close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2407258

код для вставки
Sept. 10, 1946.
a. E. DEL MAR
2,407,258 '
CONTROL FOR PRESSURE CABINS ‘
Filed June 6, 1942
I
2 Sheets-Sheet 1
'
3nventor_,
5181/6‘ f. 554 M40
(Iltorneg
Sept. 10, ‘1946,
Y
B. :E. DEL'MAR'
I
2,407,253 .
CONTROL ‘FOR PRESSURE CABINS
FQi-led June a, 1942
I
'2 Sheets-Sheet 2
' I77 ' ".5
I
‘,
a
496i
9%
'
v
v
8’
v
p
:;
( ?
sap‘jé, i3
/
"
-
4<z"/3
f‘
C’
_
‘
-
. ?eucz Z.‘
/
.
Zinnentor,
DEL MAE
.ByWIQ
I,
ttorneg
Patented Sept. 10, 1946
2,407,258
UNITED STATES PATENT OFFICE
2,407,258
CONTROL FOR PRESSURE CABINS
Bruce E. Del Mar, Los Angeles, Calif., asslgnor
to Douglas Aircraft Company, Inc., Santa
Monica, Calif., a corporation of Delaware
Application June 6, 1942, Serial No. 446,039
31 Claims. (01. 98--1.5)
1
2
My invention relates to means for controlling
pressure in pressure cabins of aircraft, or the
like, and relates particularly to a system having.
therein or associated therewith anticipating
means, whereby the action of the control will be
rendered more sensitive to changes in pressure
of air inside and/0r outside the cabin. This ap
and the outgoing air, with integrating means
whereby the changes or effects occurring in the
plication is a continuation-in-part of my co
responsive elements are integrated and the sum
mation of these effects is imposed on or used to
control the cabin pressure regulator, which cabin
pressure regulator may be any one of many
known types or of the several types suggested in
this disclosure.
,
pending application, Serial No. 429,901, ?led Feb
A further object of the invention is to provide
ruary 7, 1942, for Regulating means for pressure 10 in apparatus for controlling pressure in cabins,
an anticipator system wherein changes in air
cabin.
‘
It is an object of the invention to provide in a
?ow are magni?ed in such a manner that the
system for control of pressure in a substantially
sensitivity of the anticipator system is enhanced.
airtight cabin or chamber, such as a cabin of an
A further object of the invention is to provide
airplane, having as a part thereof elements which 15 in a control device of the character described an
anticipator ‘system providing an anticipator duct
are responsive to changes in the relative flows of
air entering and leaving the cabin or chamber.
having one end thereof communicating with the
As compared to the volume of air entering or
inlet flow of air which is being fed into the cabin
and the other end thereof communicating with
leaving the cabin during a unit of time, the vol
ume of the cabin space is ordinarily quite large, 20 the outlet ?ow of air, with a pressure chamber
the result being that a change in flow into or out
communicating with an intermediate part of
of the cabin does not immediately effect a change
this anticipator duct, said chamber having there
in pressure responsive means forming a part of
in the cabin pressure of sufficient magnitude to
the cabin pressure control device.
actuate pressure responsive elements. For ex
ample, let it be supposed that there is an increase 25
It is a further object of the invention to pro
in the outflow of air through the out?ow opening
vide an anticipator such as described in the pre
ceding paragraph, having its inlet end connected
of the cabin, such as would result in a reduction
to an impact tube and having its outlet end con
in the pressure within the cabin. Owing to the
nected to a venturi, the impact tube being dis
large volume of the cabin, it takes some time for
su?icient air to exhaust in excess of the amount 30 posed in the path of ?ow of the entering air and
the venturi being disposed in the path of ?ow of
of air which is being fed into the cabin, to pro
air leaving the cabin.
duce such change in the cabin pressure to ac
tuate the pressure responsive control means. It
It is a further object of the invention to pro
vide in a control device of the character herein
will be seen therefore that from the time that
the need for a change in the setting of the outlet 35 described, an anticipator system which avoids the
valve occurs and the time the controls are ac
use of a duct or ducts leading from the zone of
the regulator to the inlet and outlet zones of the
tuated, there is a lag. Also, after the controls
pressure cabin, but having means associated with
have been actuated as the result of the change
in pressure conditions which a?ect the cabin, to
the inlet duct and the outlet duct of the cabin, or
operate the motor so as to start closing operation
a plurality of these ducts for producing in the
zone of the regulator, so that the regulator will
of the outlet valve, there will be a lag in the build
up of pressure within the cabin such as may be
be influenced thereby, a simulant cabin pressure
required to discontinue the closing operation of
varying in accordance with relative flows and
the outlet valve. This lag results in a condition
pressures existing in the inlet and outlet paths of
referred to as hunting. My invention reduces 45 ?ow of air entering and leaving the pressure
this hunting action to a, minimum, and therefore
cabin.
has a stabilizing effect on the controls so that the
Further objects and advantages of the inven
pressure within the cabin will be regulated‘so as
tion will be brought out in the following part of
to correspond closely to the schedule for which
the speci?cation,
the control system is set or which is character
Referring to the drawings which are for illus
istic of it.
>
It is an object of the invention to provide a
control system of the character described having
an anticipator with air flow responsive elements
trative purposes, only,
‘
Fig; 1 is a schematic view showing a simple
form of my invention.
‘
Fig. 2 is a diagram illustrating the broad rela
disposed in the paths of flow of the incoming air .55 , tion of parts in the invention.
2,407,258
Fig. 3 is a schematic view showing a form of
the invention and illustrating the manner in
which it may be employed with a plurality of
4
ing circuit 0, with the result that the motor will
be operated in a direction to fully open the valve
l5, whereupon the opening circuit will be inter
rz'ipted by the opening of a limit switch 33. As
the aneroid Ell expands due to the lowering of
pressure within the cabin because of the
opening of the valve, is contactor 36 will be
blowers and outlets.
Fig. i is a diagrammatic view of an alternative
form of my invention.
Fig. 5 is a diagrammatic view showing a fur
moved leftward away from the contact 3! so as
ther embodiment wherein the principles of the
to engage a contact 35 forming a part of the
invention may be employed.
Fig. 6 is a diagrammatic view showing an em 10 closing circuit 0’, which includes the electromag
bodiment of the invention employing mechanical
integrating means.
In Fig. 1 I show a chamber 53 such as the in
terior of an aircraft cabin H.
