Patent Description:
Commercial aircraft with a pressurized fuselage and a cabin installed therein usually comprises a plurality of oxygen masks stored inside overhead containers, wherein the containers are opened in emergency cases to allow access to the oxygen masks. During maintenance, the oxygen mask containers are usually checked for their correct function. For this, a door of the oxygen mask container is released through energizing a lock or latch and an operator checks whether all containers open.

However, concepts exist in which a rather small number of oxygen masks is considered inside a respective container, which may even be a single mask per container. Thus, a large number of oxygen mask containers needs to be checked for their function, which includes visual checking, re-arranging the mask after opening the container, and closing the container again. This is a time consuming and cumbersome process.

<CIT> relates to a passenger cabin emergency oxygen device for an aircraft, comprising at least one electrically driven activation device for activating the emergency oxygen device, at least one energy storage device for storing electrical energy and supplying said electrical energy to the at least one activation device, at least one controller adapted for receiving a signal to activate the emergency oxygen device and a source of electrical energy. Said source of electrical energy and said energy storage device are coupled together for substantially constant energy transmission from the source of electrical energy to the energy storage device at a first energy level, said activation device and said controller are coupled together for signal transmission from the controller to the activation device, said activation device and said energy storage device are coupled together for energy transmission from the energy storage device to the activation device at a second energy level which is higher than the first energy level and said activation device, said energy storage device and said controller build one single unit adapted to be inserted into a roof element of an aircraft cabin interior.

It is thus an object of the invention to provide a device for latching a door of an oxygen mask container that allows a simplified and accelerated testing.

This object is met by the device for latching a door of an oxygen mask in an aircraft cabin having the features of independent claim <NUM>. Advantageous embodiments and further improvements may be gathered from the sub claims and the following description.

A device for latching a door of an oxygen mask container in an aircraft cabin is proposed, comprising a door for an oxygen mask container having an inner side, an outer side and a hinge, a first latching device attached to the inner side of the door, a second latching device movable relative to the first latching device to selectively engage or disengage the second latching device, a retaining element attachable to a structural part inside the oxygen mask container, and a test control device arranged on the inner side of the door, wherein the test control device comprises a movable hook element, wherein the test control device is adapted to move the hook element to a first position or to a second position, wherein the hook element is able to engage the retaining element in the first position to restrict an opening degree of the door and wherein the hook element is placed in the second position that when the door is opened, the hook element is moved past the retaining element.

The gist of the invention lies in the capability of switching a latch of a door of an oxygen mask container into a test mode and a normal operation mode. In the test mode, the respective door can be opened by releasing the latch, but the opening degree of the door is clearly restricted. In other words, a normal opening test sequence for checking the correct function of the latch can be conducted without any modification of the latching principle itself. However, the door does not need to swivel into a completely open position, in which the oxygen mask retained in the oxygen mask container partially falls out and in which the oxygen mask does not have to be re-arranged when closing the door again. However, the restricted motion of the door is still sufficiently significant to be visually checked. A test procedure with a device according to the invention can be accomplished within a clearly reduced time frame, it will also be simplified and clearly less cumbersome.

The first latching device and the second latching device are designed complementary to each other, such that they can engage or disengage. In the engaged state, the door is latched. In the disengaged state, the door is unlatched and can be opened. If the door is installed to swivel downwards, it will swivel into an open state once the first and second latching devices are disengaged. The process of engaging and disengaging can be accomplished through a drive unit, which moves one of the first or second latching device.

The first latching device is attached to the inner side of the door and is thus structurally fixed to the door. The second latching device is supported independently from the door. For example, it may be installed on a frame or a wall of the oxygen mask container, in which the door is supported. Preferably the second latching device is connected to a drive unit, which may be coupled with a control unit to release a suitable signal for an emergency opening of the door. The drive unit may comprise a solenoid, an electric motor or the like that is capable of moving the second latching device relative to the first latching device upon receiving the respective signal.

The test control device can be manipulated to either move into the first position or into the second position. In the second position, a normal operation of the oxygen mask container is possible, i.e. the door will open to a full extent once the first and second latching devices disengage. The hook element then always has a sufficient distance to the retaining element to move past the retaining element. In the first position, the test mode is activated and the door cannot open to a full extent, since the hook element engages with the retaining element.

Hence, before testing the latch of the door, the hook element is brought into the second position to initiate the test mode. After conducting the test, the hook element can be moved back into the second position, in which the hook element cannot engage the retaining element any more. Thus, the respective door opening degree will not be restricted and it can be opened fully to release the respective mask.

