DE102012008537B4 - Surgical robot system - Google Patents

Abstract

Cover with a hose-like inner passage for passing through
through a hollow shaft
a robot or
a drive unit (2; 102) for an instrument arrangement that can be fastened, in particular detachably, to a robot of a surgical robot system, the drive unit (2; 102) having at least one rotary drive (7, 8, 9) with a drive shaft, in particular a hollow drive shaft (10, 13, 15; 106, 107, 108), with a coupling part (31, 32, 33; 200, 201, 202; 300, 301, 302) for coupling to a drive shaft of an instrument of the instrument arrangement,
and through an outlet opening (507) of the casing,
wherein the inner leadthrough has a blind plug (502) and a closure ring (503) for fastening to a peripheral region of the inner leadthrough, which becomes free by removing the blind plug (502).

Description

The present invention relates to a surgical robot system with a robot and an instrument arrangement attached thereto, such an instrument arrangement with a drive unit, an instrument and an instrument interface as well as such an instrument interface, as well as a sleeve, in particular such an instrument interface, and a method for applying the same.

Surgical instruments should be as sterile as possible. On the other hand, robots are difficult to sterilize due to factors such as lubricants, drive force, and the like.

From the WO 2009/061915 A2 A robot with an adapter mount is therefore known, to which an adapter of a sterile sheath is attached, which encloses the robot. An instrument is attached to the sterile side, facing away from the robot, whose end effector is actuated by cables in the instrument shaft.

For this purpose, discs, which are mounted side by side in the sterile adapter, are coupled to counter discs integrated into the robot arm. The rotary drives for actuating the counter discs are located in the robot base, and the drive torque is transmitted via cables in the robot arm, making the self-propelled instrument easy to handle.

After WO 2009/061 915 A2 A sterile adapter, a sterile drape with the integrated sterile adapter and a telerobotic surgical system comprising the sterile drape are provided, wherein the adapter, the sterile drape and the system enable the covering of parts of a telerobotic surgical system to maintain a sterile barrier between the sterile surgical field and the non-sterile robotic system and at the same time provide an interface for the transmission of mechanical and electrical energy and signals between a robotic arm and a surgical instrument in the sterile field.

According to US 2007 / 0 016 174 A1, a robot-assisted surgical instrument for controlling the flow of one or more fluids into and out of a surgical site is provided, which may include a housing, a flow control system, a hollow tube and one or more hose connectors.

According to US 2010 / 0 154 578 A1, actuating elements such as cables or push rods in an instrument are used to manipulate an end effector or distal end of the instrument, wherein each actuator element extends within a tubular housing and either the tubular housing is rotated axially about the actuator element or the actuator element is rotated axially within the tubular housing to reduce at least one force that counteracts an axial force exerted by the actuator element or its movement.

US 2011/0 295 270 A1 relates to a surgical instrument for use with a robotic system, having a control unit and a shaft portion comprising an electrically conductive elongate element attached to a portion of the robotic system, the elongate element being configured to transmit control movements from the robotic system to an end effector.

An object of the present invention is to provide an improved surgical robot system.

This object is achieved by a surgical robot system having the features of claim 10. Claim 5 protects an instrument assembly of such a surgical robot system, claim 3 protects an instrument interface of such an instrument assembly, and claims 1 and 2 respectively protect a cover, in particular for such an instrument interface, and a method for using the same. The subclaims relate to advantageous developments.

Surgical robot system

A surgical robot system according to one aspect of the present invention comprises one or more robots. In one embodiment, a robot can have six or more joints, in particular rotary joints, wherein more than six joints can enable advantageous positioning of the redundant robot. In one embodiment, the robot(s) have a controller. In this case, several robots can have a common central controller or individual controllers, which can be used for more compact presentation. Position is also collectively referred to as a robot controller. In one embodiment, a robot can be arranged on an operating table, in particular releasably attached.

