Blog Rollon: Designing Together

Telescopic Linear Bearings Help Tray Tables Enhance Passenger Convenience and Comfort

Written by x | Nov 4, 2020 11:00:00 PM

Choosing the right motion device for a high-performance airline tray table is no easy task. While many linear bearings are available for tray tables that require only basic, jerky motion for economy-class seating, rail systems for first-class and business-class seats — which are typically designed to recline or even lie flat — must satisfy a long list of criteria. And passengers expect smooth, quiet motion from their tray table.

Here are some typical challenges designers must consider when selecting linear bearings for premium-tier seats aboard an airplane:

  • Build a lightweight table with high load capacity. The airline industry’s insatiable need for lighter airplanes means seat trays must support heavy loads while weighing as little as possible.
  • Long stroke lengths. Reclining and lie-flat seats demand linear rails that offer long extensions without excessive deflections that could otherwise hinder tray table functionality. 
  • Mitigate deflection. Although static load demands in normal operations for tray tables can be quite low, high stiffness is still crucial to ensure the tray table performs as needed, especially at full extension.
  • Smooth, quiet operation. Passengers should not notice linear guides when they maneuver their seat trays. 
  • Long lifetime. Linear bearings for tray tables must operate over tens of thousands of cycles despite the beating that tray tables typically endure. 
  • Withstand abuse. Not only must the tray table be designed to meet the airline’s specifications, the Federal Aviation Administration (FAA) calls for tray tables to meet “abuse loads” — specific weight and force requirements that will mimic deformations or other stresses a tray table must withstand yet still fully retract in case of an emergency. A catastrophic failure resulting in broken or fractured parts is not permitted.

 


The Right Balance of Capabilities to Support Tray Table Demands

When designing tray tables for premium-class airplane seating, be sure to choose a telescoping linear bearing that balances heavy-duty load carrying capabilities with a sturdy, yet lightweight profile. Rollon’s Telescopic Rail family with caged ball bearings is made from high-strength carbon steel to handle heavy loads with good stiffness and minimal deflection — even at full extension. The series’ I-beam shape with a stiff cross section gives it a weight-reduced design with excellent rigidity. Induction hardened and ground raceways provide smooth, consistent movement when vibration, impact or shock loads occur. These characteristics provide long lifetimes of 50,000 cycles and more, depending on various design factors. Additional features include: 

  • Partial, full and 150% telescopic strokes in various bearing sizes and intermediate elements.
  • Smooth movement and soft end stops for quiet operation.
  • Controlled friction keeps the tray table in position during airplane maneuvers, turbulence and vibrations.
  • Customized weight reduction features tailored to the application requirements.


Telescopic Rails can be customized to satisfy abuse load requirements so the tray table can be stowed away even when deformed in an emergency. Rollon can also provide the right amount of mounting holes along with special locking devices to secure fasteners and make installation easy. Rollon can produce special versions and strokes upon request, so be sure to provide a Rollon product specialist your requirements for stroke length, load handling and life cycles as well as your tray table dimensions and other motion needs such as pivot or hinge elements. 


Tray Tables That Sit Well With Passengers 

When designing airplane seat tray tables, many linear bearings can fit the bill. Most can provide basic motion for economy-type seat tray tables, but first- and business-class type seats demand a higher performance telescoping linear bearing that can move heavier loads smoothly and quietly. Rollon’s Telescopic Rail family of linear bearings is designed to handle heavy loads at long extensions with minimal deflection so passengers can enjoy extra convenience and comfort throughout the flight.


For more information about Rollon’s Telescopic Rail family of linear bearings