EP2020217B1 - Operating table - Google Patents

Description

The invention relates to an operating table having the features of the preamble of claim 1.

Such operating tables are known to those skilled in various embodiments, for example EP-A-1 635 153 and U.S. Patent 4,869,266 , On the tabletop, a patient can be stored during an operation or examination. In the WO 2006/089399 A and the EP-A-1 634 558 A accordingly designed nursing beds are described.

A force measuring system is integrated in the operating tables. For example, this allows you to monitor the weight of the patient during an operation. Such monitoring is particularly advantageous when the patient suffers a heavy blood loss. The weight of the patient is detected by means of a force measuring system and can be displayed, for example, on a display.

The tabletop is often pivotable relative to a base plate of the support column and / or displaceable. For example, it can be provided that the table top is pivotable about a pivot axis aligned parallel or perpendicular to the table top longitudinal axis. This makes it possible to raise or lower the upper body of a patient lying on the table top or to tilt the patient around the table top longitudinal axis. It can also be provided that the table top is displaceable relative to the support column in the longitudinal or transverse direction of the table top. For pivoting or moving drive units are used, which is associated with an electronic control unit.

Object of the present invention is to develop an operating table of the type mentioned in such a way that it has an improved tilt stability.

This object is achieved in an operating table of the generic type according to the invention that the maximum swing angle or the maximum displacement relative to a zero position of the table top in response to an output signal of the force measuring system is controllable. This makes it possible, depending on the patient's weight, to limit the maximum pivoting angle or maximum displacement, so that the tilting stability of the operating table is in no way impaired when the table top is pivoted or moved. If the patient has only a comparatively low weight, a greater maximum swivel angle or a larger maximum displacement can be predefined on the basis of the output signal of the force measuring system than is the case in a patient with a relatively high weight. Rigid predetermined maximum swivel angle or maximum displacement paths can thus eliminate, rather, the maximum swivel angle as well as the maximum displacement is largely determined by the output of the force measuring system.

It is advantageous if by means of the force measuring system, the center of gravity of the table top with befindlichem patient is determinable. The mechanical load of the support column is determined by the patient's weight and its distribution and by the weight and the center of gravity of the table top with possibly existing attachable storage segments and possibly fixed to the table top equipment. It is therefore advantageous if by means of the force measuring system, the entire mechanical load of the support column can be detected.

In an advantageous embodiment, the force measuring system has a plurality of spaced-apart sensors, which are connected to a central measuring electronics. The use of several sensors makes it possible to detect the load distribution, ie. H. the distribution of the load acting on the support column. Thus, a highly uneven load distribution can be counteracted to counteract a tilting of the operating table in a timely manner.

Preferably, the table top is detachably connectable to the table column. The table top can thus be removed from the support column and mounted on demand on this. This allows the patient to be placed outside the operating room on the table top. Subsequently, the table top can be mounted with the patient mounted thereon on the support column. After the operation, the table top can be removed with the patient again from the support column and transferred to a rest room. The number of reburial of the patient can be reduced.

The force measuring system is preferably integrated in the support column. This makes it possible to use for the operating table known various tabletops, which are preferably detachably connectable to the support column. By means of the force measuring system, the load exerted by the table top and a patient on it on the support column, and preferably also the load deflection, can be determined.

The occurring during assembly of the table top on the support column and the removal of the table top of the support column lateral forces and moments The guide surfaces of the tabletop and support column, which result from a possible misalignment of the table top due to unfavorable center of gravity can be determined by the force measuring system and processed by a control unit of the operating table so that the support column is pivoted in its upper region such that no lateral Forces occur more. This facilitates the assembly and removal of the tabletop on or from the support column.

It is advantageous if the support column has a pivotable column head. For example, the column head may be adjustable in height relative to a column shaft and / or pivotable about a horizontal pivot axis. The table top can be mounted on the column head. At least one sensor of the force measuring system is preferably integrated in the column head. In particular, it can be provided that all sensors of the force measuring system and preferably also its measuring electronics are integrated in the column head. It can be provided, for example, that the column head has a top plate on which the table top can be mounted and which is pivotable relative to a support plate of the support column and preferably adjustable in height. The force measuring system is preferably arranged between the top plate and the support plate.