An instrument assembly according to an aspect of the present invention explained below is attached to one or more robots of the surgical robot system. In one embodiment, an instrument assembly is detachably attached to a robot, in particular in a form-fitting, frictional, and/or magnetic manner, in particular electromagnetically. In one embodiment, the instrument assembly, in particular a drive unit of the instrument assembly, has a housing that is attached, for example, screwed, latched, or clamped, to an outer side of the robot, in particular to a robot (end or tool) flange. Additionally or alternatively, in particular an instrument interface and/or an instrument of the instrument assembly can be attached to the outer side of the robot, in particular to a robot (end or tool) flange.

Instrument arrangement

An instrument assembly according to one aspect of the present invention is configured for attachment to a robot or is designed as a robot-guided instrument assembly. It comprises a drive unit, an instrument, and an instrument interface according to one of the aspects of the present invention explained below.

By incorporating the drive unit into the instrument assembly itself, which is preferably designed to be portable as a whole, the transfer of drive forces from the robot itself to the instrument can be advantageously eliminated, allowing the robot to be constructed in a smaller size, which can particularly facilitate the cooperation of several slender robots in a limited operating area. Furthermore, the drive unit can be easily adapted to different instruments or even replaced. It is preferably designed as a standalone module or module independent of the robot.

In one embodiment, an instrument arrangement comprises two or more different drive units and/or two or more different instruments, which can be selectively connected, in particular in a modular manner, to an instrument or drive unit to form an instrument arrangement attached to the robot. Different drive units or instruments can differ, in particular, in the number and/or performance of actuated degrees of freedom. For example, a drive unit with three actuated degrees of freedom can be selectively connected to an instrument with one or two actuated degrees of freedom and two or one non-actuated, i.e., unused or blind, degrees of freedom, and to instruments with three actuated degrees of freedom that have different end effectors.

The instrument and drive unit are detachably connected to one another, with an instrument interface being arranged between the drive unit and the instrument. The instrument and drive unit can in particular be fastened to one another and/or to the instrument interface arranged therebetween in a form-fitting, frictional, material-fitting and/or magnetic manner, preferably electromagnetically. In particular, the instrument interface can be screwed, latched, clamped or even glued to the drive unit and/or the instrument, with the adhesive point being designed as a predetermined separation point. Additionally or alternatively, the drive unit can be screwed, latched or clamped to the instrument. In one embodiment, the instrument interface has a dimensionally stable flange for fastening the drive unit and/or the instrument. In one embodiment, the drive unit is arranged at a proximal end of the instrument, or end effector-distant end.

drive unit

A drive unit according to one aspect of the present invention comprises one or more, in particular three or four, rotary drives, each with at least one drive shaft. In one embodiment, one or more rotary drives of the drive unit each comprise one or more electric motors, in particular DC or AC motors, with a stator and a rotor. Additionally or alternatively, one or more rotary drives of the drive unit can each comprise one or more hydraulic motors and/or piezo drives, which can drive the respective drive shaft(s) or apply a torque to them. The drive shaft can in particular be a rotor or runner of an electric and/or hydraulic motor. In one embodiment, a rotary drive comprises a preferably coaxial gear, in particular an epicyclic gear, preferably a planetary or harmonic drive, wherein the drive shaft can be an output shaft of the gear. In another embodiment, a rotary drive is designed as a direct drive. In the present case, this is understood in particular to mean that the drive shaft is directly by a drive torque, in particular one generated hydraulically, electrically, and/or (electro)magnetically, without an intermediate gear. In particular, such a direct drive can be designed to be self-locking. This advantageously allows the instrument to be removed from a patient with the flanged drive unit. Additionally or alternatively, a rotary drive can have a sensor, in particular a coaxial one, in particular a speed and/or torque sensor on the input and/or output side.

The drive shaft has a coupling part for coupling to a drive shaft of the instrument, which coupling part is rotationally fixed to the drive shaft. In one embodiment, it can be axially fixed to the drive shaft, in particular integral with it. In another embodiment, the coupling part is arranged axially displaceably on the drive shaft, in particular in a form-fitting manner, for example by means of a key, a spline, a toothed or polygonal shaft profile, or the like. In a further development, the coupling part is axially preloaded, in particular by a spring means, against the instrument interface attached to the drive unit or the instrument attached to the drive unit. This can, in particular, compensate for an axial tolerance and/or represent a contact force for a frictional connection.

