# US 7,746,486 B2 · Pellet sorting by diameter measurement

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 7,746,486 B2
- Document ID: US7746486B2
- Status: Granted
- Kind: B2
- Application number: 12/083,901
- Filed: 2006-10-16
- Published: 2009-04-23
- Granted: 2010-06-29
- Earliest claimed: 2005-10-18
- Assignees: Areva Nc
- Inventors: Philippe Ferlet
- Web page: https://patentgrep.com/patent/US7746486B2

## CPC

- G01B 11/10: of objects while moving
- B07C 5/10: measured by light-responsive means {(sorting according to colour B07C5/342)}
- G21C 21/02: Manufacture of fuel elements or breeder elements contained in non-active casings
- Y02E 30/30: Nuclear fission reactors
- G01B: MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- B07C: POSTAL SORTING; SORTING INDIVIDUAL ARTICLES, OR BULK MATERIAL FIT TO BE SORTED PIECE-MEAL, e.g. BY PICKING (specially adapted for a specific purpose covered by another class, see the relevant place, e.g. A43D33/06, B23Q7/12)
- G21C: NUCLEAR REACTORS (fusion reactors, hybrid fission-fusion reactors G21B; nuclear explosives G21J)
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION

## Abstract

A system based on the continuous measurement (20) of the diameter of a cylindrical object (1) moving, laid down, on a belt conveyor (10) allows dimensional compliance of the latter object to be checked. The measurement system (20) may be coupled with a sorting system based on ejection out of the conveyor (10) by projecting a gas through a transverse nozzle (42). By means of the system according to the invention, it is possible to continuously determine whether a nuclear fuel pellet (1), in particular after rectification (2), has to be rejected or not.

## Claims

### Claim 1

A method for checking dimensional compliance of cylindrical objects comprising:
displacement at a predetermined velocity of the objects in a direction parallel to their axis (AA);
interaction of a beam with the object perpendicularly to its displacement direction;
determination of the diameter of a plurality of sections of the object by means of the representative signal of the interaction of said beam;
computation of a diameter representative of the object on the basis of the determined diameters (Dλ) of the sections;
computation of a characteristic k representative of the length L of the object on the basis of the number k of sections li for which the diameter Dλ was determined;
comparison of the computed diameter d and length L with thresholds dmin, dmax, kmin, kmax with which the compliance of the object may be checked.

### Claim 2 (depends on 1)

The method according to claim 1, next comprising a selection of objects depending on their compliance.

### Claim 3 (depends on 2)

The method according to claim 2, comprising the actuation of sorting means depending on the comparisons of the diameter and length (d, L) in order to provide selection.

### Claim 4 (depends on 3)

The method according to claim 3, wherein the actuation of the sorting means comprises the opening of a solenoid valve for a determined time Ti, and selection is provided by a blowing gas passing through the solenoid valve.

### Claim 5 (depends on 1)

The method according to claim 1 applied to nuclear fuel pellets.

### Claim 6

A device for determining compliance of pellets comprising:
linear conveying means;
a system for determination of a single dimension Dλ perpendicular to the conveying direction and during the conveying;
means for storing determined dimensions Dλ;
means for computing representative values of the length and diameter of the pellet by means of the plurality of the sole stored dimensions Dλ and for comparing the values with thresholds;
a sorting system downstream from the determination system associated with the conveying means;
means for actuating the sorting system via the results of the comparisons by the comparing means.

### Claim 7 (depends on 6)

The device according to claim 6, wherein the computing means comprise means for averaging a certain number of stored dimensions Dλ.

### Claim 8 (depends on 6)

The device according to claim 6, wherein the sorting system is a pressurized gas ejection nozzle perpendicular to the conveyor.

### Claim 9 (depends on 8)

The device according to claim 8, comprising a solenoid valve connected to the ejection nozzle and controlled by the means for actuating the sorting system.

### Claim 10 (depends on 8)

The device according to claim 8, wherein the conveying means comprise two parallel edges along the conveying direction, one of the edges being at least arranged at the ejection nozzle.

### Claim 11 (depends on 6)

The device according to claim 6, wherein the determination system comprises a laser micrometer.

### Claim 12 (depends on 6)

The device according to claim 6, associated with a glove box.