Stand, in particular for surgical microscopes, having an energy storage element

1. A stand for a surgical microscope, the stand comprising:

a vertical support having a vertical longitudinal axis;

a horizontal support articulated on the vertical support;

an energy storage element that is articulated at a proximal articulation point adjacent the vertical support and at a distal articulation point adjacent the horizontal support;

an articulation element ( 21 ) adjustably positionable relative to the vertical support, the articulation element having a guide ( 19 ) defining a generally vertical guide path;

a carriage ( 16 ) engaging the guide ( 19 ) for travel along the guide path, the proximal articulation point being coupled to the carriage for travel therewith;

a first displacement apparatus ( 18 b ) operable to displace the articulation element ( 21 ) relative to the vertical support to shift the proximal articulation point along a generally horizontal path; and

a second displacement apparatus ( 18 c ) operable to displace the carriage along the guide path to shift the proximal articulation point along a generally vertical path.

2. The stand as defined in claim 1 , wherein the generally vertical path is an arcuate path.

3. The stand as defined in claim 1 , wherein the first displacement apparatus is operable to displace the proximal articulation point along an arc about a rotation point ( 22 a ) while the rotation point is fixed relative to the vertical support.

4. The stand as defined in claim 3 , wherein the rotation point is arranged on a plate connected to a side of the vertical support.

5. The stand as defined in claim 3 , wherein the first displacement apparatus is operable to displace the proximal articulation point along an axis approximately parallel to the horizontal support.

6. The stand as defined in claim 5 , further comprising a first plate fixed to the vertical support and a second plate mounted on the first plate for guided adjustment along the axis approximately parallel to the horizontal support, wherein the rotation point is arranged on the second plate.

7. The stand as defined in claim 6 , wherein the articulation element is pivotally mounted on the second plate at the rotation point, a releasable mount is provided at a location spaced from the rotation point for selectively securing the articulation element against rotation about the rotation point, and the first displacement apparatus includes a spindle arranged to engage the articulation element at a location spaced from the rotation point.

8. A method for adjusting a proximal articulation point ( 9 ) of an energy storage element ( 7 ) in conjunction with a surgical microscope stand having a vertical support ( 2 ), a horizontal support ( 4 ) articulated on the vertical support, the stand being subjected to a weight torque (M G ) about an articulation point of the horizontal support, a support torque (M F ) generated by the energy storage element ( 7 ) about the articulation point of the horizontal support, the energy storage element ( 7 ) being articulated with its proximal articulation point ( 9 ) associated with the vertical support ( 2 ) and with its distal articulation point ( 10 ) associated with the horizontal support ( 4 ), and the horizontal support having a pivot angle range of movement about its articulation point between a minimum pivot angle (αmin) and a maximum pivot angle (αmax) or between a maximum negative pivot angle (−αmax) and a maximum positive pivot angle (+αmax), the method comprising the steps of:

ascertaining a first position for the proximal articulation point, corresponding to which first position there is a specific pivot angle range (α 1 -α 2 or α min -α 3 ) in which the torque difference (ΔM) between the weight torque (M G ) and the support torque (M F ) is zero or most minimal;

then, proceeding therefrom, ascertaining a second position for the proximal articulation point, corresponding to which second position there is a minimal torque difference (ΔM) over the entire pivot angle range (α min to α max or −α max to +α max ); and

fixing the proximal articulation point at the second position.