Edger
Encyclopedia
An edger is a garden tool
used to cleanly separate a lawn
from a walkway
or other paved surface, such as a concrete sidewalk
or asphalt path
. Edgers may be manual or automated, typically employing a small two-stroke gasoline motor or an electric motor
. Use of an edger defines a clear separation between the lawn and the walkway, imparting a finished appearance that is neater than can be achieved by merely mowing over the border of the lawn and walkway (which frequently permits tufts of low-growing grass to hang over onto the walkway, resulting in an irregular or ragged appearance).
In operation, a manual edger usually includes a broad hemispherical blade attached to an elongated handle, which the operator uses to drive the blade into the turf directly alongside the hard surface. In addition, the blade may have a flat top to allow the operator to step on the blade, driving it deep into the lawn and turf in order to clear a space between the lawn and the hard surface. In contrast, powered edgers may operate on any of a variety of methods, such as rotating wheel blades or thrashing wheels, which also operate to define a clear separation between a lawn and a hard surface.
A basic gasoline lawn edger consists of an engine, belt
tensioner
, pulley
s, and a blade
. Most lawn edgers incorporate a belt and two pulleys (one on the engine and the other on the blade head) and a belt tensioner used for going deeper into the grass and gaining more RPM
. Some gasoline edgers also have a device called a "robot head," used for adjusting the pitch of an edger head between the horizontal and the vertical. Some edger brands, such as King O' Lawn, have a blade clutch
to avoid the user pulling up on the belt tensioner to stop the blade (usually a small lever that can be pulled up with the operator's foot). The drive system on a common edger is a belt drive from the two pulleys. Husqvarna
uses a worm gear shaft drive system. One disadvantage to the shaft drive system is lower engine power. A chain drive would be ineffective and cause damage to the blade, sprocket, and engine if a solid object was hit. One advantage to the belt drive system is that the belt will skip when hitting objects. The blade on an edger is usually made from cast steel.
1.5 horsepower (1.1 kW) engine. Using just basic components, the first edgers were very basic with a very small engine. Brands such as McLane and Cooper Klipper would follow several years later.
engine with 2 or 3.5 horsepower
(1.5 or 3 kW), although some early edgers used a 1.75 horsepower (1.3 kW) engine. Some modern gasoline edgers use engines ranging from 3.5 to 4 horsepower (2.5 to 3 kW), and some economy edgers use a two-stroke
engine.
Cordless and corded electric edgers are also available in a range of motor power levels.
Garden tool
A garden tool is any one of many tools made for gardens and gardening and overlaps with the range of tools made for agriculture and horticulture...
used to cleanly separate a lawn
Lawn
A lawn is an area of aesthetic and recreational land planted with grasses or other durable plants, which usually are maintained at a low and consistent height. Low ornamental meadows in natural landscaping styles are a contemporary option of a lawn...
from a walkway
Walkway
In US English, a walkway is a composite or umbrella term for all engineered surfaces or structures which support the use of trails. These include sidewalks, footbridges, stiles, stairs, ramps, paseos or tunnels...
or other paved surface, such as a concrete sidewalk
Sidewalk
A sidewalk, or pavement, footpath, footway, and sometimes platform, is a path along the side of a road. A sidewalk may accommodate moderate changes in grade and is normally separated from the vehicular section by a curb...
or asphalt path
Path
Path, pathway or PATH may refer to:-Path:* Course , the intended path of a vehicle over the surface of the Earth* Trail, hiking trail, footpath, or bridle path...
. Edgers may be manual or automated, typically employing a small two-stroke gasoline motor or an electric motor
Electric motor
An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...
. Use of an edger defines a clear separation between the lawn and the walkway, imparting a finished appearance that is neater than can be achieved by merely mowing over the border of the lawn and walkway (which frequently permits tufts of low-growing grass to hang over onto the walkway, resulting in an irregular or ragged appearance).
In operation, a manual edger usually includes a broad hemispherical blade attached to an elongated handle, which the operator uses to drive the blade into the turf directly alongside the hard surface. In addition, the blade may have a flat top to allow the operator to step on the blade, driving it deep into the lawn and turf in order to clear a space between the lawn and the hard surface. In contrast, powered edgers may operate on any of a variety of methods, such as rotating wheel blades or thrashing wheels, which also operate to define a clear separation between a lawn and a hard surface.
