Innovative components and consumer demand for fuel efficiency, quality and comfort

When considering buying a new car, consumers have a checklist of qualities and features with which the ideal must comply. It has to have the right look and price, but what consumers also want from their cars is comfort and a trouble-free experience.

For a number of consumers, the automobile must offer a smooth driving experience, with no jolts from the road. Most desire a noise-free ride with an engine that purrs like a kitten, rather than roaring like a lion, along with an interior that is plush and cosy; a home away from home. If automotive manufacturers meet these vital criteria, consumers will come back to their brand time and time again. 

Automotive manufacturers, however, have a checklist of their own that must be ticked off when developing a new car model. Top of their agenda is meeting stringent targets for carbon dioxide (CO2) emissions reduction, such as those introduced by the US Environmental Protection Agency (EPA), obliging automotive manufacturers to lower tailpipe emissions to 101 grams per kilometre by model year 2025. European Commission regulations in effect since 2012 now impose fines of 20 Euro on every car manufacturer for every gram of CO2 emitted over the limit of 130 grams per kilometre for every car across their entire fleet. This fine is due to rise to 95 Euro for every gram per kilometre by 2015. In China, steps are also under way to impose tighter carbon emissions regulations with the introduction of its National Standard IV, based on guidelines currently in place in Europe, in the next 12 months. To achieve this reduction in CO2 emissions, manufacturers are looking for ways to minimise the fuel consumption of their cars by optimising engine efficiency and lightweighting mechanisms throughout the vehicle. Above all, they must meet all of these criteria while keeping manufacturing costs in control.

In automobile manufacturing, even the smallest parts can make a big difference in making sure the automobile ticks every box on the checklists of both consumers and automotive manufacturers. Innovative technology, such as tolerance rings and composite bearings, can help by providing consistent controlled friction levels over the lifetime of the mechanisms in which they are used to optimise engine function. They can ensure a smooth, quiet ride to enhance the quality of the interior fittings for consumers and enhance fuel efficiency for automotive manufacturers.

Steering Drivers toward Satisfaction

When looking to improve the overall driving experience, the steering system is the logical place to start. By removing looseness from the steering system and ensuring consistent friction levels over its lifetime, automotive manufacturers can improve customers’ perception of quality. 

To offers consumers the smooth, comfortable feel they demand, automotive manufacturers need to minimise excess vibration in the steering column from the road and the engine cost-effectively. They can do so by mounting the bearing within the steering column with a tolerance ring. These solutions are radially sprung steel frictional fasteners that allow for a stiff interference fit between the steering column’s mating components. By increasing stiffness of the joint, tolerance rings effectively absorb vibration from the road surface and surrounding mechanisms and prevent its transmission to the vehicle interior. This minimises the unpleasant feel of quivering while steering for motorists. 

To further improve steering feel and response, car makers can turn to composite bearings in the yoke application. Used between the steering rack and pinion gear, composite bearings act as a cushion. Their unique polytetrafluoroethylene (PTFE) liner dampens vibration to facilitate smooth, consistent steering and enhance the mechanism’s long life.

Composite bearings in steering applications also help automotive manufacturers comply with CO2 emission reduction regulations. They are lighter than alternatives such as metal and rolling-element bearings, contributing to weight savings. By utilising innovative components such as composite bearings, automotive manufacturers can enhance the smart design of their cars and create new fuel-efficient models. For example, composite bearings can be customised for applications and manufactured with lightweight materials notably stainless steel or aluminium backing, while allowing for higher loads. Composite bearings enable car manufacturers to implement light housing materials, such as aluminium or magnesium, further enhancing the automobiles’ lightweight design properties. In addition, the improved load and stress resistance capabilities of composite bearings, with specialised materials such as polygon structured bronze layers, allow for smaller and slimmer housings for mechanisms.

A Relaxing Ride

To give consumers a smooth, comfortable and quiet drive, it is critical to prevent vibration from powertrain mechanisms from reaching the passenger area. The dual mass flywheel dampens torsional vibrations from the engine to stop them from being transmitted to the gearbox, resulting in a quieter drive even at a lower number of revolutions per minute (RPM), which can exaggerate the judder from the pistons firing. The composite bearing allows for the smooth movement of the flywheel around the shaft.  Its PTFE liner’s thickness and internal structure absorbs noise, vibration and harshness (NVH) for a noise-free environment for the driver and passengers.

Smoothing it Over

The unique properties of composite bearings ensure consistently low friction levels over the life of the vehicle, and allow them to be unaffected by excessive heat or other external factors. This offers smooth movement in applications such as the seat frame, contributing to a high-quality feel and customer satisfaction. 

Depending on individual customer specifications, the seats can be configured with up to eleven different adjustments in manual or power versions. While adjusting a seat, consumers are looking for smooth movement with minimum effort. To isolate metal-to-metal contact in these adjustments and to prevent associated noise and friction, automotive manufacturers utilise sliding bearings, be they Dry Universal (DU), plastic injection mould or composite bearings. Although most new car seats might offer the same quality feel, plastic and DU bearings wear out with time, resulting in the metal-to-metal contact that causes rattling noise and a rigid feel. Moreover, plastic can act differently in low temperature conditions, making seat adjustment more difficult in winter time, for instance. 

By utilising composite bearings, automotive manufacturers can guarantee consistent performance of adjusting mechanisms over the long life of the vehicle.  Composite bearings’ PTFE liner offers constant controlled friction for correct adjustment operation. It allows the pivot to move smoothly, while its filler compounds enhance wear resistance so performance does not degrade over time. The PTFE liner also acts as a cushion between the pin and the housing, compensating for thermal expansion of mating materials and enabling the consistent mechanism performance that is perceived as high quality. 

To enhance interior quality, automotive manufacturers need to prevent seat armrests from falling down during movement. The protrusions of the tolerance rings and their unique sprung-ring shape ensure the perfect fit between two mating parts. The tolerance ring used at the pivot acts as a simple clutch mechanism, maintaining the appropriate torque when the armrest is stowed, while controlled friction ensures a quality feel and consumer perception of performance. 

Rust is never a good sign on a car. The use of composite bearing with a self-lubricating, corrosion-resistant liner of PTFE and special filler compounds ensures weatherability, protecting door hinges from undesirable corrosion and ensure long-term customer satisfaction. 

Long-lasting, Happy Customers 

The consistently controlled friction and NVH reduction offered by innovative composite bearings and tolerance rings can significantly enhance the consumer driving experience throughout the lifetime of the car, which can be the deciding factor for the next purchasing decision or recommendation. These next generation solutions also allow automotive manufacturers to meet governmental regulations for reduced CO2 emissions and improve fuel efficiency.  

By Saint-Gobain