WO2023006649A1

WO2023006649A1 - Bearing assembly of a control plate on a shaft, and surgical instrument

Info

Publication number: WO2023006649A1
Application number: PCT/EP2022/070764
Authority: WO
Inventors: Sven Axel Grüner; Dominik Längle; Janosz SCHNEIDER; Jochen Stefan
Original assignee: Karl Storz Se & Co. Kg
Priority date: 2021-07-28
Filing date: 2022-07-25
Publication date: 2023-02-02
Also published as: DE102021119521B4; DE102021119521A1

Abstract

The present invention relates to a bearing assembly (40) of a control plate (14) on a shaft (21), and to a surgical instrument (1) having a main shaft (21) extending coaxially with a shaft (2), which main shaft forms such a bearing assembly together with a control plate (14). The bearing assembly (40) is provided by: - at least one guide groove (22), which extends longitudinally in the shaft (21); and - at least one pin (42), which is situated on the control plate (14) and points radially inwards. The pin (42) engages in the guide groove (22) such that a rotational angle of the shaft (21) can be transmitted to the control plate (14).

Description

Bearing arrangement of a swash plate on a shaft and surgical instrument

The invention relates to a bearing arrangement for a swash plate on a shaft and to a surgical instrument which has such a bearing arrangement.

Surgical instruments are known from the prior art, which can be guided manually or by a robot, and which have tools whose tool tip can be pivoted by means of a plurality of interlocking pivoting members. These pivot links are connected to a variety of steering wires or cables to provide fine control of the tool tip. A more even force distribution in all bending directions can be achieved with many thin steering wires compared to a few thicker steering wires.

It is known from US Pat. No. 5,454,827 to couple such steering wires to a spatially adjustable disc arranged in an actuation unit on the proximal side, which is connected via a rod to a manually operable control lever, so that movement of the spatially adjustable swash plate causes a corresponding relative movement of the distalsei term pivoting members and thus pivoting of the tool tip.

The design of the drive for the steering wires with the spatially adjustable swash plate on which the steering wires are mounted has the advantage that this enables a spatially com pact design and only one component has to be moved in order to be able to address all steering wires.

US Pat. No. 10,105,128 B2 discloses a surgical instrument with a mechanism to control the rotation of a swash plate in two degrees of freedom via link rods with drives on the proximal side. Alternatively, a gimbal mounting is proposed for moving the swash plate, which has gimbal mounts arranged on a base plate, which provide an axis of rotation for a gimbal ring, which in turn provides an axis of rotation for the swash plate, which is therefore not rotatable in the instrument.

The alternative use of a universal joint disk with two pairs of pins crossed at right angles for cardanic mounting of a swash plate on an instrument shaft, in which one pair of pins is connected to the shaft and one pair of pins to the swash plate, is associated with higher procurement, storage and and assembly costs. In addition, the gimbal mounting with the universal joint disc, due to the principle involved, requires a very large installation space at high angle offsets, which prevents miniaturization of the instrument's proximal-side drive.

Other coupling variants that can potentially be used as alternatives between a shaft and a swash plate have different disadvantages. Although a curved tooth coupling can be built very compactly, it only allows a very small angular misalignment. Due to the raceways, constant velocity joints require relatively complex individual parts and are more complex to assemble due to the balls. Cohesive couplings with a certain degree of freedom from play often have a spring component and therefore an indirect transmission of the angle of rotation due to the elasticity. Especially with Zforce changes in direction, full unloading occurs first, followed by tension in the other direction before movement is passed on. The angular function of the transmission is strongly dependent on the torque. Based on this prior art, it is the object of the present invention to provide a mounting arrangement for a swash plate on a shaft, which can be a main shaft of a surgical instrument, which is simplified in terms of assembly effort, the swash plate being intended to create a starting situation for the smallest possible construction space requirement.

This object is achieved by a bearing arrangement having the features of claim 1.

The further object of providing a surgical instrument that has a structurally simple and space-saving storage arrangement for the spatially adjustable swash plate, even with large angular offsets, is achieved by the surgical instrument with the features of independent claim 8 .

Further developments and preferred embodiments of the storage arrangement and the surgical instrument are set out in the dependent claims.

A first embodiment of the bearing arrangement according to the invention for a swash plate on a shaft provides that the shaft has at least one guide groove in front of its outer surface, which extends along the shaft, the swash plate being designed in the shape of a circular ring with an outer side and an inner side , has at least one pin arranged pointing radially inwards on the swash plate. In the bearing arrangement, at least one of the two pins mounted firmly on or in the swash plate engages in the at least one guide groove, so that an angle of rotation of the shaft can be transferred to the swash plate.

