Just sit back and relax

Aircraft seating has to look welcoming. It must be comfortable and very easy to operate. To allow flying to be more economic and thus also more ecologically-friendly, the design has to focus not just on seating comfort and functionality but also on weight, space-saving, service life and quality. Up till now, the adjustment of the back-rests, seats and foot rests in aircraft seats has always been done by three separate mechanisms. With the new adjustment system they are all controlled from a single central point, using three small, highly-precise and robust Carry type ball screws.
A particular design challenge was posed by the 10 highly-accurate drill holes (ø 1.52 mm) on the ball screw nuts, which are essential for motor power transmission. Metal lives. Just how "living" steel is can be seen very clearly during the hardening process. The metal changes in various ways depend on the heat applied and it loses size accuracy. These changes cannot be computed or predicted. After successive cycles of measuring and hardening, the Eichenberger developers succeeded in adjusting the drill holes to the required size. After vacuum hardening, the dimensions of the high precision drilling met the specifications with ± 0.015 mm tolerance. The nuts were hardened to 59-63 HRC. Due to the excellent, close working relationship with the heat treatment plant, prototypes can be manufactured quickly and flexibly. Thanks to its smart, production processes, Eichenberger is in a position to respond to customer requests at very short notice.
Service life calculations can be performed immediately and modifications to the production process are always possible.

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