Abstract:
The present invention includes a system and method for detecting contaminated objects, for example mail pieces, through use of a pinching device that compresses the objects, thereby possibly releasing potential contaminant-containing particles into the air in a closed chamber. Whatever particles are in the closed chamber mix with the air in the closed chamber and form cavity air, which is captured by a detection and alert mechanism.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates generally to the detection of hazardous material deposited in flat objects, and, more particularly to the detection of biological hazardous material deposited in flat mail objects or the like and the isolation of such objects for decontamination or disposal.  
           [0002]    The recent incidents of anthrax-laced letters being transported through the United States Postal Service (USPS) facilities to unsuspecting recipients has alarmed the nation and the world. Currently, the tainted letters are discovered after the recipient accepts delivery or by alert postal employees noticing white powder that could be anthrax on mail parcels, sorting and distribution equipment, or themselves. There appear to be no current security devices or procedures that are available to intercept such letters at the earliest source of introduction into the USPS system, for example at the postal sorting facility.  
           [0003]    Operating and maintaining high-speed mail handling machines is a major source of common variety dust in mail handling facilities. Experts believe that automatic mail processing systems may accidentally act as aerosolizing mechanisms. In the context of anthrax-bearing mail, mail processing devices which utilize pinch rollers or that involve high impact sorting or routing of processed mail may act to force spores from envelopes into the air. The “blow-down” of these machines in cleaning or maintenance operations also may cause anthrax spores to become aerosolized.  
           [0004]    Currently, flat objects or letters are batch processed at a postal sorting facility for routing to a final destination. Mail tubs taken from mail collection boxes are emptied into a sorting bin containing objects from other mail collection boxes. The identity of the mail collection box where each object was deposited is lost when the mail tub is emptied into a sorting bin. Further, one single contaminated object can contaminate objects from several mail collection boxes. What is needed is a system that protects objects of mail, USPS employees, employee workspaces, and ultimately mail recipients from contamination while tracing the source of the contamination.  
         SUMMARY OF THE INVENTION  
         [0005]    The present invention includes a system and method for detecting contaminated objects through use of compression. The system includes a pinching subsystem that compresses incoming objects, thereby possibly forcing particles to be released into the air within a cavity formed by a closed chamber that is operably connected to the pinching subsystem. Whatever particles are released can mix with the air in the cavity forming what is herein referred to as “cavity air”, and the cavity air is captured by a cavity air processing subsystem which is operably connected to the closed chamber. The system further includes a sealable inlet through which objects are deposited into the cavity and a hooded and sealed hamper that is operably connected to the pinching subsystem to receive objects after they have passed through the pinching subsystem.  
           [0006]    The pinching subsystem of the present invention can include any type of pinching or squeezing device, for example, a pair of juxtapositional rollers and a pinching subsystem power supply, which may be a motor, to rotate the pair of juxtapositional rollers. The juxtapositional rollers can be a left roller and a right roller, in which the left roller is substantially adjacent to the right roller, and there is optimal spacing between the left and right rollers to allow constricted passage of the objects between the rollers. The left roller and right roller rotate in opposite directions. Other roller configurations may also be acceptable within further embodiments of this invention such as, for example, a top and bottom roller.  
           [0007]    The cavity air processing subsystem receives the cavity air, subjects the cavity air to at least one test for contamination, and sets an indication of the results obtained from the test(s). A decision can be made with respect to further handling of the object(s) based on the indication. The cavity air processing subsystem can optionally include a pathogen detection subsystem that tests the cavity air for contamination and sets the indication whenever the cavity air is contaminated. A tube can optionally be inserted into the cavity to draw the cavity air from the cavity.  
           [0008]    The system may optionally include a controller capable of sequencing operations of the various components of the system including but not limited to the pinching subsystem and the cavity air processing subsystem. The controller may receive a first signal from the pathogen detection subsystem whenever the cavity air is contaminated. The first signal may optionally cause the controller to transmit the indication through a computer network connection to network receptors such as other nodes on the network. The controller may also optionally transmit a second signal to the pinching subsystem power supply to stop the pinching subsystem if the pathogen detection subsystem detects a contaminant in the cavity air.  
           [0009]    The sealable inlet of the present invention provides an opening to the closed chamber through which objects may be deposited. The sealable inlet defines a sealable inlet edge that is spanned, during operation, by a cover, for example, a slidable shutter. A first substantially airtight seal is formed between the shutter and the sealable inlet edge. When the sealable inlet is covered, there is no gas exchange between the environmental air and the cavity air within the closed chamber.  