This advantageously results in a torsionally rigid connection between the shaft and the swash plate, which allows a rotational angle to be transmitted even with a large angular misalignment (± 40° and more) and axial misalignment, while still being very compact and easy to manufacture and assemble.

According to a preferred embodiment of the bearing arrangement according to the invention, the shaft has two guide grooves present in its outer surface, which grooves extend diametrically and longitudinally along the shaft, the swash plate having two pins arranged diametrically and pointing radially inwards on the swash plate, which in the bearing arrangement Order intervene in a respective guide groove. The symmetrical structure ensures a more even power transmission and a more secure guidance of the bearing arrangement.

The bearing arrangement according to the invention is therefore particularly suitable for installation in a surgical instrument, the shaft being a main shaft of the surgical instrument which has a shaft which runs coaxially to a longitudinal axis of the main shaft and which can preferably be a hollow shaft. At the proximal end of the shaft there is an actuating unit and at the distal end of the shaft there is a tool tip with a tool that can be actuated via an actuating element that is mounted in the shaft in an axially displaceable manner, which also extends through a longitudinal-axial through-bore of the main shaft and comes proximally with it the actuating unit is in operative connection. The bearing arrangement according to the invention is designed for the spatial alignment of the swash plate in relation to the main shaft in cooperation with a drive on the proximal side, so that a movement of the drive on the proximal side causes the tool tip to pivot. Furthermore, the bearing arrangement according to the invention provides the possibility of compensating for an axial offset, because this avoids an overdefinition of the axial position in the drive on the proximal side. The connection to the proximal side drive can then determine the unambiguous axial position.

A maximum permissible tilting of the swash plate can be predetermined by the chosen length and depth of each guide groove. Ie., The length and depth of the guide grooves are determined by the desired maximum tilting of the swash plate, with a larger axial offset can be made possible by the guide grooves can also be correspondingly extended in the respective direction. Furthermore, the achievable tilt angle can depend on a ratio between the outer diameter of the main shaft and the inner diameter of the swash plate.

To mount the swash plate on the shaft to provide the storage arrangement according to the invention by engaging the pins in the guide grooves, which are limited in terms of their length, the swash plate can be pushed onto the shaft until it is in the area of the guide grooves, whereupon the pins are mounted on the swash plate. so that they can engage in the guide grooves. The same applies to a location arrangement arrangement with a guide groove in the shaft and a pin in the swash plate. To insert the pins, the swash plate can have diametrically radial passage have bohmngen, so that the pins can be inserted from the outside of the swash plate through the through hole until they emerge on the inside of the swash plate and protrude radially inward. The same applies here for a swash plate with only one pin.

In an alternative assembly process, the pins can be pre-assembled in the through-holes of the swash plate before they are arranged on the shaft, or alternatively, designed swash plates can be used in which the through-holes are not introduced into the finished swash plate from the outside. Alternatively designed swashplates can be produced, for example, using an additive manufacturing process or can be assembled from two partial disks that are divided in the radial or axial direction and thus allow variations in the swashplate that cannot be easily achieved with conventional manufacturing. For example, the swash plate could have diametrically radially from the inside of extending blind holes for receiving the pins, or the pins could on the inside with the swash plate z. B. integrally connected or made in one piece. The same applies here to a swash plate with only one pin.

To simplify the assembly of a swash plate pre-assembled with the pins, in a further embodiment of the bearing arrangement according to the invention, both guide grooves can extend to one end of the shaft, so that the swash plate with the fully assembled pins projecting radially inwards can simply be pushed on from the end of the shaft can. For this purpose, pins can be threaded into the guide grooves extending to the end of the shaft from the end of the shaft, so that the pins threaded into the extended guide grooves can run up to the storage area, which is limited by the closed end of both guide grooves. The same applies to a bearing arrangement with a guide groove in the shaft and a pin in the swash plate.

In order to reduce the machining or machining effort when producing the groove and/or to avoid weakening the shaft by reducing the wall thickness, the length of the guide grooves can be limited, in which they have the depth predetermined for supporting the swash plate Mounting the swash plate with the radially inwardly projecting pins is followed by a mounting groove on each guide groove, which extends to one end of the shaft and has a smaller depth as the guide groove. The same applies to a storage arrangement with a guide groove in the shaft and a pin in the swash plate. With a mounting groove, the swash plate is pushed on in a similar way to the above-described pushing on with an extended guide groove.

If the bearing arrangement is the bearing arrangement in a surgical instrument in which the shaft is a main shaft, the end to which the extended guide grooves or mounting grooves extend is preferably the proximal end of the main shaft.

