Are your bearings causing you problems?

• Insecure mounting
• Need a minimum footprint
• Assembly difficulties
• Excessive Wear
• Misalignment
• You want minimal maintenance

We have the answer!

For children who are unable to pedal a conventional bicycle a company decided to develop a new cycle but to do this had to overcome some engineering problems. Unlike a traditional bicycle this innovative three-wheeled bike had to eliminate the difficult circular pedalling motion, replacing it with a more natural up and down stepping action.

The answer was to change this to be more like walking than cycling to give the forward motion. But of course a bike needs more than just special pedals, it also requires suitable handlebars, steering, and control. To tackle these issues the engineers realised they had to change their thinking and let the riders design the cycles. In addition the designers also involved physical therapists who suggested tilting the steering column back towards the rider so that children with spinabifida would be able to fit the cycle.

The first problem to deal with was the design of the steering column, which used a flange nylon bearing, located on a pin welded to the front axle. This caused major problems as it had no self-aligning feature and would just fracture when the steering column was tilted.

The engineers searched for suitable bearings and Spyraflo provided the answer. They requested samples of the oil-impregnated bronze self-clinching, self-aligning bearing that offers a ±5° self-alignment capability. The oil-impregnated bronze bearing was chosen for its rugged construction, as well as the self-lubricating feature as this would also keep the carbon steel alignment pin from corroding.

With the new bearing in place, the steering column could then be positioned where the rider needs the handlebars without inhibiting rotation of the column. Probably most children will not use the full 5° self-aligning feature but in tests it was used to its maximum and the steering column still worked flawlessly.

The engineers also had the added benefit in terms of cost saving and simplicity of assembly due to the patented self-clinching feature of the Spyraflo bearing. As the bearing is pressed into the bore, the tapered sides force material up into an undercut below the flange. The serration’s of the bearing act as multiple cutting edges that increase the flow of material into the undercut. When finished, the flange of the bearing is flush with the surface, and becomes an integral part of the assembly.

Micromech is the UK and Eire distributor of these clever bearings, if you would like more information about them, then contact Alan Spinks on 01376 333333 or alan@micromech.co.uk

‘A revolution in Bearings’