What Is a Lever?
A lever is a tool that uses the principle of leverage, consisting of a fulcrum, a force point, and an action point. A single fulcrum and a bar are all that is needed to use it as a lever.
There are many tools in the world that use the lever principle. A typical example is a nail puller. A crowbar used for lifting and shifting heavy objects is also a type of lever.
Scissors and pliers also use the lever principle and can be considered as types of levers.
Uses of a Lever
Levers are used to amplify and utilize the force applied. For example, it would be very difficult to remove a nail from a piece of wood with only the force of a finger. However, with a nail puller, the nail can be pulled out in an instant by the lever principle.
They are also used to carry heavy objects. Wooden sticks were used as levers when the pyramids were built in ancient Egypt. Other times, they are used for cutting, such as with scissors or nippers.
How to Select a Lever
There are many ways to use levers. Here we introduce the shapes and names of leverage tools according to their uses, so you can refer to them when selecting a tool.
- Pulling
This is the simplest lever and is often rod-shaped. It has a fulcrum in the middle and force and action points on both sides.
･Nail puller
･Crowbar - Lifting and Carrying
As with the puller, there are many simple shapes. There are force points and action points on both sides with a fulcrum in between.
･Crowbar
･Drum lifter
･Carrier - Gripping
Two arms are used to grip and hold an object. The two arms intersect at the fulcrum, with the handle as the force point and the gripping part as the action point. There are also types like tweezers that have a fulcrum at one end, a point of action at the other end, and a force point in between.
･Pliers
･Tweezers
･Tongs - Cutting
The principle is the same as the gripping tool, but the point of action is the blade. Two arms intersect with the fulcrum as the intersection point, with the handle as the force point and the cutting portion as the point of action. Also a type with a fulcrum at one end, an action point at the other end, and a force point in between, like a thread cutter.
･Nippers
･Scissors
･Thread cutter