3 digitizing an arc tangent at end points – Rockwell Automation 8520 9/Series CNC Lathe User Manual

Page 140

Editing Programs On Line

Chapter 5

5-34

After the second point on the arc has been stored reposition the axes

at the end point of the arc. Store this block as a circular block by

pressing either the

{STORE END PT}

or the

{EDIT & STORE}

softkeys.

This records the current tool location as the final position for this

digitize operation.

If you press:

It:

{STORE
END PT}

does not return the control to the program display screen. Pressing

this softkey inserts the generated block at whatever location the cursor

was last at and allows the operator to immediately begin entering the

next block using this same digitize feature.

{EDIT &

STORE}

returns the control to the program display screen. The program block

just generated is displayed on the input line of the CRT and may be

edited as discussed in section 2.10. This block is then inserted at the

location of the block cursor when you press the [TRANSMIT] key.

Important: To abort the circular digitize operation, press the exit {

}

softkey at any time before you press the

{STORE END PT}

{EDIT & STORE}

softkeys. The control returns to softkey level 4. Then

select either another digitize feature (by pressing one of the softkeys) or

the control can be returned to the regular edit session by pressing the exit
{

} softkey [as described on page 5-4].

The following subsection assumes that steps 1-5 on page 5-28 have been
completed to initiate a digitizing operation.

To digitize an arc tangent at end points:

Press the

{CIRCLE TANGNT}

softkeys if the circle is tangent at the

endpoint of the previous cutting path.

When you press the

{CIRCLE TANGNT}

softkey, the control sets the

current tool position as the start point of a circular move. The screen

displays the current tool location in large display characters.

If the previous block was circular, use a tangent to the end point of

the arc as the tangent point to the following block.

Important: You cannot select the

{CIRCLE TANGNT}

feature as the first

motion block in a part program. There is no path for the start of the arc to

be tangent to.

5.4.3

Digitizing An Arc Tangent at

End Points