Glossary of Terms

Acrylonitrile-butadiene-styrene plastics are used extensively in the molding of vacuum cleaner cases and trim parts. It is an economical plastic which is lightweight but strong and resists stains and chemicals. See also our article on External Structure Materials & Durability

Charcoal from which most of the impurities have been removed. It is made by treating ordinary charcoal with steam and air heated to above 600 degrees Fahrenheit. It is the best adsorbent since its many empty spaces give it a large internal surface to hold particles.

The process of moving in a rapid and violent manner. Carpet is usually agitated by the brushes and sometimes a beater bar on the revolving brush roll in a vacuum cleaner. See also our article on the Effects of Brushing Action.

The movement of air from one location to another. In a vacuum cleaner, it generally refers to the movement of air through the vacuum cleaner or central vacuum system and is measured in cubic feet per minute (C.F.M.). It is one of the most important aspects of vacuum cleaner performance. Air flow in a vacuum cleaner is inversely proportional to the total resistance within the system and directly proportional to the suction created by the suction motor. For additional information, see our article on Air Flow through the System.

The pressure of atmospheric or compressed air. At sea level, atmospheric pressure is 1,013.2 millibars or 14.69 pounds per square inch. A vacuum cleaner's suction motor reduces the air pressure in order to create air flow. See also our article on Fan or Impeller Types & Performance.

A specification developed in an effort to rate the output power of the vacuum cleaner instead of its input power. It is based on suction with air flow as measured at the vacuum cleaner inlet. See also our article on the Power of the Suction Motor.

The strength of an electric current flowing through a wire or other electrical conductor expressed in amperes (amps). One ampere of current will flow through a conductor having one ohm of resistance when a potential of one volt is applied to it. Vacuum cleaners are often rated by the amount of amperage drawn from the electrical outlet which flows through them. The maximum permitted for UL Approval is 12 Amps. See also our article on the Power of the Suction Motor.

Available current in a battery is typically rated in Amp Hours. This is the amount of amps the battery can supply for one hour. Smaller batteries may be rated in milli-amp hours (mAh), a milli-amp being 1/1000 of an amp.

An armature is made of a laminated steel core which is wound with copper enamel-insulated wire. The windings are attached to a copper commutator near one end of the armature. It can be considered the heart of a motor since it is the armature's rotation, motivated by electrically created magnetic fields within the motor, that converts electrical energy into mechanical energy. See also our article on the Suction Motor Design & Operation.

Bakelite is an important thermosetting resin made from phenol and formaldehyde which can be injection molded to make parts which are resistant to heat, chemicals and moisture. See also our article on External Structure Materials & Durability.

A low friction type of bearing in which round steel balls rotate between a spinning inner race (small steel ring with a rounded grove on it's outer surface) and a stationary outer race (larger steel ring with a rounded grove on it's inner surface). The sides often have shield or seal rings to retain the grease and keep the bearing as clean as possible.

A long rigid bar or raised area on a revolving brush roll which pushes the carpet away from the roll, creating a rapid beating action. Stiff bristles on a brush roll can have a similar effect.

The rapid hitting action caused by a beater bar or stiff bristles on a brush roll. The effect of this is to help work the dirt and grit toward the top of the carpet.

The brush roll is the part of a vacuum cleaner which contains rows of bristles and sometimes beater bars to agitate the carpet in order to significantly aid in the removal of dirt from it. While often being in the shape of a cylinder, some are contoured, being more like an auger in appearance. It is mounted in the nozzle by its ends and contains bearings which allow it to be rotated at a high speed by the brush motor or turbine. Most vacuum cleaners use the same motor to create the suction and rotate the brush roll.

The act of brushing a carpet's fibers, often by a revolving brush roll. This is a significant part of the agitation process performed by an upright or power nozzle, effectively removing dirt from the carpets.

