Patent attributes
A surgical head clamp is provided including an essentially U-shaped retaining clip (1) with two holder arms (3, 4), running towards the same side in the plane thereof at the ends of a connecting bar (2). The arm ends (5, 6) of the holder arms have mandrel holders (11) mounted adjustably in bearings that are coaxial to one another. The mandrel holders may be provided with one or more said holding mandrels (12), whereby a first mandrel holder is pivotably fastened at a bearing part (15) of the one arm end (6), which bearing part is adjustable around a common bearing shaft (9), and a second mandrel holder (11) can be adjusted by means of a threaded spindle (10) in a bearing bore (7) of the other said arm end (5). The second mandrel holder (11) includes a guide shank (50) that is provided with a socket bore (54) on the front side, which is mounted coaxially to the bearing shaft (9) in a spring-mounted manner in a axial bore (61) of the threaded spindle (10). The threaded spindle (10) is provided with an external thread and is adjustably mounted in a smooth cylindrical bearing bore (7) of the other arm end (3). The external thread is embodied as a ball thread (23), which has an arcuate-segment profile, with which two balls (24, 25) mesh as contact elements. The balls are arranged in a diametrically opposed, axially fixed manner in the wall (28) of the bearing bore (7) and are held in contact with the ball thread (23) by an adjustable locking lever (35) in the locked position thereof, and which can be brought out of contact with the threaded spindle (10) in another position in order to make the threaded spindle (10) freely displaceable in its said bearing bore (7).
