To provide a releasing mechanism that can perform, even with relatively simple constitution, release operations with good response and low noise while improving the working environment.

When a release signal is sent to servomotors 410, 411 linking with the press working of a pressing part 300, the servomotors 410, 411 are turned and the output members 422, 423 of ball screw parts 420, 421 are moved in the releasing direction. In accordance with this movement, an upper work roll supporting member 430 which is connected to the output members 422, 423 through connecting parts 424, 425 is moved in the releasing direction and upper work rolls 242 which are supported with the upper work roll supporting member 430 are moved in the releasing direction. In this way, a workpiece 2 which is conveyed between the upper work rolls 242 and lower work rolls 244 is released.