EP3856113B1 - Table column for an operating table having a reinforcing mechanism for a cylindrical guide - Google Patents

Description

technical field

The present disclosure relates to table columns for operating tables.

Background to the Revelation

Table columns for operating tables are previously known. They usually include a height-adjustable column head, a patient support surface arranged on an upper end of the column head, and a column base for placing the table column on the floor of an operating room. Such a table column is out DE102016125800 known.

Before and during an operation, the patient support surface must be brought into a position that facilitates an intervention on the patient. The height of the patient support surface should be adjustable over as wide a range as possible. In addition, it may be necessary to pivot the patient support surface through large angles about a tilt axis and a tilt axis in order to fine-tune the patient support position.

A patient support surface of an operating table aligned in this way must remain stable in the desired position. For this purpose, the use of various stability systems to increase the stability of the height-adjustable column head is known.

Despite the known stability systems, however, there is often a small amount of residual play in the direction of rotation of the height-adjustable column head about its vertical axis.

Such play results in a slight wobbling of the patient support surface. Depending on the type of surgical intervention to be performed, this minimal Instability can prove enormously disruptive. A sudden, slight wobbling of the patient support surface and thus of the patient can impair the surgeon's work. This creates a risk for the patient.

For example, in cranial and brain operations using special instruments attached to the operating table, there is a great need for a particularly stable and rigid table column. In particular, the residual play just described is unacceptable in such an application.

Summary of Revelation

An object of the present disclosure is to provide an adjustable table column whose stability and rigidity against twisting about its vertical axis is increased.

• einen Säulenkopfträger;
• einen Säulenkopf, der im Säulenkopfträger aufgenommen und im Verhältnis zu diesem höhenverstellbar ist;
• einen Hubantrieb zur Verstellung der Höhe des Säulenkopfs im Verhältnis zum Säulenkopfträger; und
• eine zylindrische Führung, die den Säulenkopf mit dem Säulenkopfträger verbindet und zur senkrechten Führung des Säulenkopfs bei dessen Höhenverstellung dient,

• wobei die zylindrische Führung eine Längsnut und zwei darin eingreifende Passfedern aufweist, um die zylindrische Führung gegen ein Verdrehen um ihre senkrechte Achse zu sichern,
• wobei jede Passfeder einen Hauptkörper und ein entlang einer Eingriffsrichtung hervorstehendes Eingriffselement umfasst, welches in Eingriffsrichtung in die Längsnut eingreift, und
• wobei die Eingriffselemente der beiden Passfedern quer zur Längsachse der Längsnut versetzt zueinander angeordnet sind, sodass eine Vorspannung in der zylindrischen Führung quer zur Längsachse der Längsnut erzeugt wird.

According to the present disclosure, this object is achieved with a table column for an operating table, which has at least one of the following features:

• a pillar head support;
• a pillar head received in the pillar head support and adjustable in height relative thereto;
• a lift drive for adjusting the height of the column head in relation to the column head support; and
• a cylindrical guide that connects the column head to the column head support and serves to vertically guide the column head when adjusting its height,

• wherein the cylindrical guide has a longitudinal groove and two feather keys engaging therein in order to secure the cylindrical guide against rotation about its vertical axis,
• each key includes a main body and an engaging member protruding along an engaging direction, which engages with the longitudinal groove in the engaging direction, and
• wherein the engagement elements of the two feather keys are arranged offset to one another transversely to the longitudinal axis of the longitudinal groove, so that a pretension is generated in the cylindrical guide transversely to the longitudinal axis of the longitudinal groove.

Due to the special design of the present table column with a column head, a column head support and a cylindrical guide comprising two feather keys, which connects the column head with the column head support and serves to vertically guide the column head when adjusting its height, even a small amount of torsional play in the direction of rotation about a vertical axis is avoided of the table column eliminated.

More precisely, any torsional play is prevented by the special offset arrangement of the engagement elements formed on the feather keys.

The offset of the two engaging elements can consist in that at least one of the engaging elements is arranged eccentrically on its main body.

The offset of the two engagement elements can also exist in that the main bodies assigned to the engagement elements are arranged offset to one another on the column head support.

The engagement elements can be wedge-shaped.

