Grinding

Machines

G&NGenauigkeitsMaschinenbauNürnbergGmbH

Precision Surface Grinding MachineMPS VTG

Aus

gabe

01.

01

G&N Genauigkeits Maschinenbau Nürnberg GmbH, Wetterkreuz 35, 91058 Erlangen,Telefon: (09131) 7576-0, Telefax: (09131) 771291

E-mail: info@grinders.de, Internet: http://www.grinders.de

Operating Manual

General

This directive is intended for personnel response to operate the grindingmachine.

The complete technical documentation shall all the times be kept near thegrinding machine.

Thie operating directive points out essential details for the application of thegrinding machine.

With hints contained in this directive, failures at the grinding machine may beavoided thus permitting troublefree operation. It is therefore of utmostimportance that personnel delegated to operate the machine is familiar withthis directive, especially the chapter for safety.

It is recommended to carefully study the directive prior to taking machine tooperation, as G&N will not come up for damages or operating failures resultingfrom nonobservance of this directive.

Note:

Technical modifications serving for improvement of the grinding machine aresubject to exception as compared to description and notes of this directive.

Purpose of Machine:

The precision grinding machine MPS VTG is exclusively designed forresharpening punching tools made of steel.Any other application is considered contrary to intended purpose.The manufacturer will not accept claims for damages resulting fromsuch use; the user will be responsible for such application.

Precision Surface Grinding MachineMPS VTG

SPECIFICATION

Order No.: _______________

Mfg. Year: _______________

El. Connection V/Hz: _______________

2001

440V50Hz

Connected Load 4 kVAGrinding Motor: 3,3 kW

440V50Hz2850 min -1

Grinding Wheels

CBN ø 200X34X32 mmDiamant ø 200X34X32 mm

Precision 0,005 mm

Rotary Table ø 320 mm

Max. grinding height: ca. 300 mm

Space (depending on order) ca. 760 x 650 mm

Noise level < 67dB(A)

Weight ca. 300 kgs

TECHNICAL DATAMPS VTG

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Contents directory

1 Safety ............................................................................. 11.1 Safety indicators ......................................................................... 1

1.1.1 Warning symbols ................................................................................. 11.1.2 Attention-indicator ............................................................................... 1

1.2 Compliance stipulated operation ............................................. 21.3 Approved personnel .................................................................. 21.4 Fundamental safety indicators ................................................. 21.5 Especial type of danger; electricity ......................................... 41.6 Self-made modifications ban .................................................... 41.7 Environmentally friendly disposal .......................................... 4

2 Unpacking, installation and commissioning................... 52.1 Unpacking the MPS VTG ........................................................... 52.2 Transport to installation site ..................................................... 52.3 Installation.................................................................................... 7

2.3.1 Installation site ..................................................................................... 72.3.2 Installation ............................................................................................ 7

2.4 Connecting and commissioning .............................................. 72.4.1 Electrical connection ........................................................................... 72.4.2 Coolant system .................................................................................... 92.4.3 Grinding wheel ..................................................................................... 92.4.4 Rotary table and workpiece clamping devices. ................................ 92.4.5 Commissioning .................................................................................... 9

3 Manual operation of the MPS VTG .............................. 103.1 Operating elements front plate ............................................... 103.2 Stepcon operating panel ......................................................... 11

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3.3 Switching the machine functions manually .......................... 133.3.1 Machine main switch, EMERGENCY switch .................................... 133.3.2 Preselection Manual/ Automatic ....................................................... 133.3.3 Spindle On/Off .................................................................................... 133.3.4 Rotary table On/Jog ........................................................................... 133.3.5 Automatic start ................................................................................... 143.3.6 Emergency return .............................................................................. 143.3.7 Grinding spindle infeed ..................................................................... 14

4 Automatic mode ........................................................... 154.1 Programming the grinding cycle............................................ 154.2 Clamping the workpiece .......................................................... 174.3 Setting of the switch-over point .............................................. 18

4.3.1 The touch-grind control .................................................................... 184.3.2 Setting ................................................................................................ 19

4.4 Grinding cycle ........................................................................... 204.4.1 Work sequence .................................................................................. 204.4.2 Error codes ........................................................................................ 21

5 The touch-grind control ................................................ 235.1 Components .............................................................................. 235.2 Setting the touch-grind control .............................................. 24

