Abstract:
A combination dock light and bollard serves the purposes of both, without having any sensitive structure projecting out from the bollard into the traffic lane at the loading dock. A lamp assembly within the bollard projects out a window cutout at an upper end of the tubular metal body of the bollard. The lamp assembly rests on a sub-plate welded into the bollard below the cutout. The lamp holder is mounted on compression springs held in place with machine screw, to permit adjustment of the lamp beam direction. A photo eye turns the lamp on when the loading dock door is opened, and off when the dock door is closed.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims priority under 35 U.S.C. §119(e) of U.S. Provisional Pat. Application No. 61/091,742, filed Aug. 26, 2008, which is incorporated by reference herein. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    This invention relates to loading dock lighting systems, of the type intended to shine light inside a tractor trailer, van, railroad car, etc., when present at a loading dock at a warehouse or other shipping or receiving location. Loading vehicles, such as fork lifts and pallet lifters, are used in bringing goods and materials into a trailer or out of a trailer when the same is stationed at a loading dock. In order to help provide enough light for the fork lift operator during loading or unloading, it is often necessary to use a dock light. These items typically project from some structure, such as the edges or vertical guides of the dock door or gate, or can sometimes be installed on a post or bollard at the loading dock gate. One example of this is discussed in U.S. Pat. No. 7,101,064. These dock lights project out from the doorway or from the side of the bollard into the lanes that are traversed by the fork lifts or other equipment, and thus they are subject to collision damage. The docking equipment industry is aware of this problem, but has been unable to address it. 
       OBJECTS AND SUMMARY OF THE INVENTION 
       [0003]    Accordingly, it is an object of the present invention to provide a dock light system that avoids the drawbacks of the prior art. 
         [0004]    It is another object to provide a combination dock light and bollard that serves the purposes of both, without having any sensitive structure projecting out from the bollard into the fork lift traffic lane at the loading dock. 
         [0005]    It is a more specific object to provide an illuminated bollard which is of simple construction, with clean lines and capable of providing good visibility into the interior of the truck or van being loaded or unloaded. 
         [0006]    In accordance with one aspect of the present invention, an illuminated bollard is adapted to be installed adjacent a loading dock door and to provide illumination into a truck body or trailer positioned at the loading dock door and distally thereof. The illuminated bollard has a vertical tubular metal body (typically cylindrical, but possibly of other shapes); and a base plate that serves as a means for affixing the tubular metal body of the bollard to a horizontal floor surface. A window cutout is formed at an upper end of said bollard tubular metal body on a distal-facing side thereof (i.e., on the side looking out the dock door into the truck body or trailer). A fixed sub-plate is welded onto the inner surface of the tubular metal body below the window cutout, and a lamp assembly is seated on the sub-plate inside the upper end of bollard tubular metal body. The sub-plate can be in the form of a flange on the inner wall of the bollard tubular body, projecting radially inward a short distance and leaving an open core for electrical connections to conductors within the bollard. 
         [0007]    The lamp assembly is made up of (a) a base plate adapted to rest upon the sub-plate; (b) a directional lamp supported on the base plate to provide a beam of light oriented generally horizontally and in the distal direction through the bollard window cutout; (c) an automatic sensor switch, such as an optical light switch, adapted to switch the lamp on when the loading dock door is opened and to switch the lamp off when the loading dock door is closed; and (d) a power supply that provides electrical power to the lamp. The directional lamp and optical light switch can be mounted onto, or above, the lamp assembly base plate. The directional lamp can include a lamp holder supported on compression springs held in place by long machine screws that pass through the holder and springs and into the base plate. The lamp holder is positioned so as to hold the lamp in a horizontal orientation, but also permit vertical adjustment of the lamp beam direction, and also permit some left to right adjustment of the lamp beam direction. 
         [0008]    In a preferred mode, the illuminated bollard can have a plastic protective sleeve fitted over its tubular metal body, and the plastic sleeve has a window cutout therein aligned with the window cutout of the tubular metal body. Light from reflected from internal surfaces of the bollard illuminates the top of the sleeve, to increase visibility of the bollard. 