The feather keys can be arranged vertically one above the other along the longitudinal axis of the longitudinal groove.

Each feather key (26) can be assigned a readjustment device for automatic readjustment of its seat within the longitudinal groove.

The readjustment device can be designed to be operated by spring force.

It may also include a set of disc springs. In addition, each readjustment device can have an adjusting screw for adjusting the spring force.

The feather keys can be embedded in holes in the column head beam.

The cylindrical guide may include a central unpowered lift cylinder. The lift cylinder may be passively telescoping to follow the movement of the column head as it is elevated. The table column can also include at least one lifting cylinder that can be driven by means of a lifting drive.

The table column according to the disclosure can also comprise a connection unit arranged at an upper end of the table column. The connection unit can be used to connect a patient support surface to the table column.

In addition, the table column can have a plurality of lifting cylinders, it being possible for the cylindrical guide and the lifting cylinders to be connected to the connection unit by means of articulated connections.

The cylindrical guide and the lifting cylinders can be designed to incline the connection unit about a longitudinal axis of the patient support surface and to cant about an axis running transversely to the longitudinal axis of the patient support surface.

The present table column can further comprise a main lifting device which is telescopically adjustable by means of a drive. The main lifting device can be designed to move vertically the column head support and the cylindrical guide connected to it.

The feather keys can be embedded in the column head beam. The engagement elements of the feather keys can be prestressed in the longitudinal groove by means of spring force. In addition, the longitudinal groove can be designed to slide over the engagement elements of the feather keys.

The main bodies of the present keys can be arranged in the pillar head beam. The longitudinal groove can be designed as a groove extending vertically in the central lifting cylinder of the column head. The longitudinal groove can be used when adjusting the height of the Slide the head of the column vertically in relation to the head of the column using the engaging elements of the keys.

The present disclosure also relates to operating tables with the table column defined above, and their use in surgical interventions.

Brief description of the drawings

Fig. 1

einen Überblick über einen Operationstisch mit einer Operationstischsäule gemäß der vorliegenden Offenbarung;

Fig. 2

eine perspektivische Ansicht der Operationstischsäule aus Fig. 1 ohne Abdeckung mit einem Säulenschaft und einer Anbindungseinheit für eine Patientenlagerfläche;

Fig. 3

eine perspektivische Seitenansicht der Tischsäule aus Fig. 2 samt einer zylindrischen Führung mit zwei Passfedern und einer Nut;

Fig. 4

eine Längsschnittdarstellung eines Abschnitts der zylindrischen Führung entlang der Linie I-I in Fig. 3;

Fig. 5

eine perspektivische Ansicht eines Abschnitts der zylindrischen Führung aus Fig. 3 und 4 mit einer Querschnittdarstellung einer der beiden Passfedern längs der Linie II-II aus Fig. 3;

Fig. 6

eine weitere perspektivische Ansicht der zylindrischen Führung aus Fig. 3-5 mit einer Querschnittdarstellung einer zweiten Passfeder längs der Linie III-III aus Fig. 3;

Fig. 7

ein Ausschnitt eines Querschnitts durch einen Säulenkopfträger der Tischsäule aus Fig. 2 mit einem darin angeordneten zentralen Zylinder samt einer Bohrung zur Aufnahme einer Passfeder.

Exemplary embodiments of the present disclosure are explained in more detail below with reference to the figures. Show in it:

1

an overview of an operating table with an operating table column according to the present disclosure;

2

a perspective view of the operating table column 1 without a cover with a column shaft and a connection unit for a patient support surface;

3

a perspective side view of the table column 2 along with a cylindrical guide with two keys and a groove;

4

a longitudinal sectional view of a portion of the cylindrical guide along the line II in 3 ;

figure 5

Figure 12 shows a perspective view of a portion of the cylindrical guide 3 and 4 with a cross-section of one of the two keys along the line II-II 3 ;

6

Another perspective view of the cylindrical guide Figures 3-5 with a cross-sectional view of a second key along the line III-III 3 ;

7

a section of a cross section through a column head support of the table column 2 with a central cylinder arranged therein and including a bore for receiving a feather key.

Detailed description

In the following description, exemplary embodiments of the present disclosure are described with reference to the drawings. The drawings are not necessarily true to scale, but are only intended to schematically illustrate the respective features.

