Valve for controlled deflation of an airbag cushion

Abstract

The invention relates to a valve for controlled deflation of a cushion (200) of an airbag (300), comprising: a gas path connecting, when installed on the wall of the cushion (200), the inside of the cushion at a gas inlet (35) to the outside at a gas outlet (11), a mechanical actuator (60) in the form of a cord forming a pull-actuator, the actuation of which triggers the passage of gas along the gas path by opening the deflation valve (100), and the release of which closes the gas path and therefore the valve (100), characterized in that it comprises: a piston (40), connected to the mechanical actuator (60) and movable in translation between a closed position, in which it closes the gas path, and an open position, in which the gas path is open, and an elastic element (50) which is loaded for force transmission against the piston (40), applying its elastic force in opposition to the movement of the piston (40) from the closed position to the open position, and preloaded so as to impose a force on the piston which keeps it in the closed position as long as the pressure in the cushion (200) is lower than a maximum pressure, said force being overcome when the cord forming the mechanical actuator (60) is pulled in order to bring the piston into the open position.

Description

[0001] DEFLATION VALVE AIRBAG BAG CONTROL

[0002] Technical field

[0003] The invention relates to the field of airbags or safety pockets in the event of an accident, in particular of the type integrated into an item of clothing such as a vest or a suit for vehicle drivers, skiers or horse riders. The invention relates in particular to the controlled deflation of these airbags, for example to reduce their rigidity and allow the driver to resume his race.

[0004] In the case of a portable airbag, integrated into clothing, it is important that the bladder remains inflated for several seconds to protect the body from secondary impacts and to maintain the body in position in the event of serious injuries. This requires having an airbag with a very good gas-tightness, unlike so-called "open" airbags in vehicles such as cars, where the bladder only remains inflated for a fraction of a second, from a few thousandths to tenths of a second.

[0005] Prior art

[0006] Airbags are known to be integrated into clothing, typically a jacket, vest, or rider's suit, particularly for motorized bicycles such as motorcycles, or in horse riding or ski protection. Clothing incorporating such airbags is particularly intended for athletes and professional riders.

[0007] In sporting events, a driver may suffer a fall that triggers the airbag in his clothing, without his machine being damaged to the point of compromising his continued race.

[0008] For example, in races such as the Paris-Dakar, a motorcycle rider may drive their front wheel into loose sand and fall over their vehicle. The fall they suffer then justifies the deployment of the airbag, but the motorcycle is still in working order. The rider may then wish to resume the race after freeing their vehicle.

[0009] However, airbags are too stiff once inflated to allow the driver to move comfortably, and can compromise the driver's safety by restricting their movement. Notably, most racing regulations and regional and national standards provide for redundancy in airbag vests, allowing the device to be activated twice in succession.

[0010] It would therefore be interesting to be able to implement a valve allowing a driver whose airbag has been triggered to evacuate at least part of the gas that has inflated the bag. This would allow the driver to reduce the stiffness of the airbag until he regains sufficient freedom of movement to allow him to finish the stage or race. In another setting, which can also occur on open roads, the user may find himself on the ground without the possibility of moving. The emergency services then need to deflate the airbag to free the injured person.

[0011] However, this valve must meet several requirements: it must not compromise the pilot's safety, particularly by hindering inflation, and it must not cause any discomfort when the bag is deflated.

[0012] The valve has a potential weak point in terms of sealing, which could compromise the pilot's safety. The valve must also not represent a significant additional cost, and be easily integrated into existing designs.

[0013] The valve must be operable from several directions, in case the pilot does not have easy access to it, or when a rescuer comes to operate it to intervene on the pilot without having to move him too much.

[0014] The valve must not degrade the shock absorption performance of the airbag on impact, by limiting the absorption area too much, or by adding too large a rigid area.

[0015] Furthermore, during a second inflation, gas remaining from the previous inflation can cause overpressure which can on the one hand damage the bladder and on the other hand give excessive stiffness to the airbag once the second inflation has been carried out.

[0016] There is therefore a need for a valve that addresses the above technical problems.

