Breathing assembly for aircraft with strengthened mask securing device

A breathing assembly for aircraft comprising a storage unit, a breathing mask and a releasable securing device. The storage unit has a guiding surface extending perpendicularly to an elevation direction and a maintaining element. The breathing mask comprises a rigid support having a sliding surface adapted to slide in contact with the guiding surface of the storage unit, along a sliding direction between a storage position and an exit position. The support further has a maintaining element. In the storage position, the sliding surface of the support is prevented from moving away from the guiding surface of the storage unit along the elevation direction at the distal end by engagement of the maintaining element of the support with the maintaining element of the storage unit.

CROSS REFERENCE TO RELATED APPLICATION

This application is the U.S. national phase of International Application No. PCT/IB2010/003511 filed on Dec. 23, 2010, and published in English by the World Intellectual Property Organization on Jun. 28, 2012 as International Publication No. WO 2012/085616 A1, the entire contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a breathing assembly essentially comprising a breathing mask and a storage unit for aircraft. Such a breathing assembly is generally placed in a cabin of a civil aircraft and intended to be used by a crew member, generally one of the pilots.

BACKGROUND OF THE INVENTION

Due to aviation regulations, the pilot has to don a breathing mask in some circumstances and has to be able to don the breathing mask within a five second period following an incident occurrence. Therefore, the storage unit has to be placed near the pilot. The storage unit is sometimes fastened to a wall of the cabin. Advantageously, the storage unit is mounted on a seat next to the headrest of the seat.

So, the breathing mask must be secured to the storage unit, even in severe conditions, such as very high acceleration or deceleration, due in particular to a crash, in order to prevent the breathing mask from being thrown into the cabin and possibly hitting the pilot.

Document WO 2009/007794 discloses a breathing assembly for aircraft comprising:a storage unit to be fixed to the aircraft, having a receptacle and an opening, the storage unit further having a guiding surface extending perpendicularly to an elevation direction,a breathing mask to be donned by an aircraft crewmember, the breathing mask comprising a rigid support having a sliding surface adapted to slide in contact with the guiding surface of the storage unit, along a sliding direction, between a storage position and an exit position, the sliding direction being perpendicular to the elevation direction, the support extends along the sliding direction between a proximal end—proximate the opening—and a distal end—at the opposite of the opening along the sliding direction—, anda releasable securing device having a secure state and a release state, wherein when in the secure state the securing device prevents the support from sliding from the storage position towards the exit position and when in the release state the securing device allows the support to slide from the storage position towards the exit position.

SUMMARY OF THE INVENTION

The purpose of this invention is to reduce the risk that the breathing mask unwittingly leaves the storage unit.

For this purpose, according to the invention the support further has at least one maintaining element disposed at the distal end of the support along the sliding direction, the storage unit further has a maintaining element and, in the storage position, the sliding surface of the support is prevented from moving away from (maintained in contact with) the guiding surface of the storage unit along the elevation direction at the distal end by engagement of the maintaining element of the support with the maintaining element of the storage unit.

Thus, movement of the breathing mask relative to the storage unit is reduced, except along the sliding direction. Therefore, the efficiency of the securing device is improved without substantially impeding the sliding of the breathing mask when the user wants to remove the breathing mask from the storage unit. Moreover, this solution avoids increasing the strength of the securing device which would have substantially increased the weight of the breathing mask and would have required more strength to the pilot to place it in the release state.

According to another feature in accordance with the invention, preferably the maintaining element of the support engages the maintaining element of the storage unit along a maintaining length along the sliding direction, and the storage position is spaced from the exit position by a distance at least three times as long as said maintaining length.

Thus, the breathing mask can be tightly maintained relative to the storage unit in the storage position without substantially increasing the friction between the support and the storage unit during sliding of the support between the storage position and the exit position.

According to another feature in accordance with the invention, the maintaining length is preferably lower than 15 millimeters, more preferably lower that 10 millimeters.

Thus, the friction between the support and the storage unit during sliding of the support between the storage position and the exit position is not substantially increased by the engagement of the maintaining element of the support with the maintaining element of the storage unit.

