VA/VE Support By HM VA/VE Support By HM Following the engineering approach ForCost Saving Customer Satisfaction

Following the engineering approach ForCost Saving Customer Satisfaction

VA/VE Support in HM

The Goal Optimize the Design & Process Increase Efficiency of process Customer Satisfaction Support to Customers Problems Less ECN Enhance Overall Profitability Establish ‘Savings Culture’ Prepare Organization for the Future Reduce Complexity

VA/VE Support in HM

Design & Process Study

Solution Analysis

Report to Customer

Time planImplement Ideas

Realize Savings

The VA/VE Implementation Process

Hero Motors

Customer Implementation

Customer Satisfaction

VA/VE Support in HM

1. HML’s design and optimization process – with a case study

2. Technical Assistance Agreement with Ricardo India.

3. HML’s Manufacturing and End-Of-Line testing facilities with emphasis on Quality Assurance.

4. HMCL’s 100 cc transmission parts under consideration and business strategy

Highlights

VA/VE Support in HM

Design Support PRO/e WF-3 Kissoft3-2008 Alias 12.02 Imageware-11 Icem srf4.3

Design Optimization

Design validation

Testing FacilityNVH Testing

Mechanical Testing

Reverse Engineering

Process Optimization

Highlights

Target setting -Transmission Design

Duty Cycle

System level Misalignment, TE

Transmission Spec

Safety factors and durability assessment of Gear, Shaft & Bearings Reliability Growth test

System level Accelerated Test

Durability test on rig

In Vehicle durability test

Transmission Design - Flow down

Based on Transmission specifications and vehicle class, detailed targets for gear, bearing and shaft durability, NVH and product testing specification were developed.

Benchmarking – To set weight and cost targets (up front in design cycle)

020406080

100120140160180

70 71 72 73 74 75 76

To

rqu

e (N

m)

CD

Torque Vs CD 72 mm CD is appropriate to transmit 100 Nm torque and can potentially meet all future variants like wider ratios, future torque increase in same engine family or sporty application.

- 6.5 Kg is set as target weight of input and out put shaft assembly with bearings.

Data :

- Seven Spur and a helical transmission for engines ranging from 790 cc to 1600 cc

- Max 1st ratio 2.9 and min 2.29

- Max 5/6th ratio 1.04 and min 0.67

Concept - transmission with Helical Gears

- All helical gears (except 1st) with varying helix angle to balance axial load on bearings and to make transmission compact.

- Module ranging from 2.475 mm to 2.0 mm with CD 72 mm for 100 Nm torque engine.- One gear is integral part of shaft in the middle to reduce gear misalignment. - Helical gears transmit higher torque with less weight along with reduced NVH

Base line NVH before optimization

Appropriate manufacturing process is selected and micro geometry parameters selected based on these results.

Hobbed gear Ground gear

Micro geometry parameters like profile crowning, slope, tip relief were chosen and optimized while applying production variations and set of torques loads on selected parameters.

Mating Gears micro Geometry Optimization

Mating Gear transmission error and effect of load sharing among teeth

Smooth and gradual load transfer from one teeth to another

Resulting smooth transmission error. As a result, tooth excitation force will be minimum while transferring torque.

NVH measurement to validate

Recommended solutions

NVH Optimization - Summary

Hero motors can study system level dynamic effects on gear trains by analyzing effects of bearing, housing, shaft on gears. This analysis guides us to optimize micro geometry to reduce effect of gear misalignment, gear dynamic effects and NVH. In one optimization loops, final results can be achieved.

Moreover, Hero motors also provide proto samples using KAPP grinding machine with universal vario dresser. This will help Customer to validate micro geometry before implementing in production and also guide customer to foresee effects of micro geometry variations on NVH during production.