A type of motor cooling design which incorporates a separate air flow through the motor to cool it. The main air flow, which picks up the dirt, travels through the suction fan or fans but bypasses the motor itself. This prevents residual dirt or moisture in the main air flow from coming in contact with the armature, field, carbon brushes, etc. Bypass cooling is always incorporated in wet/dry vacuum cleaners as well as the traditional "dirty air" uprights. A motor is either a bypass cooled type or a flow through (FlowThru) cooled type.

Represents Cubic Feet per Minute. The specification typically used to indicate the amount of air flow which will pass through a clean vacuum cleaner power unit when running by itself. When rating the main power unit of a central vacuum system, it is normally measured at the 2" opening where the 2" piping will be attached. See also Air Flow.

The type of vacuum cleaner that houses the suction motor and filtering system in a somewhat square or rectangular container. Typically incorporating a "clean-air" system, they are known for producing strong suction for use with the attachments. When a power nozzle is part of the system it is often referred to as a "power team." A canister type vacuum cleaner usually contains wheels which allow it to be pulled after the user by its hose. See also our article on the Standard Canister type.

A vacuum cleaner design in which the air flow which picks up the dirt is cleaned by the filtering system before it passes through the fan or fans of the suction motor. This design eliminates fan breakage problems which can be caused when objects are picked up by a dirty-air system. Also, it typically produces significantly more suction, especially when a hose and attachments are used. See also our articles on Fan or Impeller Types & Performance and the "Clean-Air" Upright type of vacuum cleaner.

There are two different ways of viewing cleaning effectiveness. The most common use has to do with the ability of a vacuum cleaner to pick up dirt from the surface being cleaned. The other has to do with the ability of the filtering system to clean the air so a minimum amount of dirt and allergens is recirculated back into the home.

A cog belt is made of reinforced rubber with cogs similar to teeth on a gear along the inner surface. These provide a positive power transfer between the motor and brush roll for the full life of the belt. Unlike stretch type belts, cog belts can not stretch nor slip so they perform well for many years.

A commutator is the part of an armature which has individual bars of copper which are positioned in the shape of a drum. The motor brushes are held against the commutator in order to carry the electrical current to the armature windings which are connected to it.

Electrically speaking, the flow of electrical charges through a wire or conductor. Usually rated as amperage (amps).

Relative to filtration systems, cyclonic systems separate the dust particles from the air flow by spinning the air within a separation chamber. The spinning causes centrifugal force to act upon the dust particles, moving them outward while the air exits from the inner part of the chamber. Some cleaners use multiple chambers and most cleaners add filters to increase the total system filtration efficiency.

A vacuum cleaner design in which the air flow which picked up the dirt passes directly through the fan of the suction motor and into the bag. While usually not producing as much suction for use with attachments, this design often will produce more air flow when working with large openings and short air flow distances. This is another name for a system using the Dirty-Air or traditional upright design.

On many newer power nozzles and uprights, the brush roll is designed so that its bristles reach fairly close to the edges of the nozzle to enable brushing very close to the carpet's edges. Dual edge brushing (both sides) can be obtained by running the belt either in the center of the roll or a few inches from one end instead of at the very end of the roll.

A special type of vacuum cleaner hose which has internal wires which carry the electrical current which runs the power nozzle's motor. Often these same wires are used to reinforce the hose but not always as in the case of crushresistant hoses.

A type of filter media consisting of very fine synthetic fibers on which a static electric charge builds as air passes through them. This charge attracts even the smallest of dust and allergen particles, aiding the filter in retaining them. See also our article on Filtration Efficiency - HEPA, Micron, etc.

The fan or impeller is the disk shaped structure with fins that creates the actual suction in a vacuum cleaner. For more information, see our article on Fan or Impeller Types & Performance.

Relative to a vacuum cleaner motor, the field consists of a laminated iron frame on which one or two coils of copper wire are wound. It is shaped so that it wraps around the core of the armature on two opposite sides. The flow of electrical current through the coils creates a magnetic field which interacts with the magnetic fields created by the coils on the armature to cause the armature to rotate. For more information, see our article on Suction Motor Design & Operation.