According to another feature in accordance with the invention, in the storage position, along the elevation direction, preferably a clearance lower than 0.5 millimeter, more preferably lower than 0.1 millimeter is placed between the maintaining element of the support and the maintaining element of the storage unit.

Thus, the support is accurately maintained relative to the storage unit in the storage position without requiring low dimensional tolerances and without creating high friction between the support and the storage unit in the storage position.

According to another feature in accordance with the invention, preferably the securing device comprises a lever and a protruding portion and, in the storage position of the support and in the secure state of the securing device, the lever has an abutment portion which abuts against the protruding portion along the sliding direction.

Thus, the user can easily move the securing device between the secure state and the release state, and the securing device efficiently secures the support to the storage when it is in its secure state.

According to supplementary feature in accordance with the invention, preferably in the storage position of the support and in the secure state of the securing device, the sliding surface of the support is prevented from moving away from the guiding surface of the storage unit along the elevation direction at the proximal end by engagement of the protruding portion with the lever.

Thus, in the storage position, movement of the breathing mask relative to the storage unit is further reduced, without impeding the sliding of the support when the securing device is in the release state.

In accordance with the invention, the breathing assembly preferably further has the following supplementary characteristics:the abutment portion of the lever has an edge extending substantially parallel to an edge of the protruding portion,in the secure state of the securing device, along the sliding direction, the edge of the abutment portion of the lever faces the protruding portion and the edge of the protruding portion faces the abutment portion of the lever, andin the secure state of the securing device, in cross section perpendicular to the sliding direction, the whole edge of the abutment portion of the lever is separated by at least 1 millimeter from the edge of the protruding portion.

Thus, the risk that a part of the edge of the abutment portion of the lever is aside instead of being opposite to the protruding portion due to the deformation under high deceleration is substantially reduced. The applicant has noticed that when a part of the edge of the abutment portion of the lever is on the side of the protruding portion, the lever could be moved by the protruding portion towards the release state.

Another feature in accordance with the invention improving the reliability and the robustness of the securing device is that preferably the edge of the abutment portion of the lever has a length at least twice as long as a length of the edge of the protruding portion.

According to another feature in accordance with the invention, the guiding surface of the storage cup preferably comprises two distant portions connected one to the other through a rigid bridge.

Thus, the friction between the guiding surface of the storage unit and the sliding surface of the support is reduced while efficiently maintaining the support relative to the storage unit in the storage position.

According to another feature in accordance with the invention, preferably one amongst the maintaining element of the storage unit and the maintaining element of the support is a groove extending in the sliding direction and the other is a protrusion protruding in a transversal direction perpendicular to the sliding direction and to the elevation direction, the protrusion engaging the groove in the storage position.

This solution is simple and efficient.

According to another feature in accordance with the invention, preferably one amongst the maintaining element of the storage unit and the maintaining element of the support is a pin extending in the sliding direction and the other is a hole, and the pin is inserted in said hole when the rigid support is in the storage position.

This solution is simple and efficient.

According to the invention, the breathing assembly preferably further has the following characteristics:the breathing assembly comprises at least:two pins: a first pin and a second pin and,two holes: a first hole and a second hole, andin the storage position the first pin extends through the first hole and the second pin extends through the second hole,in the exit position the first pin extends away from the first hole and the second pin extends away from the second hole.

Thus, the first pin, the second pin, the first hole and the second hole prevent the breathing mask from rotating around the sliding direction relative to the storage unit when the breathing mask is in the storage position.

According to a supplementary feature in accordance with the invention, in the storage position, the first pin has a first length extending through the first hole and the second pin has a second length extending through the second hole, and the first length is preferably at least ten percent longer than the second length.

Therefore, insertion of the pins in the holes is made easier.

According to another supplementary feature, the breathing mask has preferably the following characteristics:the first pin has a first external section which is circular, the first hole has a first internal section, andthe second pin has a second external section which is circular, the second hole has a second internal section which is elongated (oblong) along a transversal direction perpendicular to the sliding direction and to the elevation direction.

