A rotational operation device (1) includes a holder (32) fixed to a rotation shaft (21), a torsion coil spring (42), and a case (13) accommodating the holder (32) and the torsion coil spring (42). The torsion coil spring (42) includes a coil (43), fitted to the rotation shaft (21), and two protrusions (44,45), located at opposite ends of the coil. When the rotation shaft (21) is rotated, the case (13) restricts movement of the first protrusion (44/45), and the holder (32) pushes the second protrusion (45/44) in a rotation direction of the rotation shaft (21). The case (13) includes a first groove (51/53) that receives the first protrusion. The holder (32) includes a second groove (52/54) that receives the second protrusion. The first and second protrusions (44,45) are spaced apart by an invariable interval (L) set by a fixed length (P) between the first and second grooves. The fixed length (P) is set to a distance that produces a gap between coil windings when the torsion coil spring (42) is in a load-free state.
ROTATIONAL OPERATION DEVICE
ROTATIONSBEWEGUNGSVORRICHTUNG
DISPOSITIF DE FONCTIONNEMENT DE ROTATION
04.10.2017
Patent
Elektronische Ressource
Englisch