Editing Coupling (section)

=== Beam ===
[[File:Beam Coupling - Helical Standard.jpg|thumb|A beam coupling]]
A ''beam'' coupling, also known as ''helical'' coupling, is a flexible coupling for transmitting torque between two shafts while allowing for angular misalignment, parallel offset and even axial motion, of one shaft relative to the other.  This design utilizes a single piece of material and becomes flexible by removal of material along a spiral path resulting in a curved flexible beam of helical shape.  Since it is made from a single piece of material, the beam style coupling does not exhibit the [[Backlash (engineering)|backlash]] found in some multi-piece couplings. Another advantage of being an all machined coupling is the possibility to incorporate features into the final product while still keeping the single piece's integrity.

Changes to the lead of the helical beam provide changes to misalignment capabilities as well as other performance characteristics such as torque capacity and torsional stiffness.  It is even possible to have multiple starts within the same helix.

The material used to manufacture the beam coupling also affects its performance and suitability for specific applications such as food, medical and aerospace. Materials are typically aluminum alloy and stainless steel, but they can also be made in [[polyoxymethylene|acetal]], [[maraging steel]] and [[titanium]]. The most common applications are attaching [[rotary encoder]]s to shafts and motion control for [[robotics]].

Beam couplings can be known by various names depending upon industry. These names include flexible coupling, flexible beam coupling, flexible shaft coupling, flexure, helical coupling, and shaft coupling.

The primary benefit to using a flexible beam coupling to join two rotating shafts is to reducing vibration and reaction loads which in turn will reduce overall wear and tear on machinery and prolong equipment life.

<gallery mode=packed>
File:Special Beam Couplings with attachments.jpg|A beam coupling with optional features machined into it
File:Helical U-Joint (Beam Style Coupling) - Angular Misalignment.jpg|Increasing number of coils allows for greater angular misalignment.
</gallery>