Method for controlling an electric cylinder and a control system for the electric cylinder

A method for controlling an electric cylinder in a device, wherein

• the device comprises
• an electric cylinder that moves a rod,
• a load detector attached to the rod that detects the load for pressurizing applied to a material to be pressed,
• a servomotor that drives the electric cylinder, and
• a position detector attached to the servomotor that is electrically connected to a servo amplifier, wherein
• the servo amplifier is electrically connected to the servomotor and to a servo controller and controls the movement of the servomotor, and wherein
• the servo controller is electrically connected to the load detector and the servo amplifier and outputs a control command to the servo amplifier so as to control the servomotor, wherein
• the method comprises:
• a step for controlling the movement of the rod, wherein in the servo controller a speed of the rod, a load for detecting a bump between the rod and the material to be pressed, a flag for stopping determining whether the driving of the rod should be allowed if the bump between the rod and the material is detected, and an allowable speed to bump for determining whether the speed of the rod is the value at which the rod should be crash stopped, are set, and wherein
• the servo controller drives the rod based on the speed of driving that has been input into the controller, and causes the load detector to provide to the servo controller a signal for the load for pressurizing corresponding to the load for pressurizing detected by the load detector, and wherein the following steps take place:
• a step for detecting a bump, wherein the servo controller determines whether the load for pressurizing is larger than or equal to the load for detecting a bump between the rod and the material, based on the signal for the load for pressurizing,
• a step for detecting a flag for stopping when a bump occurs, wherein the servo controller determines whether the flag is ON,
• a step for detecting an allowable speed to bump, wherein if the flag is OFF at the step for detecting the flag the servo controller determines whether the speed of the rod is greater than or equal to an allowable speed to bump, and
• a step for crash stopping, wherein if it is determined that the load for pressurizing is larger than or equal to the load for detecting the bump at the step for detecting a bump and it is determined that the flag is ON at the step for detecting a flag for stopping, or if it is determined that the speed of the rod is greater than or equal to the allowable speed to bump at the step for detecting an allowable speed to bump, then the rod is crash stopped by braking the rod or driving the rod in the reverse direction.