Abstract:
A structure of overhead lamp and mounting bracket for constructional vehicle has developed to tilt the illuminating angle by controlling the position of slits at the lateral sides of bracket. The lamp is securely fixing at the controlled position at one of 4 positions and the position controlling slits. The main case is securely fixed to the bracket by installing a connection screw and a hinge bolt for restricting unwanted rotation of the hinge bolt. Accordingly, since a position controlling rib having a position controlling slit is extended rearward from side supporters, the illumination angle can be controlled within a greater range. The main case can be supported at 4 points through the plurality of position controlling slits. Furthermore, by fitting the connection screw with an outer circumferential recess of a hinge bolt fastening lever, rotational separation of the hinge bolt and change of the illumination angle of the main case can be prevented.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to the structure of overhead lamp and mounting bracket for constructional vehicle. More particularly, the overhead lamp with mounting bracket installed on a roof of the constructional vehicle has capable to control the illuminating direction by adjusting the tilt angle. A pair of arc-slits disposed at lateral surfaces of the mounting bracket has adopted for tiling and securely fixing the lamp at a controlled position. 
         [0003]    2. Description of the Related Art 
         [0004]    As generally known, a constructional vehicle has equipped with a pair of overhead lamps to secure the front views, while the vehicle is operating at night or in a dark place such as a tunnel. The overhead lamp has assembled with a lamp chamber consisted a main housing and a transparent cover, sub-housing consisted lens and reflecting mirror and mounted in the lamp chamber, and a head-lamp unit mounted in the sub-housing. 
         [0005]    The overhead lamp unit comprises a bulb as a light source, and a bulb adaptor that supports the bulb. For the bulb, the halogen bulb is generally used for adopting temperature radiation system. Alternatively, a gas discharge bulb is adopted a luminescence system. 
         [0006]    The halogen bulb is relatively darker than the gas discharge bulb since it has a low luminous flux, but is cheaper and therefore generally applied to mid and low-end cars. On the other hand, although being expensive, the gas discharge bulb is even brighter than the halogen bulb since having a high luminous flux, and therefore is generally applied to high price cars. 
         [0007]    Recently, researches for headlamp assemblies using an LED lamp as the light source have been actively performed. 
         [0008]    Especially, the LED lamp is advantageous in terms of general aspects including a processing rate, power consumption and the lifespan owing to its properties as a semiconductor, and therefore has been widely used as an electronic indication part in various electronic appliances. Furthermore, as high-brightness LEDs are introduced recently, the LED lamp has been spotlighted as a high-tech future light source. The LED lamp is not only power-saving in comparison with other conventional bulbs, but also achieves excellent color rendering in comparison with conventional color lighting using glasswork, coating, a filter and so on, since having elements of a variety of colors. In addition, the LED lamp has a great durability. Therefore, the maintenance cost and the replacement cost for the vehicle headlamp assembly can be reduced. 
         [0009]      FIG. 1  is a perspective view showing a pair of overhead lamps mounted on a heavy equipment or constructional vehicle. 
         [0010]    Referring to  FIG. 1 , since the overhead lamp has a high brightness and excellent durability as described above, the LED lamp is generally used to a heavy equipment vehicle  2  in a constructional site, that is a poor environment, or an off-road vehicle (not shown) such as a jeep. 
         [0011]      FIG. 1  shows the heavy equipment vehicle  2  mounted with a lamp apparatus  6  at an upper surface of a roof panel  4  thereof. The appearance of the lamp apparatus  6  is constituted by a hexahedral case  8 . In the center of a lower surface of the case  8 , a fixed rod  10  is fixed to the roof panel  4 , being equipped with a connection bolt  12  at a lower end thereof. 
         [0012]    The conventional lamp apparatus  6  is immovably fixed to the upper surface of the roof panel  4 . However, it is disadvantageous to fix the lamp apparatus  6  to the roof panel  4  in an angle-uncontrollable state because the lamp apparatus  6  would illuminate different positions according to the working positions by the heavy equipment vehicle  2 . 
         [0013]    For example, more specifically, in case of excavating the ground or a wall, the lamp apparatus  6  needs to have totally different illumination angles to adequately function. That is, when the lamp apparatus  6  is immovably fixed to the upper surface of the roof panel  4 , the working areas can not be properly illuminated. 
         [0014]    Accordingly, a structure for supporting a lamp apparatus has recently been developed as shown in  FIGS. 2 and 3 . 
