Clutch Selection

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					          Clutch Selection
for American Marine Z-drive Product




              Submitted to:
   The Faculty of the MSETM Program
       Oklahoma State University
             Stillwater, OK




            Submitted by:
            Phillip Magee
            Stillwater, OK




           Date Submitted:
             July, 2004


                                      Page 1 of 32
EXECUTIVE SUMMARY

The dog clutch has been chosen for use in the new z-drive concept as a primary forward,
neutral, reverse clutch, and gear selector. The value based product will only contain the
dog clutch while the premium product will also have an optional wet disk master clutch
on the engine for decoupling torque during shifting and greatly improving shift
aesthetics.

Clutch type selection and drive-line configuration is necessary early in the new z-drive
project in order to set basic design direction. Using the dog clutch in the base product will
enable American Marine to maintain current costs on value based products while
providing a safe, robust, and reliable clutching mechanism. The ability to add an optional
wet disk master clutch to the dog clutch, for decoupling torque during shifting, will
provide the best shift aesthetics in the industry and give American Marine the ability to
satisfy the desires of the growing market of discriminating boating customers without
sacrificing safety, robustness, or reliability.

Dog, cone, wet disk, dry disk, and band clutches were investigated. Magnetic clutches,
belt clutches, sprag clutches, spring clutches, and torque converters were also
brainstormed as clutch alternatives. These clutches were analyzed in several drive-line
configurations. Single cone and dog clutch systems were discussed along with
synchronized dog clutches. Wet and dry master clutches with dog clutch gear selectors
were also analyzed along with a torque converter and cone clutch combination.

Clutch types and drive-line configurations were analyzed using benchmarking, energy
trance and barrier diagramming, preliminary hazard listing, preliminary hazard analysis,
and decision analysis. The benchmarking simply listed the major clutch alternatives and
their current or past applications. The energy trace and barrier diagramming supported
the need for a focus on design safety in the clutch. The preliminary hazard list presented
the available hazards of a clutch. The preliminary hazard analysis ranked each failure
mode of each clutch type to determine the least hazardous clutch type. The decision
analysis set and weighted criteria for judging overall clutch function and ranked each
clutch according to the criteria. This process also used estimated costing of each clutch
and drive-line configuration to evaluate the value of each alternative. This overall
process highlighted the safe and cost effective design characteristics of the dog clutch.
The process also revealed that the wet disk clutch is needed to achieve the improved shift
aesthetics in the new z-drive project. A modular approach that utilizes the dog clutch for
a base product and an optional master wet disk clutch for refined premium drive systems
was the final outcome of the knowledge gained from the processes in this project.

A prototype of the premium system has been built and is proving to provide undetectable
shift events. The team is working to define proper sizing and control components. A
design concept with working prototype and detailed costing information will be available
by December 17, 2004 with current project funding ($250,000). This will satisfy the
current approved project schedule by preparing for the new z-drive product
implementation process prior to January 1, 2005.


                                                                                Page 2 of 32
INTRODUCTION
This project was conducted as a set of engineering processes used to provide information
in order to drive a decision on the type of clutch to be used in American Marine’s new z-
drive product line.

The project purpose is discussed first in order to establish the need for the project and
how it fits into American Marine’s strategy. Then the project’s approach is described and
the engineering procedures are explained. A listing of the alternative clutch types
considered and their source is also included. The analysis and results make up the
majority of this project report.

Each of the following engineering processes used will be discussed in detail.
First, a benchmarking exercise is used to document clutch types that are readily available.
Next, and energy trace and barriers diagram (ETBD) is explained. Then, a preliminary
hazard list (PHL) clearly lists opportunities for clutch failures. Once the PHL is
complete, a preliminary hazard analysis uses failure modes and effects analysis on a
generic clutch and on selected clutch types. A decision analysis that follows the value
analysis / value (VA / VE) engineering procedure is utilized last.

Finally, conclusions and recommendations generated from the above processes are
clearly stated. Clutch type selections are made and the recommendations for further
development are defined.

Appendixes A through E contain actual data from each engineering process used in
clutch selection.
                Appendix   A       Benchmarking Exercise
                           B       Energy Trace and Barriers Diagram
                           C       Preliminary Hazard List
                           D       Preliminary Hazard Analysis (FMEA)
                           E       Decision Analysis

PROJECT PURPOSE
This project’s purpose was to select a clutch type to be used in a new z-drive design for
American Marine. The new z-drive project is currently in the conceptual phase. The
American Marine research and development team is scheduled to complete concept
development by December 17, 2004. Clutch type selection has been completed and is a
major decision that must be made in z-drive design. The type of clutch selected highly
influences overall safety, manufacturability, reliability, and durability of the z-drive while
dictating noise, vibration, and harshness characteristics.




                                                                                Page 3 of 32
American Marine designs and produces z-drive engine packages for the recreational and
light commercial marine markets. These engine packages utilize an automotive based
engine with marinized cooling, exhaust, and electrical systems. The powertrain of the z-
drive package transmits the rotational power from the engine to the propeller. The z-drive
also steers the propeller for directional control and trims the propeller by changing its
angle to vector the propeller thrust force. Trimming improves vessel acceleration and top
speed. The z-drive power system also provides shifting in forward, neutral, and reverse.
One last major function of the z-drive powertrain is to tilt the propeller up for trailering of
the vessel.