Means are pro
net
of the relay 22. The aneroid 24 will then
operate to maintain the pressure within the
chamber 19 of the cabin H, constant, through
opening and closing of the circuit 0' resulting
from the movement of the contactor 35 under
control of the aneroid
this constant control
of cabin pressure being maintained until the
pressure differential between the chamber i i] and
have shown a blower [2 which feeds air into the
the ambient ?ight atmosphere is such as to col
chamber it! through a, duct !3, and an outlet
passage or duct 15 having a valve l5 therein for 20 lapse the capsule 25 and cause the contactor 21
to move leftward out of engagement with the
control of the air which is being discharged from
contact 23 and into engagement with a contact
the cabin. The pressure in the chamber HE! de
37 which is connected to the opening circuit 0’
pends upon the relative values of air in?ow and
through‘ a branch conductor 38. Thereafter the
air out?ow. For example, by increasing the air
differential control means, including the capsule
in?ow without change in the air out?ow, the
25, will act to control the motivating unit 55 so
pressure in the chamber may be increased, or by
as to maintain in the chamber 53 a pressure fol
adjusting the outlet valve IS without change in
lowing a predetermined schedule.
the flow of air into the cabin through the duct
To avoid lag in the response of the regulator
E3, the pressure in the chamber l E] may be varied.
B to changes in air flow or pressure conditions
For operation of the means to vary the rela
which would eventually produce changes in the
tion of the incoming ‘and outgoing’ air ?ows, I
cabin pressure, a chamber I of small size is placed
provide a motivating unit it having a shaft l'i
in a position surrounding the pressure respond
extending therefrom to operate the valve 85.
ing elements 24 and 25. By means of the tube
For driving the shaft ii a motor utilizing ?uid
39 this chamber I is connected with the inlet
energy is provided. Due to the close analogy be
duct i3, and by a tube Gil is connected with the
tween hydraulic motivation and electrical, it will
outlet duct M. From the inlet duct l3 air flows
be understood that in showing an electrical sys
through the tube 3% into the chamber 1, and suc
tem within the motivating unit It equivalent hy
tion occurring at the lower mouth of the tube
draulic means may be employed. A motor I8 is
causes air to be drawn through the tube 48
provided which has driving connection with the
from the chamber I at a rate corresponding in
shaft ll. This motor is of reversible type and has
general to the rate of ?ow outward through the
windings l9 and 26 included respectively in a clos
outlet duct it, but at greatly diminished volume
ing circuit 0 and an opening circuit 0, which cir
due to the great difference in size of the duct
cuits are closed when the contactor 2i of a relay
it and the tube 5.8. The pressure existing in
2'2 is moved either to the left or to the right from
the chamber I is determined by the relative value
the neutral position in which it is shown in Fig.
of the incoming flow and outgoing flow of air
1, whereby a source of power, shown as a bat
through the tubes 3% and Gil, in the same man
tery 23, will be connected with either the wind
ner as the pressure in the chamber It! depends
ing i9 or the winding 2!}.
upon the ‘elation of the incoming flow and out
For control of the motivating unit I 6 I provide
going ?ow through the respective ducts l3 and
a regulator including a sealed evacuated aneroid
but, owing to the fact that the volume of the
23 which responds to a simulated cabin pressure,
chamber I is minute as compared to the volume
as will be hereinafter described. The regulator
of the chamber Ii, a change in the ?ow through
R also includes a means which is responsive to
either the duct 33 or the tube
will immediately
changes in the relation of pressure inside and
produce a change in pressure in ‘the chamber I;
outside the cabin 1!. This means is shown as
whereas, the change in the pressure in the cham
a, capsule 25 having its interior connected
ber i3 is relatively slow. Under conditions of
through a duct 28 with‘ external cabin pressure,
equilibrium, for example, when the aircraft is
or, in other words, with ambient flight pressure
variations to which the cabin H is externally 60 flying along at level flight, the pressure existing
in the chamber I will be substantially the same
exposed.
as the pressure in the cabin ii’), or, in other
When the cabin H is at a low altitude, for
words, will be a simulant of cabin pressure. But,
example-between sea level and eight or ten
when any change occurs so as to disturb this con
thousand feet-the differential pressure applied
dition of equilibrium, such change will be im
to the capsule 25 will be such that it will be rela—
mediately re?ected in a change in pressure in the
tively expanded and will hold a contactor 21 in
chamber I and an immediate response of the
engagement with a contact 28 which isconnected
regulator R.
by a conductor 29 with a contactor 30 connected
It will be noted that the tubes 39 and it com
to the aneroid 24, which, when the cabin pres
rise means which de?ne spaces, the flows and/ or
sure is above a prescribed value, will hold the
pressures in which are responsive to changes in
contactor 30 in engagement with a, contact 3!,
the condition of air in the inlet path of flow of
thereby closing the opening circuit 0' which in
cludes the right hand electromagnet 32 of the
air into the chamber E0 or the outlet path of ?ow
through which air is discharged from the chain
relay 22. As a result of this, the contactor 2|
will be moved rightward so as 'to close the open 75 ‘ber 18. Changes in velocity or pressure of the air
vided for feeding air into the cabin and dis
charging air therefrom in such relation that a
pressure will be built up in the chamber it. I
email
5
6
in these inlet and outlet paths of ?ow will, result
of the duct, and preferably at a point near the
in changes in the pressures and/or ?ows existing
in the tubes 39 and 4B, The values of pressure
and/or flow in the tubes 39 and 40 are integrated
outlet end of the duct 5|.
