U.S. patent application number 14/462782 was filed with the patent office on 2014-12-04 for aircraft hydraulic air bleed valve system.
This patent application is currently assigned to Eaton Corporation. The applicant listed for this patent is Rahul Bangar, Sanjeev N. Dhuri. Invention is credited to Rahul Bangar, Sanjeev N. Dhuri.
Application Number | 20140352791 14/462782 |
Document ID | / |
Family ID | 47189978 |
Filed Date | 2014-12-04 |
United States Patent
Application |
20140352791 |
Kind Code |
A1 |
Dhuri; Sanjeev N. ; et
al. |
December 4, 2014 |
AIRCRAFT HYDRAULIC AIR BLEED VALVE SYSTEM
Abstract
An aircraft hydraulic air bleed valve system having an air vent
valve connected to an electronic controller where the opening of
the air vent valve is permitted only when the aircraft is in a
pre-determined flight mode where the aircraft flight mode is
determined by a gyroscope connected to the controller.
Inventors: |
Dhuri; Sanjeev N.; (Pune,
IN) ; Bangar; Rahul; (Pune, IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Dhuri; Sanjeev N.
Bangar; Rahul |
Pune
Pune |
|
IN
IN |
|
|
Assignee: |
Eaton Corporation
Cleveland
OH
|
Family ID: |
47189978 |
Appl. No.: |
14/462782 |
Filed: |
August 19, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13274384 |
Oct 17, 2011 |
8833695 |
|
|
14462782 |
|
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Current U.S.
Class: |
137/1 ;
137/213 |
Current CPC
Class: |
F16K 24/04 20130101;
Y10T 137/7759 20150401; F16K 24/00 20130101; Y10T 137/0379
20150401; Y10T 137/3143 20150401; F01D 17/26 20130101; F15B 21/044
20130101; Y10T 137/0318 20150401 |
Class at
Publication: |
137/1 ;
137/213 |
International
Class: |
F16K 24/04 20060101
F16K024/04; F15B 21/04 20060101 F15B021/04 |
Claims
1. An air bleed valve system for an aircraft hydraulics system
comprising: a gyroscope for measuring the orientation and flight
mode of the aircraft; a gyroscope control system for analyzing
signals from the gyroscope and generating an aircraft signal when
the aircraft is in a flight orientation and flight mode that is
suitable for the bleeding of excess air from the aircraft hydraulic
system; a liquid level sensor mounted in a housing to measure the
level of hydraulic oil within said housing, said liquid level
sensor generating a level signal when said excess is in sufficient
quantity to require bleeding; an air bleed valve controller
electrically connected to said liquid level sensor and to said
gyroscope control system, said air bleed valve controller
generating an activation signal when said aircraft signal and said
level signal indicate that said excess air requires venting; and an
air vent valve mounted in said housing, said air vent valve opening
in response to said activation signal and venting said excess air
outside of said housing.
2. The air bleed valve system of claim 1, wherein said liquid level
sensor includes at least one light emitting diode.
3. The air bleed valve system of claim 1, wherein said liquid level
sensor includes at least one acoustic wave sensor.
4. The air bleed valve system of claim 1, wherein said air bleed
valve controller is integrated with said gyroscope control
system.
5. The air bleed valve system of claim 1, wherein said air bleed
valve controller is integrated with said liquid level sensor.
6. An air bleed valve system for an aircraft comprising: a housing
having a reservoir for containing hydraulic oil and a level of
excess air; a liquid level sensor mounted to said housing for
measuring the level of said hydraulic oil within said reservoir and
then calculating the quantity of excess air and generating a level
signal when said quantity of excess air exceeds a pre-determined
level; an air vent valve mounted in said housing and extending into
said reservoir, said vent valve opening in response to an
activation signal; a gyroscope disposed to measure the orientation
and flight mode of the aircraft, said gyroscope generating an
aircraft signal when said aircraft is in an orientation and flight
mode that is conducive to the venting of said excess air; wherein
said activation signal is transmitted to said air vent valve upon
receipt of said aircraft signal and of said level signal.
