Patent Publication Number: US-2007103891-A1

Title: Device for fixing a detachable lamp to a crash helmet

Description:
The present invention relates to a fixing device for holding a removable lamp on a protective helmet.  
      The invention is particularly advantageous, but not limited to, firemen&#39;s helmets.  
      In a certain number of applications, it can be important to attach in a nonpermanent way a removable lamp on an external surface of a protection helmet. Many users of this type of helmet regularly work in situations with little or no light. One thinks of firemen or soldiers, but also of construction workers, miners or speleologists.  
      To make a helmet usable with a removable lamp, the device needs a fixing device made up of a support element and an catching element. The support element is attached on one side of the helmet, while the catching element includes a sleeve to receive the lamp. In order to give the lamp its removable characteristic, the sleeve has a projecting member that is adapted to engage a horizontal guide slot of the support element. The engagement of this projecting member is carried out horizontally from back to front; the sliding movement of the catching element is only blocked towards the front.  
      However, this type of fixing device presents the disadvantage of not inhibiting sliding movement toward the rear such that the catching element can be caused very easily to disengage form the guide slot, in particular following an impact between the lamp and a foreign object. This is detrimental to the material itself, since the lamp can be damaged at the time of its fall, but also for the user who finds himself then without this means of personal lighting.  
      Additionally, the technical problem solved by the object of this invention, is to propose an attachment intended to keep a removable lamp on a helmet, the fixing device comprising a support element intended to be attached to a helmet and a catching element intended to be attached to the removable lamp, the catching element being adapted to slide in the guide rails disposed on the support element, the sliding of the catching element being blocked at one end of the guide means by the first blocking means, this fixing device which makes it possible to avoid problems by guaranteeing that the removable lamp will stay attached in the event of an impact, when the aforementioned impact is appreciably collinear with the direction of the sliding motion of the catching element in the support element.  
      The solution of the proposed technical problem is, according to the present invention, to have the fixing device comprise a second blocking means to block the sliding motion of the catching element at the other end of the guide means, and in which the catching element is adapted to be inserted in the guide means following a direction appreciably perpendicular to the direction of the sliding motion of the aforesaid catching element in the aforementioned guide means.  
      It is significant that the catching element is able to slide in the guide means between two extreme positions which are limited respectively by the first and second stops. In a particularly advantageous way, the catching element cannot be disengaged at the time of its sliding motion in the guide means, contrary to its counterpart.  
      As the insertion of the catching element in the guide means is carried out in a direction substantially perpendicular to the direction of the sliding motion of the aforesaid catching element at the aforementioned guide means, the withdrawal of the removable lamp requires a movement much more complex than before. This movement breaks up into a first movement along the direction of the sliding motion, combined with a second movement perpendicular to the first and along the direction of insertion.  
      The invention, as is presently defined, thus presents the advantage of guaranteeing the maintenance of the removable lamp, in the event of an impact along a direction substantially collinear with the sliding motion direction. The disengagement of the lamp can be carried out only at the will of its user, after a sufficiently complex manipulation to prevent any accidental dissociation. The fixing device according to the invention thus constitutes a true safety system.  
      The present invention relates equally to the characteristics which will arise during the description which will follow, and which will be considered separately or to all their possible technical combinations. 
    
    
      Other characteristics and advantages of the invention will emerge from the description which will follow as well as the annexed drawings which are given only by way of nonrestrictive examples.  
       FIG. 1  is a side view illustrating a protective helmet on which a removable lamp is removably mounted by a fixing device according to the invention.  
       FIG. 2  shows the removable lamp of  FIG. 1  in frontal perspective, the catching element being directly integrated into the body of the aforementioned removable lamp.  
       FIG. 3  shows a side view of the lamp in  FIG. 2 .  
       FIG. 4  is a rear perspective view of the support element forming part of the fixing device of  FIG. 1 .  
       FIG. 5  constitutes a frontal perspective view of the support element in  FIG. 4 .  
       FIG. 6  is a cross-section illustrating diagrammatically the co-operation between the catching element and the support element composing the fixing device of  FIG. 1 .  
       FIG. 7  is a cross-section representing diagrammatically the means of indexing partially visible in FIGS.  2  to  5 . 
    