6 Rotary table .................................................................. 276.1 Description ................................................................................ 276.2 Rotary table angel setting (sine table) .................................... 276.3 Tool fixturing ............................................................................. 28

7 Grinding wheels ........................................................... 297.1 Types .......................................................................................... 297.2 Mounting schematic ................................................................. 297.3 Replacing the CBN grinding wheel ........................................ 307.4 Sharpening the CBN grinding wheel ..................................... 31

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8 Maintenance ................................................................. 338.1 Motor and spindle..................................................................... 338.2 Rotary table ................................................................................ 338.3 Fine-infeed ................................................................................. 338.4 Grinding wheelhead guideways ............................................. 33

9 Appendix ...................................................................... 359.1 Machine elements ..................................................................... 359.2 MACHINE DATA menu .............................................................. 379.3 TEST INPUT menu .................................................................... 39

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ATTENTION

1 Safety

1.1 Safety indicators

1.1.1 Warning symbols

These symbols are found within this operating manual as occupa-tional safety indicators wherever a danger to personnel life or limbexists. They are individually classified as follows:

DANGER!

Non observance of this indicator LEADS to massive bodily harm ordeath. Heed exactly the stipulated rules of conduct accompanyingthis indicator/symbol!

WARNING!

Non observance of this indicator CAN LEAD to massive bodily harmor death. Heed exactly the stipulated rules of conduct accompanyingthis indicator/symbol!

CAUTION!

Non observance of this indicator can lead to minor injuries or materi-al damage. Heed the stipulated rules of conduct accompanying thisindicator/symbol!

Heed these indicators and in these cases always conduct yourselfwith care. Also inform other operators of these occupational safetyindicators. Further to the indicators found in this operating manual itis also important to heed the general safety rules and rules for theprevention of accidents.

1.1.2 Attention-indicator

The indicator ”Attention” is found in all places in the operating manu-al where something must be especially heeded to ensure adherenceof guidelines, specifications, indicators, and that the operations arecorrectly processed, as well as preventing damage and/or destruc-tion to the machine and/or to other system parts.

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1.2 Compliance stipulated operation

The MPS VTG grinding machine is designed for resharpening hard-ened steel punching dies.

Using the machine for other applications is considered as noncom-pliance stipulated. The manufacturer is not liable for any damageresulting from such a case and the risks therein will be borne solelyby the operator.

1.3 Approved personnel

The MPS VTG grinding machine is built to state-of-the-art and isoperationally safe. Nevertheless this machine can be a danger to lifeand limb of operators or third parties when used incorrectly or byuntrained personnel or for noncompliance stipulated applications.

Every person in the operator’s company engaged with any of thefollowing; setup, installation. Operation, maintenance and service ofthe MPS VTG grinding machine is obliged to have read and under-stood the operating manual and especially the chapter ”Safety”. It isrecommended that the operator has his personnel confirm havingdone so in writing.

1.4 Fundamental safety indicatorsn The grinding machine may only be operated, serviced andmaintained by authorized, trained and schooled personnel. Thesepersonnel must have received a special schooling regardingpossible dangers.

n Responsibilities regarding setup, maintenance and repair ofthe grinding machine must be clearly defined and heeded in orderto hinder, with regards to safety, any incompetent handling.

n Working with the electrical equipment may only be carried outby qualified specialists.

n The EMERGENCY STOP SWITCH must be switched off in anysituation requiring that the machine functions be immediatelyswitched off.

n Don't remove or modify any parts of the safety equipment!

n Grinding wheels may only be mounted by reliable and experi-enced personnel who, while doing so, heed the regulations foundin this operating manual!

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n Sharpening or dressing of the grinding wheel may only takeplace using the respective fixtures (never by hand).

n Only use grinding wheels that have been tested and are ap-proved for the grinding spindle rpm!

n The grinding wheel must be tested for freedom of motion afterany setup or maintenance work!

n Test the grinding wheel for freedom of motion prior to switchingon the grinding spindle!

n Any mode of operation which could impair the safety of thegrinding machine is prohibited!

n The operator is responsible for ensuring that no unauthorizedpersonnel works on the grinding machine.

n The operator is obliged to inspect the grinding machine, atleast one time per shift, for externally noticeable damage or de-fects. Any changes that have occurred (including operationalbehavior) must be notified immediately to the relevant depart-ment!

n The operating company is obliged to ensure that the grindingmachine is only used when it is in perfect running condition!

n The operating company is obliged to ensure, by means ofsuitable directives and inspections, that the working area, at andaround the grinding machine, is kept clean and uncluttered!

n A categorical rule is that no safety device may be dismountedor set such that it no longer functions. If it is necessary to deacti-vate/disassemble a safety device in order to setup, repair ormaintain the machine, then the safety device must be immediatelyreactivated/assembled upon completion of said setup, repair ormaintenance!

n Prior to beginning such work on the grinding machine, ensureno drives or auxiliary devices can inadvertently be switched on!Lock the main switch using a padlock.

n The local safety and accident prevention regulations are alsovalid and must in every case be heeded when operating the grind-ing machine.