It should be noted that the features and components described below can each be combined with one another, regardless of whether they have been described in connection with a single embodiment. The combination of features in the respective embodiments only serves to illustrate the basic structure and the mode of operation of the claimed device.

1 shows an operating table 38 according to the disclosure. This operating table 38 is used for a wide variety of surgical procedures. For this purpose, the patient to be operated on is positioned on the operating table 38 .

The operating table 38 comprises, from bottom to top, a base 39, an operating table column 1 and a patient support surface 40. The operating table column 1 sits on the base 39. The patient support surface 40 is detachably attached to the table column 1.

The height H of the operating table column 1 can be adjusted. Your internal mechanism is protected by a cover 41.

The patient support surface 40 can be pivoted about a tilting axis KK and a tilting axis NN. The patient support surface 40 has a modular structure and can be used in any way expandable. It has the following detachable modules: a head module 40a, two back modules 40b and 40c and two leg modules 40d, 40e.

During an operation, the position of a patient lying on the patient support surface 40 can be changed by raising or lowering the operating table column 1 and/or pivoting the patient support surface 40 about one or both of its pivot axes K-K and N-N.

To better illustrate the components of the operating table column 1, a Cartesian coordinate system X-Y-Z is shown in the figures. The Z-axis is the vertical axis, the X-axis and the Y-axis are the horizontal axes. The X-axis runs in the longitudinal direction of the foot 39 from a patient head end of the operating table 38 to the patient foot end thereof, which correspond to the head module 40a and the outer leg module 40e of the patient support surface 40, respectively. The Y axis is perpendicular to the X axis.

2 12 shows an adjustable table column 1 for an operating table according to an embodiment of the present disclosure. More precisely, the 2 the inner workings of the table column 1 1 . Accordingly, the cover 41 is not shown.

This table column 1 comprises a height-adjustable column shaft 2 and a connection unit 5 arranged at an upper end of the column shaft 2 for connecting the patient support surface 40 to the table column 1.

The column shaft 2 is divided into a lower stationary column shaft base 3 and an upper column shaft trunk 4 movable up and down relative to the column shaft base 3 . The column shaft trunk 4 includes all components located within the section delimited by the dashed line. In particular, the column shaft trunk 4 comprises two main weight-bearing components, namely a column head support 6 arranged in a lower portion of the column shaft trunk 4 and a column head 7 supported by the column head support 6 . The two Main components 6, 7 of the column stem 4 also serve as connection elements for adjacent structural components of the table column 1.

The pillar head 7 extends between the pillar head carrier 6 and the connection unit 5. The pillar head 7 is divided into a pillar head base 8 and a pillar head adjustment unit 9 which is height-adjustable in relation to the pillar head base 8.

In some embodiments, the connection unit 5 has a rectangular shape and is used for the detachable attachment of the patient support surface 40 to the table column 1.

For height adjustment, the in 2 table column 1 shown via a main lifting device 10 and an additional lifting device 11.

The main lifting device 10 is designed as a first cylindrical telescopic guide 12 . On the upper end of the first telescopic guide 12, the column head support 6 is attached. With the main lifting device 10, the column shaft stem 4 and thus also the column head carrier 6 can be moved up and down relative to the column shaft base 3.

The additional lifting device 11 is designed as a second cylindrical telescopic guide 13 . The connection unit 5 is attached to the upper end of the second telescopic guide 13 . With the additional lifting device 11, the column head adjustment unit 9 can be moved up and down relative to the column head base 8 parallel to the Z-axis ( 2 ).

The additional lifting device 11 of the column head 7 is simultaneously a tilting device 16 and a tilting device 17. With the tilting device 16, the connection unit 5 can be tilted about the Y-axis. The connection unit 5 can be tilted about the X-axis with the tilting device 17 . All adjustment movements are individually but also possible combined with each other in any way. As a result, the edging and the inclination of the patient support surface 40 can be easily adjusted.

The construction of the column head 7 enables a height adjustment of the connection unit 5 along the Z-axis (translational degree of freedom) and its pivoting about the X- and Y-axis (two rotational degrees of freedom). However, a displacement of the column head adjustment unit 9 parallel to the X and Y axes and a rotation about the Z axis must be excluded.

