Abstract:
The invention relates to a security system for a motor vehicle opening leaf comprising means for detecting, remotely, the presence of a user&#39;s hand near the handle of the opening leaf, the detection means comprising at least one sensor ( 32, 34 ) capable of emitting or of receiving an electromagnetic signal, 
     borne by an internal module ( 36 ) which bears the sensor ( 32, 34 ) in such a way that the sensor ( 32, 34 ) is opposite an opening made in the bodywork panel ( 12 ). The security system further comprises a cover. The opening in the bodywork panel ( 12 ) is blanked off by a cover ( 40 ) made of a material that is transparent to the electromagnetic signal, the cover ( 40 ) being secured against an external face of the bodywork panel.

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to a security system for a motor vehicle opening leaf. 
     The invention relates more specifically to a security system for an opening leaf of a motor vehicle of the type in which the opening leaf is held in the closed position by a lock which is operated by means of a handle arranged on the outside of a bodywork panel of the opening leaf, of the type in which the security system comprises means for detecting, remotely, by means of an electromagnetic signal, the presence of a user&#39;s hand near the handle, and of the type in which the detection means comprise a control circuit and at least one sensor capable of emitting or of receiving the electromagnetic signal. 
     Such a system is described, for example, in document FR-A-2,733,783. The system described in this document proposes the use, as a means of detecting the presence of the hand, of an infrared-radiation sensor. This sensor “observes” an area in space around the handle so that when a user&#39;s hand approaches it, the infrared radiation emitted by the hand is picked up and analyzed by the sensor which is then capable of transmitting control information to an antitheft unit. 
     However, the invention can also be implemented in the context of a security system in which the detection means comprise an emitter which emits an electromagnetic signal intended to be received by a receiver, the path of the signal between the emitter and the receiver running, at least in part, on the outside of an external panel of the opening leaf. In this case, the presence of the hand is detected when the hand intercepts the path of the signal because, at that instant, the signal is no longer received by the receiver. 
     In this case, the signal may, for example, be infrared radiation. 
     In such a system, it is therefore necessary for the sensor or sensors to be able to “see” the environment on the outside of the handle. However, there is good cause to ensure that the detection means control circuit should itself be arranged on the inside of the bodywork panel of the opening leaf, for obvious esthetic reasons. 
     BRIEF SUMMARY OF THE INVENTION 
     The object of the invention is therefore to propose a new design of such a system which simultaneously allows for good integration into the overall style of the vehicle, and makes the system easier to mount, allowing the cost of performing this operation to be reduced, while at the same time guaranteeing that the mounting and the system are reliable, particularly by achieving a good seal to prevent dust or moisture from being able to disrupt the operation of the system. 
     To this end, the invention proposes a security system for an opening leaf of a motor vehicle of the type in which the opening leaf is held in the closed position by a lock which is operated by means of a handle arranged on the outside of a bodywork panel of the opening leaf, of the type in which the security system comprises means for detecting, remotely, by means of an electromagnetic signal, the presence of a user&#39;s hand near the handle, and of the type in which the detection means comprise a control circuit and at least one sensor capable of emitting or of receiving the electromagnetic signal wherein the hand-detection means comprise an internal module which bears the sensor and which is arranged on the inside of the bodywork panel in such a way that the sensor is opposite an opening made in the bodywork panel, and the opening in the bodywork panel is blanked off by a cover which is made of a material that is transparent to the electromagnetic signal, the cover being secured against an external face of the bodywork panel. 
     According to other features of the invention: 
     the cover comprises an external transverse wall which bears against the external face of the bodywork panel, and a tubular skirt which extends transversely inward from the external transverse wall through the opening in the bodywork panel and which cooperates in a sealed fashion with a casing of the internal module; 
     the tubular skirt extends around a lateral external wall of the casing, and a seal is inserted between the skirt and the lateral external wall of the casing; 
     the seal is borne by the skirt of the cover; 
     the seal is borne by the casing of the internal module; 
     the cover is secured to the bodywork panel; 
     the cover is fixed to the bodywork panel by elastic push-fitting means; 
     the cover is fixed to the bodywork panel by adhesive bonding. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other features and advantages of the invention will emerge from reading the detailed description which follows, for an understanding of which reference will be made to the appended drawings, in which: 
     FIG. 1 is a diagrammatic view in section on a horizontal plane of a motor vehicle handle comprising a security system in accordance with the teachings of the invention; 
     FIG. 2 is a diagrammatic view illustrating, in an enlargement, the cover which blanks off the opening in the bodywork panel; and 
     FIG. 3 is a detailed view illustrating an alternative form of the means of sealing between the cover and the casing of the internal module. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 illustrates a handle  10  for a motor vehicle opening leaf. 
     The handle  10  is intended to be mounted on an external bodywork panel  12  of the opening leaf. It essentially comprises a handle support  14  which is fixed on an inside face  16  of the panel  12 , and a lever  18  for grasping, which is arranged on the outside face  20  of the panel  12 , but which is articulated to the support  14  about an axis A 1  substantially parallel to a general plane of the panel  12 . The direction of the axis A 1  will arbitrarily be termed vertical while the direction perpendicular to the axis A 1 , and also parallel to the general plane of the panel  12 , will be said to be longitudinal. 
     Thus, the lever  18 , which runs longitudinally, comprises, at a longitudinal front end, an articulation tab  22  which extends toward the inside of the panel  12  through an opening made therein and which is mounted so that it can pivot on the support  14 . The lever  18  can therefore be brought from a position of rest, illustrated in FIG. 1, into an opening position (not depicted) in which its longitudinal rear end is moved away from the panel  12  transversely outward and in which the lever  18  actuates a transmission mechanism (not depicted) allowing, for example, a lock which holds the opening leaf in the closed position to be triggered. 
