DE9111018U1 - Suspension device for an observation device - Google Patents

Description

Title: Suspension device for an observation device

Description

The invention relates to a suspension device for an observation device, in particular for a surgical microscope, with a multi-part swivel arm, the individual arms of which are connected to one another via swivel joints and the first free end of which is designed for articulated attachment to a wall or ceiling of a room or a tripod and the second free end of which is designed for attachment of an observation device.

It is often necessary to move and adjust observation devices three-dimensionally in space in order to position the observation device at the most favorable viewing angle. In order to be able to refocus after changing the position of the

To avoid the risk of damage to the microscope, it is necessary that the distance of the observation device from the object point remains unchanged. Surgical microscopes are used in neurosurgery, particularly in brain surgery. For example, channels must be opened through the brain to allow access to the site of a brain tumor. Operations of this type are often carried out under a surgical microscope so that small blood vessels or intact tissue are not damaged. The surgeon must then look at the tumor either through a channel from different angles or alternately through one of several channels through the microscope in order to successfully carry out the treatment on the tumor. Similar tasks also arise in other forms of neurosurgery, e.g. surgery of fine nerve strands in tissue. To ensure that the surgeon has both hands free for his surgical interventions, the suspension for the surgical microscope should be able to be moved quickly and safely in space in order to optimize the viewing direction of the microscope, while maintaining the focus setting.

In practice, a tripod or the wall or ceiling of the operating room is chosen as the mounting location for the suspension device.

The most commonly used stands are mobile floor stands, some of which are equipped with a height-adjustable horizontal arm that can be swiveled 360 degrees. To prevent the weight of the surgical microscope from pulling the horizontal arm downwards, counterweights are provided, which are arranged, for example, in the vertical column. Pedal bolts with brake blocks in the foot section of the stand enable quick and safe locking.

at the installation site. The surgical microscope itself is connected to the horizontal arm via joints and couplings, so that it can be brought into any desired position. The above-mentioned construction allows the axis of the surgical microscope to be rotated over a large angular range by rotating around a mechanical axis in a vertical plane. The disadvantage of these simply constructed stands and suspension devices, however, is that the optical axis of the surgical microscope can only be adjusted in one plane. According to the state of the art, a floor stand is also known in which the microscope is connected to a floor stand via a rod system. The rods enable the transmission of a rotating movement of the microscope around the observation point by shifting the pivot points into the stand unit, which is essentially achieved by spatially acting parallelogram arms. Here, too, balancing weights are used to lock the height, but due to their large masses, they increase the inertia of the moving parts of the suspension device. When moving the microscope, the surgeon must exert a great deal of force to initiate the movement and then slow it down again after adjustment. The parallelogram arms are often disruptive due to their massive construction and must be manufactured with a complex design in order to enable precise adjustment. This often results in a price for the suspension device that exceeds the cost of the actual observation device, in this case the surgical microscope. Mobile stands also often have the disadvantage that they can only be moved with great effort due to their high weight.

Although wall and ceiling mounts have the disadvantage that they fix the work area in a stationary manner, they also have the advantage that they take up less space.

In order to make the working area of a suspension device more variable, it has already been proposed to control suspension devices using robots. The surgical microscope is made to circle by sequentially moving to certain points in space, with the microscope being tilted in such a way that the optical axis of the microscope remains directed towards the observation location. The disadvantages of this system are that it is practically impossible to move the suspension device from the ceiling of an operating room to an adjacent operating room or it can only be achieved with great effort. Another serious disadvantage is that the microscope can no longer be guided by hand, but only by electric drive motors that are operated by remote control levers or foot switches. The movement of the microscope is only possible at the speed limited by the servomotors, so that a rapid swiveling of the observation position, as the operating doctor often needs, is impossible. The cost of an electric motor control is even higher, which further worsens the ratio of the cost of the actual microscope to the cost of the suspension for it.

It is therefore the object of the present invention to create a simple and therefore inexpensive suspension device that is as small and lightweight as possible and has no annoying rods near the microscope itself that could impair the freedom of movement of the operating doctor. In particular, the structure should be such that existing ceiling or floor stands can still be used, so that existing systems can be easily retrofitted. The suspension should also be

Furthermore, it is possible to swivel the observation device on a spherical bowl surface at various, measurable heights, with the object point lying in the circle center of the bowl.

This object is achieved by the suspension device described in claim 1, which is characterized according to the invention in that each arm has a curvature in the longitudinal direction, the radius of which essentially corresponds approximately to the distance of the observation device from the observation point, and that each swivel joint or each articulated fastening has only one rotation or swivel axis, which is essentially directed in the direction of the observation point. The particular advantage of this embodiment is that, compared to the swivel arms known from the prior art, a swivel adjustment is also possible in such a way that the distance to the observation point remains unchanged when the position of the observation device changes. By setting the swivel axes in the direction of the observation point, it is no longer necessary to adjust the microscope after a change in position, in particular a change in height.