In a further embodiment of the bearing arrangement according to the invention, for which the possibility of an axial offset of the swash plate is not necessary or desirable, it is provided that the shaft has a spherical section on which the shaft diameter is widened to form the spherical contour, and that the guide groove / s on the ball section / s. The swash plate, whose pin(s) engages in the guide groove(s), has a receiving recess on its inner side that is at least partially contoured to fit the ball section. Since the guide groove(s) follows the circular contour of the ball section, no extensions of the guide groove(s) or assembly groove(s) to the end of the shaft are required for mounting the swash plate with the pin(s) pointing inwards.

In a variant of the embodiment with a spherical segment, the receiving recess can be spherical in shape corresponding to the spherical segment, whereby the receiving recess acts on both sides in the manner of a joint socket and the coupling is thus completely fixed axially. A two-piece design of the swash plate allows assembly by mounting the swash plate parts on the ball section to complete the swash plate. A two-piece swash plate can be divided in the axial or radial direction. Alternatively, a one-piece swash plate with a spherical receiving recess could be made of a plastic with sufficient elasticity, so that the one-piece swash plate can be pressed onto the spherical section of the shaft in a kind of snap connection.

In an alternative variant to this, the receiving recess has a spherical section and a cylindrical or expanding section, so that the swash plate is only fixed on one side by the spherical section and a mounting ge is made possible on the spherical portion by the cylindrical or flared portion has when pushed onto the shaft in the direction of the spherical portion.

The surgical instrument according to the invention, which has a main shaft which runs coaxially to a—preferably hollow—shank and forms a bearing arrangement with a swash plate, provides in a first embodiment that the bearing arrangement is a bearing arrangement according to the invention.

In this bearing arrangement, the pin pointing radially inwards on the swash plate engages in the guide groove made longitudinally in the main shaft or the two pins arranged diametrically and pointing radially inwards on the swash plate engage in the two guide grooves made diametrically and lengthwise on both sides in the main shaft, to transmit an angle of rotation of the shaft to the swash plate.

The advantageously simple design of the storage arrangement means that procurement, storage and assembly costs can be reduced. In particular, a miniaturization of the surgical instrument is made possible by the compact design of the bearing arrangement, even in the case of large angular offsets.

In a further embodiment, the surgical instrument has an actuating unit arranged at the proximal end of the shaft and a tool tip with a tool arranged at the distal end of the shaft. The tool can be actuated via an actuating element which is mounted so as to be axially displaceable in the shaft, which extends through a longitudinally axial through hole in the main shaft and is operatively connected proximally to the actuating unit. The tool tip can be pivoted relative to the longitudinal axis of the shaft via a joint mechanism, and the joint mechanism is operatively connected to a drive on the proximal side, which has the swash plate in the bearing arrangement according to the invention, which miniaturizes the drive on the proximal side permitted. The spatial orientation of the swash plate in relation to the main shaft caused by movement of the drive on the proximal side causes the tool tip to pivot.

In one embodiment, the joint mechanism can consist of pivoting members arranged at the distal end of the shaft, which are connected to the drive on the proximal side via steering wires running in the longitudinal direction of the shaft, in that the steering wires are mounted on the swash plate, so that a movement of the proximal be good Drive causes a corresponding relative movement of the distal pivoting members and thus pivoting of the tool tip.

If the bearing arrangement according to the invention is used for the surgical instrument according to the invention, then in the embodiment of the bearing arrangement in which the shaft has a spherical section on which the shaft diameter is widened to form the spherical contour and the guide grooves are present on the spherical section, the swash plate has a the ball section at least partially contoured contoured receiving recess on its inside. In the surgical instrument, the spherical section is preferably on the proximal side and the cylindrical or widening section is on the distal side, so that the swash plate is fixed in the distal direction on the ball section and the assembly of the swash ring on the ball section of the shaft is from the proximal end of the shaft can be done. The one-sided fixation here works in the surgical instrument because the swash plate, to which steering wires for moving a distal-side tool tip are fastened, is pulled on one side by the tension of the steering wires and is thus held on the ball section.

In a preferred embodiment, the proximal is term drive as a motorized drive with at least two drive wheels, z. B. driven gears, between which the swash plate is arranged. Furthermore, the swash plate can be coupled to a third gear wheel that meshes with the two driven gear wheels, with a fourth gear wheel that meshes with the two driven gear wheels preferably being arranged on the axis of rotation of the third gear wheel offset by 180° with respect to the third gear wheel so that the toothed chain that is formed is closed to form a toothed ring that ensures an even distribution of force all around.