         [0009]    Preferably, the sensor switch can be an optical switch, such as a photo eye unit operative to detect light (e.g., infrared) reflected from the loading dock door when the door is closed. To assist detection of reflected light, a strip of reflective tape can optionally be positioned on the dock door so that it is in alignment with the photo eye unit when the door is in its closed position. 
         [0010]    The lens holder is supported on springs above the base plate, and these springs act to absorb some of the shock of collision with the fork lift or loading equipment and protect the lamp from damage. 
         [0011]    An acoustic sensor, such as an ultrasonic or sonic detector, may be used rather than the optical switch to detect the presence of the door surface when the loading dock door is down or closed and to turn the dock light assembly on and off. A mechanical sensor, such as a microswitch with a wire whisker, may be used in some applications. 
         [0012]    A metal mesh screen is positioned in the bollard window cutout to protect the lamp assembly. 
         [0013]    The illuminated bollard may be present on one side only or on both sides of the loading dock door, as needed. 
         [0014]    The above and many other objects, features, and advantages of this invention will be more fully appreciated from the ensuing description of a preferred embodiment, which is to be read in conjunction with the accompanying Drawing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0015]      FIG. 1  is a perspective view of loading dock, employing an illuminated bollard according to one embodiment of the present invention. 
           [0016]      FIG. 2  is a front perspective view of the lamp assembly of this embodiment. 
           [0017]      FIG. 3  is an assembly view of the illuminated bollard of this embodiment. 
           [0018]      FIG. 4A  is a perspective view of the lamp assembly. 
           [0019]      FIG. 4B  is an assembly view of the lamp assembly of this embodiment. 
           [0020]      FIG. 5  is a perspective cutaway view of the top of the bollard tubular metal body. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0021]    With reference now to the Drawing,  FIG. 1  shows the interior of a loading dock area of a warehouse or other shipping or receiving area, with a floor  10 , wall surface  12 , and a dock door  14 . The dock door slides up and down in vertical door guides  18  at its left and right sides. The dock door  14  is opened, by lifting it upwards, to access the interior of a truck body, van, or trailer that has been parked or spotted at the dock gate. 
         [0022]    A bollard  20 , i.e., a strong steel post, is affixed to the dock floor  10  just in front of the door guide  18  to protect the door and guide from accidental bumping by a fork lift or other loading equipment as it goes through the open dock door  14  into and out of the truck that is being loaded or unloaded. Typically, there is a bollard at each side of the loading dock gate, but only one is shown here for purposes of simplicity. One of the two bollards is illuminated, and the other is of the standard type. The bollards can be cylindrical or pipe bollards, although other shapes could be used. 
         [0023]    This bollard  20  is an illuminated bollard, with a lamp device or assembly within it, and which projects its light in the distal direction, through a window cutout or opening  22  on the distal side of the bollard, at or near the top thereof. Here, the window cutout  22  and the internal lamp assembly are about forty inches (e.g., 100 cm) above the floor or deck of the dock area. A mounting plate  24  is shown here at the base of the bollard  20  for permanently mounting the same to the floor. Depending on the lighting conditions inside the warehouse, and also depending upon the sensitivity of the equipment as discussed below, reflective tape may be applied to the dock door. 
         [0024]    As shown in more detail in  FIG. 2 , the bollard  20  is in the form of a tubular cylindrical body  25 , i.e., a metal pipe, with the window cutout  22  formed as a generally rectangular opening near the top end. As seen in  FIG. 3  a support gusset  26  on the distal side of the tubular body  25  is affixed to the body  25  and to the mounting plate  24 . Also, a protective plastic sleeve or cover  28  fits over the body  25 , and this cover has a matching opening  29  that aligns with the bollard window opening  22 . A rectangular opening  27  in the tubular body  25  below the window cutout  22  serves as a window for an infrared optical door sensor, to be discussed shortly, and there is a rectangular cutout  30  in the sleeve  28  that aligns with the rectangular opening  27  of the tubular metal body. There is a vertical slot  31 , i.e, a keyway member that fits over the gusset  26 , and serves to align the position of the sleeve  28  on the metal body  25 , such that when the sleeve  28  is installed over the bollard body  25 , that the two circular cutout  29  aligns with the window opening  22 , and the rectangular cutout  30  aligns with the opening  27 . 
