Three of the six simple machines used by many engineers are taught to students: the lever, pulley, and wheel-and-axle. Although these devices were not especially difficult to make, they did require some skill to use correctly.
The second group of three is much more complicated machine than the first. They are the engine, pump, and fan. An engine is a mechanical device that uses heat added to a fluid (gas or liquid), which is then expanded to produce work. Engines can be split into two groups: expansion and compression. The expansion engine expands gas trapped in a balloon or similar object through the action of a piston. The compression engine compresses gas under pressure to increase its temperature so that it can be expanded later. The third type of engine is called a rotary engine because it includes parts that rotate around an axis. These parts may be cogs on a gearwheel or cylinders in an engine block. Rotary engines are still used today in some small engines such as lawnmowers and chain saws.
Pumps take energy from one place and move it someplace else. Pumps can be divided into two groups: external and internal. External pumps use energy from outside sources such as motors or windlasses. Internal pumps use energy stored within the body of the pump itself.
This is the fifth and final installment of our hands-on Simple Machines science program. We discussed the six basic machines in this Levers and Pulleys Simple Machines Lesson: inclined plane, wheel and axle (with a close-up on gears), screw, wedge, lever, and pulley.
In addition to these six machines, there are many other complicated mechanisms that use parts of these machines as building blocks. For example, a jack uses two wheels and an axis to create an inclined plane. A crane uses a hoist rope with a hook at the end to accomplish the same thing as a lever! And a vacuum cleaner uses a motor with a fan and a series of tubes called "wires" to pull dust into a container through a power suctioning action similar to a pulley system.
Simple machines provide us with the foundation for more complex machines. As we have seen, each machine has its own unique purpose in life. An airplane needs many different parts to work together: wings, engines, seats, etc. Without all of these parts, the airplane would not be able to fly. The same is true for any complex machine: it is made up of many different parts working together to achieve one goal.
In conclusion, simple machines are very useful tools for creating more complex machines. Each machine has its own special purpose for which it was designed. By understanding how these machines work, we can better understand how complex machines function.
(Hand out the Reference Sheet for Simple Machines.) The six simple machines are as follows: a wedge, a wheel and axle, a lever, an inclined plane, a screw, and a pulley. Do you identify any of these basic machinery now that you've seen the pictures? Is it possible to spot any of these small machinery around the classroom? How do they function? What are some examples of their use in industry?
Students should be able to identify each type of simple machine now that they have seen the pictures. They should also be able to describe how each works mechanically. Finally, they should be able to give some examples of applications of simple machines in industry.
Simple machines are useful tools for engineers to understand how objects work. Engineers can use this knowledge to design new products that cannot be done with other types of machinery. For example, an engineer could use a lever to lift heavy objects or an axel to make things rotate quickly. Modern products such as computer printers and photocopiers use several different types of simple machines together to create larger objects or components that could not be made easily or at all with one type of machine. For example, a printer engine uses several screws and wheels to produce printed pages.
The study of simple machines is called mechanical engineering. This field involves using science and math to build devices that produce power, move objects, or perform another function.
Humans have created technologies and tools to make labor simpler since the beginning of time. The inclined plane, the wheel and axle, the pulley, the lever, the screw, and the wedge are the most prominent of these. They are called "simple machines."
These six machines have one thing in common: they can be used to reduce work. A lever can be used to lift weights or a screw can be used to drive gears. A human-made device that uses one or more of these six principles is called a "mechanism."
Even though humans have been using these devices for thousands of years, scientists have only recently started studying them scientifically. Modern engineers use mathematical models to design new mechanisms and products that use these simple machines.
The inclined plane, lever, wedge, wheel and axle, pulley, and screw are examples of basic machines. Although they are all called "simple" machines, not all simple machines are alike. Each one has a purpose that makes it useful in certain situations but not others.
Inclined planes and levers can be used to lift or move objects with ease. They are called "simple" because you can understand how they work by thinking about what would happen if a human being made a small model of them. The idea is that you could use these machines to lift heavy items by making several small ones work together or to open or close doors by using levers on both sides of a doorframe.
Lawsons's book calls wheels, axles, and gears "complex machines". They are more complicated than inclined planes or levers because you can't easily build them yourself from common materials. However, they are also more useful because they can do many different tasks depending on which parts are added to them. For example, you can add blades to make a fan out of a wheel or add sticks to make a cart with wheels out of an axle. Also, gears can be used instead of or along with other machines to create motors or pumps.