Associated with the capsule 55 there is a con
trol part 60 which is held in a neutral position
in the chamber“ I. Accordingly, the chamber I
intermediate a pair of spaced contacts 6| and 62
,
»
constitutes an integrating means wherein these
during stabilized conditions of operation.
values are brought together and the summation
Contact 6| is connected by a conductor 63 to
thereof is applied so as to in?uence the operation
the valve closing circuit C’ while contact 62 is
of the regulator R which is representative of a
connected by conductor 64 to the valve opening
number of different types of pressure responsive 10 circuit 0’. The contacts are preferably mounted
regulating means through which control of the
for relative movement to the end that each con
motivating unit l6 may be accomplished.
tact may be spaced varying distances from the
In keeping with the foregoing explanation, Fig.
neutral position of the control member 60. The
2 diagrammatically illustrates the broad concep
control part 60 is grounded as shown and the con
tion of the invention. Therein the cabin II is is tacts 6| and 62 are so connected into the opening
shown as having means l3’ to de?ne a path of
and closing circuits respectively that the rate of
?ow for the air fed into the cabin and means I4’
V climb meter will override or veto the controlling
de?ning a path of flow for air leaving the cabin.
effect of the regulator R if the rate of pressure
In cooperative relation to the paths of ?ow of
change within the cabin because of rapid ascent
air or the air ?ow through these paths, respon 20 or descent of the aircraft exceeds some predeter
sive elements 42 and 43 are placed. The e?ects
mined rate as determined by the relative position
produced in these responsive elements 42 and 43
of the contacts BI and 62.
are transmitted as indicated by dotted lines 44
In order that the pressure existing in the
and at to the integrating unit I which is associ
chamber 41 and in the regulator R may be held
ated with the cabin pressure regulator in such 25 substantially equal to cabin pressure during sta
manner that the integrated effects are imposed
bilized conditions of operation, I provide in one
upon the regulator R, sothat the regulator R will
of the ducts 46 or 51, as may be necessary, an
be caused to act immediately in response to
ori?ce 54’ to compensate for frictional resistance
changes in velocity or pressure occurring in the
or pressure head which may be built up in one
inlet and outlet paths of flow. As indicated by
of these ducts in excess of the friction or pressure
vthe dotted line 46 of Fig. 2, the control function
of the regulator R is transmitted to the motivat
head built up in the other, due to differences in
length, ?ttings, etc. The ori?ce is adjusted or set
ing unit 16 so that suitable operation of the valve
so that the pressure in the chamber 41 will be sub
i5 will be accomplished.
As shown in Fig. 3, the responsive element 42
described with relation to Fig, 2 may comprise
stantially simulated cabin pressure, The impact
tubes 42’ and the venturis 43 magnify the effects
one or more impact or pitot tubes 42' disposed in
one or more inlet ducts l3, and the responsive
means 43 of Fig. 2 may be represented in Fig. 3
sensitivity of the control.
of the changes in the flow or pressure in the ducts
l3, l4, and Ma, thereby greatly enhancing the
In Fig. 4 I show'a form of my invention ‘wherein
as one or more Venturi tubes 43' disposed in one 40 the effects produced in the responsive elements
or more outlets such as the outlets l4 and Ma.
associated with the inlet and outlet paths of
The impact tubes 42’ are connected through
?ow of air are transmitted to an integrating
branch ducts 45 with a duct 46 leading to an
means through use of a medium other than air
integrating chamber 4‘! which connects through
flow or pressure. Therein the inlet duct i3 is
a duct 48 with the pressure regulator R having 45 provided with a venturi 65. The ?ow responsive
control connection 4'0‘ with the motivating unit
means consists of a diaphragm 56 disposed
it. The venturis ‘43’ are connected through
across a chamber 67 having connection, on op
branch, ducts 50 with a duct 5| leading to the in
posite sides of the diaphragm 66, with ducts 58 and
tegrating chamber 41. The branch ducts 45 and
69, connected to the inlet duct H5 at the venturi
50 have therein check valves 52, and the blower
65 and at a point adjacent thereto. The effects
ducts l3 have therein check valves 5 l ', which per
produced in the responsive element as the result
of changes in ?ow of air through the duct l3
mit air to flow in the direction of the associated
consists in changes in position of the diaphragm
and corresponding changes in a rheostat l'll which
ciated ducts cannot occur as the result thereof.
55 in turn effects changes in flow of electric cur
rent through a circuit ‘H. The electrical circuit
In Fig. 3 I have shown the manner in which
‘H includes a variable speed motor 12 which drives
the responsive elements 43' may be disposed in a
at variable speed an air pumping means repre
plurality of outlet ducts, and I also indicate that
sented by a propeller 13, which forces air into
one or more of these outlet ducts, such as the out
arrows so that in event of failure of a blower or
of a valve, improper ?ow of air through the asso
let duct 14a, may comprise a relief valve 53 set so 60 the upper end of a tube or chamber ‘M. Asso
ciated with the outlet duct it of Fig. 4 I have
as to open in response to a predetermined pres
shown means which are substantially duplicates
sure differential between the interior and the
of the parts 65 to 13 above referred to. These
duplicate parts are indicated by the same nu~
shown a feature of my invention pertaining to
merals as previously employed with prime marks
the manner of incorporating a rate of climb meter 65 added thereto. The motor 12’ drives the fan 13’
in the control. This rate of climb meter com
in a direction to draw air from the tube or cham
prises a capsule_55 disposed in a shell 56 having
ber 14, with the result that the pressure pro
a small ori?ce 51 in its wall through which air
duced at the mouth of the tube '55 which leads
under pressure existing in the cabin H1 may ?ow 70 to the regulator R, is a function of the relative
at a relatively slow rate into the interior of the
flows of air into and out of the chamber 14, and
shell. The interior of the capsule ‘55 is connected
varies in accordance with the changes of air flow
through a similarly small ori?ce 5'!’ with a duct
occurring in the ducts l3 and 14.
58 which communicates with" the duct 5| at a
In Fig. 4 I have shown means whereby a sim
point between the chamber 41 and the outlet end 75 ulated cabin pressure is produced in the cham
exterior of the cabin.
Also, in Fig. 3 I have
224072258.
ber ‘it by use of variable speed motors to pro
duce variable flows of rair into and out of the
chamber ‘M. In Fig. 5 I show means whereby
equivalent results are produced in a device hav
ing a constant speed motivating means to operate
constant speed air pressure and air suction pump
ing means. In Fig. 5 I show a chamber ‘M,’ con
nected through a duct it’ with a regulator R.
Air is fed into the chamber 14' through a duct
80 and is withdrawn therefrom through a duct
8|. The duct 2i}v communicates through a valve
83 ,ith a pump‘ chamber 8-’i, and duct 3! com,
municates through a valve 85 with the opposite
end of the chamber 34 de?ning a space 86
wherein fan means 3'? driven at constant speed
by a motor 88 produces suction in the space 8%
8
arranged to swing between‘ control contacts I05
and I06. The leftward end'of the lever 194! is
connected through a movable pivot Nil support
ed by a lever I08 which is connected to the lever
98 by means of a shaft 589.