[0017] Brief summary of the invention

[0018] In order to meet this need, the invention proposes a controlled deflation valve for an airbag pocket, comprising:

[0019] - a gas path connecting, when installed on the wall of the pocket, the interior of the safety pocket at its gas inlet to the exterior at its gas outlet,

[0020] - a mechanical actuator in the form of a cord forming a traction actuator, the actuation of which triggers the passage of gas into the gas path by opening the valve, and the release of which closes the gas path and therefore the valve.

[0021] The pilot or rescuer then operates the valve using the actuator. Once enough gas has escaped, they release the actuator, and the valve closes for the next inflation.

[0022] To do this, the valve according to the invention is characterized in that it comprises:

[0023] - a piston, connected to the mechanical actuator, movable between a closed position, in which it closes the gas inlet and an open position, in which the gas inlet is open,

[0024] - an elastic element, forced into force on the piston, opposing its elastic force to the movement of the piston from the closed position to the open position, prestressed so as to impose a force on the piston which keeps it in the closed position as long as the pressure inside the pocket is less than a maximum pressure, and the force of which is overcome when the cord forming the actuator is pulled to bring it into the open position upon actuation. The valve thus obtained allows the airbag pocket to be partially or completely deflated, and also acts as a valve preventing any overpressure in the airbag. It can also be actuated manually, including in the case of an airbag with a single gas generator, for example to allow partial deflation allowing rescuers to handle the injured user.

[0025] The valve according to the invention may further have one or more of the following characteristics.

[0026] The valve may comprise a body in two parts, a lower part, located, in the installed state, inside the safety pocket, and an upper part, located, in the installed state, outside the safety pocket, the two parts pinching, during assembly of the valve, a lip of the wall of the pocket. Said two parts may comprise pre-drilled holes for screws, and be assembled by screwing.

[0027] Alternatively, the two parts can be made of polymer and assembled by welding, in particular by ultrasonic welding.

[0028] The upper part may have a plurality of through holes, forming gas outlets, and a central recess forming a housing for the elastic element, and the piston, and the lower part may have a through bore, forming the gas inlet, and closed, in the absence of actuation, by the piston.

[0029] The valve may include an intermediate insert, into which the gas inlet opens, forming baffles between the gas inlet and the piston to limit the deposition of powders from the combustion of a gas generator at the piston, which may compromise the seal in the closed state.

[0030] At least one of the two parts may have a peripheral recess, into which an annular seal is inserted in compressive support against the wall of the pocket in the installed state.

[0031] The piston advantageously includes a tip which closes the gas inlet in a domed, truncated or conical shape.

[0032] The elastic element may in particular be a helical spring, and the piston may be movable in rectilinear translation between the open and closed positions and guided by shape cooperation in its movement between the open and closed positions.

[0033] Said helical spring is advantageously formed from a metal ribbon corrugated into wavelets with hollows and crests wound in successive turns, the crests of the wavelets of one turn bearing against the hollows of the wavelets of the following turn.

[0034] The invention also relates to a safety garment, comprising an airbag, said airbag comprising: - a pocket forming protection, in the inflated state, for a part of the body of a user,

[0035] - one or more gas generators, configured to inflate the bag when triggered,

[0036] - a control unit, configured to trigger one of the gas generators (301) when a dangerous situation is detected, characterized in that it comprises a controlled deflation valve according to one of the preceding claims, the gas path of which connects the interior of the pocket at its gas inlet to the exterior at its gas outlet.

[0037] Said garment may in particular be produced in the form of a vest or suit, and the deflation valve is advantageously located at the level of the user's collarbone when wearing the safety garment. Brief description of the figures

[0038] The invention will be better understood in light of the description of the figures among which:

[0039] - Figure 1 is a schematic representation of a valve according to one embodiment of the invention in perspective,

[0040] - Figure 2 is a sectional view along a radial plane of the valve of Figure 1,

[0041] - Figure 3 is an exploded view of the valve of Figures 1 and 2, from a front three-quarter view,

[0042] - Figure 4 is an exploded view of the valve of Figures 1 and 2, from a rear three-quarter view,

[0043] - Figure 5 is a schematic representation of an airbag comprising a valve such as in one of the preceding figures,

[0044] - Figure 6 is a schematic representation of a garment incorporating an airbag such as in Figure 5. The figures are given for illustrative purposes and are not limiting. Other embodiments of the invention may be derived from those represented by variations and combinations of features.