It is particularly advantageous if the table top is held on the support plate of the support column via a plurality of support elements, preferably via three support elements, wherein the load acting on each support element can be detected with the aid of at least one sensor of the force measuring system. The force measuring system thus has a plurality of sensors which detect the load acting on the support elements. This makes it possible, on the one hand, to determine the entire load acting on the support plate by means of the force measuring system and, on the other hand, a load distribution can be detected. The determination of such Load distribution is particularly advantageous if the table top is displaceable and / or pivotable, because by determining the load distribution can be counteracted in good time a deterioration of the tilting stability of the operating table.

Preferably, the sensors of the force measuring system are integrated in the support elements. The space required for the force measuring system can thus be kept very low. In particular, it is possible to retrofit existing operating tables with a force measuring system.

It can be provided that a single sensor of the force measuring system is integrated in each support element. However, it is particularly advantageous if each support element has at least two sensors, preferably at least four sensors, because this allows the measurement accuracy, which can be achieved by means of the force measuring system, be increased.

In a particularly preferred embodiment of the operating table according to the invention, the support elements are designed as universal joints with two hinge pins which are pivotable about parallel or perpendicular to the table top longitudinal axis pivoted axes, wherein the force acting on at least one hinge pin load by means of at least one sensor of the force measuring system can be detected. By means of universal joints, the table top can be pivoted both about a parallel to the table top longitudinal axis and about an aligned perpendicular to the table top longitudinal axis. For this purpose, preferably three universal joints are used. Preferably, the cardan joints are each held on a lifting device, so that they are adjustable in height relative to a support plate of the support column. The lifting device may for example be manually, electrically, hydraulically or pneumatically driven.

Preferably, each cardan joint is assigned a plurality of sensors of the force measuring system, in particular two or four sensors. As already explained, the measurement accuracy that can be achieved by means of the force measuring system can thereby be improved.

In a preferred embodiment, the force measuring system has sensors for detecting an electrical resistance change. The electrical resistance change can be caused by a mechanical load acting on a component of the operating table coupled to the sensors. By detecting the change in electrical resistance, the acting mechanical load can thus be determined. The sensors can provide an electrical signal that can be evaluated by an evaluation to which the sensors are connected.

The sensors can be configured for example in the form of strain gauges. These are preferably two-dimensional sensors, which are fixed to a component of the operating table, preferably glued to the component, and whose electrical resistance changes in a deformation of the component. The deformation is caused by the mechanical stress and can be detected in the form of a change in the electrical resistance of the sensor.

Preferably, two strain gauges are aligned parallel to each other. It has been shown that thereby the measurement accuracy can be increased.

It is particularly favorable if in each case four strain gauges are combined to form a Wheatstone bridge circuit. The measuring accuracy can be additionally increased, in particular temperature effects can be compensated. Such Wheatstone bridge circuits are known per se to those skilled in the art. They each have two pairs of resistors, which are connected in parallel with each other, each pair of resistors having two series-connected electrical resistors.

As an alternative or in addition to electrical sensors, in a particularly preferred embodiment of the operating table according to the invention, the force measuring system has magnetic-field-sensitive sensors for detecting a change in the magnetic field. Such sensors enable non-contact measured value acquisition. This makes it possible, for example, to determine a mechanical load by detecting the change in a magnetic field caused by the load. The determination of the mechanical load is thus based on the principle of magnetostriction, d. H. The measuring principle is based on the fact that a permanent magnet causes a change of the magnetic field caused by it during a mechanical deformation. This magnetic field change can be detected by means of the magnetic field-sensitive sensors, wherein the sensors output an electrical signal as a function of the magnetic field change caused by the mechanical load.

It is advantageous if at least one magnetic field-sensitive sensor is designed in the form of a coil. The coil can form a high-resolution magnetic scanning unit that precisely detects changes in a magnetic field.

In a preferred embodiment, the at least one magnetic field-sensitive sensor is associated with a magnetically coded ferromagnetic material which is mechanically loadable by the weight of the table top with the patient thereon. As a ferromagnetic material, for example, made of a ferromagnetic steel shaft for Use, which is subject to mechanical stress due to the weight of the patient. The load leads to a slight deformation of the shaft as a function of the size of the patient's weight. Since the shaft is magnetically coded, the magnetic field generated therefrom changes depending on the magnetic load applied to the shaft, and this magnetic field change can be detected by the at least one magnetic field sensitive sensor. To provide a magnetic field, the ferromagnetic material is magnetically encoded by being locally magnetized. The material is thus embossed with a magnetic structure that stores it permanently. The embossed magnetic structure leads to the formation of a magnetic field, which changes depending on the applied mechanical load.