It' will be perceived that the lever I04 may be
swung with relation to the contacts 105 and Hit
by two separate means; it may be swung by ver
tical movement of the link H33 resulting from
expansion and contraction of the capsule 19!,
or considering the link I83 as a pivotal support
for the'lever 194., this lever may be swung in co
operative relation to the contacts‘ 585 and IE6
by vertical movement of the pivot I31. Clockwise
rotation of the lever {04 is accomplished by either
downward movement of the link m3 or upward
movement of the pivot I01.
A reduction in cabin pressure will result in a
54, the result being that air is urged under pres
downward movement of the link I03 so as to
sure through the pipe 53E} into the chamber 2'61’ and
likewise suction in the space 83 tends to draw 20 carry the rightward end of the lever I04 toward
the Contact I66. Likewise, an increase in ?ow
air from the chamber ‘MY’ through the duct 8%.
outward through the duct it, such as would pro
The valves 33 and 85 have closures 913 and Qi
duce a reduction in pressure in the ‘cabin space,
whereby the respective flows through the ducts
will result in increase of the force acting down
B8 and 85 are varied, thereby varying the pres
and air pressure in the space 89 of the chamber
sure produced in the chamber ‘iii’. The di~
aphragms '58 and 5%’ of Fig. 4 are also shown in
Fig. 5, whereby they are connected to the ole
sures Q9 and 9% to move the same, and these di»
wardly on the piston 95', exerting a pull on the
cable 97' to swing the lever 98 downward and
rotate the shaft its in anticlockwise direction so
as to raise the pivot I07 and thereby rotate the
lever tilt in clockwise direction so that its right
aphragms are subjected to pressure differentials
by use of the tubes 63 and 69 and 58’ and 6?!’ 30 ward end will be swung downward toward the
contact its. Therefore, before material reduc
which are connected in the previously described
tion in the cabin pressure has occurred, the an
relation through the venturi 55 and 55’ of the
ticipator system will have caused the contact I64
inlet and outlet ducts i3 and M. The chamber
to move into engagement with the contact I06
85 has relief openings 92 and 93 at the ends
which may form part of a closing circuit C’,
thereof, through which variable amounts of air
such as the circuit 0' shown in Fig. 1, whereby
may pass in accordance with the restrictions
the valve l5 will start to close, thereby reducing
placed on the flows of air through the tubes 86
the outward flow through the duct i4 and re
and 8f by the closures 9t and 9| of the valves
lieving the piston 95’ from the force which caused
83 and 85.
it to move downward, as previously described,
In Fig. 6 I show mechanical integrating means
whereupon the anticipator system will be re
and mechanical linkages whereby the effects pro
turned to its neutral position by the action of
duced in flow responsive members are transmit
resilient means such as springs HI shown as
ted. In Fig. 6 I show an inlet duct It? for feed
being applied to the inner faces of the piston 95
ing air into a pressure cabin, this duct having
a venturi 65 as shown in Figs. 4i- and 5. Simi 45 and 95’.
larly, I have shown outlet duct H; with a venturi
It will be understood that a decrease in flow
through the outlet 14 or an increase in flow
65'. Pressure responsive means 993 and 9d’ are
through the inlet l3 will produce anticipation in
associated with the ducts l3 and ill. these re
sponsive means comprising pistons 85' and 95’
opposite direction from that which has just been
movable in cylinders 35 and 9%’ by pressure‘ dif- _ described by way of illustration, the switch lever
ferentials imposed on opDQSite sides of the pistons
I04 being now rotated in anticlockwise direction
85 and 95’ through ducts Eti—$9 and 7Z8’—5S'.
The respective upward and downward ioi-rces
applied to the pistons 95 and 95’ are transmitted
toward the contact 195 which is connected into
by links or cables 9'? and 9?’ to a lever 93 whic
The
I claim as my invention:
1. In regulating means for an aircraft pressure
cabin, the combination of: supercharging means
including an inlet duct through which air is de
livered into said cabin; an outlet duct leading
from said cabin; a flow regulating valve associ
forms a part of the integrating means I’.
the control circuit 0’ so as to accomplish open
ing of the valve 15.
lever 98 through opposed forces applied thereto
by
downward
the members
in keeping
9'.’ and
with
9?’variations
will swinginupward
the flcws
of air through the ducts i3 and 54. Accordingly,
the positions of movements of the lever 88 and 60 ated with at least one of said ducts; a, servo ap
paratus arranged to control the aperture of said
the parts associated therewith represent or are in
valve; a regulator subjected to cabin pressure and
accordance with the integrations of the effects
produced in the responsive elements 94} and 5353’
also to the di?erential between cabin pressure
and external pressure, adapted to actuate said
by changes in flow or pressure in the ducts t3
and Ill. These integration; are imposed on a rec
ulator by use of mechanical means. To illus
trate this, I have shown a regulator comprising
a differential unit 58E) having a capsule till, the
interior of which is connected through a vduct
N32 with ambient air pressure outside the cabin,
the exterior of this capsule HH being exposed to
servo apparatus in response to changes from any
predetermined relation of cabin pressure to ex
ternal atmospheric pressure; and an anticipator
device ‘connected with said regulator and with
said inlet duct and said outlet duct to transmit
to said regulator the effects of changes in air ?ow
cabin pressure. By means of a link I63 the mov
within said ducts prior to any appreciable re
sponse of cabin pressure to pressure variations
able part of the capsule It! is connected to a
and surges within said ducts.
switch lever “3.4, the rightward end of which is
2. In an aircraft, a cabin adapted to be super
9
2,407,258
charged above the ambient atmospheric pressure,
supercharging means comprising at least one
blower, an inlet duct from said blower to said
cabin, at least one outlet valve for discharging
vitiated air from said cabin, an outlet duct lead
ing from said cabin to said outlet valve, a servo
apparatus arranged to control the aperture of
10
lated cabin pressure’ whereby said regulating
means will act prior to the cabin pressure re
‘ sponding appreciably to ‘pressure variations and
surges in said paths of ?ow.