           [0010]    The sealable inlet can also optionally accommodate an interlocking device, for example a tub, for transporting objects from another location, for example a mailbox, to the closed chamber. The tub defines an interior and has a tub rim. The tub rim is compatibly shaped with the sealable inlet edge forming a second substantially airtight seal. The tub can further include a sealable slidable tub lid covering the tub rim, forming a third substantially airtight seal. The three airtight seals substantially isolate the contents of the cavity and the contents of the tub from gas exchange with the ambient workspace and outside environment. In operation, when the objects are to be emptied from the tub to the cavity, the tub is placed inverted upon the closed chamber near the shutter. The tub is then slid against the shutter, thereby opening the shutter while at the same time sliding aside the tub&#39;s slidable lid, thereby opening the tub. After the tub lid is slid aside, the objects in the tub can fall into the cavity. After the tub is emptied, the tub is slid towards the tub lid. The shutter moves back over the sealable inlet as the tub is slid over the tub lid. When the tub is completely covered by its lid, the closed chamber will be completed covered by the shutter. During this process, exchange of air between the ambient workspace and the tub/cavity is prevented by air barrier seals around the slidable tub lid and the shutter.  
           [0011]    The system can optionally include a transport device such as a conveyor belt within the cavity. If present, the transport device can be driven by a transport power supply such as a motor. The transport device forms a path and direction of normal travel from the sealable inlet to the pinching subsystem, and conveys objects along the path and direction of normal travel. The controller may transmit a third signal to the transport power supply stopping the transport device if the pathogen detection subsystem detects a contaminant.  
           [0012]    The system can also optionally include a separator mechanism for preparing the objects for entry into the pinching subsystem, primarily for separating them from each other so that they can fit properly in the intentionally-narrow opening of the pinching subsystem.  
           [0013]    The method of the present invention for detecting contaminated objects includes the steps of accepting at least one object into a sealable inlet of a cavity, and directing the object(s) in a predetermined direction. The method further includes the steps of squeezing the object(s) by a pinching subsystem to release particles associated with the object(s) into the air in the cavity forming cavity air. The step of squeezing can optionally include the steps of moving the object(s) between two rollers, and rotating the rollers while the object(s) moves between the rollers so that the object(s) is simultaneously moved through the rollers and pinched. The method further includes the steps testing the cavity air for contamination, and providing an indication if the contents are contaminated. The method of the present invention can optionally include the steps of initiating contamination processing if the cavity air is contaminated, or resetting the indication and continuing to receive objects if cavity air is not contaminated.  
           [0014]    The method of the present invention can optionally include the steps of placing the object(s) into a tub having a tub rim, inverting the tub on top of the cavity, matably connecting the tub rim with a sealable inlet edge of the cavity, and depositing the object(s) into the cavity from the tub. The method can further optionally include the step of preparing the object(s) for entry into the pinching subsystem. The method can further optionally include the step of sequencing the directing, squeezing, and testing steps. The method can further optionally include the step of transmitting the indication through a computer network.  
           [0015]    For a better understanding of the present invention, together with other and further objects thereof, reference is made to the accompanying drawings and detailed description. The scope of the present invention is pointed out in the appended claims. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING  
       [0016]    [0016]FIG. 1 is a schematic block diagram of the system of the present invention;  
         [0017]    [0017]FIG. 2 is a pictorial view of the illustrative embodiment of the system of the present invention showing an inverted tub being unloaded and a phantom view of the inverted tub showing the inverted tub in pre-unloading position;  
         [0018]    [0018]FIG. 3A is a pictorial view of a tub of the illustrative embodiment of the present invention;  
         [0019]    [0019]FIG. 3B is a pictorial view of a shutter that is matably and slidably positioned atop the sealable inlet of the illustrative embodiment of the present invention;  
         [0020]    [0020]FIG. 3C is a pictorial view of the tub lid that is matably and slidably positioned atop the tub of the present invention;  
         [0021]    [0021]FIG. 4A is a pictorial view of the inverted tub of the illustrative embodiment of the present invention where the inverted tub is in unloading position with the shutter and tub lid slid away from the sealable inlet;  
         [0022]    [0022]FIG. 4B is a transparent pictorial view of the inverted tub and a segment of the chamber into which objects are deposited from the inverted tub, in which the inverted tub is in unloading position showing the lid stopper of the slidable tub lid and shutter push of the slidable shutter; and  
         [0023]    [0023]FIG. 5 is a flowchart of the method of the illustrative embodiment of the present invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0024]    The present invention is now described more fully hereinafter with reference to the accompanying drawings, in which the illustrative embodiment of the present invention is shown.  
         [0025]    Referring now to FIG. 1, the system  10  of the present invention includes a closed chamber  12  forming a closed chamber cavity  13 , wherein the chamber  12  has a sealable inlet  15  through which objects enter the cavity  13 . The entering objects travel path  21  in direction of travel  23  and enter a pinching or squeezing subsystem  17  which performs a compression on the entering objects. The compressed objects may emit particles that mix with the air in the cavity to form cavity air  19  that enters the cavity  13  and are drawn into cavity air processing subsystem  11 . Objects  25  exit the cavity  13  through pinching subsystem  17 . The cavity air processing subsystem  11  captures the cavity air  19  and tests it for contamination.  
