Method and apparatus for measuring and diverting an object from a high-speed conveyor

• US 6,690,995 B2
• Filed: 08/22/2002
• Issued: 02/10/2004
• Est. Priority Date: 08/24/2001
• Status: Expired due to Term

• Current Assignee: United Parcel Service Of America Incorporated (United Parcel Service Incorporated)
• Original Assignee: United Parcel Service Of America Incorporated (United Parcel Service Incorporated)
• Inventors: Prutu, Victor Nicholas
• Primary Examiner(s): Tran, Khoi H.
• Application Number:
  US10/226,376
• Publication Number:
  US 20030075416A1
• Time in Patent Office: 537 Days
• Field of Search: 198/459.1, 198/460.1, 198/570, 198/571, 198/572, 198/597, 198/598, 700/228, 700/213, 700/230
• US Class Current: 700/228
• CPC Class Codes: B07C 1/10 Sorting according to size or flexibility
• CPC Class Codes: B07C 5/34 Sorting according to other particular properties material testing per se G01N; quality control G07C3/14
• CPC Class Codes: B65G 43/08 Control devices operated by article or material being fed, conveyed or discharged and controlling the discharging devices B65G47/42
• CPC Class Codes: G01G 11/00 Apparatus for weighing a continuous stream of material during flow; Conveyor belt weighers
• CPC Class Codes: G01G 19/005 with electric or electronic computing means
• CPC Class Codes: G01M 1/122 Determining position of centre of gravity

Abstract

A method and apparatus for measuring and sorting parcels, including the concept of determining at least one component of the gravity center of said parcels. Determination of the gravity center component includes the use of a tilting action in combination with the use of sensors to sense the movement of the parcels as they tilt. Another concept includes the use of sensors to determine whether a parcel is sufficiently rigid to provide a tilting action, or whether the parcel is flexible and thus does not provide a tilting action so much as it provides a flexing action over the pivot point.

Claims

1. A conveying apparatus for evaluating a plurality of parcels being conveyed thereon, said plurality of parcels having differing lengths, said plurality of parcels including a parcel, said apparatus comprising:

A) a first conveyor defining a first conveying surface and including an exit location;

said first conveyor having a first conveyor portion which includes a crest located adjacent the exit location;

B) a first sensor configured for sensing the presence of a first parcel portion of said parcel while said parcel is on said conveying surface, said first sensor configured to provide a first sensor signal when said first parcel portion moves out of the sensing range of said first sensor due either to tilting of said parcel over said crest, or alternatively due to movement of said parcel along said first conveyor portion without tilting, said first sensor being a first distance from said exit location;

C) a second sensor configured for sensing the presence of a second parcel portion of said parcel while said parcel is on said conveying surface, said second sensor configured to provide a second sensor signal when said second parcel portion moves out of the sensing range of said second sensor due to tilting of said parcel over said crest, or alternatively due either to movement of said parcel along said first conveyor portion without tilting, said second sensor being a second distance from said exit location, said second distance being less than said first distance; and

D) a signal processing device for receiving said first and second signals and for determining for each of said parcels if one of two conditions is met;

1) a first condition in which said first and second sensor signals are generated within a predetermined time;

2) a second condition in which said first and second sensor signals are not generated within said predetermined time, said signal processing device providing a different output regarding parcel length depending on whether said first or second condition is met;

whereby a tilting evaluation is also based upon the determination of said first or second condition.

2. The apparatus as claimed in claim 1, wherein parcel length is estimated to be longer than a predetermined length if a parcel satisfies said first condition and parcel length is estimated to be shorter than a predetermined length if a parcel satisfies said second condition.