One or more drive shafts are designed as hollow shafts in one embodiment. In one embodiment, the drive unit has one or more drive shafts, each of which is arranged, in particular mounted, concentrically or coaxially in a surrounding hollow drive shaft. For the sake of compactness, the drive shaft that is arranged in another drive shaft is referred to as the inner drive shaft, and the other drive shaft is referred to as the outer drive shaft. If, for example, the drive unit has three drive shafts in one embodiment, the innermost drive shaft, which can also be designed as a hollow drive shaft, forms an inner drive shaft, the middle drive shaft surrounding it forms an outer drive shaft and at the same time a (further) inner drive shaft, and the outermost drive shaft surrounding it forms a (further) outer drive shaft. In the same way, the drive unit can also have four or more concentric hollow drive shafts.

In one embodiment, one or more rotary drives are arranged coaxially to their respective drive shaft, in particular a common axis of rotation of coaxial drive shafts. In particular, one or more rotary drives can be arranged in alignment one behind the other. Likewise, one or more rotary drives can be arranged parallel to their drive shafts, in particular a common axis of rotation of coaxial drive shafts, offset in the radial and/or circumferential direction, and coupled to them, in particular via a spur gear or friction gear. Likewise, one or more rotary drives can be arranged at an angle, in particular at right angles, to their respective drive shaft, in particular a common axis of rotation of coaxial drive shafts, and coupled to them, in particular via a worm gear, screw gear, or crown gear.

The drive unit can be connected to a power source and/or the controller wirelessly or via a wired connection. In one embodiment, the casing of the instrument interface described below also at least partially encloses a power and/or signal line of the drive unit.

instrument

An instrument according to one aspect of the present invention has an instrument shaft, at the distal end of which, or the end facing away from the drive unit, a single-part or multi-part end effector can be arranged, in particular a scalpel, forceps or scissors legs or the like.

In one embodiment, the instrument is an endo- or minimally invasive surgical instrument ("MIS"), in particular an endoscopic instrument, for example, laparoscopic or thoracoscopic. In particular, the instrument shaft can be designed or configured to be inserted into the patient and actuated there through an inlet that preferably substantially corresponds to the outer diameter of the instrument shaft, in particular through a trocar.

The end effector can have one or more degrees of freedom. In particular, one or more parts of the end effector can each have one or two degrees of rotational freedom around axes of rotation that are preferably perpendicular to the shaft axis. For example, a two-part end effector can represent a pair of pliers or scissors whose legs pivot in opposite directions around the same axis of rotation.

To actuate the end effector, the instrument has one or more drive shafts, in particular one drive shaft for actuating each degree of freedom, in one embodiment therefore in particular one, two or three drive shafts.

The drive shaft has a coupling part for coupling to a drive shaft of the drive unit, which coupling part is rotationally fixed to the drive shaft. In one embodiment, it can be axially fixed to the drive shaft, in particular formed integrally with it. In another embodiment, the coupling part is arranged axially displaceably on the drive shaft, in particular in a form-fitting manner, for example by means of a key, a spline, a toothed or polygonal shaft profile, or the like. In a further development, the coupling part is axially preloaded, in particular by a spring means, against the instrument interface attached to the instrument or the drive unit attached to the instrument.

In one embodiment, one or more drive shafts are designed as hollow shafts. In one embodiment, the drive unit has one or more drive shafts, each of which is arranged, in particular mounted, concentrically or coaxially in a surrounding hollow drive shaft.

By designing the (innermost) drive shaft of the instrument as a hollow drive shaft, one embodiment advantageously allows for the insertion or passage of an additional instrument.

In one embodiment, the coupled drive shafts of the drive unit and instrument are aligned with each other. In one embodiment, the drive shaft(s) are arranged coaxially, in particular aligned or offset parallel to the instrument shaft. This allows a radially compact design to be achieved in one embodiment. In another embodiment, the drive shaft(s) are arranged at an angle, in particular at a right angle, to the instrument shaft. This allows the drive unit to be arranged at an angle, in particular at a right angle, to the instrument shaft.

