Rotation control device of working machine

A rotation control device for a working machine, the device comprising:

• an electric motor for rotatably driving a rotating body;
• operation means for issuing a rotation command for rotation of the rotating body;
• control means for controlling said electric motor based on the rotation command issued from said operation means;
• and
• a rotating speed detecting means for detecting a rotating speed of the rotating body,
• said control means performing speed control according to an operation amount of said operation means and imposing a limitation on a maximum value of accelerating torque according to said operation amount, wherein, when said operation means is positioned within a preset neutral range, said control means is adapted to perform position holding control of said rotating body, to store torque generated in said electric motor by the position holding control as on-the-spot holding torque, and to set, in accelerating the rotation, the higher of said on-the-spot holding torque stored and said accelerating torque produced according to the operation amount of said operation means, as electric motor torque for acceleration.

A rotation control device for a working machine, the device comprising:

• an electric motor for rotatably driving a rotating body;
• operation means for issuing a rotation command for rotation of the rotating body;
• control means for controlling said electric motor based on the rotation command issued from said operation means;
• and
• rotating speed detecting means for detecting a rotating speed of the rotating body,
• said control means performing speed control to set a target value of the rotating speed of the rotating body according to an operation amount of said operation means when a pressing work is not being performed, wherein, when performing a pressing work including pressing a part of said rotating body against an object of work, said control means performs torque control with feedback control to provide a target value of the torque according to the operation amount of said operation means instead of said speed control.

A rotation control device for a working machine, the device comprising:

• an electric motor for rotatably driving a rotating body;
• operation means for issuing a rotation command for rotation of the rotating body;
• control means for controlling said electric motor based on the rotation command issued from said operation means;
• and
• a rotating speed detecting means for detecting a rotating speed of the rotating body,
• said control means performing speed control according to an operation amount of said operation means to set a target value of the rotating speed of the rotating body when a pressing work is not being performed, wherein, when performing a pressing work including pressing a part of said rotating body against an object of work, said control means performs speed control with control to impose a torque limitation according to the operation amount of the operation means on said speed control.

A rotation control device of a working machine, the device comprising:

• an electric motor for rotatably driving a rotating body;
• operation means for issuing a rotation command for rotation of the rotating body;
• control means for controlling said electric motor based on the rotation command issued from said operation means;
• and
• a rotating speed detecting means for detecting a rotating speed of the rotating body,
• said control means performing speed control according to an operation amount of said operation means to set a target value of the rotating speed of the rotating body when a pressing work is not being performed, wherein, when an actually measured value of the rotating speed is smaller than a target value corresponding to the operation amount of said operation means, said control means performs speed control with control to impose a torque limitation on said speed control.