Siemens sinumerik 840D sl Function Manual page 523

Detailed description
2.3 Technological features of clearance control
The meaning of the individual positions of the machining head is as follows:
1. Programmed position of the machining head
2. Actual position of the machining head with clearance control active before the orientation
3. Actual programmed position of the machining head after the change in orientation
4. Position of the machining head with clearance control active after the orientation change
The machining head movement visible on the machine when the change in orientation takes
place is direct from position 2 to position 4.
2.3 Technological features of clearance control
Clearance control is characterized by the following technological features:
• Dynamic Response
• Sensor characteristic
• Sensors
• Closed-loop control gain of clearance control
• Motion limitation
• Response on deactivation
• Programmable clearance setpoint
18
change
The overlaid sensor motion uses the current residual dynamic response that is still in
reserve after the programmed axis motion (velocity and acceleration). The proportion of
residual acceleration that must be used can be set as a percentage in a machine data.
The gain characteristic of a sensor can be defined with up to 10 interpolation points.
Two sensors with different gain characteristics (e.g. a mechanical and a capacitive
sensor) can be used simultaneously. The active sensor characteristic can be switched
over block-synchronously by means of a language command in the part program.
The closed-loop control gain configured in the NC machine data for clearance control can
be changed block-synchronously by means of a language command in the part program.
The lower and upper limits configured in the NC machine data for the axis movements
induced by clearance control can be changed block-synchronously by means of a
language command in the part program.
An alarm appears when a limit is reached. The alarm response (stop all traversing
movements or display only) can be configured. The current position offset can be frozen
by means of a PLC signal.
The deactivation response of the clearance control function can be programmed either for
synchronization with the current axis positions (no compensating movement) or for
compensating axis movements to the last programmed axis positions (axis positions
without clearance control).
An additional voltage value can be programmed in order to alter the setpoint distance set
in the sensor electronics on a block-related basis.
Special functions: Clearance Control (TE1)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0