5. In pressure regulating means for‘an aircraft ‘
pressure cabin, the combination of: air ?ow
means for delivering into and taking from the
said outlet valve, a regulator including elements
pressure cabin flows of air in such manner that
responsive respectively to cabin pressure and the
the pressure in said‘cabin will be controlled, said
differential between cabin pressure and ambient 10 air ?ow means de?ning an inlet‘ path of flow for
pressure, adapted to actuate said servo apparatus
charging air and an ‘outlet path of?ow for dis
in response to any departure of cabin pressure
charging air; and regulating means operating to
from a, value functionally correlated to ?ight alti
control said air ?ow means during flight so as to
tude pressure, and an anticipator device, respon
maintain in said cabin a pressure‘ greater than
sive to transient air pressure variations‘ as Well
‘the external atmospheric pressure, said regulat
as to surges in the said inlet duct and in the said
ing means comprising a chamber ‘having an in-'
outlet duct and adapted to accelerate the other;
ternal space which is a fraction oflthe volume of
wise normal functioning of the said regulator, the
said cabin, pressure responsive means exposed to
device comprising a conduit connectingthe regue
the pressure existing in ‘said chamber, means
lator with a region within the said inlet duct ad
actuated by said pressure responsive ‘means for
jacent the blower wherein the air flow pressure
controlling the operation of said air flow means,
is higher than cabin pressure, and a conduit con
and constantly ‘open air ducts connecting said
necting the regulator with a region within the
chamber to said ‘air flow means contiguous to
said outlet duct adjacent the outlet valve wherein
each of said‘paths of ‘flow and operating in con
the air flow pressure is lower than cabin pressure, _ sequence of relative changes in the flows of air
whereby the regulator will respond to ‘pressure
in said paths of ?ow to produce in said chamber
reaction within the conduits prior to the cabin
a simulated cabin pressure whereby said regu
pressure responding appreciably to pressure vari
lating means will act prior to‘ the cabin pressure
ations or surges within the said inlet and outlet
responding appreciably to pressure variations and
ducts.
surges in said paths ‘of ?ow. ' ‘
'
‘
3. In an aircraft, a cabin adapted to be super
6. In an'aircraft ‘the combination of: a cabin
charged and having an outlet, blower means and
adapted to be supercharged; a blower for sup
a delivery‘ duct for supplying air to said cab-in at
plying air to said cabin at a‘ pressure higher than
a pressure higher than that of, the ambient ?ight
that of the ambient ?ight atmosphere; an {air
atmosphere, means, including .a regulator, for ‘J inlet duct from said blower to said cabin; an air
controlling cabin pressure with respect to ?ight
outlet duct from said ‘cabin to the atmosphere;
pressure, and means providing for rapid regulator
a valve in said outlet duct; means for operating
response to trends of cabin pressure variations,
said valve to vary‘ the pressure in said cabin;
said means comprising a conduit connected with
means for controlling said operating means, said
a region Within said delivery duct adjacent the
controlling means including pressure responsive
blower wherein the air flow pressure is higher
means; and‘ means, including means constantly
than cabin pressure, and a conduit connected
responsive to pressure in said ducts for subjecting
with a, region of the cabin adjacent the cabin
saidpressure responsive means to simulated cabin
outlet wherein the air ?ow pressure is lower than
cabin pressure, said regulator having a common‘
control chamber in communication with both of
said conduits and including means in said cham
ber directly and constantly responsive‘to tran
pressure in response to pressure variations due to
surges in said ducts, whereby‘to operate said
Valve and compensate for said'pressure variations
before the same materially change‘ the pressure
within said cabin.
'
‘
“
sient fluctuations in the ?ows in said delivery
'7. Means for regulating the pressure of air in
duct and outlet region respectively, adapted to 50 an aircraft ‘cabin, comprising: air?ow means for
anticipate and prevent corresponding, ?uctua
circulating a flow of airunder pressure through
tions in cabin pressure.
‘
the cabin and including inlet and outlet means;
4. In pressure regulating means for an aircraft
valve means for controlling such flow and thereby
pressure cabin, the combination of: air flow
controlling the ‘cabin pressure; pressure sensitive
means for delivering into and taking from the
regulator means operative to control said valve
pressure cabin ?ows of air in such manner that
means so as to maintain in said cabin a pressure
the pressure in said cabin will be controlled, said
greater than the external atmosphere pressure;
air flow means de?ning an inlet path of flow for
and cabin pressure change anticipating control
charging air and an outlet path of ?ow for dis
means constantly sensitive to transient changes
Charging air; and regulating means operating to 60 in the ?ows in said inlet and outlet means respec
control said air flow means during flight so as to
tively, and operative to effect an integrated re
maintain in said cab-in a pressure greater than
sultant ‘of such transient changes and to utilize
the external atmospheric pressure, said regulat
said resultant to produce in said regulator means
ing means comprising a-chamber having an in
a response to said transient changes before any
ternal space which is a fraction of the volumeof
substantial‘change in cabin pressure can occur
said cabin, pressure responsive means exposed to
the pressure existing in said chamber, means
actuated by said pressure responsive means for
controlling the operation of said air flow means,
and constantly open duct means connected to
said air ?ow means contiguous to each of said
paths of flow and connected to said chamber,
said duct means being operative in consequence
of relative changes in the flows of air in said
paths of flow to produce in said chamber a simu
as a result of said transient changes.
'
8. Means for regulating the pressure of‘air in
aircraft cabin, comprising: airflow means for
circulating a flow of air under pressure through
the cabin including inlet and outlet ‘means; valve
means for controlling said ?ow and thereby con‘
trolling the pressure in the cabin; pressure sensi
tive regulator means for controlling said valve
means so as to maintain in said cabin during
?ight a pressure greater than ambient atmos- ’
2,407,258
ll
12
pheric pressure, said regulator means including
an aircraft cabin, comprising: air?ow means for
circulating a ?ow of air under pressure through
the cabin including inlet and outlet means; valve
means for controlling such flow and thereby con
trolling the pressure in the cabin; pressure sensi
tive regulator means for controlling said valve
means, said regulator means including means de
means de?ning a control chamber in which a
simulated cabin pressure is normally maintained,
a control element in said ‘chamber responsive to
such simulated cabin pressure and another con
trol element in said chamber diiierentially re
sponsive to such simulated cabin pressure and to
ambient atmospheric pressure; and control
means including means constantly responsive to
both gradual and transient changes in ?ow in at 10
least one of said inlet and outlet means, operative
in response to said gradual changes to maintain
said simulated cabin pressure in said chamber
and operative, in response to said transient
changes, to e?ect changes in said simulated cabin 15
pressure and thereby to effect corrective action
in the functioning of said regulator in anticipa
tion and prevention of corresponding changes in
cabin pressure tending to result from said tran-.
sient changes.