Thus, the support is accurately maintained relative to the storage unit in the storage position without requiring low dimensional tolerances concerning the relative positioning of the first pin, the second pin, the first hole and the second hole in the transversal direction.

According to the invention, the breathing assembly preferably further has the following characteristics:the pin has a cylindrical portion, a tip and a conical portion extending between the cylindrical portion and the tip, andthe hole has a cylindrical portion surrounding the cylindrical portion of the pin when the support is in the storage position.

Thus, the insertion of the pin in the hole is made easier and the maintaining of the breathing mask relative to the support in the storage position is improved without requiring low dimensional tolerances.

According to another feature in accordance with the invention, preferably the pin is in metallic material and the support is in plastic material.

Thus, the rubbing (and the rubbing noise) of the pin against the hole of the support is reduced and the robustness of the breathing assembly is improved.

According to another feature in accordance with the invention, the pin is preferably tight fitted in a separate beam fixed to the storage unit.

This solution is simple, robust and not expansive.

According to another feature in accordance with the invention, preferably the support further has two bevelled lateral walls disposed on opposite sides of the support along a transversal direction perpendicular to the sliding direction and to the elevation direction, the storage unit further has two respective bevelled lateral walls and, in the storage position, the bevelled lateral walls of the support are parallel to and substantially in contact with the respective bevelled lateral walls of the storage unit.

Therefore, in the storage position, the support is also efficiently maintained relative to the storage unit along the transversal direction.

According to another feature in accordance with the invention, preferably the breathing assembly further comprises a seat and the storage unit is fixed to the seat.

Thus, the pilot can quickly catch the breathing mask in order to don it.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1shows a breathing assembly1comprising a storage unit10, a breathing mask50and a seat2. The seat comprises a seat cushion3, a backrest4and a headrest6. The user of the breathing assembly1, preferably an aircraft crewmember and usually the pilot, is intended to seat on the seat2. As shown in particular inFIG. 2, the storage unit10has a substantially vertical back wall18having holes receiving screws (not represented) maintaining the storage unit10on the top of the backrest4and next to the headrest6.

The storage unit10further comprises a peripheral wall19. The storage unit forms a cup having a receptacle12delimited by the back wall18and the peripheral wall19. The storage unit10has an opening20opposite the back wall18for inserting the breathing mask30into the receptacle12and extracting the breathing mask30from the receptacle12. The peripheral wall19includes a guiding plate14and two bevelled lateral walls16,17.

The guiding plate14is flat, has a substantially constant thickness and extends substantially perpendicularly to an elevation direction Z which is substantially vertical. The guiding plate14has an upper surface13and a lower surface15.

As shown in particular inFIGS. 2 and 5, the storage unit10further has a separate transversal beam30extending in a transversal direction Y perpendicular to the elevation direction Z. The transversal beam30is fixed to the guiding plate14by screws32.

As shown in particular inFIG. 5, two pins21,22are fixed to the transversal beam30. The pins21,22extend along a sliding direction X perpendicular to the transversal direction Y and to the elevation direction Z. Each of the pins21,22comprises a cylindrical retaining portion21a,22atight fitted, and preferably press fitted, into a respective cylindrical bore of the transversal beam30.

As shown in particular inFIG. 5, the peripheral wall19of the storage unit10further has a notch34extending along the elevation direction Z and a protruding portion38which delimits the notch34in the sliding direction X.

It should be noticed that for clarity reasons inFIG. 5only the peripheral wall of the support40is shown and internal channels connecting the supply duct58to the oronasal face piece54are omitted.

The breathing mask50has an oronasal face piece54, an on-demand regulator56and a harness52. The oronasal face piece54is intended to be placed on the face of the user, in communication with the nose and the mouth of the user in order to provide breathing gas for the user. The on-demand regulator56controls the flow of breathing gas provided to the user in accordance with the breath of the user. The on-demand regulator56also controls the concentration in oxygen of the breathing gas provided to the user through the oronasal face piece54. The on-demand regulator56is provided with oxygen from a pressurised source (not represented) through a supply duct58. The breathing mask50could be a full-face mask and therefore include an eye protection. The harness52is intended to press the oronasal face piece54on the user face in order to maintain the oronasal face piece54.

