Patent ID: 7472872

Claim:
A weight balancing mechanism for a stand supporting an operation microscope, comprising: a first parallel linkage being supported on a first rotation axis which is fixed relative to a stand body; a distal link being supported on a second rotation axis which is fixed relative to a first horizontal link element of the first parallel linkage; a second parallel linkage being supported on a third rotation axis which is fixed relative to the distal link, and an operation microscope being suspended from and supported by the third rotation axis via the second parallel linkage; a counterweight being fixed relative to a second horizontal link element of the first parallel linkage, on the side opposite to the distal link with respect to the first rotation axis; a first control mechanism configured to produce a first weight balance about the first rotation axis for the first parallel linkage by using the counterweight; a second control mechanism configured to produce a second weight balance about the third rotation axis for the second parallel linkage; a first switch controlling an operation of the first control mechanism and the second control mechanism; and a second switch controlling only an operation of the second control mechanism; wherein, the second parallel linkage defines an operating space; and the second switch is located above the operating space.