Abstract:
A device for fastening ( 1 ) fastens an accessory ( 2 ) such as an oxygen mask on a helmet ( 3 ). A main assembly (MP) arranged on the helmet co-operates with a complementary assembly (MC) integral with the accessory ( 2 ). A safety device unfastens the accessory when it is in contact with a liquid. The safety device comprises at least an element ( 4 ) designed to trigger unlocking of the main and complementary assemblies (MP, MC) by the action of an electromechanical unlocking mechanism.

Description:
BACKGROUND  
       [0001]     The present invention relates to the systems that fasten accessories on a helmet and more exactly a security device designed to allow the removal or automatic unhooking of the accessory in certain situations.  
         [0002]     Knowing that many types of masks previously designed to equip professionals like firemen, soldiers or pilots and others used for leisure like mountaineering, spelunking or motorcycling, for example. These masks, specific to their use, sometimes use accessories which attach to the helmet, such as oxygen masks, gas masks, devices of communication or others. However, in certain urgent situations, these accessories attached to the mask can be trouble and even cause problems.  
         [0003]     This is, for example, the case when a airplane pilot ejects from his plane and he is in an aquatic environment, the presence of his oxygen mask can cause serious harm to the pilot who has to manually manipulate the aforesaid fastener to get it off, manual operation which can prove to be delicate and which the pilot is not inevitably in a position to carry out.  
         [0004]     Thus, to remedy this particular case and allow the release of the oxygen mask or gas mask during this type of incident, a device which allows the automatic release of the oxygen mask when the mask touches water had to be imagined.  
         [0005]     The revealed device is thus known by the American patent U.S. Pat. No. 4,869,245, which is a device including an explosive charge, the explosion destroys the part that attaches to the mask and thus provides its release. Very well understanding that this device is not satisfactory. In fact, the explosion could injure the user. Also, the applicant already proposes another device, according to which, the unlocking element is not an explosive charge, but is formed by a pill-like element in a material which deteriorates very fast in a humid environment, this also provides the release of the mask. This last solution is already perfected, but it is not totally satisfactory, because it is difficult to implement reliably.  
         [0006]     The present invention thus has the objective to solve the precise problems with simple means, reliable and easy to implement, which allows among other things a periodic test which is controlled and non-destructive.  
       SUMMARY  
       [0007]     For this purpose, it relates to a device attaching accessories such as an oxygen mask on a helmet. A type of the principal assembly system is laid out on the helmet to cooperate with a complementary assembly system on the accessory.A security device provides the unhooking of the accessory when it finds itself in contact with a liquid.The security device is realized without a release or unlocking element, the aforementioned system, acting by means of unlocking electro mechanics.  
         [0008]     Advantageously, the means of the unlocking electro mechanics include an electric motor, controlled by the release element, and acting on the unlocking pieces in order to assure the release of the locking pieces of the helmet which cooperate with the part that attaches the accessory.  
         [0009]     Other characteristic and advantages of the invention will be revealed by the description which will follow in the attached drawings which were only given as non-restrictive examples. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIGS. 1 through 10  illustrate the preferred and alternate embodiments of the attaching device and of the associated helmet.  
         [0011]      FIG. 1  is a perspective view of a pilot&#39;s helmet and its oxygen mask attached by an attaching device in accordance with the invention.  
         [0012]      FIG. 2  is a picture of a pilot&#39;s helmet and its mask when it has been detached thanks to the security device.  
         [0013]      FIG. 3  illustrates a principle clasp assembly in an exploded view.  
         [0014]      FIG. 4  illustrates a longitudinal section of the principle clasp and a complementary device.  
         [0015]      FIG. 5  is a view from below the case.  
         [0016]      FIG. 6  and  7  are schematic representations of the functioning security device, respectively, in an assembled position ( FIG. 6 ) and during the ejection of the jaws and in a final position once it has been detached ( FIG. 7 ).  
         [0017]      FIGS. 8, 9 , and  10  show the attaching clasp in perspective, respectively in the locked position ( FIG. 8 ), in the process of unlocking ( FIG. 9 ) and unlocked ( FIG. 10 ).  
         [0018]      FIG. 11  is a circuit diagram of the electronic system.  
         [0019]      FIG. 12  is a perspective view of the electronic circuit with its protective envelope, both electrodes make the sensor which detects the presence of water.  
         [0020]      FIG. 13  is a perspective view from below the removable case of the release element. 
     
    
     DETAILED DESCRIPTION  
       [0021]     According to the invention, an attaching device  1  of an accessory  2  on a helmet  3  is a type comprising of a principle assembly system (MP) laid out on the helmet  3  designed to cooperate with a complementary assembly system (MC) joined to the accessory.  