The breathing mask50is intended to be received in the receptacle12of the storage unit10and firmly maintained in a storage position.

The on-demand regulator56includes a rigid casing40and a lever62. The rigid casing forms housing and defines a support40which has a proximal (front) end40aand a distal (back) end40balong the sliding direction X. When the breathing mask50is in the storage position, the proximal end40acan be caught by the user and is therefore outside the receptacle12or near the opening20whereas the distal end40bis at the back of the receptacle12.

The lever62is mounted on the support40proximate the proximal end40aand is movable relative to the support40between a secure state and release state by rotation around a release axis70parallel to the sliding direction X, as shown in particular inFIGS. 6 and 7. The lever62is biased towards the secure state by a spring (not represented). In the release state of the lever62, the harness52is provided with pressurised oxygen from the source, so that the harness52is inflated. In the secure state of the lever62, the harness52is no more in communication with the source of oxygen and consequently deflates, at least partially. This function of the lever is well known and thus will not be described in details.

The oronasal face piece54is rigidly maintained on the support40which is slidingly mounted on the storage unit10between the storage position and an exit position. The breathing mask1, and in particular the support40, slides along the sliding direction X.

The support40has a lower surface39. Between the storage position and the exit position, the lower surface39of the support40rests on the upper surface13of the guiding plate14. Moreover, the support40has an optional retaining element48comprising two transversal wings48a,48bwhich protrude from the lower surface39. The wings of the retaining element48extend through a slot11in the guiding plate40and face the lower surface15of the guiding plate14. Therefore, the retaining element48and the guiding plate14guide the support40in its sliding movement towards the storage position. It should be noticed that the slot11split the guiding plate14, and in particular the upper surface13of the guiding plate14in two portions13a,13b.

Moreover, the support40has two bevelled lateral walls45,46facing and parallel to the respective bevelled lateral walls16,17of the storage unit10and furthermore the retaining element48extends in a substantially rectilinear portion of the slot11of the guiding plate14. The lateral walls45,46extend substantially perpendicularly to the transversal direction Y, but slightly angled so that lateral walls45,46converge one towards the other towards the distal end40bof the support40. So, between the storage position and the exit position, the support40is substantially prevented from translating along the transversal direction Y and from rotation around the elevation direction Z relative to the storage unit10.

Therefore, the breathing mask50, and in particular the support40, is guided in translation along the sliding direction X along a distance D between the storage position and the exit position.

Beyond the exit position, the lower surface39of the support is away from the guiding plate14, so that the support is not slidingly mounted on the storage unit10anymore.

During translation along the sliding direction X of the support40relative to the storage unit10towards the storage position, the bevelled lateral wall45of the support40gets closer to the bevelled lateral wall16of the storage unit10and the bevelled lateral wall46of the support40gets closer to the bevelled lateral wall17of the storage unit10, so translation of support40relative to the storage unit10along the transversal direction Y is progressively restricted. In the storage position, the lateral walls45,46of the support40are substantially in contact with the respective lateral walls16,17of the storage unit10.

At the distal end40b,the support40is close to the transversal beam30and further has a first hole41and a second hole42extending in the sliding the sliding direction X. As shown inFIG. 5, in the storage position, the first pin21of the storage unit10is inserted in the first hole41of the support40and the second pin22of the storage unit10is inserted in the second hole42of the support40.

As further shown inFIG. 5, in the storage position, the first pin21has a first length l21inserted through the hole41and the second pin22has a second length l22inserted through the hole42. The first length l21is preferably between 1 millimeter and 3 millimeters higher than the second length l22. Preferably, the first length l21is about 6 millimeters and the second length l22is about 4 millimeters, and the distance D between the storage position and the exit position is about 40 millimeters.