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1.5 Especial type of danger; electricityn Work on electrical systems may only be carried out by qualifiedelectricians!

n Prior to opening the electrical cabinet switch the main switch offand secure with a padlock!

n Prior to assembly work de-electrify the electrical cabinet bydisconnection of the power supply!

n The built-in safety devices (e.g. ground resistance) must bechecked after respective electrical assembly work or maintenance.

n The machine’s electrical equipment must be regularly inspectedand/or tested. Defects such as loose connections, braised cables,etc. must be immediately fixed!

n VDE-regulations as well as the local energy supply companyregulations must be observed and heeded!

n Only use originally supplied fuses with the specified amperagevalues!

1.6 Self-made modifications ban

n Self-made modifications and changes that could affect thesafety of the grinding machine are not allowed.

n Do not make any modifications and changes that could affectthe safety of the grinding machine, without prior permission of themanufacturer! This is also applicable to assembly and settings on/to safety devices and valves.

1.7 Environmentally friendly disposalEnsure that operating and auxiliary materials are disposed of safelyand in an environmentally friendly manner!

Be sure to heed local government regulations!

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2 Unpacking, installation and commissioning

2.1 Unpacking the MPS VTG

The MPS VTG comes delivered bolted to a palette.

Remove the protective foil and loosen the clamping bolts.

Dispose of the packaging material as per local government regula-tions.

Inspect the MPS VTG for any damage that may have occurred duringtransport and report to us immediately if any damage is found.

Check that the enclosed standard and special accessories conformwith the delivery note and packing list.

All bare metal machine parts have been greased to protect againstrust. This protective grease must be removed using a cleaning clothand, if necessary, with the addition of some petroleum.

CAUTION!

Benzine or trichlorethylene (Tri) are not suited for cleaning!These materials are unhealthy and remove all traces of grease(danger of rust).

2.2 Transport to installation site

The best way to transport the machine to the installation site is with asuitably sized forklift (machine weight approx. 300 kgs).

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Use the forklift as shown in Illustration 1.

CAUTION!

Take care when lifting the machine thatno cables or hoses get squashed.

Illustration1: forklift position

Illustration2: siting diagram

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2.3 Installation

2.3.1 Installation site

Place the MPS VTG in an area which has sufficient light and space(see Installation diagram Illustration 2). The installation site may notbe near any vibration inducing machines and must be on a levelground with sufficient load carrying capacity.

The MPS VTG must be connected to an electrical supply accordingto the data plate of the machine (clockwise rotational field).

2.3.2 Installation

Place the machine exactly horizontal by adjusting the vibration damp-ers (Illustration 3) and check using a spirit level.

2.4 Connecting and commissioning

2.4.1 Electrical connection

WARNING!

Dangerous electrical voltage! Possibility of severe or deadlyinjury.

Switch off the power supply and secure it against unautho-rized switching on when doing any work on the electricalsystem.

Illustration 3: vibration dampers

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When connecting the machine observe the VDE-regulationsas well as the local energy supply company regulations.

Check the supplied safety measures (e.g. measure the groundresistance) after connection.

The MPS VTG has been set at the manufacturing factory to connec-tion values found on the data plate. Connecting the machine to apower supply system with deviating values is not always possible. Ifsuch a case arises please contact G&N in order to clarify necessarymeasures.

The MPS VTG is delivered with ready to use mounted connectionline and plug. You must check the rotation direction of the grindingmotor during set up.

Switch the electricity back on and check the rotational direction ofthe spindle motor ( arrow on the grinding wheel guard). If the rotation-al direction does not correspond with the arrow, then the rotationaldirection is easily corrected by exchanging two or three positions ofthe power supply connectors (L1, L2, L3).

CAUTION!

