Stand, in particular for surgical microscopes

Supports – Stand and bracket – Having adjustable bracket

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C248S162100, C248S280110

Reexamination Certificate

active

06708936

ABSTRACT:

CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority under 35 U.S.C. 119 of German Patent Application No. DE 200 19 109.8 filed Nov. 12, 2000.
The complete disclosures of the following three copending, commonly-owned U.S. patent applications filed concurrently with the present application are hereby incorporated by reference into the present specification: U.S. patent application Ser. No. 10/008285 (Attorney Reference LAGP:109_US_; corresponds to German Application No. 200 19 106.3 filed Nov. 12, 2000); U.S. patent application Ser. No. 10/007168 (Attorney Reference LAGP:110_US_, corresponds to German Application No. 200 19 107.1 filed Nov. 12, 2000); and U.S. patent application Ser. No. 10/010101 (Attorney Reference LAGP:111_US_; corresponds to German Application No. DE 200 19 105.5 filed Nov. 12, 2000).
FIELD OF THE INVENTION
The invention relates to a stand, more particularly to a stand for a surgical microscope which compensates for the weight of the microscope and any additional devices.
BACKGROUND OF THE INVENTION
It must be easy for surgical microscopes to be able to pivot over a wide, prescribed range. In addition, once a surgical microscope is properly positioned, the microscope stand should be capable of easily holding a microscope in the desired position. For this reason, microscope stands are provided with balance weights which compensate for the weight of the microscope and any additional devices. The balance weights are frequently arranged in the manner of beam-type balances. Particular embodiments of such beam-type balance arrangements are, for example, the “OHS™” design, in which balance weights are displaced from top to bottom via parallelogram carriers such that the overall centroid of the stand is situated in the lower region of the stand structure. The design principle of the OHS™ is illustrated symbolically in the International Patent Application WO 97/13997.
A further design, “MS 1” provides a balance device for ease of operability of the microscope and movability of the latter in space. This balance device also provides for the relevant compensation of changes in the weight of the microscope; adding or removing additional devices on the microscope is conducted via a pressure spring, which is clamped obliquely or diagonally in a parallelogram carrier. This parallelogram carrier serves as a pivotable horizontal carrier for the microscope. In the International Patent Application No. WO 99/1693 (Bees), the design of the MS
1
is illustrated symbolically and the particular parallelogram carrier design has been published in European Patent Application No. EP 433426 A1 (WO 91/472).
For the purpose of improved tilt stability, MS
1
provides a switchbox which contains the electric power supply for the microscope, its illuminating device, its controllers or the like and, if appropriate, any additional weight. The switchbox is mounted rigidly on the vertical support column of the stand and undertakes there only balancing over the vertical axis of the upright support column with regard to improving the tilting moment of the stand.
DE 19742050 A1 refers to an article “Gewichtsausgleich an feinmechanischen Geräten” [“Balancing on fine-mechanical equipment”], which was published by Hilpert in No. 2/1965 of the journal Feingerätetechnik, Volume 14. In this article from 1965, there is a detailed discussion of various weight-compensating measures in fine mechanics, which are achieved principally not by a counterweight, but by spring-compensating measures (such as, by way of comparison, only in the case of the MS
1
design).
DD 221571 A1 (1985) describes a stand design having a lever arm, which is weight-compensated by the spring which is connected to the lever arm via a cable pull. The surgical microscope is located at the distal end of the lever arm. The fundamental adjustment of this surgical microscope is performed via a threaded spindle which is used to draw the end of the spring fixed to the housing further from the lever arm, or to guide it nearer to it. Changes in weight at the microscope are compensated by the fact that the pivoting point of the cable pull is adjusted relative to the lever arm via a spindle. In order to achieve a uniform countermoment in all possible angular positions, it is necessary for the abovementioned point of action of the cable pull to be located on a connecting line between the axis of rotation of the lever arm and the centroid of the microscope. This is achieved by actuating an adjusting device in the form of a worm gear, which rotates a disc, connected to the lever arm, about the axis of rotation of the lever arm. This design requires a great number of adjusting measures in order to achieve the desired effect. In this case, the disc-worm design prevents, independently of the weight, the possibility of selecting any desired position of the microscope. Apart from this, the construction of this known design necessitates a high overall centroid of the stand, since all the balancing devices are arranged above the microscope.
DE 3739080 A1 (1989), likewise, specifies a spring device for balancing stands where cable pulls combined with springs are intended to lead to balancing. However, this publication discloses forcing support and adjustable movement which is exercised by an operator on a handle. This patent does not teach holding a load in a counterbalanced “floating state” as is desired when using a surgical microscope.
By contrast, U.S. Pat. No. 5,397,323 (1992) presents a surgical robot having parallelogram carriers, in the case of which, inter alia, the weight of the instrument is held in a weight-compensated fashion via a cable pull with the aid of a counterweight. The cable pull is of closed design in this case, that is to say that one cable in each case is guided from the instrument up to the counterweight over an upper and lower deflecting roller (FIG. 3 of U.S. Pat. No. 5,397,323). Such a design presupposes that the counterweight is attached in the immediate vicinity of the instrument. It could therefore be applied only poorly for use on a surgical microscope. Its technical teaching is therefore not obvious for adaptation to a stand for microscopes.
Stands without a pivoting arm but with balancing by means of tape pulls over a single deflecting roller directly on the support column were marketed under the designation “Standard” and “Universal”. However, these had no pivoting arm, and the balancing is limited to equalizing the vertical load of the support arm directly on the support column. The tapes which transmitted the force run exclusively parallel to and immediately next to the support column. They act not on the support arm, but on a ring directly on the support column, which held the laterally projecting support arm. In the event of a change in load, it is necessary to change the balance weight if proper balance is desired.
DE 19742050 A1 (1999) discloses a stand design having a pivotable parallelogram carrier which is weight-compensated via a cable pull and a balancing spring such that the additionally present balance weights, which act in accordance with the abovementioned principle of the balance, can be designed to be particularly small. In this design, the cable pull is guided in a special way in order to minimize the balancing error, caused by the finite deflecting radius, in a wide pivoting range. The balancing error is, however, not eliminated by this measure, and so in specific pivoting positions it remains necessary to adjust the balance weights.
U.S. Pat. No. 6,070,839 (2000) discloses a further design having a pivoting arm and a cable pull-spring structure which permits pure balancing (in the sense of the abovementioned balancing with a diagonal bearing spring) but also without contributing balancing moments to an improvement in the tilt stability. In the case of changes in weight, the pivoting point of the cable pull is displaced, in a fashion comparable to the design in the abovementioned DD 221571, over a spindle.
U.S. Pat. No. 5,253,832 (1999) describes a stand having a

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Stand, in particular for surgical microscopes does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Stand, in particular for surgical microscopes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stand, in particular for surgical microscopes will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3223055

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.