     To bring the lever  18  into its opening position, the user of the vehicle has to insert his or her hand between the bodywork panel  12  and a surface  26  for grasping of the lever  18  so that this lever can be pulled toward him or her, outward with respect to the panel  12 . 
     For this to be possible there is, between the panel  12  and the lever  18 , a space  28  which, in a plane perpendicular to the axis A 1 , is transversely delimited by an inward depression  30  in the panel  12  and by a surface  26  for grasping of the lever  18 , which face one another. 
     In accordance with the teachings of the invention, the handle  10  according to the invention comprises detection means which allow the presence of the user&#39;s hand in the space  28  to be detected before this hand has actually grasped the lever  18  via its surface  26  for grasping, and which are borne by the handle support  14  arranged on the inside face  16  of the panel  12 . 
     More specifically, the detection means comprise, in particular, an emitter  32  and a receiver  34  which are borne by an internal module  36  itself fixed to the handle support  14 . The emitter  32  and the receiver  34  are both connected to an electronic control module (not depicted) which is itself also borne by the internal module  36 . 
     According to the invention, the emitter  32  emits a signal of the electromagnetic type which is intended to be received by the receiver  34 . The signal is emitted in such a way as to follow a path which runs through the space  28  in such a way that when the user&#39;s hand enters this space  28 , it necessarily intercepts the path of the signal which means that the transmission of the signal between the emitter  32  and the receiver  34  is interrupted. As the receiver  34  no longer receives the signal, it deduces from this an information item relating to the presence of the hand in this space  28 . 
     The signal emitted by the emitter  32  and received by the receiver  34  is preferably a light signal in the visible range or in the infrared range. 
     As can be seen more specifically in FIG. 2, the emitter  32  and the receiver  34  are arranged substantially side by side, parallel to one another, set back toward the inside with respect to the bodywork panel  12 . 
     In accordance with the teachings of the invention, the two sensors  32 ,  34  are arranged facing an opening  38  (see FIG. 2) which is cut in the depression  30  in the bodywork panel  12 . In the embodiment illustrated, they are arranged facing the same opening  38 . 
     The signal emitted by the emitter  32  is therefore directed outward through the opening  38  and there is a reflector  39  borne by the lever  18  of the handle which reflects the signal back toward the receiver  34 , again through the opening  38 . 
     The control module which analyzes the signal received by the receiver  34  is therefore capable of detecting an interruption in the signal and, as appropriate, of transmitting a corresponding item of information to a unit for controlling the security system. 
     According to the invention, the opening  38  is intended to be blanked off by a cover  40 , an external transverse wall  42  of which extends substantially parallel to the bodywork panel  12 , on the outside thereof. 
     Of course, the external transverse wall  42  of the cover  40  is made of a material which is transparent to the electromagnetic signal. 
     In the embodiment of FIG. 2, it can be seen that the internal module  36  also bears, in front of each of the two sensors  32 ,  34  a lens  44 , the purpose of which is to focus and/or deflect the electromagnetic signal emitted by the emitter  32  or received by the sensor  34 . 
     Of course, the two lenses  44  are arranged between the corresponding sensor and the cover  40 . 
     The cover  40  comprises a tubular skirt  46  which extends axially inward from the external transverse wall  42 , through the opening  38  in the depression  30  in the panel  12 . As can be seen in FIG. 2, the internal axial end of the skirt  46  surrounds an external lateral wall  48  of a casing of the internal module  36 . The skirt  46 , around the entire periphery of its internal axial end, bears a seal which cooperates with the external face  48  of the casing in such a way that there is delimited, inside the skirt  46 , a closed housing protected from any dust or moisture. In this embodiment of the invention, the seal is a lip seal  50  which is borne by the skirt  46  and which presses against the external face  48  of the casing, which is of course of a complementary shape compared with the skirt  46 . 
     In the embodiment of FIG. 3, it can be seen that the seal may also be produced in the form of an O-ring  52  housed in a groove formed in an internal face of the skirt  46 . It is also possible to envisage for the seal  50  to be borne by the internal module  36 . 
     In accordance with the teachings of the invention, the internal module  36 , which bears the sensors  32 ,  34 , is intended to be mounted from the inside of the bodywork panel  12 , but, on the other hand, the cover  40  is intended to be mounted axially from the outside inward, by engaging the skirt  46  through the opening  38 . 
     Thus, the external transverse wall  42  of the cover  40 , which is of a larger size than the opening  38 , presses via a peripheral edge against the external face  20  of the bodywork panel  12 , more specifically against that part thereof which forms the surround of the opening  38 . Advantageously, around the opening  38 , the bodywork panel  12  has an indentation  54  toward the inside, so that the external transverse wall  42  of the cover  40 , which presses via an internal face  56  against the indentation  54 , has an external face  58  which is in the continuation of the external face  20  of the panel  18  in the region of the depression  30 . 
     The cover  40  will advantageously be fixed in place by means which cooperate with the bodywork panel  12 , which will make it possible simply and reliably to position the cover  40  very appropriately with respect to the panel  12 . This ensures that the security system is esthetically integrated into the external style of the vehicle. 
     Fixing may, for example, be by adhesive bonding, but it is also possible to envisage for the cover  40  to be fitted with elastic push-fit means (not depicted) capable of cooperating, for example, with the edge of the opening  38  in the panel  12 . 
     A particularly advantageous application of the invention consists in using the information about the presence of the hand to trigger, for example, a procedure of identifying the user whose hand is approaching. This procedure, controlled by the control unit and, for example, performed by a device involving transponders, may thus be performed before the user has even grasped hold of the handle lever  18 . If the user is an authorized user, the unit may then trigger an operation for unlocking the lock.