The z-drive product at American Marine currently consists of two lines of z-drive
propulsion systems. The Charlie product is used on four cylinder, V6, and small block V8
engines from 130 horsepower to 300 horsepower. This z-drive is currently offered with a
single propeller in several gear ratios for different engine sizes and boat weights. The
basic Charlie z-drive design has been in production since 1965 with evolutionary
development and feature additions. The second z-drive product line is the Delta z-drive.
This product is used on V6, small block V8, and big block V8 engines from 230
horsepower to 575 horsepower. There is a matrix of product line extensions for the Delta
z-drive. This drive is offered in single propeller sport (Delta I), single propeller low speed
(Delta II), and dual propeller sport (Delta III) versions. These versions are offered in
standard, Diesel X, Performance X, and Racing XR versions. Several gear ratios are
provided for each z-drive to optimize performance in different boats with each engine
option.

The z-drive driveline is very simplistic and robust. In the past, great attention has been
made to ensure that the American Marine z-drives are the most durable and reliable z-
drives on the market. Customers have demanded durability and reliability in the
recreational and light commercial marine engine markets. Historically, product esthetics
that deal with NVH (noise, vibration, and harshness) have been on the customer delight
level. The shift systems in the current Charlie and Delta z-drive products do not address
NVH issues well. Recently, customers have become more sensitive to NVH issues. 2002
and 2003 J.D. Power surveys have scored the American Marine z-drive products below
Volvo z-drives in NVH characteristics. Volvo z-drives are currently the only major
competitive z-drive product.

American Marine has approved a program to design and develop new z-drive products to
replace the current Charlie and Delta z-drives. The development of new z-drives allows
consideration of new clutch mechanisms to address customer NVH desires to a level that
the current clutch and gear selection mechanisms can not achieve.

This project is a small, but critical component of the new z-drive program and has
provided the basic building blocks to design the new z-drive. The proper selection of the
clutch component is crucial in the success of the entire new z-drive program and the long
term competitiveness of American Marine in the future z-drive marketplace. This project
has successfully selected a clutch type and configuration to be used in the new z-drive




                                                                                 Page 4 of 32
concept. Modeling, analysis, and prototype construction has started in order to investigate
the z-drive concepts based on the clutch configuration chosen in this project.

APPROACH

Process Flow Chart –          The following five processes were used in the clutch types
                              and driveline configuration selection.

                    Benchmarking Exercise


              Energy Trace and Barriers
              Diagram (ETBD)


              Preliminary Hazard List (PHL)


              Preliminary Hazard Analysis
              (PHA)

              Decision Analysis (VA / VE)


Each process builds upon the overall knowledge of the clutch in order to provide data for
the final decision analysis. While the process participants were completing each stage of
the process, they also gained experience with the component and were allowed time to
develop a good understanding of the component and its intricacies.

The benchmarking exercise started the project. Four veteran American Marine employees
with over 85 years of combined marine experience developed a list of clutches
in order to clarify the roles of the z-drive components from a safety view point. This
exercise was used to pool information on the available clutch types and their applications.
Participants in the following processes were introduced to the benchmarking material
prior to each exercise.




                                                                              Page 5 of 32
An energy trace and barriers diagram was completed in order to graphically represent the
drive line and draw focus to the components and systems that have the ability to impart
energy into a human.

A PHL was developed for the clutch by a cross functional team. This list contains each
basic failure of a generic clutch. This list was made prior to clutch hazard analysis in
order to simply list basic failures and gain clarity of the ways any clutch can fail.

A PHA was then completed, by a cross functional team, in order to gain a better
understanding of clutch failure modes and their effects. The process used for this analysis
was failure modes and effects analysis.

After the benchmarking and safety based processes were completed for input data, a
decision analysis was carried out using a VA / VE process. This process used a cross
functional team from marketing, service engineering, manufacturing, and quality in a
weighted criteria ranking process. During this process, the team realized the clutch type
decision is closely related to the driveline configuration. In order properly rank the clutch
type, the driveline configuration was also brainstormed and analyzed along with the
clutch type. The cross functional team then decided on a clutch type and driveline
configuration for the new z-drive. This decision used the information gathered and
analyzed in the five preceding processes. The VA / VE process was used to organize the
data collected in the above procedures along with data from marketing research,
manufacturing, and quality in order to guide a decision on the clutch type to be used in
the new z-drive.


ALTERNATIVES CONSIDERED

The benchmarking exercise delivered 5 basic clutch types used internally, by the marine
industry, or in the automotive and off-highway industries. Hazard analysis was conducted
on these five clutch types in order to provide input in the decision analysis. The decision
analysis utilized brainstorming to list 12 clutch types. These twelve types were condensed
to seven overall clutch and drive line system configurations in a group exercise. Then, the
top five clutch types and drive line configurations were ranked according to weighted
criteria. The top four clutch type and driveline configurations were:

       1.   Cone Clutch (Bravo Style) in the upper portion of the z-drive
       2.   Dog Clutch (Alpha Style) in the lower portion of the z-drive
       3.   Synchronized Toothed / Dog (w/ 2 Stage Engine Coupler)
       4.   Wet Disk Master Clutch (One Engine) / Dog Selector (In Drive)




                                                                                Page 6 of 32
ANALYSIS AND RESULTS

Benchmarking

The clutch type benchmarking document can be viewed in appendix A. Brainstorming
was used in a small group of experts for this activity. Six clutch types were listed. Their
usage was broken into the following three categories.

