Aircraft provided with a cabin differential pressure warning system

IS 2 360 076 T3

DESCRIPTION

Aircraft with cabin differential pressure alert system

TECHNICAL FIELD

The present invention relates to an aircraft with a cabin differential pressure warning system.

STATE OF THE ART

Aircraft operating at high cruising altitude are typically equipped with a pressurized cabin, which can be accessed through a lockable door. The pressurized cabin guarantees during a flight a pressure inside the cabin largely independent of the respective cruising altitude and the atmospheric pressure of the environment existing there in each case, which remains essentially constant and is tolerable for the passengers of the flight. aircraft, which roughly corresponds to atmospheric air pressure at an altitude of from about 8,000 feet to a maximum of 10,000 feet. Since the atmospheric pressure of the surroundings decreases as the cruising altitude increases, in the pressurized cabin there exists, in the case of cruising altitudes above 10,000 feet, therefore, an increased pressure with respect to the atmospheric pressure of the surroundings ( "Overpressure"). The pressure inside the cabin is generally regulated through an internal pressure regulating device as well as the so-called Flight Management System of the aircraft. When the aircraft is after a flight again in the parked state on the ground, the pressure inside the cabin should again correspond to the atmospheric pressure of the environment, to ensure a safe opening of the door. In other words, there should be no pressure difference between the inside of the cabin and the outside environment. This pressure difference is also referred to in the following as cabin differential pressure.

Since a pressure inside the cabin that is less than the atmospheric pressure of the environment (ie a "sub-pressure") is very dangerous for the structure of the aircraft, aircraft equipped with pressurized cabins generally have protective devices special with one-way valves, which prevent a negative differential pressure (“underpressure”) from being generated. Regardless of this, however, in certain cases, a more or less large cabin differential pressure may still occur after a flight. As a rule, this is an "overpressure" (although low "underpressures" are also possible). If the door is unlocked and opened in this state, it will slam open with uncontrolled speed and a strong airflow is generated with a corresponding suction effect. This leads to a significant risk for people who manipulate the door or are in its direct proximity. In addition, structural damage to the aircraft can occur.

For this reason, aircraft with a pressurized cabin are equipped with a cabin differential pressure warning system, which, for example, recognizes a possible cabin differential pressure in the event of an intentional opening of the door and emits a warning signal. alert. The aircraft crew can then first ventilate the pressurized cabin before opening the door and establish a pressure equalization between the cabin and the outside environment, so that the door can then be opened safely.

Conventional cabin differential pressure warning systems, which indicate the existence of a cabin differential pressure, for example with the help of an alert lamp, are connected to the aircraft's electrical power supply network and receive power from it. of electrical energy. If this electrical power supply network fails, the cabin differential pressure alert system no longer works. Therefore the personnel handling the door can no longer be alerted to the differential pressure in the cabin, and the dangers discussed above still exist. There is a comparable potential for risk in the case of maintenance work, when the electrical power supply to the aircraft is no longer available and the cabin is pressurized.

Document WO 2004022425 (A1) discloses a device for warning of differential pressure when opening a snap closure device of an opening in the fuselage of an aircraft by means of an opening mechanism. An air duct is provided from the side with higher pressure to the side with lower pressure, which can be closed by means of a valve, the valve being controlled with a control lever that is in effective connection with the opening mechanism and generating a signal acoustic when opening the valve and in the event of a differential pressure.

DESCRIPTION OF THE INVENTION

The invention is based on the objective or technical problem of avoiding the disadvantages associated with the generic state of the art as much as possible and to provide an aircraft equipped with a pressurized cabin with an improved cabin differential pressure warning system, more reliable and more secure.

This objective is solved by an aircraft with the characteristics of claim 1.

This aircraft comprises a pressurized cabin with a lockable door, an electrical power supply network as well as a cabin differential pressure alert system with a power supply device for the alert system, autonomous and independent of the network. power supply.

