We want to make the impossible possible for you - with a focus on your individual expectations of our products. Our passion for perfect motion is constantly leading us down new paths. This results in screw drive solutions that bring your innovations to the forefront of the market. There is no way around the aluminum screw drive.
The goal of technical progress is not just to achieve more, but to be able to do many things better with new technologies and processes. The need to solve practical tasks is perpetual. The latest technologies and materials stimulate mechanics and constantly reformulate the demands placed on it. This is why mechanics is a living science. The Swiss thread specialist successfully exploits the opportunities this offers and has managed to establish itself in the drive technology niche with its customized rolled thread drives. The potential of lightweight construction with aluminum is unmistakable, even for the simplest movement elements - combined with a sophisticated, special thread form, the cold-formed aluminum threaded spindle becomes an unbeatable mechanical drive component, for example in the door market: vehicle door systems.
A thread review - and there's no end in sight
When the average consumer looks at a spindle and a nut, they probably first imagine a typical fastening element. However, there are basically two mechanical areas for which a thread is used - fastening and movement. The invention of the threaded spindle is attributed to the Greek polymath Archimedes (287 - 212 BC). According to Pliny, a very important application of the moving screw emerged from the 3rd decade BC. Roman wine presses worked with spindles made of oak wood with impressive diameters. In order to achieve the necessary efficiency, huge wooden trunks had to be screwed up with a sliding threaded spindle so that the mash in the press basket could be pressurized.
Along with the changing times, the requirements for mechanical motion elements, i.e. screw drives, have changed and increased. Because wherever a rotary motion has to be converted into a linear motion (or vice versa), they are used at all levels of industry, even after 2300 years of technological history.
Materials help determine progress, even for screw drives
When it comes to mobility, billions of people rely on the reliability of rail and commercial vehicles in public transport. Energy efficiency, resource conservation, noise and pollutant reduction play a fundamental role in sustainable mobility concepts. In current materials research, however, "cheaper, lighter, stronger" also determines the key trends. Weight savings, CO2 emissions and fuel consumption can be reduced with light metal, and greater ranges can be achieved. Aluminum offers light weight with consistent stability, high load-bearing capacity and excellent machinability, which fascinates Eichenberger's developers enormously.
Centerpiece door operator
Delays and unforeseen incidents can easily occur in the boarding systems of all types of vehicles, be they buses, coaches, fire or rescue vehicles, metro and commuter trains, streetcars or high-speed trains. The quality of automatic sliding door systems therefore has a decisive influence on the safety and comfort of passengers and also on economic efficiency. High-speed trains can reach speeds of over 300 km/h. Imagine the forces at work, also in terms of air resistance and wear. Resistance, for example, increases as the square of the speed. So if the speed doubles, the air resistance quadruples. At the heart of these door systems is the linear drive. The aim of the designers from CH-Burg was to develop a more cost-effective solution for the movement tasks inside these drive units.
Innovations do not fall from the sky
Great effort, robustness, precision and reliability must be guaranteed in the tightest of spaces. The doors should slide easily and quickly. In the event of a power failure, the spindle-nut system must not be self-locking. Emergency opening must be possible by hand at any time. Major innovations are always the result of hard development work. Eichenberger succeeded in producing the cold-rolled aluminum lead screw with a special profile, diameter 20 mm, pitch 80 mm.
Only when the various components (ideal raw material/alloy, flawless cold forming, thread rolling tools specially manufactured by Eichenberger for the rolling process) are in perfect harmony can the material flow be optimized for a high pitch ratio of 80 mm. The Swiss thread specialist is able to offer development, production and quality assurance at the same time, so the flexibility in the manufacturing process or in the creation of prototypes, including thread rolling tools, is remarkably high. Potent know-how is also essential when it comes to designing the tools for the internal thread of the plastic nut. Thanks to these factors, production can be flexible and competitive even at expensive locations.
Speedy steep thread spindle made of aluminum, e 20 mm / pitch 80 mm
In this case, it is a further development of the spindles that are already used in sliding door applications. The innovative combination of the special hard-anodized aluminium 20 / 80 pitch threaded spindle and the plastic nut (nut material depending on the application) is designed in such a way that the spindle can be manufactured using the cold forming process. The thread rolling process is known to offer remarkable advantages in terms of hardening, roughness values and notch sensitivity.
The special profile of the thread provides a completely different support. The tilting moment is absorbed via the outer diameter of the spindle, which ensures smooth operation and prevents jamming.
The plus points at a glance
The aluminium threads, which have already been massively hardened by thread rolling, are given an even more resistant surface by further refining the outer layer or hard anodizing. This results in an additional reduction in the coefficient of friction and very good sliding properties. These values and, of course, the protection against corrosion, are the main reasons for a long service life.
What sounds so simple can only be achieved with a wealth of experience gained over many decades, a high level of quality awareness and modern machinery. The dynamic ratio of 80 mm pitch and 20 mm diameter allows a very high traversing speed. To achieve such a high nut speed, a single-start standard trapezoidal spindle with a diameter of 20 mm would have to rotate over 16 times faster. In addition, the low speeds have a very positive effect on wear and noise generation.
In terms of price, the new machine is absolutely impressive. Efficient, fast production is possible, which has an advantageous effect on the price, especially for large quantities. For the Swiss thread roller, thread forms that are outside the standard are the sought-after challenges. On request, customer and solution-oriented diameters and pitches can also be realized for aluminium spindles.
Service provider in development
Eichenberger Gewinde AG is a company with clear objectives: The rolling - i.e. cold forming - of threads and the production of screw drives (spindle and nut). Using state-of-the-art production methods and by developing new dimensions, Eichenberger supports the customer in "his" innovation.
