How Does a Leaf Blower Work?
When the fall season rolls around and the leaves start to drop from the trees, it becomes harder to keep your lawn and pathways in order. A leaf blower can make for a far quicker clean-up job than simply using a manual rake or broom.
If you're deciding which type of leaf blower to buy, or if you've just bought one and are wondering how to use it, learning how a leaf blower works will help you in your gardening endeavors.
In order to truly understand how a leaf blower works, it is important to understand its different parts and the role they play. Here’s a look at all the parts of a leaf blower and what they do:
Providing the power
The motor in a leaf blower powers the impeller, which produces the air pressure used to clear the leaves. There are two primary types of motors in leaf blowers: gasoline engines and electric motors. It’s significant to understand the differences between both types, so you know how a leaf blower works and which one is better for your needs.
Gasoline Powered Leaf Blower
Gasoline-powered leaf blowers use a combination of gasoline and oil, to power a motor that produces the air pressure needed to clear leaves. They are bulkier and heavier machines than electric blowers, but they can offer more power (in some cases a lot more power). They are available in many different sizes & price ranges, but are generally heavy duty machines capable of clearing away a lot of leaves and garden waste.
Electric Leaf Blowers
Electric leaf blowers are lighter and more compact than gas models. They use an electric motor to power the impeller that creates air pressure. The principle is the same but the motor is generally less powerful, and the leaf blower is lighter and cheaper than a gasoline-powered leaf blower. They come with either a cable connection or rechargeable versions that use battery power to make the motor function.
Turning the motor's power into moving air
The next component to help you understand how a leaf blower works is the impeller. The impeller (basically another name for fan) provides the air pressure, which is used to push away the leaves. This fan is powered by the motor, and it is housed within the leaf blower near the motor itself. It is a spinning rotor, consisting of blades that rotate at high speeds to produce the necessary air pressure.
The larger the fan, and the faster it turns, the more air your leaf blower will be able to push out.
ereplacementparts.com has some details on leaf blower impellers.
Where the air comes from
The outlet nozzle is where all the air produced by the fan comes out. This outlet directs the air into a focused path, so that you have a proper direction to work with. The outlet nozzle plays an important role and comes in different lengths and shapes, which can be useful for different applications. Some leaf blowers come with additional nozzles to provide more focused power for when you need it.
The nozzle is an important aspect to consider when you want to know how a leaf blower works.
Cubic Feet Per Minute (CFM) & Miles Per Hour (MPH)
The combination of motor power, impeller design, and outlet nozzle design dictates how much air the leaf blower will move. Manufacturers usually quote 2 figures - CFM and MPH.
Leaf blowers are available with air volumes from under 90CFM (cubic feet per minute) to over 500CFM; more is usually better. Air speeds are generally from just over 100MPH, to well over 200MPH.
Be aware that the manufacturers play games with these figures - if they supply a small nozzle with the blower & rate the air speed with this nozzle attached, the air speed through the small nozzle will be high, but the blower will not be able to move much air at this speed.
When choosing a leaf blower, it's best to look at both the CFM and MPH, and don't choose a model just because 1 of the 2 figures sounds impressively high, as another choice with lower MPH but higher CFM may be better. It's the combination of CFM and MPH that makes for an efficient tool.
Powering cordless leaf blowers
Electric-powered leaf blowers come in two further sub-types. There are mains-powered blowers, that need a constant connection to an electrical socket, and then there are the more portable battery-powered blowers. Rechargeable batteries allow cordless electric leaf blowers to function without the limitations of a cable. The main downside is that they cannot function for too long because battery will run out after a while, needing to be charged again before you can resume using the tool.
Most cordless leaf blowers available today are powered by lithium-ion batteries, which are much more powerful than the older lead-acid batteries. What this means is you get both longer life between charges (most modern blowers last for at least 30 minutes before recharging), and lighter weight, so you don't get tired so soon.