Final

Question 1

level switch

Answer 1

wants to know level of fluid

Question 2

proximity switch

Answer 2

• non contact

- three kinds: inductive (ferrous objects), ultrasonic, and capacitance (non-ferrous)

Question 3

off delay timer switches

Answer 3

delay only when they are deenergized

Question 4

cushion spear/sleeve

Answer 4

tiny flow control valves inside of a cylinder

Question 5

emergency switch

Answer 5

• keeps circuit safe
• will stop circuit in middle of cycle
• cycle stop will wait until cycle has ended

Question 6

flow control valves need to be as close as possible to cylinder:

Answer 6

difficult to control air because air is very compressible

Question 7

pressure switch

Answer 7

• turns compressor on/off

- if it fails, safety relief valve kicks in and sends air to the atmosphere

Question 8

pressure regulator

Answer 8

usually set around 120 psi because it doesnt need very high pressure

Question 9

pneudraulics

Answer 9

smooth movement of hydraulics with cheapness of pneumatics

Question 10

determining compressor size

Answer 10

• add up all airflows needed for all cylinders and motors
• have some stand by capacity
• be ready for future expansion

Question 11

sizing of volume or receiver tank for compressor

Answer 11

use a nomograph

Question 12

dryers

Answer 12

• water is the enemy

- volume tank has manual/automatic drain

Question 13

3 types of dryers

Answer 13

• absorption: uses chemicals that absorb water (LiCl2, Al2O3)
• adsorption: keeps water on surface, uses silicon gel
• refrigerant type dryer (heat dryer)

Question 14

FRL

Answer 14

filter, regulator, lubricator

Question 15

Bernoulli’s law

Answer 15

velocity goes up so pressure goes down

Question 16

max vacuum pressure

Answer 16

30” Hg

Question 17

air motor types

Answer 17

• radial/axial piston
• sliding vane
• gear

Question 18

couple

Answer 18

two forces that are equal and opposite but not in line

Question 19

types of non-contact sensors

Answer 19

• photo eye
• proximity: inductive, capacitance, ultrasonic
• pressure switch/temperature switch
• level switch

Question 20

contact sensor

Answer 20

limit switch

Question 21

photo eye scanning methods

Answer 21

• opposed scanning: one side is a transmitter, one side is a receiver, they must line up perfectly
• reflective scanning: transmitter sends beam to reflective surface and reflective sends back to receiver
• diffused scanning: transmitter sends beam to object and object acts as reflective to send beam back to receiver

Question 22

receiver side: how does it work

Answer 22

• photo resistor: when light hits it, resistance changes
• photo diode: when light hits it, it conducts
• photo transistor: when light hits base, it conducts
• photo voltaic: has voltage when light hits it

Question 23

detent

Answer 23

a small spring that prevents spool from accidentally shifting

Question 24

relay

Answer 24

a transfer device for electrical energy, consists of a coil and contact(s)

Question 25

holding relay principle

Answer 25

coil relay is locked in through its own contact

Question 26

manual mode

Answer 26

- operator can control certain components without circuit automatically operating - beneficial for troubleshooting - operator must push jog buttons to turn on certain devices - if on auto, these buttons are locked out

Question 27

guard door

Answer 27

put around circuit, if guard door is open = circuit wont work

Question 28

rules for electrical circuit design

Answer 28

- push buttons and contacts always go on the hot side (left) | - solenoids, relays, lights, etc. always go on the cold side (right)

Question 29

center drill vs regular drill

Answer 29

center drill drills a hole into the object and then regular drill drills the rest of it

Question 30

5 ported valves

Answer 30

use 5 ported valves to control speed

Question 31

venturi suction cup

Answer 31

creates a vacuum which creates a suction cup grip = picks up/lets go of part

Question 32

hydraulic servo valve

Answer 32

- directional and flow control valve | - can position spool anywhere in stroke

Question 33

desirable features of pneumatic systems

Answer 33

cleanliness, high speeds, temperature stability, and overload safety

Question 34

undesirable features of pneumatic systems

Answer 34

cost, force, compressibility, and lubrication

Question 35

3 types of compressors

Answer 35

reciprocating piston, diaphragm, and slide vane rotary