DE9116002U1 - Headrest for an operating table, operating chair or similar. - Google Patents

Description

Headrest for an operating table, operating chair or dal.

The subject matter of the invention is a headrest for an operating table, operating chair or the like according to the preamble of claim 1. Such headrests are used in particular in medical or dental treatment in the head area.

In conventional headrests, a headrest can have a padded support table and the associated support can have a parallelogram gear that can be locked in various positions with a motor drive. This allows the head to be moved in

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Attorney: admitted to the Hamburg courts

Deutsche Bank AG Hamburg N.. 05/28497 ,BLZ 2OT 7CO OC) ■ Postgiro Hamburg 28 42-206
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the vertical, which is associated with a nodding movement of the head relative to the body resting on the operating table.

Furthermore, a headrest is known from DE-OS 34 40 589, the headrest of which is height-adjustable and tiltable for a pitching movement using several swivel joints aligned horizontally in the transverse direction of the support. The support also has a joint aligned perpendicularly to it for a yawing movement of the head and is adjustable in the longitudinal direction relative to a fastening section for the operating table.

DE-GM 75 10 319 discloses a headrest whose headrest is pivotably mounted on the support by means of a ball joint.

With conventional headrests, adjusting a joint requires the head to be completely moved from its original position. This is particularly disadvantageous for treatments in which the surgical site on the head is moved from its original position. This usually requires the doctor to adopt a new position and, if necessary, to realign aids such as a microscope suspended from the ceiling.

If during treatment, e.g. to improve accessibility or change the viewing angle, the operation site needs to be realigned, this is very time-consuming due to the changes in position of the patient, the doctor and the equipment. In addition, the headrests are often only manually adjustable, which for hygiene reasons should not be done by the treating doctor but by an additional person.

Based on this, the invention is based on the object of improving a headrest of the type mentioned at the beginning so that adjustment is less complex.

The solution to this problem is specified in claim 1. Advantageous embodiments can be found in the subclaims.

According to the invention, a virtual pivot point of the position is placed approximately in an operation site of a head to be placed above the headrest. This point is to be determined based on known head dimensions and can, in individual cases, be made to roughly coincide with the part of the head to be treated, e.g. by padding the headrest. If the

If the surgical site is in the virtual pivot point, it can be pivoted by pivoting the headrest relative to the wearer. This only changes its orientation to an observer, a microscope or a treatment instrument, so that the treatment can be continued without changing the position of the observer or instrument. This significantly reduces the treatment effort.

Preferably, the bearing has a rolling axis that runs through the virtual pivot point in the longitudinal direction of the headrest, around which the head can pivot or roll. This avoids a complex compensating movement by the surgeon and his instruments, which can also be directed across the operating table.

To create a swivel or roll axis, the bearing can have rollers with a circular cylindrical pipe section supported on one or both sides. The center axis of curvature of the pipe section defines the swivel or roll axis around which a head resting on it is swiveled as the pipe section passes through the rollers in certain areas. This creates a particularly robust and precise bearing.

A drive for the head support can have a circumferential toothing, i.e. a toothing of the pipe section running in the circumferential direction and a drive gear that meshes with it. This simple drive part also has self-locking properties, which help to fix the head in a certain swivel position. The circumferential toothing can be simply implemented using a toothed belt attached to the pipe section at two end points. To ensure a safe transfer of the drive force, the toothed belt can point with a tooth profile towards the pipe section and be wrapped around the drive gear between two deflection rollers over a large wrap angle. A structural unit is advantageously formed by mounting the rollers, deflection rollers and/or the drive gear in the side walls of a bearing block.

A virtual pivot point in an operation site above the headrest can be implemented kinematically in various ways. For example, the bearing of a spherical shell with a spherical cap supported in it can have a movement of the spherical shell relative to the spherical cap allowing the head to pivot in any spatial direction around the virtual pivot point. To position the spherical shell in a specific pivot position, at least one length-fixable

-S-

Telescopic device hingedly attached to the spherical cap and a point fixed with respect to the spherical shell.

Preferably, the pipe section or spherical cap is connected to the headrest and rollers or spherical shell is connected to the support. Then the pipe section or spherical cap does not need to protrude laterally beyond the headrest in any swivel position.