The device 11, 16, 17 designed for lifting, edging and tilting comprises a group of four lifting cylinders 14, 15 adjustable along the vertical Z-axis, each of which is arranged in external cylindrical guides 18 ( 2 ). A central lifting cylinder 14 is surrounded by three peripheral lifting cylinders 15 . The peripheral lifting cylinders 15 are spaced apart from one another and their upper ends are each connected to the underside of the connection unit 5 by means of a joint 19 . The two opposing lifting cylinders 15 belong to the tilting device 16. The remaining third lifting cylinder 15 belongs to the tilting device 17. The connection unit 5 is articulated to the central lifting cylinder 14 via a central joint 20. The joint 20 is, for example, a cardan ball joint or a cardanic universal joint.

In the 2 The table column 1 shown also includes a lifting drive 21 for adjusting the height of the column head 7 in relation to the column head support 6. For this purpose, each of the three extendable peripheral lifting cylinders 15 has its own, for example electronically controlled, linear motor drive 21. The three linear motor drives 21 are positioned in a housing in the column head base 8 and each have a brake with a sensor 22 . the inside 2 shown central lifting cylinder 14 does not have its own drive. In other embodiments of the table column 1, however, the central lifting cylinder 14 can have its own drive.

With such a configuration of the table column 1, the connection unit 5 or a patient support surface 40 connected to it can be inclined by different adjusting movements or their edging can be changed. In addition, if the three linear motor drives 21 are adjusted simultaneously in the same adjustment direction, the height of the connection unit 5 can be changed, i.e. it can be raised or lowered without changing its edge or inclination.

figure 3 shows a side view of the table column 1 2 , in which the connection unit 5 is inclined about the Y-axis. A cylindrical guide 23 can be seen there, which connects the column head adjustment unit 9 of the column head 7 to the column head carrier 6 . The cylindrical guide 23 has two main components. On the column head adjustment unit 9 side, this is a movable cylinder. This is the central lifting cylinder 14. On the side of the column head support 6, it is a cylindrical guide hole 37 complementary to the central lifting cylinder 14, see FIG 2 . The central lifting cylinder 14 is accommodated in the cylindrical guide hole 37 and can be moved out of it and into it again.

One task of the central lifting cylinder 14 together with the joint 20 is to block unwanted translation and rotation of the column head adjustment unit 9 along the X and Y axes and around the Z axis. The construction of the column head 7 according to the disclosure is designed in such a way that the functionality of the inclination device 16 and the tilting device 17 is not impaired.

For this purpose, the cylindrical guide 23 includes a groove 24 and a stability bar 25 together with two feather keys 26, see 3 .

4 shows in a schematic longitudinal sectional view along the line II 3 the stability bar 25 together with the two feather keys 26 interacting with the longitudinal groove 24 of the central lifting cylinder 14.

in the in 3 In the illustrated embodiment, the groove 24 is designed as a slot-like longitudinal groove which extends parallel to the Z-axis in the lateral surface of the central lifting cylinder 14 .

In particular, the stability bar 25 is a vertically oriented plate designed to increase the stability of the cylindrical guide 23 ( 3 ). You can essentially have a cuboid shape. The stability bar 25 includes two spaced-apart bores 32a for receiving adjusting screws 31 (cf. Figures 4 and 5 ). It is fastened to the column head support 6 at its two opposite ends by means of two fastening elements 34 .

A feather key is a machine element that is used to create a positive connection between two components. The feather keys 26 and the groove 24 together form a tongue and groove connection.

According to the disclosure, the keys 26 are inserted with an engagement side 28 into the keyway 24 of the cylinder 14 designed for this purpose. The feather keys 26 are fixed in bores 32b of the column head support 6, while the engagement section 28 of each key 26 received in a form-fitting manner in the groove 24 can slide in a longitudinal direction of this keyway 24 when the cylinder 14 is displaced relative to the column head support 6. Thus, each key 26 can be permanently mounted to the column head support 6 and at the same time have a sliding fit in the cylinder 14 . Such an arrangement of each feather key 26 ensures a stable extension and retraction of the cylinder 14 from the column head support 6 surrounding it.

