Centroid DP-4 User manual

DP-4 Touch Probe
Operator's Manual
U.S Patent #6553682
Rev 2019-05-28
Cop right © 2003-2020 Centroid Corporation
Howard, PA 16841

DP-4 Quick Start Guide
1. Install Probe cable assembly #11085 i necessary. Re er to Common Cables picture on page 11,
connection diagram on page 12 and appropriate appendix data.
2. Connect coil cord to DP-4 and to bulkhead connector on probe cable assembly #11085. See
probe eatures and general description page 1. LED indicating light should be green when
connection is made then turn red when stylus mount boss is touched.
3. Set system control parameters. See appropriate Appendix or parameter settings. See “Output
Switch Logic Selection” page 5 i application requires a normally closed probe output
connection.
4. Con irm machine is responding to DP-4 input by running an automatic cycle without the probe
in the spindle and manually touching the DP-4 stylus mount boss. Re er to control operator's
manual on how to run automatic probing cycles.
5. Install a tool holder in the spindle then install the DP-4 and then the stylus. See Stylus
installation procedures on page 3 and per orm run-out adjustment as shown on page 3 and 4.
6. Review stylus travel limits on page 2 and ollow the detailed initial setup on page 6 to per orm
an automatic probing cycle at reduced speed.
7. Calibrate stylus tip size. See procedures on page 6.
8. Review “Per ormance Characteristics” page 8 to ensure good results.
9. Review Adjustments page 3,4,5 and Maintenance and Care page 9 to keep DP-4 in good
operational condition.
10. Probe is now ready to use.

TABLE OF CONTENTS
General Description Page 1
Speci ications Page 2
Stylus Installation and Alignment Procedures Page 3
Run-out Adjustment “Dialing-in”
When to check run-out and dial-in
Angular Alignment Adjustment
Output Switch Logic Selection Page 5
Initial Control/Probe Setup Procedure Page 6
Stylus Tip Diameter Calibration Page 6
Per ormance Characteristics Page 8
Maintenance and Care Page 9
Shipping Instructions Page 9
Kit Contents Page 10
Common Cables Page 11
Connection Diagram (universal) Page 12
Grid Digitizing Tips Page 13
Cutting a Copy o Digitized Part, Tips Page 14
Appendix A – Centroid Control System CNC12 application data
Appendix B – Centroid Control System CNC11 application data
Appendix C – Centroid Control System CNC10 application data
Appendix D – Non-Centroid Control System application data

DP-4 PROBE GENERAL DESCRIPTION AND SPECIFICATIONS
GENERAL DESCRIPTION:
The DP-4 is a “touch probe” intended for probing to find part zero’s, reference positions, locate bores,
bases, corners etc., and digitizing which allows for the copying of surfaces and shaped ob ects. The
user should first become familiar with the various parts and features of the probe as shown above to
facilitate assembly, installation and calibration. Read the stylus installation and alignment procedures
section before attempting assembly. Review the over-travel limits shown in the specifications.
Exceeding the limits will damage the probe and stylus.
MOUNTING FEATURES:
The mounting shank design allows installation in the spindle of most machines. Other mounting
options are easily installed by loosening the run-out ad ustment screws and removing the shank from
the body. These options include smaller diameter shank or magnet or custom made forms.
OUTPUT FEATURES:
The output signal is a sink type compatible with most control inputs that can be configured for
normally open or closed logic. See CONNECTION DIAGRAM UNIVERSAL section. This choice
can be specified when ordering or can be changed by the user via an internal umper block. The state
of the switch changes when the stylus physically touches a surface. The DP-4 can be easily interfaced
to any CNC control which accepts this common type of input signal. A high quality 5 pin connector
through the probe body provides a convenient disconnect point for the stock 6 foot retractile cord. A
positive lock/unlock sliding sleeve on the cord connector facilitate fast reliable set-up and removal.
