Security scanner with bin return device

1. A security screening system for scanning items, the system comprising:

a scanner, configured to produce x-ray projection data as an object is passed through the scanner, at least a portion of the scanner being received within a structure, the structure having an input opening and an outlet opening, the input opening being configured to receive objects to be scanned and the outlet opening being configured to receive objects scanned by the scanner;

an input conveyor for passing a plurality of bins through the input opening to the outlet opening, the input conveyor having an input end for receiving the plurality of bins to pass the plurality of bins into the input opening and an output end for delivering the plurality of bins from the outlet opening;

a return conveyor positioned to return the plurality of bins to an area proximate to the input end of the input conveyor, the return conveyor being positioned below the input conveyor, wherein the return conveyor does not pass through the scanner; and

a sensor positioned with respect to the return conveyor, the sensor configured to sense a bin on the return conveyor.

2. The security screening system as in claim 1 , wherein the return conveyor extends past the input end and the output end of the input conveyor.

3. The security screening system as in claim 1 , wherein the return conveyor is driven by a motor and the return conveyor has an input end proximate to the output end of the input conveyor and an output end proximate to the input end of the input conveyor, wherein the sensor is positioned to detect the presence of one of the plurality of bins at the output end of the return conveyor, wherein the sensor provides a stop signal to the motor when the presence of one of the plurality of bins is detected at the output end of the return conveyor and the sensor provides a start signal to the motor when the presence of one of the plurality of bins is not detected at the output end.

4. The security screening system as in claim 3 , wherein the return conveyor extends past the input end and the output end of the input conveyor.

5. The security screening system as in claim 3 , wherein the input end of the return conveyor is below the input conveyor and the input end of the return conveyor is fed by a plurality of rollers arranged to define a downwardly inclined path from the output end of the input conveyor to the input end of the return conveyor.

6. The security screening system as in claim 5 , wherein the return conveyor comprises an upwardly inclined portion ending at the output end of the return conveyor.

7. The security screening system as in claim 1 , further comprising a platform positioned to receive at least one of the plurality of bins from an output end of the return conveyor, wherein the return conveyor is driven by a motor and the sensor is positioned to detect the presence of one of the plurality of bins on the platform, wherein the sensor provides a stop signal to the motor when the presence of one of the plurality of bins is detected on the platform and the sensor provides a start signal to the motor when the presence of one of the plurality of bins is not detected on the platform.

8. The security screening system as in claim 7 , wherein the platform extends past the input end of the input conveyor.

9. The security screening system as in claim 1 , wherein each of the plurality of bins comprises a peripheral wall and a bottom, wherein the peripheral wall and the bottom define a receiving area, and a forward portion and a rearward portion of the peripheral wall comprise an x-ray inhibiting material, wherein the forward portion and the rearward portion are each configured to substantially occupy the input opening or the outlet opening of the structure when either the forward portion or the rearward portion pass through the input opening and the outlet opening of the structure, wherein the forward portion and rearward portion prevent x-rays from exiting the structure through either the input opening or the outlet opening of the structure.

10. The security screening system as in claim 9 , wherein the peripheral wall further comprises a pair of side walls each extending between the forward portion and the rearward portion, the pair of side walls each having an exterior surface and an interior surface;

an indicator disposed on the exterior surface of one of the pair of side walls and the x-ray inhibiting material is lead integrally molded into the forward portion and the rearward portion; and

the security screening system further comprises a scanner configured to detect the presence of the indicator of one of the plurality of bins, wherein the indicator and the scanner are located to provide a signal when one of the plurality of bins is located proximate to either the input opening or the outlet opening of the structure and the x-ray inhibiting material of the bin is disposed within either the input opening or the outlet opening of the structure and the scanner is prevented from producing the x-ray projection data unless the signal is generated.

11. The security screening system as in claim 9 , wherein the forward portion and the rearward portion of the peripheral wall are each configured to provide a predetermined distance between an object disposed in the receiving area and the x-ray inhibiting material of either the forward portion and the rearward portion of the peripheral wall.

12. The system as in claim 9 , wherein each of the plurality of bins are substantially uniform in size and configuration and the scanner is a spiral computed tomography scanner having an x-ray source and a detector array rotatably mounted to a gantry of the spiral computed tomography scanner and the system further comprises a plurality of rollers positioned at the input end and the output end of the input conveyor.

