Abstract:
An external control stand for a self-propelled construction machine. The construction machine has a working component that can be operated from the external control stand. The invention includes a lighting device for illuminating a ground section on the external control stand, as seen in the direction of travel, in front of, behind and/or below the external control stand.

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to an external control stand for a construction machine configured for controlling at least one working component of the construction machine. 
     FIELD OF THE INVENTION 
     Such external control units (“external control unit” and “external control stand” will be used interchangeably in the following) for self-propelled construction machines are known in practice. For example, they are used in road pavers in order to carry out adjustments to a working component of the road paver primarily while driving. For example, during the paving process, it can be necessary to adjust the screed, particularly an extending screed with variable width that is mounted to the road paver in order to adapt its position to the course of the road or to avoid obstacles. 
     It is further known that road pavers are often used for road construction in the dark or in road tunnels. In order to guarantee that the operating personnel have sufficient lighting of the paving path, auxiliary lights are used. In the case of conventional road pavers, these auxiliary lights are put to use with external power outlets. Detrimental in this is that it is necessary to provide external power outlets and that these can become dirty. These separate auxiliary lights must furthermore be supported or held in a suitable manner. 
     The object of the present invention is to provide an external control unit for a construction machine whereby this external control stand allows improved operation of the construction machine while using the simplest possible design measures. 
     SUMMARY OF THE INVENTION 
     This object is solved by an external control stand for a construction machine with the features of the present invention. 
     According to the invention, a lighting device is provided on the external control stand of a self-propelled construction machine. The lighting device is used to illuminate a ground section that is located, seen in the direction of travel, in front of, behind and/or below the external control stand. This lighting device offers the advantage that there is no need for auxiliary light that is supplied by means of an external power outlet. Consequently, it is not necessary to provide a power socket, nor is it necessary for operating personnel to hold or clamp on an additional light. There is consequently no impairment in the handling of the road paver in the dark. Suitable as illuminants for the lighting device are, for example, a single LED or an array of LEDs. 
     The lighting device is preferably integrated into the external stand. For this purpose, the housing of the external control unit has, e.g., a corresponding recess on the surface that is facing towards the road surface. Advantageous in this is that the lighting device is protected against mechanical impairments. Additional built-on parts are furthermore avoided. 
     It is expedient if a transparent and/or translucent cover is provided for the lighting device. Such a covering protects the lighting device effectively against dust, splash water and other environmental influences. The covering is nevertheless light-permeable, so that the effect of the lighting device is ensured. The covering is preferably manufactured from a suitable plastic. An optional seal on the covering additionally prevents dust or humidity from penetrating into the lighting device. 
     It is particularly advantageous if the covering of the lighting device is attached to the external control unit with a detachable connection. This makes it possible to carry out maintenance work on the lighting device without dismantling larger parts of the external control unit. This enables easier maintenance of the lighting device. 
     In an advantageous variant of the invention, the external control stand has a diffuser lens for the lighting device. A desired diffusion or attenuation of the light beam can be adjusted by means of an appropriate pattern in the diffuser lens. 
     It is particularly advantageous if the lighting device is fixed with regard to its orientation relative to the external control stand. This allows for a defined, stable and vibration-resistant illumination of the ground section. 
     It can, however, also be advantageous if the lighting device is variably adjustable with respect to its orientation relative to the external control stand. As a result, the light beam can be directed in particular directions in order to have an active influence on the illuminated ground section. By means of suitable attenuation devices, it is possible to avoid disadvantages if vibrations arise. 
     It is particularly advantageous if the lighting device can be activated and/or deactivated from the external control unit. In this way, the operating personnel at the external control stand can themselves control when the lighting device is activated or deactivated. 
     It is expedient if the brightness of the lighting device is variable. In this way, the illumination of the ground section can additionally be influenced and adapted to the external conditions. 
     In a particularly advantageous variant of the invention the lighting device is configured for automatic activation and/or deactivation by means of a light-sensitive sensor. The lighting device can consequently, e.g., when driving into a road tunnel, be activated without the assistance of the operating personnel, so that the operating personnel are not distracted while operating the construction machine. 
     In order to avoid loose cable connections, a device for the power supply can be provided that is shared by the external control stand and the lighting device. 
     It is particularly advantageous if the external control stand is disposed on a working component that can be moved and/or pivoted relative to a supporting frame of the construction machine, for example, on a screed or an extendable screed. In this way, when the working component is pivoted or moved, the lighting device moves along with it, so that optimal illumination of the changed ground section is guaranteed. 