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Mounting shank
Run-out ad ustment screws
Use 3/32” hex wrench
LED indicator light
Green = ready
Red = tripped
Angular alignment screws
Set at factory
Rubber seal
Stylus mount boss
Use 3/16” wrench on flats
Stylus tightening hole
DP-4 REAR VIEW
Electrical
connector
Core index screw
Flush with body
Body
End cap
Stylus stem
Stylus tip
DP-4 front and rear v ews shown w th opt onal stylus attached.
DP-4 FRONT VIEW

DP-4 SPECIFICATIONS:
Probing directions X+/-, Y+/-, Z-
Unidirectional repeatability (2 sigma) 0.00004” (1 micron)
Probe deflection force (X,Y) 3 ounce minimum with 40mm stylus
Pre-travel variation X-Y plane 0.001” with 40 mm stylus
Probe deflection force (Z) 9 ounce minimum
Probe body diameter and length D= 1.25” (31.8mm) L= 2.2” (56.4mm)
Mounting shank diameter and length D= 0.5” (12.7mm) L= 1.47” (37.2mm)
Stylus mount thread M3
Output signal Switch (FET open drain) 30V 50mA
Output logic Selectable normally open or closed
Power supply required 10 – 30 VDC 50mA
LED status indicator green = ready, red = tripped
Weight of probe and ½”shank 0.45 lb
Over travel limit angle (X,Y) +/- 10 degrees from vertical
Over travel limit (Z-) 0.15” (3.8mm)
Environmental IP54, Dust Proof
Note: To calculate actual X or Y over travel distance multiply stylus length by 0.173
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STYLUS INSTALLATION AND ALIGNMENT PROCEEDURES
Important: Read the complete alignment procedure before starting.
The run-out ad ustment procedure, also called “Dialing-in” is necessary to ensure that the center of the
probe tip is aligned with the center of the spindle rotation axis. This eliminates any undesired off-sets
between the probe and the cutting tool centers when digitizing or doing automated part set-up.
Requ red Tools:
3/16” open end wrench
3/32” hex wrench
0.001" or better Dial Indicator with Magnetic Base
0.500" Dedicated Tool Holder
STEP 1: Install the DP-4 Probe into the dedicated 0.500" tool holder.
STEP 2: Install the complete assembly into the milling machine spindle without the retractile cord.
STEP 3: Install the 2.5 or 5mm stylus in your DP-4 probe. Thread the stylus into the probe stylus
mount boss until finger tight. Insert the stylus tightening pin, from your tool kit, into the hole located at
the base of the stylus stem and place the 3/16" wrench, from your tool kit, on the flats of the stylus
mount boss. Refer to the picture below. Do not apply any twisting force with the 3/16" wrench; use the
wrench to counter the twisting force being applied to the stylus by the tightening pin. Excessive
twisting force applied to the probe could damage the sensor assembly!
Tightening stylus with wrench and pin
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RUN-OUT ADJUSTMENT:
STEP 4: Position the dial indicator, as shown in the photo below, with the finger of the dial indicator
on the front and center of the stylus ball. Insert the 3/32” hex wrench in the run-out ad ustment set
screw directly above the finger of the dial indicator. Loosen the set screw by turning the hex wrench
counter clockwise while watching the dial indicator reading decrease. Turn the hex wrench clockwise
and watch the dial indicator reading increase.
Run-out Adjustment set-up and effect of Set Screw Movement
STEP 5: Rotate the spindle by hand (without touching the probe) so that the probe spins through a
full 360 degrees and watch the dial indicator to locate the high and low run-out rotation positions of the
stylus. Ad ust the dial indicator so that the entire run-out of the tip can be seen on the dial. If the run-
out exceeds the range of the dial then begin at the highest point of the run-out and set the dial indicator
so it is at the limit of its range at this point.
STEP 6: Rotate the probe so that the nearest run-out ad ustment set screw is above the finger tip
of the indicator. Using the 3/32" hex wrench slowly turn the setscrew directly above the indicator
finger, in the counter clock-wise direction, the dial indicator will show the reduction in the run-out.