    
      For reasons of clarity, like elements have been designated by identical reference numbers. Only the essential elements for the comprehension of the invention have been represented, and this without respect to scale and in a diagrammatic way.  
       FIG. 1  illustrates a fixing device  1  making it possible to maintain a removable lamp  2  on a protective helmet  3  of a fireman.  
      In this particular embodiment chosen only by way of example, the fixing device  1  is composed of a support element  4  attached on the side of the helmet  3 , as well as a catching element  5  attached to the removable lamp  2 . The catching element  5  is slidably mounted in horizontal guide means  10  on the support element  4 ; the sliding motion of the catching element  5  being blocked to the front by first stop  20 .  
      In accordance with the object of this invention, the fixing device  1  comprises moreover a second stop  30  adapted to block any sliding motion towards the back of the catching element  5  in the guide means  10 . Moreover, the catching element  5  is adapted to be inserted in the guide means  10  near the second stop  30 , along a direction substantially perpendicular to the direction of sliding motion of the aforesaid catching element  5  in the aforementioned guide means  10 .  
      As one can see in  FIGS. 2 and 3 , the catching element  5  is an integral part of the structure of the removable lamp  2 . But, of course, one could envision an alternative in which the catching element  5  would include a sleeve able to temporarily receive the body of the removable lamp  2 . In any event, the catching element  5  comprises a projecting member  6  at a free end  7  which is arranged orthogonally a shoulder  8  forming a shoe.  
      As  FIGS. 4 and 5  show, the guide means  10  comprised of two parallel grooves  11   a ,  11   b  arranged horizontally in the support element  4 , and on both sides of the direction of sliding motion of the catching element  5 . The unit is arranged so that each guide slot  11   a ,  11   b  can cooperate with the sliding motion in at least a portion of the shoulder  8  of the catching element  5 , in accordance with  FIG. 6 .  
      According to a characteristic of the invention, the catching element  5  is adapted to pivot at least partially on the guide means  10 , along an orthogonal axis to the direction of sliding motion. In practice, the shoulder  8  in a circular form is able to slide longitudinally and to pivot orthogonally in the guide slots  11   a ,  11   b . This is visible in  FIGS. 2 and 3 , which allow modification of the orientation of the lamp  2  relative to the helmet  3  along a vertical plane.  
      It can be advantageous to be able to gradually modify the inclination of the lamp  2 , but also has to be able to benefit from a true immobilization of the aforementioned lamp in each position. According to another characteristic of the invention, the fixing device  1  comprises means of indexing  40  able to immobilize the pivoting of the catching element  5  along the guide means  10 , in at least two predetermined inclinations with respect to the direction of the sliding motion.  
      In this embodiment, the means of indexing  40  comprises of a projecting element  41  and three embossings  42  respectively attached to the catching element  5  and the support element  4 . In accordance with  FIG. 7 , the projecting element  41  is adapted to cooperate, on the one hand, by sliding over the free end  43  of each embossing  42 , and in addition, by partially blocking the base  44  of each embossing  42 . The displacement of the projecting element  41  by yielding to the embossings  42  is allowed by the play between the catching element  5  and the support element  4 , and possibly by a certain elastic deformation of the unit. Of course, an alternative with at least one embossing  42  interdependent of the catching element  5  and at least one projecting element  41  attached to the support element  4  would be perfectly envisioned, but completely equivalent.  
      In accordance with  FIGS. 4 and 5 , the first stop  20  and the second stop  30  make up the projecting members respectively positioned on the direction of sliding motion at each end of the guide means  10 . Each projecting member is thus adapted to cooperate with the catching element  5 , by blocking movement along the direction of sliding motion.  
      In this method, the first stop  20  and the second stop  30  are attached to the support element  4 . They are moreover both constituted by at least one projecting member having a form appreciably complementary to a portion of the shoulder  8  arranged on the catching element  5 . Obviously, other forms fulfilling this same function could be adopted.