Oscillating axes

	The availability of this function depends on the configuration and the concrete scope of version.

For specific machining technologies such as grinding, an oscillating axis movement is necessary which is executed largely independently of a contouring motion.

This motion referred to below as an "oscillating motion" is executed by the tool periodically reversing over the workpiece.

An oscillating axis during grinding is presented below as an example. The workpiece is machined by superposition of the oscillating X motion with positioning motions in the Y and Z axes.

Oscillating axes 2: — Fig. 19.2: Grinding with an oscillating axis

The essential characteristics of the oscillating motion result from the oscillating motion between two absolute positions and the feed rate

The oscillating motion is started and stopped, and its parameters defined, via the NC program

Any definition of the oscillating axis within the scope of the configured axes is allowed. The oscillating motion is asynchronous to the contouring motion.

Deactivation of the oscillating motion is done:

directly by an NC command
or implicitly at the transition of the programmed oscillating axis to the contouring motion
or implicitly when axes positions for the synchronization of decoding and interpolation are requested
or implicitly at the end of the NC program

By setting the slope type in the channel parameter [1]-26 (linear/non-linear slope) for the oscillating motion the nature of the speed profile in the dynamic phase can be defined.

The programming syntax is based on the axis-specific programming of independent axes. After the axis identifier, the parameters of the oscillating motion are defined via key words and, if applicable, an associated value:

<axis_name> [ OSC ON | OFFFEED<expr> | FREQ<expr> | TIME<expr>
[1ST_POS<expr>2ND_POS<expr>] | [ ZERO_POS<expr>EXCUR<expr>]
[1ST_DELT<expr>2ND_DELT<expr>] [NBR_OSC<expr>] ]

<axis_name> Name of the oscillating axis

OSC Identification for "Oscillating". must always be the first programmed keyword.

ON Oscillation on. Before the oscillating motion is started, first an active contouring motion is stopped at block end.

OFF Oscillation off. After that, the oscillating axis can be moved in normal contouring motion. Implicit deactivation of the oscillating motion when a new command is executed without previous cancellation.

FEED<expr> Feed rate of oscillating motion in path units/min

FREQ<expr> Frequency of oscillating motion in Hz

TIME<expr> Period of oscillating motion in s

1ST_POS<expr> First reversal position in mm

2ND_POS<expr> Second reversal position in mm

ZERO_POS<expr> Zero point of oscillating motion in mm

EXCUR<expr> Excursion in mm

1ST_DELT<expr> Waiting time at first reversal position in s

2ND_DELT<expr> Waiting time at second reversal position in s

NBR_OSC<expr> Number of oscillations

The characteristic of the oscillating motion is determined by the locations of the reversing positions and the axis feed rate. The reversing positions can either be specified directly or, as an alternative, are determined automatically via the zero position and the excursion.

The oscillating positions are always absolut positions.
After deactivation of the oscillating motion, stopping always takes place at oscillating position 2!

As an alternative, the oscillating speed can be determined via the feed rate, the frequency or the period.

If no restriction occurs due to the dynamic characteristic axis quantities, the frequency and the period are kept to exactly when using the linear slope, and approximately when using the non-linear slope.

Oscillating axes 3: — Fig. 19.3: Positioning during the oscillating motion

Programming examples

Specifying the oscillation travel distance via reversal positions

N10 X[OSC ON 1ST_POS=-100 2ND_POS=100 FEED=1000]

Specifying the oscillation travel distance via the zero position and the excursion, 10 oscillations

N20 X[OSC ON ZERO_POS=0 EXCUR=100 FEED=1000 NBR_OSC=10]

Specifying 1 Hertz oscillation frequency

N30 X[OSC ON ZERO_POS=0 EXCUR=100 FREQ=1]

Specifying a 4s period

N40 X[OSC ON ZERO_POS=0 EXCUR=100 TIME=4]

Oscillating motion with feed motion of a contouring axis

N50 X[OSC ON 1ST_POS=111 2ND_POS=222 FREQ=1] 
N60 G01 G90 Y500 F200

Oscillating with waiting times of 0.5 s each at the reversal positions

N70 X[OSC ON 1ST_POS-100 1ST_DELT0.5 2ND_POS200 2ND_DELT0.5 FEED1000]

Cancelling oscillation. Oscillation is stoped with reaching of reversal position 2:

N80 X[OSC OFF]

Fast stop of oscillation If an OFF is programmed in combination with FEED, the oscillation motion is stopped at once (feedhold for oscillation axis) and the reversal position 2 is directly moved with the new feed.

N90 X[OSC OFF FEED=5000]

	Specifying the equal sign between the key word and the value is optional.