The motor terminal connections may not be changed.This could cause damage to the MPS VTG.

Illustration 4: electrical connections

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2.4.2 Coolant system

The coolant container is found in the machine base. The coolant isconveyed through the center of the grinding wheel (through hollowspindle). The amount of coolant is regulated using the ball valvefound to the left of the machine housing.

The coolant system has been finish assembled and connected at themanufacturer’s factory. We recommend though that the hose linesare checked for damage and tightness prior to commissioning.

Fill the coolant container with water and coolant additive (e.g. ARALMultrol).

2.4.3 Grinding wheel

The grinding wheel is already mounted and ready to run.

2.4.4 Rotary table and workpiece clamping devices.

The workpiece clamping device assembly as well as the setting therotary table are described in chapter 6.

Select the most suited workpiece clamping fixture and assemble itas stated in the operating manual.

Set the rotary table as stated in the operating manual.

The MPS VTG is now correctly connected.

2.4.5 Commissioning

All operating elements are found on the front side of the electricalcabinet (see Chap. 3).

Switch the main switch (EMERGENCY switch) to ON

The MPS VTG is now ready to run.

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3 Manual operation of the MPS VTG

3.1 Operating elements front plate

ON/OFF

Stepconpanel

Emergencyreturn

Automaticstart

PreselectManual/Auto

Rotary tableOn/Jog

SpindleOn/Off Emergency Stop

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esc.

Del.

17

8 2

9 3

3.2 Stepcon operating panel

By pressing the 17 keys the grinding wheelhead feeds-in, alterna-

tively retracts in increments of 5 µm.

By pressing the 8 2 keys the grinding wheelhead feeds-in slowly,alternatively retracts slowly.

The speed can be set in the menu MACHINE DATA (See Chap. 9).

By pressing the 9 3 keys the grinding wheelhead feeds-in quickly,alternatively retracts quickly.

The speed can be set in the menu MACHINE DATA (See Chap. 9).

The keys are only effective after pre-selecting “manual”.

During data entry the last shown figure in the display is erased whenthis key is pressed. Thus the displayed value can be completelyerased.

The currently selected menu can be exited by pressing the ESC key.

The previous menu is automatically displayed. If data has been al-tered, then the data will first be checked.

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F1

F3

F2

?

The menu program will be displayed by pressing the PROGRAMSELECT key.

NEXT

Press the key to scroll through the program sets 1 - 5

ENTER

The displayed value, alternatively a display of possible selections,will be confirmed by pressing the ENTER key.

During data entry the shown value in the display is erased when thiskey is pressed. Thus the displayed value can be completely erased.

SET UP

Use SET UP to set a specific value on the fine downfeed scale.

Example: Set the workpiece surface to the value "0"

n preset mode manual;n clamp workpiece;n move the grinding head carefully down until the grinding wheel

touches the workpiece slightly;n press key F1;

n erase displayed value with ? ;

n enter "0"

Now the workpiece surface is set to value "0"

INPUT/OUTPUT TEST

The input/output test is invoked by pressing the F2 key.

MACHINE DATA

The menu is invoked by pressing the F3 key. (Enter password:9876).

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3.3 Switching the machine functions manually

3.3.1 Machine main switch, EMERGENCY switch

Turn the switch clockwise to turn the machine on.

n The machine is ready-to-operate.

EMERGENCY STOP

Press the switch in all situations requiring that the machine functionsbe immediately stopped.

Turn anticlockwise to release.

3.3.2 Preselection Manual/ Automatic

Switch in “Manual” setting

n The MPS VTG functions (spindle, rotary table, infeed) can bemanually operated.

Switch in “Auto” setting

n The MPS VTG is in automatic mode

3.3.3 Spindle On/Off

If “Manual” has been preselected

Press the button to turn on the spindle motor.

This turns on the coolant motor simultaneously.

Pressing the button again turns off the spindle motor.

3.3.4 Rotary table On/Jog

Switch in middle setting

n Rotary table is switched off

Switch in “On” setting

n Rotary table rotates at preselected rpm

n An proximity switch ensures that the rotary table remains stand-ing in its base position when switched off.

Switch pressed to “Jog” setting (switch does not lock in)

n Rotary table rotates as long as the switch is held

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3.3.5 Automatic start

Manual mode preselected:

After pressing the key the grinding head is downfed to the switchover point (+GAP) and stopped then. (Function is used to calibratethe touch grind control).