Moving the hook element can be done by various means, which may include dedicated actuators or by using the drive unit for driving one of the first and second latching device, as explained further below.

In an advantageous embodiment, the test control device is bi-stable and is adapted to hold the hook element in the first position and the second position automatically. In other word, when the hook element has reached the first position or the second position, an external force, a lock or any other means is not required for holding the hook element in its present position. For achieving this, the hook element may be placed on a mechanical linkage or gear that has two states, which both require an external force to be applied to leave the respective state again. The mechanical linkage or gear may thus resemble a kind of mechanical flip-flop.

In an advantageous embodiment, the test control device comprises a control rod swivably supported on the inner side of the door and carrying the hook element, wherein the test control device comprises a resilient element coupled with the control rod and the inner side of the door to hold the control rod either in a first state, in which the hook element is in the first position, or a second state, in which the hook element is in the second position. The control rod may thus be flipped between the first state and the second state, wherein the resilient element, e.g. a spring, holds the control rod in the respective state. The control rod is an elongate and preferably rigid element that is supported like a rocker. It may be made from a metallic or plastic material. It may comprise a flat cross-sectional profile, such that it does not take up much installation space of the mask container.

In an advantageous embodiment, the control rod has a first end and a second end, wherein the control rod is supported on a joint arranged between the first end and the second end, wherein the hook element is arranged on the first end. Thus, when the control rod is flipped from one state into the other, the hook element reaches the first position or the second position, respectively, to assume a desired distance to the retaining element.

In an advantageous embodiment, the control rod has an indicating tab arranged on the second end, wherein the door has an opening, through which the indicating tab protrudes when the hook element is in the first stable position. The indicating tab is used for signaling a person that a test mode is active. By mechanically coupling the indicating tab to the control rod, the position of the indicating tab is directly depending on the state of the device according to the invention.

In an advantageous embodiment, the opening is a slit, through which the control rod can swivel. The slit may preferably be dimensioned to allow the control rod and the indicating tab to reach through. The slit should be placed in a position that allows the control rod swivel without interfering with the retained oxygen mask. The control rod may thus comprise a length that exceeds the available space inside the oxygen mask container in an intermediate position between the first position and the second position. When the control rod is flipped between both positions, it partially travels through the slit.

In an advantageous embodiment, the test control device is arranged in an edge region of the door. Thus, the retaining space for an oxygen mask may be maximized and an interference between the test control device and the oxygen mask is prevented.

The second latching device comprises a linearly moving latching rod, wherein the first latching device comprises a through-hole, into which the latching rod is insertable to latch the door and from which the latching rod is removable to unlatch the door. This is comparable or similar to a common latching mechanism. By moving the second latching device away from the first latching device, the door is unlatched.

The test control device is arranged adjacent to the first latching device, such that the latching rod is able to engage the test control device and move the hook element from the second position into the first position. Thus, an additional active element is not required for initiating the test mode. Simply by moving the already-present second latching device towards the test control device, the test mode is entered. It is preferred if only a dedicated control unit is able to initiate this motion of the latching rod to prevent an undesired activation of the test mode. For example, this may be a test control unit, which is brought into the aircraft merely for conducting a test and only the test control unit is capable of moving the latching rod further through the through-hole to flip the control rod into the first state.

In an advantageous embodiment, the device further comprises a reversal actuator, which is adapted to move the hook element from the first position into the second position. The test control device thus does not need to be flipped into the normal operation mode manually and the test can be accomplished fully automatic.

In an advantageous embodiment, the second latching device comprises a beveled end, wherein the second latching device is adapted to engage the first latching device when the door is in a restrictedly opened state, and to advance the first latching device along the beveled end through further moving the second latching device to pull the door into a closed state. Consequently, after conducting the test, the door may even be closed automatically, which further increases the speed of the test procedure.

In an advantageous embodiment, the device further comprises a door opening sensor attachable to the door or a frame, into which the door is to be arranged, wherein the door opening sensor is adapted to detect an opening degree of the door. The door opening sensor allows to automatically analyze, whether the door opens, e.g. after moving the second latching device away from the first latching device. Handwritten notes are thus not necessary. The door opening sensor may be a distance sensor, such as a capacitive sensor. It may be connected to the above-mentioned test control unit.

The invention further relates to a cabin of an aircraft, comprising a plurality of oxygen mask containers arranged in an installation inside the cabin, wherein the plurality of oxygen mask containers each comprise a device according to the previous description. The installation may e.g. be a hat rack.

In an advantageous embodiment, the oxygen mask containers are designed for retaining at least one oxygen mask. It may be possible to provide oxygen mask containers that only retain a single mask.