                       Internal (Mercury Marine)
                       Industry (Recreational / Light Commercial Marine)
                       Functional (Automotive / Off Highway)

Their product name, application in the system, and means of actuation were listed. This
list was generated to provide information to the cross-functional team members in the
PHA and VA / VE processes. This list was composed of six major clutch types used in
similar applications. It provided a great starting point for team conversation and helped
the team members to get familiar with the clutch component prior to starting their own
group activities. Ultimately, this list contained the clutch type selected by the team.

Energy Trace and Barriers Diagram (ETBD)

The deliverable of this process can be found in appendix B. This process was conducted
by Phillip Magee and was also designed to be used as information in the following PHA
and VA / VE group processes. This process basically uses a diagram to represent the
current Charlie and Delta z-drive configurations. A table below the diagram lists the type
of energy present in each component or subsystem and any barriers to this energy. This
process is based on the theory that any injury to humans must be caused by energy being
imparted into them. For this reason, it is critical to trace the energy in the system and be
aware of any place that this energy is not barred from human contact. This process has
shown that the propeller is the only part of the driveline that has energy available to
human contact. The propeller is used to impart energy into the water to propel the boat.
This is similar to a tire on an automobile imparting energy to the ground to propel the
automobile. This diagram also shows that the propeller energy is controlled by the clutch.
The decoupling of the clutch is the action that does not allow the propeller to contain
rotational energy and is of high importance when designing a driveline. The ETBD was
used to document the energy and barriers in the z-drive and focus attention on the areas
critical for imparting energy. The propeller was targeted as the component that imparts
energy. Within the project guidelines, the z-drive and propeller configuration are given
and must be maintained. This drives the focus of the energy to the clutch which acts as a
switch to either transmit power or decouple it from the propeller. This document was
presented to participants in the PHA and VA / VE as support information. The ETBD
was successful in targeting the clutch as an important component and relaying its
function as an energy barrier to the cross-functional team.




                                                                                Page 7 of 32
Preliminary Hazard List (PHL)

The preliminary hazard list is can be found in appendix C. This list was done prior to the
PHA and decision analysis in order to simply list the hazards associated with clutches of
any type. This list was instrumental in presenting each type of hazard of the clutch. It was
quite evident to the team that the clutch failure to forward or to reverse would mean that
the driveline would be supplying rotating energy to the propeller when the operator
thought the propeller was static. These two hazards were clearly seen as the least
desirable for the design. It was also clearly seen that the clutch failure to neutral was less
critical from a safety viewpoint. This list also allowed the team to discuss the mobility
failures of the clutch when it fails to neutral. At this point the team understood the
hazards of the clutch in a z-drive. Now, a FMEA was needed to better analyze the details
of the clutch hazards.

Preliminary Hazard Analysis (PHA – FMEA)

The generic clutch portion of the PHA can be found in appendix D. PHAs of each clutch
type were also completed, but have not been listed in the appendix. They are very similar
to the PHA for the generic clutch. Differences of each clutch type as compared to the
generic clutch PHA are listed in appendix D. The FMEA process was used to perform a
PHA on a generic clutch and five clutch types (Dog, Cone, Wet Disk, Dry Disk, and
Band). This was a team process. The team was shown the benchmarking study and the
ETBD prior to the FMEA process. In this process, each failure was analyzed by listing
each failure mode along with its cause, effect, and design validation process. Severity,
occurrence, and detection rates were scored and an overall risk priority number was
developed for each failure mode. During this process, it was evident that the dog clutch is
superior to the other clutches because it does not have the ability to fail in a way that
would cause it to transmit torque when it should not transmit torque. This process also
ranked that failure with the highest possible severity number of 10 and a high overall risk
priority number of 120. This data was used in the following decision analysis.

Decision Analysis (VA / VE)

The VA / VE can be viewed in appendix E. The Benchmarking data, ETBD, PHL, and
PHA were used as supporting documentation in the VA / VE. In the VA / VE, the clutch
functions were listed and analyzed. Then a list of twelve clutch types was brainstormed to
insure that all types were considered. At this point, it was evident to the group that the
way a clutch is used in the system is important to its function and the way it would be
ranked. The group then brainstormed a total of seven clutch type and drive-line
configurations.




                                                                                 Page 8 of 32
Idea # Description
      1      Cone Clutch (Bravo Style)
      2      Dog Clutch (Alpha Style)
      3      Synchronized Toothed / Dog (w 2 Stage Engine Coupler)
      4      Wet Disk Master Clutch (On Eng.) / Dog Gear Selector ( In Drive)
      5      Wet Disk Synchronized Dog Master Clutch (On Eng.) / Dog Gear Selector (In Drive)
      6      Dry Disk Master Clutch (On Eng.) / Cone Clutch Gear Selector (In Drive)
      7      Torque Converter (On Eng.) / Cone Clutch Gear Selector (In Drive)


The top four clutch and drive-line configurations were T charted by the team in order to
list pros and cons for each. Each con was discussed to attempt a solution. At this point the
team was familiar with each configuration and was ready for developing weighted criteria
and ranking. Eight criteria were developed for the configuration and given a weight using
a paired comparison matrix. Then the “must” and “want” criteria were separated to draw
a line between criteria that are necessary and criteria that are desirable.

