FANUC Series 30i/300i/300is-MODEL A. Machining Center System. User's manual - page 34

PROGRAMMING

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9. SPINDLE SPEED FUNCTION

(S FUNCTION)

Limitation
- Constant surface speed control for threading

The constant surface speed control is also effective during threading.
Accordingly, it is recommended that the constant surface speed
control be invalidated with G97 command before starting the scroll
threading and taper threading, because the response problem in the
servo system may not be considered when the spindle speed changes.

- Constant surface speed control for rapid traverse (G00)

In a rapid traverse block specified by G00, the constant surface speed
control is not made by calculating the surface speed to a transient
change of the tool position, but is made by calculating the surface
speed based on the position at the end point of the rapid traverse block,
on the condition that cutting is not executed at rapid traverse.

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9.SPINDLE SPEED FUNCTION

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Example

300 400 500 600 700 800 900 1000 1100

1200

1300 14001500

1050

1475

200

375

500

300

400

700

N16

N15

N14

N11

100

675

600

Programmed path

Tool path after offset

Radius value

600

400

N8 G00 X1000.0Z1400.0 ;
N9 T33;
N11 X400.0Z1050.0;
N12 G50S3000 ; (Designation of max. spindle speed)
N13 G96S200 ; (Surface speed 200 m/min)
N14 G01 Z 700.0F1000 ;
N15 X600.0Z 400.0;
N16 Z_ ;
The CNC calculates the spindle speed which is proportional to the
specified surface speed at the position of the programmed coordinate
value on the X axis. This is not the value calculated according to the X
axis coordinate after offset when offset is valid. At the end point N15
in the example above, the speed at 600 dia. (Which is not the turret
center but the tool nose) is 200 m/min. If X axis coordinate value is
negative, the CNC uses the absolute value.

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9. SPINDLE SPEED FUNCTION

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9.4

SPINDLE POSITIONING FUNCTION

Overview

In turning, the spindle connected to the spindle motor is rotated at a
certain speed to rotate the workpiece mounted on the spindle.    This
spindle control status is referred to as spindle rotation mode.
The spindle positioning function turns the spindle connected to the
spindle motor by a certain angle to position the workpiece mounted on
the spindle at a certain angle.    This spindle control status is referred
to as spindle positioning mode.

The spindle positioning function involves the following three
operations:
1.  Canceling the spindle rotation mode and entering the spindle

positioning mode

Place the spindle in the spindle positioning mode and establish a
reference position by specifying a given M code (set with a
parameter). (Spindle orientation)

2. Positioning the spindle in the spindle positioning mode

The spindle is positioned in either of the two methods:
1) Positioning with an arbitrary angle by an axis address
2) Positioning with a semi-fixed angle by a given M code (set

with a parameter)

3. Canceling the spindle positioning mode, and entering the spindle

rotation mode

Place the spindle in the spindle rotation mode by specifying a
given M code (set with a parameter).

The least command increment, least input increment, and maximum
value for the spindle positioning axis are as follows:

•

Least command increment

•

Least input increment

0.001 deg (IS-B)

•

Maximum

value

999999.999 deg

360

4096

= 0.088 deg (when the gear ratio of the spindle to the position coder

•

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9.4.1

Spindle Orientation

When spindle positioning is first performed after the spindle motor is
used for normal spindle operation, or when spindle positioning is
interrupted, the spindle orientation is required.
Orientation permits the spindle to stop at a predetermined position.
Orientation is directed by the M code set in parameter No. 4960. The
direction of orientation can be set with a parameter.
For the serial spindle, it is set in bit 4 (RETSV) of parameter No. 4000.
With the grid shift function, the orientation position can be shifted in a
range of 0 to 360 deg with parameter No. 4073 for a serial spindle.

- Feedrate during spindle orientation

An orientation feedrate for a serial spindle is determined by a spindle
parameter setting.
In orientation, the serial spindle stops at the orientation position after
several rotations of the spindle motor.

- Omission of orientation

By using bit 2 (ISZ) of parameter No. 4950, orientation upon
switching to spindle positioning mode can be omitted if it is
unnecessary (for example, when no start position is specified and
incremental positioning from the current position is only required).
More specifically, when an M code for switching to spindle
positioning mode is specified, the spindle control mode is simply
switched to spindle positioning mode and then the processing is
completed without orientation.

- Program reference position

The position at which orientation is completed is assumed to be a
program reference position. However, the program reference
position can be changed through coordinate system setting (G92 or
G50) or automatic coordinate system setting (bit 0 (ZPR) of parameter
No. 1201).
When a setting is made to omit orientation, a program reference
position is not established, and operation by an absolute command is
unpredictable during spindle positioning with an axis address.

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9.4.2

Spindle Positioning

The spindle can be positioned with a semi-fixed angle or arbitrary
angle.

- Positioning with a semi-fixed angle

Use an M code to specify a positioning angle. The specifiable M
code value may be one of the six values from M

to M (

+5). Value

must be set in parameter No. 4962 beforehand. The positioning

angles corresponding to M

to M (

+5) are listed below. Value

must be set in parameter No. 4963 beforehand.

M-code

(Ex.)

+ 5

Positioning angle

(Ex.)

