win- win i n s i d eW INTERTHUR

GENERATING GEAR GRINDINGGENERATING GEAR GRINDING

Infeed in mmper stroke (pass)

Infeed in mmper stroke (pass)

Feed rate in mm/Rev.

Feed rate in mm/Rev.

Shift MovementShift Movement

win- win i n s i d eW INTERTHUR

Grinding Perfect Gears: A Tough Puzzle? Grinding Perfect Gears: A Tough Puzzle?

DressingDressing Grinding WheelsGrinding Wheels

CoolantCoolantQualityetc.

Qualityetc.

MachineMachine

PerfectGears

PerfectGears

win- win i n s i d eW INTERTHUR

Causes of Gear Errors: Profile Deviations Causes of Gear Errors: Profile Deviations

win- win i n s i d eW INTERTHUR

Causes of Gear Errors: Lead ErrorCauses of Gear Errors: Lead Error

win- win i n s i d eW INTERTHUR

Causes of Gear Errors: Burning & CrackingCauses of Gear Errors: Burning & Cracking

win- win i n s i d eW INTERTHUR

Causes of Gear Errors: ConcentricityCauses of Gear Errors: Concentricity

win- win i n s i d eW INTERTHUR

- good profile form

1 1 Profile Form Profile Form

win- win i n s i d eW INTERTHUR

- diamond worn on one side- insufficent grinding allowance- insufficient amount of shifting- grit size of wheel too fine

one or two sidedone or two sided

2 2 Profile Form Profile Form

win- win i n s i d eW INTERTHUR

- unbalanced grinding wheel- spindel, workpiece out-of round- wrong change gears 3 3 Profile Form Profile Form

win- win i n s i d eW INTERTHUR

- wrong profile angle on grinding wheel- wrong value for differential change gears (AZA, NZA)

4 4 Profile Form Profile Form

win- win i n s i d eW INTERTHUR

- wobble, faulty fixturing tooling- tailstock centres damaged/faulty- workpiece spindle bearings damaged 5 5 Profile Form Profile Form

win- win i n s i d eW INTERTHUR

- unfavorable gear flank/ grinding wheel contact sequence- profile loss on wheel, shifting too small- grinding wheel too soft 6 6 Profile Form Profile Form

win- win i n s i d eW INTERTHUR

- insufficient profiling of grinding wheel- tooth profile of grinding wheel too thick

7 7 Profile Form Profile Form

win- win i n s i d eW INTERTHUR

- root relief of grinding wheel excessive

one or two sidedone or two sided

8 8 Profile Form Profile Form

win- win i n s i d eW INTERTHUR

- correct alignment

9 9 AlignmentAlignment

win- win i n s i d eW INTERTHUR

- insufficient overtravel

10 10 AlignmentAlignment

win- win i n s i d eW INTERTHUR

- grinding wheel imbalance- feed per rev. excessive- grinding spindle ouf-of round- flange damaged

11 11 AlignmentAlignment

win- win i n s i d eW INTERTHUR

- insufficient load angle compensation- error in spindle drive system

12 12 AlignmentAlignment

win- win i n s i d eW INTERTHUR

- wobble, centres, fixturing faulty- tailstock centre inprecise- workpiece spindle out-of-round 13 13 AlignmentAlignment

win- win i n s i d eW INTERTHUR

- work head inclination angle wrongly set- backlash in change gears incorrect

14 14 AlignmentAlignment

win- win i n s i d eW INTERTHUR

- wrong value for differential gears- differential gear train out-of-round

15 15 AlignmentAlignment

win- win i n s i d eW INTERTHUR

- crowning erratic on left flank due to excessive clearance between stylus and stylus bushing (non-CNC machines only) 16 16 AlignmentAlignment

win- win i n s i d eW INTERTHUR

- multi-start grindng when number of teeth divided by number of starts equals even, whole number.