         [0025]    An electrical cord  32  emerges from the base of the bollard, as shown here, and can be plugged into a conventional power outlet. Alternatively, the bollard can be direct-wired. 
         [0026]    A mesh screen  33  is affixed into the window  22  and serves to protect the lamp assembly  40  within the bollard  20  (the lamp assembly  40  is visible through the window  22  and screen  33  in  FIG. 2 ). The screen  33  reflects some of the light produced from the lamp assembly, and this reflected light illuminates the top part of the sleeve, which is made of a translucent plastic material. This increases the visibility of the bollard when the lamp assembly is on. The mesh screen is omitted from the view in  FIG. 5 , but can be understood to be welded or attached with fasteners on the inner side of the window opening  22 . A similar screen may be employed at the photo switch opening  27 , if desired. In some possible embodiments, the screen or screens may be incorporated into the sleeve  24 . 
         [0027]    The lamp assembly  40  can be removably installed through an open top of the tubular metal body  25 . A base plate  42  of the light assembly  40  rests upon a sub-base  44  that is affixed horizontally to the inside surface of the tubular metal body  25  just below the lower edge of the opening  27 . As shown in  FIG. 5 , this sub-base can be in the form of a flange that projects inward a short distance from the wall of the bollard tubular body  25 , so as to leave an open central region. 
         [0028]    On the light assembly as shown in exploded assembly view in  FIG. 4B , and in perspective of  FIG. 4A , a directional lamp  46 , i.e., a reflector light or flood light, is held on a lamp holder  48  that is mounted above the lamp assembly base plate  42 . A power supply  40  is mounted onto the lower side of the base plate  42 . An electric eye or photo switch  54  uses visible light or other radiation that is reflected from the door  14 , and which passes back through the bollard cutout  27 , to turn the lamp  46  on when it detects that the door  14  has been lifted open, and to shut the lamp  46  off when it detects that the dock door  14  has been closed. 
         [0029]    The lamp holder  42  has a base member that is supported on compression springs  56 , which are held in place with long machine screws  58  or equivalent threaded members, which pass through openings in the lamp holder  42 , then through the springs  56  and into threaded openings in the base plate  42 . There is an elongated, generally bow-shaped screw opening  59  at the back end of the lamp holder  42 , and this allows some lateral movement of the back of the lamp holder, so that the lamp beam direction can be adjusted from left to right. The screws  58  can be adjusted up or down to change the vertical direction of the lamp beam, as well. Thus, the arrangement as shown here with the springs  56  and machine screws  58  allows for both lateral (left to right) and vertical (up and down) adjustment of the direction of the beam of the lamp  46 . The springs also serve to cushion the lamp holder  46  against shocks in the event that a forklift or other vehicle collides with the bollard  20 . In some embodiments, rubber grommets or cushions can be positioned to absorb the shock of collision to protect the lamp assembly. 
         [0030]    The lamp assembly  40  can dropped into place on top of the fixed sub-base  44 , as shown in  FIG. 5 , with the lamp  38  oriented to shine in a generally horizontal and distal direction, out through the bollard window cutout  22 . The entire assembly is removable for repair or replacement, leaving the sub-base  44 . A standard electrical connector (not shown here) may be used for quick connect and disconnect of the power supply  50  with the power conductors within the bollard tubular body  25 . 
         [0031]    As mentioned before, the bollard  20  can have a different profile, e.g., square or oblong, and the door open-close detection can be carried out by means other than the electric eye switch. The bollard lamp window cutout or opening  22  is round in this embodiment, but could just as well be another shape. In this embodiment there are separate cutouts  22  and  27  for the lamp and the photo switch, but in some embodiments, the two could use a common cutout or opening. 
         [0032]    While the invention has been described with reference to specific preferred embodiments, the invention is certainly not limited to those precise embodiments. Rather, many modifications and variations will become apparent to persons of skill in the art without departure from the scope and spirit of this invention, as defined in the appended claims.