As in Figures 4 and 5 shown, the feather keys 26 of the cylindrical guide 23 are let into bores 32b of the column head support 6 . Its function is to lock the rotation of the center lift cylinder 14 about the center Z-axis. The feather keys 26 are arranged vertically one above the other along a longitudinal axis of the longitudinal groove 24 .

Each of the two feather keys 26 comprises an elongate main body 27 with a particularly rectangular longitudinal section and an engagement element 28. The main body 27 extends along a longitudinal axis AA. The engagement element 28 is wedge-shaped and has a flat tip. It protrudes along a direction of engagement ( Figures 4-6 ).

In other embodiments, the engaging member 28 of the disclosure may be spherical, conical, triangular, rectangular, or semi-cylindrical in shape. Other shapes of the engagement elements 28 are conceivable which are sufficiently complementary to the groove 24 and ensure the sliding of the engagement elements 28 along the groove 24 . The main body 27 of the feather key 26 can, for example, be cylindrical or rectangular or have another basic shape that does not impair its functionality.

As in Figures 4-6 shown, the two engagement elements 28 of the feather keys 26 engage in the longitudinal groove 24 in order to secure the central lifting cylinder 14 against rotation about its longitudinal axis ZZ (see double file V).

The cylindrical guide 23 of the present disclosure designed in this way is provided for the controlled height adjustment of the column head 7 . It is part of the second cylindrical telescopic guide 13 of the column head 7. It enables the central lifting cylinder 14 to be moved in and out of the column head support 6.

As in Figures 4-6 shown, each key 26 is also assigned a readjustment device 29 for automatic readjustment of its seat within the longitudinal groove 24 of the central lifting cylinder 14 . Each readjustment device 29 is operated by spring force. For this purpose, it has a central, in particular T-shaped, body 36 and a set of adjacent disc springs 30 which are arranged concentrically around the body 36 and produce a preload. The setting of the spring force can be checked by means of an adjusting screw 31 of the readjustment device 29 accommodated in the bore 32a of the stability strip 25 ( Figures 4 and 5 ). The set screw 31 is arranged at the outer end of the main body 27 and directed in the engaging direction of the key 26 . By means of the spring force, the engagement elements 28 of the keys 26 in the desired position in the longitudinal groove 24 is held. Should long-term operation of the table column 1 lead to wear of the groove 24 and/or the engagement elements 28, the plate springs 30 ensure automatic readjustment so that the connection between the groove 24 and the engagement element 28 is still present and there is torsional backlash in the central lifting cylinder 14 the Z-axis cannot arise.

Since a lifting cylinder 14 stabilized in this way is connected to the underside of the connection unit 5 by means of the cardan joint 20, and the connection unit 5 is at the same time pivotably connected to the peripheral lifting cylinders 15 via the joints 19, there is also a simultaneous stabilization of the peripheral lifting cylinders 15 of the second cylindrical telescopic guide 13 against pivoting about the Z-axis.

The engagement elements 28 of the feather keys 26 are arranged offset to one another transversely to the longitudinal axis of the longitudinal groove 24 . Such an offset is realized in the example shown in that at least one of the engagement elements 28 is arranged eccentrically on its main body 27 ( figure 5 and 6 ).

It will refer to the 7 referred. This shows a horizontal section through the cylindrical guide 23. A bore 32b can be seen, the feather key 26 located therein having been left out.

In the Figures 6 and 7 1 shows the longitudinal axis AE-AE of an engaging member 28 offset parallel relative to the longitudinal axis AA of the associated main body 27 by a few tenths of a millimeter, such as at least 0.1 mm or at least 0.3 mm. Thus, the longitudinal axis AE-AE does not have a common point of intersection with the central ZZ axis of the lifting cylinder 14.

In other embodiments, the offset can be achieved in that the main bodies 27 associated with the engagement elements 28 are arranged on the column head carrier 2 with an offset relative to one another.

Due to the offset of two feather keys 26 relative to one another, their main body 27 is pressed in an opposite direction. This creates a preload in the cylindrical guide 23 transversely to the longitudinal axis of the longitudinal groove 24 and eliminates the torsional backlash in the direction of torsion about the axis Z-Z.

