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Flashcards in Actuator Fundementals Deck (20)
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1

Telescoping single acting cylinder

-Largest section moves first
-Only be used when load never goes over centre
-Oil generally comes in rod as mounted upside down compared to highway

2

Cylinder seals may consist of

Leather
Polyurethane
Nitrile
Viton

3

What are wipers used for

Prevent contamination from entering cylinder when rod is retracted

4

Telescoping double acting cylinder

Has 2 ports
High pressure seals facing both ways inside

5

Piston relief valve

Are small poppets that are held closed when high pressure oil is applied to move the rod, when the rod bottoms the poppets are forced opened allowing oil to flow to reservoir limiting pressure

6

Cylinder cushion

Used to slow down the rod as it approaches end of travel
Meter the oil leaving the cylinder to slow its speed

7

Quick drop valve

Used in regeneration
Allow oil for the rod end of cylinder to enter the base end a device is being lowered to speed up drop time.
Used on dozer blades and scraper bowls

8

Regeneration

The process of using oil that is being returned to tank from the rod end of cylinder to help fill the base end and allow blade to drop to ground faster

9

Speed of a motor is dependent on what

Inlet flow rate
Motor capacity

10

Amount of torque generated by motor is determined by what

Motor displacement
Motor inlet pressure

11

Gerollor and gerotor motors are used where

High torque, low speed operation

12

Gerotor

Cam ring is held stationary
Spool and gear are mounted together

13

What is the purpose of the roller inserts in a geroller motor

Provide better wear characteristics
Reduced internal resistance

14

What is common swash plate angle in a piston pump

6.5 degrees
19 degrees

15

How can you tell axial motor from pump pressure plate

Pumps have up to 2 fishtails
Reversible motors have 4 fishtails
Inlet may not be re-enforced on pump

16

Why is axial piston shoe balanced

So as not to mill the shoe

17

2 speed motor are normally in what position

Max torque

18

What motors are normally in the max speed posistion

Fully pressure compensated motor

19

Crankshaft type radial piston motor

The pistons do not rotate, only move up and down
Spool sends oil to top of piston and pushes piston down on side of crank

20

Cam type radial piston motor

Pistons rotate with manifold
Cam is held stationary
High torque motor