         [0026]    Referring now to FIG. 2, the illustrative embodiment of the present invention includes system components cavity air processing subsystem  11 , chamber  12  forming cavity  13 , sealable inlet  15 , and pinching subsystem  17  embodied in an operational system  10  in which the objects  25  are, for example, mail pieces. In system  10 , shutter  27  slides aside and inverted tub  30 , shown in pre-unloading (dotted line  30 A) and unloading (solid line  30 ) positions, is slid into position atop sealable inlet  15 . The mail pieces in inverted tub  30  fall onto a transport means such as conventional conveyor belt  39  or conventional rollers (not shown) driven by power supply  47 . The mail pieces can be prepared for entry into the pinching subsystem  17  by a separator mechanism  37  such as conventional paddles or herringbone rollers that separate mail pieces into single pieces or small clusters of mail. In the illustrative embodiment of the present invention, the mail pieces then enter the pinching subsystem  17  that illustratively includes a chute  18  and a set of pinch rollers  45 . The pinch rollers  45  compress the mail pieces as they pass into hamper  43  which is fitted with sealable hood  41  to maintain isolation between system  10  and the outside environment. The compression of the pinch rollers  45  can release particles, and the particles can mix with air in the cavity to create cavity air  19  (as shown in FIG. 1) that remains in cavity  13  while the mail pieces drop into hamper  43 .  
         [0027]    Continuing to refer to FIG. 2, cavity air processing subsystem  11  captures cavity air  19  through tube  35 , which provides a conduit from cavity  13  into the pathogen detection subsystem  33  which can contain a conventional contaminant sensor such as BIONI or Biological Aerosol Real Time Sensors manufactured by Pacific Scientific Instruments and the Biological Aerosol Warning Systems I, PCR system developed by the assignee of this application, or any real-time sensor for airborne contaminants. When contaminated cavity air is detected, cavity air processing subsystem  11  notifies controller  51 , and controller  51  sets an indication.  
         [0028]    Continuing to refer to FIG. 2, controller  51  can be a personal computer, a programmable logic controller, or an embedded controller, among other possibilities. Controller  51  can send commands to and receive data and status from cavity air processing subsystem  11 . Controller  51  can also control conveyor belt  39  and pinching subsystem  17  by controlling power supply  47 . Controller  51  can also interface with network connection  53 , which is shown in FIG. 2 as a local area network but which can be any wired or wireless network in which electronic communications are enabled. For example, information about the origin of the contents of inverted tub  30  can be fed into controller  51  which can contain an emergency alert notification system or any other conventional or custom program. Thus, when a contaminant is detected and an indication is set, the operator and network receptors  55  listening for such indications are provided information associated with the contamination that could assist in tracking the source of the contamination. Controller  51  can also control the movement of inverted tub  30  (perhaps through a conventional actuation mechanism, not shown) so that inverted tub  30  can be remotely and automatically moved into the correct position to unload objects.  
         [0029]    Referring primarily to FIG. 3A, tub  29  of the illustrative embodiment of the present invention is shown without tub lid  31  (FIG. 3C). Tub rim  57  is shown herein with four sides, but can be any shape. In the illustrative embodiment, two sides of tub rim  57  are fitted with rim lid interfaces  63  that are herein L-shaped but can be any shape. Rim lid interfaces  63  are slidably held within both lid runner  73  (FIG. 3C) and chamber opening runner  77  (FIG. 4A). Rim lid interfaces  63  allow inverted tub  30  to be slid into unloading position atop sealable inlet  15  (FIG. 4B). Tub interior  65  holds objects that will be emptied through sealable inlet  15  into cavity  13  (FIG. 4B) when inverted tub  30  is in unloading position (FIGS. 4A,B).  
         [0030]    Referring primarily to FIG. 3B, shows shutter  27  including shutter runners  67  along two edges of shutter  27 . The shutter  27  of the illustrative embodiment is preferably slidable, but can be hinged or removable in any other way. Shutter runners  67  slidably fit within chamber opening runners  77  (FIG. 4A) allowing the shutter  27  to slide away from sealable inlet  15  (FIG. 4B) as inverted tub  30  is slid into unloading position.  
         [0031]    Referring primarily to FIG. 3C, lid underside  71  of tub lid  31  is shown with lid runners  73  into which rim lid interfaces  63  (FIG. 3A) slide to cover tub  29  (FIG. 3A). Lid chamber runners  69  slidably mate with chamber opening runners  77  (FIG. 4A). On edges where there are no lid runners, tub lid  31  is sealed against gas exchange with full coverage lid tub seals  75 .  