         [0015]      FIG. 2  is an exploded perspective view of the lamp apparatus supporting structure for a vehicle according to another conventional art.  FIG. 3  is a side view of the lamp apparatus supporting structure of  FIG. 2 , showing an illumination angle range. 
         [0016]    Referring to the drawings, another conventional lamp and supporting structure, a lamp apparatus  106  comprises a main case  108  equipped with a plurality of LED lamps (not shown) mounted therein. The main case  108  includes a connection hole  112  on both sides, and a front cover  110  at the front. In addition, a connection protrusion  114  is formed on a lower rear surface of the main case  108 . 
         [0017]    The main case  108  is fixed to the roof panel  4  of the heavy equipment vehicle  2 , and a fixing unit  120  for controlling the illumination angle is additionally provided. The fixing unit  120  comprises a center supporter  122  fixed to the roof panel  4  apart from a lower part of the main case  108 , and side supporters  124  vertically extended upward from both ends of the center supporter  122  and brought into close contact with lateral sides of the main case  108 . A hinge hole  126  is formed at each side supporter  124 , corresponding to the connection hole  112 . 
         [0018]    The center supporter  122  has a penetration hole  218  substantially in the middle. In addition, a position determining rib  130  is extended from a rear side of the center supporter  122  as seen from the front to the rear of the vehicle. More specifically, the position determining rib  130  is bent in a regular arc form upward from the center supporter  122 , and includes a position determining slit  142  formed in a length direction thereof. 
         [0019]    A washer  136 , a nut  134  and a fixing bolt  132  are sequentially connected through the penetration hole  128  of the center supporter  122 , thereby connecting the center supporter  122  to the upper surface of the roof panel  4  ( FIG. 1 ). 
         [0020]    In a state where the connection holes  112  formed on the main case  108  and the hinge holes  126  formed on the side supporter  124  are correspondingly connected to each other, a washer  140  and a hinge bolt  138  are sequentially connected to the connection holes  112  through the hinge holes  126 . Therefore, the main case  108  is rotationally hinged on the fixing unit  120 . 
         [0021]    Next, when the connection protrusion  114  of the main case  108  is engaged with the position determining slit  142  of the position determining rib  130  formed at the fixing unit  120  and a position fixing lever  141  is connected to the connection protrusion  114 , the main case  108  can be rotated with respect to the fixing unit  120  fixed to the roof panel  4  of the vehicle. Accordingly, the illumination angle of the LED lamps (not shown) provided in the main case  108  can become controllable as shown in  FIG. 3 . 
         [0022]    According to the above-described conventional lamp apparatus supporting structure for a vehicle, however, since a displacement range of the illumination angle of the main case  108  is restricted within the length of the position determining slit  132 , the actual illumination angle is approximately 10-12 degrees as shown in  FIG. 3 . 
         [0023]    Moreover, since the conventional lamp apparatus supporting structure is supported by 3 points, that is, both sides of the main case  108  and the connection protrusion  114  formed at the rear middle part of the main case  108 , it is difficult to securely fix the main case  108  with respect to the fixing unit  120 . More specifically, while the heavy equipment vehicle  2  is moving to work in such a poor work environment, the position fixing lever  141  fixed merely by one position may be unfastened, thereby hindering the normal performance of the lamp apparatus. 
         [0024]    Meanwhile, considering that the conventional lamp apparatus supporting structure is mainly applied to the heavy equipment vehicle which works at a poor environment such as a construction site generating much vibration with an uncompleted underground construction, the hinge bolt  138  would be transmitted with the vibration of the vehicle and easily separated from the connection hole  112  of the main case  108 . As a result, unwanted change of the illumination angle of the lamp apparatus  6  may be caused. 
       SUMMARY OF THE INVENTION 
       [0025]    Accordingly, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a supporting structure for an overhead lamp for constructional vehicle, capable of increasing an illumination angle range by forming position controlling slits at lateral sides of a bracket, more securely fixing a main case of the lamp apparatus as position-controlled by supporting the main case through 4 points using a plurality of hinges and a plurality of the position controlling slits, and also securely fixing the main case to the bracket by connecting a connection screw that fixes a hinge bolt, restricting undesired rotation of the hinge bolt. 