IS 2 360 076 T3

Since in the solution according to the invention the power supply device of the cabin differential pressure warning system is configured completely independent of the electrical power supply network of the aircraft and as a separate autonomous system, it can function reliably even when the electrical power supply network of the aircraft presents alterations or even completely collapses or is out of service. In addition, the cabin differential pressure warning system works with practically no wear. Due to the aforementioned advantages, safety when opening the door of a pressurized car can be considerably improved. In addition, the power supply network of the aircraft in its normal operation (without fault or defect) is not loaded by the cabin differential pressure warning system. Furthermore, it is possible to configure the car differential pressure warning system, including its autonomous and independent power supply device, as a modular, autonomous, independent and separate global unit, and for example to integrate it completely into the door. Interfaces with said power supply network or on-board network of the aircraft are then no longer necessary, or only to a reduced extent. And finally, conventional aircraft can be easily retrofitted with the system according to the invention, being able to use a large number of existing construction elements and construction modules.

By means of the positive properties outlined above, the complexity and potential tendency to failure of the entire system can therefore be reduced and a device that is more constructively and technically simpler, modular, easy to install, inexpensive and more technologically friendly, can be provided. if necessary easy to maintain or replace, increasing the safety and profitability of the aircraft.

Additional advantageous and preferred configuration features of the aircraft according to the invention are the subject of the dependent claims.

A preferred embodiment of the invention with additional configuration details and other advantages is described and set forth in more detail below with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

They show:

Figure 1 a schematic block diagram of an aircraft cabin differential pressure warning system according to the invention;

FIG. 2 a first flow diagram of the cabin differential pressure warning system of FIG. 1; and FIG. 3 a second flow diagram of the cabin differential pressure warning system of FIG. 1.

DESCRIPTION OF A PREFERRED EMBODIMENT EXAMPLE

An aircraft according to the invention comprises a pressurized cabin with a lockable door and a door lock device. The door has a handle or other suitable element, with which the door locking device can be operated for locking or unlocking and the door moved for manual opening or closing or with the aid of an automatic door mechanism. The installation is equipped in this exemplary embodiment with an evacuation ramp. The evacuation ramp must be able to be released quickly in an emergency. To make this possible, the evacuation ramp must first be armed via a control element. In the event of a subsequent opening of the door, it is then activated automatically and the evacuation ramp is immediately released via a release device. In contrast, in normal operation (no emergency), for example when passengers must leave the pressurized cabin through the door with the aircraft parked, the escape ramp must not be armed or released. The aircraft also has a previously generally known electrical power supply network. The aircraft with its components set forth above is not shown in the accompanying drawings for clarity.

Furthermore, the aircraft according to the invention has a cabin differential pressure warning system 2 (hereinafter called by its German abbreviation KDWS), which is represented in figure 1 in a schematic block diagram. The KDWS 2 is fully or essentially fully integrated into the door and has a power supply device for the alert system, autonomous and independent of the aircraft's electrical power supply network. In the present embodiment, the latter comprises an electrical energy generation device, specifically a photovoltaic energy generation device in the form of one or more solar cells 4.

The solar cells 4 are arranged on the door side outside the aircraft and preferably terminate flush with the outside side for aerodynamic reasons. However, they can also be placed inside the door (for example in a so-called window frame) and be covered by a transparent element, which enables the supply of light to the solar cells 4. A placement in the interior area of ​​the pressurized cabin is also conceivable. As is also clear from figure 1, the solar cells 4 are connected through a charge regulator 6 with an accumulator 8, which acts as an intermediate energy storage device.

ES 2 360 076 T3 electrical. The accumulator 8 has a sufficient capacity, adapted to the energy consumption of the KDWS 2, so that there is a sufficient reserve to be able to reliably overcome also dark phases.

