Patent ID: 8416492

Claim:
A balancing apparatus for a surgical microscope for balancing an optics carrier that carries optics of the surgical microscope, said optics carrier being held via a pivot support at a stand such that the balancing compensates for the use with and without a microscope holder holding the surgical microscope and with and without add-on units, wherein the balancing apparatus is arranged at the free end of the pivot support and comprises: a Y displacement unit comprising a first slide for displacement of the optics carrier in a Y direction, the first slide being driven by a remotely controllable first motor; a Z displacement unit comprising a second slide for displacement of the optics carrier in a Z direction by a second motor; a selector switch enabling an operator to select powering either the first motor or the second motor; and a forward-reverse switch enabling an operator to select either the forward or the reverse driving mode for the motor powered by the selector switch and consequently enabling the operator to select either the forward or the reverse driving mode of the first or second slide, respectively; wherein the first and second slides are integrated into a cross-slide that is rotatable around a rotation axis relative to the pivot support, wherein the first slide is arranged as part of the Y displacement unit transversely to the rotation axis alongside the pivot support and the second slide is arranged between the first slide and the optics carrier as part of the Z displacement unit, so that the weight of the second slide acts as a compensation weight across the rotation axis for locating a common center of gravity G of the optics carrier with respective accessories and the Y and Z displacement units in the rotation axis; and the first slide of the cross-slide has a first guidance element and a first insert axially displaceable in that first guidance element, the first insert is secured to a second guidance element of the second slide, the second guidance element has a second insert arranged axially displaceably in said second guidance element, and the insert of the second slide is connected to the optics carrier.