Fundamentals
Application
In conjunction with the control's tool measurement cycles, the tool touch probe enables you to measure tools automatically: the compensation values for tool length and radius are stored in the tool table and are accounted for at the end of the touch probe cycle. The following types of tool measurement are provided:
- Measurement of a stationary tool
- Measurement of a rotating tool
- Measurement of individual teeth
Related topics
- Calibrate the tool touch probe
Measuring a tool of length 0
Refer to your machine manual!
The optional machine parameter maxToolLengthTT (no. 122607) enables the machine manufacturer to define a maximum tool length for the tool measurement cycles.
HEIDENHAIN recommends that you always define tools with their actual tool length if possible.
The tool measuring cycles measure tools automatically. You can also measure tools defined with a length L of 0 in the tool table. To do this, the machine manufacturer must define a maximum tool length value in the optional machine parameter maxToolLengthTT (no. 122607). The control starts a search in which the actual tool length is roughly determined in the first step. This is followed by a fine measurement.
Cycle run
- The tool travels to a clearance height centered above the touch probe.
The clearance height equals the value of the optional machine parameter maxToolLengthTT (no. 122607).
- The control performs a rough measurement with the spindle standing still.
When measuring a stationary tool, the control will use the feed rate for probing defined in the machine parameter probingFeed (no. 122709).
- The control saves the roughly measured length.
- The control performs a fine measurement with the values from the tool measuring cycle.
Notes
- Observe the machine parameter value in the machine manual.
- Define tools with the actual tool length L
- Observe the machine parameter value in the machine manual
Setting machine parameters
- The touch probe cycles 480, 481, 482, 483, 484 can be hidden with the optional machine parameter hideMeasureTT (no. 128901).
Programming and operating notes:
- Before you start working with the touch probe cycles, check all machine parameters defined in ProbeSettings > CfgTT (no. 122700) and CfgTTRoundStylus (no. 114200) or CfgTTRectStylus (no. 114300).
- When measuring a stationary tool, the control will use the feed rate for probing defined in the probingFeed machine parameter (no. 122709).
Spindle speed setting
When measuring a rotating tool, the control automatically calculates the spindle speed and feed rate for probing.
The spindle speed is calculated as follows:
n = maxPeriphSpeedMeas / (r • 0.0063) where
Abbreviation | Definition |
---|---|
n | Rotational speed [rpm] |
maxPeriphSpeedMeas | Maximum permissible cutting speed in m/min |
r | Active tool radius [mm] |
Setting of the feed rate
The probing feed rate is calculated as follows:
v = measuring tolerance • n
Abbreviation | Definition |
---|---|
v | Probing feed rate [mm/min] |
Measuring tolerance | Measuring tolerance [mm], depending on maxPeriphSpeedMeas |
n | Shaft speed [rpm] |
probingFeedCalc (no. 122710) determines the calculation of the probing feed rate. The control provides the following options:
- ConstantTolerance
- VariableTolerance
- ConstantFeed
ConstantTolerance:
The measuring tolerance remains constant—regardless of the tool radius. With very large tools, however, the feed rate for probing is reduced to zero. The lower you set the maximum permissible rotational speed (maxPeriphSpeedMeas (no. 122712)) and the permissible tolerance (measureTolerance1 (no. 122715)), the sooner you will encounter this effect.
- VariableTolerance:
VariableTolerance:
The measuring tolerance is adjusted relative to the size of the tool radius. This ensures a sufficient feed rate for probing even with large tool radii. The control adjusts the measuring tolerance according to the following table:
Tool radius | Measuring tolerance |
---|---|
Up to 30 mm | measureTolerance1 |
30 to 60 mm | 2 • measureTolerance1 |
60 to 90 mm | 3 • measureTolerance1 |
90 to 120 mm | 4 • measureTolerance1 |
ConstantFeed:
The measuring feed rate remains constant; the measuring error, however, rises linearly with the increase in tool radius:
Measuring tolerance = (r • measureTolerance1)/ 5 mm) where
Abbreviation | Definition |
---|---|
r | Active tool radius [mm] |
measureTolerance1 | Maximum permissible error of measurement |
Setting for consideration of parallel axes and changes in the kinematics
Refer to your machine manual.
Using the optional machine parameter calPosType (no. 122606), the machine manufacturer defines whether the position of parallel axes and changes in the kinematics should be considered for calibration and measuring. A change in kinematics might for example be a head change.
Auxiliary or parallel axes cannot be probed, regardless of the setting of the optional machine parameter calPosType (no. 122606).
If the machine manufacturer changes the setting of the optional machine parameter, you need to recalibrate the tool touch probe.
Entries in the tool table for milling tools
Abbr. | Inputs | Dialog |
---|---|---|
CUT | The number of teeth of the tool for automatic tool measurement or cutting data calculation (maximum of 20 teeth) | Number of teeth? |
LTOL | Permitted tool length deviation in wear detection for automatic tool measurement. If the entered value is exceeded, the control locks the tool in the column TL (status L). Input: 0.0000...5.0000 | Wear tolerance: length? |
RTOL | Permitted tool radius deviation in wear detection for automatic tool measurement. If the entered value is exceeded, the control locks the tool in the column TL (status L). Input: 0.0000...5.0000 | Wear tolerance: radius? |
DIRECT. | Cutting direction of the tool for automatic tool measurement with a rotating tool. Input: –, + | Cutting direction (M3 = –)? |
R-OFFS | Position of tool upon length measurement, offset between the probe contact center and the tool center for automatic tool measurement. Default setting: No value entered (offset = tool radius) Input: –99999.9999...+99999.9999 | Tool offset: radius? |
L-OFFS | Position of tool upon radius measurement, distance between the probe contact top edge and the tool tip for automatic tool measurement. Is added to the offsetToolAxis machine parameter (no. 122707). Input: –99999.9999...+99999.9999 | Tool offset: length? |
LBREAK | Permitted tool length deviation in breakage detection for automatic tool measurement. If the entered value is exceeded, the control locks the tool in the column TL (status L). Input: 0.0000...9.0000 | Breakage tolerance: length? |
RBREAK | Permitted tool radius deviation in breakage detection for automatic tool measurement. If the entered value is exceeded, the control locks the tool in the column TL (status L). Input: 0.0000...9.0000 | Breakage tolerance: radius? |
Input examples for common tool types
Tool type | CUT | R-OFFS | L-OFFS |
---|---|---|---|
Drill | No function | 0: No offset required because tool tip is to be measured | |
End mill | 4: four cutting edges | R: Offset required because the tool diameter is greater than the contact plate diameter of the TT | 0: No additional offset required during radius measurement. Offset from offsetToolAxis (no. 122707) used. |
Spherical cutter with a diameter of 10 mm | 4: four cutting edges | 0: No offset required because the south pole of the ball is to be measured. | 5: At a diameter of 10 mm, the tool radius will be defined as offset. If this is not the case, the diameter of the spherical cutter will be measured too far down. So the tool diameter will not be correct. |