| 摘要 |
PROBLEM TO BE SOLVED: To provide a roll rotation detection device capable of properly detecting a rotation state of an undriven roll undriven by a driving source.SOLUTION: A rotation state of a bolt 7 of a magnetic substance for rotating together with a roll 6, is detected by using a vortex flow sensor 11 for detecting rotation of the roll 6. A bottomed cylindrical body 18 of projecting a tip detection part 12 of the vortex flow sensor 11 from a bottom part 19, is inserted into an insertion hole 15 provided in a chock 8. A penetration air hole 16 is continuously formed in the insertion hole 15, and when inserting the tip detection part 12 of the vortex flow sensor 11 into the penetration air hole 16, a sensor peripheral air discharge port 22 is formed on the whole periphery of the outer periphery of the tip detection part 12. A through-hole 20 is formed in the bottom part of the bottomed cylindrical body 18, and pressurized air flowed to the penetration air hole 16 via the through-hole 20 from the inside of the bottomed cylindrical body 18, is discharged to the whole periphery of the outer periphery of the tip detection part 12 from the sensor peripheral air discharge port 22. |