Other embodiments, as well as some of the advantages associated with these and other embodiments, will become apparent and better understood through the following detailed description with reference to the accompanying figures. Items or parts thereof that are substantially the same or similar may be given the same reference numbers. The figures are only a schematic Dar position of an embodiment of the invention. In the drawings, an embodiment is shown as an example of the invention. The drawings, the description and the claims contain numerous characteristics in combination. The person skilled in the art will expediently also consider the features individually and combine them into further meaningful combinations.

show:

1 shows a schematic perspective side view of a surgical instrument, FIG. 2 shows a perspective detailed view of a swash plate bearing arrangement from the prior art,

3 perspective views a), b), c) of a bearing arrangement according to the invention with a different position of the swash plate in relation to the main shaft, FIG. 4 a plan view of the bearing arrangement according to the invention from FIG. 3c),

5 shows a longitudinal sectional view through the bearing arrangement according to the invention from FIG. 4 along section line A-A,

6 shows a longitudinal sectional view of the bearing arrangement corresponding to FIG. 5 with a position of the swash plate corresponding to FIG. 3a),

Fig. 7 is a longitudinal sectional view of an assembly arrangement for producing the bearing arrangement according to Fig. 6,

8 shows a perspective, partially sectional, detailed view of an embodiment of the bearing arrangement according to the invention with a ball section,

Fig. 9 is a partially sectional plan view of the bearing assembly of Fig. 8,

10 shows a perspective view of the swash plate for an embodiment of the bearing arrangement according to the invention with a ball section corresponding to FIGS. 8 and 9,

11 is a side sectional view through a swash plate having a spherical receiving portion.

Fig. 1 shows schematically a surgical instrument 1 with a hollow shank 2, arranged at the proximal end 3 of the shank 2, shown only schematically Actuate supply unit 4 and arranged at the distal end 5 of the shank 2 tool tip 6 with a tool 7, which is about an axially displaceable in the shaft 2 Actuate supply element 8 can be actuated, which is proximally connected to the actuating unit 4 in Wirkver connection. The actuating unit 4 can be a manually actuated handle or a structural unit designed for robotic use, that is to say it can also be actuated without manual intervention. With the tool 7 the tool tip 6 it can be, for example, a tool provided with jaw parts, as shown in FIG. 1, or an endoscope, an applicator or the like. The tool tip 6 can be pivoted relative to the longitudinal axis 10 of the shank 2 via a joint mechanism 9, the joint mechanism 9 consisting of pivoting members 11 arranged at the distal end of the shank 5 The end 3 of the shaft 2 is connected to a drive 13 arranged such that a movement of the drive 13 at the proximal end causes a corresponding relative movement of the pivoting members 11 at the distal end and thus a pivoting of the tool tip 6 . Even if only the term steering wires 12 is used above and below, steering cables can also be used functionally, which is why the term steering wires 12 used should also be read and understood synonymously as a steering cable.

The axially ver slidably mounted in the shaft 2 actuating element 8 for actuating the tool 7 consisting of two jaw parts, for example, is designed as a push/pull rod in the illustrated embodiments. In the medical instrument 1 according to the invention, the drive 13 for the steering wires 12 can preferably be designed as a motorized drive 13, which has a spatially adjustable swash plate 14 on which the steering wires 12 are mounted in such a way that a preferably motorized drive 13 effected displacement of the swash plate 14 via the steering wires 12 causes a pivoting of the tool tip 6, as z. B.

US Pat. No. 10,105,128 B2 or the swash plate bearing arrangement from FIG.

By using a motorized drive 13 for the spatially adjustable disk 14, it is possible to control the steering wires 12 for pivoting the distal-side pivoting members 11 or the instrument tip 6 precisely, sensitively in the smallest of steps and also reproducibly. In addition, the number of steering wires 12 to be used for a motorized drive 13 is irrelevant. As is known from the prior art according to FIG. 2, the motorized drive 13 can have two drive units with gear wheels 18 and 19, preferably bevel gears, driven by motors, between which the swash plate 14 is arranged. In the surgical instrument 1 according to FIG. 1 (in conjunction with FIG. 2 - prior art - or FIG. 3-11 - inventions to the invention storage arrangement 40) in the shaft 2 is a coaxial to the longitudinal axis 10 of the shaft 2 extending hollow main shaft 21 arranged, which is rotatable about the longitudinal axis 10 of the shaft 2 and extends beyond the proximal end 3 of the shaft 2 to in the area of the motorized drive 13 extends. Within this hollow main shaft 21, the actuating element 8 for actuating the instrument 7 is axially displaceable gela siege.

