RFID conveyor system

• US 20060238351A1
• Filed: 03/23/2006
• Published: 10/26/2006
• Est. Priority Date: 03/29/2005
• Status: Active Grant

• Current Assignee: Datalogic Automation Incorporated (Datalogic S.p.A.)
• Original Assignee: Accu-Sort Systems Incorporated (Datalogic S.p.A.)
• Inventors: Hillegass, Raymond R.
• Granted Patent: US 7,538,675 B2
• Time in Patent Office: Days
• US Class Current: 340/572.700
• CPC Class Codes: B07C 5/3412 according to a code applied to the object which indicates a property of the object, e.g. quality class, contents or incorrect indication sorting according to size measured by light-responsive means B07C5/10; sorting according to optical properties B07C5/342; for packages B65D79/02; for information carriers G06K7/00
• CPC Class Codes: B65G 2203/042 Sensors
• CPC Class Codes: G06K 17/00 Methods or arrangements for effecting co-operative working between equipments covered by two or more of main groups G06K1/00 - G06K15/00, e.g. automatic card files incorporating conveying and reading operations
• CPC Class Codes: G06K 2207/1012 Special detection of object
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10079 the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G06K 7/10346 the antenna being of the far field type, e.g. HF types or dipoles
• CPC Class Codes: G06K 7/10356 using a plurality of antennas, e.g. configurations including means to resolve interference between the plurality of antennas
• CPC Class Codes: G06K 7/10435 the interrogation device being positioned close to a conveyor belt or the like on which moving record carriers are passing conveying in accordance with bodily destination marks, see B65G47/46, sorting of objects carrying identity markings, see B07C5/34
• CPC Class Codes: G06Q 10/08 Logistics, e.g. warehousing, loading or distribution; Inventory or stock management
• CPC Class Codes: H01Q 1/2208 associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems methods or arrangements for sensing record carriers, e.g. for reading patterns G06K7/00; record carrier for use with machines and with at least a part designed to carry digital markings G06K19/00
• CPC Class Codes: H01Q 1/2216 used in interrogator/reader equipment
• CPC Class Codes: H01Q 1/2241 used in or for vehicle tyres
• CPC Class Codes: H01Q 17/001 for modifying the directional characteristic of an aerial
• CPC Class Codes: H01Q 21/065 Patch antenna array
• CPC Class Codes: H01Q 21/08 the units being spaced along or adjacent to a rectilinear path waveguide fed H01Q21/0037
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40
• CPC Class Codes: H01Q 9/0428 : radiating a circular polarised wave

Abstract

A conveyor system for processing items on which radio frequency identification tags are disposed includes a frame and a conveyor that is disposed moveably on the frame and that conveys items through a path of travel, each item having at least one respective radio frequency identification tag disposed thereon. A first antenna is disposed proximate the path of travel so that the first antenna radiates radio frequency signals into a first area that is proximate the conveyor and through which the items pass and receives responses to the radio frequency signals from the respective radio frequency identification tags. A second antenna is proximate the first antenna and the path of travel so that the second antenna radiates radio frequency signals into the first area. At least one radio frequency receiver receives signals from the first antenna corresponding to the responses received by the antennas from the respective radio frequency identification tags and outputs first signals corresponding to the responses. A processor receives the first signals and is programmed to associate a first signal with a first item when the processor receives the first signal while at least a portion of the first item is within a predetermined second area that includes at least part of the first area. The second antenna radiates radio frequency signals that interfere with reception of and response to the radio frequency signals from the first antenna by a respective radio frequency identification tag in the presence of radio frequency signals from the first antenna and the second antenna. The second antenna is disposed with respect to the first antenna and the conveyor so that the second antenna radiates radio frequency signals into a third area that is proximate to but generally excludes the second area.

