Method and apparatus for checking the height of a mail item on the fly for franking purposes

• US 7,752,009 B2
• Filed: 01/28/2005
• Issued: 07/06/2010
• Est. Priority Date: 01/30/2004
• Status: Active Grant

• Current Assignee: Neopost Technologies S.A. (Quadient SA)
• Original Assignee: Neopost Technologies S.A. (Quadient SA)
• Inventors: Painault, Didier, Nicolas, Christian
• Primary Examiner(s): Cosimano; Edward R
• Application Number:
  US11/045,917
• Publication Number:
  US 20050187887A1
• Time in Patent Office: 1,985 Days
• Field of Search: 33/1.R, 337/00, 337/01, 337/72, 337/73, 337/76, 734/321, 738/658, 198/502.1, 198/502.2, 198/617, 250/200, 250/358.1, 250/359.1, 250/360.1, 250/491.1, 250/559.01, 250/559.12, 250/559.19, 250/559.24, 250/559.26, 356/625, 356/635, 356/638, 382/100, 382/101, 702/1, 702/127, 702/155, 702/158, 702/159, 702/163, 702/166, 702/189, 705/400, 705/401, 705/402, 705/406, 705/410
• US Class Current: 702/158
• CPC Class Codes: G07B 17/00661 Sensing or measuring mailpieces weighing G01G19/00
• CPC Class Codes: G07B 2017/0037 Calculation of postage value
• CPC Class Codes: G07B 2017/00685 Measuring the dimensions of mailpieces

Abstract

A method of checking the height of a mail item relative to at least one dimensional threshold SH defining a change in postage. The mail items are advanced at a constant speed V along a reference surface. The presence of a mail item is detected relative to a given point of the reference surface. First and second times t₁, t₂ for which the same mail item is present at the first and second distances d₁, d₂ relative to the reference surface is detected. The ratio t₂/t₁ is compared with a value equal to (1−ε), where ε represents a correction coefficient of less than 1 that depends on the tolerances for detection of the presence of a mail item. The height of a mail item is considered greater than the dimensional threshold SH if, and only if, the relationship t₂/t₁>1−ε is true.

Claims

1. A method of checking the height Hi of a mail item on the fly relative to at least one dimensional threshold SH defining a change in postage, each mail item having longitudinal peripheral edges of length Di and transverse peripheral edges of height Hi;

said method comprising;

causing the mail items to advance at a constant speed V along a reference surface so that each mail item is in contact with said reference surface over at least a portion of one of its longitudinal edges;

detecting the presence of a mail item relative to a given point of the reference surface firstly at a first distance d1 close to the reference surface and measured perpendicularly thereto, and secondly at a second distance d2 further away from the reference surface, measured perpendicularly thereto, and corresponding to said dimensional threshold SH;

detecting first and second times of presence t1, t2 for which the same mail item is present at said first and second distances d1, d2 relative to the reference surface;

comparing the ratio t2/t1 between the second and first times of presence at the second distance d2 and at the first distance d1 with a value equal to (1ε

), where ε

represents a correction coefficient of less than 1 that depends on the tolerances for detection of the presence of a mail item; and

considering that the height H of a mail item is greater than the dimensional threshold SH if, and only if, the relationship t2/t1>

1−

ε

is true.

2. A method according to claim 1, wherein the coefficient ε

lies approximately in the range 0.005 to 0.05, and preferably in the vicinity of 0.01.

3. A method according to claim 1, further consisting in determining the length Di of a mail item on the basis of the time of presence t1 and of the speed of advance V of the mail items.

4. A device for checking the height Hi of a mail item relative to at least one dimensional threshold SH on the fly and for franking purposes, said at least one dimensional threshold defining a change in postage, each mail item having longitudinal peripheral edges of length Di and transverse peripheral edges of height Hi;

said apparatus comprising;

a conveyor for conveying mail items as laid flat at a constant speed V along a guide defining a reference surface parallel to the direction of advance of the mail items placed on the conveyor;

jogger means for placing each mail item in contact with said reference surface over at least a portion of one of its longitudinal edges;

a first detector device that is rendered active when the presence of a mail item is detected relative to a given point of the reference surface at a first distance d1 close to the reference surface and measured perpendicularly thereto;

at least one second detector device that is rendered active when the presence of a mail item is detected relative to a given point of the reference surface at a second distance d2 further away from the reference surface, measured perpendicularly thereto, and corresponding to said dimensional threshold SH;

a counter device for counting first and second times of presence t1, t2 for which the first and second devices are rendered active as a mail item is going past; and

a computer and comparator device for computing the ratio t2/t1 between said second and first times, for comparing said ratio t2/t1 with a threshold value equal to (1−

ε

), where ε

represents a correction coefficient of less than 1 that depends on the tolerances for detection of the presence of a mail item, and for delivering information indicating that the height Hi of a mail item is greater than the dimensional threshold SH if, and only if, the relationship t2/t1>

1−

ε

is true.

5. Apparatus according to claim 4, wherein the coefficient ε

lies approximately in the range 0.005 to 0.05, and preferably in the vicinity of 0.01.

6. Apparatus according to claim 4, wherein the first and second detector devices comprise optical sensors.

7. Apparatus according to claim 4, wherein the counter device comprises at least one optical encoder.

8. Apparatus according to claim 4, further comprising a device for computing the length Di of a mail item on the basis of the first time of presence ti and of the speed V of advance of the mail items.