7. The air bleed valve system of claim 6 wherein said liquid level
sensor includes at least one light emitting diode.
8. The air bleed valve system of claim 6 wherein said liquid level
sensor includes at least one acoustic wave sensor.
9. (canceled)
10. (canceled)
11. (canceled)
12. (canceled)
13. The air bleed valve system of claim 6, wherein said gyroscope
is a laser ring gyroscope detecting when the aircraft is disposed
in a flight regime that permits said excess air to be vented out of
said reservoir.
14. The air bleed valve system of claim 9, wherein said gyroscope
is a laser ring gyroscope detecting when the aircraft is disposed
in a flight regime that permits said excess air to be vented out of
said reservoir.
15. The air bleed valve system of claim 6, wherein said liquid
level sensor generates said activation signal in response to the
quantity of said excess air exceeding said pre-determined level for
a predetermined length of time and said aircraft being in an
orientation and flight mode that is conducive to the venting of
said excess air.
16. The air bleed valve system of claim 6, wherein said air bleed
valve controller is integrated with said gyroscope control
system.
17. The air bleed valve system of claim 6, wherein said air bleed
valve controller is integrated with said liquid level sensor.
Description
TECHNICAL FIELD
[0001] The exemplary aircraft hydraulic air bleed valve system
relates, in general, to an air bleed valve and in particular to an
aircraft hydraulic air bleed valve system that utilizes a gyroscope
to determine when the aircraft is in a flight mode that is
conducive to the bleeding of air from the hydraulic system and then
permits the activation of an air vent valve.
BACKGROUND
[0002] Air bleed valves are used in aircraft hydraulic systems to
remove unwanted air from the hydraulic circuit prior to the
operation of the high pressure hydraulic system to prevent
unexpected and unwanted operational anomalies. Due to certain
flight regimes, a traditional air bleed valve cannot be used in
certain high performance aircraft, primarily those aircraft used in
military applications. High G loads and inverted flight modes do
not allow the air in the hydraulic system to be bled when
experiencing these flight regimes. Therefore it is necessary to use
sensors to determine when there is air in the hydraulic system and
then electronically open an air vent valve to discharge the air
when the aircraft is flying in a suitable flight mode. Traditional
air bleed valves are usually bled when the pilot manually triggers
the vent valve circuit. Sensors can be used in the air bleed valve
such as a light emitting diode and a photoelectric diode to
indicate that there is air in the hydraulic system and then send a
signal to the pilot that the air vent in the air bleed valve needs
to be activated. Pub. No. US 2010/0319791 A1 to Dirkin et al.
disclose such a system. In the Dirkin system two LEDs and a
phototransistor and three transparent windows are used to sense the
presence of air. When air is detected by an electronic circuit
which is connected to the phototransistor and the LEDs, a signal is
sent to the flight deck so that the vent valve can be activated.
This system is subject to several operational limitations involving
clouding of the windows and failure of the phototransistor.
[0003] Other bleed air systems known in the art include those shown
in U.S. Pat. Nos. 4,524,793 and 4,813,446 to Silverwater et al.
These prior art devices provide for the automatic bleeding of air
at the time of hydraulic pump start up using differential pressure
between the air and the hydraulic oil to move a piston to control
the bleeding process. This system is self activating and is not
controlled by the flight crew or an electronic control system so
the air is automatically vented whenever it is present irrespective
of the aircraft flight mode. This presents a problem in high
performance aircraft since the air cannot be vented in certain
flight regimes. Also, this type of air bleed valve is not as
reliable or dependable as what is needed in the industry for use in
high performance aircraft.
