| 摘要 |
A device (10) for measuring the speed of oblong products (15) in movement along a determinate direction of feed (F) and emitting radiations, in particular rolled metal products (15) in a rolling line, comprises two sensors (12, 14) for radiations, disposed reciprocally at a close distance each to define a respective optical observation window (17, 19), disposed at a known and pre-arranged distance from each other. Each window (17, 19) is configured so as to always cover the image of a determinate portion (15a, 15b) of advancing product (15) equal to the width of the relative window (17, 19), irrespective of the movements made by said portion (15a, 15b) transversely to the direction of feed (F). The sensors (12, 14) are able to observe said portion (15a, 15b) of product (15) which is presented, on each occasion, in correspondence with the associated windows (17, 19) consecutively along the direction of feed (F), and are also able to measure continuously the intensity of the radiation emitted by the portion (15a, 15b) of product (15) in correspondence with the windows (17, 19). The device (10) also comprises an electronic processing unit (11) to determine, by processing electric signals associated with the intensity of radiation detected and arriving from the two sensors (12, 14), using mathematical algorithms based on the correlation principle, the time taken by the portion (15a, 15b) of product (15) to transit from a first window (17) to a second, successive window (19), and then, on the basis of the distance between said two windows (17, 19), to calculate the speed of the product (15). |