The steering wires 12 emerging from the shaft 2 at the proximal end 3 of the shaft 2 are guided through steering wire grooves 26 at the distal end of the main shaft 21 and can be fanned out via a serrated lock washer (not shown) arranged non-rotatably on the main shaft 21, thereby increasing the radial spacing of the steering wires 12 is enlarged from the longitudinal axis 10 of the shaft 2. The proximal be tig behind such a serrated lock washer parallel to the longitudinal axis 10 of the shaft 2 running steering wires 12 extend to the swash plate 14 to which the steering wires 12 are fixed. Increasing the radial distance of the steering wires 12 from the longitudinal axis 10 of the shaft 2 not only simplifies the assembly and manufacture of the gear 13 equipped with the swash plate 14, but also reduces the necessary adjustment angle of the swash plate 14 per portion, by a desired amount to achieve high pivot angle of the tool tip 6. However, the increase in the radial distance can also be achieved without a serrated lock washer, in which case the steering wires 12 exiting through the steering wire grooves 26 at the proximal end 3 run directly to the swash plate 14, so that the steering wires are fed to the swash plate 14 at an angle to the longitudinal axis 10. Due to the lower installation space requirement, a variant without a serrated lock washer may be preferred. To fasten the steering wires, the swash plate 14 has an axially parallel through-hole 41 for each steering wire 12, with the steering wires 12 being fastened within the through-holes 41 using grub screws 41" as in Fig. 2 or on the proximal side with a clamping disk 4L, as in Fig. 8 and 9, can be fixed and non-positively connected to the swash plate 14. Alternative forms of attachment of the steering wires to the swash plate also include, for example, welding or crimping or other clamping devices.

As indicated in Fig. 2, the driven gears 18 and 19 are coupled to a third gear 30, which meshes with the two driven gears 18 and 19 and whose axis of rotation D is the central axis A of the driven gears 18 and 19 and the longitudinal axis 10 of the shaft 2 cuts. The third gear 30 is preferably designed as a bevel gear. Through the three meshing gears 18, 19 and 30, each movement of the two driven gears 18 and 19 is transmitted directly to the coupled to the third gear 30 swash plate 14, which is a direct Actuation of the steering wires 12 causes. As can be seen from FIG. 2, the swash plate 14 is mounted in a steering ring 33 which is coupled to the third gear wheel 30 in a rotationally fixed manner. In order to close the toothed chain formed by the toothed wheels 18, 19 and 30 to form a closed toothed ring, which ensures an even circumferential force distribution, a fourth toothed wheel 31 is arranged on the axis of rotation D of the third toothed wheel 30, offset by 180° with respect to the third toothed wheel 30 , Which is in engagement with the two driven gears 18 and 19, wherein the fourth gear 31 is preferably formed as a bevel gear. The swash plate 14 is mounted via a bearing ring 32 in the steering ring 33 , which is coupled in a rotationally fixed manner to the third gear wheel 30 , in order to enable the swash plate 14 to rotate about the longitudinal axis 10 of the shaft 2 . The steering ring 33, which is non-rotatably coupled to the third gear 30, can be rotated freely relative to the fourth gear 31 via a bearing ring 34, so that rotation of the fourth gear 31 about its axis of rotation D does not cause the steering ring 33 and the swash plate 14 to rotate.

The embodiments of the drive 13 described above with reference to Fig. 2 for the spatial alignment of the swash plate 14 for controlling the tool tip by means of the steering wires 12 also apply to a surgical instrument 1 according to the invention, which has a bearing arrangement 40 according to the invention, while the swash plate 14 moves from the standstill 2 for cardanic mounting via two bearing pins 27 offset by 180° from one another on a universal joint disk 28 on the main shaft 21, the universal joint disk 28 being pivotable via two bearing pins 29 offset by 180° from one another on the main shaft 21 is mounted, the bearing pins 27 of the spatially adjustable disk 14 and the La gerstifte 29 of the universal joint disk 28 are offset by 90 ° to each other.

A bearing arrangement 40 according to the invention, which also makes it possible to pivot the swash plate 14 by two degrees of freedom, as a result of which the tool tip 6 can be pivoted in all spatial directions relative to the longitudinal axis 10 of the shaft 2 via the steering wires 12 on the valley side, is structurally much simpler and more compact and easier to assemble. 3 to 7 relate to an example of a first embodiment of a bearing arrangement 40 according to the invention, and FIGS. 8 to 9 show an example of a further embodiment.

