Abstract:
The invention concerns a protective helmet comprising a shell ( 1 ) whereon are rotatably mounted a visor ( 2 ) and a chin strap ( 3 ), the lower portion of the visor ( 2 ) being urged to rest on a zone ( 4 ) of the chin strap ( 3 ) when they are lowered and the chin strap ( 3 ) capable of being raised about the visor ( 2 ). The invention is characterized in that the helmet is such that it comprises additional means for moving the visor ( 2 ) configured to bring its lower edge closer to or move it away from the raising trajectory of the support zone ( 4 ) on the chin strap ( 3 ).

Description:
FIELD OF THE INVENTION 
     The present invention concerns a protective helmet comprising, in a general manner, a shell on which is mounted a visor and a chin strap. 
     BACKGROUND OF THE INVENTION 
     The helmet according to the invention is intended for use by motorcyclists wanting an integral helmet, that is to say which provides complete protection of the motorcyclist&#39;s head, by the presence of a part that protects the chin, hereafter called the chin strap, while the mobility of the chin strap and the visor ensure that the helmet configuration can be changed. 
     A protective helmet, in particular for use by racing motorcyclists consisting of a visor mounted on the shell of a helmet, a chin strap attached to the shell and able to be raised over the visor towards the rear of the shell by a rotatable movement is described in patent EP-A-993 784. According to this prior art, the chin strap has a rotational axis that is offset upwards relative to the axis of the visor so that the chin strap can be raised without rubbing on the visor. According to this arrangement, the visor should rest on inner zone of the chin strap by its lower edge. 
     There is a need for a helmet with a chin strap and visor which are mobile in an upward direction so as to ensure that the visor effectively bears on the chin strap, in particular to form a seal when in the lowered position, while allowing the chin strap to be easily raised above the visor. 
     One aim of the invention is to propose a solution to this problem. 
     SUMMARY OF THE INVENTION 
     The invention then allows the chinstrap and the visor to coact in the lowered position to form a perfect seal. In particular, according to a preferred embodiment, the visor is able to coact with an outer part of the chinstrap which has an edge behind the visor so that it can be blocked perfectly and the seal maximized. 
     According to a preferred embodiment, the visor is not only rotatably mounted relative to the shell but also has additional mobility in inclination along an axis of rotation that is different from that of its rotation relative to the shell so that its inclination can be changed and the visor moved out of the path of the upward trajectory of the chinstrap. 
     According to another advantage of the invention, the mobility of the visor is interlocked to that of the chinstrap so that raising the chinstrap simultaneously raises the visor. Moreover, the interlocking means can be configured so that the visor can be raised faster than the chinstrap, which releases the visor from its trajectory on the first phase of chinstrap raising. 
     It will be noted that there are many possible configurations of the helmet according to the invention, in particular for coacting of the chinstrap and the visor. 
     Other aims and advantages will become apparent in the description of a preferred embodiment which follows, which however is not restrictive. 
     The present invention concerns a protective helmet with a shell on which are rotatably mounted a visor and chinstrap, the lower part of the visor resting against a zone of the chinstrap when they are lowered, the chinstrap being upwardly movable around the visor. According to the invention, the helmet has additional means for moving the visor which are configured to bring its lower edge closer or move it away from the upward trajectory of the support zone on the chinstrap. 
     According to the invention, this helmet may take the form of the preferred embodiment described below:
         the additional mobility means are means for inclining the visor,   the inclination means include, on each side of the shell, a rod mounted to swivel at one of its ends on the visor, and the other end on the rotational axis of the visor on the shell,   it includes a lateral support on each side joined to the visor in the form of an oblong guide hole for the rotational axis,   it includes means for interlocking the additional mobility of the visor with raising of the chinstrap,   it includes means for interlocking the rotation of the visor relative to the shell with raising of the chinstrap,   it includes means for interlocking the rotation and inclination of the visor with raising of the chinstrap, the aforementioned means comprising:       

     a rotatably mounted cam on the shell and the means for driving the cam rotatably by rotation of the chinstrap during its first raising phase, 
     at least one finger joined to the cam which presses on a bearing surface of the rod so as to drive the rod and the visor rotatably, 
     a cavity formed in the cam and able to bear on an upper stop and a lower stop forming the limits of the oblong hole so as to drive the lateral support around the rotational axis,
         the drive means comprise a drive device joined to the cam and guided in a track formed in a drive part joined to the chin strap, the said track comprising a roughly radial part within which the drive device is driven rotatably and a roughly tangential part within which the drive device is not driven rotatably,   the cam has a finger which exerts a pressure on a bearing surface of the rod so as to drive the rod and the visor rotatably in an upward movement when the chinstrap is slack in the lowered position and the visor is lowered,   the means for interlocking the visor in rotation relative to the shell with raising of the chinstrap are configured in order to generate higher angular velocity for the visor than for the chinstrap.       

