الثلاثاء، 14 مايو، 2013

gearbox of tractor puma 210hp


 Gearbox overview

Splitter clutches A-B
Gear clutch C-D-E
Range clutch  F1-F2- F3-R
Clutch 40km ECO 50Km (19th Gear)
Clutch FWD
Clutch PTO                      


                Gears v clutches
9 Electro-hydraulically operated clutches
A, B clutches – Provide high and low output ratios to “speed” section of gearbox.
C, D, E clutches – Provide 6 speeds in conjunction with A and B clutches.
S (slow), M (medium), F (fast) and R (reverse) are Range clutches.


Power Flow
5 major groups of components transfer drive from the engine to the rear axle.  This diagram shows the R clutch assembly and idler gear on top of the gearbox for clarity although in reality these are on the right hand side in the gearbox.
Drive is transferred from the input shaft to the blue components either directly ( if clutch A is engaged ) or via the yellow components  ( if clutch B is engaged ).
The blue components are coupled to the green components via clutches C, D or E.  When either A or B plus C, D or E are engaged, all the green components will be rotating.  Note that the M clutch assembly is permanently meshed to the R clutch assembly so when reverse is engaged, the M clutch assembly is being used as an idler gear. 
The green components are linked to the purple components through clutches S, M, F and R.  Note that when S ( slow ) is engaged, the drive is transferred through the M and R clutch assemblies and back through an idler gear to achieve forwards.
Feathering of drive is controlled by the Range clutches ( S, M, F, R )
Schematic of Clutch pack usage
Power Flow - 1st gear
Engage A clutch
Engage C clutch
Through M clutch assembly
Through R clutch assembly
Through idler gear
Engage S clutch
Output shaft to rear axle

 Power Flow - Reverse 5th gear
Engage A clutch
Engage E clutch
Through M clutch assembly which acts as an idler gear
Engage R clutch
Output shaft to rear axle 
3D of Speed Gears


3D of Range Gears
Torque sensing damper disc
( Shown looking backwards towards the transmission )
 Flywheel lug ( 1 ), Torque / rpm sensor ( 2 ), Transmission input shaft ( 3 ), Damper disc finger ( 4 ), Damper disc spring ( 5 )
Drive from the engine transferred to the flywheel ( 1 ) which has 4 lugs on its outer edge
Drive between flywheel and damper disc transferred through the damping springs ( 5 ), through the damper disc to the transmission input shaft ( 3 )
Damper disc has 4 fingers ( 4 ) which are riveted to its rearward side
As the transmission spins, the torque / rpm sensor ( 2 ) emits a signal every time a damper disc finger or flywheel lug passes it.
No load
The damping springs will transfer drive without being compressed
The short signals produced by the torque / rpm sensor will be half way between the long signal produced by the lugs.

Maximum Torque
The damping springs will be compressed as the engine “pushes” the transmission round. 
The short signals produced by the torque / rpm sensor will be shortly before the long signal produced by the flywheel.
As the torque increases, there will be less time between the damper disc signal and the flywheel signal
In this way the processor knows the amount of torque being transferred through the transmission
 Overspeed 
The damping springs will be compressed as the transmission is “pushing”  the engine to go faster e.g. when driving down a hill with a heavily loaded trailer 
The short signals produced by the torque / rpm sensor will be shortly after the long signal produced by the flywheel.
As the torque increases, there will be less time between the flywheel signal and the damper disc signal
 In this way the processor knows the amount of torque being transferred back to the engine

TM Transmission Top Cover
1. From steering pump flow divider (lubrication oil)
2. Return from steering motor
3. To oil cooler
4. Return from oil cooler
5. Supplementary lubrication oil from charge circuit
6. To lubrication circuit
7. Low pressure feed for transmission
8. Feed to 19th gear dump solenoid
9. Low pressure supply to brake booster circuit
10. Low pressure oil – low pressure warning switch
11. Transmission oil temperature sensor
12. Range clutches pressure sensors
A. Transmission Clutch A solenoid
B. Transmission Clutch B solenoid
C. Transmission Clutch C solenoid
D. Transmission Clutch D solenoid
E. Transmission Clutch E solenoid
M Medium Range clutch solenoid
F High range clutch solenoid
S Low range clutch solenoid
R Reverse range clutch solenoid
19 19th gear clutch solenoid (50Km/h)

T7000 Transmission Top Cover
Revised pipe routing and connections
Switches have changed position
Transmission oil flows
Make reference to slide 16 ( PWM manifold ) and 17 ( Top cover schematic ).
Clutches A, E, M  ( 11th gear ) supplied with low pressure oil ( 16 - 18 bar ) via manifolds.  Oil ways in manifolds separated by sealing rings.
All other clutch oil ways open to sump and have no residual pressure
NB: In neutral, approx. 4 bar of pressure is supplied to the C, D and E clutches.  This locks the gearbox to prevent spin / creep.
Transmission lubrication circuit
Oil supplied by the steering pump.
Over pressure is controlled by lubrication relief valve
Supplied to moving components via manifolds and internal galleries within the gearbox shafts.