As an additional component the KDWS 2 comprises a central differential pressure control device 10 (hereinafter called control device for short), which is connected to the accumulator 8. As indicated in figure 1 by a broken line, the Control device 10 could also be directly connected to charge regulator 6 in the absence of accumulator 8. It is also possible to bypass the accumulator 8 appropriately (see below) and receive the power for the control device 10 directly through the charge controller 6, in case the accumulator 8 fails due to a defect or a fault condition. load too low. The control device 10 may have a data processing device 12 or be operatively coupled to one. The data processing device 12 can be freely programmed and / or if necessary also has permanently pre-programmed components (for example in the form of fixed or interchangeable control modules). The data processing device 2 preferably has an interface, with which it can be connected to an external data processing device (not shown), in order to be able to extract or input data from the data processing device 12 and to adapt the control device 10 in this way optionally to different operating conditions, control routines, aircraft types and supplementary devices.

The KDWS 2 further features a cabin differential pressure sensing device coupled to the control device 10. This has a cabin differential pressure sensor 14 or differential pressure switch (hereinafter referred to as differential pressure sensor 14 for short), which detects a cabin differential pressure AP and upon reaching a predetermined differential pressure threshold value APs provides a signal or switching signal to the control device 10. The differential pressure sensor 14 or differential pressure switch is preferably adjustable, so that if necessary different threshold values ​​of differential pressure 1P can be predetermined._S. For example, a value of ± 2.5 mbar is previously set as a threshold value for differential pressure APs.

The control device 10 is connected to the alert signal emitting device 16, which in this embodiment has both an acoustic and an optical signal emitter. As acoustic signal emitter of the alert signal emitting device 16, for example loudspeakers, sirens, buzzers, beepers, whistles, etc., or a voice generator coupled to a loudspeaker to emit an alert indication can be realized. In case of using a speech generator, then this is preferably programmable and adjustable, so that if necessary alert indications can be issued in different languages. As the optical signal emitter of the warning signal emitting device 16, for example warning lamps or displays with a suitable indication or the like can be used. Combinations of the respective alert signal emitters are also possible.

In addition to the differential pressure sensor 14 mentioned above, the control device 10 is coupled to a detection device 18 for detecting a door condition (hereinafter referred to as door sensor 18 for short). The door sensor 18 recognizes for example an activation state of the door handle (for example door handle activated or not activated) and outputs a corresponding signal to the control device 10. In addition to the door sensor 18, a detection device 20 associated with the control device 10 is provided for detecting a state of the evacuation ramp (hereinafter referred to as evacuation ramp sensor 20 for short). The evacuation ramp sensor 20 recognizes, for example, whether the evacuation ramp has been armed or not, and provides a corresponding signal to the control device 10.

And finally, the control device 20 is furthermore also connected with a detection device 22 for detecting a state of the intermediate energy storage device, that is to say in this case of the accumulator 8. This detection device 22 is hereinafter referred to as short form accumulator sensor 22. This detects in particular the state of charge of the accumulator 8 and provides a signal to the control device 10 upon reaching a predetermined threshold value (representing, for example, a low charge state). The store sensor 22 can also be configured as a store sensor switch, to switch the above-mentioned bypass to the charge controller 6 (see FIG. 1, broken line), if the charge status of the store 8 is too high. Low or accumulator 8 fails due to a system alteration or defect.

Although in this exemplary embodiment all the sensors 14, 18, 20, 22 mentioned are connected to the control device 10, it is basically possible to provide for the door sensor 18 and / or the evacuation ramp sensor 20 and / or the accumulator sensor 22 partial systems and / or separate switching circuits and / or a separate warning signal transmitter. However, this leads to greater manufacturing complexity, so that the previously described variant is preferred. Furthermore the control device 10 can be coupled via an additional interface, not shown, to an indicating instrument in the cockpit and / or the cockpit of the aircraft, for example to provide a pilot and / or a member of the the crew provides information on the cabin differential pressure and the status of the door, the accumulator 8, the charge regulator 6 or the solar cells 4.

Referring to Figure 2, which shows a first flow chart of the KDWS 2 of Figure 1, the operation of the KDWS 2 will now be described by means of a differential pressure alert routine, which is executed in the control device 10, when the aircraft is in a parked state on the ground and the pressurized cabin door must be opened.