    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings attached are given as examples and are not restrictive. They represent only one embodiment of the invention to allow it to be easily understood. 
         FIG. 1  is a side view of a helmet according to the invention with the chinstrap and visor lowered in the active position. 
         FIG. 2  shows a first phase of visor and chinstrap movement. 
         FIG. 3  shows a later phase with additional mobility of the visor. 
         FIG. 4  shows a more raised position of the chinstrap relative to the shell. 
         FIG. 5  shows lowering of the visor when the chinstrap is retracted. 
         FIG. 6  shows the return of the chinstrap over the shell and  FIG. 7  shows a position of the chinstrap reaching its lowered position with mobility of the visor. 
         FIGS. 8 to 12  show successively a view of the rod, the visor, the side support, the cam, and the chinstrap coacting in the invention. 
     
    
    
     DETAILED DESCRIPTION 
     By reference to  FIG. 1  and in a known manner in its own right, the invention has the form of a helmet with a shell  1  protecting the rear of the motorcyclist&#39;s head. On each side  6  of shell  1  are means for mounting a chinstrap  3  and visor  2 . More precisely, chin strap  3  and visor  2  are articulated relative to shell  1  through rotational axis  5 . In the example shown, it consists of a single axis of rotation for the chinstrap and the visor. 
     In the lowered position, the lower portion of visor  2  bears on zone  4  formed appreciably in the upper part of chinstrap  3 . More precisely, in the example illustrated and as shown on  FIG. 2  in particular, bearing zone  4  consists of an edge  21  in front of which is positioned the lower portion of visor  2 . In this configuration, the unit is very tight and has high mechanical strength. Indeed, in its lower portion, visor  2  is maintained perfectly by the chinstrap at the level of bearing zone  4  with edge  21 . 
     To allow chin strap  3  to be raised without rubbing against the outer surface of visor  2 , visor  2  is provided with additional mobility so that its lower edge can move closer or away from the upward trajectory of support zone  4  of chin strap  3 . 
     In the example shown, the additional mobility consists of an inclination of visor  2  along an axis of rotation different from axis  5 . 
     Thus, as shown on  FIG. 3 , the means of inclination allow the lower edge of the visor to be inserted before chin strap  3  passes over visor  2 . 
     The various figures show an embodiment of the means of inclination. In this context, at the level of each side  6  of shell  1  is mounted a rod  7  swiveling at one of its ends on visor  2  and assembled rotatably at its other end on axis of rotation  5 . It will be easily understood that additional rotatable mobility is generated for the visor by means of rod  7 . 
     Thus, rotation around axis  5  is created when visor  2  is raised, as shown on  FIG. 2 , followed by or simultaneously with an inclination as shown on  FIG. 3 . 
     There is an advantage in limiting the possibilities of angular displacement between rod  7  and visor  2  so as to limit the movement. 
     Still referring to the figures, a side support  8  is present at each side  6  and is formed joined to visor  2 , of which it may constitute the simple extension. The side support has an oblong hole  9  in it to guide the axis of rotation  5 . 
     Visor  2  may be moved manually by the user both rotatably around axis  5  and in inclination through rod  7 . However, there is an advantage in visor displacement being generated automatically on raising chin strap  3 . 
     The means for controlling the displacement of visor  2  are described for this purpose, both in its rotation relative to shell  1  and in its additional mobility in inclination. The example shown is not restrictive and interlocking could for instance only relate to the additional mobility or the rotation of the visor. In addition, the control means proposed here may be appropriate to drive a visor  2  without additional mobility. 
     The interlocking means illustrated here show means joined to chin strap  3  capable of generating a drive force on visor  2  through cam  10 . 
     Cam  10  is positioned between visor  2  and chin strap  3  and is hidden by the side of chin strap  3 . Cam  10  is rotatably mounted on shell  1  by axis  16 . 
     Drive part  19  is formed joined to the side of chin strap  3 , which in this case is roughly circular even though this shape is not restrictive, and shows a displacement track  14  for a drive body  13  joined to cam  10 . 
     This part  19  can be added to chin strap  3  or form a single part with the latter which it then forms part of. 
     Track  14  has a radial part  14   a  which, when the drive device  13  is positioned in this part, allows part  19  to apply a drive force on cam  10 . Track  14  also has a tangential part  14   b  in which, by tangential orientation of the track relative to the direction of rotational movement of part  19 , no effort is transmitted to drive device  13 . 
