Method and apparatus for forming a cylindrical member

An apparatus for forming a cylindrical member comprising:

• a forming drum for forming a belt-shaped member cut to a predetermined length by winding the belt-shaped member therearound;
• an auxiliary bar having a shape of a substantially triangular prism and capable of being attached to or removed from said forming drum in parallel with an axis of said forming drum;
• transfer means for transferring said auxiliary bar to and away from a surface of said forming drum;
• belt-shaped member supplying means for supplying the belt-shaped member toward said forming drum with said auxiliary bar attached thereto to cause a leading end of the belt-shaped member to be attached to one of side surfaces of said auxiliary bar, and for further supplying the belt-shaped member onto said forming drum being rotated to cause the belt-shaped member to be wound around said forming drum and to cause a trailing end of the belt-shaped member to be attached to another side surface of said auxiliary bar;
• belt-shaped member gripping means for holding and releasing the leading end and the trailing end of the belt-shaped member attached to said auxiliary bar;
• and
• moving means for moving said belt-shaped member gripping means in such a manner as to move the leading end and the trailing end of the belt-shaped member away from said auxiliary bar and to cause the leading end and the trailing end to butt against each other after said auxiliary bar is removed from said forming drum.

An apparatus for forming a cylindrical member, comprising:

• a forming drum for forming a belt-shaped member cut to a predetermined length by winding the belt-shaped member therearound;
• an auxiliary bar having a shape of a substantially triangular prism and capable of being attached to or removed from said forming drum in parallel with an axis of said forming drum;
• transfer means for transferring said auxiliary bar to and away from a surface of said forming drum;
• belt-shaped member supplying means for supplying the belt-shaped member toward said forming drum with said auxiliary bar attached thereto to cause a leading end of the belt-shaped member to be attached to one of side surfaces of said auxiliary bar, and for further supplying the belt-shaped member onto said forming drum being rotated to cause the belt-shaped member to be wound around said forming drum and to cause a trailing end of the belt-shaped member to be attached to another side surface of said auxiliary bar;
• belt-shaped member gripping means including a plurality of leading-end gripping pawls and trailing-end gripping pawls for holding and releasing the leading end and the trailing end of the belt-shaped member attached to said auxiliary bar, said leading-end gripping pawls and trailing-end gripping pawls being arranged alternately along the axis of said forming drum, each of said leading-end gripping pawls and trailing-end gripping pawls including an upper pawl and a lower pawl which oppose each other, and an upper moving mechanism for gripping the end of the belt-shaped member between said upper pawl and said lower pawl by causing said upper pawl to approach said lower pawl, and grooves into which said lower pawls can be inserted being formed on the side surfaces of said auxiliary bar attached to said forming drum;
• and
• moving means for moving said belt-shaped member gripping means in such a manner as to move the leading end and the trailing end of the belt-shaped member away from said auxiliary bar and to cause the leading end and the trailing end to butt against each other after said auxiliary bar is removed from said forming drum.