         [0022]      FIGS. 1 and 2  show, the attaching device in an exemplary application for attaching oxygen masks  2  on the helmet  3  of airplane pilots. However, it could also be used for other accessories likely to be a problem for the pilot when he ejects from the cockpit of his airplane and finds himself in the sea, for example, or to be used in other applications related to different types of masks.  
         [0023]     The attaching device  1  includes a security device which provides the unlocking of the accessory  2  when it finds itself in contact with liquid. This security device is an electro mechanic type and includes at least an element of unlocking release  4  which, when it is in contact with liquid such as water, provide the disassembly of the principle assembly system (MP) and the complementary assembly system (MC). The aforementioned unlocking release element is accomplished by an immersion sensor connected to an electric circuit  12  housed in a case with an electronic motor  13 , whose function will be explained below in the description.  
         [0024]     In addition, the security device includes a means of unlocking, activated by an unlocking release element  4 , that is to say by the electronic circuit, when this last is in contact with water.  
         [0025]     Let us note that the unlocking element  4  as well as the unlocking system are advantageously placed in the attaching device  1 , which includes a base plate  5  designed to be fixed to helmet  3 , and more precisely on one side , such as  FIG. 2  illustrates, while this plate  5  is connected in a releasable way to a removable case  6  designed to be released from its attachment with the base plate  5  when the device is in contact with water.  
         [0026]     To do this, the attaching device  1  has locking pieces  7   a ,  7   b  joined to the helmet which cooperate with fixing elements  8   a ,  8   b  in connection with the accessories on the mask  2 , in order to fix the principal assembly system (MP) with the complementary assembly system (MC), this co-operation can only be carried out when the aforementioned locking pieces  7   a ,  7   b  are positioned in the assembly position (A), a position in which they are maintained by the security device as long as it is not released by contact with water.  
         [0027]     According to the preferred use , the locking pieces  7   a ,  7   b  and the security system which are held in the assembly position (A) are placed on the principal assembly system (MP), that is to say on the helmet  3 , while the fixing elements  8   a ,  8   b  are carried by an attaching buckle  9  connected to the attaching strap  10  of the mask. These attaching elements  8   a ,  8   b  are formed by two movable locking teeth that resist against removal by means of resilient bias. It goes without saying that the configuration of the fixing device could be different and that the security device with its locking pieces and its unlocking elements could be laid out, either on the principle assembly system (MP) of the helmet  3 , or directly on the complementary assembly system (MC) carried by the accessory  2 , without leaving the field of protection of the invention.  
         [0028]     The base plate  5  advantageously carries the locking pieces  7   a ,  7   b  which are formed by two toothed jaws positioned in the base plate  5  to allow the attaching buckle to pass through and for its teeth  8   a ,  8   b  to lock with their respective teeth in order to obtain cooperation between the aforementioned teeth and the teeth of the jaws, as it shows more precisely in the  FIG. 4 .  
         [0029]     The aforementioned cooperation can be stopped thanks to a manual unlocking device  11  with a classic type of pushbuttons which can be carried by the complementary assembly system (MC) and which allow the locking teeth  8   a ,  8   b  to retract, for example, maybe the release of the security device which move the locking pieces  7   a ,  7   b  to make them leave the assembled position (A) in which the cooperation with the teeth  8   a ,  8   b  is possible, such as illustrated by  FIGS. 4 and 6 .  
         [0030]     According to the preferred use of the principle system, the security device is made up of a resilient biasing device  14   a ,  14   b ,  14   c ,  14   d  designed to bias the locking pieces  7   a ,  7   b  to urge them to leave the assembled position (A) and the stop which maintains the locking pieces in the assembled position (A) against the action of the resilient biasing device. The aforementioned stop means is made by the removable case  6 , controlled by the unlocking system which allows, when the immersion sensor  4  is in contact with a liquid, the release of the aforementioned stop means and thus the locking pieces leave their assembled position under the action of the resilient biasing device  14   a ,  14   b ,  14   c ,  14   d.    
         [0031]     The resilient biasing device is advantageously made up by four springs  14   a ,  14   b ,  14   c ,  14   d  which are designed to be positioned in the box  15  of the locking pieces taking support on the bottom  16  of the base plate  5 . They are compressed when the locking pieces  7   a ,  7   b  are in the assembled position (A).  
         [0032]     The stop means whose release is controlled by the unlocking element  4 , but implemented by the unlocking system, formed by the movable release case  6  fixed and retained on the base plate  5  in a manner to prevent the movement of the locking pieces  7   a ,  7   b  when they are in the assembled position (A).  