         [0026]    In accordance with the present invention, the above and other objects can be accomplished by the provision of a structure for supporting a lamp apparatus including a plurality of LED lamps mounted in a main case, a lamp PCB mounted with parts and sockets for operating the LED lamps, a collimate lens connected to a front side of the LED lamps to reflect light by a predetermined angle, a protection board formed at the front side of the collimate lens to protect the LED lamps from contaminants, a cover covering the protection board, being connected to the front of the main case, and a packing material interposed between the cover and the main case, the lamp apparatus supporting system comprising the main case mounted with various parts required for the lamp apparatus therein, including a hinge hole formed on a central part of both sides thereof, and a fixing recess formed on the both sides thereof, thereby achieving a 4-point supporting system, a fixing unit fixing the main case to a roof panel of a heavy equipment vehicle and including a penetration hole and a position controlling slit respectively corresponding to the hinge hole and the fixing recess of the main case, a hinge bolt fastening lever including a hinge bolt formed on the front side thereof to connect the main case to the fixing unit in a hinged manner, and a fixing bolt fixing both sides of the main case to the fixing unit through the position controlling slits of the fixing unit to have a predetermined illumination angle. 
         [0027]    The main case may include a plurality of heat sinks formed on an outer surface of the main case to increase a contacting area with the air. The main case may be formed of a high-conductivity material such as aluminum. The fixing unit may include a center supporter fixed to the roof panel of the vehicle, a side supporter vertically extended upward from both ends of the center supporter and brought into close contact with lateral sides of the main case, including a penetration hole corresponding to the hinge hole, and a position controlling rib extended rearward from upper parts of the side supporters and each formed with the position controlling slit in the center thereof. 
         [0028]    The position controlling slit may have an arc form cut out by ¼ length of a circular circumference. The main case may be rotated through the position controlling slit by an illumination angle of 90 degrees. 
         [0029]    The hinge bolt fastening lever may further include a connection screw brought into close contact with any one outer circumferential recess of the hinge bolt fastening lever and connected with the connection hole of the fixing unit, thereby preventing rotation and separation of the hinge bolt fastening lever. 
         [0030]    The fixing unit may have a U-shape to receive and fix the main case therein. The heat sinks may be connected to a lower surface and a rear surface of the main case corresponding to a direction of the airflow. The center supporter may include a connection rod formed with a male screw thread on an outer circumference thereof to be fixed to the roof panel, and a nut. 
         [0031]    According to the lamp apparatus supporting structure for a vehicle as described above, the illumination angle of the lamp apparatus can be increased since the position controlling rib having the position controlling slit is extended to the rear side of the lateral sides of the side supporters and also provided at both sides of the fixing unit. Moreover, the main case is fixed to the fixing unit through a plurality of the position controlling slits that is, supported by 4 points, thereby being more securely fixed. Also, by fitting the connection screw with any one circumferential recess of the hinge bolt fastening lever, undesired separation of the hinge bolt and undesired change of the illumination angle of the main case can be prevented. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0032]      FIG. 1  is a perspective view showing an overhead lamp fixed on a roof of the heavy-equipment or constructional vehicle. 
           [0033]      FIG. 2  is an exploded perspective view of a conventional overhead lamp and supporting structure. 
           [0034]      FIG. 3  is a side view of the overhead lamp and supporting structure of  FIG. 2 , showing an illumination angle range. 
           [0035]      FIG. 4  is an exploded perspective view of an overhead lamp and supporting structure for a constructional vehicle according to an embodiment of the present invention; 
           [0036]      FIG. 5  is a perspective view of the overhead lamp and supporting structure for the constructional vehicle according to the embodiment of the present invention. 
           [0037]      FIG. 6  is a side view of the overhead lamp and supporting structure of  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0038]    Hereinafter, an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings. 
         [0039]      FIG. 4  is an exploded perspective view of an overhead lamp and supporting structure for constructional vehicle according to an embodiment of the present invention.  FIG. 5  is a perspective view of the overhead lamp and supporting structure for constructional vehicle, according to the embodiment of the present invention.  FIG. 6  is a side view of the lamp and supporting structure of  FIG. 5 . 
         [0040]    Referring to the drawings, the overhead lamp structure according to the embodiment of the present invention, the position controlling slits are formed on lateral sides of a bracket so that the illumination angle range of the lamp apparatus can be increased. A main case of the lamp apparatus is supported by 4 points through pluralities of hinges and the position controlling slits. In addition, a fixing screw for fixing a hinge bolt not to be rotated is provided so that the main case of the lamp apparatus supporting structure can be securely fixed to the bracket. 