     The invention also relates to a construction machine, for example, a road paver or a feeder, with an external control unit of the type described above. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the following, an advantageous embodiment of the invention is described in more detail using the accompanying drawings. In detail, shown are: 
         FIG. 1  a side view of an external control stand according to the invention on a road paver given as an example of a self-propelled construction machine and 
         FIG. 2  a schematic bottom view of an external control unit according to the invention with a lighting device according to the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows a schematically depicted construction machine  1 , which, in this embodiment, is a road paver. The construction machine  1  has a supporting frame  1   a . To control the main functions, such as, for example, the driving and steering of the construction machine  1 , the construction machine  1  has a driver&#39;s cabin  2  that holds a control console  3 . On its rear end as seen in the direction of travel, the construction machine  1  has a working component  4  in the form of a screed. The working component  4  is attached to the construction machine  1  in such a manner that it can be shifted, pulled out or extended, and pivoted. 
     For controlling the working component  4 , the construction machine  1  has an external control stand  5  that is arranged, when seen in the direction of travel, behind the working component  4 . The external control stand  5  is primarily provided to align the working component  4  according to the course of the road or obstacles during a paving procedure. The external control stand  5  is normally operated by one person, who moves on foot along with the construction machine  1 . The working component  4  can be operated electro-hydraulically. 
     The external control stand  5  comprises a holding device  6  for mounting of the external control stand  5  to the working component  4 . The external control stand  5  is thereby mounted to the working component  4  in such a manner that it always moves along with the working component  4  when it is pivoted and extended laterally. An operating panel  8  is attached to the holding device  6  by means of a holding receptacle  7 . The operating panel  8  has a housing  9  that is made of plastic and that has on its upper side operating elements  10  for controlling the working component  4 . On the bottom side of the housing, the holding receptacle  7  is integrated into the housing. 
     According to the invention, the housing  9  of the operating panel  8  additionally has a lighting device  11  that is integrated into the housing  9 . The lighting device  11  is provided for the purpose of emitting visible light  12  from the external control unit  5 . In this way, the generated light  12  makes it possible, for example, to detect an obstacle  13  on the driving route  14  and to steer the working component  4  around the obstacle correspondingly. 
     The arrangement of the lighting device  11  on the external control unit  5  according to the invention is explained in more detail on the basis of  FIG. 2 , which depicts the bottom side of the operating panel  8  schematically. The housing  9  has a plurality of electrical connections  9   a  that are used as an interface between the operating panel  8  and the working component  4  or the construction machine  1  respectively. As described above, the lighting device  11  is integrated into the housing  9  of the operating panel  8 . For this purpose, the housing  9  has a recess that has approximately the size of the lighting device  11  and that accommodates the lighting device  11 . The housing  9  has an electrical connection that is provided therein and that is used for an illuminant  15  of the lighting device  11 . The illuminant  15  is covered, and consequently protected from dust, splash water or other environmental influences, by a cover  16 . The cover  16  is executed in a light-permeable (translucent) manner and can additionally configured to be is transparent. The cover  16  can be used as a diffuser lens in order to achieve the optimal illumination of the driving route  14 . 
     The cover  16  is attached to the housing  9  of the operating panel  8  by means of a screw threaded connection  17 . The orientation of the lighting device  11  on the external control unit  5  is preferably configured in such a manner that the visible light  12  is not obstructed by the working component  4 . 
     During the operation of the construction machine  1 , the lighting device  11  can be activated and deactivated by means of the operating panel  8 . In the switched-on state, the illuminance of the lighting device  11  amounts to at least 15 lx, whereby the object distance (i.e., the distance from the driving route  14 ) amounts to approximately 1.4 meters. The area illuminated in this way is approximately one square meter. This corresponds to a radiation angle of the illuminant  15  (i.e., the aperture angle of the light cone emitted by the lighting device  11 ) of roughly 65° to 70°. The mean angle between the lighting device  11  that is integrated into the housing  9  and the driving route  14  amounts to between 30° and 80°, preferably however at least 45°, with respect to the vertical. 
     Based on the depicted embodiment, the external control stand  5  according to the invention can be modified in various ways. For example, it would be possible to provide a light-sensitive sensor  18  for the lighting device  11 , whereby this light-sensitive sensor  18  automatically activates the lighting device  11  at twilight or in the dark, for example, when driving into a road tunnel. The sensor  18  could, e.g., also be arranged in front of the working component  4  when seen in the direction of travel of the construction machine  1 . The brightness of the lighting device  11  could furthermore be variably adjustable. It could furthermore be provided that the lighting device  11  is variably adjustable with regard to its orientation relative to the external control stand  5 . In a further variant of the invention, the radiation angle of the lighting device  11  could be variably adjustable. For example, this could be realized by means of a variable lens or an adjustable reflector.