August 17, 1915 NEW YORK, NEW YORK

Now wait a minute, let's check that date again. Yes in August of 1915 patent #1,150,148 was granted to Mr. W.H. Putnum of New York for his new and unique anti-skid device. (See copy) As you can tell from the attached drawings, Mr. Putnum was clearly into something that could be quite beneficial to many vehicle operators yet, Mr. Putnum never got the mission accomplished. It wasn't until the winter of 1977 that Mr. Goren Torneback, of Linkoping, Sweden, a small town 150 KM south of Stockholm, brought Putnum's idea to fruition by mounting an automatic tire chain system onto a local milk delivery truck.


1978 - Swedish inventor Goren Torneback brings his original Automatic Tire Chain to North America following his European success with the product called Instachain. Mr. Torneback attempts to trademark the Instachain name. Unfortunately a company in Toronto, Canada has a product that is trademarked "Instant Chain" and Mr. Torneback's application is denied. He changes his product's name to Onspot, which means instant in Swedish. The rest is history.

View original Instachain brochure





The system permanently fastens to the rear suspension of the vehicle. The driver can activate a dashboard switch that opens an electric over air solenoid mounted on the frame rail. Air pressure from the vehicle's on board are brake system or an auxiliary air source flows to two air cylinders that lower two chainwheels down until they contact the tire sidewall. The friction between the tire and the chainwheel causes the chainwheel to rotate. Each chainwheel has 6 lengths of chain attached to it. The centrifugal force created causes the chains to flail out and pass between the tire and road surface to enhance traction in snow and ice in forward or reverse. The additional traction also reduces stopping distance in these same slippery conditions. When the switch is turned off, the solenoid exhausts the air in the cylinder and the spring in the cylinder returns the chains to the resting position. (See line diagram)


Automatic tire chains can provide two major advantages to the user:
  1. Increased safety. At the vehicle is always equipped, the driver has access to chains at a moments notice. Typical engagement time is two seconds. If the driver suddenly finds himself on black ice, a simple flip of the switch ca get the vehicle under control and could conceivably avoid an accident.
  2. Productivity gains. If the operator is constantly getting out of the vehicle to put on and remove chains, automatic chains can dramatically reduce this task. Clearly, this is a time savings yielding increased vehicle and driver productivity. More importantly, the vehicle can stay on schedule. Added to this is the elimination of body damage caused by broken conventional chains, which at times can also be a mission disabling failure. Advantages in hauling force, acceleration and stopping distance are dramatic.


Automatic chains may give a driver the sense of false security. The driver must realize that this system is not a fix all. The system must still be turned on. The system is designed to work on ice, packed snow, and up to 6 inches of snow. Automatic chains are ineffective in 15 inches of snow, so the driver may have to resort to installing conventional snow chains in deep snow conditions.


Automatic chains were originally designed to fit large vehicles with air brakes as the system requires a compressed air source to operate it. Many smaller vehicles without air brakes have been fit with the use of a 12-volt electric air compressor and holding tank. As a general rule of thumb, automatic chains can be adapted to MOST vehicles from ˝ ton pickup trucks to large tractor-trailers. The determining application factor is the ground clearance and the number of chassis related obstructions such as fuel tanks, exhaust pipes and sway bars. If you are considering the purchase of automatic tire chains, you should contact the manufacturer for the required application information. Typically you will need to have the vehicle's rear suspension measured and potential obstructions noted. A word to the wise: an automatic tire chains system is NOT a one size fits all type of product. Take the 15 minutes of time and get the vehicle you want to fit measured.


Research shows that volunteer fire departments are the biggest users of automatic chains. They must always be prepared yet are unable to get people to install and remove conventional chains at all hours of the day and night. Moreover, a broken conventional chain could result in a missed fire call and a $2500 wheel well repair. The second largest users are school bus operators. Here, safety is paramount. Other users of automatic chains include plow trucks, utility companies and tractor-trailer operators who operate in chain control areas. Yes, automatic chains are approved as a single set of conventional chains in those states that have chain control areas.


Generally speaking, an automatic tire chain system can be installed on a large truck with air brakes for under $2000. A smaller vehicle without air brakes is typically MORE expensive, as the operator must purchase the auxiliary air compressor kit and have it installed along with the chain system. Smaller vehicles without air brakes have an installed cost in the $2200 range.


An automatic tire chain system requires very little maintenance, as there are few moving parts. Typically there are one or two grease fittings that can be looked after during normal vehicle maintenance. The chainwheels should be removed in the summer months to prolong the life of the arm bearings. This procedure would take a shop technician about 10 minutes of time to remove and 10 minutes to reinstall the chainwheels. Replacement parts are readily available with the most common replacement part being the chains themselves. Replacement chainplates are typically $90 per side. Overall, the system is categorized as "low maintenance" with few spare parts required. By the way, if you wish to trade in a vehicle with automatic chains and transfer the system to the new vehicle a minimum of new rear axle mounting brackets is required. If the new vehicle is similar to the old one, i.e. both have spring suspension with air brakes; typically a new set of mounting brackets is all that is required for the swap.


Are automatic tire chains new? NO. Numbers show that well over 100,000 systems have been installed on all types of vehicles. Are automatic tire chains the answer to all winter situations? NO. As previously stated. ALL products have their limitations. Feedback from automatic chain users indicates that this system addresses 90% - 95% of their traction needs. The clear advantage is the convenience of having chains available without having to stop or get out of the vehicle. As the chains are only used when needed, chain life is far greater than conventional chains. The vehicle is never operated on a dry road with chains on, so vehicle and road damage are non-existent. Each potential buyer of automatic chains must examine their own operation and determine HOW and IF automatic chains can improve their vehicle and driver productivity and safety.

Onspot of North America is a member of:

  • Independent Armored Car Operators Association
  • Supplier Council to the National Association State
  • Directors Pupil Transportation Services
  • New York State Association of Fire Chiefs
  • National Association of Emergency Vehicle Technicians
  • American Public Works Association