End of line testing : Transmission shaft Assembly

End of line checking: Complete gear sets, shifting all gears:

Engine Power :- 67 kw at 7250 RPM

Max Torque at Input:-250Nm

Max torque at output:-1400Nm

Gear Ratio:-

High:- 0.75

Low:-0.43

Reverse:-0.35

Bevel gear –0.40 (Apply to all gear

additionally)

Specification

1010 Gear box introduction

1010 Gear box-Component

Main Shaft Assy

Counter Shaft Assy

Shifting Drum Assy

Shift Shaft Assy

Output bevel gear

Reverse Gear

Low Speed Gear

Attachment 4 Wheel DriveHigh Speed Gear

1010 Gear box-Component

Shifting Fork

810 SHO LH housing Study

Existing assy Proposed assyProposed cost saving

present cost Cost saving1.Support flange removal and modification in hsg 19.84 19.842. 2-nos screw removal (For support flange mtg) 2.63*2 5.263. 2-nos dowel pin removal (For support flange) 4.88*2 9.764. Reduce time in Assy5.Housing modification vendor feedback reqd.

Total cost saving Rs34.86/assyAnnual cost saving @30000 volume /yr 10.45 lac/yr

Support flange

screw

810 SHO LH Housing modification proposal

Existing Housing Proposed Housing

Removing these bosses For index lever mtg

For shift drum assy mtg

Relieve for intermediate gear

For index lever spring stopping

1403Gear Box study

For positive locking for shaft and plate, we can lock it by making serration into both parts Thus machining can be avoided for shaft and plate.

1403 Gear Box study

This cap can be eliminated by non machining of end of the shaft to stop coolant flowing through the shaft

1403 Gear Train-Manufacturing problem

These all picture shows possibilities of problem in mfg when considering tolerances on root diameter ,needs to be studied by Rotax and from HERO

910435230910435190

+ =New designed circlip

Rotax 991 VA/VE proposals

1.Replacing these spline bushes with split needle bearing so that Spline machining length would be reduced

Mass removing by making ring groove to be made in forging itself

They are using circlip and spline washer to restrict the gears. We have propose to use new designed circlip that will do the same functionCan be bom saving and assy time saving proposals.

1 2

P art S .

No.P roblem R oot C aus e P ropos al D-II D-III S tatus

1 M10 B low HoleE xcess machining allowance in casting

P rovide C ore hole in C asting. Yes YesC ore Pin added in D-II. Implemented

2M10 B low Hole on F ace of C ounter

E xcess machining allowance in casting

P rovide C ounter in C asting. No Yes EC R sent to Rotax. A pproval awaited.

D owel (2) B low Hole

Ø47.5 OD B low Hole

Ø8.7 - L H - B low Hole

5

4

Yes

E xcess Machining allowance in casting

No Yes

C hange R esting, C lamping & L ocating P ads in C asting & R emove E xtra Material in C asting.

E xcess Machining allowance in casting. T hroug h this c hang e we c an s ave Material, Mac hing C yc le T ime & R ejec tion of C entre H s g with R H H s g

No

Yes

No

Yes

No

R H Hous ing C omponent Des ig n C hang es

Outer R adius change to sharp edge

E C R approved by R otax.

E C R approved by R otax.

7

Ø90 B low Hole3

6 Ø8.7 - R H - B low Hole

F ace B low Hole on G asket F ace

P rovide C ore hole in C asting.E C R approved by R otax.

S olid casting change to as cas t core hole

R adius at outer profile on face. D ue to this face blow hole problem occur & parting line of insert is below the radius .

EC R send to Rotax. A pproval awaited

8

E C R A pproved by R otax.

Yes

Yes

EC R sent to Rotax. A pproval awaited

Many small chamfers & radius on F ix S ide for which C ore P ins are provided on both fix and moving s ide due to which casting frequently s tuck on F ix s ide.

E xcess Machining allowance in casting

10D ia 15.7&M14 C ore hole to be made by providing the core pin from moving s ide

B oth s ide (F ix & Moving S ide) core hole change to one s ide (Moving S ide)

Yes

9

No

F requent C asting J am in fix s ide during P roduction

1

65

2

4

3

7

9

10

8

Process Optimization