A device for applying coiling-tension to a slit band sheet comprising:
- a first stretched portion having a first belt reversing portion, which has an arc-shaped outer peripheral surface formed on a side of the first stretched portion, and a second belt reversing portion, which has an arc-shaped outer peripheral surface formed on opposite side of the first stretched portion, and wherein there is a predetermined gap between the first belt reversing portion and the second belt reversing portion;
- one or more first belts, each of the one or more first belts being made of materials having different coefficients of friction, wherein the one or more first belts have a side having a smaller coefficient of friction than that of the opposite side thereof, and the side of the one or more first belts having the with the arc-shaped outer peripheral surfaces of the first belt reversing portion and the second belt reversing portion, and wherein the one or more first belts are stretched in a ring shape to be freely rotated around the first stretched portion;
- a first pressing portion being in distance with a predetermined gap from the first belt reversing portion and being in distance with a predetermined gap from the second belt reversing portion, and wherein the first pressing portion is in contact with the side of the one or more first belts having the smaller coefficient of friction in a predetermined length;
- a first tension adjusting portion constructed to adjust a distance and a size of the predetermined gap between the first belt reversing portion and the first pressing portion, and adjust a distance and a size of the predetermined gap between the second belt reversing portion and the first pressing portion;
- a second stretched portion having a third belt reversing portion positioned to face the first belt reversing portion-, which has an arc-shaped outer peripheral surface formed on a side of the second stretched portion, and a fourth belt reversing portion, which has an arc-shaped outer peripheral surface formed on opposite side of the second stretched portion, and wherein there is a predetermined gap between the third belt reversing portion and the fourth belt reversing portion, and wherein the fourth belt reversing portion is positioned to face the second belt reversing portion;
- one or more second belts, each of the one or more second belts being made of materials having different coefficients of friction, wherein the one or more second belts have a side having a smaller coefficient of friction than that of the opposite side thereof, and the side of the one or more second belts having the smaller coefficient of friction are in contact with the arc-shaped outer peripheral surfaces of the third belt reversing portion and the fourth belt reversing portion, and wherein the one or more second belts are stretched in a ring shape to be freely rotated around the second stretched portion;
- a second pressing portion being in distance with a predetermined gap from the third belt reversing portion and being in distance with a predetermined gap from the fourth belt reversing portion, and wherein the second pressing portion is in contact with the side of the one or more second belts having the smaller coefficient of friction in a predetermined length;
- and
- a second tension adjusting portion constructed to adjust a distance and a size of the predetermined gap between the third belt reversing portion and the second pressing portion, and adjust a distance and a size of the predetermine gap between the fourth belt reversing portion and the second pressing portion,
- wherein the first tension adjusting portion changes a degree of tension of the one or more first belts from adjustment of a distance and a size of the predetermined gap between the first belt reversing portion and the second belt reversing portion,
- wherein the second tension adjusting portion is configured to change a degree of tension of the one or more second belts from adjustment of a distance and a size of the predetermined gap between the third belt reversing portion and the fourth belt reversing portion,
- wherein surfaces of the first belt reversing portion and the second belt reversing portion that form the predetermined gaps in the first stretched portion, are substantially planar, and
- wherein surfaces of the third belt reversing portion and the fourth belt reversing portion that form the predetermined gaps in the second stretched portion, are substantially planar.