Claims

1. A conveyor system for processing items on which radio frequency identification tags are disposed, said system comprising:

a frame;

a conveyor that is disposed movably on the frame and that conveys items through a path of travel, each item having at least one respective radio frequency identification tag disposed thereon;

a first antenna disposed proximate the path of travel so that the first antenna

radiates radio frequency signals into a first area that is proximate the belt and through which the items pass and

receives responses to the radio frequency signals from the respective radio frequency identification tags on the items on the belt;

a second antenna proximate the first antenna and the path of travel so that the second antenna

radiates radio frequency signals into the first area;

at least one radio frequency receiver that receives signals from the first antenna corresponding to the responses received by the first antenna from the respective radio frequency identification tags and outputs first signals corresponding to the responses; and

a processor that receives the first signals from the at least one receiver and is programmed to associate said first signal with a first said item when the processor receives the first signal from the at least one receiver while at least a portion of the first item is within a predetermined second area that includes at least part of the first area,

wherein the second antenna radiates radio frequency signals that interfere with reception of and response to the radio frequency signals from the first antenna by a said respective radio frequency identification tag in the presence of radio frequency signals from the first antenna and the second antenna, and wherein the second antenna is disposed with respect to the first antenna and the belt so that the second antenna radiates radio frequency signals into a third area that is proximate to but generally excludes the second area.

2. The system as in claim 1, wherein the second antenna is disposed upstream from the first antenna with respect to the path of travel.

3. The system as in claim 1, wherein

the first antenna comprises a first substrate and a plurality of first patch elements disposed on the first substrate so that generally planar respective top surfaces of the first patch elements are generally coplanar in a first plane that intersects a plane including a centerline of the path of travel at a first acute angle, and

the second antenna comprises a second substrate and a plurality of second patch elements disposed on the second substrate so that generally planar respective top surfaces of the second patch elements are generally coplanar in a second plane that intersects the plane including the centerline of the path of travel at a second acute angle.

4. The system as in claim 3, wherein the first antenna faces downstream with respect to the path of travel and the first acute angle is approximately 45 degrees, and wherein the second antenna faces upstream with respect to the path of travel and the second acute angle is approximately 45 degrees.

5. The system as in claim 3, wherein the first antenna faces downstream with respect to the path of travel and the first acute angle is approximately 45 degrees, and wherein the second antenna faces upstream with respect to the path of travel and the second acute angle is approximately 60 degrees.

6. A conveyor system for processing items on which radio frequency identification tags are disposed, said system comprising:

a frame;

a generally planar belt that is disposed movably on the frame and that conveys items through a path of travel, each item having at least one respective radio frequency identification tag disposed thereon;

a first antenna disposed proximate the belt so that the first antenna

radiates radio frequency signals into a first area that is proximate the belt and through which the items pass and

receives responses to the radio frequency signals from the respective radio frequency identification tags on the items on the belt;

a second antenna proximate the first antenna and the belt so that the second antenna radiates radio frequency signals into the first area;

at least one radio frequency receiver that receives signals from the first antenna corresponding to the responses received by the first antenna from the respective radio frequency identification tags and outputs first signals corresponding to the responses; and

a processor that receives the first signals from the at least one receiver and is programmed to associate said first signal with a first said item when the processor receives the first signal from the at least one receiver while at least a portion of the first item is within a predetermined second area that includes at least part of the first area,

wherein the second antenna radiates radio frequency signals that interfere with reception of and response to the radio frequency signals from the first antenna by a said respective radio frequency identification tag in the presence of radio frequency signals from the first antenna and the second antenna, and wherein the second antenna is disposed with respect to the first antenna and the belt so that the second antenna radiates radio frequency signals into a third area that is proximate to but generally excludes the second area.

7. The system as in claim 6, wherein the second antenna is disposed upstream from the first antenna with respect to the path of travel.

8. The system as in claim 6, wherein

the first antenna is disposed with respect to the belt so that a center of a gain pattern from the first antenna is oriented at an approximately 45 degree angle with respect to a line parallel to a center line of the belt,

the second antenna is disposed with respect to the belt so that a center of a gain pattern from the second antenna is oriented at an approximately 45 degree angle with respect to a line parallel to a center line of the belt, and

the first antenna faces downstream with respect to the path of travel and the second antenna faces upstream with respect to the path of travel so that the center of the gain pattern from the first antenna is oriented at an approximately 90 degree angle with respect to the center of the gain pattern from the second antenna.

