brake MITSUBISHI ECLIPSE 1990 Workshop Manual

21-72AUTOMATIC TRANSAXLE - Transaxle Control
_. --.
1st Gear (Selector Lever in “L”)
ReducingnLow-reverse brake
via 1
- 2 shift
valveLine pressure
Line
’pressureI1
Reducingpressure
N-R control , ,
vaive
16--.. -
1750090The low-reverse brake has the capacity that the
vehicle can be reversed at any point. Therefore, the
low-reverse brake operating pressure for the
“L”range is set to a level lower than that for
“I?” range.
This lower pressure is produced by reducing the line
pressure from the No. 5 port of the pressure controlvalve by a certain level before being delivered
frorthe No. 10 port to the low-reverse brake via the
1-lshift valve.
The method of regulation of pressure from the
No.:port to the No. 10 port is the same as that for
tht“Upshift” explained on the previous page.

AUTOMATIC TRANSAXLE - Transaxle Control21-73
‘elector Lever in “R”
Reducingvalve
ReducingTo low-reverse
OFF1750099
en the manual valve is shifted to the
“R” rangedirected to the low-reverse brake. Through this
ition, the pressure control solenoid valve func-pressure control, the shocks that would occur while
Ions under duty control from the transaxle controlshifting to reverse are minimized.
to reduce the reducing pressure in the No.23bOnce the low-reverse brake is engaged, the press-and to creaje another control. pressure in this
ure control solenoid valve is deenergized and normal
. The balance of forces established between thereducing pressure is reestablished in the No.23bntrol pressure and the force of the N-R controlline. Because this reestablished reducing pressure
Ivespring determines the degree that the No.9forces the N-R control valve toward the left, the line
e port will be open. The line pressure from thepressure passing through the No.9 port is applied
9 line is regulated by
passinq through the portdirectly to the low-reverse brake through the No. 16
ose opening has been adjusted and then isport and engages the brake with a strong pressure
force.

21-74AUTOMATIC TRANSAXLE - Transaxle Control
l-2 SHIFT VALVE
First SpeedTO low-reverse brake-Shift control(at “L” range)sorenotd valve “A’.4Shift control
l-2 shift
valve
ON !.IEXShift
coitrol
I/
EX1valve
From pressurecontrol valve
t(at “L” range)
Line pressureTo kickdown servo
l?zza.. -apply sidet
1750235
Second Speed
EX
” IIII2nd press.!iavalve
IFrom pressurecontrol valve
1750236The valve is actuated by the line pressure that has
been regulated by the shift control valve to change
the line pressure flow when .shifting is performed
between
1st and 2nd gears.
It also controls the hydraulic pressure passage to
the
low:-?everse brake when in the R (reverse) gear.
In
1st GearUpsh’ft from
1st to 2nd Gear
If the 2nd pressure from the shift control valve isdirected to the
l-2 shift valve through the No.6port, the pressure acts on the left end of the valve
causing it to move to the right, and the No. 11
poflcommunicating with the kickdown servo is opened
The line pressure coming from the pressure
controivalve through the No. 10 line is then directed to thekickdown servo via the No. 11 line.
In
2nd. 3rd and 4th gears, the 1-2 shift valve is
always held pushed to the right.
) ;‘I
I. 4The
1-2 shift valve is pushed to the left and held
there by the spring force when no pressure is
directed to the valve.
In the
“L” range, the line pressure from the
pressure control valve is directed to the low-reverse
brake by way of the No. 10 and No. 17 ports.
,i

AUTOMATIC TRANSAXLE - Transaxle Control21-75
From kickdown
servo apply side
1Shift control
valve
1-2 shift
1750237
11To low-reverse To low-reversebrake brake
‘1..‘; Line pressure.F: from manual valveDownshift from
2nd to 1st Gear
If the shift control valve is moved to the
1st gear position, the2nd pressure is released and the
l-2 shift valve is pushed to
the left by the spring force. This opens the exhaust port and the
pressrue that was acting on the kickdown servo is now
released through the No. 11 line.
In Reverse
When the manual valve is shifted to the reverse position, line
pressure is directed to the No. 16 port of the
1-2 shift valve by
way of the N-R control valve. The combination of a larger area
to which pressure is applied on the
#2 land and a smaller area
on the
# 1 land of the 1-2 shift valve causes the valve to move
to the right, thus opening the No. 17 line port.
Pressure is directed to the low-reverse brake through this
opened port.
-

21-80AUTOMATIC TRANSAXLE - Transaxle Control
VALVE WITH ORIFICE
When
oressureis releasedWhen pressure
-is applredTo rear clutch
via rear clutch
exhaust valveTo low-reverse brake
i
Ltne pressure1
- 2 shiftvalve
Ex
1750242If the accelerator pedal is depressed ‘immediately
after shifting the select lever from
“N” to “D”, the
rear clutch engages directly and the vehicle moves
in
1st gear. Due to the arrangement of the hydraulic
circuit, in thjs case, the hydraulic pressure is actuallydirected to both the rear clutch and the low-reverse
brake, thus dividing the quantity of the distributed
fluid. This in turn can cause a delay in clutchengagement when the fluid temperature is high. To
prevent this, a special valve is provided in the
low-reverse brake circuit. This valve has an orifice
which restricts flow of fluid when the pressure is
directed to the low-reverse brake but has no flow
restriction effect when the low-reverse brake press-
ure is released, thus preventing sluggish release of
the brake.

