Abstract:
For a radiation imaging inspection system, apparatus, and/or method, the system, particularly a trailer security inspection system, may include a protective wall forming an inspection passage for passage of a trailer, a radiation imaging system effecting security inspection of the trailer passing through the inspection passage, and a traction arrangement for hauling the trailer.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a radiation imaging inspection system, particularly to a trailer security inspection system. 
       BACKGROUND INFORMATION 
       [0002]    A trailer (or connected cars) is used to haul luggage and goods at the Customs House, airports, or railway stations. The trailer can include a tractor as a motive power source and a plurality of flatcars or compartments hooked together in series hauled by the tractor. Radiation imaging inspection is often a requisite inspection means for the Customs House, airports and railway stations. The radiation imaging inspection refers to an inspection performed via an inspection passage including shielding rays, a radiation source, and an array detector which can receive the rays having permeated an inspected vehicle, where the inspected vehicle is hauled by a special traction means through the radiation beam for inspection. The inspection system usually comprises an accelerator system, a detector system, an image data acquisition system, a scanning device, and an operation &amp; inspection system. In the prior technology, there are X-ray inspection devices for inspecting a passenger&#39;s luggage, and special inspection apparatuses for inspecting freight vehicles or container trucks. At present, there is not an inspection apparatus specially for inspecting a trailer. 
       SUMMARY OF THE INVENTION 
       [0003]    An object of the present invention is to overcome the drawbacks of the above prior technology and to provide a trailer security inspection system for inspecting goods loaded on a trailer by using a radiation imaging principle under the condition that the case containing the goods is not opened. 
         [0004]    To achieve the above object, an example embodiment of the present invention adopts the following technical solution. The trailer security inspection system according to an example embodiment of the present invention comprises a protective wall forming an inspection passage for passage of the trailer, a radiation imaging system effecting security inspection of the trailer passing through said inspection passage, and a traction arrangement for hauling the trailer. 
         [0005]    Furthermore, in an example embodiment, said trailer security inspection system further comprises an accelerator cabin for mounting an accelerator of said radiation imaging system and a horizontal detector arm and a vertical detector arm for mounting detector modules of said radiation imaging system, where one end of the horizontal detector arm is connected to a top of the accelerator cabin, and the other end thereof is connected to an upper end of the vertical detector arm. 
         [0006]    Furthermore, a window of the horizontal detector arm from which detector modules in the horizontal detector arm are accessible may open downwardly and is preferably covered by a horizontal door, and a window of the vertical detector arm from which detector modules in the vertical detector arm are accessible may open towards an inner side of the passage and is preferably covered by a vertical door. 
         [0007]    Further, in an example embodiment, the protective wall comprises four sections: a first protective wall, a second protective wall, a third protective wall, and a fourth protective wall. In the example embodiment, the first protective wall and the second protective wall are respectively connected to both sides of the vertical detector arm along one side of said inspection passage, and the third protective wall and the fourth protective wall are respectively connected to both sides of the accelerator cabin along another opposite side of the inspection passage. 
         [0008]    Furthermore, the traction arrangement preferably comprises a rotatable traction arm. 
         [0009]    Furthermore, in an example embodiment, the traction arrangement further comprises a machine base, a guide rail mounted on the machine base, a slide cooperating with the guide rail, and a drive arrangement driving the slide to move along the guide rail. In the example embodiment, the traction arm is rotatably connected to the slide via a rotation shaft. 
         [0010]    In an example embodiment, the drive arrangement comprises a positive and reverse rotatable decelerating motor mounted on the machine base and its transmission mechanism, the transmission mechanism comprises two chain wheels and a chain cooperating with the two chain wheels, one of the two chain wheels is coupled to an output shaft of the motor, and the slide is connected to the chain. 
         [0011]    Furthermore, in the example embodiment, on the slide are mounted a first stop and a second stop limiting the rotation scope of the traction arm, an automatic arm expanding mechanism urging said traction arm to rotate, and a locking arrangement for locking the traction arm. 