'
20
9. Means for regulating the pressure of air in
an aircraft cabin, comprising: air?ow means for
circulating a flow of air under pressure through
‘ the cabin and including inlet and outlet means;
valve means for controlling such flow; pressure
sensitive regulator means for controlling said
valve means and thereby controlling the pressure
?ning a chamber in which a simulated cabin
pressure may be maintained and pressure sensi
tive control means within said chamber; means
for establishing and maintaining said simulated
cabin pressure within said chamber, comprising a
conduit and electrically operated means for forc~
ing a ?uid under pressure through said conduit
into said chamber; and a plurality of electrical
control means responsive to transient changes in
the flows in said inlet and outlet means respec
tively, operative to control the actuation of said
electrically operated means so as to change said
simulated cabin pressure and thereby eilect a cor
rective action upon the operation of said regu
lator before any substantial change in cabin pres
sure can occur as a result of said transient
changes.
12. Mechanism for controlling the pressure of
air in an aircraft cabin, comprising: air?ow
means for circulating a ?ow of air under pres
sure through the cabin and including inlet and
outlet means; valve means for controlling such
ing flight, said regulator including means de?n 30 flow and thereby controlling the pressure in the
cabin; pressure sensitive regulator means for con
ing a control chamber in which said simulated
trolling said valve means, said regulator means
cabin pressures are normally maintained; a con
including a control element responsive diiieren
trol element di?erentially sensitive to changes in
tially to cabin pressure and ambient atmospheric
ambient atmospheric pressure and to changes in
pressure, and an electrical switch operated by
such simulated cabin pressure and a second con
in the cabin so as to maintain said cabin pressure
at a level above that of ambient atmosphere dur
trol element sensitive only to changes in said
said control element; and cabin pressure change
anticipating control mechanism for modifying the
simulated cabin pressure; and control means
action of said control element on said switch, said
comprising means sensitive to changes in the
anticipating mechanism comprising servo mech
?ows in said inlet means and in said outlet means
respectively, said ?ow sensitive means being sen-' 40 anism responsive differentially to transient
changesin the ?ows in said inlet and outlet
sitive both to gradual and to transient flow
means respectively, and mechanical linkage con
changes, and ‘being differentially operative, in
necting said servo mechanism to said switch,
response to said gradual ?ow changes, to main
said anticipating mechanism functioning to effect
tain said simulated cabin pressure in said cham
corrective adjustment of said valve in response to
ber and, in response to said transient changes, to
said transient changes before any substantial
vary the pressure in said control chamber in a
change in cabin pressure can occur as a result of
manner to effect a corrective adjustment of said
said transient changes.
regulator means before any corresponding sub
13. Means for regulating the pressure of the
stantial change in cabin pressure can occur as a
result of said transient changes.
50 atmosphere within an aircraft cabin, comprising:
air?ow means for circulating a flow of air under
10. Means for controlling the pressure of air in
pressure through said cabin and including inlet
an aircraft cabin. comprising: airflow means for
and outlet means; valve means for controlling the
circulating a ?ow of air under pressure through
?ow of air through said air flow means so as to
the cabin and including inlet and outlet means;
valve means for controlling such flow and there 55 control the pressure of said cabin atmosphere; a
pressure responsive regulator connected to said
by controlling the pressure in the cabin; pressure
valve means for operating the same; and means
sensitive regulator means for controlling said
de?ning a relatively small volume path of flow
valve means. said regulator means including
from said inlet to said outlet paralleling the ?ow
means de?ning a chamber in which a simulated
cabin pressure maybe maintained and pressure 60 through said cabin, said regulator including
means sensitive to changes in pressure in said
sensitive control means within said chamber;
small volume path of flow at a point in said path
control means comprising means sensitive to
where pressure will normally approximate pres
changes in the ?ows in said inlet means and in
sure of the cabin atmosphere, whereby said reg
said outlet means respectively, said ?ow sensitive
means being sensitive to both gradual and tran 65 ulator will normally control said valve in re
sponse to variations in cabin pressure, said small
sient ?ow changes and being differentially opera
tive, in response to said gradual ?ow changes, to
volume flow path being adapted to immediately
maintain said simulated cabin pressure in said
chamber and, in response to said transient
changes, to vary the pressure in said control
transmit to said pressure sensitive means pressure
chamber in a manner to effect a corrective ad
justment of said regulator means before any cor
responding substantial change in cabin pressure
can occur as a result of such transient changes.
11. Means for controlling the pressure of air in
changes resulting from transient changes in the
flows in said inlet and outlet, respectively, Where
by to anticipate and prevent corresponding
changes in the pressure of the cabin atmosphere.
14. Means for regulating the pressure of air
Within an aircraft cabin, comprising: airflow
means for circulating a flow of air under pressure
2,407,258
r
14
13“
through the cabin and including inlet and outlet
simulated cabin pressure is normally maintained,
means; valve means for controlling said ?ow so
a control element in said chamber ‘responsive to
as to control the pressure of the air within the
such simulated cabin pressure and another con
cabin; a regulator for controlling said valve
trol element in said chamber differentially re
means, said regulator including a control element 5 sponsive to such simulated cabin pressure and to
responsive to changes in cabin pressure and a
ambient atmospheric pressure; and means for
control
element differentially responsive
to
changes in cabin pressure and in ambient at
mospheric pressure and a pair of electric switches
operated by said control‘elements respectively; a
reversible electric servo motor for actuating said
valve under the control of said regulator, to
gether with electrical connections from said
effecting, as an integrated resultant of fluctua
tions in the flows in said inlet and outlet means
respectively, variations in the pressure in said
chamber and adapted, in response to transient
fluctuations in said ?ows, to e?ect a corrective
adjustment of said regulator in anticipation and
prevention of corresponding changes in cabin
switches to said servo motor; and cabin pressure
pressure tending to result from such transient
change anticipating control means sensitive to 15 ?uctuations.
7
transient changes in the flows in, said inlet and
18. Means for regulating the pressure of air in
outlet means respectively and adapted to produce
an aircraft cabin, comprising: air?ow means for
in said regulator a response to said transient
circulating a flow of air under pressure through
changes before any substantial change in cabin
the cabin and including inlet and outlet means;
pressure can‘ occur as a direct result of said‘ 20 valve means for controlling such flow and there
transient changes.
