure 10 to the interior wall 12. Any other suitable connection
means can also be used.
The vent panel 22 is connected to a shell member 36 by means of a
piano-type hinge 38 which allows the vent panel 22 to swing back
forward fuselage wall 39. The rotation of the vent panel 22 about
the hinge 38 is normally prevented by a pair of plates 40 and 42
which are connected together by a piano-type hinge 44. In addition,
plate 40 is connected to the vent panel by means of the piano hinge
46 and the plate 42 is connected to the shell 36 by means of
another piano hinge 48. Suitable biasing means such as the spring
50 urge the plates 40 and 42 toward vent stops which may be the
separate stops 52 and 54 connected respectively to the vent panel
22 and the shell 36, or the stop member 56. The stop member is
shown connected to plate 40 in position to bear against plate 42 to
prevent further movement of the plates 40 and 42 in the direction
caused by the biasing spring 50 when the structure 10 is in the
position shown in FIG. 2. This, of course, is also accomplished by
the stops 52 and 54 which bear against plates 40 and 42
respectively with included abutment surfaces 55 and 57.
The plates 40 and 42, the shell 36, the portion of the vent panel
22 above hinge 46 and the opposite side walls such as the side wall
58 shown form a plenum chamber 60. The formulation of the plenum
chamber 60 may be assisted by suitable seals incorporated into the
edges of the plates 40 and 42 and the panel 22 or by providing a
suitable resilient sealing material 61 on the sidewalls 58. The
plenum chamber 60 is pneumatically connected to the upper portion
space 18 by means such as the orifice 62 through the panel 22 and
the grille 28. Therefore, the pressure in the plenum chamber 60
remains very close to the pressure in the upper portion space
18.
There are some times when the pressure below the floor 16 needs to
be relieved into the space 18. Therefore, optional flapper doors 64
may be provided which, in conjunction with mating holes 66 in the
plates 40 and 42 enable a flow upward through the plates 40 and 42
as shown by the arrows 68 in FIG. 2. The doors 64 are lightly
spring-loaded closed by means of springs 70 so that they normally
remain in the closed flow obstructing condition shown in FIGS. 1, 3
and 4.
When a differential pressure is established with the high pressure
area above the floor 16, the differential pressure is also applied
across the plates 40 and 42. As shown in FIG. 3, when the
differential pressure reaches a predetermined amount to overcome
the preload in the spring 50, the plates 40 and 42 start to rotate
away from the stops whether they be stops 52 and 54 or stop 56.
This movement eventually drives the plates beyond the overcenter, a
location shown by the phantom hinge line 72 in FIG. 3. From this
point on, the spring 50 causes further folding of the plates 40 and
42 which removes the structural bracing of the vent panel 22
pulling it toward the fuselage wall 39 to remove the flow
restriction and allow a large flow of air indicated by the arrows
74 in FIG. 4. It should be noted that as the vent panel 22 moves
toward the shell 36, a dust member 76 is pulled from under a
resilient covering 78. The member 76 is required to prevent small
fingers, hands, toys, fluids and, in addition, dust from
undesirably falling beneath the floor 16. The member 76 can be
connected to the vent panel by means of a hinge 80 so that it does
not extend into the venting area to unnecessarily restrict the
venting flow. The dust member 76 also restricts flow when the vent
structure 10 is in its normal position so that the orifices 24
properly meter the flow of air conditioning, heating, and other
desirable flows during normal operation of the aircraft.
Alternately, a large cover member 78 could be used instead of the
dust member 76. However, as the arrows 74 show, a large percentage
of the flow is along the floor 16 and anything distrupting the flow
in this area results in a disproportionate flow restriction when
the vent structure 10 is open.
It should be noted that although the vent panel 22 is self
actuating once the hinge 44 goes past the point 72, such need not
be the case and in suitable circumstances the flow itself can push
the panel 22 out of the way.
Once there is no longer need for emergency venting, the panel 22
can be moved from the position shown in FIG. .[.2.]. .Iadd.4
.Iaddend.back to the position shown in FIG. 2 by merely pulling it
toward the passenger compartment until the two plates 40 and 42
snap into their proper overcenter position in readiness for the
next emergency.
Thus, there has been shown and described a novel vent structure
which is suitable for providing emergency venting between the upper
and lower portions of an aircraft fuselage and which fulfills all
of the objects and advantages sought therefor. Many changes,
alterations, modifications, and other uses and applications of the
subject vent structure will become apparent to those skilled in the
art after considering this specification and the accompanying
drawings. All such changes, alterations, uses and modifications
which do not depart from the spirit and scope of the invention are
deemed to be covered by the invention which is limited only by the
claims which follow.
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