Street Sweeper – The Science Behind The Technology

I’m sure by now you are aware that the common street sweeper has been around for a long time. What you may not be aware of is that there is more technology to these rather noisy machines than most people think.The science behind the water, the brush, and the technology may surprise you!

All of these elements combined in the modern street sweeper help keep neighborhoods clean, improve the environment, and keep people healthy. Here’s a few surprises that many people do not know about today’s modern street sweeping.

Street Sweeper – One of the First Vehicles on the Road

Sweepers were one of the first mechanical vehicles to appear in cities and residential neighborhoods. The very first street sweeping machine was patented in 1849 by its inventor C. S. Bishop.

Motor-driven street sweepers actually started appearing in the streets of Boise Idaho in 1914. This was the Elgin motorized street sweeper built by the Elgin Sweeper Company headed up by Mr. D. M. Todd.

Sweeping Science Fact 1

Many people think that the water sprayed by a street sweeper is for cleaning…It’s not.

The water sprayed by a street sweeper is actually a technique to keep dust on the road while the cleaning bristles sweep debris into the hopper. Spraying water on the street is required by environmental laws to keep dust from fouling the air and contaminating the environment. If you see a street sweeper kicking up a lot of dust, then the water jets are either clogged or the water tank on the sweeper is depleted.

Sweeping Science Fact 2

There are several types of brushes on a street sweeper and they act as a mechanical brooms. These brushes are:

Tube brushes – that have bristles attached throughout the tubes or strips of bristles attached in rows. The bristles are made of either steel, polycarbonate or a combination of both.

Gutter brushes – are shaped like a flat disk and rotate to push curb debris to the tube brushes. The tube brushes then “sweep” the debris onto a conveyor belt which drops it into a collection hopper.

Sweeping Science Fact 3

Debris (trash, leaves, branches, etc) from the sweeping is collected in a storage bin called the hopper.

Storage hopper’s come in all different sizes and need to be emptied regularly to avoid jamming the conveyor belt and damaging the mechanical components of the sweeper. Here’s a photo that shows a standard street sweeper emptying their hopper:

Evolving Technology for Sweepers