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Summary

ICOS™ reduces dimensions
Developing new technology to increase chain saw performance is a high priority for Husqvarna, as is decreasing weight. For one new model now in development and testing, in–house engineers wanted to slim down the saw’s body even further.
“We try to compress everything to make the saw as small and light as possible,” says Per Carlbäck, project leader at Husqvarna’s Research and Development department.
Normally, two components are needed when making the crankshaft bearing and seal arrangement – deep groove ball bearing and a separate radial shaft oil seal – resulting in a total width for bearing and seal of approximately 16.5 mm. To save space, Husqvarna used ICOS, an Integrated Compact Oil–Sealed bearing unit from SKF, which combines the seal and the bearing, bringing the width down to 13 mm.
Besides offering a width savings of 3.5 mm, which is good news for Husqvarna, the ICOS solution (patent pending) has other benefits as well. According to its inventor Asbjörn Bundgart, business manager for bearing seals within SKF’s seal division, the ICOS unit reduces mounting errors, it can cut the number of suppliers from two to one, and
it reduces or eliminates contamination risk during installation. The ICOS standard range comes in two designs of 11 sizes for the 62 series of bearings, and in two different rubber materials for a wide range of applications.
The ICOS standard range is an alternative to standard bearing/seal arrangements. The concept also provides an opportunity for tailoring a low–cost, oil–sealed bearing unit. “We are now making just a seal and combining it with a standard bearing,” says Bundgart. “The synergies between bearings and seals are very big, but they have yet to be explored. Husqvarna has great potential for using ICOS, because of the added value it gives to their applications.”
SKF has supplied ball bearings to Husqvarna since 1959, when its chain saws first went into production. The usual arrangement is two standard deep groove ball bearings (either 6202 or 6203) on each side of the wrought–iron crankshaft of a chain saw’s motor. Ball bearings can also be found in the gearboxes of Husqvarna’s grass trimmers.

Not many companies boast a 310–year history, but Husqvarna, a maker of outdoor power tools, has been a recognised name since 1689.Following the Biblical injunction to beat swords into ploughshares, Husqvarna has survived more than three centuries by first producing guns, then sewing machines, bicycles, motorcycles, stoves, dishwashers, washing machines, outboard motors, refrigerators and chain saws. Part of the Outdoor Products division of Electrolux since 1978, Sweden’s Husqvarna is today a specialist supplier of outdoor equipment for forestry and park professionals.
While Husqvarna–branded motorcycles are still competing on the motor–racing circuits, they are now made by Italy’s Cagiva group, which licenses the name. The same goes for Husqvarna sewing machines, produced by Sweden’s Industrikapital, an investment group. Domestic appliances are still sold under the name Husqvarna, but actually made by parent company Electrolux.
The company’s production of guns dwindled during the 1700s. Nevertheless, the company retains its 300–year– old logo, a cross–section of a gun barrel with a sight.

Husky business
Still young at heart, Husqvarna today has its niche in the forest and garden sector, for which it manufactures chain saws, grass trimmers, lawn mowers and accessories. The company employs 1,800 people and exports 95 percent of its products to 16,000 retailers in more than 80 countries.
“Every second chain saw in the world is made by Electrolux, which includes the Husqvarna, Jonsered, Partner, Poulan and McCulloch brands,” says Pär Martinsson, project manager at Husqvarna’s Research and Development department.
Husqvarna, which means “mill house” in Swedish, still spells its name the old–fashioned way, with a “q,” though the town where the company is located now uses a more modern spelling. Huskvarna has a population of 20,000, and most likely got its name for its location near a waterfall on a river flowing into Lake Vättern, Sweden’s second–biggest lake. The falls powered early sawmills and industrial workshops.
North American loggers, one of Husqvarna’s most important market segments, know the company as “Husky,” and have even been known to wear Husky tattoos to show their allegiance to the brand.

Eye to eye with a robot
At first sight, the company’s sprawling production facility fits well with the company’s illustrious past. But enter any of the turn–of–the–century brick buildings on the Husqvarna site, and you’re likely to be met by a robot or an unmanned truck moving products through the assembly process.
“We have a lot of advanced robots so our brain power can be used for better things,” says Jan Henriksson, director of the plant’s high–pressure die–casting shop. This foundry produces, among other components, the aluminium cylinders used to power Husqvarna’s more than two dozen models of chain saws. A robotic arm then drills holes where the spark plugs will fit.
There is a lot more to a chain saw than meets the eye. Production began in 1959, when an outboard motor was hooked up to power a drive shaft and a sword–like instrument. That year, 359 “Alaska” models left the factory. The tool quickly caught on among forestry workers, and improvements were later made to reduce the machine’s noise, vibration and weight.

Ergonomic luxuries
Forty years later, Husqvarna chain saws have all the refinements of a four–wheel–drive luxury car. Using CAD (computer–assisted design) tools, the company builds robust and ergonomic machines for use by professionals and casual users alike.
“The safety and ergonomics of chain saws, and keeping their weight and size to a minimum, are our guiding lights,” says Per Carlbäck, project leader at Husqvarna’s Research and Development department. “Professional loggers, for example, often have to carry them deep into the forest. Weight is a critical factor.”
Like the suspension system in a well–appointed car, most Husqvarna chain saws are equipped with a vibration–damping system that insulates the handle from the engine unit. Most have air injection systems to protect the engine and reduce the need to clean the air filter, as well as an inertia–activated safety chain brake that can stop the saw in less than 0.15 seconds. Some versions are even equipped with heated handles for use in cold climates.
“We keep a batch of Husqvarna saws in our cabin,” says logger Stig Dahlberg, speaking from a mobile phone in the woods of northern Sweden. While Dahlberg’s crew of four uses highly automated tractor–like grapple harvesters to fell trees, the chain saws come in handy in hard–to–reach areas. “A chain saw is a must up here, and Husqvarna is a big, well–known brand. In addition, we’re close to servicing and parts.”
The company’s various chain saws are differentiated by the size of their engines. The smallest saw weighs 3.4 kilograms and has a 35–cc engine, while the biggest has a motorcycle–sized 120–cc engine and weighs just over 10 kilograms. For environmental reasons, some chain saws are equipped with catalytic converters.

Lower emissions
Husqvarna’s commitment to developing environmentally friendly products has led to other innovations as well. The company no longer uses cadmium in its plastics and paints. A few years ago, it developed Vegoil, a non–toxic biodegradable chain grease based on rapeseed oil. Another innovation is Aspen, Husqvarna’s new “green” chain saw fuel, which contains no benzene, alcohol or ethers and is very low in sulphur and aromatic hydrocarbons.
“Cutting chain saw emissions is a big issue for us right now,” says Martinsson. “Many of our customers still take our tools deep in the woods, far away from civilisation. But increasingly, landscapers and park professionals use chain saws closer and closer to towns. And we want to prevent too much disturbance.”

Alexander Farnsworth
a feature writer based in Stockholm
photos Husqvarna

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