It is advantageous if the ferromagnetic material is designed as a hollow shaft and the associated magnetic field-sensitive sensors are arranged within the hollow shaft. As a result, the space required for the force measuring system can be greatly reduced.

Conveniently, a signal processing element is arranged in the hollow shaft, to which the sensors positioned in the hollow shaft are connected.

In a particularly preferred embodiment, the ferromagnetic material is formed as a magnetically coded hinge pin of a universal joint. By means of the universal joint can, as already explained, the table top be held on the support column. The mechanical load exerted by the table top and the patients on it is thus absorbed by the magnetically coded hinge pins of the cardan joints, and an electrical signal is output by means of sensors arranged in the hinge pins in dependence on the applied mechanical load. Based on This signal can be used to determine the weight of the patient and the distribution of the mechanical load. In addition, based on this signal, the maximum swivel angle and the maximum displacement can be determined starting from a zero position of the table top in a structurally simple manner.

Figur 1:

eine teilweise aufgetrennte Seitenansicht eines erfindungsge- mäßen Operationstisches mit einer Tischplatte und einer Trag- säule;

Figur 2:

eine Detailansicht eines Säulenkopfes der Tragsäule aus Figur 1;

Figur 3:

eine perspektivische Darstellung eines Kardangelenkes des Säulenkopfes aus Figur 2;

Figur 4:

eine vereinfachte Darstellung des Kardangelenkes aus Figur 3 mit Sensoren eines Kraftmesssystems gemäß einer ersten Ausfüh- rungsform und

Figur 5:

eine teilweise aufgetrennte vereinfachte Seitenansicht des Kardangelenkes aus Figur 3 mit Sensoren eines Kraftmess- systems gemäß einer zweiten Ausführungsform.

The following description of preferred embodiments of the invention is used in conjunction with the drawings for further explanation. Show it:

FIG. 1:

a partially separated side view of an inventive operating table with a table top and a support column;

FIG. 2:

a detailed view of a column head of the support column FIG. 1 ;

FIG. 3:

a perspective view of a universal joint of the column head FIG. 2 ;

FIG. 4:

a simplified representation of the universal joint FIG. 3 with sensors of a force measuring system according to a first embodiment and

FIG. 5:

a partially separated simplified side view of the universal joint FIG. 3 with sensors of a force measuring system according to a second embodiment.

In FIG. 1 schematically an inventive operating table 10 is shown, which has a height-adjustable support column 12, on which a Table top 14 is releasably held. The table top 14 is designed in several parts, it comprises a support column 12 mounted on the base segment 15, on the one hand, a leg segment 16 and on the other hand, a back segment 17 are each pivotally supported about a horizontal pivot axis. At the back segment 17, a head segment 18 is held pivotably. Alternatively, the table top 14 could of course also be designed in one piece.

The support column 12 comprises a base plate 20, on which a column shaft 21 is fixed, which carries a column head 22 on the upper side. The column head 22 is in FIG. 2 shown schematically. At the column head 22, the base segment 15 of the table top 14 is releasably held.

As in particular from FIG. 2 becomes clear, the column head 22 comprises a top plate 24, on the underside of three universal joints 27, 28 and 29 are arranged. The cardan joints 27, 28 and 29 are respectively held at the free end of a spindle 31, 32 and 33, which is adjustable in height by means of a known per se and therefore not shown in the drawing drive element. The drive elements are integrated in the column shaft 21 and fixed to a support plate 35 of the column shaft 21. By raising the spindles 31, 32 and 33, the top plate 24 can be raised relative to the support plate 35. If the spindles 31, 32 and 33 are raised to the same extent, then the table top 14 is only adjusted in height while the orientation remains the same. However, if the spindles 31, 32 and 33 are raised non-uniformly, the head plate 24 and the table top 14 held on it perform a pivotal movement, wherein the table top 14 can optionally be pivoted about a parallel to the table top longitudinal axis and about an axis perpendicular to the table top axis pivot axis.

In the FIG. 2 to obtain a better overview is not shown an additional rotation of the top plate relative to the support plate 35. Such anti-rotation are known in the art and therefore require no further explanation.

The cardan joints 27, 28 and 29 are designed identically. They each have a first hinge pin 37, which is mounted pivotably about a pivot axis aligned perpendicular to the table top longitudinal axis in a U-shaped first bearing block 38. The first bearing block 38 is fixed at the free end of the respective spindle 31, 32 and 33, respectively. In addition, the universal joints 27, 28 and 29 each have a second hinge pin 40 which rests on the first hinge pin 37 and in a second bearing block 41, which is also U-shaped, about a parallel to the table top longitudinal axis aligned pivot axis is pivotally mounted. The second bracket 41 is fixed to the underside of the top plate 24.