Furthermore, the bearing can have a multi-joint with an instantaneous center of gravity located approximately at the virtual pivot point. The head support is then connected to the gear element, which can pivot around the instantaneous center of gravity.

The headrest preferably has a support table connected to the support. This can serve as a basis for variable padding, which is adapted to the shape of the head and the surgical site.

Preferably, the support table carries a yaw table that can be pivoted about a yaw axis that is aligned vertically to the support table and runs approximately through the virtual pivot point. This allows a yaw movement of the head about the virtual pivot point, as far as the atlas joint allows. A drive for the head support has

preferably a circular toothing, i.e. a toothing of the yaw table arranged on a circle around the yaw axis, as well as a drive pinion that meshes with it and is mounted on the support table. This simple drive part also provides advantageous self-locking in a certain swivel position.

The position of the virtual pivot point relative to the headrest is determined by the kinematics of the support. In order to bring an operation site into the pivot point, the head must be positioned by padding the headrest, longitudinal displacement and transverse displacement of the body. So that a headrest with an interfering width does not have to be provided for the latter movement, it preferably has a cover plate that can be fixed in a variable position in the transverse direction. If the operation site is on a central plane through the head, the cover plate is fixed to the headrest in approximately the middle position. If an operation site is located to the side of the central plane, the cover plate is fixed in a shifted position according to the distance of the operation site from the central plane. As a result, the head can always have approximately the same position relative to the cover plate, so that this and the headrest can be designed to be relatively narrow. In this case, it is only necessary to ensure that there is a variability factor.

The cover plate fixation area allows an arrangement of all conceivable operation sites in the virtual pivot point. The cover plate for this is preferably a perforated plate with fastening holes distributed transversely for screw fastening to the headrest.

If the operation site is brought into the virtual pivot point by padding, the head performs a nodding movement as a result of the headrest being fixed to the operating table. This is only desirable or permissible to a limited extent. To adjust the position of the head to the position of the body on the operating table, a preferred design provides that the carrier has a parallelogram gear between the bearing and a fastening device for fixing to the operating table with a parallel displacement axis directed approximately in the direction of a vertical axis perpendicular to the head support surface and a locking device for various displacement positions. The parallelogram gear allows the head support to be adjusted vertically relative to the operating table, which is practically not accompanied by a relative movement in the longitudinal direction of the body. The two bearing-side articulations of the joint rods of the parallelogram gear can be spaced further apart than the fastening device-side articulations. Then the

Movement of the head upwards is combined with a nodding movement in the direction of the chest and the movement of the head downwards is combined with a nodding movement in the direction of the back, whereby the head is guided in an anatomically favorable manner.

A drive for the headrest for its vertical movement can have a linear drive that is connected to a bearing-side linkage of one joint rod and to a fastening device-side linkage of the other joint rod. The linear drive thus runs diagonally across the joint rods, so that its adjustment causes a change in the diagonal and thus the alignment of the parallelogram gear. In a practical embodiment, the linear drive has a threaded spindle that is turned into a spindle nut of one linkage on the one hand and is mounted in a pivot bearing of the other linkage on the other hand.

If an operation site is arranged at a distance from the center plane of the head in the virtual pivot point, a transverse displacement of the body on the operating table is generally required. However, providing an operating table that is too wide can be avoided if the carrier has a transversely directed

.../10

the headrest has a transverse guide rail and a guide block that can be moved to it and locked in different positions. The body can then always lie approximately centrally on the operating table, whereby an offset of the operation site to the central plane is achieved by moving the headrest sideways using the guide block and transverse guide rail.

Another embodiment with the same purpose uses the lateral displacement of the bearing block relative to the housing part on the bearing side of the parallelogram. The displacement is implemented with a simple linear guide, e.g. a dovetail guide.

Preferably, at least one drive for the headrest has a drive motor, which eliminates the need for conventional manual drive devices. The positioning of the headrest can then be carried out directly by the treating physician. For this purpose, each drive motor preferably has a switch for hand or foot operation. In the case of manual operation, the switch can be designed as a control lever and in particular attached to the bearing block, which makes it easy to reach. The control lever can operate the switches for up to three motors. Each switch can have two or more switching levels for

.../11

- have 11 different speeds.

