Abstract:
A vehicle door latch operably connected to a manually operable element selectively operable to disable a transmission path between the vehicle door latch and an internal door release means thereby to prevent release of the vehicle door latch by the internal door release means, wherein the manually operable element comprises means of illumination.

Description:
[0001]    This application claims priority to Great Britain patent application numbers GB 01 17446.5 filed Jul. 18, 2001.  
         BACKGROUND OF THE INVENTION  
         [0002]    This invention relates to child safety features on vehicle door latches, particularly to the visibility of child safety features.  
           [0003]    Most vehicle doors can be opened from both inside and outside. When a passenger is a child, curiosity may lead to the child opening the door from the inside when it is not safe to do so. For this reason it is desirable to be able to stop a child being able to open the door from the inside.  
           [0004]    It is known to have child safety features on vehicle door latches. Typically these can be turned on or off and when turned on prevent the door from being opened from the inside. However such child safety features are often difficult to locate, especially when there is a poor level of light such as at night. Also it is often difficult to tell if the child safety is on or off, again this is especially so in poor light conditions.  
         SUMMARY OF THE INVENTION  
         [0005]    It is an object of this invention to help overcome one or more of these problems, especially making a child safety feature easier to locate in the dark and/or to provide improvements in child safety feature for vehicle door latches.  
           [0006]    According to a first aspect of the invention there is provided a vehicle door latch operably connected to a manually operable element moveable between enabled and disabled positions thereby to affect a transmission path between the vehicle door latch and an internal door release means thereby to respectively enable or disable release of the vehicle door latch by the internal door release means, further comprising means of illumination for the manually operable element and preferably, wherein the manually operable element comprises means of illumination.  
           [0007]    Preferably the manually operable element is located on the shut face of a door which is inaccessible in use when the door is closed.  
           [0008]    Preferably the illuminating means illuminates in the colour yellow.  
           [0009]    Preferably the means of illumination is provided without combustion or perceptible heat, i.e. by luminescence. More preferably the means of illumination comprises a region of the manually operable element being luminescent such as phosphorescent or fluorescent.  
           [0010]    Preferably the means of illumination displays a colour when the transmission path is disabled and a different colour when it is enabled.  
           [0011]    Preferably the colour displayed when the transmission path is disabled is green and preferably the colour displayed when the transmission path is enabled is red.  
           [0012]    In one embodiment of the invention the manually operable element comprises a lever moveable between first and second positions, selection of which position determines whether the transmission path is enabled or disabled.  
           [0013]    In another embodiment of the invention the manually operable element comprises a rotatable component, the rotational position of which relative to the door latch determines whether the transmission path is disabled and more preferably may be rotated by insertion and rotation of a tool, such as a screwdriver.  
           [0014]    Preferably the rotatable component comprises an indicator panel, the panel comprising two coloured sections which rotate with the component in which the two coloured sections are preferably red and green and/or luminescent.  
           [0015]    According to a second aspect of the invention there is provided a vehicle door latch comprising a child safety feature having an illuminated actuator for enabling and disabling the child safety feature.  
           [0016]    According to a third aspect of the invention there is provided a vehicle door incorporating a vehicle door latch, in which a shut face comprises an aperture adjacent to the vehicle door latch through which a colour is displayed and when the rotatable component is rotated, when the transmission path is disabled, a different colour is displayed through the aperture. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    A vehicle door latch in accordance with the invention will now be described, by way of example only, with reference to the following drawings in which:  
         [0018]    [0018]FIG. 1 is a schematic view of a side a vehicle including a door with a vehicle door latch according to the invention,  
         [0019]    [0019]FIG. 2 is a view of a shut face of a vehicle door including a latch according to the invention,  
         [0020]    [0020]FIG. 3 is a view of a second embodiment of a shut face of a vehicle door including a latch according to the invention, and  
         [0021]    [0021]FIG. 4 is a view of a third embodiment of a shut face of a vehicle door including a latch according to the invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0022]    Referring to FIG. 1 there is shown a vehicle door  10  with a vehicle door latch  12  for latching and locking the door  10  to the vehicle  18 . The vehicle door latch  12  comprises a latch bolt  14  which engages and disengages with a striker  16  connected to the vehicle  18  so as to allow closing and opening of the door. The latch bolt is retained in its closed position by a pawl (not shown).  
