Beam Couplings for Robotics


Ruland offers beam couplings for robotic applications. The beam couplings are machined from a single piece of aluminium or stainless steel with several spiral cuts for higher torsional stiffness and torque capabilities than single beam couplings. The multiple-beam pattern allows Ruland couplings to accommodate higher amounts of parallel misalignment than single beam couplings, while also allowing for high angular misalignment and axial motion.

Servo motor coupled to a lead screw with a zero-backlash coupling for precise motion control

Medical and surgical robots often combine a stepper or servo motor to a lead screw or encoder requiring a zero-backlash coupling for precise motion control. These systems have limited torque requirements; however, they may need high responsiveness and flexibility making a beam coupling a suitable choice. Ruland’s four-beam style couplings (P- and MW-series) have a more compact design that is paired best with light-duty applications such as servo motor to encoder connections. The six-beam style coupling (F-series )has increased torque capacity and is well suited for light-duty power transmission applications such as connecting a motor to a lead screw.

Ruland multiple-beam couplings are manufactured with a balanced design for reduced vibration at speeds up to 6,000 rpm. Clamp-style F-series couplings are supplied with Ruland’s proprietary Nypatch anti-vibration coating. Nypatch ensures that the hardware stays in place through intense vibration and movements over time whereas untreated hardware may back out from harsh vibrations.

Ruland beam couplings are offered in clamp and set screw styles with inch, metric, and inch to metric bore combinations ranging from 3 mm to 20 mm. They are available in 7075 aluminium for lightweight and low inertia or 303 stainless steel for higher torque and torsional stiffness. Special designs such as anodizing, non-standard bore sizes, and special tolerances are available upon request.

All Ruland zero-backlash beam couplings are manufactured from select North American bar stock in Ruland’s factory in Marlborough, Massachusetts, under strict controls using proprietary processes. Full product information, 2D and 3D CAD files, installation videos, and more are available on


  • Higher torque and torsional rigidity than single beam couplings
  • Balanced design for reduced vibration at up to 6,000 rpm
  • Accommodates parallel misalignment, angular misalignment, and axial motion
  • Zero-backlash for precise motion control
  • RoHS3 and REACH compliant
  • Carefully made in Ruland’s factory in Marlborough, Massachusetts, and available for immediate delivery

Ruland Manufacturing Co., Inc.
6 Hayes Memorial Drive
Marlborough, MA 01752, USA
Phone +1 508 485 1000
Fax +1 508 485 9000
E-mail [email protected]