Further details and advantages of the subject matter of the invention emerge from the following description of the associated drawings, which show preferred embodiments. In the drawings:

Fig. 1 a headrest pivotable about a rolling axis on an operating table in a perspective side view;

Fig. 2 Headrest of the same type in a slightly enlarged
front view;

Fig. 3 and 4 the same headrest in two pivoting positions around the roll axis in front view;

Fig. 5 the same headrest in raised position in longitudinal section;

Fig. 6 the same headrest in lowered position in longitudinal section;

Fig. 7 a headrest with ball-castellated bearing in
schematic cross-section;

.../12

Fig. 8 and 9 the same headrest in two pivoting positions around the surgical site;

Fig. 10 a four-bar linkage as a bearing for an additional headrest in a schematic front view.

According to Fig. 1, a headrest 1 is attached to an operating table 2, which has lateral fastening rails 3 for this purpose. Tubular plug ends 4 of the headrest 1 are attached to the head ends of the fastening rails 3 and secured there by means of clamping screws 5.

The plug ends 4 on both sides are connected to one another by a transverse guide rail 6, which carries a guide block 7 that can be moved in the transverse direction A. The guide block 7 overlaps the transverse guide rail 6 with a hook-shaped end and can be fixed in any desired position by means of a clamping screw 8.

The guide block 7 supports a parallelogram gear 9 in parallel side walls, which has two parallel sets of joint rods 10, 11. On the other hand, the joint rods 10, 11 are supported in parallel side walls of a support block 12. Between the two sets of joint rods 10, 11 there is a linear drive 13, which is mounted on a lower

.../13

Bearing of the guide block 7 and an upper bearing of the support block 12 and thus extends diagonally through the parallelogram gear 9.

By means of the linear drive 13, the support block 12 can be moved approximately parallel to the vertical axis C. Due to the different distances between the joint rod links in the guide block 7 and in the support block 12, it performs a pitching movement in the direction of arrow B around the transverse axis A.

The support block 12 carries a bearing block 14, which forms a bearing with a circular cylindrical pipe section 15. The pipe section 15 can be pivoted by means of a rolling drive motor 16 in the bearing block 14 in the direction of arrow E about a rolling axis, which falls in the central axis of the pipe section 15.

A support table 17 is fixed to the top of the pipe section 15, which supports a yaw table 18. The yaw table 18 can be pivoted in the direction of arrow D about a yaw axis extending perpendicularly to the support table 17 in the direction C. For this purpose, a yaw drive motor 19 is mounted on the support table 17, which has a drive pinion that meshes with a circular toothing of the yaw table 18.

.../14

The yaw table 18 carries a perforated plate 20 which has a row of fastening holes oriented in the transverse direction A. A fastening screw 21 is inserted into a fastening hole and screwed into a threaded hole in the yaw table 18. By fixing the fastening screw 21 in another fastening hole, the perforated plate 20 can be arranged in a different position in the transverse direction A.

The perforated plate 20 carries a padding 22 made of a foam material in horseshoe shape, which forms a support for a head.

If a person is lying on the central axis of the operating table 2, any operation site on the head can be brought into the center of the roll axis. To do this, the bearing block 7 must be moved in the transverse direction A so that the roll axis is approximately aligned with the operation site and the perforated plate 20 must be fixed to the yaw plate 18 so that the head can be placed on the headrest 22. In the direction of the vertical axis C, the roll axis can be pushed into the operation site by changing or layering the padding 22. In this case, by adjusting the parallelogram gear 9, it can be ensured that the head is placed in a desired pitch position for

.../15

body. A slight pitching movement in the direction of arrow B is achieved in the manner described above by the asymmetrical mounting of the two sides of the parallelogram gear 9.

In the other figures, parts corresponding to Fig. 1 are designated with identical reference numbers. Figs. 2 to 4 show further details of a bearing of a similar headrest 1, which supports a schematically indicated head 23. For this purpose, the padding 22 is arranged directly on the support table 17.

The pipe section 15 on the underside of the support table 17 can be pivoted relative to the bearing block 14.

As can be seen from the detailed Fig. 3, the bearing block 14 has an upper roller 24 and two lower rollers 25, which support the pipe section 15 at the top and bottom. Furthermore, a toothed belt 26 is provided on the underside of the pipe section 15, which is guided via guide rollers 27 onto a drive gear 28 of the roller drive motor 16.