         [0041]    More specifically, an overhead lamp apparatus  206  equipped with the lamp apparatus supporting structure comprises a main case  208  having a hexahedron form with an opened upper side. Additionally, the lamp apparatus comprises a plurality of LED lamps  216  mounted in the main case  208 , a PCB  214  for the lamp apparatus, being equipped with parts and sockets for operating the LED lamps  216 , a collimate lens  218  connected to a front side of the LED lamps  216  to reflect an illuminated light by a predetermined angle, and a protection board  220  formed at the front side of the collimate lens  218  to protect the LED lamps  216  from contaminants. 
         [0042]    In addition, a cover  210  covering the front of the protection board  220  is connected to the front of the main case  208 . A packing material  212  is interposed between the cover  210  and the main case  208 . 
         [0043]    The main case  208  is mounted with various parts of the lamp apparatus therein. A hinge hole  222  is formed in the center of both sides of the main case  208  to be engaged with a hinge bolt  242  formed on a front end of a hinge bolt fastening lever  240 . In addition, a fixing recess  224  for connection with a fixing bolt  250  is formed at a predetermined position on the both sides of the main case  20 , being spaced from each hinge hole  222 . Thus, a 4-point supporting system can be achieved. 
         [0044]    Additionally, a fixing unit  226  is provided to fix the main case  208  to a roof panel  4  of a heavy equipment vehicle  2 . The fixing unit  226  includes a penetration hole  232  and position controlling slits  236  respectively corresponding to the hinge hole  222  and the fixing recesses  224  of the main case  208 . 
         [0045]    A plurality of heat sinks  225  are formed on an outer surface of the main case  208  to thereby increase a contacting area with the air. The main case  208  is formed of a high-conductive material such as aluminum. The heat sinks  225  are connected to a lower surface and a rear surface of the main case  208  corresponding to a direction of the airflow. 
         [0046]    The lamp apparatus supporting structure according to the embodiment of the present invention further includes the hinge bolt fastening lever  240  for connecting the main case  208  to the fixing unit  226  in a hinged manner, and the fixing bolts  250  for fixing the main case  208  to the fixing unit  226  through the position controlling slits  236  to have a predetermined illumination angle. 
         [0047]    Here, the hinge bolt fastening lever  240  includes the hinge bolt  242  at the front end, and the hinge bolt  242  is formed with male screw threads on an outer circumference thereof. The hinge hole  222  and the fixing recess  224  of the main case  208  are formed with female screw threads on an inner circumference thereof, respectively. On the other hand, the hinge bolt fastening lever  240  and the fixing bolt  250  are formed with male screw threads on an outer circumference, respectively. 
         [0048]    The fixing unit  226  comprises a center supporter  228  fixed to the roof panel  4  of the vehicle, side supporters  230  extended upward in a vertical direction from both ends of the center supporter  228  and brought into close contact with lateral sides of the main case  208 , and position controlling ribs  234  extended rearward from upper parts of the side supporters  230  (refer to  FIG. 5 ) and each formed with the position controlling slit  236  in the center thereof. 
         [0049]    The position controlling slit  236  is formed at the main case  208  in an arc form to cope with displacement of the main case  208  pivoting with respect to the fixing recesses  224  engaged with the fixing bolts  250 . Here, the illumination angle according to a rotational range of the main case  208  through the position controlling slit  236  is ±90 degrees. 
         [0050]    More specifically, the position controlling slit  236  is cut out in the arc form around the hinge bolt fastening lever  240 , by ¼ length of a circular circumference such that the angle of the main case  208  can be controlled between the front side and the vertical lower side. Therefore, when the fixing bolt  250  is connected at the uppermost position of the position controlling slit  236 , the main case  208  illuminates the front side. When the fixing bolt  250  is connected at the lowermost position of the position controlling slit  236 , the main case  208  illuminates the vertical lower side. 
         [0051]    Especially, considering that the present invention is explaining the lamp apparatus supporting structure for the heavy equipment vehicle, the working position of the lamp apparatus supporting structure may be a front bottom surface or a front wall of the vehicle. Therefore, as the illumination angle range of the main case  208  is increased, convenience of the work is improved. 
