Baggage screening system and method

A baggage screening system and method includes providing a plurality of screening subsystems, each including an automated baggage screen device and a feed conveyor for feeding bags to the screen device. A supply conveyor is provided for supplying bags to the screen subsystems. A sortation network sorts bags downstream of the screen device as a function of the screening of the bags.

BACKGROUND OF INVENTION

The present invention is directed to a baggage screening system and method and, in particular, to an automated system utilizing automatic baggage screen device(s). The present invention is particularly useful for screening baggage for explosive devices and/or weapons. The invention may be useful for screening baggage at airports, but may be used for screening baggage at other locations.

Baggage screening systems are used to detect explosives and/or weapons in baggage checked with an airline, or the like. While carryon baggage has been screened for many years, there is a requirement that checked baggage be screened as well. While carryon bags are transported by the passenger through the screening process, there is no corresponding individual to process checked baggage through a screening system. As a result, attempts have been made at utilizing conveyor systems to transport baggage to one or more automated baggage screen devices and from the screen devices to the bag room.

While presently proposed systems facilitate the transport of baggage through the screening process, they are by no means operator-free. Baggage systems often handle bags in a random fashion, allowing the bags to become clustered and reoriented as the bags move through the system. The bags are then queued at an automatic baggage screening device which results in starting and stopping of the bags as they move up in the queue. The result is that opportunities are present for the bags to jam, especially during heavy traffic periods. Cameras are provided to monitor areas of frequent jamming in order to allow operators to detect and manually free up a jam. This results in a significant labor content in the baggage screening system which increases the cost of baggage screening. Moreover, jams increase the likelihood of damage to the bags and the contents thereof.

SUMMARY OF INVENTION

The present invention is directed to a baggage screening system and method that reduces the potential for bag jamming and thereby minimizes the number of operators to operate the system as well as minimizing damage to the bags and their contents.

A baggage screening system and method, according to an aspect of the invention, includes providing a plurality of screening subsystems, each including an automated baggage screen device and a feed conveyor for feeding bags to the screen device. A supply conveyor is provided for supplying bags to the screening subsystems. The supply conveyor supplies bags only to a screening subsystem that has no more than a particular number of unscreened bags that are at that screening subsystem. The number of unscreened bags may be one or fewer.

A method and apparatus for screening bags, according to another aspect of the invention, includes providing a plurality of automated baggage screen devices and a conveyor system. Bags are supplied individually to the screen devices with the conveyor system in a manner that bags travel substantially only at non-zero speeds to the screen devices.

A screening module for a baggage screening system having an automated baggage screen device and a supply conveyor for supplying bags to the screening module from a supply conveyor includes a feed conveyor for feeding bags to the screen device and a sortation conveyor downstream of the screen device. The feed conveyor includes a deceleration conveyor for decreasing speeds of individual bags being supplied to the baggage screen device. The sortation conveyor sorts bags as a function of the screening of the bags.

These and other objects, advantages and features of this invention will become apparent upon review of the following specification in conjunction with the drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now specifically to the drawings, and the illustrative embodiments depicted therein, a baggage screening system10includes at least one, and typically a plurality of, screen device(s)14and a conveyor system12. Conveyor system12supplies bags from an input end16, supplied from one or more check-in counters at which bags are supplied to the system, and an output portion18where bags are supplied to a bag room after having passed a screening procedure. Bags may be checked in at a ticket counter or loaded by an operator who manually places the bags on a conveyor. Alternatively, the bags may be handled by a conveyor which retrieves the bags from the passenger and supplies the bags to input portion16. Under either circumstance, bags can be expected to be supplied to input portion16in a singulated fashion without side-by-side bags and with the bags oriented in a particular fashion. Screen device14is commercially available from various suppliers, such as an EDS supplied by Invision Technologies. The particulars of the screen device are beyond the scope of the present invention. However, screen devices typically require that bags be passed through the device at a relatively slow speed, such as approximately 30 feet per minute or less. Such a speed is less than the speed of supply conveyor20and may be an order of magnitude less than that at which bags may be supplied at input portion16.

