Mechanical Drives: Spur Gears

In a gear drive the ratio of the _____________ can be used to compute gear ratio.

• Pitch diameters

• Outer diameters

• The gear pitches

• Shaft diameters

The purpose of the idler gear is to either ____________ of the driven gear or transfer power to a location which is farther from the driver shaft.

• Increase torque

• Change the direction of rotation

• Increase Speed

• Decrease Speed

A gear drive has a 12-tooth driver gear and an 18-tooth driven gear. If the driver gear is rotating at 720 rpm the rotational speed of the driven gear will be ___________ rpm.

• 1080

• 680

• 480

• 280

The pitch of gear is the distance between ____________.

• The top point of each tooth to the corresponding point on the adjacent tooth

• The distance between two corresponding teeth located at the base of the teeth

• One point on a tooth and the corresponding point on the next tooth measured along the pitch circle

• The angle of the teeth between the top of the teeth and the base

A gear drive system using two spur gears connected by an idler gear is an example of a _________________ gear drive.

• Parallel axis

• Intersecting axis

• Non-Intersecting

• Moving axis

A rack and pinion drive is an example of a(n) ___________ gear drive.

• Parallel axis

• Intersecting Axis

• Non-intersecting axis

• Moving axis

One disadvantage of a helical gears is _____________________ .

• Excess noise

• Low effciency

• Side thrust

• Excess weight

Diametrical pitch is the ratio of _________________.

• The pitch diameter to the outer diameter

• Outer diameter to the base circle diameter

• Pitch diameter to the pitch

• Number of teeth to the pitch diameter

A gear with a diametrical pitch of 16 will mesh with ______________ .

• Any gear having a diametral pitch of 16 or lower

• Any gear having a diametral pitch of 16 or higher

• Only a gear having a diametral pitch of 16

• Only a gear having a diametral pitch greater than 16

Backlash is the ____________________

• Distance between the bottom land and the top land of a gear

• Difference between the thickness of a tooth and the width of the tooth space

• Working depth of a gear

• DIfference between the runout of two shafts having meshing gears installed on each shaft