Protective headgear equipment with respirator and optical shield

A head protective equipment comprises: —a breathing mask (2) connectable to a breathing-gas source and adapted to be applied, in a use position, around an user's nose and mouth, for supplying said user with breathing gas; —a shield (6) adapted to be applied around the user's eyes; and—first and second lock elements (28, 30, 38, 40), respectively located on said mask and on said shield, and adapted to cooperate with each other in order to secure said shield to said mask when said mask is in said use position around said user's nose and mouth, said first and second elements being adapted to create a snap-together connection, —said shield and said mask being adapted to be locked together by a two-step movement, the first step consisting in approaching the shield to the mask until said shield reaches said mask, and the second step being a substantially linear movement until locking.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the U.S. national phase of International Application No. PCT/IB2007/000581 filed on Jan. 19, 2007 and published in English on Jul. 24, 2008 as International Publication No. WO 2008/087468 A1, the entire contents of which are incorporated herein in their entirety by reference.

The invention relates to a protective equipment for the head, with a breathing mask and an optical shield.

More particularly, the invention relates to protective equipment for the head comprising:a breathing mask that can be connected to a breathing-gas source and adapted to be applied, in a position of use, around the nose and the mouth of a user, and for supplying him/her with breathing gas,a eye protective shield adapted to be applied around his/her eyes, andfirst and second lock elements, respectively located on the mask and on the shield and adapted to cooperate with each other in order to secure the shield to the mask when the mask is in its position of use on the user's face.

The invention has a particularly important, though not exclusive, application in aeronautics. The mask then makes it possible to combat hypoxia or the inhalation of toxic gases. Regulations may also demand that pilots and co-pilots of transport aircraft wear equipment for protection against hypoxia permanently in certain flight conditions, and particularly at very high altitude or when a single pilot is present in the cockpit.

During this period, the mask is worn without a shield. However in case of fire or in presence of smoke or irritating gases, the wearer needs to add easily and quickly a shield to protect his eyes while he keeps the mask on his face.

Document U.S. Patent Application No. 2005/0210556 discloses an example of such protective equipment that is entirely satisfactory in term of protection. However, it could be advantageous to have such equipment in which the positioning of the shield on the mask as well as the unlocking of the shield from the mask, in particular when the mask is already in place on the user's face, is carried out even more simply and more naturally.

To better address one or more concerns, in a first aspect of the invention, a head protective equipment comprises:a breathing mask connectable to a breathing-gas source and adapted to be applied, in a use position, around the user's nose and mouth, for supplying the user with breathing gas;a eye protective shield adapted to be applied around the user's eyes; andfirst and second lock elements, respectively located on the mask and on the shield, and adapted to cooperate with each other in order to secure the shield to the mask when the mask is in the use position on the user's face. The first and second elements are adapted to engage and interlock with each other to create a snap-together connection.

The shield and the mask are adapted to be locked together by a two-step movement, the first step consisting in approaching the shield to the mask until the shield reaches the mask, and the second step being a substantially linear movement of bringing the shield closer to the user's nose until locking.

The head protective equipment has the advantage to put in place the shield by a natural movement of the user.

In a particular embodiment, the shield comprises a grasping unit around the second lock element. The grasping unit comprises two substantially vertical surfaces and one substantially horizontal surface, the surfaces being adapted to receive the user's fingers during the positioning of the shield onto the mask. Particularly, the vertical surfaces are adapted to receive the user's thumb and middle finger and the horizontal surface is adapted to receive the user's forefinger. The embodiment has the advantage to offer a natural position of the user's fingers to grasp the shield.

In another embodiment, the mask has guidance elements to guide the shield to the locking position during the substantially linear movement. The guidance elements comprise a support area adapted to receive the shield at the end of the first step movement. They comprises also guidance surfaces diverging from a ridge situated substantially in coincidence with the user's nose bridge, and forming two wings that are substantially symmetrical with respect to a median plane of symmetry of the user's face when the equipment is being worn by the user. The wings are substantially parallel to the linear movement. This embodiment has the advantage to guide the user in the positioning of the shield onto the mask.

An other aspect of the invention is a method to lock a eye protective shield onto a breathing mask. The breathing mask is connectable to a breathing-gas source and adapted to be applied, in a use position, around an user's nose and mouth, for supplying the user with breathing gas. The eye protective shield is adapted to be applied around the user's eyes. The mask and the shield are lockable by first and second lock elements, respectively located on the mask and on the shield, and adapted to cooperate with each other in order to secure the shield to the mask when the mask is in the use position around the user's nose and mouth. The first and second elements are adapted to engage and interlock with each other to create a snap-together connection. The method comprises:approaching the shield to the mask until the shield reaches the mask,moving in a substantially linear movement the shield onto the mask to bring the shield closer to the user's nose until locking.