Conveyor system12includes a supply conveyor20and one or more screening modules, or subsystems,22. Supply conveyor20includes a recirculation conveyor24which recirculates bags from a downstream portion of supply conveyor20to an upstream portion thereof, as illustrated by the movement arrows inFIG. 1. Each screening module22includes a feed conveyor26for feeding bags from supply conveyor20to an associated screen device14and a sortation network28downstream of the screen device for sorting bags as a function of the outcome come of the screening of the bags. In particular, sortation network28sorts bags differently depending upon whether the bag passes or does not pass the initial screening. A diverter30is provided at an interface between supply conveyor20and a corresponding screening module22. When actuated, diverter30diverts a bag onto the corresponding feed conveyor26. When not actuated, the diverter allows the bag to pass to the next screening module and so on. In the illustrative embodiment, diverter30is of a type that controls orientation of a bag being diverted. In particular, diverter30is capable of aligning the bag with the general direction of movement of feed conveyor26. One such diverter is a powered-face diverter, such as the type disclosed in commonly assigned U.S. patent application Ser. Nos. 09/921,685, filed Aug. 3, 2001, by George W. Peppel for a HIGH SPEED BAGGAGE DIVERTER, and 60/456,777, filed Mar. 21, 2003, by Stephen C. Wolf for an ASYNCHRONOUS PADDLE DIVERTER, the disclosures of which are hereby incorporated herein by reference. However, other types of diverters may be utilized provided that the orientation of the bag is maintained. In the illustrative embodiment, the first diverter30encountered by a bag is illustrated in a non-actuated position, while the second diverter30is illustrated in an actuated position thereby diverting the bag to the middle-screening module22. The third actuator30in the direction of movement of the bags is also shown in an unactuated position.

Sortation conveyor network28includes a first leg34which receives bags cleared by screen device14and a second leg32which receives bags not cleared by screen device14. A diverter36is capable of diverting bags either to first leg32or second leg34. Diverter36may be of the same general configuration as diverter30or may be of a different configuration. Diverter36is expected to maintain orientation of the bag, but because the rate through each screen device14is lower than that on supply conveyor20, it may be of a lesser throughput alternative design.

A bag that passes the initial screening by the screen device14is diverted to first leg34and is collected at a cleared bag conveyor38and supplied to output portion18. Bags which do not pass the initial screening by screen device14are passed to second leg32for secondary screening. Second leg32includes a buffer conveyor40which allows the bag to be retained at second leg32. In the illustrative embodiment, secondary screening is conducted by an operator, who may be located remotely from baggage screening system10. The operator reviews an image captured by screen device14for that bag. The bag is retained at buffer40while the secondary image thereof is being reviewed. Based upon the review of the image of the bag performed at the secondary screening, the bag is either diverted to cleared bag conveyor38by a diverter42or is passed on to an uncleared conveyor line44. Conveyor line44passes the bag to a manual inspection station46. At manual inspection station46, the bags are subjected to further inspection, such as utilizing a trace detection system or other known manual inspection technique. Bags that pass the manual screening at46are joined with cleared bag conveyor38and passed to the bag room.

Feed conveyor26includes a deceleration conveyor portion48. In the illustrative embodiment, supply conveyor20is operated at a speed that is significantly greater than the speed of a transport conveyor50that transports the bags through the corresponding screen device14. By way of example, supply conveyor20may operate at a speed of 425 feet per minute while transport conveyor50may transport the bag through the corresponding screen device at a speed of 30 feet per minute. It should be understood that these are examples only and are not intended to be limiting. With such disparity in speeds, deceleration conveyor48decelerates the speed of a bag from the speed of supply line20to the speed of transport conveyor50. This may be accomplished by a sensor, such as a photo eye52which detects when a bag, which has been diverted by diverter30, is fully positioned on deceleration conveyor48such as by detecting the trailing edge of the bag. The deceleration conveyor is then decelerated from the speed of supply conveyor20to the speed of transport conveyor50. The bag is then discharged to transport conveyor50at the speed of conveyor50. Because the transition from supply conveyor20to deceleration conveyor48and from deceleration conveyor48to transport conveyor50occurs at a consistent speed across the transition, the orientation of the bag is maintained from diverter30to the screening device40. Deceleration conveyor48may be operated by a precision speed control, such as a variable frequency drive, servomotor drive, or the like.

Because diverter30controls the orientation of the bag which is initially oriented at input portion16, it can be seen that each bag is maintained in a controlled orientation from the check-in through the screen device. This significantly reduces the possibility of bag jamming and positions the bag for proper screening at the screen device. Advantageously, a limited number, such as only one bag, is present from diverter30to the output of transport conveyor50. In this manner, the bag is transported from the supply conveyor through the screen device at a non-zero speed without queuing of bags at an accumulation conveyor. This further avoids the opportunity for jamming and misorientation of the bags.