Furthermore, the invention relates to an aircraft, comprising at least one cabin of the above description.

In the following, the attached drawings are used to illustrate exemplary embodiments in more detail. The illustrations are schematic and not to scale. Identical reference numerals refer to identical or similar elements. They show:.

<FIG> shows a device <NUM> for latching the door <NUM> of an oxygen mask container <NUM> in an aircraft cabin. The device <NUM> comprises the door <NUM> having an inner side <NUM> and an outer side <NUM>. The door <NUM> is swivably supported on a hinge <NUM> to swivel downwards to open. The size and placement of the door <NUM>, the size of the oxygen mask container <NUM> as well as the placement of the hinge <NUM> are not to scale and are merely schematically illustrated to improve understanding the invention.

A first latching device <NUM> is attached to the inner side <NUM> of the door <NUM> and comprises a through-hole <NUM>, into which a second latching device <NUM> can be inserted. Due to the fixed installation of the first latching device <NUM> to the door <NUM>, both elements always move together. Thus, the door <NUM> is latched if the second latching device <NUM> engages the first latching device <NUM>.

The second latching device <NUM> is exemplarily realized in the form of an elongate element, such as a rod, and has a beveled end <NUM>. It is linearly movable through a first drive unit <NUM>, which may comprise a solenoid or an electric motor. The second latching device <NUM> is movable linearly along its main extension axis. In the state shown in <FIG>, the second latching device <NUM> is inserted into the through-hole <NUM>, such that the first and second latching devices <NUM> and <NUM> engage. The door <NUM> thus remains in the closed position.

Adjacent to the first latching device <NUM>, a test control device <NUM> is provided. It comprises a holder <NUM>, which is attached to the inner side <NUM> of the door <NUM>. On an inner end <NUM> of the holder <NUM>, a control rod <NUM> is swivably supported. The control rod <NUM> comprises a first end <NUM> and an opposite second end <NUM>. A joint <NUM> is arranged between the first end <NUM> and the second end <NUM>, preferably in a center. On the first end <NUM>, a hook element <NUM> is provided, which protrudes away from the control rod <NUM>. On the second end <NUM>, an indicating tab <NUM> is provided, which exemplarily comprises an eye-catching color and which protrudes away from the control rod <NUM>.

Near the first end <NUM>, a resilient element <NUM> in the form of a spring is coupled with the control rod <NUM>. An opposite end of the resilient element <NUM> is coupled with the holder <NUM>. The arrangement of the resilient element <NUM> is chosen such that it is parallel to the control rod <NUM> when the control rod is arranged perpendicularly to the door <NUM>. Thus, the resilient element <NUM> is able to pull the first end <NUM> of the control rod <NUM> either to a side facing to the first latching device <NUM> or to an opposite side. Thus, the controller <NUM> can assume two distinct stable positions, which are maintained by the resilient element <NUM>.

In the illustration of <FIG>, the control rod <NUM>, i.e. the test control device <NUM>, is placed in a state that is referred to as a "second stable position", which does not prevent or limit an opening motion of the door <NUM>. The opposite state is referred to as "first stable position", which is explained in other drawings.

Furthermore, a retaining element <NUM> is shown, which is attached to an inner structure of the oxygen mask container <NUM>, which will be explained in further detail below. A second drive unit <NUM> is provided above the first latching device <NUM> and will also be explained in further detail below.

<FIG> shows the second latching element <NUM> in a retracted state, in which it is linearly moved away from the first latching device <NUM>. Here, it has left the through-hole <NUM>, such that the first latching device <NUM> is not held by the second latching device <NUM> anymore and the door <NUM> opens. It is to be understood, that the door <NUM> can open to a full extent, in which the door <NUM> swivels down gravity-driven and will align substantially vertically inside the aircraft cabin. Consequently, if the device <NUM> is in the second stable position, the door <NUM> can open as usual.

<FIG> shows the device <NUM> in a state comparable to <FIG>, wherein the second latching device <NUM> is about to move in a direction away from the first drive unit <NUM>, such that it is advanced through the through hole <NUM> towards the test control device <NUM>. As shown in <FIG>, the beveled end <NUM> engages the control rod <NUM> in a region between the joint <NUM> and the second end <NUM>, such that the control rod <NUM> swivels about the joint <NUM> about roughly <NUM>°. Thus, the control rod <NUM> assumes the above-mentioned first stable position, in which the hook element <NUM> is placed directly above the retaining element <NUM>.