3. A conveying method of evaluating a plurality of parcels having different physical lengths, said method comprising the steps of:

A) providing a conveyor having a conveying path which includes a crest portion over which said plurality of parcels may be individually tilted from a first, nontilted, position to a second, tilted, position while being conveyed along said path;

B) providing a first sensor proximate said conveying path and positioned a first distance relative to said crest;

C) providing a second sensor proximate said conveying path and positioned a second distance relative to said crest, said second distance being less than said first distance;

D) conveying said plurality of parcels along said conveying path such that each parcel tilts over said crest;

E) determining for each of the parcels if one of the following two conditions has been met;

1) a first condition in which parcel tilting begins while said parcel is still being sensed by both said first and second sensors;

or

2) a second condition in which parcel tilting is done after said parcel has passed out of the range of said first sensor but while still being sensed by said second sensor,

F) estimating parcel length for each of said parcels based on whether said parcel satisfies said first or said second condition.

4. The method as claimed in claim 3, wherein parcel length is estimated to be longer than a given predetermined length if a parcel satisfies said first condition and wherein parcel length is estimated to be shorter than a given predetermined length if a parcel satisfies said second condition.

5. A conveying apparatus for evaluating a plurality of parcels being conveyed along a conveying path, said plurality of parcels having differing lengths, but each including a first and a second parcel portion said conveying apparatus particularly configured to evaluate tilting characteristics of said parcels as they are conveyed along said conveying path, said conveying apparatus comprising:

A) a conveyor assembly itself including;

1) a first conveyor portion along said conveying path for conveying parcels thereon without tilting; and

2) a crest portion along said conveying path and positioned proximate the end of said first conveyor portion, said crest portion configured such that parcels passing over said crest portion tilt over said crest portion and away from said first conveyor portion;

B) a first sensor positioned a first distance from said crest and having a sensing range, said first sensor configured to provide a first sensor signal when a first parcel portion of a given parcel moves out of said sensing range of said first sensor due either to tilting of said parcel over said crest, or alternatively due to movement of said parcel along said first conveyor portion without tilting;

C) a second sensor positioned a second distance from said crest said second distance less than said first distance, said second sensor having a sensing range and configured to provide a second sensor signal when a second parcel portion of a given parcel moves out of said sensing range of said second sensor due either to tilting of said parcel over said crest, or alternately due to movement of said parcel along said first conveyor portion without tilting; and

D) a signal processing device for receiving said first and second sensor signals and for determining if one of the following two conditions is met for a given parcel;

1) a first condition in which said first and second sensor signals are generated within a predetermined time period, upon which said signal processing device assumes said parcel is tilting out of the range of both said first and second sensors at the same time;

or

2) a second condition in which said first and second signals are not generated within a predetermined time period, whereupon said signal processing device assumes said parcel has passed said first sensor and is only tilting out of the range of said second sensor,

said signal processing device further making a tilting evaluation based upon the determination of said first or second condition, said tilting evaluation for purposes of accuracy using said first sensor signal under said first condition, and said tilting evaluation using said second signal under said second condition.

6. The conveying apparatus as claimed in claim 5, further comprising means for providing a signal to said signal processing means corresponding to the distance said parcel has passed over said crest at the point said parcel begins tilting, for purposes of gravity center estimation.

7. The conveying apparatus as claimed in claim 6, wherein a curtain sensor is used to sense when said parcel has passed over said crest.

8. The conveying apparatus as claimed in claim 5, wherein said first conveyor portion is a belt conveyor, and wherein said crest portion is a tilting roller.

9. The conveying apparatus as claimed in claim 5, wherein said first conveyor portion is a belt conveyor, and wherein said crest portion is the downstream end of said belt conveyor.