Eval. Criteria                                                           Rating %
Safety (Must)                                                                    25.0
Reliability (Must)                                                               21.4
Durability Envir./Time/Cycles (Must)                                             17.9
NVH (Want)                                                                       14.3
Packaging (Want)                                                                 10.7
Serviceability / Maintenance (Want)                                               7.1
MFG. Mach. / Assy. (Want)                                                         3.6
Styling (Want)                                                                    0.0
                                                                                 100

Each configuration was ranked in its ability to meet the criteria on a scale of 1 to 10.
These rankings were weighted and added for each criteria to develop an overall score.
That score was then divided by the cost of the clutch and necessary mating components
in the driveline to develop a valued based score. Safety, reliability, and durability were
determined to be “musts” and are highly weighted. This affected the overall score of the
clutch types. The dog clutch ranked the highest based on the weighted criteria and the
value. The wet disk master clutch on the engine and dog gear selector in the drive idea
ranked second based on the criteria but last from a value perspective due to its higher
cost. The cone clutch ranked third from criteria and a distant second in value. The
synchronized toothed / dog clutch ranked last based on the criteria and third in value.
Clearly, the dog clutch was found to be the best overall clutch for satisfying customer
needs and it greatly exceeded the other clutch types from a value perspective.




                                                                                       Page 9 of 32
    VA / VE Results                                    Idea 1         Idea 2     Idea 3     Idea 4
    Total Weighted Criteria Rank                           671.4         789.3      589.3       725.0
    Estimated Cost                                       $100.00        $50.00    $120.00    $170.00
    Value Ratio      Criteria/Cost                              6.7       15.8        4.9            4.3



The cross functional team discussed the results of all five of the above processes and their
feelings about the validity of the results. The team agreed that the results were valid. The
dog clutch has always been found to be safe, reliable, durable, and very cost effective.
Several attempts have been made in the past to replace it, but they have all failed at
providing a better yet cost effective clutch alternative.

CONCLUSIONS AND RECOMMENDATIONS

The team used the information developed in this project along with marketing input to
develop a z-drive strategy that would utilize the positive attributes and low cost of a dog
clutch for cost sensitive customers while allowing for design flexibility and satisfying the
needs and wants of more discriminating customers willing to pay more for a more refined
product.

The team proposes a base product utilizing a dog clutch in the upper end of the z-drive.
This upper drive can be fitted with several different lower gearcases to satisfy different
boat applications. Refinements in the drive-line compliance have the opportunity to
slightly improve the noise, vibration, and harshness characteristics of this base model.
This same z-drive will be fitted with a wet disk master clutch on the engine for
decoupling drive torque during shifting in a premium version of this product. This
product retains all of the safety, reliability, and durability attributes of the dog clutch
while providing greatly improved noise, vibration, and harshness characteristics during
shifting. This design strategy molds ideas 2 and 4 of the VA / VE into one modular
approach. This design selection maintains cost competitiveness in the base product while
providing superior aesthetics in the premium product at a higher cost.




                                                                                    Page 10 of 32
It is recommended that system models be created and for the modular z-drive. These
models should then be analyzed for shift characteristics. It is also recommended that a
prototype modular z-drive be built and tested in the dog clutch only configuration and in
the wet disk master clutch and dog gear selector styles. Cost information has been based
on manufacturing engineering, and product engineering estimations to this point. A more
detailed cost study of the shift system is recommended in conjunction with the more
detailed design models and prototype. This will improve the accuracy of the value studies
conducted. This activity can be completed with the current new drive engineering team
and budget before December 17, 2004.




                                                                           Page 11 of 32
Appendix A             Benchmark Study
Mercury Marine Clutch Type Benchmark
Dog Clutch                            Participants: Phillip Magee, Tom Yerby
3/03/04 – 4/07/04                                      Ken Grainger, Robert Grantham
The objective of this benchmarking exercise is to form a list of clutches that are available
for use and are readily adaptable to the sterndrive system. This benchmarking aids in
providing a list of clutch types, their applications, and means of actuation.

Dog Clutch
       Internal (Mercury Marine)
              Product                                 Application            Actuation
              Alpha Sterndrive                        Primary Clutch         Mechanical
              MC II Drive                             Primary Clutch         Mechanical
              215 E Drive                             Gear Selector          Electric
              0-Drive                                 Primary Clutch         Mechanical
              All Outboards                           Primary Clutch         Mechanical
       Industry (Recreational / Light Commercial Marine)
             Product                           Application                   Actuation
             OMC Drive                         Primary Clutch                Mechanical
             All Outboards                     Primary Clutch                Mechanical
             Konrad Drive                      Primary Clutch                Mechanical
             GLM Drive                         Primary Clutch                Mechanical
       Functional (Automotive / Off Highway)

               Product                                Application            Actuation
               Agricultural                           Various – low speed    Mechanical
               Oil Well Pulling Unit Safety Brake     Secondary Brake        Mechanical
               Auto. Performance Transmissions        Gear Selector          Mech. / Elec.