         [0033]     The unlocking means is placed in the removable case  6 , are made by two actuation rods  17   a ,  17   b , moved in translation by a mobile carriage  18  in translation and an electric motor  13  driving a central threaded shaft  20 .  
         [0034]     Each of the rods is mounted swiveling on the level of their central part, in the removable case around their pivot axis, respectively  21   a ,  21   b , to define on one side of the axis, an external arm, and on the other side an internal arm extending towards the general axis from the case. In addition, the end of each of the internal arms is connected to a central axle  22  close to the mobile carriage, the carriage being mounted in translation on the central threaded shaft  20 .  
         [0035]     It was understood that the rotation of the aforementioned central threaded shaft, by the motor  13 , provides the longitudinal displacement of the carriage  18  which swivels the two rods  17   a ,  17   b.    
         [0036]     In the assembled position (A), such as is illustrated in  FIGS. 1, 6 ,  8 , the removable case  6  is retained on the base plate  5 , thanks to the cooperation of several lateral locking hooks  23   a ,  23 ′ a ,  23   b ,  23 ′ b ,  24   a ,  24 ′ a ,  24   b ,  24 ′ b . While supplying the electric current of the motor  13  the threaded shaft  20 , is rotated on its axis, and thus moves the carriage towards the front according to (F 1 ), which causes the rods to swivel according to (R). Given that the ends  25   a  ,  25   b  of each of the external arms of the rods  17   a ,  17   b  are inserted in the hollow support recesses  26   a ,  26   b  placed in the lateral sides of the base plate, the pivoting of the rods provides translational displacement of the case towards the front according to (F 2 ) compared to the base plate, such as is illustrated in  FIG. 9 . This displacement thus makes it so that the cooperation of the locking side hooks ceases, and it is the release of the case, such as is illustrated in  FIGS. 2, 7 , and  10 .  
         [0037]     While going from the locked position to the unlocked position, the stop means (MB) or the case  6  is ejected from the base plate, under the impulse of the resilient biasing device  14   a ,  14   b ,  14   c ,  14   d  at the same time the locking pieces  7   a ,  7   b  are, as  FIGS. 2, 3 , and  7  show it. The ejections of the stop means (MB) and the locking pieces  7   a ,  7   b  are carried out towards the outside of the base plate  5  without any trouble, thanks to the particular construction of the stop means, which allows it to play the role of the ejectable part, on the one hand, and in addition owing to the fact that the springs  14   a ,  14   b ,  14   c ,  14   d  are connected to their corresponding locking pieces. It will also be noted that the base plate, in the zone occupied by the fixing elements of the mask does not include a side wall. This construction allows a base plate  5  whose form leaves thus the locking pieces are ejected upwards, while leaving a free trajectory for the part carrying the locking pieces of the mask.  
         [0038]     One can note that the base plate  5  is advantageously fixed to the helmet by a pivot  28 , allowing the base plate  5  to take the best angular position by swiveling.  
         [0039]     In addition, it will be noted that the case has the form of a protecting hood designed to preserve an unquestionable aestheticism to the helmet, the aforementioned hood being obviously non-tight to allow water to touch the unlocking element.  
         [0040]     The unlocking release element in made up by an immersion sensor  4 , connected to an electric circuit  12  designed to power the actuating motor  13  to operate the unlocking system.  FIG. 11  is a schematic diagram of the electronic system.  
         [0041]     The electronic system includes an immersion sensor  4  whose role is to measure the conductivity of the water when it is immersed, the aforementioned sensor being connected to a transistor. The electronic circuit  12  includes: an integrator  31 , a power supply switch control  32 , an electronic switch  33 , a microcontroller  34 , an optocouplor  35 , and a comparator  36 .  
         [0042]     The immersion sensor  4  is made up by two electrodes  40 ,  41  connected to a transistor.  
         [0043]     Let us also note that the device includes an electric current supply  30 , such as a flat battery.  
         [0044]      FIG. 12  is a perspective view of the electronic circuit with its protective case, whose two electrodes  40 ,  41  jut out forming the water sensor  4 . The two electrodes  40 ,  41  are advantageously connected to an enameled copper wire, having a diameter of 0.7 millimeters. Let us note, like it appears in  FIG. 13 , the two electrodes  40 ,  41  jut out of the removable case  6 . Let us add that the aforementioned case  6  is advantageously watertight and includes the electronic circuit  12 , the battery  30  and the motor  13  with its transmission elements  18 ,  20 .  
         [0045]     It goes without saying that one could envision other water sensor systems like for example by a sonar system, ultra sound, or electromagnetic pulse.  
         [0046]     As is known, the invention is not limited by the embodiments described and represented by the titled examples, but it may also include all the equivalent techniques and thus their combinations.