         [0023]    The release of the latch  12  can be operated by an external door handle  20  when the latch is in an unlocked condition. The external handle  20  is connected to the pawl of the latch  12  by a transmission path  22  part of which could take the form of a rod and which allows release the latch  12  by pulling the handle  20 . The latch  12  may also be released by an internal door handle  24 . The internal handle  24  is connected to the pawl of the latch  12  by transmission path  26 , typically part of which is in the form of a Bowden cable and usually works in a substantially similar way to external handle  20 .  
         [0024]    There is also provided a child safety feature housed in latch  12 . This feature can be switched on or off. When the feature is switched off the latch  12  works as described above. When the feature is switched on, the transmission path  26  is disabled so that the internal handle  24  can no longer release the latch so the door cannot be opened from the inside. When the child safety feature is switched on, the latch may still be released by the external handle  20  when the latch is in an unlocked condition.  
         [0025]    [0025]FIG. 2 shows a first embodiment of a vehicle door latch  12   a  most of which is concealed by the shut face  32  of the door. The latch bolt  14  is located within an aperture  30 . The striker  16  enters through the aperture  30  to strike and engage the latch bolt  14 . The vehicle door latch  12   a  is attached to the door  10  by screws  34 .  
         [0026]    The child safety feature is switched on or off by lever  36 . The lever  36  may be pushed between an upwards position and a downwards position. In the upwards position the child safety feature is on. When pushed into the downwards position this turns off the child safety feature. Accordingly a manually operable element (lever  36 ) is provided to enable and disable the configuration.  
         [0027]    [0027]FIG. 3 shows a second embodiment of a vehicle door latch  12   b  similar to door latch  12   a  but with a different manually operable element. The child safety feature of the latch  12   b  is switched on or off by a rotatable component  38 . The rotatable component  38  can be rotated by insertion of a tool such as a screwdriver into the slot  39 . The component  38  has two rotational positions relative to the door latch  12  and the position it is in determines whether the transmission path is disabled or enabled, i.e. whether the child safety feature is on or off. When the slot  39  is vertical as shown in FIG. 2 the child safety feature is on. When the slot  39  is approximately twenty five degrees from vertical the child safety feature is off  
         [0028]    The two manually operable elements  36  and  38  of the door latches  12   a  and  12   b  respectively are luminescent, emitting light without perceptible heat and preferably emitting yellow light. This helps the elements to be found even in poor light conditions or at night. The elements may use a fluorescent or phosphorescent paint coating or could be made from a luminescent plastic.  
         [0029]    [0029]FIG. 4 shows a second embodiment of vehicle door latch  12   c  substantially similar to latch  12   b  except for the area surrounding the rotatable component  38 . Sharing the axis of rotation of the component  38  is a triangular indicator panel  40 . This panel  40  is fixed to the component  38  and rotates with it, behind the shut face  32 .  
         [0030]    In the shut face  32  of the door there is a circular aperture  42  which allows a user to view the surface of panel  40  behind the aperture  42 . In FIG. 3 the surface behind the aperture is green section  44 . Green section  44  is luminescent and emits green light, hence green light is visible through the aperture  40 . This green light indicates that the child safety feature is switched on. Green is used because it is associated with “go” or “on”. Located approximately twenty five degrees about the axis of rotation of component  38  is a red section  46  hidden by the shut face  32 . The red section  46  is luminescent and emits red light. However, when the switches are in the on position shown in FIG. 3 the red light is not visible to users. The red and green sections are luminescent in a similar way to the rotatable component  38 .  
         [0031]    When the rotatable component  38  is rotated through approximately twenty five degrees, anticlockwise when viewing FIG. 4, the child safety feature is turned off and the panel  40  is rotated by approximately twenty five degrees. In this position the surface behind the aperture  42  is the red section  46 , and the green section  44  is hidden by the shut face  32 . Red light is then visible through the aperture  40  and this red light indicates that the child safety feature is switched off. Red is used since this colour is associated with “danger” or “off” and represents an unsafe situation for children.  
         [0032]    In the third embodiment shown in FIG. 4 an adult concerned about child safety can easily see if the child safety feature is on or off even in poor light conditions such as at night. He or she can also easily locate the yellow light emitting component  38  and change its position if required.  
         [0033]    The foregoing description is only exemplary of the principles of the invention. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred examples of this invention have been disclosed, however, so that one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention.