Screws are a simple machine that are very useful in many cases. A screw is a cylindrical object that has a spiral thread and is most often visualized as the metal screw that is used to secure wood, plastic, and electronics.
But screws do a lot more than just that! Screws convert motion, but in this case, it has a mecahnical advantage by changing circular turning motion into linear forward/backward motion.
Screws are used not only to hold things together, but to drill holes in things and to pump liquids. Some good examples of screws are bolts, screws, bottle caps, guitar tuners, light bulb, tap, and cork openers.
What is a Screw?
Simply, a screw is an inclined plane wrapped around a cylinder. Think of it as a cylinder with a head (solid top) at one end and a pointed tip (similar to a nail) at the other end, for the most part. Most importantly, it has ridges that wind around it. The technical term for these ridges (or grooves) around the shaft or cylinder is threads.
The distance between threads is constant for each screw, but different on other screws. The distance between threads is called a Pitch.
Screws have uses for holding things together, pulls or pushes an object together. Screws can be used to lift heavy items and can also tighten things too.
Nail and Screw
They may look alike, but they are different. The nail does not have threads around the shaft like the screw does.
Driving a screw into a piece of wood is more difficult because the ridges of the screw create a lot of friction and resistance turning with the screwdriver. When you drive the screw into the wood it has to turn in a circular motion with the screwdriver.
Related Post:
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- 35 Different Types of Screws and Their Uses
- What is the Difference Between Bolt and Screw?
- 30 Different Types of Screw Heads and Their Uses
- Types of Fasteners (Screws, Rivets, and Washers)
Screw Simple Machine Examples
Common examples of screws include:
- Screw pump
- Bulb
- Jar Lid
- Drill Machine
- Bolt
- Bottle Caps
- Faucets
- Car Jack
- Wine Corkscrew
- Gas Tank Cap
- Screws
- Guitar tuners
- Light Bulb
- Ball Point Pens
- Circular Stairways
#1. Screw Pump.
As the name indicates, a screw pump is an example of a screw simple machine. A screw can be used to pump water from a lower elevation to a higher elevation. The machine uses a number of screws to use the positive displacement theory to move fluid along.
While we commonly refer to this as an Archimedes’ Screw since it’s credited after him, there is evidence of a screw pump being used for irrigation prior to Archimedes’ birth.
Related Post: What is Screw Pump? | How Do Screw Pump Work?
2. Bulb
In order to make a bulb stay in the holder, a sufficient twisting force is applied to it. The twisting force allows the bulb to rotate. The thread cuttings on the bottom of the bulb and the inside of the holder fit together perfectly, so this is one of the prime examples of a simple screw machine.
3. Jar Lid
The threads on the neck of the jar match those on the jar lid, closing a jar by matching the threads of the lid to the jar.
To do this, a torsion force is applied to the lid to close the jar. If the force is applied in the opposite direction, then the lid will open the jar that is closed. This mechanism acts like screw, which is a simple machine.
4. Drill Machine
A drill machine is a very fast and very strong electric machine that makes holes in a surface. The drill also has a rotation to allow cutting metal with threaded points to make rough holes smooth and easy to drill into walls or wood.
This works when electric power is applied and the work has been completed. A drill machince is also an example of a simple screw machine.
5. Bolt
A bolt is one of the many basic examples of a simple screw machine. A bolt is used to hold two objects together, along with a washer and a nut. The bolt has thread cuttings around its entire length that match the thread on the inside of the nut.
6. Bottle Caps
These days, we tend to think of machines as consisting of a complex mechanical arrangement of objects and overlook the existence of machines that we use in our daily lives. For example, adding and removing the bottle cap on a bottle requires all the functions of a simple screw machine.
7. Faucets
Faucets, the devices used for controlling the flow of water (or any other fluid), are another typology of simple screw machines.
To increase the flow of water flowing from a faucet, it is turned in the clockwise direction or the inverse direction, which is made possible by the action of a screw machine.
8. Car Jack
A screw jack is a type of engineered device that allows a user to convert rotational motion into a linear motion. A screw jack or worm screw utilizes the threads of its structure to either push or pull an object depending on the direction in which it is turned.
Car jacks tend to be small or portable devices, but a car jack can hold the weight of an automobile, which makes it one of the most important examples of screw machines.
9. Wine Corkscrew
A corkscrew is a simple metal screw attached to the base of a piece of wood. If someone uses a wine corkscrew to open a bottle of wine, they can grip the arrangement firmly while they apply torsional force until the screw is tightly anchored in the cork.
They can easily extract the cork with a vertical pull. Therefore, the wine corkscrew is an excellent example of simple screw machines.
10. Gas Tank Cap
We often neglect to think about some devices that we use on a daily basis as simple machines. Here’s an example: gas tank cap. In order to affix the gas tank cap on the top of a fuel tank, a torsion force is applied to it that allows it to function as a simple screw machine.
11. Screws
Have you noticed your wood piece is affixed to your wall through the small pointed piece of fastener that holds your frame piece or painting to your house wall?
It is this simple machine that is a screw, another cool home example of a simple machine.
The screw looks like a bolt, but the differences are in the length and diameter and point that is protruding from the end of the screw. The circular spiral threads are exactly like the bolt.
12. Guitar Tuners
Have you looked at the guitars closely to see it has some knobs upside?
These knobs are called Guitar tuners and they are used to tune the guitar according to the guitar player requirements or preferences.
Because these knobs or taps are able to screw or loosen the strings, and how the knobs work are an excellent example of a screw. These knobs have spiral threads that allow a player to lose or tighten the screw according to their needs.
13. Light Bulb
Have you unscrewed a bulb from its holder or socket at your home? If yes, then you might see that you are rotating your hand to secure the light bulbs so light up other parts of your home. This twist and turn by the threads located on the light bulb is another great home example of a screw.
14. Ball Point Pens
You have used a ball pen to scribble down something or a list, or notes on a piece of paper. But, have you noticed those caps at the top or centre of the pen to refill the ink when of gets dry?
If yes, then this ball point pen is another awesome demonstration of a screw simple machine. The pen cap has spiral circular threads to tighten or loosen the cap when necessary.
15. Spiral Stairways
A staircase that has a spiral shape from bottom to top, attached to a long column, is known as a spiral staircase or circular staircase. The purpose of these spiral stairs is to fit into the minimal amount of space. But you might ask how these spiral stairs are examples of screws?
So here is your answer:
As you noticed, those stairs create similar spiral thread shapes as you have seen in the previous examples. These circular stairs are also an excellent example of an inclined plane, as you might notice the angle of inclination.