10. A method for evaluating the tilting characteristics of parcels being conveyed along a conveying path, said parcels having different lengths, said method comprising the steps of:

A) providing a conveyor assembly itself comprising;

1) a first conveyor portion along said conveying path for conveying parcels thereon without tilting; and

2) a crest portion along said conveying path and positioned proximate the end of said first conveyor portion, said crest portion configured such that parcels passing over said crest portion tilt over said crest portion and away from said first conveyor portion;

B) placing a first sensor a first distance from said crest, said first sensor having a sensing range and configured to provide a first sensor signal when a first parcel portion of a given parcel moves out of the sensing range of said first sensor due either to tilting of said parcel over said crest, or alternately due to movement of said parcel along said first conveyor portion without tilting;

C) placing a second sensor a second distance from said crest, said second distance being less than said first distance, said second sensor having a sensing range and configured to provide a second sensor signal when a second parcel portion of a given parcel moves out of the sensing range of said second sensor due either to tilting of said parcel over said crest, or alternately due to movement of said parcel along said first conveyor portion without tilting;

D) determining if either of the following conditions are met for a given parcel;

1) a first condition in which parcel tilting begins while said parcel is still being sensed by both said first and second sensors;

or

2) a second condition in which parcel tilting begins after said parcel has passed said first sensor and is out of the range of said first sensor, but said parcel is still being sensed by said second sensor; and

E) performing a tilting evaluation based upon the determination of said first or second condition, said tilting evaluation for purposes of accuracy using said first sensor signal under said first condition, and said tilting evaluation using said second signal under said second condition.

11. A method of evaluating the physical characteristics of parcels being conveyed along a conveying path, said method comprising the steps of:

A) defining a flexibility standard distinguishing more flexible parcels from less flexible parcels;

B) positioning a plurality of sensors proximate a portion of said conveying path, said sensors positioned such that if they can all sense a portion of a given parcel at the same time said parcel passes along said conveying path portion, said parcel is considered more flexible under said flexibility standard, but if all said sensors cannot sense a portion of a given parcel at the same time said parcel passes along said conveying path portion, said parcel is considered less flexible under said flexibility standard;

C) conveying a parcel along said conveying path portion while sensing said parcel with said plurality of sensors; and

D) based upon the sensation of said parcel by said sensors in step “

C”

, making a determination of whether said parcel is more flexible or less flexible under said flexibility standard.

12. The method as claimed in claim 11, wherein in step “

B”

, a crest is included along said conveying path portion, said crest causing inflexible parcels to tilt, while flexible parcels flex over said crest and wherein at least one of said plurality of sensors is positioned on one side of said crest.

13. A method of evaluating the flexibility of each of a plurality of parcels being conveyed along a conveying path, said plurality of parcels including more flexible and less flexible parcels being correspondingly more and less flexible than a predetermined parcel flexibility, said method comprising the steps of:

A) providing a first conveyor assembly along said conveying path, said first conveyor assembly defining a first supporting surface plane and including a crest at its downstream end along said conveying path;

B) providing a second conveyor assembly along said conveying path and downstream of said first conveyor assembly to allow passage of parcels from said first to said second conveyor assembly, said second conveyor assembly defining a second supporting surface plane being at an angle relative to said first supporting surface plane such that less flexible parcels tend to tilt as a unit but not to deform when passed from said first conveyor assembly to said second conveyor assembly, but such that more flexible parcels tend not to tilt as a unit but to deform over said crest when passed from said first conveyor to said second conveyor;

C) positioning a first sensor proximate said first supporting surface plane and positioning a second sensor on the opposite side of said crest and proximate said second supporting surface plane, said sensors being positioned such that a more flexible parcel of sufficient length will flex while passing over said crest and trigger both sensors, whereas a less flexible parcel will trigger only one sensor at a time while passing along said conveying path; and

D) conveying parcels along said conveying path and making distinctions between more flexible and less flexible parcels based on the output of said first and second sensors.

14. The method of claim 13, wherein said distinction in Step D comprises assignment of a predetermined gravity center location if a more flexible parcel is recognized.

15. The method of claim 13, wherein Step A includes providing said first conveying assembly with a tilting roller to form said crest.

