Continental New Wheel Concept

New Wheel Concept is a conceptual technological solution to the brake system for electric vehicles.

On July 26, 2017, technology company Continental AG announced the expansion of the list of solutions for electric vehicles, creating the New Wheel Concept for the specific features of these cars.

The wheel rim of an electric vehicle consists of two aluminum parts: an internal aluminum carrier star with an aluminum brake disk and an external aluminum rim bottom with a tire. Unlike conventional wheel brakes, the New Wheel Concept uses an aluminum disc from the inside. This makes it possible to use a particularly large disk diameter, which has a positive effect on the braking characteristics.

To increase the range of an electric car without recharging, when slowing down, it generates as much electricity as possible through recovery (braking by an electric motor), so the wheel brake is used less often. The corrosion-free aluminum brake disc also prevents the formation of rust (as is common on cast iron discs), which can impair the braking effect.

Electric transport needs new technologies in the field of braking. In this case, the use of conventional brakes is not very effective. On the other hand, the New Wheel Concept meets all the requirements for an electric car brake. We used our experience in brake systems to develop a solution that provides a consistently reliable braking effect in an electric vehicle. Matthias Matic, Head of Hydraulic Braking at Continental

The New Wheel Concept reduces the weight of the wheel and brakes, making the design of the electric car easier. The advantages of the concept are the simplified replacement of wheels and brake pads, in the absence of disc wear.

The New Wheel Concept is based on the design of the section between the wheel and the axle. The wheel consists of two parts: an aluminum bearing star, which is bolted to the wheel hub, and the bottom of the rim is attached to the star. The wheel brake is attached to the wheel holder on the axle and engages from the inside with an annular aluminum brake disk, which, in turn, is bolted to the bearing star. The internal brake allows the use of a wide friction radius of the brake disc, since the space available in the wheel is used optimally. During the development, the braking characteristics of the New Wheel Concept were designed for mid-range and compact cars. In accordance with today's requirements for such parts, the brake is characterized by strength and meets all established criteria, although it is much less often used in electric vehicles.

In an electric car, it is very important to use as little energy as possible on a mechanical brake. During deceleration, the inertia of the car is converted by the generator into electricity to increase the range without recharging. Therefore, the driver continues to use the brake pedal, but this does not mean that the wheel brakes are also used. " The torque of the electric motor during deceleration becomes insufficient in the case of more vigorous braking, and braking must also take place on the non-driving axis for reasons of dynamics. A wheel brake is necessary in this situation and it must be accessible. Drivers want to be sure that braking is possible at any time, and a large amount of rust on the brake disc can prevent this. The reason for the deterioration in braking performance lies in the less friction of the brake shoe and the disc. For automatic emergency braking, a mechanical brake must also be fully available. Paul Linhoff, Head of Brake Pre-Development, Chassis and Safety Division, Continental

The design of the New Wheel Concept took advantage of the light aluminum material for the brake. Due to the effect of the lever on the large brake disc, a fairly low pressing force is sufficient to provide a high level of braking efficiency, and since aluminum has a very high thermal conductivity, the heat generated by the disc during braking is rapidly dissipated.

According to the results of practical tests, the company concluded that the aluminum disk itself is not subject to wear, unlike cast-iron disks. Through the New Wheel Concept, abrasion occurs only on the pads, and the design of the system makes their replacement (and wheel replacement) easier.

Since the brake disc is fixed from the outside and the brake is gripped from the inside, the brake caliper can be made particularly light and rigid. The force is transmitted for the most part symmetrically to the center of the axis, which has a favorable effect on the brake noise level. And it's a side effect that's particularly appealing in a quiet electric car. Paul Linhoff