Automatic Mode preselected:

Pressing the key starts the automatic grinding cycle.

3.3.6 Emergency return

Press this button in order to interrupt the current grinding cycle.

n The grinding spindle moves to its initial position, then

n rotary table, spindle motor and coolant are switched off.

3.3.7 Grinding spindle infeed

Press the 71 keys

The grinding wheelhead feeds-in, alternatively retracts in incrementsof 5 µm.

Press the 82 keys

The grinding wheelhead feeds-in slowly, alternatively retracts slowly.

The speed can be set in the menu MACHINE DATA.

Press the 93 keys

The grinding wheelhead feeds-in quickly, alternatively retracts quick-ly.

The speed can be set in the menu MACHINE DATA .

The keys are only effective after pre-selecting “Manual”.

71

82

93

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4 Automatic modeGrinding in automatic mode comprises of the following steps:

1. Programming of the grinding cycle

2. Clamping the workpiece

3. Setting of the switch-over points

4. Grinding cycle

5. Workpiece removal

4.1 Programming the grinding cycleThe following values can be varied/selected in the grinding cycle:

n Roughing amount

n Roughing speed

n Finishing amount

n Finishing speed

n Sparkout time

The values are entered using the Stepcon panel.

You can enter up to five different program cycles.

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Entering the values

Press the key

Press the key ESC to close the menu; the entered data will be adopt-ed.

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4.2 Clamping the workpiece

Workpiece clamping is described in Chapter 6.

First select the required workpiece fixture and mount it on the rotarytable.

Set the required rotary table angle.

Carefully clamp the workpiece.

CAUTION!

Ensure that the workpiece is correctly clamped.Danger of injury due to parts being ”thrown out”.

A B

CD

C

Illustration. 5: Workpiece fixtures AMADA ®- System (selection)A: Matrices; B: Punch A; C: Punch B; D: Punch E

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4.3 Setting of the switch-over point

4.3.1 The touch-grind control

Guide rail

Support

Lock

Endstop for proximityswitch

Measuring plate

Proximity switch

Endstop

Safety switch

Lock screw

Illustration 6: Touch grind control

Illustration 7: proximity switch

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4.3.2 Setting

CAUTION!

The touch-grind control must be set correctly because themachine may be damaged due to the grinding wheel runningonto the workpiece.

CAUTION!

The touch-grind control must be reset every time the grindingwheel is changed or if the grinding wheel has worn down by anoticeable amount (See Chap. 5).

Precondition: grinding wheel head in start position!

1 Swivel the measuring plate over the workpiece

2 Loosen the clamp and lower the measuring plate down until ittouches the workpiece. Pull the clamp lever to lock.

3 Swivel back the measuring plate completely (monitored bysafety switch)

The switch-over point is now set.

The switch-over point must be newly set for each workpieceATTENTION

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4.4 Grinding cycle

Set select switch to AUTO, you will be asked to select a grindingprogram (scroll with key NEXT, confirm with ENTER).

The selection of a grinding program is only possible afterswitching from MANUAL to AUTO . If you want to change togrinding program between to cycles, first switch from AUTO toMANUAL and back.Editing of the grinding Programs is only possible at MANUAL.

4.4.1 Work sequence

Press AUTO START

1. The grinding wheelhead moves in rapid motion until reachingthe switch-over point.

Message: Engaging punch

2. Reaching switch-over point (= triggering of the touch-grindswitch-over point proximity switch) the infeed speed is switchedfrom rapid to the GAPE speed. Now the grinding head movesdown the GAPE distance. Then the grinding spindle, coolantmotor and the rotary table are started as well as slowing the Gapespeed to roughing infeed speed.

Message: Stock removal

3. Roughing cycle changes, after the programmed stock removalamount, to the finishing speed.

Message: Stock removal

4. Finishing cycle changes, after the programmed stock removalamount, to the spark-out cycle.

Message: Stock removal

5. Sparkout.Message: s

6. The grinding wheelhead lifts by the entered amount.Message: Lift off

7. Retracts to the start position.Message: Retract .

If the grinding cycle does not start , not all preconditions are fulfilled.

ATTENTION

shining

shining

blinking

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4.4.2 Error codes

NO WKP

The proximity switch of the touch grind control was not actuatedbefore pressing key AUTO START.

Set switch over point and press AUTO START again.

DOOR OPEN

The proximity switch of the sliding door was not actuated beforepressing key AUTO START.