16. A conveying apparatus for evaluating the flexibility of each of a plurality of parcels being conveyed along a conveying path, said plurality of parcels including more flexible and less flexible parcels being correspondingly more and less flexible than a predetermined parcel flexibility, said apparatus comprising:

A) a first conveyor assembly along said conveying path, said first conveyor assembly defining a first supporting surface plane and including a crest at its downstream end along said conveying path;

B) a second conveyor assembly along said conveying path and downstream of said first conveyor assembly to allow passage of parcels from said first to said second conveyor assembly, said second conveyor assembly defining a second supporting surface plane being at an angle relative to said first supporting surface plane such that less flexible parcels tend to tilt as a unit but not to deform when passed from said first conveyor assembly to said second conveyor assembly, but such that more flexible parcels tend not to tilt as a unit but to deform over said crest when passed from said first conveyor to said second conveyor;

C) a pair of sensors, comprising a first sensor proximate said first supporting surface plane and a second sensor on the opposite side of said crest and proximate said second supporting surface plane, said sensors being positioned such that a more flexible parcel of sufficient length will flex while passing over said crest and trigger both sensors, whereas a less flexible parcel will trigger only one sensor at a time while passing along said conveying path; and

D) a processing device for making distinctions between more flexible and less flexible parcels based on the output of said first and second sensors while said parcels are being conveyed along said path.

17. A method of conveying and evaluating a plurality of parcels having different physical characteristics, said plurality of parcels including more and less flexible parcels being correspondingly more and less flexible than a predetermined parcel flexibility, said method comprising the steps of:

making a determination that each of said parcels is a more or a less flexible parcel;

assigning a gravity center characteristic to each of said parcels according to a first or a second criteria, depending on whether said parcel is observed to be more or less flexible, respectively, such that a more flexible parcel is assigned a gravity center characteristic according to a first criteria, and such that a less flexible parcel is assigned a gravity center characteristic according to a second criteria;

conveying said plurality of parcels along a conveying path; and

ejecting all of said parcels from said conveying path, with consideration given to the assigned gravity center characteristic when determining where to contact said parcels for ejection thereof.

18. The method as claimed in claim 17, wherein said first criteria assigned to said more flexible parcels relates to a predetermined, constant gravity center characteristic.

19. The method as claimed in claim 17, wherein said second criteria assigned to said more flexible parcels relates to the use of a measured gravity center characteristic.

20. The method as claimed in claim 17, wherein said first criteria assigned to said more flexible parcels relates to the use of a predetermined, constant gravity center characteristic in that the gravity center is assumed to be located at a distance from the leading edge of the parcel which is 40 percent of the total parcel length.

21. A method of conveying and evaluating a plurality of parcels having different physical characteristics, said plurality of parcels including shorter and longer parcels being correspondingly shorter and longer than a predetermined length, said method comprising the steps of:

making a determination that each of said parcels is a longer or a shorter parcel;

assigning a gravity center characteristic to each of said parcels according to a first or a second criteria, depending on whether said parcel is observed to be shorter or longer, respectively, such that a longer parcel is assigned a gravity center characteristic according to a first criteria, and such that a shorter parcel is assigned a gravity center characteristic according to a second criteria;

ejecting all of said parcels from said conveying path, with consideration given to the assigned gravity center when determining where to contact said parcels for ejection thereof.

22. A conveying apparatus for evaluating the tilting characteristics of a parcel as it is conveyed along a conveying path, said apparatus comprising:

a first conveyor including an exit end, said first conveyor configured to convey parcels off of said first conveyor at a location proximate said exit end;

a second conveyor including an inlet end, said second conveyor configured to accept parcels onto said second conveyor at a location proximate said inlet end, said inlet end of said second conveyor and said first conveyor defining a gap therebetween;

a tilt roller positioned within said gap, said tilting roller configured such that said parcel rolls over and tilts over said tilting roller as said parcel is conveyed from said first conveyor towards said second conveyor, with said parcel tilting from a position in contact with said first conveyor and said tilting roller to a position in contact with said second conveyor and said tilting roller; and

at least one sensor to sense the tilting of said parcel as said parcel tilts over said tilting roller.

23. The conveying apparatus as claimed in claim 22, wherein said tilting roller is an idler roller.