High-efficiency servo motors without brushes

Brushless DC Motors

  • Protection IP65
  • 3 phase sinusoidal winding
  • 4 frame sizes
  • Feedback: Resolver or encoder
  • Description
  • Good to know

  • Downloads

Brushless DC motors - high performance with compact dimensions

The brushless DC motors (SVTM A series) are fully enclosed and no additional ventilation is required. The DC motors have a standard protection class of IP65 on the housing. To ensure longer life, 200° class insulation materials are used. Thanks to the stator package design with winding in the slot and the neodymium magnets used, high power can be generated with small dimensions. The brushless DC motors are tested according to the EN 60034-18-41 standard regarding the partial discharge between the windings and to extend the range of application, the insulation materials used are UL certified. All brushless DC motors are available with shaft and key. Other operating voltage options are available upon request. The motors have standard adjustable M17 or M23 connectors, other connector or wiring solutions are also available upon customer request.

What are the coreless motors? by Josafatt Bernocchi www.servotecnica.com

Are you sure you know about coreless motors and their advantages? If the answer is "not much" or "just a little", then this article is for you. Let's start with a definition: a coreless motor is a brushless or brushed motor with a coil wound on itself and not on iron. For this reason, it is also called ironless. The winding of coreless motors has a typically "oblique" or "honeycomb" design to create a dense, self-supporting weave that is then held in place with the use of epoxy resin. In brush motors, the stator is composed of rare earth magnets and is located in the most internal part of the motor, while for brushless motors the magnet, always internal, is the rotor part. The selection of rare earth magnets and the construction technology of the coreless motors guarantee maximum power in the smallest possible package.

So why choose a coreless motor?
This innovative design offers several advantages, not least the elimination of the cogging effect. Cogging is an effect that machine builders do not like, typical of conventional permanent magnet motors. This effect can be defined as the "snap" that occurs when the tooth is aligned with the opposite magnet and passes through the intermediate unstable magnet. To learn more about cogging, please refer contact us. As you can easily guess, the absence of this effect will allow the great advantage of a more fluid and uniform motion.  A further advantage of coreless DC motors is their low level of electromagnetic interference (EMI) - in fact, the presence of the external ferromagnetic structure allows interference to be confined. This is particularly advantageous when there are other EM signals within the application, such as those produced by smartphones or medical devices. Coreless motors can also be used in battery-powered devices, as they absorb little current thanks to their characteristics. Other advantages are long operating lifetime, high overload capacity (no iron saturation), excellent heat dissipation, low inertia, high torque and speed, compactness and lightweight. High efficiency is a significant advantage. In coreless motors, the absence of the ferromagnetic core means the elimination of iron losses, which guarantees significantly higher efficiency when compared to traditional iron core direct current motors. In coreless motors, the rotor mass and inertia are reduced, producing more rapid acceleration and deceleration. These are key performances in high dynamic applications. You will also be pleased to learn that coreless DC motors are available in brushed and brushless versions. As the name suggests, the difference is whether the brushes are present or not. In the former, the current commutation in the stator windings and changes in magnetic field orientation is provided by brushes and commutator, in the latter they are generated electronically with the rotor position being given by special "hall sensors".
Needless to say, every type of coreless motor (with or without brushes) has its pros and cons and, in turn, reference applications. For brushed coreless motors, there are also fundamental differences in brush materials - typically graphite or precious metals. A specialist supplier such as Servotecnica of brushless motors and brushed coreless motors will be able to provide advice on the best solution for a specific application. Coreless DC motors are ideal for a myriad of dynamic applications, including robotics projects such as small positioning systems and pan/tilt systems. Medical devices such as prosthetics, insulin pumps, X-ray machines and laboratory equipment, also benefit from the use of coreless motors. Besides, there are numerous applications in particularly demanding sectors such as aerospace, defense and surveillance. We could give many other examples, ranging from automotive systems, wire tensioning systems, microscopes and electric screwdrivers, tattoo machines, golf caddies and massage chairs (to name but a few). With a coreless motor, the possibilities for designers are endless.
To find out more about how and at what level coreless motors can improve the performance of your application, contact our team of specialists.

Article No. Size □ Torque Peak torque Feature/Option Images 3D Data sheet Order Wishlist
SVTM A 01 60x60mm Up to 1.16Nm Up to 3.9Nm Low voltage, frameless Order
SVTM A 02 80x80mm Up to 4.39Nm Up to 16.3Nm Low voltage, frameless Order
SVTM A 03 115x115mm Up to 14.4Nm Up to 38Nm Frameless Order
SVTM A 04 145x145mm Up to 24.3Nm Up to 63.7Nm Frameless Order