After flipping the control rod <NUM> as shown, the second latching device <NUM> is retracted in the direction of the first drive unit <NUM> again. Now, as shown in <FIG>, the door <NUM> can be opened, but the opening degree is restricted through the hook element <NUM>, which engages with the retaining element <NUM> shortly after the door <NUM> begins to open. This is particularly useful for testing the function of opening the door <NUM> without the door <NUM> having to swivel open completely. Hence, the mask is completely retained inside the mask container <NUM> while the door <NUM> opens only partially, but clearly visibly.

When flipping the control rod <NUM> from the second position to the first position, the second end <NUM> with the attached indication tab <NUM> moves opposite to the first end <NUM>. Due to an alignment angle of roughly <NUM>° to the control rod <NUM> it remains inside the mask container <NUM> parallel to the closed door <NUM> in the second stable position. However, when flipping the control rod <NUM> over to the first stable position, the indication tab <NUM> is arranged perpendicularly to the door <NUM>. It sticks out through a slit <NUM> in the door <NUM> and is clearly visible from outside the mask container <NUM>. The visibility is further increased through the eye-catching color. This prevents maintaining the first stable position in normal operation of the aircraft.

To further simplify a test procedure, the device <NUM> exemplarily comprises a distance sensor <NUM>, which is able to measure a distance between a part of the door <NUM> in a distance to the hinge <NUM> and an adjacent lining surface <NUM>. A control unit, which is not shown herein, may be coupled to a plurality of first drive units <NUM> and distance sensors <NUM> to automatically flip over the control rods <NUM> of all connected devices <NUM> into the first stable position, initiate opening the doors <NUM>, analyze a distance signal from the distance sensors <NUM>, and save the results.

As shown in <FIG>, the beveled end <NUM> is designed to engage the through-hole <NUM>, since the trough-hole <NUM> has only slightly moved downwards. By extending the second latching device <NUM> through the through-hole <NUM> the beveled end <NUM> slides along a contour of the through-hole <NUM> and the first latching device <NUM> is pushed upwards to close the door <NUM> again. Thus, not only opening the door <NUM> can be initiated, but also closing the door <NUM>.

Reversing the control rod <NUM> from the first stable position into the second stable position is conducted through the second drive unit <NUM>, which pushes the first end <NUM> of the control rod <NUM> away from the retaining element <NUM>. It may thus also be referred to as a reversal actuator. The indicating tab <NUM> moves back into the oxygen mask container <NUM> and a normal opening function for the door <NUM> is possible.

<FIG> show a hat rack <NUM> with a plurality of oxygen mask containers <NUM>, which are exemplarily designed for retaining a single oxygen mask each. Thus, a relatively large number of oxygen mask containers <NUM> and doors <NUM> is provided, which need to be tested. For testing, they may be equipped with the device <NUM> for latching the door <NUM> to conduct an automatic testing function. <FIG> shows the door <NUM> with the slit <NUM>, which is arranged at an edge region <NUM> of the door <NUM>. For certification purposes, the device <NUM> his left out in this illustration.

Claim 1:
Device (<NUM>) for latching a door (<NUM>) of an oxygen mask container (<NUM>) in an aircraft cabin (<NUM>), comprising:
a door (<NUM>) for an oxygen mask container (<NUM>) having an inner side (<NUM>), an outer side (<NUM>) and a hinge (<NUM>),
a first latching device (<NUM>) attached to the inner side (<NUM>) of the door (<NUM>),
a second latching device (<NUM>) movable relative to the first latching device (<NUM>) to selectively engage or disengage the second latching device (<NUM>),
a retaining element (<NUM>) attachable to a structural part inside the oxygen mask container (<NUM>),
a test control device (<NUM>) arranged on the inner side (<NUM>) of the door (<NUM>),
wherein the second latching device (<NUM>) comprises a linearly moving latching rod (<NUM>),
wherein the first latching device (<NUM>) comprises a through-hole (<NUM>), into which the latching rod (<NUM>) is insertable to latch the door (<NUM>) and from which the latching rod (<NUM>) is removable to unlatch the door (<NUM>)
wherein the test control device (<NUM>) comprises a movable hook element (<NUM>),
wherein the test control device (<NUM>) is adapted to move the hook element (<NUM>) to a first position or to a second position, wherein the hook element (<NUM>) is able to engage the retaining element (<NUM>) in the first position to restrict an opening degree of the door (<NUM>) and wherein the hook element (<NUM>) is placed in the second position that when the door (<NUM>) is opened, the hook element (<NUM>) is moved past the retaining element (<NUM>), and
wherein the test control device (<NUM>) is arranged adjacent to the first latching device (<NUM>), such that the latching rod (<NUM>) is able to engage the test control device (<NUM>) and move the hook element (<NUM>) from the second position into the first position.