- CNC machined parts in defense industry
- Aerospace CNC Machining
- CNC Parts in Rail Traffic industry
- CNC machining parts in communication industry
The classification of the nc machine tools ( 2)
article we introduce the classification of nc machine tool according to the movement way, in addition, we usually will be classified by way of servo system control, then we will see what according to this way of classification can be divided into:
1, the open loop controlled machine tool
that means open loop controlled machine tool without feedback control system, the system did not set position feedback element, usually adopt stepper motor as the actuator. Input data after the operation of numerical control system, issue instructions pulse, through the annular distributor and drive circuit, make the stepping motor turned a step away from the Angle of, again through the drive mechanism drives the workbench mobile a pulse equivalent distance. Moving parts of the movement speed and displacement is determined by the input pulse frequency and pulse number.
2 and a half closed loop nc machine tool
in the drive motor end or at the end of transmission screw to install the angular displacement detection device, by detecting the motor or screw Angle indirectly measured the actual location of the executive part or displacement, then feedback to the CNC system. To obtain higher accuracy than the open loop system, but its displacement accuracy is lower than that in the closed-loop system, compared with the closed loop system, the stability is easy to implement. Now most of the nc machine tools are widely used in the half closed loop feed servo system, large inertia of moving parts is not included in the machine tool detection range.
3, closed-loop control of CNC machine tools.
closed loop control of CNC machine tools, its controlling actuator motor can be used two dc or ac servo motor, and needs to have the position feedback and speed feedback, at any time in the processing to detect the actual displacement of moving parts, and timely feedback to the CNC system. It with the command signal obtained by interpolation arithmetic are compared, their difference and as the control signal of the servo controlling dynamic, leading to the displacement components to eliminate displacement error.