         [0052]    In addition, the center supporter  228  further includes a connection rod  238  formed at a lower central position, having a male screw thread  238   a  on an outer circumference thereof to be fixed to the roof panel  4 , and a nut  238   b.    
         [0053]    According to the conventional lamp apparatus supporting structure for such a heavy equipment vehicle, the hinge bolt fastening lever  240  may be loosened and separated while the vehicle is running on a rough ground of the poor working environment. To this end, according to this embodiment, a connection screw  260  is provided to the side supporter  230  to prevent separation of the hinge bolt fastening lever  240  by being fitted with any one outer circumferential recess  240 A of the hinge bolt fastening lever  240 . 
         [0054]    After the main case  208  is connected using the hinge bolt fastening lever  240  in a hinged manner, the connection screw  260  is fitted with the any one outer circumferential recess  240   a  of the hinge bolt fastening lever  240  and then connected with the connection hole  230   a  formed at the side supporter  230 . In this state, the hinge bolt fastening lever  240  can be prevented from being separated. 
         [0055]    Hereinafter, the function and operation of the lamp apparatus supporting structure according to the embodiment of the present invention will be described in detail with reference to the accompanying drawings. 
         [0056]    First, to fix the lamp apparatus  206  to the roof panel  4  of the heavy equipment vehicle, the penetration hole  232  of the side supporter  230  of the fixing unit  226  is corresponded to the hinge hole  222  formed on both sides of the main case  208  and then hinge-connected using the hinge bolt fastening lever  240 . Accordingly, the main case  208  is hinged on the fixing unit  226  by the hinge bolt  242  formed at the front end of the hinge bolt fastening lever  240 , thereby enabling the main case  208  to rotate about the hinge bolt  242  of the fixing unit  226 . 
         [0057]    The hinge bolt  242  formed at the front end of the hinge bolt fastening lever  240  has male screw threads along the outer circumference thereof. In addition, the hinge bolt fastening lever  240  may further include a wrench hole  246  in the center thereof so as to be rotated by a wrench. 
         [0058]    In this state, the fixing unit  226  is connected to the upper surface of the roof panel  4  using the nut  238   b  and the connection rod  238  formed in the lower central surface of the fixing unit  226 . 
         [0059]    Therefore, the lamp apparatus  206  for the vehicle can be fixed to the roof panel  4 . In order to more securely fix the hinge bolt fastening lever  240  and prevent separation of the hinge bolt fastening lever  240 , the connection screw  260  is fitted with the any one outer circumferential recess  240   a  of the hinge bolt fastening lever  240  and the connection screw  260  is connected with the connection hole  230   a  of the side supporter  230 . 
         [0060]    The illumination angle range of the lamp apparatus  206  can be controlled by the operator. More specifically, the operator may hold an angle controlling bar  262  and rotate the main case  208  by a predetermined angle relative to the fixing unit  226 , while unfastening the fixing bolt  250  connected to the fixing recess  224  through the position controlling slit  236  while maintaining a rotatable state of the main case  208  with respect to the fixing unit  226 . Next, by fastening the fixing bolt  250  to the fixing recess  224 , the fixing bolt  250  can be securely fastened to the fixing recess  224 , passing through the position controlling slit  236 , thereby fixing the main case  208  by the predetermined angle with respect to the fixing unit  226 . 
         [0061]    In this state, since the position controlling slit  236  is in the arc form having ¼ length of a circular circumference, the main case  208  can be rotated by 90 degrees with respect to the fixing unit  226 . Accordingly, the LED lamps  216  can be freely moved within the controllable angle range, that is, between the front side and the vertical lower side. Especially in the working environment for the heavy equipment vehicle, it is more advantageous when the LED lamps  216  have a great illumination angle. In this regard, the position controlling slit  236  of this embodiment is desirable since having such a relatively long length. 
         [0062]    Therefore, when the LED lamps  216  are turned on, the LED lamps  216  can light up the front side of the heavy equipment vehicle  2  by the predetermined illumination angle. Here, according to the above-structured lamp apparatus  206 , since the position controlling rib  234  including the position controlling slit  236  is extended rearward from the side supporter  230  and provided on both sides of the fixing unit  226 , the position controlling slit  236  can be formed long enough to increase the illumination angle. 
         [0063]    Moreover, the main case  208  fixed to the fixing unit  226  through the plurality of position controlling slits  236  can be more securely fixed by the 4-point supporting system. Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.