AUTONEWS

ZF presents a seat belt that heats and increases range

Car manufacturers know that optional equipment is what attracts customers the most, and also brings good profits. Heated seats are one example, but ZF experts believe that this is an outdated system. They have found a more efficient, although perhaps cheaper solution.

Heated seats are standard on most cars sold in Scandinavia. With the advent of electric cars, the optional function of heated rear seats also appeared - which has begun to spread among a good number of brands, especially Asian ones.

Usually available only for the front, they have recently been offered on the rear seats, although not on all, but only on the outer ones, i.e. on the seats closer to the doors. This is an interesting feature that ZF experts studied in detail and concluded that it consumes a significant amount of energy, so they further improved their previous system.

As Autonews reports, this solution is not designed just to be a cheaper option than heated seats, at least not at first glance, because these are full-fledged heated seat belts. ZF Lifetec emphasizes that these seat belts complement existing heating systems and provide a comfortable temperature for the upper body.

Namely, the heated seat belt is only 1.3 millimeters thick and contains four thin cable heaters long enough to cover the pelvis and chest of the driver or front passenger. These heaters, which are capable of generating a maximum heat output of 60 W, can reach temperatures of up to 40°C in less than two minutes.

The system has an algorithm that calculates the optimal heat output based on body temperature (approximately 37ºC) and skin temperature (32 to 34ºC), external and internal temperatures and solar radiation recorded by vehicle sensors, in addition to data from the automatic climate control system.

The advantage of the new ZF heated seat belt is twofold: the temperature is adjusted automatically, without user intervention, and its effectiveness has also been proven in electric cars. Energy consumption is minimal and can therefore increase the range of electric cars by up to 6 percent.

ZF calculations indicate significant energy savings for interior heating, up to 1000 W on short trips, when the warm-up phase is the most important and requires the air conditioning to operate at full power to achieve a comfortable temperature in the passenger compartment in a maximum of 10 minutes.

This technology allows drivers to reduce the energy used to heat the vehicle, especially in combination with other contact heaters, such as a seat heater. During cold weather, the system can increase driving range by up to 15% by reducing the energy required to heat the vehicle interior. The ZF heated seat belt is based on a special webbing with integrated heating conductors that minimally increase the belt's thickness. This makes integration easier for automakers and offers occupants the same comfort as a standard seat belt. The heated belt is designed to provide occupants with a uniform sensation of warmth close to the body.

With this integrated heating function, ZF's new heated seat belt can provide heat close to the body immediately after the driver starts driving, typically between 36 and 40 degrees Celsius. Combined with heated seats, the heated seat belt has the potential to quickly provide occupant comfort. In electric vehicles, the climate control system is powered by battery power, as there is no usable waste heat like in a combustion engine. Reducing the amount of battery current used to heat the vehicle interior can allow for a range gain of up to 15% by using contact heaters and reducing the use of conventional climate control systems.

Other advantages of the ZF heated seat belt are crucial to its widespread acceptance among drivers and passengers: it behaves like a conventional seat belt and operates identically.

ZF used a special textile processing method for this innovation. Heating conductors are woven into the seat belt structure. The contact elements for the electrical heating circuits are positioned so that they do not interfere with belt operation or retraction. No special belt retractors are required in other installation positions. Since all relevant seat belt characteristics remain the same, there are no additional procedures or qualifications for the manufacturer. The heated seat belt is in no way inferior to its conventional counterparts in terms of occupant protection.