         [0012]    Furthermore, the automatic arm expanding mechanism may comprise an arm expanding stop mounted on one end of the machine base and an arm expanding pin mounted on the traction arm. The arm expanding stop is provided with a side plane for cooperation with the rotation shaft and a front inclined plane for cooperation with the arm expanding pin. 
         [0013]    Furthermore, the locking arrangement may comprise a rotatable block rotatably connected on the slide, and a spring. The ends of the spring may be respectively hooked on one end of the rotatable block and the slide. A locking pin may be provided on one side of the rotatable block adjacent to the spring. The traction arm may be provided with a groove cooperating with the locking pin. 
         [0014]    In an example embodiment, an unlocking pressing block is provided on the end of the machine base opposite to the arm expanding stop. 
         [0015]    Furthermore, preferable, the rotatable block is a diamond-shaped block, the rotation shaft being located at a central position thereof, and the unlocking pressing block has an inclined surface cooperating with an outer surface of the diamond-shaped block. 
         [0016]    Furthermore, said groove is preferably a right-angle groove. 
         [0017]    Advantages and positive effects of the trailer security inspection system according to the present invention include that the system comprises protective walls, a radiation imaging system, a horizontal detector arm, a vertical detector arm, and a traction arrangement for hauling the trailer, and that the system is a special apparatus suitable for inspecting a trailer, provides a reliable technical method for conducting a security inspection of luggage, and is adaptable and economical to a large extent. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]      FIG. 1  is a schematic view showing the structure of a trailer security inspection system according to an example embodiment of the present invention. 
           [0019]      FIG. 2  is a cross sectional view taken along the line A-A of  FIG. 1 , showing the planar arrangement of an example embodiment of the present invention. 
           [0020]      FIG. 3  is a cross sectional view taken along the line B-B of  FIG. 1 , showing the basic structure of a horizontal detector arm according to an example embodiment of the present invention. 
           [0021]      FIG. 4  is an enlarged view of portion D of  FIG. 2 , showing the basic structure of a vertical detector arm according to an example embodiment of the present invention. 
           [0022]      FIG. 5  is a top view of a traction arrangement according to an example embodiment of the present invention. 
           [0023]      FIG. 6  is a front view of the traction arrangement according to an example embodiment of the present invention. 
           [0024]      FIG. 7  is a side view of the traction arrangement according to an example embodiment of the present invention. 
           [0025]      FIG. 8  is a schematic view showing an initial position of a traction arm during automatic deployment, according to an example embodiment of the present invention. 
           [0026]      FIG. 9  is a schematic view showing an intermediate position of the traction arm during automatic deployment, according to an example embodiment of the present invention. 
           [0027]      FIG. 10  is a schematic view showing a finished position of the traction arm during automatic deployment, according to an example embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0028]    In the figures, the reference numeral designations are as follows.  1  designates an accelerator cabin;  2  designates an accelerator;  3  designates a horizontal detector arm;  4  designates a detector module;  5  designates a collimator;  6  designates a vertical detector arm;  7  designates a traction arrangement;  8  designates a traction arm;  9  designates a traction hook;  10  and  11  each designates a door;  12  designates a trailer;  13  designates a first protective wall;  14  designates a third protective wall;  15  designates an electrical control cabinet;  16  designates a modulator;  17  designates a fourth protective wall;  18  designates a second protective wall;  19  designates an arm expanding stop;  20  designates an arm expanding pin;  31  designates a machine base;  32  designates a decelerating motor;  33  designates a bearing bracket;  34  designates a chain wheel;  35  designates a chain;  36  designates a guide rail;  37  designates a slide;  38  designates a tensioning bolt;  39  designates a rotation shaft;  41  designates a first stop;  42  designates a second stop;  44  designates a locking pin;  45  designates a connecting shaft;  46  designates a rotatable block;  47  designates a spring; and  48  designates a unlocking pressing block. 
         [0029]    The following embodiments are used to illustrate the present invention and not to limit the scope of the present invention. 