Cone Clutch
       Internal (Mercury Marine)
              Product                                 Application            Actuation
              Bravo Sterndrive                        Primary Clutch         Mechanical
       Industry (Recreational / Light Commercial Marine)
             Product                           Application                   Actuation
             Volvo Sterndrives                 Primary Clutch                Mechanical
             Yamaha Sterndrives                Primary Clutch                Mechanical
             OMC Cobra                         Primary Clutch                Mechanica
       Functional (Automotive / Off Highway)
             None



                                                                              Page 12 of 32
Wet Disk
       Internal (Mercury Marine)
              Product                          Application      Actuation
              TR Sterndrive                    Primary Clutch   Hydraulic
              Inboard Trans.                   Primary Clutch   Hydraulic
              Six Drive Trans.                 Primary Clutch   Hydraulic

       Industry (Recreational / Light Commercial Marine)
             Product                           Application      Actuation
             Yamaha Sterndrive                 Primary Clutch   Hydraulic
             BMW Sterndrive                    Primary Clutch   Mechanical
             All Inboard Trans.                Primary Clutch   Hydraulic

       Functional (Automotive / Off Highway)
             Product                           Application      Actuation
             Automated Planetary               Primary Clutch   Hydraulic
             Lay Shaft Transmissions.          Primary Clutch   Hydraulic

Dry Disk
       Internal (Mercury Marine)
              Product                          Application      Actuation
              215 E Sterndrive                 Primary Clutch   Electric

       Industry (Recreational / Light Commercial Marine)

             None

       Functional (Automotive / Off Highway)
             Product                           Application      Actuation
             Manual                            Primary Clutch   Mech. / Hyd.
             Automated Manual Transmissions    Primary Clutch   Hydraulic

Band
       Internal (Mercury Marine)
              Product                          Application      Actuation
              TR Sterndrive                    Reverse Clutch   Hydraulic

       Industry (Recreational / Light Commercial Marine)
             Product                           Application      Actuation
             Chris Craft Inboard Trans.        Reverse Clutch   Hydraulic

       Functional (Automotive / Off Highway)
             Product                           Application      Actuation
             Automated Planetary               Primary Clutch   Hydraulic
             Constant Velocity Transmissions   Primary Clutch   Hydraulic



                                                                 Page 13 of 32
Centrifugal Clutch
     Internal (Mercury Marine)
            Product                          Application      Actuation
            None

     Industry (Recreational / Light Commercial Marine)
           Product                           Application      Actuation
           None

     Functional (Automotive / Off Highway)
           Product                           Application      Actuation
           Go Cart / Snowmobile              Primary Clutch   Mechanical




                                                               Page 14 of 32
Appendix B                Energy Trace and Barriers Diagram




                                   Charlie                                              Delta

Item #   Desc.                    Energy                                            Barrier
   1     Accessory Drive System   Mechanical -Rotational   When Engine is Running   Hatch
   2     Flywheel                 Mechanical -Rotational   When Engine is Running   Hatch - Flywheel Housing
   3     Universal Joint          Mechanical -Rotational   When Engine is Running   Hatch - Bellows
   4     Upper Gearset            Mechanical -Rotational   When Engine is Running   Drive Shaft Housing
   5     Clutch                   Mechanical -Rotational   When Activated F/R       Drive Shaft Housing
   6     Vertical Drive Sahfts    Mechanical -Rotational   When Activated F/R       Drive Shaft Housing - Gearcase
   7     Lower Gearset            Mechanical -Rotational   When Activated F/R       Gearcase
   8     Propeller Shaft          Mechanical -Rotational   When Activated F/R       Gearcase - Propeller
   9     Propeller                Mechanical -Rotational   When Activated F/R       None




                                                                                          Page 15 of 32
Appendix C       Preliminary Hazard List



Preliminary Hazard List - Clutch Activation

 Item #     Failure
    1       Clutch Failure
          a          To Forward
          b          To Neutral
          c          To Reverse




                                              Page 16 of 32
Appendix D                         Preliminary Hazard Analysis

                                                                Performed
                                                                Before/After
                                                                Design Made? (underline
                                                                one)                          POTENTIAL FAILURE MODE AND EFFECTS ANALYSIS (System)

       TITLE: Generic Clutch                                                                  FMEA DATE:            03/18/2004
      MODEL: Sterndrive                                                                       TEAM LEADER:          Tom Yerby
  CORE TEAM: Phillip Magee, Dennsi Gunderson, Paul Govek, Woody Smith, Ken Grainger, Rich     FACILITATOR:          Paul Govek
              Todhunter, Manish Kulkarni, Kieth Schmidt, John Behara
    PROJECT: New Sterndrive                                                                   Full Attendance?      Y N (underline one)
ITEM/            POTENTIAL             POTENTIAL            S     POTENTIAL CAUSE(S) O              CURRENT         D R RECOMMENDED
FUNCTION           FAILURE              EFFECT(S)           E       MECHANISM(S) OF C                 DESIGN         E P    ACTION(S)
                     MODE              OF FAILURE           V          FAILURE          C          VALIDATION        T N
CLUTCH
TRANSMIT       INADEQUATE OR      NO BOAT MOVEMENT         8    CLUTCH DESIGN          2      -HISTORY              2   32   NA
TORQUE/        DECREASING ABILITY                               SPECIFICATION - TORQUE        -BOATING & NON-
ROTATION       TO TRANSMIT                                      CAPACITY REQUIREMENT          BOATING INDUSTRY
               TORQUE/ ROTATION                                                               STDS
                                                                                              -MODELING
                                                                                              -DESIGN ANALYSIS
                                                                                              -COMPONENT TESTING
                                                                                              -SYSTEM LEVEL TESTING