SUMMARY
[0004] The exemplary electronically controlled air bleed valve
system provides for a robust solution for bleeding air from a
hydraulic system whenever the level of air in a reservoir exceeds a
set level and the aircraft in which it is installed is in a flight
mode that is conducive to the bleeding of air from a fluid
reservoir in an accumulator or housing. The quantity of excess air
in the housing is measured with the use of some type of fluid level
sensor such as one that makes use of light emitting diodes and a
photoelectric sensor.
[0005] A gyroscope that includes a gyroscope control system is used
to determine when the aircraft is in a proper orientation and
flight regime for the activation of an air vent valve that is
connected to the reservoir in the housing and opens upon receipt of
an electrical command signal and vents the excess air outside of
the housing and out of the aircraft hydraulic system. The exemplary
air bleed valve system is particularly adaptable for use in
aircraft in that the excess air can be sensed and then vented when
the aircraft is in a suitable flight regime independent of the
aircraft flight instruments. The exemplary system is mounted at the
highest point where the air in the hydraulic system is collected
and will bleed excess air even during flight so long as the
aircraft is in a suitable flight regime or mode. Thus, the system
will bleed air at appropriate times and will not result in leakage
of the hydraulic oil from a reservoir during flight.
[0006] The gyroscope used in the exemplary air bleed system can be
a standalone unit and electrically connected to the air vent valve
controller or it can be physically integrated with the air vent
controller in one package. The gyroscope can be any type of known
gyroscope including what is known as a laser ring gyro so long as
it can determine the aircraft orientation or flight mode to
determine if the aircraft is in an orientation or flight mode that
is suitable for the venting of the excess air from the aircraft
hydraulic system. The gyroscope control system generates an
electronic signal when the aircraft excess air can be vented and
transmits this to another part of the system such as to an air vent
valve controller. Alternatively, the gyroscope control system can
simply send a signal representation of the aircraft's orientation
or flight mode to another circuit or controller and that unit can
determine if the aircraft is in an orientation and flight mode
suitable for the venting of excess air. The air vent valve
controller is electrically connected to the air vent valve and to
the liquid level sensor in addition to the gyroscope control
system. The liquid level sensor generates an electrical signal that
represents the level of the hydraulic oil in the housing and hence,
the quantity of excess air residing above the oil can be
calculated. Once the excess air reaches a given quantity and the
aircraft is in a suitable orientation and flight mode as determined
by the gyroscope, then the air vent valve can be activated and the
excess air is purged from the aircraft hydraulic system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a cross-sectional view of the exemplary aircraft
air bleed valve system;
[0008] FIG. 2 is an alternative functional block diagram of the
exemplary aircraft air bleed valve system; and
[0009] FIG. 3 is a second alternative functional block diagram of
the exemplary aircraft air bleed valve system.
DETAILED DESCRIPTION
[0010] Referring now to the discussion that follows and also to the
drawings, illustrative approaches to the disclosed systems and
methods are shown in detail. Although the drawings represent some
possible approaches, the drawings are not necessarily to scale and
certain features may be exaggerated, removed, or partially
sectioned to better illustrate and explain the present disclosure.
Further, the descriptions set forth herein are not intended to be
exhaustive or otherwise limit or restrict the claims to the precise
forms and configurations shown in the drawings and disclosed in the
following detailed description.
[0011] Moreover, a number of constants may be introduced in the
discussion that follows. In some cases illustrative values of the
constants are provided. In other cases, no specific values are
given. The values of the constants will depend on characteristics
of the associated hardware and the interrelationship of such
characteristics with one another as well as environmental
conditions and the operational conditions associated with the
disclosed system.
[0012] Now referring to FIG. 1 of the drawings, a cross-sectional
view of the exemplary aircraft air bleed valve system 10 is shown.