The storage arrangement 40 according to the invention of a swash plate 14 on a main shaft 21 according to FIGS. 3 to 6 (Fig. 7 shows a mounting arrangement for this) is for use in a surgical instrument 1 is preferably suitable. The main shaft 21 of the bearing arrangement 40 has, in the area provided for the bearing of the swash plate 14, two guide grooves 22 extending along the shaft 21 and introduced on both sides or diametrically in the shaft 21, into the two diametrically and radially inwardly pointing on the swash plate 14 arranged pins 42 engage, of which only one is indicated for the sake of clarity. As can be seen in Fig. 3, the swash plate 14 mounted in this way can move from the neutral position a), in which the swash plate 14 lies in a plane defined by the axis of rotation A, perpendicular to the longitudinal axis 10, into a position pivoted about the axis of rotation D b) and also in a position c) pivoted about the axis of rotation A. Superimposed movements by pivoting around both axes of rotation A, D are also possible, but not shown. By engaging the pins 42 in the guide grooves 22 can also be a rotation angle of the shaft 21 on the swash plate 14 are transmitted. Although the bearing arrangement 40 shown by way of example with the two diametrical pins each engaging in a guide groove may be preferred, a bearing arrangement according to the invention (not shown) can also have just one inwardly pointing pin on the swash plate, which can engage in a corresponding single guide groove which along the main shaft he stretches.

The bearing arrangement 40 of the swash plate 14 on the main shaft 21 makes it possible for the swash plate 14 to be displaced three-dimensionally relative to the longitudinal axis 10 of the shaft 2 . If, starting from the neutral starting position shown in Fig. 3a, in which the swash plate 14 is aligned perpendicularly to the longitudinal axis 10 of the shaft 2, the gears 18 and 19 are driven in such a way that the gears 18 and 19 rotate in the same direction, causes this rotation of the driven gears 18 and 19 due to the meshing engagement with the third gear 30 and the fourth gear 31 a tilting of the swash plate 14 coupled to the toothed ring about the axis of rotation A, as shown in Fig. 3c. If, starting from the neutral starting position shown in Fig. 3a, the driven gears 18 and 19 are driven in such a way that the gears 18 and 19 rotate in opposite directions, this rotation causes the driven gears 18 and 19 to mesh due to the engagement with the Third gear 30 rotates the ge with the toothed ring coupled swash plate 14 about the axis of rotation D, as shown in Fig. 3b. The tilting of the swash plate 14 about the axis of rotation A or the twisting of the swash plate Disk 14 about the axis of rotation D relative to the longitudinal axis 10 of the shank 2 causes, via the steering wires 12, that the instrument tip 6 is pivoted on the distal side relative to the longitudinal axis 10 of the shank 2 in a corresponding manner. The same applies to a superimposed tilting-rotary movement about both axes A, D.

Both the tilting of the swash plate 14 about the axis of rotation A and the rotation of the swash plate 14 about the axis of rotation D and the superimposed tilting-rotary movement who the engaging in the guide grooves 22 pins 42 of the swash plate 14 he allows. The maximum tilting or twisting or the maximum tilting and rotation angles around the axis of rotation A and D are determined by the length and depth of the guide grooves 22 in conjunction with the inner diameter and thickness of the swash plate 14 in relation to the outer diameter of the shaft 21 and the length of the pins 42 determined. As can be seen in FIG. 5, the maximum tilting is limited by contact of the swash plate 14 or the corresponding pin 42 on the distal end of the guide groove 22. If a larger tilt angle is required or desirable for a swash plate-shaft combination with fixed dimensions, the guide grooves 22 must be lengthened accordingly.

Furthermore, the transmission of a rotational movement of the main shaft 21 about the longitudinal axis 10 of the shank 2 to the swash plate 14 is provided by the bearing arrangement 40 according to the invention, as a result of which the tool tip 6 coupled to the main shaft 21 on the distal side also rotates about the longitudinal axis 10 of the shank 2 rotates. In the event that the swash plate 14 is tilted and/or twisted relative to the longitudinal axis 10 of the shaft 2 during the rotation of the main shaft 21 about the longitudinal axis 10 of the shaft 2, the steering wires 12 fixed to the swash plate 14 run through different control positions, the distal bending of the tool tip 6 remains spatially the same despite the rotation of the tool tip 6 about the longitudinal axis 10 of the shank 2 .

The storage arrangement according to the invention shown in FIGS. 3 to 7 also shows mounting grooves 25, which adjoin the guide grooves 22 on the proximal side up to the end of the shaft 21 and have a smaller depth than the guide grooves 22, so that in comparison to a guide groove that goes through to the end of the shaft (Not shown), the machining effort is reduced, and the remaining wall thickness of the main shaft 21 is increased by the through hole 23. Fig. 7 illustrates the assembly of the swash plate 14 with the rings from the inside of the ring-shaped swash plate 14 radially inwardly projecting pins 42, which is from the proximal end of the shaft when pushing on the swash plate 14 can run in the mounting grooves 25 until the guide grooves 22 are reached (Fig. 6).