Close door and press AUTO START again

GAP LOW

Grinding head position too low (below switch over point).

Switch to MANUAL and move grinding head up until the proximityswitch gets clear.

PUNCH ACTIV

Grinding head position too low (below switch over point).

Switch to MANUAL and move grinding head up until the proximityswitch gets clear.

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5 The touch-grind controlThe touch-grind control is used to set the switch-over point fromrapid motion speed to rough grinding speed in automatic cycle.

5.1 Components

Illustration 9: proximity switch

Endstop

Proximity switch

Guide rail

Support

Lock

Endstop for proximityswitch

Measuring plate

Safety switch

Lock screw

Illustration 8: Touch grind control

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5.2 Setting the touch-grind control

When setting the touch-grind control, the underside of the measuringplate must be placed at an exactly defined height to the lowest edgeof the grinding wheel.

The touch-grind control must be newly reset after every grindingwheel change or wheel dressing as well as if there is any noticeablewheel wear.

1. Select MANUAL.

2. Drive the grinding wheelhead upwards until you can swivel inthe touch grind control.

3. Clamp master workpiece.

4. Swivel in the touch grind control, loose the lock, then lower thetouch grind control until the measuring plate touches the work-piece. Then thigten the lock again and swivel back the touch grindcontrol.

5. Remove the master workpiece.

6. Press key AUTO START (still MANUAL mode).The grinding head moves fast down until the proximity switch istriggered. Now the infeed speed changes to slow, infeed continu-ous until the proximity switch is released again. Then the infeedstops.

7. Press key F1 SET UP and set the actual position to zero.

8. Clamp master workpiece again. Move grinding head up ifnecessary.

9. Move the grinding head carefully down until the grinding wheelslightly touches the workpiece.

10. Note the infeed displayed at the stepcon.

11. Loose the clamping screw and turn the measuring plate ac-cording to the displayed infeed amount. Keep in mind that thedistance workpiece to grinding wheel at the switch over pointmust be 200µm.

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Examples:

Displayed value 500µm = measuring plate too low.Adjust measuring plate 300µm higher.

Displayed value -500µm = measuring plate too high.Adjust measuring plate 700µm lower.

CAUTION!

200µm distance between grinding wheel and workpiece at theswitch over point!

After adjustment thighten clamping screw again.

12. Check correct adjustance.

a. Clamp workpiece;

b. Set switch over point

c. Select MANUAL and press AUTO START until proximityswitch is triggered.

d. Check whether distance grinding wheel – workpiece iscorrect (200µm).

e. Adjust distance if necessary.

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6 Rotary table

6.1 Description

The rotary table is designed for mounting of workpiece clampingfixtures up to a diameter of 320 mm.

The rotary table rotational speed is set at 30 rpm. The rotary tablealways stops in defined position due to a built-in proximity switch andcam.

6.2 Rotary table angel setting (sine table)

In order to grind workpieces with a taper, the rotary table can betilted up to 12° from the horizontal position.

For this purpose the rotary table is hinged with bearings on one side.The angle is set by turning an infinitely variable eccentric disc (withangular scale) mounted on the rotary table.

1 Loosen the clamping screw with an allen key

2 Turn the eccentric disc until the required angle correspondswith the mark on the base plate (it is sometimes necessary toslightly raise the rotary table on the side).

3 Retighten the clamping screw

Clamping screw

Eccentric disc

Illustration 10: Eccentric disc rotary table

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6.3 Tool fixturing

look at the special operating instruction

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Special nut with coolantdistributor nozzle, SW 24

7 Grinding wheels

7.1 Types

The MPS VTG is basically designed for using CBN grinding wheels.

The supplied CBN grinding wheel has proven to be very good forgrinding hardened tool steels.

As an alternative diamond grinding wheels can also be used where-by the mounting and sharpening processes are the same as thosefor CBN grinding wheels.

7.2 Mounting schematic

4 allen screws

M5 x 20 DIN 912

(allen key Nr. 4)

Counter flange

Flange

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7.3 Replacing the CBN grinding wheelThe grinding wheel must be replaced if damaged or it is too worndown (< 0.5mm) to be used.

CAUTION!

Prior to replacing the grinding wheel ensure that the mainswitch is switched off and that it can not be inadvertentlyturned on. Padlock the main switch.

