190303C Flashcards
What is the point of a PTO?
Auxiliary power can be drawn off to drive other components
How does a powershift transmission select gears?
The operator solely selects gear range, F R and N
What does the operator have to input to make changes in an automatic transmission?
Select highest gear and direction
Which type of transmission is used in a cycling application?
Power shift
Automatic transmissions work best in what type of application?
Hauling application (more forward than reverse)
What do most of heavy equipment transmissions have for gear sets?
Planetary
What are the advantages of planetary gear sets?
No grinding or missed shifts
smaller/more compact
small bearings/thrust washers
Extremely versatile
What are three basic components to a planetary?
Sun
Internal
Planetary pinion/carrier
How are the teeth cut on planetary gear sets?
Straight or helical cut
What changes when more planetary pinions are added to a gear set?
More torque can be transmitted
What are five conditions of a simple planetary?
Reduction in Reverse Reduction in Forward Direct Drive Neutral Over drive in both directions
Is input turning faster or slower in a reduction condition?
Faster than out put speed
Whats an example of a gear ration in an overdrive?
0.33:1
What must happen to transmit power in a simple planetary?
One member driving
one member driven
one member help (reactionary)
When two external gears are rotating in mesh what direction does the driven gear turn?
Opposite to the drive
How do you achieve the deepest reduction in a simple planetary?
Input on the sun
Output on the carrier
How is reverse achieved in a simple planetary?
The planet carrier must be held
Other than holding two planetary members together is there another way to achieve direct drive?
Yes, in a dual input planetary two members being driven at the same RPM
If the internal gear and sun are held together what will happen to the speed of the carrier output?
Carrier output speed will be in between the input speed of the sun and internal gear
What three shafts are connected to planetary members in a planetary transmission?
turbine shaft
mainshaft
output shaft
What does a stationary clutch lock?
a planetary member to the transmission housing
What does a rotating clutch connect?
Two rotating components
Describe tooth speed
Refers to the number of gear teeth passing by a given point in a given period of time and is measure in teeth per second (t/s)
What is the result of the internal gear and the sun gear being rotated in opposite directions?
hint: in relation to speed
The carrier output speed decreases
RPM and t/s are the same?
Nope
What is the most common type of clutch assembles?
multiple disc
True or False: Coolant contamination is not a problem in clutch assembles.
False
What is more likely to be able to be repaired after a gear fails, automatic or countershaft?
Countershaft
Two planetary gear sets are arranged as a multiple combination: Input power is supplied to the sun gear of the first set and its internal gear is held. The output of the first gear set feeds the sun gear of the second set. What is the result if the second set internal is held?
The output is the planet carrier. Double reduction
Two planetary gear sets are arranged as multiple combination: Input power is supplied to the carrier of the first set and the sun is held. The output of the first gear set feeds the carrier of the second set. What is the result if the second sun is held?
double over drive
Internal gear is rotating in reverse at a much higher tooth speed than the sun gear is rotating forward. What is the result?
Reverse
Internal gear and planet carrier are traveling in the same direction at the same RPM. What is the result?
Direct Drive
Internal gear is turning at a lower tooth speed than the sun in the same direction. What is the result?
Reduction
Internal gear is turning opposite to the sun gear at a higher tooth speed. What is the result?
Reverse
Internal gear is turning in the same direction as the sun at a higher RPM. What is a result?
Over Drive
