Vacuum Cleaner Belts and Performance
Vacuum Cleaner Belts come in many styles and hundreds of sizes.
Typically, domestic vacuums use a belt to drive an agitation device - also called brush roller. With only a few exceptions, most vacuums use either a flat belt, a round belt (O-RING style) or a geared belt (also called toothed / notched belt).
The Type of belt your vacuum uses is very important, not only for durability's sake - but also performance. The type and condition of belt your vacuum uses will have a major impact on the systems ability to clean carpeted surfaces. Proper agitation (Beating, sweeping and brushing carpet fibers) is nearly 70 percent of a vacuums cleaning ability.
You can also read that as less than 30% of vacuumed soil (on a carpeted surface) is removed by suction.
Suction is very important however,. It is suction that pulls the dirt that has been beaten or brushed from the carpet into the vacuums collection media (paper bag or dust cup). Suction (airflow) is also the key factor in cleaning hard surfaces or when using the vacuums hose with attachments. Without suction a vacuum cleaner could only bring dirt to a carpets surface. While obviously both suction and agitation are important in vacuuming carpets, it is the agitation that actually cleans them.
Most all manufacturers use a brush roller made of wood, metal or plastic driven by a suction or brush motor through the use of one of the three kinds of belt - Round, Flat or Geared.
Round belts are the earliest style of belt as they were simple to produce and easy to engineer on a vacuum. Unfortunately the round style of vacuum belt is generally run in the same space as vacuumed dirt. This means nearly all the dirt, paper clips, staples and hair you vacuum pass around the belt - cutting, nicking or scratching the belt along the way. These belt also had to stretch a longer distance, placing more stress on the brush roller and the motor bearings. This type of belt is still in use today on some domestic commercial vacuums. The average useful life of these belts can be sometimes measured in minuets of use in commercial applications. For home use, most vacuum can go 3 or 4 months before the noticeable reduction of cleaning ability as the belt begins to stretch and slip.
As belts moved from a natural rubber compound to more synthetic ingredients they became a little more durable, but more importantly they could be manufactured in styles other than "round". Enter the flat belt, perhaps the most common belt in use on domestic vacuums today. The flat belt is circular as all other belts but have a flat face. This is important because the point of contact could be expanded from 3/16" on a round belt up to 5/8" or even 3/4" on a flat belt. I guess you could say that "there is more rubber where it meets the road". More contact mean less slippage, however the vacuums fault tolerance is still built in.
What is vacuum belt fault tolerance? - The rubber belt runs on an extended motor rotor shaft designed to hold a belt in place up to the brush roller. The belt is stretched into place for normal use and requires stored tension in the rubber belt to operate. If the vacuum is used and put into a condition where the brush can not turn the belt is designed to burn, then break. While this is a pain to anyone cleaning on Sunday before company comes over, it is a necessary evil. If the belt did not stretch, burn then break then it could possible be the motor that would try to stretch, burn then break. Just imagine that every time you caught the corner of a throw rug, or vacuumed up the kids socks you had to replace the motor in your vacuum. So this fault tolerance, while a bit low-tech, does work.
Flat belts are also most often run in a circular fashion as well, instead of the twisted route the round belt takes to deliver performance in the proper direction. This allows the manufacturers to run the belt off one side of the brush roller, instead of the center where the dirt is. This is a great innovation as well because you can eliminate premature failure due to dirt and soil in the belt path, and you also move the belt close to the brush roller bearing reducing stress on the entire machine.
Flat belts were defiantly an improvement to vacuums in general, and continued to be improved themselves. One company has introduced a Kevlar© vacuum belt. As you might imagine, this belt does not stretch but is tensioned by an external pulley. The hope is that this belt will have an extended life of 8 to 12 months. Also recently, Hoover has combined flat belts with another style of ridged belt called a "V" belt. The "V" belt is used to drive the roller because it is hard and not subject to cuts and scratches in the brush roller chamber. The flat belt is used farther back in the chain protected from the dirt to provide tension, extending its life 2-3 times that of normal flat belts.
The last design of belt is considered by us in the industry as the best. While many variations exist, the geared belt is the most efficient method by which to drive a brush. The geared belt is also called a positive drive system because the energy of the brush motor is transmitted directly to the brush. The brush and motor are locked by fixed teeth to each other trough a tensionless cogged belt. This direct connection results in higher cleaning efficiency because the brush can be driven at a faster speed regardless the age of the belt. Flat belts stretch as they become used (and warm) losing their tension. This can mean a vacuum with a worn tension belt will clean 40% - 80% less effectively than a vacuum with a new belt. Your vacuums belt is always stretching - losing it's tension from the moment you put it on even wile at rest stored in the closet.
Geared belts are not used under tension. You do not stretch a Geared belt into its place. Geared belts are also usually reinforced, made of neoprene and fiberglass just like those in a car. Geared belts are also many times more durable than flat or round belts. Reinforced geared belts will typically last years under normal household use, and in many cases will last the life of the machine - never needing replacement.
There is really only one drawback to geared belts; the initial cost of the vacuum.
Geared belts are usually used on two motor vacuums, either canister powerteams or European two motor uprights such as Lindhaus or Windsor. Not only is a separate suction and brush motor required, but also electronic sensory systems to tell the user when something is wrong in the brush. These new electronic sensors take the place of the old burning belt, stopping the system in an instant when something other than dirt and dust is accidentally pulled into the nozzle. Imagine that, instead of driving all over town Sunday looking for the right vacuum belt, you simply pull juniors toy soldier out of the vacuums brush, and start cleaning again.
As you can see, belts are very important to your home vacuuming efforts, and the technology behind vacuum belts is still changing. The newest advances in belt technology are clutched brush systems with gearing reduction allowing the use of a geared belt on single motor vacuums, and even the new "beltless" vacuums that have actually embedded a motor into the brush roller - eliminating the need for a belt completely. Always keep a fresh vacuum belt on hand, or upgrade to a geared belt system and your time will be better spent while you vacuum.