Siemens Direct Drives – Linear Motors 1FN


Maximum dynamic performance for linear motion -

Our linear direct-drive motors distinguish themselves as a result of their innovative design and loss-free power transfer. Our linear motors are available up to rated forces of 10,375 N and achieve traversing velocities of more than 800 m/min – for the highest degree of productivity. The complete series of direct-drive motors stands for the highest dynamic performance, precision and cost-efficiency – in all applications.


Current is directly transformed into motion without having to go through an intermediate mechanical step – this is the principle of operation of Siemens synchronous direct drives. Just like a magnetic levitation train, the force is transferred without contacting. The driving force is achieved through a travelling electromagnetic field in the generally moved primary section as opposed to the magnetic secondary section. The primary section is mounted on linear guides travelling at high speed and with track precision. The force transmission elements, which are generally required for a conventional electromechanical drive, for example, gear units, ball screw, belts or rack and pinion, are no longer required. The mounting space required is reduced, the mechanical design of your machine simplified, the machine availability increased and operating costs lowered.


Linear motors are the ideal solution if linear motion has to be executed. The reason for this is that the effects of elasticity, play and friction can be avoided to a large extent. The same goes for natural vibration in the mechanical drive train. The forces are directly transferred which results in the highest dynamic performance but at the same time with high precision – almost without play and without overshooting. All of this is achieved without the motor components being subject to mechanical wear and without jerky motion.


The traversing ranges that can be achieved with 1FN3 linear motors start at approx. 20 mm and their length is limited solely by the maximum cable length for connecting the primary section or the maximum length of the position measuring system. Any traversing length can be implemented by mounting magnetic secondary sections side by side spaced at 120 mm or 184 mm lengthwise.


The principle of operation of a linear synchronous direct drive results in a high temperature increase of the primary section. However, for Siemens linear motors, this thermal stressing is neutralized to a significant extent. The motors which are designed for especially high continuous forces have integrated water cooling. For precision applications, we offer motors with the Thermo-Sandwich type of construction. With this special type of construction, a second precision water cooling reliably limits the temperature rise at the mechanical interfaces to the machine to a max. of 2 K or 4 K.


Since mechanical power transmission elements and the associated backlash and frictional losses are dispensed with, linear motors boast the following characteristics:

·         Outstanding dynamic response

·         Very high traversing velocities

·         Extremely precise

·         Easy installation

·         Wear-free

·         Enable a simple, compact machine design

·         High electrical efficiency


When suitable measuring systems and cooling methods are employed, linear motors achieve a positioning accuracy in the nanometer range.


1FN3 linear motors are therefore suitable for all applications that require high acceleration rates and velocities for highly productive handling or machining of parts. Thus, typical applications for linear motors are:

·         Machining centers

·         Turning machines

·         Grinding machines

·         Punching/cutting machines

·         Laser- or Water jet-cutting machines

·         Machines for processing wood/glass/plastics

·         Interlinking, handling, robotics

·         Measuring machines

·         Printing

·         Electronics production (pick&place, bonders)


We create unique motor solutions for every user. We can individually adapt the mechanical design and power to the particular application thanks to the wide variety and versatility of our motors and thanks to the modular component concept. For instance, for the linear motors, the basic motor can be extended by various components (cooling system, covers …). An optional cover for the secondary section makes the motors extremely robust against mechanical influences. Furthermore, you can use our motors in various mechanical versions – whether as classic single-sided solution or motors arranged in a mirror image to one another as double-sided design.


1FN3 linear motor – continuous load version: The power packs for high thrust

The high rated power of this series means excellent drives subject to high process forces and permanent acceleration. In addition, it has very low minimal cogging force.


1FN3 linear motor – peak load version: full power for maximum acceleration

This motor is an excellent drive for accelerating loads as a result of the high ratio between the peak and continuous load. The primary sections are designed as standard for water cooling. However, with the appropriate system design, natural cooling is also possible in certain cases.



The new “Electrical Gear Rack” 1FN6

With the linear motor 1FN6 from Siemens we are now offering another synchronous variant of a linear motor that is characterized by its non-magnetic secondary section. This can be used to implement extremely high dynamic applications with long traversing paths cost-effectively. The non-magnetic secondary section also allows a highly dynamic linear motor to be used under environmental conditions in which magnetic secondary sections are undesirable. Maximum forces of between 900 and 8080 N give the motors an impressive acceleration capability at maximum velocities of 170 to 540 m/min.


As the shape of the secondary section is reminiscent of a gear rack, and due to its possible use in place of a classical rack and pinion systems, the term "electrical gear rack" has been coined for the 1FN6 linear motor.


Typical areas of application:

·         Conveyors, assembly and transfer lines

·         Handling gantries and robotic applications with long traversing paths

·         Water jet and laser-cutting machines with long horizontal traversing axes


Integration in your machine

Furthermore, our engineers professionally support you in every phase, from the initial design through integration up to commissioning. You have a strong partner for synchronous direct drives with CNC Design. Our experienced application engineers will help you to significantly shorten the development time. Beyond this, CNC Design provides a global technical service and, when necessary, around the clock.