ILM 190303 B Flashcards
What is Hydrodynamic Drive?
The process where fluid is used to transfer power.
What is a Fluid Coupling?
The method where two spinning objects are transferring power by Hydrodynamics.
What is the impeller connected to?
The input shaft from the engine.
What is the turbine connected to?
The output shaft to the transmission.
What are some advantages of fluid couplings?
No mechanical linkage, shock absorption, gradual application of torque.
What are some disadvantages of fluid couplings?
Energy loss due to slippage, excessive heat production.
What are the two types of fluid flow within a torque converter?
Vortex and Rotary Flow
What are the characteristics of Vortex flow?
When the turbine is moving slower than the impeller producing high heat, low speed and high torque.
What are the characteristics of Rotary Flow?
When the turbine and impeller are moving generally the same speed, producing high speed and low torque.
What is the Split Guide Ring used for?
To prevent turbulence between the oil.
What is the purpose of a stator?
The stator redirects the flow of the oil towards the impeller to be multiplied.
What are the two types of stators?
Fixed and Freewheeling
What are some characteristics of a fixed stator?
It is fixed to the housing and prevents rotary flow.
What are some characteristics of a freewheeling stator?
This utilizes sprag overrunning clutches to unlock the stator and allow rotary flow when the turbine matches impeller speed.
What are the three phases in a torque converter?
- Converting Phase where the turbine is moving slower than the impeller.
- Coupling Phase where both move at the same speed.
- Lockup where both are locked with clutches.
What are stages?
How many times the oil gets redirected to the turbine before it returns to the impeller.
What is stall speed?
The largest difference in speed between the impeller and turbine. The turbine would not be moving.
What is a variable pitch stator?
A stator where the blades can change position as torque is required.
In what positions does a variable pitch stator produce the most and least amount of torque?
The most is achieved in the open blades position.
The lease is achieved in the closed blades position.
At what temperature does transmission oil begin to break down?
121 Decrees Celsius or 250 Fahrenheit
What two types of housings are used in torque converter design? What is one big difference?
Dry housings that are sealed
& Wet Housings that incorporate PTO’s
What is the difference between a torque converter and a torque divider?
A torque divider utilizes a planetary gearset.
How is a torque divider connected inside?
Impeller to Sun
Turbine to Ring
Planetary Carrier to Output
What produces a high stall speed upon test?
Torque converter not working, or Transmission clutches slipping.
What produces a low stall speed upon test?
Torque converter freewheeling stator failing. No torque being developed.
How do you perform a leak test on a sealed dry housing?
Submerge in liquid and pressurize to 70 PSI.
What is the most important step after installing a torque converter?
Check crankshaft endplay.
