Clutch schedule for a sixspeed Lepelletier transmission
Transmissions
The 6Speed Lepelletier consists of one planetary gear set, one Ravigneaux gear set, and five disk friction clutches. The transmission base shaft connects to the ring gear of the planetary gear set. The follower shaft connects to the ring gear of the Ravigneaux gear set. Three of the clutches control the power flow paths between the planetary and Ravigneaux gear sets. The other two clutches serve as brakes, grounding various gears of the Ravigneaux set to the transmission housing.
This diagram shows a sixspeed Lepelletier transmission. The labels for the gear components are superimposed on the input and output gears. The table lists the gear and clutch components that are labeled in the diagram.
Label  Component 

P.G.  Planetary gear 
R.G.  Ravigneaux gear 
R  Ring gear 
C  Planet gear carrier 
S  Sun gear 
SL  Large sun gear 
SS  Small sun gear 
A–C  Forward clutches that control the power flow path 
D–E  Forward, braking clutches 
The drive ratio between the transmission input and output shafts follows from the elementary gear ratios specified for the gear blocks. The elementary gear ratios are
$${g}_{1}=\frac{{N}_{PR}}{{N}_{PS}},$$
$${g}_{2}=\frac{{N}_{PR}}{{N}_{RSL}},$$
$${g}_{3}=\frac{{N}_{RR}}{{N}_{RSS}},$$
N_{PR} is the number of teeth in the planetary ring gear.
N_{PS} is the number of teeth in the planetary sun gear.
N_{RR} is the number of teeth in the Ravigneaux ring gear.
N_{RSL} is the number of teeth in the Ravigneaux large sun gear.
N_{RRS} is the number of teeth in the Ravigneaux small sun gear.
The table shows the clutch schedule, driveratio expressions, driveratio default values, and the plowerflow diagrams for each gear of the 6Speed Lepelletier block.
The letters in the clutch schedule columns denote the brakes
and clutches. A value of 1
denotes a locked state
and a value of 0
an unlocked state. The clutch
schedule generates these signals based on the Gear port input signal.
The signals are scaled through a Gain block
and used as actuation inputs in the clutch blocks.
The plowerflow diagrams show the power flow paths between input and output shafts for each gear setting. Power flow is shown in orange. Connections to the transmission housing (a mechanical ground) are shown in black.
Gear  Clutch Schedule  Drive Ratio Equation  Default Ratio  Power Flow  

A  B  C  D  E  
6  0  1  0  0  1  $$\frac{{g}_{2}}{1+{g}_{2}}$$  0.69:1 

5  1  1  0  0  0  $$\frac{{g}_{2}}{{g}_{2}+1/\left(1+{g}_{1}\right)}$$  0.87:1 

4  0  1  1  0  0  $$\frac{{g}_{3}\left(1+{g}_{1}\right)}{{g}_{3}\left(1+{g}_{1}\right)1}$$  1.14:1 

3  1  0  1  0  0  $$\frac{1+{g}_{1}}{{g}_{1}}$$  1.50:1 

2  0  0  1  0  1  $$\frac{\left(1+{g}_{1}\right)\left({g}_{3}+{g}_{2}\right)}{{g}_{1}\left(1+{g}_{2}\right)}$$  2.31:1 

1  0  0  1  1  0  $$\frac{{g}_{3}\left(1+{g}_{1}\right)}{{g}_{1}}$$  4.12:1 

R  1  0  0  1  0  $$\frac{{g}_{2}\left(1+{g}_{1}\right)}{{g}_{1}}$$  3.36:1 

4Speed CRCR  4Speed Ravigneaux  7Speed Lepelletier  8Speed  9Speed