The percentage of particles retained by the filter as air passing through it. The size of the particles is typically specified since the filtering efficiency increases as particle size increases. See also our article on Filtration Efficiency - HEPA, Micron, etc.

The system through which air passes to have particles removed from it. It typically consists of a series of filters made from various filter media. Various components which can be used in filtering systems include paper bags, nylon electrostatic filters, glass fiber paper filters, cloth or foam filters, cyclonic chambers, and even water. See also our article on Filtration Efficiency - HEPA, Micron, etc.

The suction motor design where the air flow which picked up the dirt travels through both the suction fans and the actual motor itself to cool it. This type of motor can only be used in vacuum cleaners which incorporate the "clean air" design so that very little residual dust is present in the main air flow.

When used relative to supplies or parts, this term indicates that the item was manufactured or marketed by the same company that manufactured the product in which it is used. This manufacturer is often called the Original Equipment Manufacturer (OEM). See Genuine vs. Generic Dustbags for the importance of using dustbags marketed by the OEM.

A filtering system wherein each filter in the series of filters is designed to remove particles which are smaller then the previous filter. This enhances air flow and extends the filter media's effective life span. See also our article on Filtration Efficiency - HEPA, Micron, etc.

A type of filter or paper bag which uses similar construction or fibers to that used in a true HEPA filter. Some are thick filter pads which actually meet the stringent HEPA filtration specification. While being a significant improvement over regular filters, the vacuum that uses it may not have a completely sealed filtration system so there is no guarantee that the stringent HEPA specification will be met by it. Manufacturers who use Certified HEPA filters tend to consider any non-certified HEPA filter to be a "HEPA Type" filter. See also our article on Filtration Efficiency - HEPA, Micron, etc.

The tendency of matter to remain stationary if not moving or to keep moving in the same direction if not stationary. Inertia is what causes the air in a fan to move outward as it spins since it tries to move in a straight line.

Lexan is GE's registered trademark for a particular polycarbonate resin. For more information, see our article on External Structure Materials & Durability or General Electric's articles on GE Plastics and Designing with LEXAN Resin.

Relative to a vacuum cleaner, the object (mass) or device to which the power of the electric motor or turbine is delivered. The forces applied by the power of the brush motor or turbine enable the brush roll to revolve, its brushes and beater bars moving the carpet fibers. The forces applied by the power of the suction motor enable the fans to spin, moving the air that is entering them. For more information, see The Load to the Suction Motor in our article on Suction Motor Design & Operation.

The area near a current-carrying conductor or a magnetic object in which the forces due to the magnetic object or current can be detected. The strength of magnetic fields are increased by wrapping the conductor (typically an enamel insulated wire) around a soft iron object. This is done in the construction of the armatures and fields used in vacuum cleaner motors.

A unit of measure equal to 1/1,000,000 meter (10^-6 meter). To put this into perspective, the diameter of a human hair is typically 80 to 100 micrometers. According to the National Institute of Standards and Technology (formerly known as the National Bureau of Standards) as stated in their Metric Style Guide this term should be used instead of the obsolete term micron.

A unit of measure equal to 1/1,000,000 meter (about 1/25,000 inch). To put this into perspective, the diameter of a human hair is typically 80 to 100 microns. While this term is often used for specifying particle sizes for the HEPA and ULPA filtration specifications, it is actually considered obsolete by the National Institute of Standards and Technology (formerly known as the National Bureau of Standards) as stated in their Metric Style Guide. The more proper term for this unit of measure is micrometer (µm).

This type of filter gets its name from its ability to trap micron (micrometer) size particles at a very high efficiency rate. Its filter media consists of very fine synthetic fibers on which a static electric charge builds as air passes through them. This charge attracts even the smallest of dust and allergen particles, aiding the filter in retaining them. See also our article on Filtration Efficiency - HEPA, Micron, etc.

