Innovative pulleys

Project description

The origin of the invention and the idea behind the innovative CAFFARO pulleys

The CAFFARO company, drawing on its extensive experience in the automotive industry, decided to create innovative pulleys (rollers) guiding multi-ribbed belts. Our main goal was to develop a product that would not only reduce the consumption of materials and energy and reduce the amount of waste, but also increase the durability and efficiency of the pulleys. Thanks to the unique spatial design, our innovative pulleys provide additional cooling, which is particularly important when transferring increased thermal and mechanical loads in micro and mild-hybrid drives.

Innovative CAFFARO pulleys

Our pulleys represent two advanced technological families:

Pulleys with two cooling windows made of 100% plastic.

Pulleys with three windows, having a steel skeleton combined with plastic (so-called hybrid pulleys).

Hybrid pulleys are designed to operate under high mechanical loads in hybrid drives, distinguished by an innovative way of combining a steel core with plastic, which is a unique solution on a global scale.

The research and testing process – from concept to finished product

From the beginning of work on the new pulleys, our activities were based on intensive research and testing. In order to thoroughly understand the thermal phenomena occurring around combustion engines, we conducted thousands of kilometers of tests in different cars, on different routes and in different climatic conditions. These tests allowed us to collect the necessary data, which were the foundation for further work on the wheel model.

Based on the information collected, we created mathematical models of different pulley variants, which were then tested using advanced thermal and mechanical simulations in FEM programs. Thanks to these tools, we were able to analyze the behavior of the wheels under different loads and optimize their design before starting to produce prototypes.

Another key element of our research was the construction of a unique climate chamber that simulated the operation of a hybrid drive and allowed us to study the behavior of wheels in different temperature conditions. In this chamber, we conducted a series of tests aimed at assessing the resistance of the wheels to changing operating conditions and their efficiency in dissipating heat.

In parallel with the laboratory tests, we produced a number of different prototypes, which we subjected to detailed mechanical, temperature and destruction tests. For example, the tests included fatigue tests, during which the wheels were subjected to long-term load, simulating real operating conditions in cars. We also conducted thermal tests, where the prototypes were exposed to extreme temperatures to check their resistance to extreme conditions. During one of the tests, the prototypes were mounted on real cars that underwent full test cycles on dynamometers and in real road traffic. For example, one of the road tests included a 10,000 km drive in different climatic conditions, from hot days to frosty mornings, which allowed us to thoroughly check the durability of the wheels in a variety of situations.

Thanks to these tests, we were able to select the optimal shapes and materials for the new pulleys, which allowed us to produce a series of prototypes that passed final tests confirming the expectations. Our hybrid pulleys, replacing traditional steel pulleys in hybrid drives, are characterized by the ability to reduce bearing temperatures by 10% compared to traditional solutions, which significantly increases their durability.

Key advantages of innovative CAFFARO pulleys

The new pulleys offered by CAFFARO are lighter than those currently used, which means lower material consumption, both plastics and metal. The patented wheel cooling system, created as a result of two years of intensive research and development, ensures effective heat dissipation from the movement of the bearing, the combustion engine block and additionally cools the electric machine in micro and mild-hybrid systems.

The lighter construction of innovative plastic and hybrid pulleys reduces the inertia of the system, which translates into reduced fuel consumption, lower load on multi-groove belts and the engine combustion. Thanks to the longer service life of the tensioner system, resulting from lower loads, the number of replacements of car parts is also reduced, which in the long term contributes to reducing the amount of waste and the global material and energy costs of producing parts.

Our pulleys are dedicated to cars with engines using multi-ribbed belts, mounted both transversely, longitudinally, V-type and boxer. We especially recommend them for cars equipped with the micro and mild-hybrid systems.

Application

Our pulleys are already used as replacements in car brands such as Volkswagen, Opel, BMW, Mercedes, Renault, Toyota, Suzuki, Audi, Skoda, Fiat, Nissan, and many others. CAFFARO has the ISO 9001:2015 quality management certificate and the IATF 16949:2016 automotive standard by TUV SUD, yet our offer is available in the largest and most renowned TecDoc automotive parts catalog.

Worldwide innovations

The patented shape of the new CAFFARO pulleys ensures better heat dissipation from the bearing, which leads to a 10°C reduction in wheel temperature, thus increasing their durability by 50%. The innovative hybrid design, combining a steel skeleton with a plastic housing, ensures excellent heat dissipation from the bearing, while reducing the weight of the pulley. As a result, our hybrid pulleys are significantly lighter than their metal counterparts, which translates into lower fuel consumption and lower raw material consumption.

All these innovations contribute to a significant reduction in material and energy consumption in production, as well as to increased durability and efficiency of hybrid drive systems. CAFFARO is proud to offer products that not only meet but also exceed customer expectations, while providing greater environmental protection.

Widespread

Time for practice

A photo of the first version of the Test Stand (SB1), from which we began our tests. We tested the capabilities of the designed micro, mild-hybrid system simulator on it.

We printed the first prototypes on our 3D printer. They were not full-fledged pulleys that could be used for tests – their strength cannot be compared to those manufactured using the target method. However, they allowed us to “take in hand” the concept that had come to the minds of the designers.

A photo of “Test Stand No. 2” during operation. This is a significantly expanded stand compared to the first version (SB1). After positive tests on SB1, we expanded our test stand with additional functions and “closed” it in a so-called climatic chamber, allowing us to control the temperature and humidity conditions in a very wide range. Additionally, we equipped the chamber with a special sight glass that allows us to observe the working system without disturbing the set conditions inside the chamber. Finally, we equipped SB2 with a system for monitoring the condition of the bearings during the tests.

The photo shows the interior of “Test Station No. 2”. The system is equipped with a drive shaft and a shaft simulating a load. All this to best reflect the working conditions in the micro, mild-hybrid system.

Close-up of the thermal camera during the operation of “Test Station No. 2”, showing the temperature distribution in the tested pulley and drive belt. In order to use the thermal imaging, we had to equip the SB2 with a special sight glass (window) that allows infrared radiation to pass through, so we could obtain the correct temperature measurement.

Our pulleys were tested in various conditions. The above photo shows the beginning of the test at a temperature of around -40°C. Everything is just like in everyday use, starting the engine on a frosty winter morning and gradually reaching the target temperature of the pulley, belt and their surroundings (engine chamber).

The project involved, among other things, a laser that cut “steel baskets” from a sheet of metal – an element of the hybrid pulley skeleton.

Taking into account road safety, we could only perform some of the tests in cars moving on public roads. Therefore, more complicated tests, especially those requiring external measuring equipment, were performed on a chassis dynamometer using a simulated road test.

We designed injection molds for our innovative pulleys. The molds have unique molding inserts made in accordance with models optimized during thermal and strength calculations.

Ultimately, we achieved the effect as in the photo above – a ready patent pulley in an injection mold.

Awards, distinctions - recognition by Experts