| 摘要 |
PURPOSE:To prevent the generation of a head-end mark by estimating the front tip position of a strip and the overlapping time of the strips in coiling, basing on the change of the quantity of light emitted from a light emitting element of mandrel and received by a light receiving element of strip guide. CONSTITUTION:A fine slitted groove 13 is formed in the peripheral surface of a cylindrical body 1 which constitutes a mandrel 1, and plural light emitting elements 15 are arranged on the bottom surface of groove 13; recesses 16 are provided to the positions opposite to the groove 13 of the curved surface of a slit guide 9, and light receiving elements 17 used for detecting the light emitted from the elements 15 are layed in the recesses 16. When the front tip 2' of a strip 2 enters a down coiler to change the receiving light quantity of elements 17, the tip 2 position of strip 2 and the overlapping time of them are estimated by calculations to control the retreating quantity of a piston 7 of pressing cylinder 8 just before the overlapping. In this way, an impact force generating at the time of the overlapping of strips 2 is reduced, and the generation of a head-end mark is prevented. |