Stop loosening this set screw and tighten the set screw that was nearest the low run-out position. Do not
allow the probe to become loose on the mounting shank.
STEP 7: Repeat steps 5 and 6 until no run-out of the tip is visible on the dial indicator needle. If
the screws become too tight before you have finished the ad ustment, do not force them, instead
loosen the setscrew that corresponds with the highest reading on the dial indicator, (refer to figure 3.2)
and tighten the set screw at the lowest reading. Only ad ust a set screw when it is directly above the
indicator finger. This way you can see the full effect of the ad ustment you are making.
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WHEN TO CHECK RUN-OUT:
Any time the probe is removed from its holder, the stylus is changed or the probe is used in a different
machine, the alignment procedure should be repeated to ensure accuracy. The user should also repeat
the alignment procedure if the unit is dropped or receives any sudden external shock. It is good practice
to periodically check alignment for quality control and to establish a base line maintenance schedule.
ANGULAR ALIGNMENT:
Angular alignment is the relation of the spindle center line to the stylus stem center line. This
ad ustment provides for equal clearance all around the stylus stem. This ad ustment is rarely needed
except when extremely small or long stylus is used. When the stylus tip and stem are nearly the same
diameter this ad ustment is critical to keep the stem from contacting a vertical surface before the tip.
This ad ustment is also convenient to ad ust parallelism when flat disc or block stylus types are used.
The range of ad ustment is very small as it is only intended to correct the stylus and spindle center line
continuity. If this ad ustment must be performed use the run-out ad ustment set-up shown above to
monitor the effect of the ad ustment. The angular alignment and run-out ad ustments are
interdependent. It will be necessary to repeat each several times to achieve significant results. When
completed, the run-out at the stylus mount end of the stylus stem should be nearly the same as the run-
out at the tip. Ad ust the stylus tip run-out last.
To check the angular alignment begin by completing the “Dialing-in” procedures for the probe tip.
Measure the run-out at the base of the stylus stem (the end away from the tip) with the dial indicator. If
the run-out is greater than the difference between the tip diameter and stem diameter then it will be
possible for the stem to contact a vertical surface before the tip (also called “shanking out”).
The angular alignment is accomplished by first performing a “Dialing-in” procedure on the stem base
using the run-out ad ustment set screws. Next, the tip is dialed-in using the angular ad ustment set
screws in the end cap of the probe. These two steps are repeated until the difference in run-out between
the tip and stem base is acceptable. Be sure all set screws are equally tight when finished.
OUTPUT SWITCH LOGIC SELECTION:
The DP-4 output is a solid state switch that can be configured for normally open or closed logic. This
choice can be specified when ordering (recommended) or can be changed in the field. The standard
configuration for the stock DP-4 is normally open. A umper block located under the mounting shank
inside the probe sets the logic. To access the umper block unplug the probe, remove the stylus, loosen
the run-out ad ustment screws and remove the mounting shank. Be careful not do damage any wires or
allow any dirt or debris inside the probe. Move the umper from its present position to the opposite end
of the three pin header to invert the logic. Use tweezers or small pliers to slide the umper block up off
the pins and then slide it down on the pins at the opposite end of the three pin header. Install the
mounting shank and snug the run out ad ustment screws. The run out ad ustment must be performed
any time the mounting shank is removed.
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INITIAL CONTROL/PROBE SETUP PROCEDURE
STEP 1: Confirm that control parameters are setup correctly for your system. The automatic
probing cycles will not work if the parameters are not correctly set. See appendix to check the default
parameter settings for the appropriate control system. Check the control operation manual if compatible
parameter settings are not found in the appendix.
STEP 2: Plug the 6' retractile cord into the DP-4 probe and into the digitizing port on the control.