15. Means for regulating the pressure of air
in an aircraft cabin, comprising: air?ow means
for circulating a ?ow of air under pressure
by controlling the pressure in the cabin; pres
sure sensitive regulator means for controlling
said valve means, said regulator means including
means de?ning a chamber in which a simulated
through the cabin and including inlet and outlet 25 cabin pressure may be maintained and pressure
means; valve means for controlling such flow and
sensitive control means within said chamber;
thereby controlling the cabin pressure; means for
and means for establishing and maintaining said
operating said valve means; a regulator for con
simulated cabin pressure within said chamber,
trolling said operating means; means constantly
comprising conduit means directly connecting
exposed to pressure changes in said inlet means, 30 said chamber to said inlet and outlet means re
means constantly exposed to pressure changes in
spectively and adapted to transmit to said cham
said outlet means, and means in communication
ber both gradual and transient fluctuations in
with the two last named means, adapted to pro
the ?owin said inlet and outlet means respec
duce an integrated resultant of ?uctuations in
tively and to produce in said chamber, as the in
transient flows in said inlet and outlet means re 35 tegrated resultant of said transient changes,
spectively, and to apply said resultant to the ad
pressure variations which Will act through said
justment of said regulator in a manner to antic
pressure sensitive control means to anticipate
ipate and prevent corresponding changes in cabin
and prevent corresponding changes in cabin
pressure tending to result from said transient
?uctuations.
40
19. Means for regulating the pressure of air
16. In a, pressure regulating means for an air
in an aircraft cabin, comprising: airflow means
craft cabin: airflow means for circulating a flow
for circulating a ?ow of air, under pressure
of‘ air under pressure through the cabin and in
through the cabin and including inlet and outlet
cluding inlet and outlet means; valve means for
means; valve means for controlling said flow and
con-trolling such ?ow and thereby controlling the
thereby controlling the pressure in the cabin; ,
pressure in the cabin; pressure sensitive regulator
pressure sensitive regulator means for controle
pressure.
means for controlling said valve means, said reg- V
ulator means including means de?ning a cham
ber in which a simulated cabin pressure may be
maintained and pressure sensitive control means
within said chamber; means in constant com
munication with the flow of air in said inlet
means, means in constant communication with
the flow of air in said outlet means, and means
in communication with the two last. named
means and adapted to en‘ect an integrated re
sultant of transient ?uctuations in the ?ows in
said inlet and outlet means respectively, and to
apply said resultant in the form of variations in
pressure acting on said pressure responsive con 00
trol means, whereby to effect the operation of
said valve in a manner to anticipate and prevent
any substantial change in cabin pressure tending
to result from said transient ?uctuations.
17. Means for regulating the pressure of air in
an aircraft cabin, comprising: airflow means for
circulating a flow of air under pressure through
the cabin and including inlet and outlet means;
valve means for controlling said ?o-w and there
by controlling the pressure in the cabin; pres
sure sensitive regulator means‘ for controlling
said valve means so as to maintain in said cabin
'
,
ling said valve means so as to maintain in said
cabin during ?ight a pressure greater than am
bient atmospheric pressure, said regulator means
including means de?ning a control chamber in
which a simulated cabin pressure is normally
maintained, a control element in said chamber
responsive to such simulated cabin pressure and
another control element in said chamber differ~
entially responsive to such simulated cabin pres
sure and to ambient atmospheric pressure; and
means for establishing and maintaining said
simulated cabin pressure within said chamber,
comprising conduit means directly connecting
said chamber to said inlet and outlet means re
spectively and adapted to transmit to said cham
ber both gradual and transient ?uctuations in
the flows in said inlet and outlet means respec~ ‘
tively and to produce in said chamber, as the
integrated resultant of said transient changes,
pressure variations which will act through said
pressure sensitive control means to anticipate
and prevent corresponding changes in cabin
pressure.
20. In pressure regulating means for a pres-‘
surized aircraft cabin, the combination of : blower
means for supplying air to said cabin at a pres
during flight a pressure greater than ambient at
sure higher (than that‘ of the ambient flight at
mospheric pressure, said regulator means includ
mosphere; an outlet from said cabin; a regulat
ing means de?ning a control chamber in which a 75 ing device for controlling cabin pressure with re
2,407,258:
15
16
spect to ?ight pressure; and means for increas
ing the rapidity of regulator response to trends
atmosphere can occur as a result of said transient
changes.
25. In pressure regulating means for a pres
of cabin pressure variations, said means compris
ing a conduit connecting the regulator with a
surized aircraft cabin, the combination of: air
region within the blower air delivery adjacent to
flow means for circulating a flow of air under
the blower wherein the air flow pressure is higher
than cabin pressure, and a conduit connecting
the regulator with a region adjacent the cabin
outlet wherein the air ?ow pressure is lower than
cabin pressure, whereby pressure ?uctuations at
the blower and cabin outlet are transmitted di
rectly to the regulator.
pressure through the cabin and including pres
surizing inlet means, outlet means, valve means
for controlling the release of air from the cabin
through said outlet means, a reversible electric
motor for operating said valve means, and a
pressure sensitive regulator means including elec
tric switching mechanism for controlling the op
eration of said motor; and anticipating control
means sensitive to ‘transient changes in differ~
ential between quantities of flow in said inlet and
outlet means, respectively, adapted to produce in
21. In pressure regulating means for a Dres~
suriaed aircraft cabin, the combination of: air~
?ow means for circulating a flow of air under
pressure through the cabin and including inlet
and outlet means, valve means for controlling
such flow and pressure sensitive regulator means
for controlling said valve means and thereby con
trolling the pressure in the cabin; and anticipate
ing control means sensitive to transient changes
in differential between quantities of flow in said
inlet and outlet means, respectively, adapted to
said regulator means a response to said transient
changes, modifying the normal response of said
regulator means before any substantial change in
the pressure of the cabin atmosphere can occur
as a result of said transient changes.
26. In pressure regulatinrr means for a pres
surized aircraft cabin, the combination of: air
flow means for circulating a flow of air under
produce in said regulator means a response to
said transient changes before any substantial
pressure through the cabin and including inlet
change in the pressure of the cabin atmosphere
outlet means, valve means for controlling
can occur as a result of said transient changes.
