Homing sequence strategies

Strategies

The sequence of homing of a machine axis depends on diverse factors, for example:

• Is there a reference cam?
• Is a zero pulse signal triggered?
• Is the reference cam to be moved to with cam play?

The various homing sequence strategies are subdivided into the following processes and are then considered in greater detail:

• Standard homing
• Homing on the fly for spindles
• Special homing processes

Standard homing

For standard homing, it is presumed there is a reference point cam switch and the position counter can be latched by a cam or a zero pulse signal.

The timing of standard homing generally takes place in three phases:

• Phase 1: travel to the reference cam
• Phase 2: travel from the reference cam
• Phase 3: travel to the reference cam with referencing

Three-phase standard homing includes two direction changes and the travel motions' parameters can be defined with two different speeds.

In variants of this method of homing, individual phases can be skipped. Homing can be reduced to one phase. In this case, no direction change takes place.

Homing on the fly for spindle axes

Homing on the fly is available only for spindle axes. For orientation of a spindle axis, i.e. positioning with M19, the spindle axis must be referenced. The spindle axis automatically performs homing if it is not yet referenced or if the reference point has been lost. This homing on the fly takes place while the spindle axis is rotating and without standstill.

Special homing processes

In special cases, standard homing cannot be applied. The following special homing processes point out further possibility of referencing an axis after appropriate parameter definition.

• Homing during travel from the cam
• Homing without reversing
• Homing only with zero pulse, without reference cam
• Homing in the direction of the valid travel range by inverting the reference direction and the cam signal level