Choosing Between a Brushless DC Motor and a Coreless Push Rod Actuator

Motion Selection Guide

In a space-constrained machine, motor diameter is only one part of the fit. The useful starting point is the output requirement: rotary torque or linear thrust, at a defined speed and duty cycle.

Rotary Motion Torque + Speed

Linear Motion Thrust + Speed + Stroke

For rotary motion: slotless brushless DC motors

DINGS’ slotless brushless DC motors provide compact rotary motion for applications where a small motor envelope, responsive speed control and smooth operation matter.

Start by defining the required continuous and peak torque at the output shaft, operating speed, supply voltage and available diameter and length.

For a rotary axis, start with the torque required at the operating speed and then account for the complete motor assembly.

View Slotless BLDC Motors → Download Slotless BLDC Catalog ↓

If the motor cannot deliver the required torque directly, a gearbox may help, but it also changes output speed, overall length and reflected inertia. Position control may require encoder feedback.

Size the complete motor assembly, including those components, against the space available in the machine.

For linear motion: coreless push rod actuators

When the output needs to push or pull, a DINGS’ coreless push rod actuator combines a compact brushless motor, reduction mechanism and screw-driven linear output in a single assembly.

The cataloged family covers motor diameters from 8 to 22 mm and rated thrust from 25 to 750 N.

Coreless push rod actuators integrate the rotary drive and screw-driven linear output into a compact actuator package.

View Coreless Push Rod Actuators → Download Push Rod Catalog ↓

Choose a configuration using the force required throughout the stroke, travel speed, stroke length and duty cycle.

Lead screw and ball screw options offer different force, speed, efficiency and backdriving characteristics. The highest thrust rating is rarely enough information to select an actuator on its own.

Example: 10 mm coreless push rod actuator configuration

Dimensional drawings help verify the complete actuator envelope, mounting interface and feedback configuration before integration.

Which product fits the axis?

Output requirement	Starting point	Check before selection
Controlled rotary motion	Slotless brushless DC motor	Torque at operating speed, duty cycle, feedback needs and space for any gearbox
Compact linear push or pull	Coreless push rod actuator	Thrust at the required speed, stroke, duty cycle and screw configuration

For example, a compact rotary joint and a finger driven by a linear linkage may have similar space limits but need different solutions. The joint calls for a rotary torque calculation; the finger actuator calls for a force and stroke calculation.

Start at the load, not the motor. Selecting from the load at the output helps avoid finding a motor that fits, then discovering the complete mechanism does not.

Need help sizing an axis?

Send DINGS’ Motion USA your available diameter and length, supply voltage, load, speed, stroke and duty cycle. For rotary axes, include the required continuous and peak torque; for linear axes, include the required push and pull force.

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