A basic gasoline lawn edger consists of an engine, belt
Belt (mechanical)
A belt is a loop of flexible material used to link two or more rotating shafts mechanically. Belts may be used as a source of motion, to transmit power efficiently, or to track relative movement. Belts are looped over pulleys. In a two pulley system, the belt can either drive the pulleys in the...
tensioner
Tensioner
A tensioner is a device that applies a force to an object to maintain it in tension. Often the amount of force is adjustable. There are tensioners for applying a tensioning force to drive belts and chains, fibers, and bolts....
, pulley
Pulley
A pulley, also called a sheave or a drum, is a mechanism composed of a wheel on an axle or shaft that may have a groove between two flanges around its circumference. A rope, cable, belt, or chain usually runs over the wheel and inside the groove, if present...
s, and a blade
Blade
A blade is that portion of a tool, weapon, or machine with a cutting edge and/or a pointed tip that is designed to cut and/or puncture, stab, slash, chop, slice, thrust, or scrape animate or inanimate surfaces or materials...
. Most lawn edgers incorporate a belt and two pulleys (one on the engine and the other on the blade head) and a belt tensioner used for going deeper into the grass and gaining more RPM
Revolutions per minute
Revolutions per minute is a measure of the frequency of a rotation. It annotates the number of full rotations completed in one minute around a fixed axis...
. Some gasoline edgers also have a device called a "robot head," used for adjusting the pitch of an edger head between the horizontal and the vertical. Some edger brands, such as King O' Lawn, have a blade clutch
Clutch
A clutch is a mechanical device which provides for the transmission of power from one component to another...
to avoid the user pulling up on the belt tensioner to stop the blade (usually a small lever that can be pulled up with the operator's foot). The drive system on a common edger is a belt drive from the two pulleys. Husqvarna
Husqvarna AB
The Husqvarna Group is the world's largest producer of outdoor power products including chainsaws, trimmers, lawn mowers and garden tractors. The Group is also the European leader in consumer watering products and one of the world leaders in cutting equipment and diamond tools for the construction...
uses a worm gear shaft drive system. One disadvantage to the shaft drive system is lower engine power. A chain drive would be ineffective and cause damage to the blade, sprocket, and engine if a solid object was hit. One advantage to the belt drive system is that the belt will skip when hitting objects. The blade on an edger is usually made from cast steel.
History
The gasoline lawn edger was invented by Louis Faas Sr. of King o' Lawn Inc in the 1940s. The first gasoline edgers used a Briggs & StrattonBriggs & Stratton
Briggs & Stratton is the world's largest manufacturer of air-cooled gasoline engines primarily for outdoor power equipment. Current production averages 11 million engines per year.-History:...
1.5 horsepower (1.1 kW) engine. Using just basic components, the first edgers were very basic with a very small engine. Brands such as McLane and Cooper Klipper would follow several years later.
Power sources
Most gasoline edgers use a four-strokeFour-stroke cycle
A four-stroke engine, also known as four-cycle, is an internal combustion engine in which the piston completes four separate strokes—intake, compression, power, and exhaust—during two separate revolutions of the engine's crankshaft, and one single thermodynamic cycle.There are two...
engine with 2 or 3.5 horsepower
Horsepower
Horsepower is the name of several units of measurement of power. The most common definitions equal between 735.5 and 750 watts.Horsepower was originally defined to compare the output of steam engines with the power of draft horses in continuous operation. The unit was widely adopted to measure the...
(1.5 or 3 kW), although some early edgers used a 1.75 horsepower (1.3 kW) engine. Some modern gasoline edgers use engines ranging from 3.5 to 4 horsepower (2.5 to 3 kW), and some economy edgers use a two-stroke
Two-stroke cycle
A two-stroke engine is an internal combustion engine that completes the process cycle in one revolution of the crankshaft...
engine.
Cordless and corded electric edgers are also available in a range of motor power levels.