Ruland manufactures three series of zero backlash beam couplings in inch or metric dimensions with bores ranging from 3/32" (3mm) to 3/4" (20mm). Flexible beam couplings in all three series are machined from a single piece of aluminum or stainless steel and feature multiple helical cuts. The multiple cut design provides higher torque capabilities and greatly reduced wind-up when compared to commodity type single beam couplings.
The P-Series, F-Series, and MW-Series helical beam couplings each have two sets of spiral slots, a feature that provides superior parallel misalignment capabilities compared to the single beam coupling. Angular misalignment, axial motion and any combination of all three types of misalignment are also easily accommodated by this flexible coupling. Ruland's clamp style beam couplings have the additional benefit of dynamic balancing, due to the unique configuration of the socket head cap screws.
Helical beam couplings should be used in applications in which misalignment exists between the two shafts being coupled. The F-Series helical couplings are ideal for light duty power transmission applications such as coupling a servo motor to a lead screw in a motion control system. These flexible couplings feature larger body size and stronger beams to provide high torque capacity and very low windup, while not sacrificing misalignment capabilities. The demanding nature of reversing servo applications make the performance benefits delivered by the F-series beam couplings vital to maintaining the accuracy, repeatability and reliability of the system. F-series helical couplings with socket head cap screws include Ruland's exclusive Nypatch® coating. This coating reduces vibration which can cause threads to loosen, and reduces galling of the screw threads in stainless steel shaft couplings.
The P-Series and MW-Series flexible beam couplings are designed specifically for precision applications, especially those that use delicate components such as encoders and tachometers. The small bearings on these components make low radial forces essential to longevity and continued high performance. The P and MW-series helical couplings provide extra flexibility to yield reduced bearing loads. These flexible couplings are shorter than the F-series beam couplings and conform to industry standard lengths, fitting into confined spaces and allowing for easy retrofits in existing equipment. At the same time, the helical cut pattern continues to provide excellent torque capabilities and low wind-up. Ruland beam couplings are an economical choice for servo applications.
The MW-Series differs from the P-series in that all of its dimensions are purely metric.
Learn more about how to choose a helical beam coupling for your particular application from a Ruland expert. Read "What to Look for in a Servo Coupling" written by William Hewitson, Vice President of Operations.
Also, when choosing a flexible coupling, read about the advantages of the F-Series six beam coupling here.