Process and device for determining the camber of a sheet
AssigneeTFK Company, Inc.
InventorMartine E. Desrousseaux
Life of this patent
Estimating the term…
Abstract
A device for determining the camber of a sheet includes sensors for taking a reading of the shape of the sheet as well as a system for determing the head, body and foot of the sheet. The device also includes an apparatus for determining a usable region in the body of the sheet. Further provided is a system for calculating, in the usable region, various values permitting the determination of various parameters characterizing the camber of the sheet.
Claims27
Process for determining the camber of a sheet comprising:
- taking a reading of the shape of the sheet,
- determining three portions of the sheet respectively corresponding to a head, a body and a foot of the sheet,
- causing the sheet to travel on conveyor means between a source of light which extends throughout the width of conveyor means and a means for detecting portions of the source of light hidden by the sheet as it travels by, one of said source of light and said means for detecting being disposed above and the other being disposed below the conveyor means,
- initiating the detecting means at a given frequency to obtain successive samplings of the sheet and reconstitute the shape of the sheet,
- determining a variation in portions of the source of light hidden by the sheet between two predetermined samplings and comparing said variation with a given threshold for delimiting the body from the head and the foot of the sheet,
- delimiting at each end of the body of the sheet a search region between a first point (A,B) corresponding to the end of the body (BT) of the sheet and a second point (A',B') located at a given distance (d) from the first point, and determining in said search region a pair of end points (D,F) of the usable region such that for any selected first point (M) located between the second point (A',B') and one end point (D,F) of the usable region of the sheet, a rise between a median fiber of the sheet and a chord drawn between the second point (A'B') and the selected first point (M) is less than a given threshold, and for any selected first point (M) located between the first point (A,B) and the respective end point (D,F) of the usable region of the sheet, a rise between the median fiber of the sheet and a chord drawn between the second point (A',B') and the selected second point (M) is larger than said given threshold, and,
- determining on the body of the sheet a usable region, and calculating in the usable region different values permitting a determination of different parameters characterizing the camber in order to arrive at a measurement of the camber of the sheet.
Device for carrying out a process for determining the camber of a sheet which includes determining a head, a body and a foot of the sheet, as well as a usable region on the body of the sheet, different values are then calculated to allow a determination of different parameters characterizing the camber in order to arrive at a measurement of camber, said device comprising:
- means for taking a reading of the shape of the sheet,
- means for determining on the sheet three portions respectively corresponding to the head, the body and the foot of the sheet,
- means for determining on the body of the sheet a usable region wherein the means for determining the usable region comprise:
- means for delimiting at each end of the body of the sheet a search region (A-A', B-B') between a first point (A,B) corresponding to a respective end of the body (BT) and a second point (A',B') located at a given distance (d) from the first point (A,B) and
- means for determining in said search region a pair of end points (D,F) of the usable region such that for any selected first point (M) located between the second point (A',B') and an end point (D,F) of the usable region of the sheet, a rise between a median fiber of the sheet and a chord drawn between the second point (A',B') and the selected first point (M) is less than a given threshold and for any selected second point (M) located between the first point (A,B) and the respective end point (D,F) of the usable region of the sheet, the rise between the median fiber of the sheets and a chord drawn between the second point (A',B') and the selected second point (M) is larger than said given threshold, and
- means for calculating in the usable region different values permitting the determination of different parameters characterizing the camber in order to arrive at a measurement of the camber.
Device for carrying out a process for determining the camber of a sheet which includes determining a head, a body and a foot of the sheet, as well as a usable region on the body of the sheet, different values are then calculated to allow a determination of different parameters characterizing the camber in order to arrive at a measurement of camber, said device comprising:
- means for taking a reading of the shape of the sheet,
- means for determining on the sheet three portions respectively corresponding to the head, the body and the foot of the sheet,
- means for determining on the body of the sheet a usable region,
- means for calculating in the usable region different values permitting the determination of different parameters characterizing the camber in order to arrive at a measurement of the camber, and
- means for calculating the length of a principal chord (L) between the two end points (D,F) of the usable region, the length of a maximum rise between said chord and a median fiber of the sheet (T), the length of a pair of secondary chords (L1,L2) between the ends (D,F) of the usable region and a point (C) of the median fiber of the sheet where a rise (h) is largest and the length of maximum rises (h1,h2) between the secondary chords (L1,L2) and the median fiber of the sheet.
Dependencies are inferred from the claim text.