Each of the first pin21and the second pin22has a cylindrical portion23,26, a conical portion24,27and a tip25,28. Each of the first hole41and the second hole42has a cylindrical portion43,44and a bevelled edge extending in the sliding direction X. In the storage position, the cylindrical portion43of the first hole41surrounds the cylindrical portion23of the first pin21and the cylindrical portion44of the second hole42surrounds the cylindrical portion24of the second pin22.

The cylindrical portion23of the first pin21has a first circular external section S21, the cylindrical portion24of the second pin22has a second circular external section S22, the cylindrical portion43of the first hole41has a first internal section S41and the cylindrical portion44of the second hole42has a second circular internal section S42. The diameter of the first external section S21and the diameter of the second external section S22are preferably close to 3 millimeters. The clearance74between the diameter of the second external section S22and the diameter of the second internal section S42is preferably between 0.01 millimeter and 0.5 millimeter.

The clearance72between the first external section S21and the diameter of the first internal section S41is preferably between 0.01 millimeter and 0.5 millimeter along the elevation direction Z and between 0.5 millimeter and 2 millimeters along the transversal direction. More accurately, the first internal section S41is oblong and elongated along the transversal direction Y. In the elevation direction Z, the first internal section S41is preferably between 0.01 millimeter and 0.5 millimeter greater than the diameter of the first external section S21whereas in the transversal direction Y, the first internal section S41is preferably between 0.5 millimeter and 2 millimeters greater than the diameter of the first external section S21.

However, what is essential is to minimise the portion of the clearance72between the top of the first pin21and the top of the first hole41and the portion of the clearance74between the top of the second pin22and the top of the second hole42, in order to maintain the lower surface39of the support40in contact with the upper surface13of the guiding plate40, at the distal end40bwhen the breathing mask50is in the storage position, even in case of high acceleration/deceleration.

Advantageously, the pins21,22are in metallic material, preferably in steel, and the support40, at least the holes41,42, is in plastic material, preferably in polypropylene.

The breathing mask50is retained in the storage position by a releasable securing device60disposed near the proximal end40aof the support40. The securing device60includes the lever62and the protruding portion38.

As shown inFIGS. 3 and 6, when the lever62is in the secure state, a lateral abutment portion64of the lever62is inserted in the notch34. The lateral abutment portion64of the lever62has a surface extending substantially perpendicularly to the sliding direction X and facing a surface of the protruding portion38of the storage unit10extending substantially perpendicularly to the sliding direction X. Therefore, the support40is prevented from translating relative to the storage unit10along the sliding direction X towards the exit position by abutment of the abutment portion64of the lever62against the protruding portion38of the storage unit10, when the lever62is in the secure state.

The abutment portion64of the lever62has a lateral edge66having a length L66(referenced inFIG. 7) and being substantially vertical in the secure state. The protruding portion38of the storage unit10has a lateral edge36, substantially vertical, having a length L36(referenced inFIG. 7). The length L66of the lateral edge66is preferably about 30 millimeters whereas the length L36of the lateral edge36is preferably about 10 millimeters.

When the lever is in the secure state, the lateral edge66of the lever62is substantially parallel to the lateral edge36of the storage unit10and the distance between the lateral edge66of the lever62and the lateral edge36of the storage unit10is substantially 4 millimeters. So, the surface of contact between the abutment portion64of the lever62and the protruding portion38of the storage unit10is substantially a rectangle having short sides of about 4 millimeters extending along the transversal direction and long sides of 10 millimeters along the elevation direction Z, said rectangle being distant from the release axis70of more than 20 millimeters, preferably substantially 40 millimeters.

As shown in particular inFIGS. 6 and 7, the lever62further as a bottom abutment portion68with extends substantially perpendicularly to the elevation direction Z and, in the secure state, the bottom abutment portion68of the lever faces a bottom abutment surface37of the protrusion38extending substantially perpendicularly to the elevation direction Z. Therefore, when the lever is in the secure state, the lower surface39of the support40is substantially maintained is contact with the upper surface13of the guiding plate, at the proximal end40a,and the support40is prevented from translating relative to the storage unit10along the elevation direction Z.

