What is the difference between harmonic and RV cycloidal reducers?

Harmonic (strain-wave) reducers use a flexible spline for very compact, low-backlash reduction. RV cycloidal pin-wheel reducers use cycloidal gearing for high torque and rigidity in heavier-duty applications. SEI engineers can help match the type to your joint or axis requirements.

Can harmonic reducers mount directly to my motor?

Yes. CSF, SHF, and flange-mount series support standardized input couplings and adapters for servo, stepper, and BLDC motors. Contact us with your motor frame and torque requirements.

Products

RV / Harmonic Reducers

Harmonic gear reducers (strain-wave gearboxes) use elastic deformation of a flexible spline to achieve high reduction ratios in a compact envelope with low backlash and high accuracy. They are widely used in robot arms, precision positioners, and medical equipment.

SEI also supplies RV cycloidal pin-wheel reducers and integrated flange-mount units for applications requiring high torque density and torsional rigidity. Multiple series cover simple unit types through heavy-duty flange configurations.

Request a Quote (408) 980-9822

Models & Series

HARMONIC REDUCER

RV REDUCER

Key Features

Compact high-ratio reduction in a lightweight package
Low backlash and high positional accuracy
High torque density for robotic joints and positioners
CSF strain-wave harmonic reducer series
RV cycloidal pin-wheel RVC and RVE series
SHF simple unit and RCA/REA flange-mount options

Specifications

Product types	Harmonic (CSF, SHF) and RV cycloidal (RVC, RVE, RCA, REA)
Typical applications	Robot arms, wafer handling, aerospace mechanisms
Integration	Simple units and flange-mount configurations
Customization	Ratio, flange, and adapter options on request

Configuration Options

CSF cup-type flexspline harmonic reducers
SHF simple unit harmonic reducers
RVC and RVE RV cycloidal pin-wheel reducers
RCA and REA flange-mount cycloidal units
Custom adapters for servo, stepper, and BLDC inputs

Applications

Industrial and collaborative robot arms
Semiconductor wafer handling and positioning
Medical and surgical robotics
Aerospace and defense mechanisms
Machine tools and precision indexers

Product Series

CSF HarmonicSHF Simple UnitRVC / RVE CycloidalRCA / REA Flange Mount

FAQ

What is the difference between harmonic and RV cycloidal reducers?: Harmonic (strain-wave) reducers use a flexible spline for very compact, low-backlash reduction. RV cycloidal pin-wheel reducers use cycloidal gearing for high torque and rigidity in heavier-duty applications. SEI engineers can help match the type to your joint or axis requirements.
Can harmonic reducers mount directly to my motor?: Yes. CSF, SHF, and flange-mount series support standardized input couplings and adapters for servo, stepper, and BLDC motors. Contact us with your motor frame and torque requirements.