Abstract:
A portable conveyor belt that is easy to carry by hand has been presented. It can be used for inspection of packages in outdoor locations such as at sporting events, roadside check points and other temporary locations. The conveyor belt can be quickly disassembled into smaller and lighter subsystems that are easier to carry by hand. Once transported to the desired location, it can be quickly assembled.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    A portable conveyor belt system especially suited for inspection of packages using X-rays. 
         [0002]    1. Description of the Related Art 
         [0003]    Small conveyor belts are often used for inspection of packages, for example the x-ray scanners at the airport utilize a conveyor belt on which the bags are placed. As the conveyor belt moves, the bags are transported through a tunnel or a station or an enclosure where they get exposed to x-rays. These x-rays after passing through the bag are then detected and a scanned image is generated for inspection. These conveyor belt scanners are typically five to six feet long, five feet high, two and a half feet wide, weigh eight hundred to more than fifteen hundred pounds, and are therefore too heavy and big to be carried by hand to an outdoor location like a sporting event at a stadium or for roadside checkpoint use. The currently available small x-ray scanning systems, that can be hand carried, have a small imaging area and cannot be used for continuous scanning of a large number of bags. Using these hand held systems typically takes several tens of seconds to a few minutes to scan just one bag which is too slow for scanning large number of bags at an outdoor location. Therefore it would be desirable if conveyor belt type scanners could be made that are easily portable and can be hand carried. 
         [0004]    The objects of this invention are therefore to overcome some of the above problems and are listed next. 
         [0005]    2. Objects and Advantages of the Invention 
         [0006]    It is, accordingly, an object of the invention to build a conveyor belt system that is easily portable and can be hand carried. 
         [0007]    Another object of the present invention is that it can be used with an x-ray or a radiation source and a detection system for use as an easy to carry system especially suited for scanning large number of packages at an outdoor or a temporary location. 
         [0008]    These and other objects will become apparent in the description that follows. 
       SUMMARY OF THE INVENTION 
       [0009]    In accordance with one embodiment, a portable conveyor belt is presented that is especially suited for x-ray inspection of packages. It comprises of a frame or multiple sections of a frame that can be easily assembled into a longer frame, further the frame supports a conveyor belt driven over a pair of rollers with one roller at each end of the frame. The frame is supported by easy to assemble and disassemble legs. Side panels are erected over the top of conveyor frame with an easy to attach and detach mechanisms. These side panels form side walls on the sides of the conveyor belt and above it. On top of these side panels, are mounted top panels with an easy to attach and detach mechanism. The ensemble of side and top panels form a tunnel like enclosure or an inspection station over the conveyor belt. An x-ray source, a set of detectors and associated electronics can be arranged around the tunnel and the conveyor belt to assemble an inspection system. 
         [0010]    There are several embodiments, objects and advantages to this invention that will be apparent to one skilled in the art. The accompanying figures and description herein should be considered illustrative only and not limiting or restricting the scope of invention, the scope being indicated by the claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIGS. 1A and 1B  show two different views in accordance with one embodiment. 
           [0012]      FIGS. 2A, 2B and 2C  show the assembly of the conveyor frame and conveyor belt. 
           [0013]      FIG. 3  shows the assembly of the inspection tunnel over the conveyor frame. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0014]    In describing the preferred embodiment and its alternatives, specific terminology will be used for the sake of clarity. However, the invention is not limited to the specific terms so used, and it should be understood that each specific term includes all its technical equivalents which operate in a similar manner to accomplish similar purpose. 
         [0015]    A simplified assembly of one embodiment is shown in two different views in  FIGS. 1A and 1B . A conveyor belt  10  is shown driven over a first roller  11  and a second roller  12  supported by a conveyor frame comprising of two sections  5  and  6 . Section  5  of conveyor frame comprises of side rails  13  and  14  and supports the roller  11 , the section end supporting roller  11  is hereafter referred to as the first end of the conveyor frame. Section  6  of conveyor frame comprises of side rails  15  and  16  and supports the roller  12 , and the section end supporting roller  12  is hereafter referred to as the second end of the conveyor frame. Side rails  13  and  15  constitute the first side or the right side of conveyor frame and rails  14  and  16  constitute the second side or the left side of conveyor frame. The two sections  5  and  6  of conveyor frame are held in place by a securing means on either side of the conveyor frame. This securing means comprises of a sliding bolt type of a mechanism comprising of sliding member  19  and brackets  18 . The conveyor frame is supported by legs  20  that can be secured into holding brackets  25  on the side rails  13 ,  14 ,  15  and  16 . 
         [0016]    Removable right side panels  31  and  32  having top and bottom ends or sides and hereafter referred to as the right side panels are assembled adjacent to the right side of conveyor frame. 
         [0017]    The bottom sides of panels  31  and  32  are secured to side rails  13  and  15  by a means that allows quick attachment and detachment. Removable left side panels  35  and  36  having top and bottom ends or sides and hereafter referred to as the left side panels are assembled adjacent to the left side of conveyor frame. The bottom sides of panels  35  and  36  are secured to side rails  14  and  16  by a means that allows quick attachment and detachment. 
         [0018]    Removable top side panels  33  and  34  are positioned over side panels  31 ,  32 ,  35  and  36  as shown in  FIGS. 1A and 1B . Removable top side panel  33  has a left side positioned adjacent to top side of left panel  35 , and it further has a right side that is positioned adjacent to the top side of right side panel  31 . Likewise, removable top side panel  34  has a left side positioned adjacent to top side of left panel  36 , and it further has a right side that is positioned adjacent to the top side of right side panel  32 . Top panel  33  is secured by a means that allows quick attachment and detachment to the top sides of panels  35  and  31 . Likewise, Top panel  34  is secured by a means that allows quick attachment and detachment to the top sides of panels  32  and  36 . 