In the following description, like reference numerals will be used to refer to like or corresponding elements in the different figures of the drawings. Position terms such as “top”, “bottom”, etc. are used to define relative position of elements of a protective equipment when it is worn by a user.

The mask2and the harness4are of a known type. They are for example of the type of those already described by the documents EP-A-0288391 or U.S. Pat. No. 5,630,412.

The mask2comprises a mouth-and-nose face cover8, a demand regulator10, a connecting unit12and a shell14. The demand regulator10is connected to a source of pressurized breathing gas by a flexible tube16. The connecting unit12connects the demand regulator10to the inflatable harness4through a harness block17. The shell14covers the front of the mouth-and-nose face cover8.

The harness is fitted with straps18to maintain the mask2in use position on user's head. On each side of the mask2, a positioning member20positions the harness outside the area of the user's face covered by the shield6in use position. In another aspect, positioning members20are adapted to guide the harness around the head of the user even when the harness is not inflated. Therefore, the user can put in place the mask around his/her nose and mouth by using a single hand.

As shown inFIG. 2andFIG. 3, the mouth-and-nose face cover8is adapted to be applied over the bottom of a user's face. The mouth-and-nose face cover8comprises a cavity covering the nose and the mouth of the user. This cavity is lined with a flexible membrane also extending all around the latter in order to form a seal22intended to be applied in contact with the user's face.

The shell14comprises a ridge surface24located substantially in coincidence with that of the user's nose when the user is wearing the mask2. The shell14is substantially symmetric with respect to a median plane P corresponding to the plane of symmetry of the user's head. It comprises, on each side of the median plane P, two guidance surfaces26, forming a groove having a funnel form starting from the ridge surface24. The two grooves define a translation axe XX substantially perpendicular to the ridge surface24.

On the ridge surface24, above the start of the guidance surfaces26, a substantially plane surface28is perpendicular to the translation axe XX. The plane surface28comprises an opening30having a rectangular shape. The opening30is horizontally-oriented.

The shield6comprises a protection glass32and, beneath the protection glass32, a grasping unit34.

The grasping unit34comprises two substantially vertical grasping surfaces36and a substantially horizontal grasping unit37. The grasping surfaces36have an ergonomic shape adapted to receive the user's fingers and particularly the user's thumb and middle finger for the vertical surfaces36and the forefinger for the horizontal surface37.

Inside the grasping unit34,FIG. 4andFIG. 5, between the two grasping surfaces36, two flexible pins38are attached by their proximal ends to the grasping unit34and form at their distal ends a hook40turned outwards. Each hook40has a substantially triangular shape.

The two pins38form a substantially horizontal plane.

Under the two pins38, two convex parts44have a form adapted to be placed between the guidance surfaces26of the mask.

The operation of the head protective equipment is the following.

The user has already the mask2in place on his mouth and nose. The mask is kept on the user's face by the harness4.

The user takes the shield6by pinching the grasping unit between the user's thumb and middle finger onto the vertical grasping surfaces36. The forefinger is placed onto the horizontal grasping surface37. The finger position is natural and helps to position correctly the shield in space.

In a first movement, similar to the natural movement consisting to touch the nose with the finger, the user approaches the shield to the mask until the shield reaches the mask.

The harness block17, the positioning members20as well as the part of the harness between the harness block and the positioning members act as a support element which receives the shield at the end of this first movement.

Then, in a linear movement guided by the support element along the axis XX, the user brings the shield6closer to the mask2until the convex parts44arrive at the level of the guidance surfaces26. Then, the movement is guided by the guidance surfaces26in which the convex parts44are inserted. As the guidance surfaces have a funnel-type form, the movement is increasingly guided and precise in the positioning of the shield vis-à-vis the mask. With the guided movement, the distal ends of the pins38arrive at the level of the opening30. The size of the opening30is such that the external sides of each hook40slide along the side of the opening30and elastically move inwards the pins38. The linear movement continues until the hooks pass through the opening30and the pins38return to their initial position.

Then, the pins38and the opening30create a snap-together connection locking the shield6to the mask2.

To unlock the shield6from the mask2, the user holds the shield by the grasping surfaces26,27as described here above and pulls the shield to break apart the mask and the shield. As the hooks40form an obtuse angle with the respective pins and the pins have elasticity of flexure, the pins38bend inwards until the hooks40withdraw from the sides of the opening30. The user is then free to take away the shield6from the mask2.

The man skilled in the art understands that the choice of the obtuse angle and of the elasticity of flexure of the pins has an impact on the stability of the locking mechanism, particularly on the stability of the locking position and on the needed strength to unlock the shield.

The described locking mechanism has the advantage to put in place, or to take out, the shield by a natural movement of the user.

While the invention has been illustrated and described in details in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiment.

For instance, the guidance elements may have different forms such as, for instance, a two-teeth fork adapted to be inserted into two funnel-type holes.