                                   ENGINE OVERREV          7
                                   EXCESS HEAT IN CLUTCH   6
                                   SYSTEM

NOT TRANSMIT   TRANSMITS TORQUE/ CONTINUOUS BOAT           10   CLUTCH DESIGN             4   -HISTORY              3   120 EVALUATE
TORQUE/        ROTATION          MOVEMENT                       SPECIFICATION                 -BOATING & NON-               CONCEPTS
ROTATION                                                                                      BOATING INDUSTRY
                                                                                              STDS
                                                                                              -MODELING
                                                                                              -DESIGN ANALYSIS
                                                                                              -COMPONENT TESTING
                                                                                              -SYSTEM LEVEL TESTING

                                   ENGINE NO START         8

RECEIVE/       DOES NOT RECEIVE/   CONTINUOUS BOAT         10   CONNECTION,               4   -HISTORY              3   120 EVALUATE
TOLERATE       TOLERATE SIGNAL     MOVEMENT                     ACTUATION, & CLUTCH           -BOATING & NON-               CONCEPTS
SIGNAL LOAD    LOAD                                             DESIGN SPECIFICATIONS         BOATING INDUSTRY
                                                                                              STDS
                                                                                              -MODELING
                                                                                              -DESIGN ANALYSIS
                                                                                              -COMPONENT TESTING
                                                                                              -SYSTEM LEVEL TESTING

                                   NO SHIFT                9
                                   ENGINE NO START         8
                                   ENGINE OVERREV          7

TOLERATE       DOES NOT TOLERATE CONTINUOUS BOAT           10   ACTUATION & CLUTCH        4   -HISTORY              3   120 EVALUATE
ACTUATION      ACTUATION THRUST MOVEMENT                        DESIGN SPECIFICATIONS         -BOATING & NON-               CONCEPTS
THRUST FORCE   FORCE                                                                          BOATING INDUSTRY
                                                                                              STDS
                                                                                              -MODELING
                                                                                              -DESIGN ANALYSIS
                                                                                              -COMPONENT TESTING
                                                                                              -SYSTEM LEVEL TESTING

                                   NO SHIFT                9
                                   ENGINE NO START         8
                                   ENGINE OVERREV          7




                                                                                                                         Page 17 of 32
                                                               Performed
                                                               Before/After
                                                               Design Made? (underline
                                                               one)                          POTENTIAL FAILURE MODE AND EFFECTS ANALYSIS (System)

       TITLE: Generic Clutch                                                                 FMEA DATE:            03/18/2004
      MODEL: Sterndrive                                                                      TEAM LEADER:          Tom Yerby
  CORE TEAM: Phillip Magee, Dennsi Gunderson, Paul Govek, Woody Smith, Ken Grainger, Rich    FACILITATOR:          Paul Govek
              Todhunter, Manish Kulkarni, Kieth Schmidt, John Behara
    PROJECT: New Sterndrive                                                                  Full Attendance?      Y N (underline one)
ITEM/            POTENTIAL             POTENTIAL            S     POTENTIAL CAUSE(S) O             CURRENT         D R RECOMMENDED
FUNCTION           FAILURE              EFFECT(S)           E       MECHANISM(S) OF C                DESIGN         E P    ACTION(S)
                     MODE              OF FAILURE           V          FAILURE          C         VALIDATION        T N
CLUTCH
TOLERATE       DOES NOT TOLERATE NO BOAT MOVEMENT        8     CLUTCH DESIGN             2   -HISTORY              2   32   NA
TORSIONAL      TORSIONAL SHOCK &                               SPECIFICATION - NVH &         -BOATING & NON-
SHOCK &        VIBRATION                                       TORSIONAL SHOCK               BOATING INDUSTRY
VIBRATION                                                      CAPACITY & LIFE               STDS
                                                               REQUIREMENT                   -MODELING
                                                                                             -DESIGN ANALYSIS
                                                                                             -COMPONENT TESTING
                                                                                             -SYSTEM LEVEL TESTING

                                 ENGINE OVERREV          7
                                 EXCESS HEAT IN CLUTCH   6
                                 SYSTEM

ABSORB/        INADEQUATELY      EXCESS NOISE &          4     CLUTCH DESIGN         2       -HISTORY              2   16   NA
DAMPEN         ABSORB/ DAMPEN    VIBRATION                     SPECIFICATION - NVH &         -BOATING & NON-
TORSIONAL      TORSIONAL SHOCK                                 TORSIONAL SHOCK               BOATING INDUSTRY
SHOCK LOAD     LOAD                                            CAPACITY REQUIREMENT          STDS
                                                                                             -MODELING
                                                                                             -DESIGN ANALYSIS
                                                                                             -COMPONENT TESTING
                                                                                             -SYSTEM LEVEL TESTING