         [0030]    As shown in  FIGS. 1 to 4 , the trailer security inspection system according to the present invention comprises an accelerator cabin  1  for mounting a radiation imaging system, a protective wall for forming an inspection passage, a horizontal detector arm  3 , a vertical detector arm  6 , and a traction arrangement for dragging the trailer. 
         [0031]    The protective wall comprises four sections: a first protective wall  13 , a second protective wall  18 , a third protective wall  14  and a fourth protective wall  17 . The first protective wall  13  and the second protective wall  18  are respectively connected to the vertical detector arm  6 , and the third protective wall  14  and the fourth protective wall  17  are respectively connected to both sides of the accelerator cabin  1 . The connection modes of the protective walls to the accelerator cabin  1  and the vertical detector arm  6  omit use of members such as a support rod for supporting the protective wall so that the structure of the system according to the present invention is simple and compact. Certainly, a support member can also be used to mount the protective walls. 
         [0032]    One end of the horizontal detector arm  3  is connected to a top of the accelerator cabin, and the other end thereof is connected to the vertical detector arm  6  so that the horizontal detector arm  3  and the vertical detector arm  6  are in an L shape (a person skilled in the art can recognize that the horizontal detector arm  3  and the vertical detector arm  6 , as shown in  FIG. 1 , are in fact formed in an inverted L shape which is however generally called L shape). A plurality of detector modules  4  are respectively mounted in the horizontal detector arm  3  and the vertical detector arm  6 . A window of the detector module  4  in the horizontal detector arm  3  opens downwardly so that both sides of the horizontal detector appear pleasant. Further, opening downwardly can provide a very good water-resistant effect. A horizontal door  10  is closed to cover the window. A window of the detector module  4  in the vertical detector arm  6  opens towards the inner side of the passage and a vertical door  11  is closed to cover the window. 
         [0033]    In the accelerator cabin  1  are mounted an accelerator  2  for generating X-rays with a certain energy and dosage, a collimator  5  for controlling a width of a beam of X rays generated by the accelerator and radiated on a receiving surface of the detector, a modulator  16  for controlling energy and dosage outputted by the accelerator, and an electric control cabinet  15  in which components of a control system are mounted to allow for normal operation of the whole set of the apparatus. 
         [0034]    A traction arrangement  7  is mounted at a lower corner of the side adjacent to the accelerator cabin  1  and does not occupy the dimension of the scanning passage. 
         [0035]    As shown in  FIGS. 5-7 , the traction arrangement  7  of the present invention comprises a machine base  31 , a drive arrangement mounted on the machine base  31 , and a traction arm  8 . 
         [0036]    The machine base  31  is rectangular parallelepiped, and a guide rail  36  is mounted in a longitudinal direction of its side. A slide  37  is provided on the guide rail  36 . The traction arm  8  is connected to the slide  37  via a rotation shaft  39 . The slide  37  is provided with a first stop  41 , a second stop  42 , and a locking arrangement. The first stop  41  and the second stop  42  are used to limit the scope of angle of rotation of the traction arm  8 . In the illustrated embodiment, the traction arm  8  can rotate 90° about the rotation shaft  39 . A traction hook  9  is mounted at the other end of the traction arm  8  and used to connect the inspected vehicle. 
         [0037]    The locking arrangement of the example embodiment of the present invention comprises a rotatable block  46 , a spring  47 , and a locking pin  44 . The rotatable block  46  is a diamond-shaped block and is connected to the slide  37  at a central position thereof via a connecting shaft  45 . The ends of the spring  47  are respectively hooked on one end of the rotatable block  46  and the slide  37 . The locking pin  44  is provided on the side of the rotatable block  46  adjacent to the spring  47 . The traction arm  8  is provided with a right-angle groove. The groove can be an acute angle or a blunt angle. When the locking pin  44  is in the right-angle groove, the locking arrangement is in a locked state and the traction arm  8  cannot rotate relative to the slide  37 . When the locking pin  44  is in a disengaged state from the right-angle groove, the locking arrangement is in an unlocked state and the traction arm  8  can rotate relative to the slide  37 . 