         [0032]    Referring primarily to FIGS.  4 A-B, the illustrative embodiment of the present invention can optionally include a specialized sealed inverted tub  30  that, when atop sealable inlet  15  having sealable inlet edge  59 , can become unsealed with respect to cavity  13  but not with respect to the environment. The inverted tub  30  can be constructed of any rigid or semi-rigid material and can be any shape. The inverted tub  30  holds mail until it is inverted and slid or placed (perhaps automatically) over the sealable inlet  15  as described in detail below. A shutter  27 , preferably slidable, retractable, sealable, and constructed of any rigid or semi-rigid material, seals the cavity  13  from the outside environment and covers the sealable inlet  15  until inverted tub  30  is inverted and moved into an unloading position. Inverted tub  30  can be positioned adjacent to the shutter  27  such that a section of the tub rim  57  (FIG. 3A) is in contact with shutter push  68 . As inverted tub  30  is moved toward shutter  27  against shutter push  68 , shutter  27  simultaneously slides away from sealable inlet  15 , thus opening sealable inlet  15  so that mail pieces from inverted tub  30  can drop into cavity  13 . While inverted tub  30  is being slid into unloading position, tub lid  31  is being held in position by lid stopper  87 . After the mail is unloaded, inverted tub  30  is slid over tub lid  31  while simultaneously shutter  27  slides back into a closed position over sealable inlet  15 , perhaps through the biasing of shutter spring  79 . Before, during, and after loading and unloading, seals against ambient air exchanged are maintained through by lid tub seal  75  and shutter seal  81 .  
         [0033]    In an alternative embodiment (not shown), the shutter  27  can remain sealed over sealable inlet  15  until the inverted tub  30  is in place over the sealable inlet  15 . In this embodiment, the shutter  27  is positioned below the tub lid  31  until the inverted tub  30  is correctly positioned above the sealable inlet  15  and locked into position creating a seal. Then the shutter  27  is moved into position to open sealable inlet  15 , tub lid  31  is moved into position to open inverted tub  30 , and the mail can drop from the inverted tub  30  into cavity  13 . After the inverted tub  30  is emptied, the shutter  27  is moved under the inverted tub  30  to close sealable inlet  15 . When inverted tub  30  is to be removed, lid  31  is moved into position to close inverted tub  30 .  
         [0034]    Referring now to FIG. 5, the method of the illustrative embodiment of the present invention includes a first step of accepting at least one object into a cavity defined by a closed chamber having a sealable inlet to the cavity (method step  501 ). The step of accepting directs the object substantially onto a travel path in a direction of travel. The method next includes the step of pinching or squeezing at least one object by a pinching subsystem and releasing particles into air within the cavity forming cavity air (method step  503 ). By this step, the object is compressed and may release particles into the cavity. Optionally, the step of pinching can further include the steps moving at least one object between juxtapositioned rollers such as a rotating left roller and a rotating right roller, where the left roller is substantially adjacent to the right roller, the left roller is sufficiently spaced from the right roller to allow constricted passage of at least one object, and the left roller rotates clockwise while the right roller rotates counterclockwise. Other roller or pinching designs may be used. For example, the juxtapositional rollers may be one on top of the other, if the object to be pinched or squeezed comes in from the side.  
         [0035]    Continuing to refer to FIG. 5, the method next includes the steps of testing the cavity air for contamination (decision step  509 ), and setting an indication if the cavity air is contaminated (method step  507 ). The method of the present invention can optionally include the step of drawing the cavity air through a tube into a pathogen detection subsystem. After the indication is set, the method of the present invention can optionally include the steps of initiating contamination processing that can include the steps of stopping the pinching subsystem and stopping the cavity air processing subsystem (method step  511 ) and notifying the operator and network of the contamination (method step  515 ). If no contamination is detected, the system can reset any indication that is set and continue receiving objects into the cavity through the sealable inlet (method step  513 ).  
         [0036]    The method of the present invention can optionally include, preceding the step of accepting at least one object into the cavity, the step of depositing from a tub through an airtight connection at least one object into the cavity. The method can further optionally include the step of conveying at least one object from the sealable inlet to the pinching subsystem substantially in the travel path and substantially in the direction of travel by use of a transport device within the cavity. The method can further optionally include the step of preparing at least one object for entry into the pinching subsystem. This step of preparing, in the illustrative embodiment, takes the form of singulating the mail piece from neighboring pieces so that the singulated piece can properly exit the cavity through the pinching subsystem.  
         [0037]    The method of the illustrative embodiment can further optionally include the steps of sequencing operations among the pinching subsystem, the transport device, and the cavity air processing subsystem, and transmitting the indication through a computer network.  
         [0038]    Although the invention has been described with respect to various embodiments, it should be realized this invention is also capable of a wide variety of further and other embodiments within the spirit and scope of the present invention.