The present disclosure relates to cylindrical guides 23 having a plurality of keys 26, e.g. B. two, three or at least two keys 26 include.

In some embodiments, the entire bodies of the keys 26 are arranged one below the other in the direction of the vertical axis Z-Z of the lift cylinder 14 (a so-called vertical arrangement), while each of the keys 26 has an engaging element 28 which engages with a groove 24 of the lift cylinder 14. In some embodiments of the disclosure, only the main bodies 27 of the keys 26 but not the corresponding engaging elements 28 are fully vertically oriented.

For example, the longitudinal axis AE-AE of the engagement element 28 of a first key 26 may be offset parallel in a first direction relative to the longitudinal axis A-A of the main body 27 of the first key 26 . At the same time, the longitudinal axis AE-AE of the engagement element 28 of a second key 26 can either be aligned coaxially with respect to the longitudinal axis A-A of the associated second main body 27 (no offset), or the longitudinal axis AE-AE of the engagement element 28 of the second key 26 can be in a second direction, which is different from the first direction, may be staggered in parallel with respect to the longitudinal axis A-A of the second main body 27.

In other embodiments, all but one of the keys 26 may be aligned in the direction of the vertical axis Z-Z of the lift cylinder 14, while a single key 26 is laterally offset relative to a key 26 disposed above or below it.

The lateral offset of the adjacent engagement elements 28 or feather keys 26 can, for. B. in relation to side surfaces or tips of adjacent engagement elements 28 at least 0.1 mm, at least 0.3 mm, 0.1 to 3.0 mm or 0.3 to 1.0 mm. In some In embodiments, adjacent engagement members 28 may each taper toward or be biased toward either of the two longitudinal sides of the groove 24 to exert a stabilizing tension against those two sides of the groove 24 .

In some embodiments, two feather keys 26 are each let into bores 32b of the column head support 6 running perpendicularly to the vertical axis Z-Z of the lifting cylinder 14 . Both feather keys 26 can comprise asymmetrically designed engagement elements 28 which are oriented differently and, for example, point laterally in opposite directions.

In some embodiments, two feather keys 26 are each let into bores 32b of the column head support 6 running perpendicularly to the vertical axis Z-Z of the lifting cylinder 14 . The first key 26 is symmetrical and the second key 26 is asymmetrical, so that the second key 26 comprises an engagement element 28 whose longitudinal axis AE-AE is offset parallel to the longitudinal axis A-A of the main body 27 of this key 26.

In some embodiments, two keyways 26 are embedded in bores of the column head support 6, which are slightly offset relative to the perpendicular orientation of the bores 32b already described. As a result, the respective engagement elements 28 of the two feather keys 26 are also slightly offset from one another.

The keys 26 disclosed herein take a variety of forms and configurations, such as simple or complex keys 26 connected to a column head support 6 and adapted for sliding movement in a groove 24 . The keys 26 may optionally be biased toward and into the groove 24 itself by a spring or other biasing member. Such a preload ensures a self-adjusting function of the key position. The position of the keys 26 can be adjusted axially in the direction of the groove 24 and in an opposite direction. This is done either directly or by adjusting a pressure applied to the biasing member, which in turn forces the key 26 into the groove 24 and biases. Adjustment can be made using a threaded device such as a screw. The feather keys 26 can be positioned by being accommodated in bores 32a and/or stability strips 25 or using other components. The feather keys 26 can be arranged vertically adjacent to one another, with the vertical distance between the two feather keys 26 being able to be in a range of up to 5 cm and in particular in a range of up to 1 cm.

The cylindrical guide 23 is used in various applications. It can be used, for example, to stiffen telescopic elements that have a shape that deviates from the cylindrical shape. The cylindrical guide 23 is also used in lifting cylinders 14, 15, which perform a motor-assisted lifting movement or have no direct drive but have a guiding function. The cylindrical guide 23 is also used in operating tables 38 and table columns 1 with different numbers of height-adjustable lifting cylinders 14, 15.

The greatest advantage of the design of the table column 1 according to the invention is the complete elimination of the undesired torsional play in the direction of rotation about the Z-axis. Known cylindrical guide systems for table columns, which are equipped with turnstiles, are either not free of play or not self-adjusting.