In the storage position, the breathing mask50is also prevented from translation along the elevation direction Z, from rotation around the sliding direction X and from rotation around the transversal direction Y relative to the storage unit10, because the lower surface39of the support40rests on the upper surface13of the guiding plate.

As shown inFIG. 7, by rotation of the lever62around the release axis70, the lever is moved towards the release state. In the release state, the lateral abutment portion64of the lever62is away from the notch and distant from the protruding portion38of the storage unit10along the transversal direction Y. So, the lateral abutment portion64of the lever62does not face the protruding portion38of the storage unit10anymore along the sliding direction X. Therefore, in the release state, the secure device60does not prevent the breathing mask50from sliding towards the exit position relative to the storage unit10along the sliding direction X.

In the release state, the bottom abutment portion68of the lever62is away from the bottom abutment surface37of the protrusion38along the elevation direction Z.

FIGS. 8 to 10show a second embodiment101of breathing assembly in accordance with the invention. The elements which are identical in the first embodiment and in the second embodiment have their referenced unchanged. The elements of the second embodiment which are different but have a similar or identical function as in the first embodiment have a referenced increased by100.

The breathing assembly101essentially differs from the breathing assembly1in that the support140of the on-demand regulator156of the breathing mask140has two protrusions141,142instead of the holes41,42and the storage cup110has two slots121,122instead of two pins21,22.

Otherwise, the protrusions141,142protrude from the lateral walls45,46along the transversal direction Y, in opposite directions, proximate the distal end140bof the support140.

As shown in particular inFIG. 10, when the breathing mask150is in the storage position, the lower surface139of the support140rests on the two portions113a,113bof the upper surface113of the guiding plate114, the protrusions141,142are received in the slots121,122and the protrusion141,142face respective maintaining surfaces176(only one is represented) of the storage cup110along the elevation direction Z. The maintaining surfaces176delimit the top of the slots121,122. There is preferably a small (non null) clearance174having a thickness e between 0.1 millimeter and 0.5 millimeter above the protrusions141,142, between the protrusions141,142and the respective maintaining surfaces176along the elevation direction Z.

Therefore, the support140is maintained along the elevation direction Z at the distal end140b(with a very low play), even in case of high acceleration/deceleration, the lower surface139of the support being maintained in contact of the upper surface113of the guiding plate114thanks to the protrusion141,142engaging the slots121,122.

As shown in particular inFIG. 9, preferably, when the breathing mask150is in the storage position, there is a small gap between the protrusion141,142and the storage box110along the transversal direction Y.

As shown in particular inFIG. 10, each of the protrusions141,142faces the respective maintaining surface176delimiting the top of the respective slot121,122along a length l121, l122along the sliding direction X. Preferably, said length l121, l122is close to9millimeters. The length l121and the length l122could differ a bit, as the length l21and the length l22of the breathing assembly1.

The lower surface139of the support140slides in contact with the upper surface113of the guiding plate114along a distance D along the sliding direction X, between the storage position and the exit position, preferably close to 40 millimeters.

Moreover, the breathing assembly101comprises two grooves148a,148binstead of the retaining element48of the breathing assembly101, in order to guide the support140from the exit position towards the storage position, the protrusion141,142engaging the grooves148a,148band then engaging the slots121,122.

Finally, the breathing assembly101differs from the breathing assembly1in that it further comprises a rigid bridge109extending along the transversal direction Y and connecting the two portions113a,113bof the upper surface113of the guiding plate114for strengthening the guiding plate114at the proximal end140a. Preferably, the bridge109includes ribs.

As above described, when the breathing mask150is in the storage position and the secure device60is in the secure state, the support140is prevented from sliding along the sliding direction X and from moving away from upper surface113of the guiding plate114along the elevation direction Z at the proximal end140aby abutment of the lever62against the protrusion38.

Of course, the scope of the invention is not limited to the above described embodiment shown for illustrative purpose. For example, the lever62may be slidingly mounted on the support40instead of being rotatively mounted on the support40. In an alternative solution, the release securing device60could for instance comprise an electro-magnet releasably retaining the breathing mask50in the storage position.