PLTW Robotics Test

What is the output movement of a rack and pinion

linear

what is a leadscrews output movement?

linear

What types of mechanisms change direction?

meshed gears and output shafts

Input movement of a crank and slider

rotary

What is the input movement of a rack and pinion

rotary

input movement of a Cam and Follower

rotary

what is a leadscrews input movement?

rotary

a rack and pinion are used to convert between ____ and _____ motion.

rotary and linear

Universal joints are used to transmit ______ movement at an angle that is not ___°.

rotary movement at an angle that is not 90°

a leadscrew Changes _____ movement into _____ movement

rotary to linear

As a cam rotates, the flat follower is raised and lowered, converting _______ motion to _______ (back and forth) motion.

rotary to reciprocating

The bevel gear is used to change_______ motion at an angle.

rotational

An Idler Gear allows the drive and driven gears to rotate in the ____ direction.

same

Shaft direction in a chain drive

same

input & output gears in a Simple Gear Train with idler goes in the _____ direction

same

universal joints in input and output shafts

same direction

what direction does the open belt go in the belt drive

same direction

Using gears with differing numbers of teeth will change the ____ and ____.

speed and torque

In the bevel gear, if input is < output what happens?

speed decreased torque increases

what is smaller in a chain drive

sprocket

Where do you find a pulley and belt?

Lawn mower, car engine

Follower moves up and down _ times for every revolution of the crank in the cam and follower

1

ratio of a chain drive

18:30 or 3:5

A Simple Gear Train ratio is ?:?

1:1

A Simple Gear Train with idler ratio is ?:?

1:1

Ratio of a universal joint

1:1

ration in the belt drive

1:1

In the bevel gear, what is the gear ratio?

1:2

slider moves of a crank and slider

2 inches

in the worm and wheel what is the gear ratio?

24:1

A Ratio in a Simple Gear Train is __Teeth:__ teeth or _:_

36 teeth:60 teeth or 3:5

how many revolutions does a leadscrew have?

4.75

what direction is the Worm and Wheel

90 degree angle

Angular range of a universal joint

>90 <270

What is a Mechanism?

A mechanism is the part of a machine which contains two or more pieces arranged so that the motion of one compels the motion of the others

Where do you find a chain and sprocket?

Bicycle and motorcycle

Where Do You Find a Cam and Follower?

Cam shaft

Speed in a Simple Gear Train with idler is

Constant

Where can you find a universal joint?

Drive shaft of vehicles, power take-off

Where can you find the bevel gear

Hand drill, car differential, shaft-driven bicycle

Where do you find a lead screw?

Jack, vice

The motion is _________ ; a gear cannot drive a worm.

NOT REVERSIBLE

Where Do You Find a Simple Gear Train with Idler?

Paper transport rollers

Input and output shafts in a Simple Gear Train with Idler are

Parallel

Why would you use belts instead of chains

Quieter and less expensive

What happens because the larger drive pulley in the belt drive

Speed - increased Torque - decreased

Where Do You Find a Crank and Slider?

Steam train, internal combustion engine.

______ is a push or pull in a circular direction

Torque

Advantage of Chain and Sprocket over spur gears

Transfer torque and speed over long distances

Where do you find worm and wheel

Tuning mechanisms on string instruments, electric motors, winch

Where do you find a rack and pinion?

Used in steering systems to convert the rotary movement of turning the steering wheel into linear motion in wheels

Where do you find a simple gear train?

Watches, sewing machine, motor

What direction is the bevel gear in

angled

Speed and torque in a universal joint

constant

Speed in a Simple Gear Train is

constant

Torque in a Simple Gear Train is

constant

speed in the belt drive

constant

torque in the belt drive

constant

Torque in a Simple Gear Train with idler is

constatnt

In the bevel gear, torque is

decreased

Torque is _____ in a Simple Gear Train

decreased

in the Worm and Wheel speed is

decreased

torque of a chain drive

decreased

Simple gear train without idler gear

different directions

A _____ is a push or pull in a straight line

force

in the leadscrew _____ is increased

force

In the bevel gear, speed is

increased

Speed is _______ in a Simple Gear Train

increased

in the worm and wheel torque is

increased

speed of a chain drive

increased

increased crank of a crank and slider

increased distance slider moves

a leadscrew Significantly ______ force

increases

Flow of power of a crank and slider

not reversible

direction of travel in the cam and follower

not reversible

flow of power in the cam and follower

not reversible

in the worm and wheel the flow of power is

not reversible

the flow of power in a leadscrew is _________

not reversible

Gear direction in a Simple Gear Train is _____

opposite

Two meshed gears will rotate in _______ directions

opposite

what direction does the crossed belt go in the belt drive

opposite

What are the types of movement

oscilating rotary linear and reciprocating

If the _____ Gear is larger than the _____ gear the speed will decrease but the torque will increase

output gear is larger than the input

If the ______ gear is smaller than the ______ gear the speed will increase but the torque will decrease

output gear is smaller than the input

Gear ratios compare the ________ to the ________

output to the input

Angle of a chain drive

parallel

Input and output shafts in a Simple Gear Train are

parallel

What is the shaft in the belt drive

parallel

output movement of a Cam and Follower

reciprocating

output movement of a crank and slider

reciprocating

A worm is used to ____ speed and _____ torque.

reduce and increase

Flow of power in a Simple Gear Train is _______

reversible

Flow of power in a Simple Gear Train with idler is _______

reversible

Flow of power in a universal joint

reversible

In the bevel gear, what is the flow of power?

reversible

What is the direction of power of a rack and pinion

reversible

What is the flow of power in a rack and pinion

reversible

in the leadscrew direction of travel is _______

reversible

in the worm and wheel what is the direction of travel?

reversivle

what will happen to a rack and pinion with a larger pinion gear

the rack will move a longer distance

How can gear ratios be determined?

using the number of teeth or the diameter of the gear