         [0019]    The assembly or the ensemble of side and top panels form a tunnel like enclosure or an inspection tunnel or an inspection station over the conveyor belt. The assembly of the panels is such that there is a small gap of the order of one inch or less between side panels  31  and  32 , and between top panels  33  and  34 , and between side panels  35  and  36 . This gap allows for the passage of a radiation beam  52  emitted from a radiation source or the focal point  51  of an x-ray tube situated inside a generator box  50 . The radiation beam  52  intersects the volume or space or the inspection tunnel enclosed by the side panels, the top panels and the conveyor belt  10 . This radiation beam is detected by a detector comprising of detector boxes  40  and  41 . The radiation beam  52  passing through the gap between top panels  33  and  34  hits the top detector box  40 . 
         [0020]    Likewise, the radiation beam  52  passes through the gap between side panels  35  and  36  hits the side detector box  41 . The radiation or signal detected by detector boxes  40  and  41  is converted to electronic signal that is processed by electronics means and displayed on a screen as a scanned image. The panels  33 ,  34 ,  35  and  36  are usually lined with lead to contain the x-ray radiation within the inspection tunnel formed within the space enclosed by these panels. Various other electronic and mechanical details of the system have been omitted to avoid the clutter but well understood by a person skilled in the art. 
         [0021]    The conveyor system as described above allows for breaking down or disassembly of a larger and heavier system into smaller subsystems or parts that are easier to transport and can be hand carried. These smaller subsystems and their assembly is further illustrated in  FIGS. 2A, 2B and 2C . 
         [0022]      FIG. 2A  shows the two sections  5  and  6  of the conveyor frame brought close together and ready to be assembled.  21  and  22  are rigid panels that separate the side rails of section  5  and  6  respectively. They comprise the bed or the top side of the conveyor frame over which the conveyor belt  10  slides. The side opposite the top side of conveyor frame is hereafter referred to as the underside. Next the two sections  5  and  6  are arranged as shown in  FIG. 2B  and the conveyor belt  10  is slipped over them. The two sections  5  and  6  are then pulled apart in the direction indicated by arrows  60  shown in  FIG. 2B . As the two sections  5  and  6  are pulled apart, they are aligned and secured together by sliding member  19  into brackets  18  as shown in  FIG. 2C . As a result of above assembly of the two sections  5  and  6 , the conveyor belt  10  gets stretched tight over rollers  11  and  12 . In the assembly of  FIG. 2C  is shown a gap  23  indicated by dotted lines, this gap is between panels  21  and  22  and is covered over by the belt  10 . This gap  23  allows the radiation beam  52  to pass vertically from below the belt  10  to above it. Also shown in  FIG. 2C  is a notch  24  that is a small gap between the top end of rails  13  and  15 , it allows the radiation beam  52  to impinge the belt  10  from below and to the side of it as shown in  FIGS. 1A and 1B . 
         [0023]      FIG. 3  shows the exploded view of panels  31  through  36  and detector boxes  40  and  41 . 
         [0024]    The system as described above can be easily disassembled into smaller subsystems or parts that can be easily carried and reassembled at the destination location. 
         [0025]    In an alternative embodiment, the legs  20  can be long and the x-ray generator  50  can be placed under the conveyor frame and oriented such that the x-ray beam  52  passes through the gap  23  between sections  5  and  6  shown in  FIG. 3 . The beam  52  after passing through the gap then hits or impinges upon the detector boxes  40  and  41 . Further, the detector boxes  40  and  41  could be positioned inside of the tunnel space enclosed by the side and top panels. In such a case, side panels  35  and  36  could be combined into one left side panel; side panels  31  and  32  could be combined into one right side panel; and top panels  33  and  34  could be combined into one top panel. 
         [0026]    The side panels  31 - 36  are shown placed over side rails  13 - 16  in  FIGS. 1A and 1B . However, these side panels could instead be vertically positioned by suitable means on to the ground and to the out sides of the conveyor frame. 
         [0027]    The purpose of the inspection tunnel comprising of panels  31 - 36  is to contain the radiation from spreading outwards and possibly irradiating any humans around. However, for remote operations when there are no humans around at the time x-rays are turned on, then it is not necessary to assemble panels  31 - 36 . 
         [0028]    In yet another embodiment, there are no panels  31  through  36  and no detector boxes  40  and  41 . Instead the x-ray box  50  includes a back scatter mechanism with a detector that detects the backscattered x-rays to analyze the composition of the package that is placed over the belt  10 . 
         [0029]    In yet other alternative embodiments, the x-ray source  50  may be replaced by radioactive source, or an electromagnetic source, or a laser or another optical source to interrogate the package. 
         [0030]    In yet another embodiment, the box  50  may contain a sniffer which analyzes the air or vapor molecules coming off the surface of package to determine if the contents of the package are explosives or some contraband. 
         [0031]    In yet another embodiment, the conveyor system of  FIG. 2C  may not be used for inspection of packages, but just to build a longer conveyor system comprising of multiple smaller sections. 
         [0032]    In yet another alternative embodiment, the conveyor of  FIG. 2C  may comprise of just one section instead of two sections  5  and  6 . Alternatively, there may be more than two sections comprising the conveyor frame. 
         [0033]    There are several embodiments possible as would be apparent to a person skilled in the art. 
         [0034]    The foregoing description of the invention and its embodiments should be considered as illustrative only of the concept and principles of the invention. The invention may be configured in a variety of ways, shapes and sizes and is not limited to the description above. Numerous applications of the present invention will readily occur to those skilled in the art. Therefore, it is desired that the scope of the present invention not be limited by the description above but by the claims presented herein.