Linear actuator components: what makes for a best seller?

A linear actuator system consists of a number of key parts, all of which work together to move a load from one area to another. For any actuator system to perform consistently at its optimum level, it needs the correctly specified motor, linear gearbox, couplings, and control system.  Here we look at our most popular motors, couplings and gearboxes to find out why they are best sellers and what role they perform.

Servo Motors

When it comes to the motors providing rotational speed for a linear actuator system, stepper motors, DC motors, AC motors, direct-drive linear motors, and servo motors are all suitable.  Whilst application requirements (precision, cost, speed, load, complexity) often determine the type of motor used in a linear actuator system, servo motors are our most popular customer choice.

What are the benefits of a Servo motor?

A servo motor, which forms part of a servo system alongside a servo drive and associated cables, provides high-speed, high-precision motion.  Their accuracy partly derives from their closed-loop feedback (using encoders or resolvers), so the system knows the exact position, speed and torque.  This design provides superior performance and control compared to more conventional systems using AC motors, DC motors, stepper motors, etc.

The key benefits that servo systems offer include:

• Dynamic motion
• High positional accuracy
• Low cogging torque
• Wide speed range
• Constant rated torque across the speed range
• Highly efficient and reliable
• Compact size

As you might expect, servo systems are more expensive than most other options, as well as being more complex to control, but when precision is required, they are hard to beat.

Servo Motors available from Matara

We supply servo motors from Delta Line, a leading global manufacturer with over 40 years’ experience.  Customers can select from the Delta ASDA-B3 range for 1ph/230VAC mains supplies and, for more demanding, higher power applications, the Delta ASDA-A3 range, where the supply is 3ph/400VAC.  Due to the low rotor inertia using rare earth magnets, both ranges are designed for high-duty, high-dynamic applications, where speed and position control are key requirements. 

Delta ASDA-B3 Servo System: this system consists of a high-dynamic servo motor with an integrated 24-bit absolute encoder and a compact servo drive.  Due to its versatility, wide speed range, and precise control, the B3 range is an ideal compact AC servo solution for a wide variety of applications.

• Power 100W – 1.5kW
• 24-bit Absolute Encoder
• High Load Inertia Mismatch Ratio
• Low Cogging Torque
• Safe Torque Off (STO) Function
• Motor Speed 6000rpm, Max Torque 350%

Delta ASDA-A3 Servo System: this system also consists of a high-dynamic servo motor with an integrated 24-bit absolute encoder, but comes with an extremely slim servo drive.  The A3 Servo drive is feature-rich, including integrated motion control capabilities, CAM function, auto-tuning, external full closed-loop positioning, notch and vibration suppression filters

• Power 400W – 15kW
• 24-bit Absolute Encoder
• 3.1kHz Bandwidth, High Responsiveness
• Integrated Motion Control and CAM function
• Safe Torque Off (STO) Function
• Motor Speed 6000rpm, Max Torque 350%

Both ranges of motors seamlessly fit to our linear actuator and belt actuator products, although, where required, can be tailored to suit your specific application thanks to our in-house facilities and expertise, and our strategic partnership with sister company Gapp Automation.

Shaft Couplings

In a linear motion system, a coupling is a mechanical component that connects the motor shaft to the screw shaft (ballscrew, leadscrew, or other transmission element). Its role is to transmit torque from the motor to the screw while compensating for misalignments and protecting components from excessive stress.

Couplings available through Matara are suitable for many situations, from the transfer of very low torque ratings in miniature drives, up to very high torque ratings in high-load applications.

Shaft Couplings available from Matara

Our most popular couplings are manufactured by our sister company Gapp Automation, which, along with KJN Automation and ourselves, forms the Rubix Motion, Control and Automation (MCA) division.  Rubix is Europe’s leading distributor of industrial maintenance, repair and overhaul (MRO) products and services.

GTR series: This torsional rigid disc coupling with angular backlash is composed of three main items: two fully turned hubs, made in steel UNI EN10083/98; the disc pack, in stainless steel AISI 304 C; with connection screws in steel class 10.9.  A “double” version, GTR/D, is also available, which includes a spacer made to length, also built in steel UNI EN10083/98, fixed between the hubs and the two disc packs.  The GTR series of shaft couplings are ideally suited to high speed applications where high reliability, precision and an optimum weight/power ratio is required.

GSF Series: also designed for high speeds and fast reversing, GSF bellow couplings provide torsional rigidity with low inertia without compromising reliability.  Modular in design – for maximum flexibility – the two shafts are connected to the bellow exploiting a simple mechanical system, by properly sized radial screws and without using bonding agents. In this way, the coupling can operate and withstand high temperatures, up to 300°C.

GAS Series: an elastomeric coupling with compact dimensions, GAS is composed of two hubs made in steel UNI EN10083/98, fully turned with one elastomer.  The latter allows for vibrations to be absorbed and silent transmission, plus compensates for unavoidable misalignments between the shafts.  The hub’s tooth profile is designed to allow the elastomeric element to work only by compression and not in shear, allowing for the long life of the coupling in high-reversal or load applications.  GAS is composed of different options that can be assembled to get the right configuration for the application, such as an extended hub for connecting long shafts and a small hub for confined spaces.

Planetary Gearboxes

In a linear motion system, a planetary gearbox is used to convert the rotational motion of a motor into a regulated, high-torque linear movement. The gearbox provides precise control over speed and torque by distributing the load across multiple internal gears, which allows for a compact and efficient system with high accuracy, smooth operation, and minimal backlash. This makes them ideal for applications like robotics, automation, and precision machinery that require consistent and reliable movement.

Planetary Gearboxes available from Matara

As with shaft couplings, our most popular mid-range planetary gearboxes are made by Gapp Automation.  The PGC series and the PGE series both come in three precision levels with seven frame sizes to choose from, 50-235mm.  Their popularity comes from their versatility, precision and performance.

• Torque capacity range: 10 Nm through 1670 Nm
• Inline configuration with output shaft 13 mm through 75 mm diameter
• Caged planet carrier: with precision planet gear set
• High performance, efficiencies and low acoustics
• Wide range of ratios: 5 single-stage ratios and up to 9 two-stage ratios
• Square servo and step motor input: accommodates 50 mm through 235 mm, with optional sizes available
• Service life lubricant

The PGC Series output bearings deliver radial load capacity as high as 11120 N, and axial capacities up to 8560 N, whilst the PGE Series’ capacity is 13500 N and up to 7300 N respectively. 

If you would like assistance in selecting the right component for your linear actuator, contact us at [email protected] or call us at +44 (0) 1684 850000.