The bearing allows the head 23 to be pivoted in both directions by approximately 20° around a rolling axis through the

.../16

virtual pivot point D, which coincides with the central axis of the tube section 15. Thus, an operating point of the head 23 is only pivoted on the roll axis.

Fig. 5 and 6 show further details of the parallelogram gear of a similar device. Instead of a guide block 7, a fixing block 7' is provided here, which is connected via a cross member 6' instead of a cross guide rail with plug ends 4 for fastening to the operating table 2.

The joint rods 10, 11 are mounted on the one hand between the side walls of the fastening block 7' and on the other hand between the side walls of the support block 12, with their bearing points on the side of the fastening block 7' being closer to each other than on the side of the support block 12. The bearing between the support table 17 and the support block 12 is designed as in Fig. 2 to 4, but is not shown in detail.

As the comparison of Fig. 5 and 6 shows, the different joint spacing on both sides of the joint rods 10, 11 means that a head 23 resting on the padding 22 is directed towards the chest when raised and towards the head when lowered.

.../17

- 17 makes a slight nodding movement towards the back.

Furthermore, details of the linear drive 13 for adjusting the parallelogram gear are shown. It has a threaded spindle 29 that is rotatably mounted in a pivot bearing 30 that is pivotably mounted on the lower joint of the fastening block 7'. For this purpose, the pivot bearing 30 has two roller bearings 31 in a sleeve-shaped body and the threaded spindle 29 is supported in the axial direction on the roller bearings 31 via screwed-on fastening plates 32.

The pivot bearing carries a drive motor 33 which is connected to the threaded spindle 29 via a gear 34.

On the other hand, the threaded spindle 29 is guided by a spindle nut 35 which is fixed in a bearing sleeve 36, which is mounted on the upper joint of the support block 12. At this end, the threaded spindle is connected to a guide sleeve 37 which slides in the sleeve 36 and, in addition to providing lateral guidance, also provides an end stop.

When the drive motor 33 is actuated, the distance between the sleeve 36 and the pivot bearing 30 changes, so that the parallelogram gear is adjusted and the head 23 is raised

.../18

- 18 or lowered.

According to Fig. 7 to 9, another headrest 1' is connected to an operating table via a strut 38. On the strut 38 there is a bearing shell 39 with a bearing surface in the form of a spherical shell 40. On the bearing surface there is a spherical cap 41 which has a support table 17 with a padded perforated plate 20 for a head 23 at the top. On the underside of the spherical cap 41 there are telescopic locking devices 42 for fixing the spherical cap in any swivel position on the spherical shell 40.

Starting from a central position according to Fig. 7, a head 23 can thus be pivoted by a pivot angle of 20° in any spatial direction around a virtual pivot point D, which falls into an eye in the position of the head 23 shown in more detail (Fig. 7). The further head position (in Fig. 7) shows that by moving the perforated plate 20 on the support table 17, other operating sites or positions outside the head can be pushed into the virtual pivot point.

Fig. 10 shows a four-bar linkage which can replace the above-discussed bearing arrangement consisting of pipe section 15 and rollers 25.

.../19

For this purpose, two joint rods 43, 44 are hinged to a body 45, which can be, for example, the bearing block 12 according to Fig. 1. The other ends of the joint rods 43, 44 are connected to one another in an articulated manner via a further joint rod 46. This gear arrangement means that the joint rod 46 can be pivoted approximately around an instantaneous pole M. Thus, by connecting the joint rod 46 to a support table, a rolling movement of a head around a rolling axis approximately through the instantaneous pole M can be realized.

To adjust the gear, an adjusting spindle 46 with a spindle wheel 47 is provided, which is supported axially on the body 45 and can rotate, the thread of which carries a spindle nut 48. The spindle nut 48 articulates a guide rod 49 which is rigidly connected to the joint rod 46, so that a rotation of the threaded spindle 46 causes a pivoting of the joint rod 46.