Preferably and in the structurally simplest embodiment, two arms of the same length are provided. According to a further embodiment, however, at least one of the arms can be designed as a telescope, whereby the adjustment range can be varied further.

The present invention is based on the following mechanical principle:

An arm suspended from a ceiling unit or a floor unit is pivotally arranged so that the end of the

arm can rotate on the surface of an imaginary sphere, in the center of which the object to be observed is arranged. The arm is designed as a circular arc segment corresponding to a great circle section on the imaginary sphere. The invention also includes such embodiments in which the arm has a different shape, but always its free end, on which a rotation or pivot axis is located, is at the same distance from the center of the sphere and thus the object to be observed as the pivot point at the attachment point on the ceiling or a floor unit. The axis at the free end of the arm is always aligned so that it points to the center point of the imaginary sphere. A second arm rotatably attached to this axis is designed so that the free end of the second arm, when rotating about the axis at the free end of the first arm, moves on the surface of another imaginary sphere, which is concentric to the first imaginary sphere of the first arm and thus has the same center point. The second arm can also be designed as an arc of a great circle on the second imaginary sphere or have any other shape, as long as the free end of the second arm is the same distance from the center of the sphere as the pivot point of the second arm. At the end of the second arm there is another axis of rotation, which is also aligned towards the center of the imaginary sphere. The length of the second arm is chosen so that at one point the directions of the axes at the end of the second arm and at the beginning of the first arm coincide. The microscope or other observation device is connected to the end of the second arm in a rotatable manner.

The swivel joints have spring elements to compensate for the weight. Due to the design,

The suspension device does not have any weight moments around the fastening point on the ceiling or floor unit, which could cause the first arm to fall into a preferred position. However, when the second arm rotates or swivels around the axis of rotation at the end of the first arm, the microscope experiences a height difference which requires compensation of the weight forces in order to ensure that the microscope remains fixed at the desired point in space. This compensation is brought about by spring elements in a simple mechanical manner. Preferably, the spring elements are screws or gas springs, but other spring elements are also possible. The advantage of these spring elements in conjunction with the design described above is that the movement of the observation device, in particular the microscope, is not opposed by any additional mass inertia, which means that, for example, the operating microscope can be quickly brought to the desired location by the operating doctor or nurse with little effort. To simplify handling of the suspension device, the swivel joints and/or the articulated fastenings are equipped with mechanical or motor-operated braking devices.

The two-arm design described in more detail above, in which at least one arm can be designed as a telescope, can also be varied according to a further embodiment of the invention so that the arms or at least one of the arms are designed as parallelogram handlebars or scissors, as long as the essential condition remains fulfilled that each axis of rotation remains directed towards the center of the imaginary sphere, the observation point. For example, the suspension device can be designed as scissors, in which the arms are connected to one another in such a way that

are arranged in such a way that their movement against each other is not hindered and the scissors can be extended in both directions. In other scissor-like designs, two units are arranged next to each other, with the axes in front of the attachment point on the support unit and/or for the microscope suspension being mounted eccentrically and at the same distance on both sides of a common central axis in a support piece.

In order to achieve smooth and robust suspension, the articulated fastenings or swivel joints are preferably designed as rolling bearings.

A further reduction in the mass inertia of the suspension device is preferably achieved by the arms being made of metal or plastic, in particular by having a lightweight construction. According to a further embodiment of the invention, this can consist of hollow profiles or composite materials, preferably with a honeycomb structure. Such lightweight constructions are known in principle in other technical areas, such as aircraft construction.

The simple construction and lightweight design of the suspension device allows for easy conversion or retrofitting of existing tripods on ceilings, walls or floor frames. In particular, the suspension device can also be easily dismantled and quickly installed in another room or on another local tripod attachment.

Embodiments of the invention are shown in the drawings. They show

Fig. 1a to 1d a suspension device with two arms that can rotate against each other in different swivel positions,

Fig. 2a and 2b show in principle the geometric locations to which each of the arms can be adjusted, and

Fig. 3 a modification of the hanging device in the form of scissors.

The suspension device according to Fig. 1a to 1d consists essentially of two arms 10 and 11, each of which has a curvature in the longitudinal direction, the radius of which essentially corresponds approximately to the distance of the observation device from the observation point. The first arm 10 is attached in a rotatable manner via a swivel joint 12, for example to the ceiling of a room. The axis of rotation of the joint 12 is directed towards the observation point. At the end of the first arm 10 there is another swivel joint 14, to which the second arm 11 is attached. This swivel joint is also aligned so that the axis of rotation points towards the observation point. At the free end of the second arm 11 there is a fastening 13 for a surgical microscope. The axis of this swivel fastening also points towards the observation point.