A unit of measurement typically used in the USA to report atmospheric pressure. A newer term for millibars used by US scientists and the rest of the world is hectopascals (hPa). You may see the suction of a European vacuum cleaner rated in millibars. To convert from millibars to inches of mercury, multiply it by 0.02953. Since mercury has a specific gravity of 13.546, you then need to multiply the inches of mercury by 13.546 to get inches of water lift. Alternately, you can simply multiply millibars by 0.4 to get inches of water lift.

In a vacuum cleaner motor, the motor brushes are carbon rods which are held against the commutator in order to carry the electrical current to the windings on the armature. They are often called "carbon brushes" as well. See also our article on Suction Motor Design & Operation.

Nylon is one of the toughest, strongest and most elastic substances. The discovery of nylon in 1935 by Wallace H. Carothers, while working at the E. I. du Pont de Nemours & Company (now Du Pont), is considered one of the most important chemical discoveries in history. See also our article on External Structure Materials & Durability.

When used relative to supplies or parts, this acronym means "Original Equipment Manufacturer" and indicates that the item was manufactured or marketed by the same company that manufactured the product in which it is used. When this is true, the product is often said to be "Genuine." See Genuine vs. Generic Dustbags for the importance of using dustbags marketed by the OEM.

The paper bag in a vacuum cleaner consists of an special paper enclosure into which the dirt and air are directed as part of the filtering system. The paper used is specially processed to permit the air to pass through it while retaining as much of the dust and dirt as possible. See also our article on Efficiency of Paper Bags.

An exaggerated rating of the output of a vacuum cleaner suction motor measuring the horse power using the formula which is based on torque per second. See also Peak Horse Power in our article on the Power of the Suction Motor.

An extremely tough and strong synthetic plastic with the ability to maintain its shape and size even under great stresses over a wide range of temperatures. It is an ideal engineering plastic since it can be injection molded, blow molded, or extruded. See also our article on External Structure Materials & Durability

The process by which small molecules called monomers are linked to form giant long-chain molecules called polymers. For more information, see our article on External Structure Materials & Durability.

Polystyrene is an ideal injection molding plastic which is hard, extremely transparent and a good insulator. It was first marketed by the Dow Chemical Company in 1937. See also our article on External Structure Materials & Durability.

Relative to vacuum cleaners, the physical or mechanical force or energy that is applied to the load. Typically the electrical power is transferred from the household electrical outlet to the electric motor where it is converted to mechanical power. The mechanical power is then transferred to the load of the brush roll or fan. When a turbine is used to drive a brush roll, it actually removes the power it applies from the air flow, reducing the velocity of the air flowing through the system. See also our article on the Power of the Suction Motor.

A special attachment for deep cleaning carpets. It incorporates a revolving brush roll similar to that used in the upright type of vacuum cleaner and an electric motor to drive it. When using a power nozzle, the electric motor actually adds power to the cleaning system. A power nozzle should not be confused with a turbine nozzle. When a turbine is used instead of an electric motor, the power to drive the brush roll is actually removed from the air flow, reducing the velocity of the air flow through the system.

The type of vacuum cleaner that teams a canister type vacuum cleaner with a motorized power nozzle. The powerful brushing action of the power nozzle, combined with the strong suction of the clean-air suction motor, enables a power team to perform very well deep cleaning carpets as well as cleaning all other types of surfaces. For examples of excellent power teams, see our list of Ristenbatt Vacuum's Preferred Models. See also our article on the Two-Motor Power Team type of vacuum cleaner.

The suction measured when there is no air flow through the suction motor. This is done by completely blocking the inlet of the motor or vacuum cleaner with the gauge. It is a measure of the potential developed when the motor is running at its maximum speed. Resistance to air flow within a system does not affect this measurement. For more information, see The Load to the Suction Motor in our article on Suction Motor Design & Operation and our article on the Power of the Suction Motor.