In operation, bags are supplied to input portion16from a bag check-in such as at a ticket counter at an airport, or the like. As the bag approaches the initial diverter30, a determination is made by a control computer (not shown) whether a bag is present at feed conveyor26and/or transport conveyor50. If not, diverter30is actuated and the bag is diverted to the associated screening module22. If there is a bag at either feed conveyor26or transport conveyor50, the diverter is not actuated and the bag is passed to the next screening module. Again, a determination is made whether a bag is present at the feed conveyor26or transport conveyor50of that screening module. If such a bag is not present, the diverter is actuated and the bag is diverted to that screening module for screening. This process continues until the bag is either diverted to a screening module or is recirculated by recirculation conveyor24back to an upstream portion, such as input portion16, of supply conveyor20. The baggage screening system1is a pull-system in which bags are diverted only when the screening module is ready to accept the bag and transport the bag through the screen device at a non-zero speed and without queuing of the bag. Bags are recirculated as needed until they arrive at an available screening module. The whole time bags are maintained in proper orientation and may be tracked by the central computer, such as by photo eyes, or the like. This also significantly reduces the necessity for frequent scanning of barcodes and or radio frequency tags on the bags.

Once a bag is inspected by screen device14, it is not returned to the supply conveyor20. Bags that are cleared either at the initial screening or by the secondary screening are immediately collected at a cleared bag conveyor and sent to the bag room. Bags that are not cleared by the initial or secondary screening are gathered by an uncleared conveyor and supplied to manual inspection. Such an arrangement reduces the possibility of an uncleared bag being passed to the bag room while promptly passing cleared bags to the bag room. It is also seen that the present invention provides a compact configuration that may be readily inserted into a baggage flow of an existing baggage handling system.

An example of a screening subsystem, or module,22is illustrated inFIG. 2. In the screening module illustrated therein, buffer conveyor40is illustrated as a series of short conveyors40a,40b. . .40n. When a bag is not cleared by screen device14, it is diverted by diverter36to buffer40. The bag is transported at a low speed, such as the inspection speed of transport conveyor50, as the bags are passed from conveyor40nthrough conveyor40a. If the bag is processed during secondary inspection, the bag continues to diverter42. The speeds of buffer conveyor sections40a-40nare set in order to allow sufficient time for secondary screening of the bags, such as by a manual inspection of the image produced by screening device14. If the bag is still not screened by the time it reaches the end of buffer conveyor section40a, the bag will be passed to conveyor44for subsequent manual screening. Although buffer conveyor40is illustrated inFIG. 2as a series of separately driven belt conveyors, it can also be a single belt conveyor that is driven at an appropriate speed in order to allow the bags to have their images manually reviewed. In the embodiment illustrated inFIG. 2, diverter conveyor42is a vertical diverter, such as the type disclosed in commonly assigned U.S. patent application Ser. No. 10/054,778, filed Jan. 23, 2002, by George W. Peppel, for a VERTICAL DIVERTER ASSEMBLY, the disclosure of which is hereby incorporated herein by reference. In the embodiment illustrated inFIG. 2, vertical diverter42diverts uncleared bags to uncleared conveyor44which is at a lower elevation than buffer conveyor40and diverts bags cleared by the secondary screening to cleared bag conveyor38which is at a similar elevation to buffer40.

Screen device14may be elevated at the level of an elevated platform52which is vertically raised above a floor54(FIG. 3). Platform52may be accessed by stairs56from floor54. Screen device14would be supported by supports (not shown) which extend to floor level54. In this configuration, screen device14may be replaced by removing a section of platform52and lowering the screen device to the level of floor54, such as utilizing a conventional lift mechanism. The screen device can then pass under platform52or a portion of sortation conveyor network28. This allows the screen device to be readily moved out of the baggage screening system10for maintenance and/or for upgrade to a new screening technology without the necessity of disassembling a portion of conveyor system12or utilizing overhead cranes which are expensive and require additional overhead clearance.

In an alternative embodiment, a screening module122, which is otherwise generally the same as screening module22, utilizes a diverter142to divert uncleared bags to uncleared conveyor44which is at the same elevation as cleared bag conveyor38. This is accomplished by a horizontal diverter142which laterally diverts bags not cleared by the secondary screening to uncleared conveyor44. The advantage of the screening module inFIG. 4is that the cost is less than that inFIGS. 2 and 3as a result of utilizing a horizontal, rather than a vertical, divert of bags exiting the secondary screening.

In an embodiment illustrated inFIG. 5, a pair of divert modules222are supplied in mirror image to each other in order to utilize a common uncleared baggage conveyor44(FIG. 5). Otherwise, screening modules222are the same as screening module122. Also, screening module22could be adapted to the configuration inFIG. 5.

Thus, it is seen that the present invention provides a baggage screening system that significantly reduces the opportunity for jamming of bags thereby minimizing human intervention and damage to bags and their contents. Because bags are processed through the screen device without stopping, there is minimal slippage and tumbling of bags which disrupt orientation. Indeed, speed and orientation of the bags are controlled from the check-in counter to the screen device. The “pull-system” utilized by the present invention avoids the use of queuing of bags at the screen device which ensures that bag orientation may be maintained.