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Flashcards in Powershift Mechanical & Electronic Components Deck (19):
1

What are the 2 general categories of powershift trans applications

Cycling
Hauling

2

What are 2 general categories of powershift trans designs

Planetary
Countershaft

3

Powershift

Speed and direction changes made solely by operator

4

Automatic

Makes speed changes are made independent from operator. all operator chooses is reverse or top gear

5

Cycling application

Trans has an equal # of forward and reverse gears, commonly used is machines that do repeated back and fourth movements

6

Hauling application

Commonly use an automatic transmission. When a machines work is usually loading a one place and driving to another location

7

Cycling trans clutches

Cycling trans usually the same clutches in F and R

8

Differential planetary set

A simple planetary set with three rotating members which can have dual inputs and a single output

9

Dual input planetary

The Carrier speed will always be somewhere between the speed on the sun gear and the internal gear

10

Tooth speed carrier rotation

Carrier will rotate the direction of the input gear with the highest tooth speed

11

Tooth speed

Refers to the number of gear teeth that pass by a given point in a given period of time, measured in teeth per second (t/s)

12

Clutch discs

Steel discs that have a friction material bonded onto both surfaces of the disc. Use sintered bronze, or composite materials
Have ridges in discs for lubrication called lands

13

Clutch plates

Located between every pair of clutch discs
Usually have tangs on outside to lock to case housing

14

Clutch pistons

Lip type seal, o-ring and teflon seals are used to seal.
Lip type is more commonly used in automatic for full sealing, teflon can be used in big powershift where some leakage can be handled

15

The major advantage of a powershift or auto trans over a manual trans is

Power flow is not interrupted when shifts are made

16

4 advantages of planetary gear set over spur gear sets

Gears in constant mesh - no grinding gears
Smaller and more compact
Radial and axial loads are offset in planetary
capable of providing many gear combinations

17

What are 2 functions of the lands on a clutch disc

Carry oil to lube the discs when the clutch is disengaged
Allow oil to be squeezed out when the clutch is applied

18

Carrier does what when internal and sun gear are rotating forward at same speed.

Reduction

19

What are 3 characteristics of the clutches used in a planetary transmission

Multiple disc type
Applied with oil pressure
Spring released