The air bleed valve system 10 includes an accumulator housing 12
which has a reservoir 24 for containing a quantity of hydraulic oil
22 and a varying quantity of excess air 30. Mounted to the housing
12 is a liquid level sensor 20 which is positioned to sense the
level of the hydraulic oil 22 in the reservoir 24 and is
electrically connected to an air bleed valve controller 14. The air
vent valve 32 is vented outside of the housing 12 and can be opened
and closed in response to an activation signal. The air vent valve
32 is also electrically connected to the air bleed valve controller
14.
[0013] The air bleed valve controller 14 can be a separate
electronic circuit or it can be integrated with the liquid level
sensor 20. The liquid level sensor 20 can use a photoelectric
sensor such as a phototransistor and light emitting diodes LEDs to
measure the level of the hydraulic oil 22 within the reservoir 24.
In the alternative, other types of liquid level sensing systems can
be used such as one the uses liquid contact sensors such as
acoustic wave sensors. Since the volume of the reservoir 24 is
known, the quantity of the excess air 30 can then be determined
based on the measured level of the hydraulic oil 22 in the housing
12.
[0014] A quantity of excess air 30 is shown residing above the
hydraulic oil 22. The electronically activated air vent valve 32 is
mounted to the top section of the reservoir 24 which remains closed
until a signal is generated by the air bleed valve controller 14 to
cause it to open. Upon opening, the air vent valve 32 vents the
excess air 30 to the outside of the housing 12. The vent valve 32
can be a solenoid or a stepper motor or any other type of opening
and closing valve whose state is electronically controlled.
[0015] A gyroscope 16 is shown whose operation is electronically
controlled by a gyroscope control system 18. The gyroscope 16 can
be any type of know gyroscope system such as a laser ring
gyroscope. The gyroscope 16 is used to determine the flight regime
and orientation of the aircraft in which it resides and the
gyroscope control system 18 generates this information and then
transmits it to the air bleed valve controller 14 or processes it
and generates a aircraft mode signal when the excess air can be
bled from the aircraft by opening the air vent valve 32. The
gyroscope control system 18 and the air bleed valve controller 14
and the liquid level sensor 20 electronics can be integrated into
various packages or it can all be integrated into one package and
connected to the aircraft electrical power supply.
[0016] Thus the operation of the exemplary aircraft air valve
system 10 is electronically controlled according to the signals
generated by the gyroscope control system 18 which generates an
aircraft mode signal, and the liquid level sensor 20 which
generates a liquid level signal. The air bleed valve controller 14
processes these signals and generates an activation signal that is
sent to the air vent valve 32 when the excess air, if present in a
sufficient quantity, can be vented out of the reservoir 24.
[0017] The gyroscope control system 18 processes the signals
generated by the gyroscope 16 and generates a separate aircraft
mode signal that is transmitted to the air bleed valve controller
14. The aircraft mode signal can represent the orientation and
flight mode of the aircraft or it can represent that the aircraft
is in an orientation and flight mode of the aircraft that is
suitable for the venting of the excess air 30 and the air vent
valve 32 can be opened if there is sufficient excess air 30 present
in the reservoir 24 as determined within the air bleed valve
controller 14 using software algorithms.
[0018] The quantity of the excess air 30 is determined either
within the liquid level sensor 20 or within the air bleed valve
controller 14. Thus, the exemplary air bleed system 10 provides for
the automatic determination of the quantity of excess air 30 in the
aircraft hydraulic system and then the automatic bleeding of that
excess air 30 only when the aircraft is in a suitable orientation
and flight mode.
[0019] Now referring to FIG. 2 of the drawings, an alternative
functional block diagram of the exemplary air bleed valve system 10
is shown. This functional block diagrams illustrates how the
electronic software operates within the air bleed valve systems 10.
This air valve bleed system 10' is mounted within an aircraft
structure and controls the removal of excess air from the aircraft
hydraulic system. An aircraft electrical power supply 40 is
connected to the gyroscope 16 through the gyroscope control system
18 and provides electrical power to other circuits as well, such as
the liquid level sensor 20 and the air bleed valve controller 14.