The cardan joints 27, 28 and 29 each form a support element, via which the table top 14 is held on the support column 12. In order to detect the mechanical load acting on the cardan joints 27, 28 and 29, integrated into the cardan joints 27, 28 and 29 sensors, in combination with a in the column shaft 21, preferably between the top plate 24 and the support plate 35, arranged measuring electronics form a force measuring system with which the weight of a patient located on the table top 14 can be determined.

In the in FIG. 4 illustrated embodiment, each cardan joint 27, 28 and 29 associated with four sensors in the form of strain gauges, wherein in FIG. 4 only two strain gauges 43, 44 are visible. Two strain gauges are parallel to each other on the first hinge pin 37 of each universal joint 27, 28 and 29 fixed by means of an adhesive bond, wherein the second hinge pin 40 is positioned between the two strain gauge pairs. The first hinge pin 37 thus carries a total of four strain gauges, which are connected together in a conventional manner in the form of a Wheatstone bridge bridge. By means of the strain gauges 43, 44, the mechanical load acting on the first hinge pin 37 can be determined. Since each universal joint 27, 28 and 29 corresponding strain gauges are assigned, thus, on the one hand, the total load, which acts on the cardan shaft 21 via the cardan joints 27, 28 and 29, can be determined, and beyond the load distribution can be detected. The acting load results from the weight of the table top 14 and the head plate 24 and from the weight of the patient located on the table top 14. Thus, the patient weight can be determined from the total load.

The strain gauges 43, 44, which are each associated with a first hinge pin 37, are connected via connecting wires, which are not shown in the drawing to achieve a better overview, with a arranged in the interior of the form of a hollow shaft first hinge pin 37 signal processing member. From this signal processing element leads a connection cable 46 to the already mentioned central measuring electronics, which is arranged for example in the column shaft 21. Based on the signals from the signal processing members of the cardan joints 27, 28 and 29, an output signal is provided by the meter electronics in response to the mechanical load applied to the cardan joints 27, 28 and 29. In response to this output signal from a central control unit of the operating table 10, the maximum pivot angle by which the table top 14 can be pivoted, also determined as the maximum displacement to which the table top 14 relative to the support column 12 in the tabletop longitudinal direction or can be moved transversely to the tabletop longitudinal direction. Maximum pivot angle and maximum displacement of the table top 14 are thus determined depending on the weight of the patient. The greater the patient weight, the lower the maximum pivot angle and the maximum displacement are chosen to ensure optimal stability of the operating table 10 in each case.

In FIG. 5 a second embodiment of a force measuring system is shown, which can be used at the operating table 10. Also in this embodiment, the first hinge pin 37 of the universal joints 27, 28 and 29 are each formed as a hollow shaft, which carries in its interior a signal processing member 49 from which a connection cable 50 leads to the outside. About the connecting cable 50, the signal processing member 49 is connected to the central measuring electronics of the operating table 10, which is arranged for example in the column shaft 21. At the in FIG. 5 1, the first hinge pin 37 of the cardan joints 27, 28 and 29 is made of a ferromagnetic material, preferably an industrial steel is used, which contains between 1.5% and 8% nickel. The first hinge pin 37 has on both sides of the second hinge pin 40 each have a magnetic coding, ie on both sides of the second hinge pin 40, the ferromagnetic first hinge pin 37 was magnetically encoded by him a magnetic structure was impressed by applying a very strong external magnetic field. This magnetic structure keeps the first hinge pin 37 permanently. In the area of the magnetic coding, in each case four magnetic-field-sensitive sensors are arranged in the form of coils within the first hinge pin 37 on both sides of the second hinge pin 40, which are each connected to the signal processing element 49. In FIG. 5 are to achieve a better overview on both sides of the second hinge pin 40 each have three coils 53, 54 and 55th shown. Acts on the magnetically coded first hinge pin 37, a mechanical load, this leads to a change in the detectable by the coils 53, 54 and 55 magnetic field. The magnetic field change is transmitted in the form of an electrical signal via the connecting cable 50 to the central measuring electronics. This determines from the loads acting on the individual universal joints 27, 28 and 29 the weight of the patient located on the table top 14 and the load distribution.