13. The system as in claim 1 , wherein the return conveyor is positioned directly below the input conveyor and wherein the return conveyor does not increase an overall dimension of the system.

14. A security screening system for scanning items, the system comprising:

a scanner, configured to produce x-ray projection data as an object is passed through the scanner, at least a portion of the scanner being received within a structure, the structure having an input opening and an outlet opening, the input opening being configured to receive objects to be scanned and the outlet opening being configured to receive objects scanned by the scanner;

an input conveyor for passing a plurality of bins through the input opening to the outlet opening, the input conveyor having an input end for receiving the plurality of bins to pass the plurality of bins into the input opening and an output end for delivering the plurality of bins from the outlet opening;

a return pathway positioned to return the plurality of bins to an area proximate to the input end of the input conveyor, the return pathway being positioned below the input conveyor, wherein the return pathway does not pass through the scanner; and

a sensor positioned with respect to the return conveyor, the sensor configured to sense a bin on the return conveyor.

15. The security screening system as in claim 14 , wherein the return pathway extends past the input end and the output end of the input conveyor and the security screening system is part of an airport security check point.

16. The security screening system as in claim 15 , wherein the return pathway is comprises a plurality of rollers and a portion of the return pathway is inclined downwardly away from the output end of the input conveyor, wherein the return conveyor further comprises a bumper positioned proximate to the input end of the input conveyor, wherein the bumper prevents the plurality of bins from rolling off an end of the return pathway.

17. The security screening system as in claim 14 , wherein the return pathway is positioned directly below the input conveyor and wherein the return pathway does not increase an overall dimension of the system.

18. The security screening system as in claim 14 , wherein each of the plurality of bins comprises a peripheral wall and a bottom, wherein the peripheral wall and the bottom define a receiving area, and a forward portion and a rearward portion of the peripheral wall comprise an x-ray inhibiting material, wherein the forward portion and the rearward portion are each configured to substantially occupy the input opening or the outlet opening of the structure when either the forward portion or the rearward portion pass through the input opening and the outlet opening of the structure, wherein the forward portion and rearward portion prevent x-rays from exiting the structure through either the input opening or the outlet opening of the structure.

19. The security screening system as in claim 18 , wherein the peripheral wall further comprises a pair of side walls each extending between the forward portion and the rearward portion, the pair of side walls each having an exterior surface and an interior surface;

an indicator disposed on the exterior surface of one of the pair of side walls and the x-ray inhibiting material is lead integrally molded into the forward portion and the rearward portion; and

the security screening system further comprises a scanner configured to detect the presence of the indicator of one of the plurality of bins, wherein the indicator and the scanner are located to provide a signal when one of the plurality of bins is located proximate to either the input opening or the outlet opening of the structure and the x-ray inhibiting material of the bin is disposed within either the input opening or the outlet opening of the structure and the scanner is prevented from producing the x-ray projection data unless the signal is generated.

20. The security screening system as in claim 18 , wherein the forward portion and the rearward portion of the peripheral wall are each configured to provide a predetermined distance between an object disposed in the receiving area and the x-ray inhibiting material of either the forward portion and the rearward portion of the peripheral wall.

21. A method for returning a plurality of empty bins used in a security screening process, the method comprising:

advancing a plurality of bins through a scanner using an input conveyor, the input conveyor having an input end for receiving the plurality of bins and an output end for delivering the plurality of bins, the scanner being configured to produce x-ray projection data as an object is passed through the scanner, at least a portion of the scanner being received within a structure, the structure having an input opening and an outlet opening, the input opening being configured to receive objects to be scanned and the outlet opening being configured to receive objects scanned by the scanner; and

returning the plurality of bins to the input end after they have passed through the scanner with a return conveyor, the return conveyor being configured to return the plurality of bins to an area proximate to the input end of the input conveyor, the return conveyor being positioned below the input conveyor without passing through the scanner, and the return conveyor including a sensor positioned with respect to the return conveyor, the sensor configured to sense a bin on the return conveyor.

22. The method as in claim 21 , wherein the return conveyor is driven by a motor and the return conveyor has an input end proximate to the output end of the input conveyor and an output end proximate to the input end of the input conveyor, wherein the sensor is positioned to detect the presence of one of the plurality of bins at the output end of the return conveyor, wherein the sensor provides a stop signal to the motor when the presence of one of the plurality of bins is detected at the output end of the return conveyor and the sensor provides a start signal to the motor when the presence of one of the plurality of bins is not detected at the output end.