Electric windows for yachts

What was needed: drylin® ZLW belt-driven linear actuator, drylin® DC motor and a drylin® D5 motor controller

Requirements: In marine environments, electrical components must be compact, highly resistant to corrosive saltwater, and capable of withstanding extreme temperature fluctuations. Just as importantly, they need to operate reliably with minimal maintenance.

Industry: Ship and boat building

Application success: Thanks to their low installation height, the ZLW belt-driven linear actuators are ideal for light adjustment and positioning tasks in space-constrained applications. In addition, the actuators are corrosion-resistant, making them well-suited for demanding environments.

Glaskeil, founded in 1898 by master glazier August Keil in Würzburg, has developed into a specialist for ready-to-install and customized glass and plastic products for yacht building.

Electric windows offer more comfort and luxury than conventional windows, as they can be opened and closed at the touch of a button. While this has long been standard in cars, such windows are still a rarity on yachts. Here, electrical components not only have to be compact, but also resistant to aggressive salt water and extreme temperature fluctuations. They should also be as maintenance-free as possible.

"The search for a supplier of electrical linear guide technology that could meet the high demands of upmarket boatbuilding was correspondingly challenging," recalls Glaskeil developer Mirco Eisenhauer.

The Glaskeil designers were faced with several challenges: The products had to be very space-saving, as the available space on boats is limited. In addition, corrosion, especially from salt water, is a major problem.

As these are boats in the premium segment, the motors installed had to be as maintenance-free and quiet as possible in order to offer customers a satisfactory experience. The control system should also be convenient. Modern programmable logic control systems (PLCs) are often oversized for simple automation tasks such as raising and lowering a window pane.

"With igus® from Cologne, we finally found a system that is space-saving, robust, wear-resistant and virtually maintenance-free. And thanks to the plug-and-play principle, it saves us design work."

The key component of this solution is the drylin® ZLW belt-driven linear actuator, which is mounted along the longitudinal struts of the black window frame on the right and left. With a clearance height of just 31mm, these belt-driven actuators are the perfect choice for light adjustment and positioning tasks, especially when space is limited.

The windows are driven by a DC motor from igus®. With a flange dimension of 42mm, this is also very space-saving, as it does not require a motor flange, coupling or complex external power electronics. It is also resistant in a wide temperature range between 14 °F and 140 °F. When the yacht passenger presses a switch, the motor starts up. The belts now move on both sides of the window frame, connected to each other by a synchronized shaft. And thus the carriages mounted on the profile guides, to which the window pane is in turn attached.

The carriages slide on the aluminum rail via bushes made of high-performance plastic using the WJ200UM series housing bearings . Thanks to microscopically small solid lubricants, hygienic, low-friction and quiet dry operation is possible without external lubricants. This minimizes the need for maintenance.

Glaskeil also uses the dryve D5, an igus® motor control system that enables fast commissioning. Designers only need to connect the voltage source, control signals and the motor to the output stage. A signal, triggered by a connected button, then starts and stops the motor. A second signal is used to change the direction of rotation. The speed of the output stage can be set via eight microswitches on the housing. Settings can also be made via smartphone, tablet or laptop. Glaskeil can then set the travel mode, positions, accelerations, speed and pause times of the linear axis in just a few minutes via an intuitive browser interface. The high rated current of 10 A and 30 A peak current also produces powerful and dynamic movements on request.

Another advantage: thanks to a sophisticated combination of materials and microchips, the power amplifiers operate particularly quietly and with low vibration at all speeds. "We don't have to worry about annoying noises, which can occur with many inferior power amplifiers," emphasizes Mirco Eisenhauer. "This is an important point for our customers in the premium segment."