At the in FIG. 5 illustrated embodiment, the mechanical load is detected without contact with very high accuracy. Through the use of hollow shafts for the first hinge pin 37, the force measuring system requires no additional space and is therefore also suitable for retrofitting existing operating tables. As with the reference to FIG. 4 shown force measuring system can also by means of in FIG. 5 not only the patient's weight can be determined, but in addition, depending on the patient's weight, a maximum pivoting angle and a maximum displacement, starting from the in FIG. 1 shown zero position of the table top 14, to be determined.

Claims (21)

1. Operating table having a support column (12), a table panel (14) which is mounted on the support column (12) and is pivotable and/or displaceable, and a force measurement system for determining the weight of the table panel (14) and of a patient on the table panel (14), characterized in that the maximum pivot angle and/or the maximum displacement relative to a neutral position of the table panel (14) can be controlled in dependence on an output signal of the force measurement system.
2. Operating table according to Claim 1, characterized in that the location of the center of gravity of the table panel with the patient thereon can be determined by means of the force measurement system.
3. Operating table according to Claim 1 or 2, characterized in that the force measurement system has a plurality of sensors (43, 44; 53, 54, 55) arranged at a spacing from one another, which are connected to central measuring electronics.
4. Operating table according to any of the preceding claims, characterized in that the table panel (14) is releasably connectable to the support column (12).
5. Operating table according to any of the preceding claims, characterized in that the force measurement system is incorporated into the support column (12).
6. Operating table according to any of the preceding claims, characterized in that the support column (12) has a pivotable column head (22), into which at least one sensor (43, 44; 53, 54, 55) of the force measurement system is incorporated.
7. Operating table according to any of the preceding claims, characterized in that the table panel (14) is mounted by way of a plurality of supporting elements (27, 28, 29) on a support plate (35) of the support column (12), the load acting on each supporting element (27, 28, 29) being detectable by means of at least one sensor (43, 44; 53, 54, 55) of the force measurement system.
8. Operating table according to Claim 7, characterized in that the sensors (43, 44; 53, 54, 55) are incorporated into the supporting elements (27, 28, 29).
9. Operating table according to Claim 7 or 8, characterized in that the supporting elements are each formed as a cardan joint (27, 28, 29) having two pivot bolts (37, 40), which are pivotably mounted about pivot axes aligned respectively parallel to or at right angles to the longitudinal axis of the table panel, the load acting on at least one of the pivot bolts (37) being ascertainable by means of at least one sensor (43, 44; 53, 54, 55).
10. Operating table according to Claim 9, characterized in that a plurality of sensors (43, 44; 53, 54, 55) is assigned to each cardan joint (27, 28, 29).
11. Operating table according to Claim 9 or 10, characterized in that at least four sensors (43, 44; 53, 54, 55) are assigned to each cardan joint (27, 28, 29).
12. Operating table according to any of the preceding claims, characterized in that the force measurement system has sensors (43, 44) for detecting a change in electrical resistance.
13. Operating table according to Claim 12, characterized in that at least one sensor is provided in the form of a strain gauge (43, 44).
14. Operating table according to Claim 13, characterized in that each two strain gauges are aligned parallel to one another.
15. Operating table according to Claim 13 or 14, characterized in that every four strain gauges are assembled into a Wheatstone bridge circuit.
16. Operating table according to any of the preceding claims, characterized in that the force measurement system has sensors (53, 54, 55) which are sensitive to magnetic fields, for detecting a change in a magnetic field.
17. Operating table according to Claim 16, characterized in that at least one sensor which is sensitive to magnetic fields is provided in the form of a coil (53, 54, 55).
18. Operating table according to Claim 16 or 17, characterized in that a magnetically coded ferromagnetic material is associated with the at least one sensor (53, 54, 55) which is sensitive to magnetic fields, and the material is mechanically loadable by the weight of the table panel (14) with the patient thereon.
19. Operating table according to Claim 18, characterized in that the ferromagnetic material is formed as a hollow shaft (37) and the associated sensors (53, 54, 55) which are sensitive to magnetic fields are located within the hollow shaft (37).
20. Operating table according to Claim 19, characterized in that a signal processing element (49) is located in the hollow shaft (37), and the sensors (53, 54, 55) which are sensitive to magnetic fields and are located in the hollow shaft (37) are connected to the signal processing element.
21. Operating table according to Claim 18, 19 or 20, characterized in that the ferromagnetic material forms a magnetically coded pivot bolt (37) of a cardan joint (27; 28; 29).

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