Obey the following:

1. Move grinding head upwards.

2. Loosen special nut with distributor nozzle (SW 24) (left-handthread!). As counter pressure stick in the supplied open-jawedwrench SW 24 above the grinding wheel.

3. Pull the grinding wheel off the spindle using the supplied draw-ing-off tool.

4. Disassemble the grinding wheel flange by loosening the allenscrews with an allen key and remove the grinding wheel.

5. Mount a new grinding wheel and screw the flange back togeth-er.

6. Pushing lightly by hand mount the grinding wheel flange backonto the grinding spindle. It is of utmost importance to avoidmounting the flange to the spindle taper with too much force!

7. Retighten the special nut with distributor nozzle.

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Heed the following indicators precisely:

n Grinding wheel assemblies may only be mounted by reliableand experienced personnel.

n It is extremely important that the internal taper of the grindingwheel flange and the spindle taper are absolutely clean beforemounting the grinding wheel assembly.

n When mounting the grinding wheel assembly great care mustbe taken to ensure perfect runout.

n Even the smallest of foreign bodies between the two mountingsurfaces can cause runout and, if once pressed in, can only becorrected with great difficulty. Damage of this type can only becorrected by very careful scraping.

7.4 Sharpening the CBN grinding wheel

After mounting a new CBN grinding wheel it must be sharpened,alternatively be re-sharpened after being used for a long time.

Resharpening is necessary when the CBN bonding has closed-up orbecome smooth due to high loading or grinding of difficult workpiecematerials.

The residue clinging to the bonding can be removed using the sup-plied sharpening tool.

Bolt the base plate to the rotary table as you would a die.

ATTENTION

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Follow these instructions:

1. Mark the grinding wheel bond with a felt tip pen

2. Clamp the sharpening tool

3. Select automatic; enter sharpening data

4. Determine the switch over point

5. Start automatic cycle.

6. At the end of the automatic cycle, using a mirror, check if thefelt tip marking has been ground off. If necessary repeat thedressing process.

7. Remove sharpening tool.

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8 MaintenanceIncluded in the scope of supply of the MPS VTG is a grease gun tolubricate the fine-infeed and the grinding wheelhead guideways. Usecommercially available bearing grease for lubricating.

8.1 Motor and spindle

Motor and spindle are maintenance free.

8.2 Rotary table

The rotary table has no lubrication points.

8.3 Fine-infeed

Lubricate the fine-infeed screw spindle every 100 working hours or 2 weeks with grease using the supplied grease gun.

1 Switch the machine main switch to "OFF".

2 Unscrew the machine's rear panel.

3 Using the grease gun apply a little grease to the marked lubri-cation points (see sticker).

4 Screw the machine's rear panel back on.

8.4 Grinding wheelhead guideways

There are lubrication points on the grinding wheelhead guideways.

Lubricate every 100 working hours or 2 weeks with grease using thesupplied grease gun.

1 Drive the grinding wheelhead upwards, until the proximityswitch is triggered.

2 Remove the stoppers out of the lubrication holes to the left andthe right of the grinding area (see sticker).

3 Apply a little grease using the grease gun to each of the lubri-cation holes on the grinding wheelhead guideways.

4 Press the stoppers back into the lubrication holes.

5 Drive the grinding wheelhead back downwards.

MPS VTG

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OPERATING MANUAL

MPS VTG

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OPERATING MANUAL

Rotary table

Main switch

9 Appendix

9.1 Machine elements

Coolant tankwith pump

Fine-infeed

Motor

Touch-grindcontrol

Grinding wheelguard

StepconSignal lamp

EmergencyStop

MPS VTG

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OPERATING MANUAL

MPS VTG

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OPERATING MANUAL

9.2 MACHINE DATA menu

The machine initial settings are stipulated in the MACHINE DATAmenu.

The menu is password protected.

The parameters programmed by G&N prior to delivering themachine have been optimized and should not be changedwithout a compelling reason.

Press F3

ATTENTION

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OPERATING MANUAL

MPS VTG

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OPERATING MANUAL

9.3 TEST INPUT menu

The machine switch functions can be tested in this menu.

Press F2

Position Switch

1 Hand/Auto

2 Auto Start

3 Spindle

4 Rotary table

5 Touch-grind control contact

6 Rotary table end contact

7 WKP

8 Emergency return

E1 Proximity switch1 (upper)

E2 Proximity switch2 (lower)

MPS VTG

OPERATING MANUAL