The gyroscope 16 can be what is known as a laser ring gyroscope or
any other type of electrically powered or otherwise powered device
that can detect when the aircraft is in a flight regime that will
allow for the venting of the excess air 30 out of the reservoir 24.
The gyroscope control system 18 processes the signals generated by
the gyroscope 16 and then generates either an aircraft signal that
represents the orientation and/or flight mode of the aircraft that
is sent to the air valve controller which is part of the liquid
level sensor 20 or it can generate a aircraft signal that
represents when the aircraft is in an orientation and flight mode
that is conducive to the venting of the excess air 30.
[0020] The liquid level sensor 20 generates a level signal that is
transmitted to the air valve bleed controller 14. By knowing the
level of the hydraulic fluid 22 in the reservoir 24, the quantity
of excess air 30 can be calculated. If the quantity of excess air
30 exceeds a pre-determined level for a pre-determined length of
time, and the aircraft is determined to be in a suitable
orientation and flight mode, then the liquid level sensor 20
generates an activation signal that is sent to the air vent valve
32 to open it and allow the excess air to be vented outside of the
aircraft hydraulic system.
[0021] The gyroscope control system 18 can be physically attached
to the gyroscope 16 or it can be located elsewhere in the aircraft
and only electrically connected to the gyroscope 16. Likewise, the
air bleed valve controller 14 can be separated out from the liquid
level sensor 20 as shown in FIG. 1 and made a separate unit or it
can be made a physical part of the gyroscope controller 18. The
physical packaging of the electronics is up to the designer and
offers extreme flexibility.
[0022] Now referring to FIG. 3 of the drawings, a second
alternative functional diagram of the exemplary aircraft air bleed
system 10 is shown. This functional block diagram illustrates how
the electronic software operates within the air bleed valve system
10. The aircraft electrical power supply 40 supplies electrical
power to the liquid level sensor 20 and to the gyroscope 16 and to
the gyroscope control system 18 and to the air bleed control system
which is integrated into the liquid level sensor 20. The level of
the hydraulic oil 22 in the reservoir 24 is measured by the liquid
level sensor 20. The liquid level sensor 20 is shown having one or
more LEDs that reflect off the top of the hydraulic oil and the
amplitude of the reflected light is measured by a photo detector.
The output of the photo detector is sent to a circuit that
calculates the quantity of the excess air based on the level of the
hydraulic oil and the volume of the reservoir 24. This level signal
is then sent to the gyroscope system controller 18. The gyroscope
system controller 18 interfaces with the gyroscope 16 and process
the output of the gyroscope 16 to determine the orientation and
flight mode of the aircraft. The gyroscope 16 operating in
conjunction with the gyroscope control system 18 determines when
the aircraft is in a suitable orientation and flight mode to permit
the excess air to be safely vented out of the reservoir 24 through
the air vent valve 32. Whenever the aircraft is in this orientation
and flight mode and at the same time the level signal from the
liquid level sensor 20 indicates that the excess air 30 needs to be
vented, then the gyroscope control system 18 send an activation
signal to the air vent valve 32 to cause it to open and vent the
excess air 30 out of the aircraft hydraulic system.
[0023] The present disclosure has been particularly shown and
described with reference to the foregoing illustrations, which are
merely illustrative of the best modes for carrying out the
disclosure. It should be understood by those skilled in the art
that various alternatives to the illustrations of the disclosure
described herein may be employed in practicing the disclosure
without departing from the spirit and scope of the disclosure as
defined in the following claims. It is intended that the following
claims define the scope of the disclosure and that the method and
apparatus within the scope of these claims and their equivalents be
covered thereby. This description of the disclosure should be
understood to include all novel and non-obvious combinations of
elements described herein, and claims may be presented in this or a
later application to any novel and non-obvious combination of these
elements. Moreover, the foregoing illustrations are illustrative,
and no single feature or element is essential to all possible
combinations that may be claimed in this or a later
application.
* * * * *