[0045] Detailed description of the figures

[0046] Figure 1 is a perspective representation of a valve 100 for the controlled deflation of an airbag pocket according to the invention. The valve 100 is shown in section in Figure 2, and in exploded view respectively from the front three-quarters and rear three-quarters in Figures 3 and 4.

[0047] The valve 100 has a substantially discoid and flattened body. The body of the valve 100 is essentially composed of two parts, also substantially disc-shaped: an upper part 1, having gas outlets 11, and a lower part 3, here composed of two discoid elements, respectively upper 31 and lower 33, and having gas inlets 35. The gas outlets 11 are here produced in the form of holes opening into radial grooves, parallel to the plane of the discoid body of the valve 100.

[0048] The upper 1 and lower 3 parts are assembled here by means of screws 20 inserted into holes. The valve body can be made of metal, in particular steel or aluminum to allow for a long service life and increased strength.

[0049] Alternatively, the upper 1 and lower 3 parts can be made of polymer material, and the assembly can then be done by welding, in particular by ultrasonic welding.

[0050] The upper part 1 is located, in the mounted state of the valve 100, at the outside of the airbag pocket, while the lower part 3 is located, in the mounted state of the valve 100, at the inside of the airbag pocket.

[0051] Figure 2 illustrates this state of affairs. The airbag pocket 200 is here represented by two lips, which are pinched between the upper part 1 and the lower part 3 of the valve 100. In particular, the lower part 3 has a peripheral annular recess in which an O-ring 37 is inserted which reinforces the gas-tightness at the valve 100. The circular shape of the valve 100 makes it possible to avoid a concentration of stresses during inflation which forms on the corners of a polygonal shape, and the flattened nature of the disc makes it possible to prevent the valve 100 from sinking into the inflated pocket and forming a penetrating point which could injure the pilot. However, shapes other than the circular disc are possible: oval, elongated with two semicircles and two straight segments, bean-shaped, etc.

[0052] The radial grooves of the gas outlets 11 prevent an external object, for example the fabric of the garment in which the airbag according to the invention is integrated, from limiting the flow of outgoing gas too significantly.

[0053] The gas inlets 35 are here produced in the form of openings in the radial plane of the valve body 1, and are here in particular four in number. They are located between the discoid elements 31, 33, the lower discoid element 33 having recesses forming said gas inlets 35.

[0054] Other numbers and arrangements of gas inlets 35 are possible.

[0055] Between the gas inlets 35 and the gas outlets 11 there is a gas path, connecting in the installed state of the valve 100, the interior of the bag 200 at the gas inlets 11 to the exterior at the gas outlets 35.

[0056] The gas path is visible in Figure 2, where it is represented by arrows illustrating the path of the gas from the gas inlet 35 on the right in Figure 2 to one of the gas outlets 11 also on the right in Figure 2.

[0057] The gas enters the gas path through the gas inlet 35. It then passes through baffles 39, formed by annular walls nested in staggered rows of the upper 31 and lower 33 discoid elements. These baffles 39 are particularly suitable for pyrotechnic gas generators, as they allow the retention of the majority of particles resulting from combustion when these gas generators are triggered. Indeed, these particles can in particular be deposited on the bearing surfaces of the elements closing the gas path of the valve 100, and thus reduce or even eliminate the sealing thereof in the closed state.

[0058] At the outlet of the baffles 39, the gas arrives at a circular opening which is here closed by a piston 40 having a domed tip so as to come into contact with and close said circular opening, which may alternatively be frustoconical or conical. The piston 40 is movable in translation between a closed position (shown in Figure 2), in which it closes the gas path and an open position, in which the gas path is open.

