Drives & Controls July / August 2022

n TECHNOLOGY MOTIONCONTROL PRODUCTS (MCP) has announced what it claims are the first linear motors that do not have any magnets in their tracks, thus reducing the need for rare-earth materials and cutting costs, especially for long travel lengths. The motors are also said to be easier and safer to assemble, without the usual strong magnetic attraction between the track and the moving forcer. Most conventional linear motors have magnets in their tracks, and coils in the forcers. When a current is applied to the coils, it creates an electromagnetic field. The linear track contains rare-earth magnets with alternating north and south pole segments along its length. The electromagnetic field generated by the coils interacts with the magnets to move the forcer along the track. Because the rare-earth magnets are powerful, care is needed when assembling and installing these motors, especially when they are close to other magnetic materials. In addition, sensitive or non-shielded electronic systems can be adversely affected by the strong magnetic fields. MCP’s new MMF linear motors use the same “magnetic field modulation” principle as conventional linear motors to control the interaction of the forcer with the teeth on the track. These teeth, moulded from a powdery ferrous material, are manufactured with a specific shape. When a current is applied to the coils, a magnetic field is induced in the teeth. By controlling this field, it is possible to control the position of the forcer relative to the track and thus to create motion. The only rare-earth magnets are inside the forcer and the number of magnets is not affected by the length of travel. MCP says that the performance of the MMF motor is comparable to that of a standard linear motor. There are two series: one delivers acceleration up to 22G, speeds up to 30m/s, and thrust values up to 538N; the other produces acceleration up to 24G, speeds up to 15m/s, and thrust up to 1,076N. The MMF motors have self-modulated ferrite alloy stators. Integrating the magnets with coils in the mover is said to result in a magnetic circuit that generates smooth thrust. The easy-to-assemble motors are said to exhibit high force densities and high operating speeds, with precision movements. They also ： n are safer and easier to assemble because there is no magnetic field in the stator; n exhibit low cogging forces and friction, increasing their life expectancy; n produce significantly less electromagnetic interference in the platen; n protect the forcer because fewer metallic particles are attracted by the magnetic field; n offer improved thermal characteristics; and n weigh less and have a simpler construction than conventional linear motors. www.motioncontrolproducts.com Enclosure Climate Control Whatever the scale...... ......we have the solution The linear motors with magnet-free tracks have special teeth shaped from a ferrous powder material Linear motors with magnet- free tracks cut costs A German sensor developer Ege- Elektronik Spezial-Sensoren has announced a device that converts signals from traditional analogue sensors to noise-free digital IO-Link signals. Depending on its configuration, the IOL- KONV-UIS-01 converter takes one or two analogue values (0-10V or 4-20mA) or switching signals from a sensor and converts them into digital signals, which it sends to an IO-Link primary device. Any conventional sensor from any manufacturer can be connected to the converter, regardless of its operating principles and measured values. The IO-Link converter also offers monitoring functions. If the power consumption or operating voltage of the connected sensor deviates from setpoints – due to corrosion, for example – it will send an error message to the controller. To protect its internal electronics, the IP67-housed converter incorporates temperature monitoring and short-circuit detection, as well as an adjustable shutdown function in the event of overloads. A multi-colour LED shows the operating status. https://ege-elektronik.com/en Device converts analogue signals to IO-Link