Permanent Magnet Stepper Motors

Permanent Magnet (PM) motors use permanent magnet rotors and are commanded by electrical pulses. They are widely used in printers, copies, and scanners, among other applications. They are also used to operate valves in household water and gas systems as well as drive actuators in automotive applications.

One of the main benefits of the PM stepper motor is that, in addition to being electronically commutated like a brushless DC motor or any other type of stepper motor, the PM stepper motor requires no “teeth” as are typically found in the variable reluctance (VR) stepper motor. This makes the permanent magnet stepper an extremely popular choice for many motor applications.

Extensive in-house machining and production capabilities enable NMB to manufacture stepper motors with a wide variety of custom features.

Basic Structure:

The stator section of the PM stepper motors consists of coils, stator yoke, in/out terminal and stators molded together in one piece by plastic resin. PM stepping motors are assembled simply by combining the stator with rotors of cylindrical permanent magnets.

Characteristics of the PM step motor:

  • Increase of holding and dynamic torque over conventional products in excess of 15%. Capable of complying with diverse product demands by changing the combination of shaft, front plates and wire harnesses.
  • Fully automated coil assembly.
  • Capable of complying with automated motor assembly processes.
  • Reduction of steps required from order to delivery.

Custom Features and Options

Listed below are some of the features and options available for NMB Permanent Magnet (PM) stepper motors.

motors are PM stepper motors with a planetary gear box.
(Lead Screw) motors are permanent magnet (PM) motors with a non-standard threaded shaft (e.g. molded plastic thread).
(Linear) motors are linear actuators based on PM construction.
Permanent Magnet Stepper Motor Cutaway

Permanent Magnet Stepper Motor Cutaway
  1. Windings - An encapsulated stator design gives greater dimensional control and improved thermal characteristics.
  2. Mounting Plate - Custom and standard shaped mounting plates are available. Mounting holes can be:
    • Threaded
    • Tapped
    • Slotted
    • Custom
  3. Permanent Magnet Rotor - Three different types of permanent magnets are available.
    • Ferrite Plastic Magnet
    • Ferrite Sintered Magnet
    • Nd-Fe-B Bonded Magnet
  4. Bushings and Bearings - Long life oil impregnated bushings are used in PM, PG, and PL (lead Screw) type motors. NMB ball bearings are used in PL (Linear) type motors.
  5. A variety of shaft, gear & pulley options are available.
    • Custom Lengths
    • Single & Double Shafts
    • D-cut/s
    • Turn Downs
    • Threaded
    • Knurled
    • Grooved
    Gears & Pulleys:
    • Machined
    • Plastic Molded
    • Powdered Metal (Sintered)
  6. Connector - Motor side connection method & lead wire options.
    Lead Wire:
    • Lead wire exit direction/ exit angles
    Motor Side Connection Method:
    • Wire Holder type connector
    • Printed Circuit Board (PCB) with Connector
    • Flexible Printed Circuit (FPC)
  7. Wire Leads - Driver side connector options:
    • Standard
    • Special Order (Non-NMB standard)
    • None (Flying leads)