Quiz - Gears & Variable Speed Drives

Question 1

The distance from the centre of one tooth to the centre of the next tooth, measured along the pitch circle, is called…

a) diametral pitch
b) pitch diameter
c) circular pitch
d) outside diameter

Answer 1

c) circular pitch

Question 2

With an internal spur gear and pinion drive, the shaft centre lines are…..

a) compounding
b) crossing over at 90 degrees
c) intersecting at 90 degrees
d) parallel

Answer 2

d) parallel

Question 3

The input gear of the train has 32 teeth turning at 32rpm; it is connected to the 24 tooth output gear through a 16 tooth idler. What is the end result?

a) speed reduction, rotation change
b) speed increase, rotation change
c) speed reduction, no change in rotation
d) speed increase, no change in rotation

Answer 3

d) speed increase, no change in rotation

Question 4

Angular bevel gears are also known as…

a) mitre
b) spiral bevel
c) straight bevel
d) zerol

Answer 4

c) straight bevel

Question 5

Mitre gears have…..

a) the same number of teeth
b) shafts that cross over at 90 degrees
c) spiral cut teeth
d) varying ratios

Answer 5

a) the same number of teeth

Question 6

The worm and worm wheel gears…..

a) have low sliding action
b) are of opposite hand
c) have parallel shafts
d) are of the same hand

Answer 6

d) are of the same hand

Question 7

Of the following variable speed drives, which one would require a heat exchanger?

a) scoop tube
b) torque converter
c) variable speed chain drive
d) wet disc

Answer 7

d) wet disc

Question 8

A compound gear reducer will have a minimum of…..

a) 2 shafts
b) 3 shafts
c) 4 shafts
d) 5 shafts

Answer 8

b) 3 shafts

Question 9

The tie rod should be kept as near as possible to a _____ line running from the output shaft to the point of attachment.

a) 80°
b) 180°
c) 60°
d) 90°

Answer 9

d) 90°

Question 10

The distance that one tooth on the worm advances in one turn is the…..

a) lead
b) pitch
c) pressure angle
d) helix angle

Answer 10

a) lead

Question 11

Gears that have no effect on gear or speed ratios in a gear train are…..

a) pinion gears
b) idler gears
c) spur gears
d) internal gears

Answer 11

b) idler gears

Question 12

Of the following, which one would best describe a mitre gear box?

a) shafts intersecting at 45° and same # of teeth
b) shafts intersecting at 45° and a different # of teeth
c) shafts intersecting at 90° and same # of teeth
d) shafts intersecting at 90° and a different # of teeth

Answer 12

c) shafts intersecting at 90° and same # of teeth

Question 13

To obtain the greatest area of tooth contact in a worm and worm gear, use…..

a) non throated gear set
b) single throated gear set
c) double throated gear set
d) four start non throated gear set

Answer 13

c) double throated gear set

Question 14

On a worm, the lead is equal to…..

a) the pitch
b) the pitch times number of starts on the worm
c) the pitch times the ratio of the gears
d) the pitch times the # of teeth on the worm wheel

Answer 14

b) the pitch times number of starts on the worm

Question 15

To obtain backlash readings we could use…..

a) the bump check
b) a dial indicator
c) Prussian blue
d) a torque wrench

Answer 15

b) a dial indicator

Question 16

Which of the following types of gears does not produce axial thrust on the shaft?

a) double helical
b) hypoid
c) spiral bevel
d) worm and worm wheel

Answer 16

b) hypoid

Question 17

A non-throated single start worm gear set, has…..

a) the strongest tooth mesh
b) higher contact pressures than a similar sized double throated worm and gear
c) the highest gear ratios
d) the most teeth in mesh

Answer 17

b) higher contact pressures than a similar sized double throated worm and gear

Question 18

The diametral pitch of a gear is…..

a) the circular pitch times number of teeth
b) the distance from one tooth to the next, measured along the pitch line
c) the number of teeth per inch of pitch diameter
d) the ratio of number of teeth to pitch circle

Answer 18

c) the number of teeth per inch of pitch diameter

Question 19

The clearance between mating teeth of gears at the pitch line is called the…..

a) backlash
b) clearance
c) circular pitch
d) diametral pitch

Answer 19

a) backlash

Question 20

The ratio through a single reduction worm gear set is determined by the number of…..

a) starts on the worm
b) teeth on worm divided by number of teeth on gear
c) teeth on gear times number of starts on the worm
d) teeth on gear divided by number of starts on the worm

Answer 20

d) teeth on gear divided by number of starts on the worm

Question 21

The mesh pattern on a non-throated worm reducer is changed by…..

a) increasing input rpm
b) removing the backlash
c) adding or removing shims on the worm shaft bearing end caps
d) adding or removing shims on the worm wheel bearing end caps

Answer 21

d) adding or removing shims on the worm wheel bearing end caps

Question 22

The output speed of a reducer is determined by…..

a) size of the input shaft
b) input and the type of the gears
c) input speed and the gear ratio
d) horsepower rating

Answer 22

c) input speed and the gear ratio

Question 23

The direction of axial thrust in a parallel shaft helical gear set depends upon…..

a) direction of rotation
b) helix angle
c) shaft speed
d) sliding action

Answer 23

a) direction of rotation

Question 24

When referring to a gear tooth, the working depth consists of…..

a) addendum plus dedendum
b) whole depth mines dedendum
c) addendum plus dedendum minus clearance
d) whole depth plus clearance

Answer 24

c) addendum plus dedendum minus clearance

Question 25

Standard gears are available in 14.5° and 20°, these refer to…..

a) the helix angle
b) the crown angle
c) the pressure angle
d) the tapered bore

Answer 25

c) the pressure angle

Question 26

Variable speed belt drives change speed based on the principle of…..

a) varying belt lengths
b) varying belt width
c) varying input speed
d) varying effective sheave diameters

Answer 26

d) varying effective sheave diameters

Question 27

The metal chain variable speed drive is also known as…..

a) positive infinitely variable
b) post internally viable
c) primary internally variable
d) progressively independently variable

Answer 27

a) positive infinitely variable

Question 28

To adjust the speed of a variable speed belt drive, you…..

a) make adjustments when running
b) make adjustments when stopped
c) change to a longer or shorter belt
d) adjust the motor speed using a V.F.D.

Answer 28

a) make adjustments when running

Question 29

In order for helical gears to have parallel shafts they must…..

a) be opposite hands
b) be the same hands
c) have unequal pressure angles
d) have unequal helix angles

Answer 29

a) be opposite hands

Question 30

Of the following, which one will allow for a straddle mounted pinion gear?

a) straight bevel
b) spiral bevel
c) hypoid
d) zerol bevel

Answer 30

c) hypoid

Question 31

The input on a compound gear reducer has a 10 tooth gear driving a 50 tooth gear; the final reduction has an 8 tooth gear driving a 32 tooth output gear, what is the total reduction?

a) 1.5:1
b) 9:1
c) 18:1
d) 20:1

Answer 31

d) 20:1