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Project Objectives
• This project was initiated to address the various quality and performance concerns related to the EMAX lawnmowers that have arisen during their first season in the marketplace
• From the analysis of these concerns it has been possible to identify the contributory faults and devise solutions. These solutions and implementation details are illustrated in the following slides
2
1a. Additional screw bosses to improve
switch location
Issue: Intermittent switching or no power. Lock button releases whilst in use
Status: Implemented as Type 2 on all SKUs, week 34
1c. Lock button / lever interface redesigned to
ensure positive engagement and correct
actuation of switch
1d. Additional ribs added in housing to retain lock button
when actuated
1e. Uprated lever sping to ensure
lever fully retreats upon release
1b. Lever actuator thickened to
increase rigidity
1. EMAX32 Switchbox / Handle Improvements
4
1f. In redesigning lock button / actuator interface, switching
postion has been moved earlier in stroke. More over travel
Issue: Switching point to close to handle, user needs to grip lever tightly and constantly to avoid interuptions in power supply
Status: Implemented as Type 2 on all SKUs, week 34
1. EMAX32 Switchbox / Handle Improvements
5
1g. Dimensional changes to screw bosses and
supporting ribs to secure switchboxes to handle and limit rotational movement
Issue: Switchbox not secured to handle, even though screws are fully engaged. Can cause switching problems and suggests low quality
Status: Implemented as Type 2 on all SKUs, week 34
1. EMAX32 Switchbox / Handle Improvements
6
Issue: Early transmission failures, snapped armature shafts, melting of bearing housings & belts cutting through deck
Status: Target implemetation week 44
2. EMAX32 Transmission Improvements
2a. Material change on main structural components to BMC. This gives
improvements in terms of dimensional and temperature stability. Fundamentally, it is a more rigid material which will allow a lower
belt tension, thus reducing stress on all connected components within the
transmission
7
Issue: Early transmission failures, snapped armature shafts, melting of bearing housings & belts cutting through deck
Status: Program of testing underway, target implementation week 40
2. EMAX32 Transmission Improvements
2c. Belt retenion lip increased on gear
wheel
2b. Extra grinding operation added to manaufacture of
armature shaft to ensure that assembled pinion meets run-
out specification
8
EMAX34 / 38
3. Switchbox / Handle
Improvements
4. Transmission Improvements (motor, belt, housings)
9
Issue: Intermittent switching or no power. Lock button releases whilst in use
Status: Implemented as Type 2 on all SKUs, week 34
3. EMAX34 / 38 Switchbox / Handle Improvements
3. All switchbox changes are the same as described on EMAX32
10
Issue: Early transmission failures, snapped armature shafts & belts cutting through deck
Status: Program of testing underway, target implementation week 40
4. EMAX34 / 38 Transmission Improvements
4a. Belt retenion lip increased on gear
wheel
4b. Extra grinding operation added to manaufacture of
armature shaft to ensure that assembled pinion meets run-
out specification
11
Issue: Intermittent switching or no power. Lock button releases whilst in use
Status:Implemented as Type 2 on all SKUs, week 34. Pivot location improvements week 40
5b. Pivot support location improved to ensure positive
switching over complete length of bale bar
5. EMAX42 Switchbox / Handle Improvements
5a. Internal modifications as described on EMAX
32/34/38
13
Issue: Early transmission failures, snapped armature shafts & belts cutting through deck
Status: Program of testing underway, target implementation week 40
6. EMAX42 Transmission Improvements
6a. Belt retenion lip increased on gear
wheel
6b. Extra grinding operation added to manaufacture of
armature shaft to ensure that assembled pinion meets run-
out specification
14
Standardise clip dimensions on EMAX 34
& 38 grassboxes to match those on EMAX42
EMAX 34 / 38 / 42 Grassboxes
EMAX 34 & 38 grassbox clips will be modified when production schedule allows access to mould tools.
There is no functional problem with EMAX 34 & 38 grassboxes as they are currently being produced, the modification is to standardise dimensions across all SKUs
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Implementation Summary
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Issue Affected Models Solution Proposed Implementation
Intermittent switching or no power. Lock button releases whilst in use
EMAX 32/34/38/42Redesign of internal
mechanismWeek 34
Switching point too close to handle
EMAX 32/34/38/42Redesign of internal
mechanismWeek34
Switchbox loose on handle
EMAX 32/34/38/42Modifications to screw bosses and supporting
ribsWeek 34
Snapped armatures, melted bearing housings
& belts cutting decksEMAX 32
Change material of transmission bracket
and bearing housings to BMC type material
Week 44
Snapped armatures & belts cutting decks
EMAX 32/34/38/42
Extended belt retaining lip & armature shafts to
have ground pinion mounting surface.
Week 40
Bale arm pivot can become dislocated in
housingEMAX 42
Increase are of location in pivot housing
Week 40