Finger Mechanism with Ball Screw782436:001.26
Robust and strong like the human hand
A leading manufacturer of prostheses contacted us with the task of manufacturing a mechanism that would be used in an artificial hand. In close cooperation with the customer, we developed a ball screw drive integrated in the support structure. Due to miniaturization, the threaded drive as well as the associated pressure bearing had to be adapted. The recirculating ball nut is designed as a thrust piece, which avoids additional parts with narrow tolerances for functional integration. The pressure bearing for absorbing the considerable axial forces was manufactured with a reinforced outer ring to allow installation without a completely enclosing support structure. All parts are made of stainless steel. This is the only way to withstand the peak forces incurred in using a hand.
Series production by means of run-in stand
The drive is coupled in via a beveled wheel, which is not shown here. Series production is supported by devices for assembly and a run-in stand. The first 1000 full strokes are executed on the run-in stand in order to ensure very even running behavior even with a rearward-acting force (finger is moved by external forces). After the run-in, the unit is cleaned again and provided with a lifetime lubrication.