Furthermore, the elimination of the rotational play increases the natural frequency of an operating table 38, part of which is the operating table column 1.

Claims (15)

1. A table column (1) for an operating table (38), comprising:

   - a column head support (6); characterized by

   - a column head (7) which is accommodated in the column head support (6) and is height-adjustable in relation thereto,

   - a lift drive (21) for adjusting the height of the column head (7) in relation to the column head support (6); and

   - a cylindrical guide (23) which connects the column head (7) to the column head support (6) and serves to vertically guide the column head (7) when adjusting its height,

   wherein the cylindrical guide (23) has a longitudinal groove (24) and two feather keys (26) which engage therein in order to secure the cylindrical guide (23) against twisting about its vertical axis,

   and wherein each feather key (26) comprises a main body (27) and an engagement element (28) which protrudes in an engagement direction and engages in the longitudinal groove (24) in the engagement direction, the engagement elements (28) of the two feather keys (26) are arranged offset to each other transversely to the longitudinal axis of the longitudinal groove (24), so that a preload is generated in the cylindrical guide (23) transversely to the longitudinal axis of the longitudinal groove (24).
2. The table column of claim 1, wherein the offset of the two engaging elements (28) is realized by virtue of at least one of the engaging elements (28) being arranged eccentrically on its main body (27).
3. The table column of claim 1, wherein the offset of the two engagement elements (28) is realized by virtue of the main bodies (27) assigned to the engagement elements (28) being arranged offset to one another on the column head support (6).
4. The table column of any one of the preceding claims, wherein the engagement elements (28) are wedge-shaped.
5. The table column of any one of the preceding claims, wherein the feather keys (26) are arranged vertically above one another along the longitudinal axis of the longitudinal groove (24).
6. The table column of any one of the preceding claims, wherein each feather key (26) is assigned a readjustment device (29) for the automatic readjustment of its seat within the longitudinal groove (24).
7. The table column of claim 6, wherein each readjustment device (29) is operated by spring force.
8. The table column of claim 7, wherein each readjustment device (29) comprises a set of disc springs (30).
9. The table column of claim 7 or 8, wherein each readjustment device (29) comprises an adjusting screw (31) for adjusting the spring force.
10. The table column of any one of the preceding claims, wherein the feather keys (26) are let into bores (32b) in the column head support (6).
11. The table column of any one of the preceding claims, wherein the cylindrical guide (23) comprises a central non-driven lifting cylinder 14 which is passively telescopically adjustable in order to follow the movement of the column head (7) when it is adjusted in height, and wherein the table column (1) further comprises at least one lifting cylinder (15) which can be driven by means of the lift drive (21).
12. The table column of any one of the preceding claims, further comprising:

    - a connection unit (5) arranged at an upper end (1a) of the table column (1), the connection unit (5) being for connecting a patient support surface (40) to the table column (1); and

    - a plurality of lifting cylinders (15);

    wherein the cylindrical guide (23) and the lifting cylinders (15) are connected to the connection unit (5) by means of articulated joints (19, 20); and wherein the cylindrical guide (23) and the lifting cylinder (15) are designed to incline the connection unit (5) about a longitudinal axis of the patient support surface (40) and to tilt an axis running transversely to the longitudinal axis of the patient support surface (40).
13. The table column of any one of the preceding claims, further comprising a main lifting device (10) which is telescopically adjustable by means of a drive, wherein the main lifting device (10) is designed to vertically adjust the column head support (6) and the cylindrical guide (23) connected thereto.
14. The table column of any one of the preceding claims, wherein the feather keys (26) are embedded in the column head support (6) and the engagement elements (28) of the feather keys (26) are preloaded in the longitudinal groove (24) by means of spring force, and wherein the longitudinal groove (24) is designed to slide over the engagement elements (28) of the feather keys (26).
15. The table column of any one of the preceding claims, wherein the main bodies (27) of the feather keys (26) are arranged in the column head support (6); wherein the longitudinal groove (24) is a groove extending vertically in the central lifting cylinder (14) of the column head (7), and wherein the longitudinal groove (24) slides perpendicularly over the engagement elements (28) of the feather keys (26) when the column head (7) is height-adjusted relative to the column head support (6).

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