     Thus, cam  10  is driven on a first phase of raising chin strap  3  when drive body  13  is present in radial part  14   a  of displacement track  14  of part  19 . During a subsequent raising phase, after the continued rotation of part  19  body  13  reaches tangential part  14   b  of displacement track  14  of part  19 , which causes no further rotation of cam  10 . 
     Cavity  15  is arranged in cam  10  so as to form a wall for the application and guidance of upper stop  17  and lower stop  18  executed in relief at the two ends of oblong hole  9  of lateral support  8 . 
     The coacting of stops  17 ,  18  and cavity  15  ensures the position of the side support  8  changes relative to rotational axis  5 . In  FIG. 1 , rotational axis  5  is at the level of the upper stop  17 , which generates an active position in which rod  7  and side support  8  are not inclined relative to one another. In  FIG. 2 , axis  5  has evolved in oblong hole  9  and reaches, in  FIG. 3 , lower stop  18 . In this latter position, the inclination of the visor is maximum, showing the angular offset of rod  7  compared to side support  8 . 
     In addition to the inclination produced for visor  2 , cam  10  allows visor  2  to be raised around shell  1 . 
     To this end, cam  10  has a finger  11  positioned towards its upper edge and capable of exercising a force on bearing surface  22  in the form of a hook formed on link rod  7  so that finger  11  pushes on surface  22  when cam  10  is activated rotatably by raising chin strap  3 .  FIG. 2  shows this pushing phase. 
     After completely raising visor  2 , a stop not shown is advantageously created to limit raising. 
     The various kinematic elements of the system described here can be advantageously configured to cause faster angular displacement of visor  2  relative to chin strap  3 . This occurs, in particular, by positioning the point of contact of finger  11 /surface  22  close to the axis of rotation  5  so as to generate considerable angular displacement from a low tangential displacement of the drive elements. 
     The case shown corresponds to this embodiment. 
       FIGS. 1 to 7  show successive phases for use of the protective helmet described here. 
     Thus, in  FIG. 1 , chin strap  3  and visor  2  are in the lowered active protection position. 
     In  FIG. 2 , the user has begun raising the chin strap, which causes quicker raising of visor  2 . 
     At the stage of  FIG. 3 , after raising visor  2  along axis  5 , the latter creates additional mobility so as to insert its lower edge relative to the raising trajectory of support zone  4  of chin strap  3 . 
     Chin strap  3  can then be raised freely without rubbing on visor  2 . 
     For instance, the position illustrated in  FIG. 4  may be reached. 
       FIG. 5  shows a possibility according to which the user uses the helmet in the “jet” position in which visor  2  is folded back but chin strap  3  remains inactive. 
     In  FIG. 6 , following this position, the user lowers chin strap  3 . On the return of chin strap  3 , drive device  13  once again adopts tangential portion  14   b  of track  14  up to radial part  14   a  which is roughly perpendicular to it. This leads to the opposite action of cam  10  inclining towards the bottom quickly. 
     To allow a return of chin strap  3  to the lowered position when visor  2  has already been lowered, a mechanism allows prior raising of the visor as shown in  FIG. 6 . 
     More exactly, finger  12  is formed on cam  10  to coact with a surface  23  formed at the rear of rod  7  so that finger  12  pushes surface  23  when cam  10  is actuated rotatably by lowering chin strap  3 . 
     At the end of rotation, finger  12  is released from surface  23  thereby making it possible for visor  2  to be lowered and applied on zone  4 . 
     This causes a return to the initial position shown on  FIG. 1  and  FIG. 7 . 
     In the low position, chin strap  3  is maintained in position by a lower stop such as lug  24 . A locking system is advantageously envisaged in order to fix the chin strap in this position. 
     REFERENCES 
     
         
           1 . Shell 
           2 . Visor 
           3 . Chin strap 
           4 . Bearing zone 
           5 . Rotational axis 
           6 . Shell side 
           7 . Rod 
           8 . Lateral support 
           9 . Oblong hole of lateral support 
           10  Cam 
           11  Finger 
           12  Finger 
           13  Drive device 
           14  Displacement track 
           14   a . Radial part 
           14   b  Tangential part 
           15 . Cavity 
           16 . Cam axis of rotation 
           17 . Upper stop 
           18 . Lower stop 
           19 . Drive part 
           21 . Edge 
           22 . Raising bearing surface 
           23 . Lowering bearing surface 
           24 . Lug