1. Understanding Simple Machines
Levers
Inclined Plane
Wedge
Wheel and Axle
Screws
Gears
Pulleys
Cams
Machine Elements
Gadget Anatomy
Assembled by Craig Tillmann
from the following web sites:
Inventors Toolbox: The Elements of Machines
How Stuff Works
Explore Science
Beakman and Jax: Levers
Delightful Machines
Technology Education Home Page

2. Levers All levers have 3 parts: the fulcrum, the load, and the effort.
The fulcrum is the pivot point. When it's right in the middle of the lever, the amount of effort you push down equals the amount of load you can lift.
Learn more about levers
Water Powered Simple Machine

3. Moving the Fulcrum
Here the fulcrum is closer to the load. The distance from the effort end to the fulcrum is twice the distance from the fulcrum to the load. You only have to push down half as hard to lift the same weight. The trade-off is you have to push down a longer distance.

4. Classes of Levers
First Class
Second Class
Third Class

5. Inclined Plane
Examples of inclined planes:
Loading ramp
Stairs or wheelchair ramp
Mountain road
Threaded screw.
Inclined Plane Clocks
An inclined plane is a ramp used to reduce the effort needed to raise or lower an object over a vertical height.
Online Multimedia Activity
Requires Shockwave

6. Wedge
Nearly all cutting machines use the wedge.
A lifting machine may use a wedge to get under a load.
A wedge converts motion in one direction into a splitting motion that acts at right angles to the blade.

7. Wheel and Axle
A wheel or spoke is locked to a central axle so that when one is turned the other must turn.
A longer motion at the edge of the wheel is converted to a shorter more powerful motion at the axle.

8. Screws
Archimedes screw
A screw is a central core with a thread or groove(inclined plane) wrapped around it to form a helix. While turning, a screw converts a rotary motion into a forward or backward motion.

9. Gears
Bevel Gear
Rack and Pinion
Worm Gear
Learn more about Gears
Gears are toothed or pegged wheels meshed together to transmit motion and force.
The larger gear will rotate more slowly than the smaller one, but will rotate with greater force.
Each gear in a series reverses the direction of rotation of the previous gear.

10. Bevel Gear
Bevel Gears are Gears that mesh at an angle and change the direction rotation.

11. Rack and Pinion
A single gear, the pinion, meshes with a sliding toothed rack.
This combination converts rotary motion to linear motion.
Windshield wipers are powered by a rack and pinion gear.

12. Worm Gear combination of a gear meshed with the threads of a screw.
changes the direction of turning motion by ninety degrees.
decreases the speed of turning from screw to gear and increase its force.
Click Image for animation

13. Pulley System A single pulley reverses the direction of a force.
When two pulleys are connected, they permit a heavy load to be lifted with less force.
The trade-off is that the end of the rope must move a greater distance than the load.
Learn more about pulleys

14. Pulleys in Action

15. Cams A cam is a wheel with shaped bumps on it.
Cams are often connected to rods, levers, or springs.
gravity trip hammer

16. Cams at Work
A Crank Shaft changes the linear motion of the piston to a rotary motion.
A Cam Shaft is connected to the Crank by gears, belts or chains. It changes rotary motion to linear motion to open and close valves.

17. Other Elements of Machines
Crank and Rod
Ratchet
Chains and Belts
Connects two separated wheels so that when one turns, the other will turn in the same direction.
When the crank turns, the rod is pushed back and forth.
Allows a wheel to turn in only one direction. A bar called the "pawl" is fixed above the ratchet wheel.

18. Gadget Anatomy 1. Name the simple machines that make up each device.2. 3.