Engineering Notes

Introduction to the Stepper Motor Linear Actuator Attachment

Written by Johann Tang | Sep 30, 2024 4:00:00 PM

 

The popularity of micro linear actuators has been steadily increasing, driven by the need to increase productivity in confined spaces.  To help meet the demand of the miniaturization trend, Oriental Motor has developed a compact linear actuator that can be attached to an off-the-shelf stepper motor.

According to Verified Market Reports, "The Micro Linear Actuators Market Size was valued at USD 1.50 Billion in 2023 and is expected to reach USD 4.20 Billion by the end of 2030, with a CAGR of 15.85% during the forecast period 2023-2030."

Claude 3.5 Sonnet says, "The US micro linear actuators market could potentially see a compound annual growth rate (CAGR) of approximately 9-11% over the next decade. This would translate to a total growth of about 140-180% over the 10-year period."

This growth is anticipated to be driven by increasing adoption in medical and healthcare, industrial automation and robotics, consumer electronics, automotive (electric and autonomous vehicles), and aerospace/defense industries.

 

Topics covered:

  • What is the Stepper Motor Linear Actuator Attachment?
  • Installation 
  • What Makes It Unique?
  • Compatible Lineup
  • Application Examples

What is the Stepper Motor Linear Actuator Attachment?

The Stepper Motor Linear Actuator Attachment is a mounting adapter that includes a lead screw and a resin nut with high wear resistance.  It can be easily attached to off-the-shelf stepper motors, like a gearhead, and converts rotary stepper motion to precise linear motion (similar to an external type stepper motor linear actuator).

 

In this example, we show the Stepper Motor Linear Actuator Attachment by itself and a finished assembly with a PKP Series 42 mm frame size stepper motor.
 

With a built-in axial bearing mechanism, the Stepper Motor Linear Actuator Attachment can handle up to 100 N (with a 42 mm frame size stepper motor), and axial loads can be applied directly. 

The actuator can also provide an equivalent holding force to hold the load in place when power is removed or fails.

 

Installation

Since the Stepper Motor Linear Actuator Attachment does not include an anti-spin mechanism, it must be provided by the customer.  Without it, the nut will just spin in place and won't move anywhere.  In the image below, we show an example of a finished assembly of a Stepper Motor Linear Actuator Attachment, an anti-spin mechanism, support bearings, and a linear guide.  The product does not include limit switches or sensors, so they will have to be installed elsewhere, such as on the linear guide.

 

 

What Makes it Unique?

The Stepper Motor Linear Actuator Attachment can be installed to a stepper motor output shaft without a coupling mechanism, which reduces the number of required components for assembly, saves space, and speeds up design compared to custom-built linear actuators. 

In the example below, the number of components is reduced from 9 to 6 as we were able to eliminate the coupling, fixed-side bearing, fixed-side block, and a standalone leadscrew.

 

 

Introducing The Stepper Motor Linear Actuator Attachment

 

At this time, the Stepper Motor Linear Actuator Attachment is offered for stepper motors in the 42 mm and 30 mm frame sizes with stroke lengths from 30~300 mm, up to 10 kg of transportable mass (or 100 N thrust), and speeds up to 180 mm/s.  The repetitive positioning accuracy is +/-0.05mm.

 

Compatible Lineup

Various types of PKP Series high torque stepper motors and CVD Series bipolar microstepping drivers can be combined to build different types of stepper motor linear actuators.  In the diagram below, we show the combinations that's possible with our extensive product lineup.

 

Stepper Motor Options: PKP Series 2-Phase, PKP Series 5-Phase

Compatible Frame Sizes: 42 mm, 30 mm

Use the Standard Type for normal positioning applications Use a High Resolution Type for twice the resolution and better positioning accuracy Use the Encoder Type for closed-loop operation for reliability (line driver only) Use the Electromagnetic Brake Type to hold the load in place when power fails Use the Flat Type to reduce the length of the linear actuator to save space

Driver Options: CVD Series 2-Phase, CVD Series 5-Phase

Use the Pulse Input Type if you're sending a pulse train signal from a host controller. Use the RS-485 Type if you wish to use a host controller (PLC) via network command. Use the S Type if you wish to communicate via SPI or make your machines smaller. Use the Multi-Axis Type to control multiple motors via EtherCAT protocol.

 

By being the manufacturer of both the motor and the driver, Oriental Motor can provide unique ways to improve motor performance that other manufacturers cannot.  For example, the CVD Series drivers were designed for the best performance with PKP Series stepper motors.  Its current compensation control pairs actual motor winding data with unique driving algorithms to lower vibration and improve torque for more consistent performance.

The Stepper Motor Linear Actuator Attachment allows various types of basic stepper motor linear actuator systems to be built by mixing and matching different combinations of PKP Series stepper motors, lead screws, and dedicated CVD Series drivers.  If you're looking for better specifications like higher load capacity, better repetitive positioning accuracy, or built-in closed-loop absolute control, please browse our fully built, fully functional linear slide, linear cylinder, rack and pinion, or gripper systems.

 

Application Examples

For point-to-point applications where space is limited, such as syringe pumps and test tube transfer, the Stepper Motor Linear Actuator Attachment can get the job done for less.

This application examples shows how 3 sets of stepper motors and linear actuator attachments provide precise linear motion for syringe pumps in a slim profile.
This application shows how a stepper motor and linear actuator attachment transfers test tubes linearly from one location to another.  An external guide is recommended.

 

Have questions?  Our team is standing by and eager to answer any questions you may have.