ROTATION UNIT, ROCK DRILLING UNIT AND METHOD FOR ROCK DRILLING

摘要

Abstract The invention relates to a rotation unit, rock drilling unit and method for rock drilling. The rotation unit (7) comprises a main shaft (17) that is rotated around its longitudinal axis by means of a rotating motor (22). The main shaft comprises a tubular outer shaft (18) and an inner shaft (19) arranged inside the outer shaft. The outer shaft is supported to a body of the rotation unit and is configured to transmit axial forces, whereas the inner shaft is configured to transmit rotation and torque. (Figure 3) (o co 00- c)