DISSIPATE HEAT INADEQUATELY      CONTINUOUS BOAT         10    CLUTCH DESIGN             4   -HISTORY              3   120 EVALUATE
               DISSIPATES HEAT   MOVEMENT                      SPECIFICATIONS                -BOATING & NON-               CONCEPTS
                                                                                             BOATING INDUSTRY
                                                                                             STDS
                                                                                             -MODELING
                                                                                             -DESIGN ANALYSIS
                                                                                             -COMPONENT TESTING
                                                                                             -SYSTEM LEVEL TESTING

                                 NO SHIFT                9
                                 ENGINE NO START         8
                                 ENGINE OVERREV          7




                                                                                                                        Page 18 of 32
FMEA – Dog, Cone, Wet Disk, Dry Disk, Band Clutch



    Dog            Same as generic clutch except (“Not
                   Transmit Torque / Rotation” failure
                   mode is scored as low potential)

    Cone           Same as generic clutch

    Wet Disk       Same as generic clutch

    Dry Disk       Same as generic clutch

    Band           Same as generic clutch




                                                  Page 19 of 32
Appendix E           Decision Analysis
New Drive Shift System VA / VE                                                            1
       4/7/2004
Value Analysis / Value Engineering

Process:
     Project Definition                 Go Over Product Plan
     Function Worksheet                 Verb - Noun Function List
     Function Analysis                  Organize Function List
     Brainstorming Designs              Let Creativity Flow (not Flood)
     Brainstorming Designs              Sort Out Top 3 or 4 Designs
     T - Chart                          Pro's and Con's of Top 3 or 4
     Paired Comparison Matrix           Pick Rating Criteria
     Idea Selection Worksheet           Score Top 3 or 4 Designs.

Attendance:
      Invited             Dept.         Participants
      Tom Yerby           Eng.
      Dennis Gunderson    Eng.          Dennis Gunderson
      PhillIp Magee       Eng.          Phillip Magee
      Lawrence Robinson   Eng.          Mark McCartor
      Rod Caldwell        Eng.          Rod Caldwell
      Manish Kulkarni     Eng.          Manish Kulkarni
      Keith Schmidt       Eng.          Keith Schmidt
      Darrin Doty         Eng.
      Bob Burrell         Eng.          Bob Burrell
      John Behara         Eng.          John Behara
      Chad Martin         Integration
      Rich Todhunter      Integration
      Craig Armstrong     Mfg. Eng.
      Woody Smith         Mfg. Eng.     Randy Stokes
      Larry Miller        Quality
      Ken Grainger        Service
      Paul Govek          Eng.
      Robert Grantham     Marketing     Robert Grantham




                                                                          Page 20 of 32
                  Rules                                                                                     2
Decisions
  Type
      Command - Quick , Based on Judgment and Intelligence of Decision Maker

     Consensus     - Teamwork, Requires Cooperation, Based on Judgment and Intelligence of the Team

  We plan to consider all input during this VA / VE session but will quickly move through decisions based
  on MAJORITY RULES consensus decisions.

Brainstorming

  No ideas are evaluated during the brainstorming session. No criticism.
  Say It - Write It - Toss It
  Get Creative




                                                                                  Page 21 of 32
PROJECT:                                                                                             3
           New sterndrive


PROJECT TYPE:
           Design


OBJECTIVES:
           Select shift system type or types and configuration




SCOPE:
           New sterndrive or drives will replace current Alpha and Bravo sterndrives
           Design primarily between engine and propeller
           New design may effect engine controls (electronics)
           New design may effect shift actuation system (control handle and linkages)


SCOPE DOES NOT INCLUDE:
           Engine
           Propellers
COST:
           Targets not officially set
           Known:
                  Alpha replacement product is cost sensitive
                 Bravo replacement product is less cost sensitive and more aesthetically sensitive




                                                                            Page 22 of 32
Function Worksheet                                                                        4
          Verb                      Noun    Type               Specifications / Comment

  Transmit                Torque              B
  Transmit               Rotation             B
  Decouple                Torque              B
  Decouple               Rotation             B
  Receive                  Signal             B
  Tolerate                 Signal             R
  Dissipate                 Heat              R
   Absorb             Torsional Shock         R              vibration / impact
  Engage               Mating Face            B
  Tolerate             Engagement             R




Types of Functions   B - Basic             R - Required Secondary
                     HO - Higher Order     A - Asthetic Secondary
                                           U - Unwanted Secondary




                                                                     Page 23 of 32
Function Analysis System Technique Diagram                                             5
                           Verb     Noun            Verb      Noun
How                                                                    Why


H.O Func.                                                              Assumed Func.
Basic Function
Transmit Rotation Engage            Mating Face     Receive   Signal Transmit Torque
Decouple Rotation                                                    Decouple Torque
Req'd Secondary Function
                           Tolerate Engagement       Tolerate Signal
                           Dissipate Heat
                           Absorb    Torsional Shock




                                                                 Page 24 of 32
New Sterndrive                                                               6
Brainstorming