[0059] Other embodiments may in particular use moving elements such as balls, valves, etc., instead of the piston.

[0060] When the piston 40 is in the open position, the inflation gas passes through the circular opening and then exits through the gas outlets 11 to the outside atmosphere.

[0061] The piston 40 is guided in translation between the closed and open positions by interlocking rail-forming shapes, which ensures a rectilinear translation and prevents the piston 40 from rotating or from getting stuck without closing the gas path. An elastic element 50, here a spring in particular of the helical type, keeps the piston 40 in the closed position in the absence of actuation by a user. The spring 50 is force-loaded on the piston 40. When the airbag inflates, it opposes its elastic force to the movement of the piston 40 from the closed position to the open position. The spring 50 is in particular prestressed so as to impose a predetermined force on the piston which keeps it in the closed position as long as the pressure in the pocket 200 is less than a maximum pressure.

[0062] The valve 100 thus prevents the formation of excess pressure which could either damage the pocket 200 or be uncomfortable or even dangerous for the pilot.

[0063] The spring 50 is in particular housed in a central recess of the upper part 1 of the valve body 100, and is formed of metal ribbons corrugated into wavelets with hollows and crests stacked in successive turns, the crests of the wavelets of one turn bearing against the hollows of the wavelets of the following turn, known in particular from document US4901987. Alternatively, the spring 50 may be a conventional helical spring, or a polymer annular spring in compression.

[0064] The piston 40 is further connected to a mechanical actuator 60, here a cord forming a traction actuator, which exits the valve at its outer face through a central bore 61. The user, either the pilot himself or a rescuer, pulls on said mechanical actuator 60 to overcome the force exerted by the spring 50 and bring the piston 40 into the open position, and thus allow the gas to escape.

[0065] The restoring force exerted by the spring 50, the tensile force of the cord forming the mechanical actuator 60 are in particular aligned, and in particular aligned with the direction of translation of the piston. The force exerted by the pressure of the gas in the pocket is also aligned with these forces and displacements.

[0066] The force exerted by the overpressure is in particular opposed to the return force of the spring 50, their balance maintaining the piston 40 in the closed position. The traction exerted by the user on the cord is in the same direction as the force exerted by the overpressure of the gas, and brings the piston 40 into the open position by overcoming the return force of the spring 50.

[0067] According to yet another variant, actuation by rotation of a button or ring around the valve can form the actuation making it possible to overcome the force exerted by the elastic element 50, by winding the cord during rotation of the button or ring.

[0068] Figure 5 shows an airbag 300 before integration into a safety garment. The airbag is composed of the pocket 200, which is in the form of an enclosure made of woven or non-woven textile material, possibly coated with a layer of silicone or other polymer. The pocket 200 has seams separating its interior volume into elongated tubes, and thus giving the shape once inflated of the airbag 300.

[0069] The bag 200 carries, between two seams of a sausage, the valve 100 previously described, and whose mechanical actuator 60 protrudes. The airbag 300 also comprises in particular two gas generators 301, connected to the bag, and the actuation of which generates the gas allowing the inflation of the bag 200. Other embodiments can of course comprise one or three or even more gas generators 301.

[0070] The gas generators 301 are electronically connected to a control unit UC which triggers said gas generators when a dangerous situation is detected.

[0071] The pocket 200 here has a neck-forming recess 201 and two holes 203 for the user's arms to pass through. It is thus suitable for integration into a vest or suit-type garment, and is configured to protect the user's torso during inflation.

[0072] Figure 6 shows said garment 400, made in the form of a vest worn around the torso of the user U, of which only the bust is visible. The mechanical actuator 60 protrudes outside the garment 400, at the level of the clavicle of the user U, where the valve 100 is also arranged.

[0073] The actuator 60 terminates in a strap which, for example, bears a brightly colored marking indicating pull to deflate, and which is, for example, removably attached to the fabric of the garment 400, for example by textile hook and loop fastener or fusible stitching.