21-82AUTOMATIC TRANSAXLE - Transaxle Control
valve
A
2nd3rdpressure pressure175011:To shift
control
valve#3
land
2nd3rdpressure pressure
175011~LlUpshift from
2nd to 3rd Gear\(1) When the shift control valve comes into
3rd gear position
and the
3rd pressure is established, the pressure is
directed to the No.7 port of the end clutch valve through
the No.7 line. In this instance, the
3rd pressure is blocked
ahead by the end clutch valve and the check ball.
(2) If a shift to the
3rd gear is initiated, the pressrue begins to
be directed from the
2-3/4-3 shift valve to the front clutch
and the release side chamber of kickdown servo cylinder.
The same pressure also is directed to the chamber at the
right end of the end clutch valve through the No. 12 line.
During the shift to the
3rd gear, the pressure in the No. 12
line is regulated by the pressure control valve to a level
lower than the line pressure so that the No. 12 line pressureis not high enough to force the end clutch valve toward the
left.(3) Once the front clutch has been engaged and the kickdown
brake released, the No. 12 line pressure is raised to a level .
equivalent to the line pressure.
This means that the pressures at both ends of the end
j
clutch valve (or No. 6 line pressure and No. 12 line pressure)[are at the same level. However, as the area of the
#3 land
to which pressure is applied is larger than that of the
# 1
land of the end clutch valve, the valve is pushed to left, thusopening the No.
18 port. This allows the 3rd pressure (line
pressure) already established in the No. 7 line to be directedto the end clutch through
the..No.7 port. The end clutch is
now engaged.
Downshift from
3rd to 2nd Gear
(1) Both front clutch pressure and kickdown servo release
pressure are released, and therefore, the pressure in
theend clutch valve right end chamber is also released.
--
(2) This results in a rightward movement of the end clutclvalve by the
2nd pressure working on its left end, closingthe
No.7 port and releasing the end clutch pressurethrough the No.8 port. Now the end clutch is released,
I

AUTOMATIC TRANSAXLE - ~kmucle ControlHWBRAULIC
ClRCUlT
S.XTOR LEVER IN “N”Torque-converterKickdown servo
FrontRearu)w-reverse =.I 1~
clutchclutchbrakeclutch
r-m I
-amper clutchIhOlJenoid valve
Oil -filter,
IIShi LroI3,
Lii PressureTorque-converter pressureand
lubriition oil pressureReducing pressurePump suction pressure
Lii Pressure(control pressure)
PCSV control pressureDamper clutch pressure
DCCSV control pressure
I1760224
A

AUTOMATIC TRANSAXLE - Transaxle Control21-89
.LECTOR LEVER IN “D” (Stopping)Torqueconverter
/Klckdown servoFrontRearLow-reverseEnd
clutchclutchbrakeclutch
---
-Ln
r clutch
\ Mhm+oque-converterontrol
valve
IOil panI
N-Rcontrol valve18
U-D controlfalve
Pressurecontrol valveLine PressureTorque-converter
pressureand Jubrication oil pressureReducing pressurePump suction pressure= Line Pressure(control pressure)
PCSV control pressureDamper clutch pressure
DCCSV control pressure
1760246

21-90AUTOMATIC TRANSAXLE - Transaxle Control
SELECTOR LEVER IN
‘D” (1st Gear)Torque-converterFront
clutch
F1,/
RearLow-reverseEndclutchbrakeclutch
-m -Kickdown servosolenoid
valve
h
N-R control valve
El
U-D controlflalvePressurecontrol
valve
1 Oil panJLine
PressurePump suctiin pressureDamper clutch pressure
Torqueconverter pressureand lubrication oil pressureReducing pressurem Line Pressure(control pressure)
PCSV control pressure
= DCCSV control pressure_
1750247

AUTOMATIC TRANSAXLE - Transaxle Control21-91
.LECTOR LEVER IN ‘D” (2nd Gear)Torque-converter
FrontdutchKEkctown servoRearLow-reverseEnd
clutchbrakeclutch
ri
t
valr
hvalve
“II I
ON-II II
LOUpan)-
N-D controlvalve
Pressurecontrol valve
N-R control valve
118 Line Pressure
Torqueconverter pressureand lubrication oil pressure
m Pump suction pressure
m Line Pressure(control pressure)Damper clutch pressurem DCCSV control pressureReducing pressure
PCSV control pressure