The cord ends are keyed to prevent incorrect connection. At the probe end line-up the red dot with the
red painted slot on the probe connector, push the plug in until it clicks. At the opposite cord end insert
the large black connector and rotate until it drops into the digitizing port connector then finger tighten
the securing ring to seat the connector. The LED indicating light on the front of the probe should be
illuminated bright green. Touch the probe tip and the LED should turn red.
STEP 3: Press <Alt+I> to open the centroid PLC I/O diagnostic screen. Locate the inputs entered
in parameters 11 and 18. Verify that they change correctly when the probe is triggered (parameter 11)
and plugged in (parameter 18).
STEP 4:
Review the probe overtravel limits in the specifications on page 2. Perform an automatic probe cycle
test with the feedrate over ride reduced to 20% and the stylus 10 inches away from any ob ect to verify
everything is working together. Be prepared to manually stop the machine to prevent overtravel
damage to the probe. From the main screen, press <F1-Setup>, then <F1-part>, then <F5-Probing>,
then <F7-Single Axis>, <F1-Orient> to move the probe in the desired direction and finally <Cycle
Start>. The control will og the stylus in the direction of the single axis move selected. Touch the stylus
once and the control will stop and reverse travel the probe clearance amount then stop and then resume
motion in the single axis direction at the slow probe rate. Touch the stylus once and the control will
stop and display a position window. Repeat this step and ad ust parameters as needed to gain
confidence using the automated cycles.
STYLUS TIP DIAMETER CALIBRATION:
The final procedure is to calibrate your probe stylus diameter for the tool library. Although the ruby
ball (tip) diameter of the furnished styli is either 2.5mm or 5mm, entering these values in the tool
library will not produce accurate results unless they are corrected for stylus pre-travel.
Pre-travel is the amount of deflection of the stylus tip before the probe detects the surface. This value
varies depending on the length of the stylus and the speed and direction that the stylus tip is moving
when it makes contact with the surface being probed or digitized. Pre-travel variation amount should be
stated in probe specifications relative to stylus length and direction of travel limitations. A probe that
has small pre-travel variation with no restriction on stylus length and direction of travel will be quite
expensive. Machine characteristics including lash and input latency also contribute to the need to
calibrate the stylus diameter.
In order to achieve optimal results when probing or digitizing you must calibrate the tip size to
compensate for the sum of the effects previously mentioned. The following procedure is the quickest
way to determine the calibrated diameter. This procedure uses Centroid (TM) automatic probing
cycles. Consult your operation manual for similar probing cycles for your machine.
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STYLUS TIP DIAMETER CALIBRATION PROCEDURE:
STEP 1: On the mill table, fixture the precision ring gauge from the probe tool kit. The ring must
lie flat with the center line of the bore aligned with the center line of the probe stylus. Note the
diameter of the gauge.
STEP 2: Jog the probe over the center (roughly) of the ring gauge, and then slowly og the Z-axis
down until the tip of the probe is inside the bore and not touching anything.
STEP 3: From the main screen, press <F1-Setup>, then <F1-part>, then <F5-Probing>, Enter
0.00 in the field provided for probe stylus diameter and press enter, then <F1-Bore>,and finally <Cycle
Start>. The control will probe opposing walls of the bore then stop in the center of the bore. A
message box will appear on the screen that will display the measured diameter of the bore. Subtract
this number from the known diameter of the gauge bore. The resulting number will be the calibrated
diameter of the probe stylus tip.
STEP 4: Test the result. press <F5-Probing>, Enter the calibrated probe diameter in the field
provided and press enter, then <F1-Bore>,and finally <Cycle Start>. The control will probe opposing
walls of the bore then stop in the center of the bore. The message box will appear on the screen and will
display the measured bore diameter within +/- 0.0002" if the calibrated tip diameter is correct and the
machine is in good condition. Ad ust tip calibration diameter and repeat as needed.
STEP 5: Go to the Tool Library and enter the calibrated diameter for the probe stylus in the tool#
you assigned to the probe in Parameter 12.
The Probe Stylus Calibration is now complete. Your DP-4 probe is ready for probing and digitizing!
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