Abstract:
The invention provides for an adjustment arrangement ( 16 ) for adjusting a camera and a camera arrangement. The adjustment arrangement ( 16 ) comprises a turn plate ( 20 ), an upper turn plate ( 24 ) and a gear wheel ( 22 ) adapted to be placed dependent on a lens ( 28 ) used.

Description:
BACKGROUND OF THE INVENTION 
     The invention provides for an adjustment arrangement for adjusting a camera and a camera arrangement comprising such an adjustment arrangement. The arrangement allows for adjusting the lens distance for setting the optical train of the camera. 
     Setting the lens distance is a major topic in camera systems, especially in a camera arrangement comprising a camera and a housing enclosing the camera. Usually, such a housing comprises an aperture defining the line of sight of the camera enclosed in the housing. A particular camera system known comprising a camera and a housing is a so-called dome camera. 
     A dome camera is a monitoring camera used in a protective system. Usually, the dome camera is incorporated within a hemispherical shaded dome made of plastics. Said dome is provided for protecting the camera against damage and vandalism. 
     Dome cameras have been used at flashpoints as well as in public means of transport both interior and exterior. A main advantage of such a dome camera is that it is not possible to determine the orientation of the camera hidden by the shaded dome. It is to be noted that in a dome camera the camera can be moved with respect to the dome forming the housing of the camera. 
     Document EP 1 729 269 A1 discloses a dome with optical correction for use in a vandal proof surveillance camera system. The dome comprises a transparent optical material, which itself comprises an inner surface and an outer surface. Both surfaces are essentially rotational symmetrical and exhibit non-spherical shapes. Said dome is used in a vandal proof surveillance camera system comprising said dome and a camera being pivotably mounted inside the dome. 
     It is to be noted that optical train is also referred to as optical assembly and is the arrangement of lenses to guide the line of sight. The position and angle of lenses are adjusted to guide the line of sight through the path required. 
     In a camera comprising a housing as illustrated above, it is a problem to be able to use the same parts in the optical train assembly to enable different lens settings and even to use different lenses to obtain the optimum lens configuration in the camera. The MBF (motorised back focus) also connects in this flexible setting. 
     SUMMARY OF THE INVENTION 
     The invention provides for an adjustment arrangement for adjusting a camera and a camera arrangement. 
     The construction saves costs in parts and assembly and can be considered as a flexible module. 
     In one embodiment, the lens distance setting assembly is built of a turn plate, an upper turn plate, a gearwheel and a sprocket stick. The gearwheel can be positioned in bottom position or in top position dependent on the lens used. The same gearwheel is adapted to be placed in bottom or in top position between the turn plate and the upper turn plate. 
     The foregoing summary as well as the following detailed description of preferred embodiments of the invention will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, embodiments of the invention are shown in the drawings. It should be understood however, that the invention is not limited to precise arrangements and instrumentalities shown. 
     It is self-evident that the features mentioned above and those which are still to be explained in the following text can be used not only in the respectively stated combination but also in other combinations or on their own without departing from the scope of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described in more details with reference to the drawings given below, in which: 
         FIG. 1  shows a camera arrangement comprising a camera enclosed by a housing and mounted on a adjustment arrangement in top view, 
         FIG. 2  shows the camera arrangement of  FIG. 1  in bottom view, 
         FIG. 3  shows the camera arrangement of  FIG. 1  in greater detail, 
         FIG. 4  shows the camera arrangement having a ultra wide lens, 
         FIG. 5  shows the camera arrangement having a tele lens, 
         FIG. 6  shows a section of the arrangement illustrating the setting for a tele lens, and 
         FIG. 7  shows a section of the adjustment arrangement illustrating the setting for an ultra wide lens. 
         FIG. 8  shows a section of the adjustment arrangement in a first operation condition. 
         FIG. 9  shows the section of the adjustment arrangement of  FIG. 8  in a second operation condition. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows in top view a camera arrangement  10  comprising a camera  12  enclosed by a housing  14  mounted on an adjustment arrangement  16 .  FIG. 2  shows the camera arrangement  10  in bottom view. 
       FIG. 3  shows the camera arrangement  10  in greater detail, the adjustment arrangement  16  comprises a turn plate  20 , a gearwheel  22 , an upper turn plate  24 , and a stick  26 , in this embodiment a sprocket stick. The turn plate  20  centers and holds the gearwheel  22 . The gearwheel  22  is formed as a cup with a base. 
     The housing  14  of the camera  12  comprises a lens  28  defining the line of sight of the camera. 
       FIG. 4  shows the camera arrangement  10  setted for an ultra wide lens  90 ,  FIG. 5  shows the arrangement  10  setted for a tele lens  92 . 
       FIG. 6  shows a section of the adjustment arrangement  16  comprising the turn plate  20 , the upper turn plate  24 , and the gearwheel  22  placed in bottom position to accommodate a tele lens on the inside of the base of the gearwheel  22 .  FIG. 7  shows the adjustment arrangement  16  comprising a gearwheel  22  placed in top position to accommodate an ultra wide lens on the outside of the base of the gearwheel  22 . 
     It is to be noted that the gearwheel  22  can be positioned dependent on the lens  28  used. It is to be noted that gearwheels  22  of different heights can be used to accommodate more different lens types. These gearwheels  22  can be swapped in the assembly by default. 
       FIG. 8  shows a section of the adjustment arrangement  16  comprising the turn-plate  20 , the upper turn plate  24  and the sprocket stick  26 . The sprocket stick  26  is loaded by a spring  70 . Arrow  72  indicates position of the gearwheel (not shown). 
     The sprocket stick  26  shown is in a static position and locked in its “splines” by pressure of the spring  70  and will be blocking the teeth of the gearwheel. This secures the rotation block of the gearwheel. 
       FIG. 9  illustrates the functional principle of the adjustment arrangement  16 . By pushing the sprocket stick  26  downwards in direction of arrow  80  against the springload will cause the splines to be unlocked. Therefore, the sprocket stick  26  can be turned (arrow  82 ) to drive the gearwheel. The gearwheel will be unlocked and turned in direction of arrow  84 . 
     The sprocket stick  26  can be made of molded POM, the upper turn plate  24  can be made of molded PC-ABS. Molded PC-ABS can be used for the turn plate  20 , Molded POM can be used for building the gearwheel. 
     For turning the gearwheel the sprocket stick  26  is in contact to the circumference of the gearwheel, in this manner rotation of the sprocket stick  26  is transferred to the gearwheel. In one embodiment the sprocket stick  26  is provided with teeth meshing with teeth of the gearwheel. 
     Different methods for transferring rotation of the stick to the gearwheel are possible according to the invention, e.g. a chain, a belt cord and sprocket and teeth meshing. In case the rotation is transferred by meshing teeth, the stick is built as a sprocket stick. In case the rotation is transferred by a chain or a cord belt, the stick can be built as a sprocket stick. However, in that case the stick does not have to be built as a sprocket stick.