22. In pressure regulating means for a pres
said flow, and pressure sensitive regulator means
for controlling said valve means and thereby
controlling the pressure in the cabin, said regu
surized aircraft cabin, the combination of : air
flow means for circulating the flow of air under
pressure through the cabin and including pres
surizing inlet means, outlet means, valve means
for controlling the discharge of air through said
lator means including means de?ning a pressure
chamber of restricted volume in which there is
maintained air at a pressure, and pressure sen
sitive means within said chamber responding to
changes in the pressure within the chamber and
outlet means so as to control the pressure in the
cabin, and pressure responsive regulator means 35 to changes in ambient flight atmospheric pres
sure; and anticipating control means adapted to
for normally controlling said valve means; and
transmit to said chamber a pressure derived as a
anticipating control means sensitive to transient
diii’erential result of the flows in said inlet and
changes in differential between quantities of flow
outlet means, respectively, whereby to normally
in said inlet and outlet means, respectively,
maintain in said chamber a pressure equal to
adapted to produce in said regulator means a
response to said transient changes before any
substantial change in the pressure of the cabin
cabin pressure and varying in step with cabin
pressure in response to gradual changes in said
inlet and outlet flows, but effective in response to
transient changes in said flows to change the
atmosphere can occur as a result of said transient
changes.
pressure in said chamber in anticipation of cor
23. In pressure regulating means for a pres
responding changes in the pressure of the air
within the cabin and to thereby actuate said reg
surized aircraft cabin, the combination of: air
flow means for circulating a ?ow of air under
ulator means to effect a corrective adjustment of
said valve means so as to anticipate and prevent
pressure through the‘cabin and including inlet
and outlet means, valve means for controlling
said flow, and pressure sensitive regulator means
said corresponding changes in pressure in the
cabin ail‘.
for controlling said valve means and thereby con
trolling the pressure in the cabin; and anticipat
ing control means sensitive to transient changes
in the quantity of ?ow in at least one of said
inlet and outlet means, adapted to produce in
said regulator means a response to said transient
changes before any substantial change in the
pressure of the cabin atmosphere can occur as
a result of said transient changes.
24. In pressure regulating means for a pres
surized aircraft cabin, the combination of : air
?ow means for circulating a ?ow of air under
27. In pressure regulating means for a pres
surized aircraft cabin, the combination of: air
:11
flow means for circulating a flow of air under
pressure through the cabin and including pres
surizing inlet means, outlet means, and valve
means for controlling said flow; and regulating
means including anticipating control means sen
sitive to transient changes in the differential be
tween quantities of now in said inlet and outlet
means, respectively, adapted to adjust said valve
means to compensate for said transient changes
before any substantial change in the pressure
pressure through the cabin and including pres
of the cabin atmosphere can occur as a result
surizing inlet means, outlet means, valve means
of said transient changes.
for controlling said flow, a servo motor for oper
28. Means for regulating the pressure of air in
ating said valve means, and pressure sensitive
an aircraft cabin, comprising: supercharging
regulator means for controlling the operation of
means including an inlet duct through which air
said servo motor and thereby controlling the
is delivered into said cabin and an outlet duct for
pressure in the cabin through said valve means;
and anticipating control means sensitve to tran 70 discharging air from said cabin; a cabin pressure
regulating valve associated with at least one of
sient changes in differential between quantities
said ducts; a servo system arranged to control
of flow in said inlet and outlet means, respective
ly, adapted to produce in said regulator means a
the aperture of said valve; a regulator for con
trolling said servo system; and an anticipator
response to said transient changes before any
system for controlling said regulator, said system
substantial change in the pressure of the cabin
2,407,258
17
'
“
-
being connected with said regulator and with said
inlet and outlet ducts, adapted to transmit to said
regulator the effect of changes of air?ow within
said ducts, in a manner to normally effect the
actuation of said servo system in response to in
changes in the relation of cabin pressure to ex
ternal atmospheric pressure, and being respon
sive to. transient changes in the ?ows in said
ducts in a manner to effect, through said regu
18
change anticipating means comprising means
constantly exposed to pressure changes in said
inlet means, means constantly exposed to pres
sure changes in said outlet means, and means in
communication with both of said last named
means, adapted to produce an integrated result
ant of ?uctuations in transient ?ows in said in
let and outlet means, respectively, and to apply
said resultant to the adjustment of said regulator
lator and servo system, stabilizing adjustment 10 in a manner to anticipate and prevent corre
of said valve aperture in anticipation and pre
sponding changes in cabin pressure tending to
vention of corresponding transient changes in
result from said transient ?uctuations.
pressure in the air within the cabin.
31. Means for regulating the pressure of the
29. Means for regulating the pressure of air in
air within an aircraft cabin, comprising: air ?ow
an aircraft cabin, comprising: air?ow means for
means for circulating air under pressure through
circulating air under pressure to the cabin and
the cabin and including inlet and outlet means;
including inlet and outlet means; a valve for con
trolling the discharge of air through said outlet
means so as to control the pressure of air in the
cabin; regulating means for controlling the aper
ture of said valve, said regulating means in
cluding a pressure responsive element; and cabin
pressure change anticipating means including
?uid conduit means establishing communication
‘ a valve for controlling such circulation and
thereby controlling the pressure of the air with
in the cabin; regulating means for controlling
20 the aperture of said valve, including a pair of
pressure responsive elements and servo mech
anism for transmitting the response of said ele
ments to said valve; and cabin pressure change
anticipating means including conduit means for
between said inlet and outlet means and said 25 directly subjecting said responsive elements to
pressure responsive element and directly subject
variations in pressure resulting directly from
ing said pressure responsive element to pressure
changes in the ?ow in said inlet and outlet
changes resulting from changes in the ?ows of
means, and adapted normally to cause the pres
air in said inlet and outlet means, said anticipat
sure to which said responsive elements are sub
ing means being adapted, in response to transient 30 jected to substantially equal cabin pressure, one
changes in the ?ows in said inlet and outlet
of said pressure responsive elements being sen
means, to produce a stabilizing adjustment of
sitive to both ambient atmospheric pressure and
said valve aperture before corresponding tran
the pressure imposed thereon by said conduit and
sient changes in the pressure of the air in the
the other of said responsive elements being sen
cabin can occur.
‘
35 sitive only to the pressure imposed thereon by
30. Means for regulating the pressure of air in
said conduit means, said anticipating means be
an aircraft cabin, comprising: air?ow means for
ing adapted in response to transient changes in
circulating a ?ow of air under pressure through
the ?ow in said inlet and outlet means to effect
the cabin and including inlet and outlet means;
stabilizing adjustment in the valve before cor
valve means for controlling such flow and there 40 responding transient changes in the pressure of
by controlling the cabin pressure; a regulator for
the air within said cabin can occur.
controlling said valve means; and cabin pressure
BRUCE E. DEL MAR.
Документ
Категория
Без категории
Просмотров
0
Размер файла
1 802 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа