SynchroLite ~ Power Train - Reduction - Secondary (for 2 engines)

Overview:

Planetary gearing with straight teeth. The sun gear is driven from the primary reduction. The mast is driven from the planet holder. The ring gear is held stationary by the soft-start clutch during flight and is free to rotate when power to the rotors is not desired.

WAS CHOICE 12 DP ~ Sun = 24 / Planets = 18 / Ring = 60 teeth.

Now considering using 4 planetary gears and 16 DP to reduce weight ~ September 30, 2001. See NEW IDEA

Pros & Cons of Using Planetary Gearing:

Advantages:
  1. Greater efficiency; resulting in more of the engine's power getting to the rotor.
  2. More teeth in contact; resulting in a smaller lighter reducer.
  3. Lower friction and therefore lower requirement for cooling.
  4. The housing is subjected to mainly only torsional loads; resulting in a lighter unit.

Disadvantages:
  1. Higher initial cost.

Picture:

Eventually

FORM: Power Train - Reduction - Secondary

16 DP ~ 31/23/77 teeth: NEW IDEA 4 planetary gears only. For slightly smaller mast OD. Ratio is 3.4839:1

The ring gear's diameter will be about 1/4" smaller and the wall of the sun can have a little more meat. Face width about 0.75", to give a strength hp of 25 to 30 divided by 4 gears.

12 DP ~ 24/18/60 teeth: WAS CHOICE Can have 3 or 4 planetary gears. For smaller mast OD.

12 DP ~ 25/19/63 teeth: OBSOLETE Can have 4 planetary gears; but not 3. Will work with larger mast OD than 24/18/63. Has 0.7% higher ratio.

 

 Working Papers:

 

DESIGN:

B011

MAKE:

B063

 

Items:

DESIGN:

 

Name

Item

 

Power Train - Reduction - Secondary - Teeth Layout 31/23/77 teeth ~ NEW IDEA

0985

 

Power Train - Reduction - Secondary - Teeth Layout 24/18/60 teeth ~ WAS CHOICE

0772

 

Power Train - Reduction - Secondary - Teeth Layout 25/19/63 teeth ~ OBSOLETE

0134

MAKE:

 

Name

Item

 

16 DP - 31/23/77 teeth: ~ NEW IDEA

 

 

Power Train - Reduction - Secondary - Assembly- 16 DP

0981

 

Power Train - Reduction - Secondary - Gear - Planet - 16 DP - 23 tooth

0977

 

Power Train - Reduction - Secondary - Gear - Sun - 16 DP - 31 tooth

0979

 

Power Train - Reduction - Secondary - Gear - Ring - 16 DP - 77 tooth

0980

 

Power Train - Reduction - Secondary - Housing - Shallow- 16 DP

0983

 

Power Train - Reduction - Secondary - Housing - Deep- 16 DP

0984

 

Power Train - Reduction - Secondary - Planet Carrier - 16 DP

0982

 

12 DP - 24/18/60 teeth: ~ WAS CHOICE

 

 

Power Train - Reduction - Secondary - Assembly- 12 DP

0198

 

Power Train - Reduction - Secondary - Gear - Planet - 12 DP - 18 tooth

0771

 

Power Train - Reduction - Secondary - Gear - Sun - 12 DP - 24 tooth

0774

 

Power Train - Reduction - Secondary - Gear - Ring - 12 DP - 60 tooth

0773

 

Power Train - Reduction - Secondary - Housing - Shallow - 12 DP

0309

 

Power Train - Reduction - Secondary - Housing - Deep - 12 DP

0307

 

Power Train - Reduction - Secondary - Planet Carrier - 12 DP

0247

 

Power Train - Reduction - Secondary - Inner Ring

0647

 

 

 

 

12 DP - 25/19/63 teeth: ~ OBSOLETE

 

 

Power Train - Reduction - Secondary - Gear - Planet - 12 DP - 19 tooth

0755

 

Power Train - Reduction - Secondary - Gear - Sun - 12 DP - 25 tooth

0627

 

Power Train - Reduction - Secondary - Gear - Ring - 12 DP - 63 tooth

0762

BUY:

 

Name

Item

 

PT - Clutch - Overrunning - Ramp / Roller - Warner-Stieber - ASK-60

0567

 

PT - Clutch - Overrunning - Sprag - Warner-Stieber - GFK-35 ~ for NEW IDEA

0978

Potential Problems: 

There is the desire to reduce weight. Modify the secondary reduction units so that the Strength Service Factor is 1.0 and the Durability Service Factor is 0.667. This is the same as the Ultrasport 254; and it makes sense. In fact, because of duplicity of power trains the factors could be slightly lower. Also use four planet gears and helical gears.

Keep the synchro gear factors high.

See NEW IDEA, as a new possible alternative to WAS CHOICE.

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Last Revised: October 12, 2001