Used broadly, the ability of a vacuum cleaner to efficiently pick up dirt. When used in a more narrow way, it is the actual pull or pressure difference created by the spinning fans in the suction motor. The term suction is often used interchangeably with the term vacuum. Air flow in a vacuum cleaner is inversely proportional to the total resistance within the system and directly proportional to the suction created by the suction motor. See also our article on Fan or Impeller Types & Performance.

The motor in a vacuum cleaner which drives the fans to create the suction. The fans and fan casings are usually installed by the manufacturer and considered an integral part of the suction motor. See also our articles on Suction Motor Design & Operation, Fan or Impeller Types & Performance and the Power of the Suction Motor.

A force that produces or tends to produce rotation on an axis. In an electric motor this is the force from the interaction of the magnetic fields produced by the flow of current through the armature and field coils. See also our articles on Suction Motor Design & Operation.

A vacuum cleaner design in which the air flow which picked up the dirt passes through the fan of the suction motor before it is cleaned by the filtering system. This designation is used since most uprights used this design since their inception. While usually not producing as much suction for use with attachments, this design often will produce more air flow when working with large openings and short air flow distances. Therefore, this design in an upright usually performs well when cleaning carpets. This type of system is also referred to as a Dirty-Air Design. See also our articles on Fan or Impeller Types & Performance and the Traditional Upright type of vacuum cleaner.

A special attachment for deep cleaning carpets. It incorporates a revolving brush roll similar to that used in the upright type of vacuum cleaner and an air driven turbine to drive it. A turbine nozzle should not be confused with a motorized power nozzle. When a turbine is used instead of an electric motor, the power to drive the brush roll is actually removed from the air flow, reducing the velocity of the air flow through the system. When using a power nozzle, the electric motor actually adds power to the cleaning system.

A type of vacuum cleaner which is self-contained and has a handle extending vertically from its main case. Typically it contains a revolving brush roll for deep cleaning carpets. Many uprights also have on-board attachments for cleaning furniture and hard-to-reach corners although the suction with them usually isn't as strong as with the canister types. Being self-contained, uprights are pushed around in front of their users, eliminating the need to pull something behind them. For examples of excellent uprights, see our list of Ristenbatt Vacuum's Preferred Models.

A total vacuum is the absence of everything, even air. Vacuum cleaners actually create a partial vacuum, or more accurately, an area of reduced air pressure as air moves outward within the fan. Air flow is created as air with normal air pressure moves toward the area with the reduced air pressure. See also our article on Fan or Impeller Types & Performance.

The speed of the air at any specific location in the vacuum cleaner system. It is the force exerted by the moving air which actually picks up the dirt and moves it into the bag or dirt container.

Polyvinyl chloride, typically called vinyl or PVC, is a very versatile thermoplastic material. It is strong, easily colored and resists abrasion. It can be produced in a very soft form or a rigid form where it has one of the highest combinations of stiffness and impact strength. See also our article on External Structure Materials & Durability.

Electric potential or potential difference, expressed in volts. It is the push and pull of the potential difference between two points which causes electrical current to flow through a wire or device which is connected across them. The voltage in a typical household electrical outlet ranges from 103 to 120 volts.

Relative to vacuum cleaners, water lift is a measurement of the strength of the vacuum produced by the suction motor. Suction gauges used on vacuum cleaners are calibrated in "Inches of Water Lift". This is equivalent to taking a vertical tube, placing the bottom in a container of water, attaching the vacuum cleaner hose at the top and measuring how high above the water surface the water in the tube rises. By the way, one cubic inch of water weighs 0.036 pounds so the negative pressure in pounds per square inch can be found by multiplying the water lift by 0.036. If you see suction rated in millibars (mbar), multiply that number by 0.4 to convert it to inches of water lift.

A watt is a unit of measurement of electrical power equal to the rate of work performed by a current of one ampere produced by a potential of one volt. Also, one horsepower (actual, not peak horsepower) equals 746 watts. To find the power of vacuum cleaner motor in watts, simply multiply the amperage rating by the normal household voltage rating of 103 to 120 volts. See also our article on the Power of the Suction Motor.