Electric portable power tool with rotatable guard

A manually operated electric machine tool for a disk-shaped rotating tool (18), comprising:

• a machine housing (11), wherein a drive spindle (12) for the tool (18) protrudes from the machine housing (11);
• a guard (20) that is detachably connected to the machine housing (11) and is designed to at least partially cover the tool (18), wherein said guard has a clamp (23) with a clamping element (24);
• and
• a hollow cylindrical collar (15), wherein said collar is provided on the machine housing (11) and is coaxial to the drive spindle (12), the clamp (23) permitting the guard (20) to be mounted onto the collar and fixed in relation to the collar it,
• wherein the clamp (23) is secured to the collar (15) in a rotating fashion and a manually releasable locking mechanism between the clamp (23) and the collar (15) is designed so as to permit the guard (20) to be locked in a number of definite relative rotational positions in relation to the collar (15),
• wherein the manually releasable locking mechanism has a toothed section (34) provided on the collar (15) and a ratchet (37) that is provided on the clamp (23) and is pressed into the toothed section (34) by means of spring force, and
• wherein the ratchet (37) is embodied on a soring-loaded hand lever (36) that is provided on the outside of the clamp (23) and is able to pivot around a pivot axis (361) parallel to a clamp axis.