Device and method for producing roll-formed part

1 . A roll-formed part production device, comprising:

rolls including:

a transfer roll that contacts at least an outer periphery of a workpiece and transfers the workpiece in a longitudinal direction;

a support roll that is located downstream of the transfer roll on a bending path and that contacts at least an inner periphery of the workpiece and defines a support point at which the workpiece is bent, the support roll including an inner support roll and an outer support roll; and

a bending roll that is located downstream of the support roll on the bending path and that contacts at least the outer periphery of the workpiece and bends the workpiece;

a roll driver actuator that moves the transfer roll, the support roll, and the bending roll in a width direction of the workpiece; and

circuitry including a processor and memory, wherein

an amount of movement of each of the rolls in the width direction is set as an amount of contact movement of each of the rolls in accordance with a position of the workpiece in the longitudinal direction based on the width dimension of the workpiece,

an amount of movement of the workpiece in the width direction at a point where the workpiece contacts the support roll is set as an amount of origin shift in accordance with the position of the workpiece in the longitudinal direction based on the amount of contact movement of the support roll,

an amount by which each of the rolls moves in the width direction in accordance with the position of the workpiece in the longitudinal direction is set as a first amount of movement of each of the rolls by combining the amount of contact movement of each of the rolls and the amount of origin shift,

an amount by which the bending roll moves in the width direction in accordance with the position of the workpiece in the longitudinal direction to bend an outer contour of the workpiece to a predetermined curvature is set as a second amount of movement based on a shape of the workpiece at the point where the workpiece contacts the support roll, and

the circuitry is configured to:

obtain an amount of movement corresponding to a sum of the first and second amounts of movement of the bending roll as an amount of movement of the bending roll in the width direction; and

based on the obtained amount of movement of the bending roll in the width direction, operate the roll driver actuator that moves the bending roll.

2 . The roll-formed part production device according to claim 1 , wherein the circuitry is further configured to:

obtain the first amount of movement of the transfer roll as an amount of movement of the transfer roll in the width direction;

based on the obtained amount of movement of the transfer roll in the width direction, operate the roll driver actuator that moves the transfer roll;

obtain the first amount of movement of the support roll as an amount of movement of the support roll in the width direction; and

based on the obtained amount of movement of the support roll in the width direction, operate the roll driver actuator that moves the support roll.

3 . The roll-formed part production device according to claim 1 , wherein:

the second amount of movement is obtained based on an outer contour shape of the workpiece that has not yet been subjected to bending by the bending roll.

4 . The roll-formed part production device according to claim 1 , wherein:

the second amount of movement is obtained based on at least a moment of inertia of area, a web width, or a cross-sectional area of the workpiece at the point where the workpiece contacts the support roll.

5 . The roll-formed part production device according to claim 3 , wherein:

the second amount of movement is obtained based on an amount of spring back that occurs in the workpiece that has been bent.

6 . The roll-formed part production device according to claim 1 , wherein:

the workpiece is a single-sided varying-contour workpiece that, before bending by the bending roll, has the outer contour shaped as a straight line and an inner contour shaped as a varying contour,

the circuitry is configured to obtain an amount of movement as an amount by which the bending roll moves in the width direction during bending by the bending roll, and

the amount of movement obtained as the amount by which the bending roll moves in the width direction during bending by the bending roll corresponds to a sum of a constant value that is the first amount of movement of the bending roll and the second amount of movement.

7 . The roll-formed part production device according to claim 1 , wherein:

the workpiece is a double-sided varying-contour workpiece that, before bending by the bending roll, has the outer contour and an inner contour both of which are shaped as varying contours,

the support roll includes an inner support roll that contacts the inner periphery of the workpiece and an outer support roll that contacts the outer periphery of the workpiece,

the circuitry is further configured to:

control the roll driver actuator to move the transfer roll, the outer support roll, and the bending roll in the width direction in accordance with variation of the outer contour in the width direction at points where the workpiece contacts the transfer roll, the outer support roll, and the bending roll; and

obtain the amount of contact movement of the bending roll as the first amount of movement of the bending roll, and

the amount of contact movement of the bending roll is an amount of variation of the outer contour in the width direction at the point where the workpiece contacts the bending roll.

8 . The roll-formed part production device according to claim 1 , wherein:

the workpiece is a double-sided varying-contour workpiece that, before bending by the bending roll, has the outer contour and an inner contour both of which are shaped as varying contours,

the support roll includes an inner support roll that contacts the inner periphery of the workpiece and an outer support roll that contacts the outer periphery of the workpiece,

the circuitry is configured to:

control the roll driver actuator to control a position of the outer support roll in the width direction such that an amount of movement of the outer support roll in the width direction differs from an amount of variation of the outer contour in the width direction at a point where the workpiece contacts the outer support roll; and

obtain an amount of movement as the first amount of movement of the bending roll,

the amount of movement obtained as the first amount of movement of the bending roll results from combining the amount of origin shift and the amount of contact movement of the bending roll,

the amount of origin shift is a difference multiplied by minus 1, the difference being that between an amount by which, when the workpiece is transferred without being bent, the outer contour varies in the width direction at the point where the workpiece contacts the outer support roll and an amount by which the outer support roll moves in the width direction when the workpiece is transferred without being bent, and

the amount of contact movement of the bending roll is an amount of variation of the outer contour in the width direction at a point where the workpiece contacts the bending roll.

9 . The roll-formed part production device according to claim 1 , wherein the bending roll has a sliding movement and a pivotal movement to maintain contact with the outer periphery or the inner periphery of the workpiece.