9. The system as in claim 6, wherein

the first antenna is disposed with respect to the belt so that a center of a gain pattern from the first antenna is oriented at an approximately 45 degree angle with respect to a line parallel to a center line of the belt,

the second antenna is disposed with respect to the belt so that a center of a gain pattern from the second antenna is oriented at an approximately 60 degree angle with respect to a line parallel to a center line of the belt, and

the first antenna faces downstream with respect to the path of travel and the second antenna faces upstream with respect to the path of travel so that the center of the gain pattern from the first antenna is oriented at an approximately 105 degree angle with respect to the center of the gain pattern from the second antenna.

10. The system as in claim 6, wherein

the first antenna comprises a first substrate and a plurality of first patch elements disposed on the first substrate so that generally planar respective top surfaces of the first patch elements are generally coplanar in a first plane that intersects a plane including a centerline of the belt at a first acute angle, and

the second antenna comprises a second substrate and a plurality of second patch elements disposed on the second substrate so that generally planar respective top surfaces of the second patch elements are generally coplanar in a second plane that intersects the plane including the centerline of the belt at a second acute angle.

11. The system as in claim 10, wherein the first antenna faces downstream with respect to the path of travel and the first acute angle is approximately 45 degrees, and wherein the second antenna faces upstream with respect to the path of travel and the second acute angle is approximately 45 degrees.

12. The system as in claim 10, wherein the first antenna faces downstream with respect to the path of travel and the first acute angle is approximately 45 degrees, and wherein the second antenna faces upstream with respect to the path of travel and the second acute angle is approximately 60 degrees.

13. The system as in claim 6, wherein a power level at which the second antenna is driven is less than a power level at which the first antenna is driven.

14. The system as in claim 6, including

two said first antennas respectively disposed on opposite sides of the belt laterally offset from the belt with respect to the path of travel and facing the belt, and

two said second antennas disposed proximate respective said first antennas and facing the belt.

15. The system as in claim 14, wherein the two first antennas radiate radio frequency signals into the first area in a predetermined sequence with respect to each other, and the two second antennas radiate radio frequency signals into the first area simultaneously with each other and with radiation of radio frequency signals into the first area by the two first antennas.

16. The system as in claim 14, including

a said first antenna facing the belt and disposed on a side of the belt on which items are conveyed and that is offset from the belt so that items pass through the path of travel between the belt and said first antenna, and

a said second antenna disposed proximate the first antenna disposed on the side of the belt on which items are conveyed and facing the belt.

17. A conveyor system for processing items on which radio frequency identification tags are disposed, said system comprising:

a frame;

a generally planar belt that is disposed movably on the frame and that conveys items, each item having at least one respective radio frequency identification tag disposed thereon;

a first antenna disposed proximate the belt so that the first antenna

radiates radio frequency signals into a first area that is proximate the belt and through which the items pass and

receives responses to the radio frequency signals from the respective radio frequency identification tags on the items on the belt;

a second antenna proximate the first antenna and the belt so that the second antenna

radiates radio frequency signals into the first area;

at least one radio frequency receiver that receives signals from the first antenna corresponding to the responses received by the first antenna from the respective radio frequency identification tags and outputs first signals corresponding to the responses;

a processor that receives the first signals from the at least one receiver and is programmed to associate a said first signal with a first said item if the processor receives the first signal from the at least one receiver while at least a portion of the first item is within a predetermined second area that includes at least part of the first area; and

a radio frequency transmitter that drives the second antenna to radiate radio frequency signals that interfere with reception of and response to the radio frequency signals from the first antenna by a said respective radio frequency identification tag in the presence of radio frequency signals from the first antenna and the second antenna,

wherein the second antenna is disposed with respect to the first antenna and the belt so that the second antenna radiates radio frequency signals into a third area that is proximate to but generally excludes the second area.