         [0038]    In the present invention, the unlocking action of the locking arrangement can be realized by an unlocking pressing block  48 . The unlocking pressing block  48  is fixed on the machine base  31  at a distal end of the travel of the slide  37 . The unlocking pressing block  48  is provided with an inclined surface cooperating with the outer surface of the rotatable block  46 . When the unlocking pressing block  48  is in contact and cooperation with the rotatable block  46 , the rotatable block  46  is forced to rotate about its central shaft  45  so that the locking pin  44  on the rotatable block  46  is disengaged from the right-angle groove on the traction arm  8  so that the traction arm  8  is in a unlocked state. 
         [0039]    As shown in  FIGS. 8-10 , the expansion of the automatic arm expanding mechanism according to an example embodiment of the present invention is as follows: the automatic expansion of the traction arm  8  is realized by the interaction of an arm expanding stop  19  and an arm expanding pin  20 , wherein the arm expanding stop  19  is fixed on the machine base  31 , the arm expanding pin  20  is fixed on the traction arm  8 , and the arm expanding stop  19  is provided with a side plane for cooperation with the rotation shaft  39  and a front inclined surface for cooperation with the arm expanding pin  20 . When the slide  37  returns to an initial position and before the slide  37  stops, and after the arm expanding stop  19  contacts the arm expanding pin  20 , the arm expanding stop  19  blocks further forward movement of the arm expanding pin  20  to urge the traction arm  8  to rotate about the rotation shaft  39 . As the slide  37  continues to move forward, the traction arm  8  gradually automatically expands and stops to be perpendicular to the movement direction. 
         [0040]    The drive arrangement of the present invention comprises a positive and reverse rotatable decelerating motor  32  mounted on the machine base  31  and its transmission mechanism. The transmission mechanism comprises two chain wheels  34  mounted on both ends of the machine base  31 , a chain  35  cooperating with the two chain wheels  34 , where one of the two chain wheels is coupled to an output shaft of the motor and where the slide  37  is connected to the chain  35 . The tensioning of the chain is effected by a tensioning bolt  38 . The tensioning bolt  38  is mounted between the machine base  31  and the bearing bracket  33 . The transmission mechanism is not limited to said structure of the embodiment, and other transmission mechanisms such as a gear-rack transmission mechanism or a steel wire cable hoisting transmission mechanism are also adaptable for the present invention. 
         [0041]    A working procedure of the trailer security inspection system according to an example embodiment of the present invention. (1) The traction arm  8  of the traction arrangement is in place at the entrance to the scanning passage, whereupon the traction arm  8  expands to be perpendicular to the scanning movement direction. (2) An operator pulls an inspected trailer  12  to the entrance of the scanning passage and hooks the trailer  12  to the traction hook  9 . (3) The motor  32  of the traction arrangement is activated, the chain conveyance system works, the slide  37  moves forward under the traction of the chain  35 , whereby the traction arm  8  pulls the trailer being inspected through the scanning passage at a predetermined speed. (4) After the traction arrangement pulls the trailer to a prescribed position, the accelerator  2  sends out a beam to scan. On completion of the inspection, the trailer being inspected is pulled to an unloading position. Before the stop of the trailer, the inclined surface of the unlocking pressing block  48  is in contact and cooperation with the inclined surface of the rotatable block  46  so that the rotatable block  46  rotates about the connecting shaft  45 , whereby the locking pin  44  is disengaged from the right-angle groove on the traction arm  8  to open the traction arm  8 , whereupon the traction arm  8 , due to an external force, can rotate forwardly 90°. (5) When the trailer stops, the operator separates the trailer  12  from the traction arm  8  and rotates the traction arm  8  forwardly a certain angle to pull the trailer  12  away from the scanning region. (6) Then the operation starts a return signal to allow the traction arm  8  to return to the starting position. (7) When the traction arm  8  moves to the starting position, the traction arm  8 , under the action of the arm expanding stop  19 , stops after automatically expanding 90°, whereupon the traction arm  8  gets prepared for a next cycle. (8) The operator can pull next trailer  12  to the entrance to the scanning passage for the upcoming inspection.