Fig. 1b shows the same arrangement as Fig. 1a with the difference that the second arm 11 has been pivoted relative to the first arm 10 in the direction of arrow 15. In the position shown in Fig. 1c, both the arm 10 (see arrow 16) and the arm 11 (see arrow 17) are pivoted. Fig. 1d shows the maximum design of the two arms 10 and 11, whose longitudinal axes (apart from a slight height offset and the curvature) lie on a straight line.

The movement locations of the two-arm suspension device according to F i g.1 can be seen from Fig. 2a and 2b. Fig. 2a shows in schematic form only the first arm 10, which lies on an imaginary sphere 18, in the center of which M is the object to be observed. The arm 10 can be rotated by 360 around the axis defined by the attachment point 12, whereby the free end of the arm 10 with its end-side swivel joint 14 can assume any position on the circular arc 19. This circular arc is part of the imaginary sphere 18. The second arm 11 can also be rotated by 360 around the axis defined by the swivel joint 14, which is shown in a sketch in Fig. 2b. The end section of the second arm 11, which determines the attachment location 13, can be moved along a circle 20. This movement of the second arm 11 on a non-horizontal circular arc enables the height of the observation device to be adjusted. In order to prevent the weight of the second arm 11 and the observation device from causing the second arm to fall into the lowest position (position of lowest potential energy), the swivel joint 14 is equipped with spring elements to compensate for the weight. If telescopic arms are used instead of rigid, length-invariant arms 10 and 11, adjustment locations for the observation device can also be created outside of a fixed sphere 18, as long as the focusing area is not left. Instead of two arms 10 and 11, four, six or eight arms can also be arranged on different circles of the spherical shell. This allows the length of each arm to be reduced, so that a more compact unit is created that can be pushed together into a small space.

A further variant is indicated in Fig. 3. In a double parallelogram arrangement, arms

21 to 2 3 and 24 to 26 are arranged in a scissor-like manner, with the arms 21 and 24 replacing the arm 10 according to Fig. 1c and the arms 22 and 25 replacing the arm 11, so that due to the scissor-like connection of the arms by joints, a length adjustment
the device is possible. The above applies to the alignment of the rotary or swivel joints 12 to 14, ie
the extended axes of rotation intersect at the observation point M.

Claims (12)

Protection claims: 1. Suspension device for an observation device, in particular for a surgical microscope, with a multi-part pivot arm, the individual arms of which are connected to one another via pivot joints and the first free end of which is designed for articulated attachment to a wall or ceiling of a room or a tripod and the second free end of which is designed for attachment of the observation device, characterized in that each arm (10, 11; 21 to 24, 25 to 28) has a curvature in the longitudinal direction, the radius of which essentially corresponds approximately to the distance of the observation device from the observation point (M) and that each pivot joint (14) or each articulated attachment (12, 13) has only one rotation or pivot axis, which is directed essentially in the direction of the observation point (M). 2. Suspension device according to claim 1, characterized in that two arms (10, 11) of the same arc length are provided. 3. Suspension device according to claim 1, characterized in that at least one of the arms (12, 11) is designed as a telescope. 4. Suspension device according to one of claims 1 to 3, characterized in that the swivel joints (14) have spring elements for weight compensation. 5. Suspension device according to claim 4, characterized in that the spring elements are screws or gas springs. 6. Suspension device according to one of claims 1 to 5, characterized in that the pivot joints (14) and/or the articulated fastenings (12, 13) have mechanical or motor-operated braking devices. 7. Suspension device according to one of claims 1 to 6, characterized in that the arms or at least one of the arms is or is designed as a parallogram link or scissors (21 to 28). 8. Suspension device according to claim 7, characterized in that the shear axes of the arms have a common central axis directed towards the observation point (M). 9. Suspension device according to one of claims 1 to 8, characterized in that the articulated fastenings (12, 13) or the swivel joints (14) are designed as roller bearings. 10. Suspension device according to one of claims 1 to 9, characterized in that the arms (10, 11; 21 to 28) are made of metal or plastic. 11. Suspension device according to claim 10, characterized in that the arms (10, 11, 21 to 28) are of lightweight construction using lightweight material, such as aluminum or the like. 12. Suspension device according to claim 11, characterized in that the arms (10, 11, 21 to 28) consist essentially of hollow profiles or composite materials, preferably with a honeycomb structure.