Alternatively, non-illustrated embodiments of the bearing arrangement 40 according to the invention are conceivable, in which the guide grooves 22 are extended to the proximal end of the main shaft 21 if the wall thickness of the main shaft 21 and the cutting costs Zer play no role. If neither extended guide grooves 22 nor mounting grooves 25 are provided, the swash plate 14 on the main shaft 21 must be pushed into the area of the guide grooves 22 to mount the bearing arrangement before the pins 42 are inserted into the swash plate 14 to engage with the Provide guide grooves 22. The respective assembly variant can be selected accordingly to the assembly process of the drive 13 of the surgical instrument 1.

To mount the pins 42, the swash plate 14 can have two diametrically radial through-holes 43 (cf. also the exemplary embodiment according to FIGS. 8, 10), so that the pins 42 can be inserted from the outside of the swash plate 14 through the through-hole 43 until they emerge from the inside of the swash plate 14 and protrude radially inward by the desired length. Alternatively, in non-illustrated embodiments, the pins 42 can be fastened to the swash plate 14 in two blind bores running diametrically radially from the inside, which are produced, for example, by an additive manufacturing process or, when using a swash plate made of two parts, are introduced into a respective half ring can. In a further alternative, the pins 42 can be cohesively connected to the swash plate 14 on the inside, e.g. B. be made in one piece.

8 to 10 show examples of an alternative embodiment of a bearing arrangement 40 according to the invention, in which the main shaft 21 has a ball section 24 for the ball-joint bearing of the swash plate 14, on which the guide grooves 22 are present, with this embodiment not having an axial offset of the swash plate 14 allowed. The swash plate 14 has a contoured receiving recess 44 that is at least partially adapted to the ball section 24 and, in the example shown, consists of a spherical section 45 on the proximal side and a cylindrical section 46 on the distal side - malside end of the main shaft 21 allowed. As an alternative to a cylindrical section, a widening section (not shown) can be provided on the distal side. The swash plate 14 is only fixed on one side on the ball section 24 by the spherical section 45 on the proximal side, but is fixed by the tension of the steering wires 12, which are passed through the passage openings 41 here, and are fastened with a clamping ring 41' arranged on the proximal side. held so that the swash plate 14 is fixed in the axial direction.

In Fig. 11 a modification of this embodiment is shown, in which the receiving recess 44 of the swash plate 14 corresponding to the spherical portion 24 is fully formed as a spherical portion 45, so that the ball-and-socket position is fully fixed axially. However, this embodiment requires at least a two-part design of the swash plate 14 in order to allow assembly on the ball section 24, for which two alternatively possible separation or connection planes of the swash plate 14 are indicated by way of example in FIG. 11 by the dashed lines. A separation or connection plane runs perpendicularly to the longitudinal axis 10, so that the swash plate 14 consists of two partial rings that can be separated or connected in the axial direction. A second separation or connection plane, in which the longitudinal axis 10 lies, runs in a radial direction and provides a swash plate 14 which consists of two half rings that can be separated or connected in the radial direction.

In the drawings an embodiment of the invention is shown. The drawings, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into further meaningful combinations. The present invention provides a bearing arrangement 40 for a swash plate 14 on a shaft 21 and a surgical instrument 1 with a main shaft 21 which extends coaxially with a shaft 2 and forms such a bearing arrangement with a swash plate 14 . The location arrangement arrangement 40 is through

- at least one longitudinally extending guide groove 22 present in the shaft 21 and

at least one pin 42 arranged radially inwards on the swash plate 14 is provided. The pin 42 engages in the guide groove 22 so that an angle of rotation of the shaft 21 can be transferred to the swash plate 14 . List of References p

1 medical instrument

2 shaft

3 Proximal End (Shaft)

4 operating unit

5 Distal End (Shaft)

6 tool tip

7 tool

8 actuator

9 Gel enkmechani smu s

10 Longitudinal axis 11 Pivot link 12 Steering wire

13 drive

14 swash plate

18, 19 gear (driven) 21 main shaft 22 guide groove

23 through hole

24 ball section

25 mounting groove

26 steering wire groove

27, 29 bearing pin 28 universal joint washer

30, 31 third, fourth gear 32 steering ring

33, 34 bearing ring 40 bearing arrangement

41, 4 , 41" through hole, fastening washer, grub screw

42 pin

43 location hole

44 receiving recess

45, 46 Spherical cylindrical section

Claims

patent claims

1. Lagemngsanordnung (40) of a swash plate (14) on a shaft (21), characterized in that the storage arrangement (40) by

- at least one longitudinally extending guide groove (22) present in the shaft (21) and

- at least one pin (42) arranged radially inwards on the swash plate (14) is provided, the pin (42) engaging in the guide groove (22) so that an angle of rotation of the shaft (21) can be transferred to the swash plate (14). is.