.../20

Claims (25)

- 20 claims 1. Headrest for an operating table, operating chair or the like, with a headrest, a support for the headrest that can be fixed to the operating table and a pivotable mounting of the headrest on the support, characterized in that the mounting (14, 15) has a virtual pivot point (D) approximately in an operating location of a head to be placed above the headrest (22). 2. Headrest according to claim 1, characterized in
that the bearing (14, 15) has a rolling axis running through the virtual pivot point (D) in the longitudinal direction of the head support (22). 3. Headrest according to claim 2, characterized in
that the bearing has rollers (24, 25) with a circular cylindrical tube section (15) supported on one or both sides. 4. Headrest according to claim 3, characterized in
that a drive for the pipe section (15) has a peripheral toothing (26) of the pipe section and a drive gear (28) meshing therewith. .../21 5. Headrest according to claim 4, characterized in that the circumferential toothing is formed on a toothed belt (26) fastened to two end points on the tube section (15). 6. Headrest according to claim 5, characterized in that the toothed belt (26) has a tooth profile facing the pipe section (15) and is wound around the drive gear (28) between two deflection rollers (27, 28). 7. Headrest according to one of claims 3 to 6, characterized in that the rollers (24, 25), deflection rollers (27, 28) and/or the drive gear (28) are mounted in side walls of a bearing block (14). 8. Headrest according to claim 1, characterized in that the bearing has a spherical shell (40) with a spherical cap (41) supported thereon. 9. Headrest according to claim 8, characterized in that at least one length-fixable telescopic device (42) is articulated to the spherical cap (41) and to a point fixed with respect to the spherical shell (40). 10. Headrest according to one of claims 3 to 9, characterized .../22 characterized in that the pipe section (15) or spherical cap (41) is connected to the head support and rollers (24, 25) or spherical shell (40) are connected to the carrier. 11. Headrest according to claim 1 or 2, characterized in that the bearing has a multi-joint (43, 44, 46) with an instantaneous pole (M) arranged approximately in the virtual pivot point. 12. Headrest according to one of claims 1 to 11, characterized in that the headrest has a support table (17) connected to the bearing. 13. Headrest according to claim 12, characterized in that the support table (17) carries a yaw table (18) which is pivotable about a yaw axis aligned vertically to the support table and running through the virtual pivot point. 14. Headrest according to claim 13, characterized in that a drive for the headrest has a circular toothing of the yaw table (17) concentric to the yaw axis and a drive pinion meshing therewith and mounted on the support table (17). .../23 15. Headrest according to one of claims 1 to 14, characterized in that the headrest carries a cover plate (20) which can be fixed in a variable position in the transverse direction. 16. Headrest according to claim 15, characterized in that the cover plate is a perforated plate (20) which has fastening holes distributed in the transverse direction for a screw fastening to the headrest. 17. Headrest according to one of claims 1 to 16, characterized in that a padding (22) of the headrest forms a support for a head. 18. Headrest according to one of claims 1 to 17, characterized in that the carrier has a parallelogram gear (7, 10, 11, 12) with a parallel displacement axis directed in the direction of the vertical axis and a locking device for different displacement positions between the bearing (14, 15) and a fastening device (4, 5) for fixing to the operating table (2). 19. Headrest according to claim 18, characterized in that the two bearing-side articulations of the .../24 steering rods (10, 11) of the parallelogram gear are spaced further apart than the two linkages on the fastening device side. 20. Headrest according to claim 18 or 19, characterized in that a drive for the headrest has a linear drive (13) which is articulated to a bearing-side articulation of one articulated rod (11) and to a fastening device-side articulation of the other articulated rod (10). 21. Headrest according to claim 20, characterized in that the linear drive (13) has a threaded spindle (29) which is mounted on the one hand in a spindle nut (35) of one linkage and on the other hand in a rotary bearing (30) of the other linkage. 22. Headrest according to one of claims 1 to 21, characterized in that the support between the bearing (14, 15) and the fastening device (4, 5) for fixing to the operating table has a transverse guide rail (6) running in the transverse direction of the headrest and a guide block (7) which can be displaced thereon and locked in different positions. .../25 23. Headrest according to one of claims 1 to 22, characterized in that the bearing block (14) can be displaced relative to the support block (12) in the direction of the axis on a linear guide. 24. Headrest according to one of claims 1 to 23, characterized in that at least one drive for the headrest has a drive motor (16, 19, 33). 25. Headrest according to claim 24, characterized in that hand- or foot-operated switches with one or more switching stages and, depending on the design, with a common control lever are provided for each drive motor (16, 19, 33).