Idea # Description
   1 Cone Clutch
   2 Dog Clutch
   3 Synchronized Toothed / Dog
   4 Wet Disk Clutch
   5 Dry Disk Clutch
   6 Magnetic Clutch
   7 Band Clutch
   8 Belt (w Slip for Neutral)
   9 Centrifugal
  10 Sprag
  11 Spring Clutch
  12 Lock -Up Torque Converter with Disk Brake for Neutral




                                                             Page 25 of 32
New Sterndrive                                                                                 7
Brainstorming

Idea # Description
     1      Cone Clutch (Bravo Style)
     2      Dog Clutch (Alpha Style)
     3      Synchronized Toothed / Dog (w 2 Stage Engine Coupler)
     4      Wet Disk Master Clutch (On Eng.) / Dog Gear Selector ( In Drive)
     5      Wet Disk Synchronized Dog Master Clutch (On Eng.) / Dog Gear Selector (In Drive)
     6      Dry Disk Master Clutch (On Eng.) / Cone Clutch Gear Selector (In Drive)
     7      Torque Converter (On Eng.) / Cone Clutch Gear Selector (In Drive)




                                                                        Page 26 of 32
VAVE: New Sterndrive                                                          8

Cone Clutch (Bravo Style)
              +                           -                What Can Be Done
Proven technology           High actuation force           Self actuate
Compact                     Sensitive to actuation force
High capacity               Sensitive to tolerances
Limp Home                   Difficult to measure
Moderate cost               Sensitive to finish            Monitor finish
Durable                     Moderate NVH
Moderate NVH                Fails in closed position
                            Temperature sensitive
                            Sensitive to contamination




                                                             Page 27 of 32
VAVE: New Sterndrive                                                           9

Dog Clutch (Alpha Style)
                   +                     -              What Can Be Done
Durable                      Loud                       2 stage eng. coupler
Robust                       Harsh                      2 stage eng. coupler
Compact                      Abrupt                     2 stage eng. coupler
Clutch and selector          Actuation time sensitive
                                                        Use with newer tech.
                                                        sychronizeres,
Low cost                     Old technology             couplings, clutches
Simplistic                   No limp home
Proven technology
Ratchetablity
Fails open
Tolerable to contamination




                                                             Page 28 of 32
VAVE: New Sterndrive                                                           10

Synchronized Toothed / Dog (w 2 Stage Engine Coupler)
             +                           -              What Can Be Done
Simple                      No ratchetability
                            Not proven in
Proven technology           marine Appl.
Automotive
application                 Complex assy.

                    More components
Moderately compact than dog / cone
NVH better than dog
/ cone              Temp. sensitive
                    No limp home
                    Less reliable than
                    dog




                                                                   Page 29 of 32
VAVE: New Sterndrive                                                                  11

Wet Disk Master Clutch (On Eng.) / Dog Gear Selector ( In Drive)
                +                               -              What Can Be Done
                                  Increased
Perfect NVH                       complexity
Temperature tolerant              Increased cost
Limp home                         Lower reliability
                                  No water pump in
Dog fails open                    drive
                                  Requires hydraulic
                                  pump




                                                                      Page 30 of 32
                                                                                                      Page 31 of 32
New Sterndrive                                                                                   12
Eval. Criteria                         Decision                                   Total Rating %
Reliability (Must)                     A          A   A   A   E   A   A   A         6     21.4
Durability Envir./Time/Cycles (Must)              B   B   B   E   B   B   B         5     17.9
Serviceability / Maintenance (Want)                   C   C   E   F   G   C         2     7.1
MFG. Mach. / Assy. (Want)                                 D   E   F   G   D         1     3.6
Safety (Must)                                                 E   E   E   E         7     25.0
Packaging (Want)                                                  F   G   F         3     10.7
NVH (Want)                                                            G   G         4     14.3
Styling (Want)                                                            H         0     0.0
                                                                              I     0     0.0
                                                                                   28     100
                                                                                                   13
#   Evaluation Criteria                     Weight     Idea 1    Idea 2      Idea 3       Idea 4
1 Reliability (Must)                           21.43         6        9            4           5
                                                         128.6    192.9         85.7       107.1
2 Durability Envir./Time/Cycles (Must)         17.86         7        9            6           9
                                                         125.0    160.7        107.1       160.7
3 Serviceability / Maintenance (Want)           7.14         9        9            8           6
                                                          64.3     64.3         57.1        42.9
4 MFG. Mach. / Assy. (Want)                     3.57         6        9            4           5
                                                          21.4     32.1         14.3        17.9
5 Safety (Must)                                25.00         6        8            6           8
                                                          150      200          150         200
6 Packaging (Want)                             10.71         9        9            7           5
                                                          96.4     96.4         75.0        53.6
7 NVH (Want)                                   14.29         6        3            7          10
                                                          85.7     42.9        100.0       142.9
8 Styling (Want)                                0.00         0        0            0           0
                                                             0        0            0           0
9                                       0       0.00
                                                             0        0       0       0
    Total Weighted Criteria                      100     671.4    789.3   589.3   725.0
    Estimated Cost                                     $100.00   $50.00 $120.00 $170.00
    Value Ratio    Criteria/Cost                           6.7     15.8     4.9     4.3




                                                                          Page 32 of 32

				
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