[0074] By being arranged at the level of the clavicle, the valve 100 and the actuator 60 are particularly accessible for the U pilot or a rescuer working on the U pilot. Another valve 100 with an actuator 60 can also be arranged in the back of the U pilot to allow deflation by a rescuer in the case of an unconscious U pilot lying on his stomach or whose clavicle and the first valve 100 are inaccessible.

[0075] The particular design of the valve 100 according to the invention makes it possible to greatly reduce its dimensions, so that it can be integrated into a pocket 200 of an airbag 300 of conventional construction between the seams of a sausage. Its small size and its flat character ensure that it does not represent a weak point in terms of safety and risk of rupture of the pocket 200 upon inflation.

[0076] The translational guidance of the piston 40, the domed or convex shape of said piston 40, the baffles 39 and the presence of a tubular or helical metal spring 50, in particular, make it possible to ensure safe reuse over a large number of inflation-deflation cycles. The user U can thus keep his bag 200 with the valve 100 for a long time and only needs to replace the gas generators in the event of a trigger.

Claims

CLAIMS 1. Controlled deflation valve for a pocket (200) of an airbag (300) comprising: - a gas path connecting, in the state installed on the wall of the pocket (200), the interior of the pocket at a gas inlet (35) to the exterior at a gas outlet (11), - a mechanical actuator (60) in the form of a cord forming a traction actuator, the actuation of which triggers the passage of gas into the gas path by opening the deflation valve (100), and the release of which closes the gas path and therefore the valve (100), characterized in that it comprises: - a piston (40), connected to the mechanical actuator (60), movable in translation between a closed position, in which it closes the gas path and an open position, in which the gas path is open, - an elastic element (50), forced into force on the piston (40), opposing its elastic force to the movement from the closed position to the open position of the piston (40), prestressed so as to impose a force on the piston which keeps it in the closed position as long as the pressure in the pocket (200) is less than a maximum pressure, said force being overcome when the cord forming the mechanical actuator (60) is pulled to bring it into the open position.

2. Valve according to claim 1, characterized in that it comprises a body in two parts, a lower part (3), located, in the installed state, inside the pocket (200), and an upper part (1), located, in the installed state, outside the pocket (200), the two parts (1, 3) pinching, during assembly of the valve, a lip of the wall of the pocket (200).

3. Valve according to claim 2, characterized in that the two parts (1, 3) have pre-drilled holes for screws (20), and are assembled by screwing.

4. Valve according to claim 2, characterized in that the two parts (1, 3) are made of polymer and assembled by welding.

5. Valve according to claim 2, 3 or 4, characterized in that the upper part has a plurality of radial grooves, forming gas outlets (11), communicating with a central recess forming a housing for the elastic element (50) and the piston (40), and in that the lower part (3) has an opening closed, in the absence of actuation, by the piston (40).

6. Valve according to one of claims 2 to 5, characterized in that it comprises baffles (39) between the gas inlet (35) and the piston (40).

7. Valve according to one of claims 2 to 6, characterized in that at least one of the two parts (1, 3) has a peripheral recess, in which an annular seal (37) is inserted in compressive support against the wall of the pocket (200) in the installed state.

8. Valve according to one of the preceding claims, characterized in that the piston (40) comprises a tip closing the gas path of domed, truncated or conical shape.

9. Valve according to one of the preceding claims, characterized in that the elastic element (50) is a helical spring, and in that the piston (40) is movable in rectilinear translation between the open and closed positions and is guided by shape cooperation in its movement.

10. Safety clothing (400), comprising an airbag (300), the airbag (300) comprising: - a pocket (200) forming protection, in the inflated state, for a part of the body of a user (U), - one or more gas generators (301), configured to inflate the pocket (200) when triggered, - a control unit (UC), configured to trigger one of the gas generators (301) when a dangerous situation is detected, characterized in that it comprises a controlled deflation valve (100) according to one of the preceding claims, the gas path of which connects the interior of the pocket (200) at its gas inlet (35) to the exterior at its gas outlet (11).

11. Clothing according to the preceding claim, characterized in that it is produced in the form of a vest or suit, and in that the valve (100) is located at the level of the user's clavicle (U) when he wears the safety clothing (400).

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