IS 2 360 076 T3

Starting from a start function (START), in a first step S1, firstly, by means of the differential pressure sensor 14, the differential pressure AP is detected and it is compared with the previously set differential pressure threshold value APs. If the detected differential pressure AP is greater than the threshold value of differential pressure APs, the routine proceeds to step S2, in which it is checked by means of the evacuation ramp sensor 20 if the evacuation ramp has been armed. If so, the differential pressure alert routine is abandoned and personnel handling the door can be advised in the framework of a subroutine, not shown in figure 2, that the door is still armed and must be deactivated first. This status. If, on the other hand, the evacuation ramp is not armed, the routine goes to step S3.

In step S3 it is checked by means of the door sensor 18 whether the door handle is actuated or not. If not, the routine is abandoned again. If, on the other hand, the door handle is actuated, the control device 10 activates the alert signal emitting device 16 and emits an alert signal as step S4. Personnel operating the door now know that an unacceptable cabin differential pressure exists and that the pressurized cabin must first be vented to equalize the pressure with respect to the surrounding atmosphere, before the door can be opened.

In the differential pressure alert routine described above, the individual routine steps are therefore cascaded through in a succession of consecutive test conditions. In this way the KDWS 2 has self-test capability.

Figure 3 shows a second flow diagram of the KDWS 2 of figure 1 with a routine that monitors the status or charge status of the accumulator 8. Starting from a start function (START), it is checked in a step S5 by means of the Accumulator sensor 22 indicates the state or charge state of the accumulator 8. If the accumulator sensor 22 detects a malfunction of the accumulator 8 or a charge state that is too low, a warning signal is output as step S6. In addition to this, if necessary, by means of the accumulator sensor 22 (when this is configured as a cylinder sensor switch), the connection of the control device 10 with the accumulator can be skipped and the control device 10 with the regulator 6 can be interconnected charge of the solar cells 4, so that the control device 10 is supplied directly with electric current through the charge regulator 6. This last mentioned switching variant is not represented in figure 3. A routine comparable with this accumulator monitoring routine could basically also be provided to check the operating status of the solar cells 4.

The accumulator monitoring routine described above is executed in the present example in the control device 10, the alert signal also being generated in step S6 by the alert signal emitting device 16. Basically, the accumulator monitoring routine could of course also be performed separately from the cabin differential pressure monitoring in a separate device, a separate warning signal emitter could also be used for step S6. On the other hand, the accumulator monitoring routine could also be integrated into the routine of Figure 2 and its cascade-like structure.

The invention is not limited to the above exemplary embodiment. Within the scope of protection, the aircraft according to the invention may rather also adopt a different form of configuration than that specifically described above.

In the previous embodiment, an interface with a charging device that can be connected to the aircraft can be associated with the accumulator 8, optionally and other solar cells 4 and the charge regulator 6. An interface with a charging apparatus inside the aircraft is also conceivable, which is fed through the regular electrical power supply network of the aircraft with electrical energy.

Reference symbols in the claims, description and drawings serve only to better understand the invention and should not limit the scope of protection.

IS 2 360 076 T3

<td colspan="3">Reference symbols list</td>

<td></td><td>They show:</td><td></td>

<td></td><td> 2</td><td>Cab Differential Pressure Alert System</td>

<td rowspan="2"> 5</td><td> 4</td><td>Solar cells)</td>

<td> 6</td><td>Charge regulator</td>

<td></td><td> 8</td><td>Accumulator</td>

<td></td><td> 10</td><td>Differential pressure control device</td>

<td></td><td> 12</td><td>Data processing device</td>

<td></td><td> 14</td><td>Differential pressure sensor</td>

<td> 10</td><td> 16</td><td>Warning signal emitting device</td>

<td></td><td> 18</td><td>Door sensor</td>

<td></td><td> 20</td><td>Evacuation ramp sensor</td>

<td></td><td> 22</td><td>Accumulator sensor</td>

<td></td><td>ΔΡ</td><td>Cabin differential pressure</td>

<td> 15</td><td>APs</td><td>Differential pressure threshold value</td>

<td></td><td>S1-S6</td><td>Routine stages</td>