= 30

M (

+ 1)

M (

+ 2)

M (

+ 3)

120

M (

+ 4)

150

M (

+ 5)

180

When the number of M codes to be used, value

, is specified in

parameter No. 4964, a specifiable M code value may be in a range of
values from M

to M (

+ (

- 1)), up to 255 values from M

to M (

+ (255 - 1)).

M code

(Ex.)

= 11

Positioning angle

(Ex.)

= 30

M (

+ 1)

M (

+ 2)

M (

+ 3)

120

...

... ...

M (

+ 11 - 1)

330

The direction of rotation can be specified in IDM (bit 1 of parameter
4950).

- Positioning with an arbitrary angle

Specify the position with an arbitrary angle using the axis address
followed by a signed numeric value or numeric values. The axis
address must be specified in the G00 mode.
(The explanation below is given assuming that a C axis address is set.)
(Example) C-45000
C180.000
A numeric with the decimal point can be entered. The value must be
specified in degrees.
(Example) C36.0=C36

degrees

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- Absolute commands and incremental commands

Incremental commands are always used for positioning with a
semi-fixed angle (using M codes).
The direction of rotation can be specified with bit 1 (IDM) of
parameter No. 4950.
Absolute and incremental commands can be used for positioning with
an arbitrary angle.
With absolute commands for positioning with an arbitrary angle, when
the rotation axis rollover function is used (bit 0 (ROA) of parameter
No. 1008 is 1), shortcut control is also enabled (bit 1 (RAB) of
parameter No. 1008 is 0).

Program reference position

180°

G-code system A in

lathe system

G-code system B or C in

lathe system, and

machining center system

Command format

Address

used

Command

A-B in the

above

figure

Address

used and G

code

Command

A-B in the

above

figure

Absolute
command

Specify the end
point with a
distance from the
program reference
position.

C180.0 ;

G90, C

G90 C180 .;

Incremental
command

Specify a
distance from
the start point to
the end point.

H90.0 ;

G91, C

G91 C90 .;

- Feedrate during positioning

The feedrate during positioning equals the rapid traverse speed
specified in parameter No. 1420.
For the specified speed, an override of 100%, 50%, 25%, and F0
(parameter No. 1421) can be applied.

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9.4.3

Canceling Spindle Positioning

When modes are to be switched from spindle positioning to normal
spindle rotation, the M code set in parameter No. 4961 must be
specified.

Also, the spindle positioning mode is canceled and the spindle rotation
mode is set in the following cases:
<1> A reset operation (including an emergency stop) occurs when a

servo alarm is issued.

<2> A reset operation (including an emergency stop) occurs when a

spindle alarm is issued.

<3> An orientation operation in progress is stopped due to a reset or

alarm, or for some other reason.

<4> A reset operation (including an emergency stop) occurs when bit

(IOR) 0 of parameter No. 4950 is 1.

CAUTION

1 During execution of spindle positioning sequences

(canceling the spindle rotation mode and entering
the spindle positioning mode, positioning the spindle
in the spindle positioning mode, and canceling the
spindle positioning mode and entering the spindle
rotation mode), the automatic operation stop signal
*SP is invalid. This means that automatic operation
does not stop until all the sequences are completed,
even when the *SP signal becomes 0.

2 Dry run and machine lock cannot be performed

during spindle positioning.

3 Auxiliary function lock is disabled for M codes for the

spindle positioning function.

4 The serial spindle Cs-axis contour control function

and the spindle positioning function cannot be used
at a time. If both options are specified, the spindle
positioning function has priority.

5 The spindle positioning axis is handled as a

controlled axis. Therefore, controlled axis-related
signals (such as the overtravel signal) must be set.

6 When using the rigid tapping function and the

spindle positioning function concurrently, do not
specify rigid tapping in spindle positioning mode or
spindle positioning in rigid tapping mode.

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NOTE

1 M code commands for positioning of a spindle must

be specified in a single block. Other commands must
not be contained in the same block. (Also, M code
commands for positioning of another spindle must
not be contained in the same block.)

Even when the single-block, multiple-M code
command function is also used, related M codes
must be specified in a single block.

2 Even when the single-block, multiple-M code

command function is also used, related M codes
must be specified in a single block.

3 Axis address commands for positioning of a spindle

must be specified in a single block. Other commands
must not be contained in the same block. However,
the following commands can be contained in the
same block where axis address commands are
specified:

G00, G90, G91, G92 (G-code systems B and C in
the T series, M series)
G00, G50 (G-code system A in the T series)

4 M code commands for spindle positioning specify M

codes that are not buffered.

5 Spindle positioning cannot be performed by manual

operation (in jog feed, manual handle feed, manual
numeric command, or other mode).

6 Spindle positioning cannot be performed by PMC

axis control.

7 For spindle positioning, program restart and block

restart operations cannot be performed. Use the
MDI for these operations.

8 The stored stroke limit check is disabled for the

spindle positioning axis.

9 The axis removal function is disabled for the spindle

positioning axis.

10 The pitch error compensation function is disabled for

the spindle positioning axis.

11 When a setting is made to omit spindle orientation,

the reference position return completion signal does
not become 1.

12 In spindle orientation, all-axis interlock and

axis-specific interlock are checked only when a block
is started. A signal is ignored if input during the
execution of the block.

13 A difference between a specified travel distance and

an actual travel distance is maintained until spindle
positioning mode is canceled.

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