2. Storage arrangement (40) according to claim 1, characterized in that the storage arrangement (40) through

- two longitudinally extending guide grooves (22) diametrically present in the shaft (21) and

- two pins (42) arranged diametrically and pointing radially inwards on the swash plate (14) are provided, each pin (42) engaging in one of the guide grooves (22).

3. Storage arrangement (40) according to claim 1 or 2, characterized in that the storage arrangement (40) for a surgical instrument (1) is formed, wherein the shaft is a main shaft (21) of the surgical instrument (1), which is a coaxial to a longitudinal axis (10) of the main shaft (21), has an actuating unit (4) at its proximal end (3) and a tool tip (6) with a tool (7) at its distal end (5). which can be actuated via an actuating element (8) which is mounted so that it can move axially in the shaft (2), which extends through a longitudinally axial through bore (23) in the main shaft (21) and is operatively connected proximally to the actuating unit (4).

4. Positioning arrangement (40) according to at least one of Claims 1 to 3, characterized in that a maximum permissible tilting of the swash plate (14) is determined by a length and a depth of the at least one guide groove (22) and/or by a ratio of an outer diameter of the Shaft (21) and an inner diameter of the swash plate is predetermined.

5. Storage arrangement (40) according to at least one of claims 1 to 4, characterized in that

- The at least one guide groove (22) extends to one end of the shaft (21), or

- The length of the at least one guide groove (22) is limited, with the at least one guide groove (22) being followed by a mounting groove (25) which extends to one end of the shaft (21) and has a smaller depth than the guide groove (22).

6. Bearing arrangement (40) according to at least one of claims 1 to 5, characterized in that the shaft (21) has a spherical section (24) on which the at least one guide groove (22) is present, the swash plate (14) having a the spherical portion (24) has at least partially contoured receiving recess (44).

7. Bearing arrangement (40) according to claim 6, characterized in that the receiving recess (44) corresponding to the ball section (24) is spherical, wherein the swash plate (14) is designed in two parts, or the receiving recess (44) has a spherical section ( 45) and a cylindrical or flared portion (46).

8. Surgical instrument (1) with a main shaft (21) running coaxially to a shaft (2) and forming a bearing arrangement with a swash plate (14), characterized in that the bearing arrangement is a bearing arrangement (40) according to at least one of claims 1 until 7 is.

9. Surgical instrument (1) according to claim 8, characterized in that the surgical instrument (1) has an actuating unit (4) arranged at the proximal end (3) of the shaft (2) and an actuating unit (4) at the distal end (5) of the shaft (2 ) arranged tool tip (6) with a tool (7) which can be actuated via an actuating element (8) which is mounted in the shaft (2) in an axially displaceable manner and which extends through a longitudinally axial through bore (23) in the main shaft (21) and on the proximal side is operatively connected to the actuating unit (4), the tool tip (6) being pivotable via a joint mechanism (9) relative to the longitudinal axis (10) of the shank (2), and the joint mechanism (9) having a drive (13 ) is in operative connection, which has the swash plate (14).

10. Surgical instrument (1) according to claim 8 or 9, characterized in that the joint mechanism (9) consists of pivoting members (11) which are arranged at the distal end (5) of the shaft (2) and which can be pivoted in the longitudinal direction of the shaft (2) running steering wires (12) are connected to the proximal-side drive (13) in such a way that a movement of the proximal-side drive (13) causes a corresponding relative movement of the distal-side pivoting members (11) and thus pivoting of the tool tip (6) caused, wherein the steering wires (12) are mounted on the swash plate (14).

11. Surgical instrument (1) according to at least one of claims 8 to 10, characterized in that the proximal side drive (13) is designed as a motorized drive (13) with at least two drive wheels (18, 19), between which the swash plate (14) is arranged.

2. Surgical instrument (1) according to claim 11, characterized in that the swash plate (14) is coupled to a third gear (30) which is in engagement with the two drive wheels (18, 19), wherein preferably on the axis of rotation of the third gear (30) offset by 180 ° to the third gear (30) a fourth gear (31) is arranged, which is in engagement with the two driven gears (18, 19).