Snow chains

Snow chains are an aid for vehicles on snowy roads and muddy terrain, they are mounted on the tire. A distinction is made between full-fledged snow chains and starting aids.

Full-fledged snow chains form a network that is pulled over the treads of the tires. According to the arrangement of the chains further distinction by drive chains and trace chains.

Drive chains prevent the wheels from spinning. They are mounted on the wheels of the drive axle (s). The chain pieces are intended to prevent the slipping of the wheels are transverse to the running surface.

Track chains are mounted on the wheels, the steering axle (s) and give the wheels a longitudinal guide to prevent lateral slipping. Here run the main chain pieces in the running direction.

Today, most chains used on car or truck are a combination of drive and track chains. The chain pieces criss-cross across the tread and are always connected with longitudinal pieces. Pure drive chains are mainly used on construction machinery or tractors in forest management for timber extraction.

The chain links are made of hardened steel, plastic, textiles or other materials. They are usually polygonal, to provide a better frictional resistance. Often even loose round chain links available that will continuously release the rolling chain of adhering snow.

Use

There are different views as to whether chains tightened or loosened to fix. While loose chains have a better self-cleaning capacity, damage taut chains, the surface of the tire less. As in the wheel arches is usually very little space, the chain is rather curious mounted.

Before applying the chain is to consider whether there is sufficient space in the wheel arches. Not all vehicles allow the assembly of chains on snow tires standard size. This can lead to damage to metal parts or semi-axes.

In simple models, the chain is laid out in the longitudinal direction from the respective tire. Then a piece of the chain must be run in order to then place them around your tires and to be able to relate the two ends. The installation is troublesome for beginners. Therefore, the chain manufacturers try to simplify the process. In such chains, a spring-loaded steel ring is mounted over the tires, and then you drive a few inches to be related also the outside of the chain. After installation, some meters are to drive and take up slack in the chain tension again.

For vehicles with ESP or ASR Snow chains can not be fully effective under certain circumstances. The driving aids prevent a strong wheelspin and thus the " digging in" of the chains into the ground. It may therefore be useful to deactivate depending on the vehicle ESP / ASR or raise their intervention thresholds.

The maximum permissible speed for driving with chains is regulated in many countries. Thus, the rate in Germany is limited by § 3 IV Highway Code at 50 km / h as well as in Switzerland and in the Czech Republic. In Austria it is not regulated. In general, however, been obtained by the engine noise and the bumpy driving, that you do not go too fast. The usually driven with chains speed is a maximum of 40 to 50 km / h

Types

Starting aids

Starting aids are used to overcome difficulties when starting. They are only suitable for short distances ( leaving a property, etc.) can be claimed which drove without chains. For cars are mounted on the wheels as traction only brackets.

In more rare encountered case of motorcycles uA come special start-up claws or belts are used.

Spin chains

Spin chains ( technical term actually rotating chain) are traction equipment for vehicles on icy or snowy roads. They consist of chains which are attached to the lower end of vertically disposed shafts. These shafts are mounted in the vicinity of the drive wheels. In adverse conditions, they are driven in rotation, so that the chains are accelerated in a circular path by rotation of the shaft. Thus they are thrown again before the wheels. Then the wheel rolls on the chains, resulted as snow chains higher friction and traction. The rotor axis of the chains is executed to rotate by about 45 ° towards the front of the car. The directions of rotation of the left and right side of the vehicle must be opposed. When reversing the direction of rotation must be reversed. This is achieved normally by the fact that the spin chains are driven directly from the (drive) wheels - in principle as a dynamo.

The advantage of spin chains is that they can be from the driver's seat and off mostly. Thus they are quickly ready for use and off just as quickly. Thus, the tendency of the driver to use this traction increases. But spin chains do not replace the prescribed traffic by strings.

Spin chains are mainly used in heavy commercial vehicles.

With a legislated duty chain only full chains may be used.

Motorcycle Tyres

A rather rare find use snow chains on motorcycles. Especially in the ( stable ) sidecar are snow chains in winter but popular tool to build up the desired traction.

Due to the relatively low penetration of snow chains for motorcycles are often made in the Self. But there are also a few scattered manufacturer of motorcycle chains, such as Hubert Staudacher.

Snow grippers

A special form of tracked vehicles in the military sector are mainly snow grippers. Your metal crawlers are usually equipped with slick rubber pads. However, on slippery surfaces (ice, hard-packed snow) they offer little traction. Therefore, some of the rubber pad can be replaced by metal gripper. The snow grippers are usually mounted externally on the vehicle in the unused condition in one or more rows.

Time of use, and legal regulations

Trucks or buses that are traveling in the transport of the relevant regions are generally fitted with snow chains. More difficult is the situation in the long-distance transport, since the vehicles often cause no chains with it and then either bypasses or waiting times have to accept until a track is clear for traffic again. Vehicles that need to be quickly ready for use, such as fire engines stand in the cold season, mostly with landscaped chains in the garage because the chains taken off faster than can be placed.

On motorways have prior sections, of which there are a chain of obligation into consideration so -called chain berths be provided. An example is the Vienna outer ring road, which can be very often driven especially in the early morning hours after a snowfall only with chains.

History

Snow chains are an invention by the American Harry D. Weed, the U.S. Patent Office on August 23, 1904 issued a patent certificate.