18. The system as in claim 17, wherein the second antenna is disposed upstream from the first antenna with respect to the path of travel.

19. The system as in claim 17, wherein

the first antenna is disposed with respect to the belt so that a center of a gain pattern from the first antenna is oriented at an approximately 45 degree angle with respect to a line parallel to a center line of the belt,

the second antenna is disposed with respect to the belt so that a center of a gain pattern from the second antenna is oriented at an approximately 45 degree angle with respect to a line parallel to a center line of the belt, and

the first antenna faces downstream with respect to the path of travel and the second antenna faces upstream with respect to the path of travel so that the center of the gain pattern from the first antenna is oriented at an approximately 90 degree angle with respect to the center of the gain pattern from the second antenna.

20. The system as in claim 17, wherein

the first antenna is disposed with respect to the belt so that a center of a gain pattern from the first antenna is oriented at an approximately 45 degree angle with respect to a line parallel to a center line of the belt,

the second antenna is disposed with respect to the belt so that a center of a gain pattern from the second antenna is oriented at an approximately 60 degree angle with respect to a line parallel to a center line of the belt, and

the first antenna faces downstream with respect to the path of travel and the second antenna faces upstream with respect to the path of travel so that the center of the gain pattern from the first antenna is oriented at an approximately 105 degree angle with respect to the center of the gain pattern from the second antenna.

21. The system as in claim 17, wherein

the first antenna comprises a first substrate and a plurality of first patch elements disposed on the first substrate so that generally planar respective top surfaces of the first patch elements are generally coplanar in a first plane that intersects a plane including a centerline of the belt at a first acute angle, and

the second antenna comprises a second substrate and a plurality of second patch elements disposed on the second substrate so that generally planar respective top surfaces of the second patch elements are generally coplanar in a second plane that intersects the plane including the centerline of the belt at a second acute angle.

22. The system as in claim 21, wherein the first antenna faces downstream with respect to the path of travel and the first acute angle is approximately 45 degrees, and wherein the second antenna faces upstream with respect to the path of travel and the second acute angle is approximately 45 degrees.

23. The system as in claim 21, wherein the first antenna faces downstream with respect to the path of travel and the first acute angle is approximately 45 degrees, and wherein the second antenna faces upstream with respect to the path of travel and the second acute angle is approximately 60 degrees.

24. The system as in claim 17, wherein a power level at which the second antenna is driven is less than a power level at which the first antenna is driven.

25. The system as in claim 17, including

two said first antennas respectively disposed on opposite sides of the belt laterally offset from the belt with respect to the path of travel and facing the belt, and

two said second antennas disposed proximate respective said first antennas and facing the belt.

26. The system as in claim 25, wherein the transmitter drives the two first antennas to radiate radio frequency signals into the first area in a predetermined sequence with respect to each other and drives the two second antennas to radiate radio frequency signals into the first area simultaneously with each other and with radiation of radio frequency signals into the first area by the two first antennas.

27. The system as in claim 26, including

a said first antenna facing the belt and disposed on a side of the belt on which items are conveyed and that is offset from the belt so that items pass through the path of travel between the belt and said first antenna, and

a said second antenna disposed proximate the first antenna disposed on the side of the belt on which items are conveyed and facing the belt.

28. A method of processing items on each of which at least one respective radio frequency identification tag is disposed, where the items are conveyed through a path of travel by a generally planar belt that is disposed movably on a frame, said method comprising the steps of:

radiating first radio frequency signals into a first area that is proximate the belt and through which the items pass;

receiving responses to the first radio frequency signals from the respective radio frequency identification tags on the items on the belt and outputting first output signals that correspond to the responses;

associating a said first output signal with a first said item if the response that corresponds to the first output signal is received while at least a portion of the first item is within a predetermined second area that includes at least part of the first area; and

radiating second radio frequency signals, wherein the second radio frequency signals interfere with reception of and response to the first radio frequency signals by a radio frequency identification tag in the presence of the first radio frequency signals and the second radio frequency signals, into a third area that includes at least part of the first area and is proximate to but generally excludes the second area.