In one embodiment, the instrument has a conversion gear on the instrument side for converting the rotation of one or more drive shafts into a corresponding translation of one or more traction and/or thrust means. A traction means can comprise one or more, particularly counter-rotating, rope, belt, or band drums, and a traction and/or thrust means can comprise one or more, particularly counter-rotating, pull and/or push rods.

In one embodiment, the conversion gear has a slotted guide, in particular one for each of one or more drive shafts of the drive unit. According to one embodiment, a slotted guide comprises a sliding sleeve which is mounted in a rotationally fixed and axially displaceable manner relative to the instrument shaft, in particular on the instrument shaft or a surrounding hollow drive shaft. In one of the sliding sleeve and the drive shaft, a slotted guide or groove is formed, in particular inclined against the axial direction, in which a fitting element, in particular a feather key, is guided in a form-fitting manner by the other of the sliding sleeve and the drive shaft. In this way, a rotation of the drive shaft is converted into an axial translation of the sliding sleeve, which can thus actuate in particular a pulling and/or pushing means.

If, in one embodiment, a drive shaft is mounted in a hollow drive shaft, in a further development, a sliding sleeve of a slotted guide coupled to a drive shaft can simultaneously form a radial bearing, in particular a floating bearing, between the slotted guide and an adjacent drive shaft. A fixed bearing of a drive shaft is preferably arranged at a proximal end of the instrument shaft facing the drive unit.

In one embodiment, the transmission gear is arranged in a half of the instrument shaft facing the drive unit, or the proximal half. In another embodiment, the transmission gear is arranged in a half of the instrument shaft facing away from the drive unit, or the distal half. This advantageously allows the actuation to be transmitted over a large area of the instrument shaft by the traction and/or thrust means or by the drive shafts.

Additional instrument

According to one aspect of the present invention, an instrument arrangement comprises an additional instrument which is inserted or guided, in particular detachably, through the instrument of the instrument arrangement, in particular a guide tube of the instrument, in particular inserted with radial play or a radial fit. For this purpose, the additional instrument can be tubular in one embodiment and rigid or flexible. Accordingly, in one embodiment, the instrument can comprise a guide tube, particularly a rigid one, which can be arranged, particularly centrally, in the instrument shaft and/or can extend—at least substantially—over the entire inner length of the instrument shaft. In a further development, an (innermost) hollow drive shaft of the instrument can function as a guide tube or form a guide tube.

The additional instrument can be designed as a guide for gaseous and/or liquid media, in particular as a suction and/or supply passage, and/or as an electrical and/or optical fiber, for example to remove or supply rinsing or water jet surgical media, in particular under negative or positive pressure, to guide laser and/or illumination light and/or current into the patient and/or to guide optical and/or electrical signals out of the patient.

In one embodiment, the additional instrument can be inserted through the instrument on a side of the instrument interface facing away from the drive unit, so that it advantageously does not need to be sterilely separated from the drive unit. In another embodiment, the additional instrument is inserted through the drive unit, in particular through an (innermost) hollow drive shaft of the drive unit.

In addition or alternatively to the additional instrument, a drive means for actuating an end effector can be inserted, in particular detachably, through the instrument of the instrument assembly, in particular an (innermost) hollow drive shaft of the instrument, in particular inserted with radial play or a radial fit. For this purpose, the drive means can be tubular in one embodiment and can be rigid or flexible. The drive means can in particular comprise one or more pulling and/or pushing means and/or one or more rotating shafts.

Instrument interface

An instrument interface according to one aspect of the present invention comprises a sheath that encloses the drive unit, in particular in a hermetically or sterile manner. In one embodiment, the sheath is flexible, in particular film-like. In one embodiment, the sheath is sterile or sterilizable on the outer side facing away from the drive unit.

In this way, the drive unit, which may be difficult to sterilize due to abrasion, lubricants, temperature- and/or moisture-sensitive components or the like, can be sterilely shielded from the operating environment, with the actuation being transmitted through or via the interface into the instrument, which is advantageously easy to sterilize.

In one embodiment, coupling parts of one or more drive shafts of the drive unit and corresponding, in particular coaxial, drive shafts of the instrument are magnetically coupled to one another. In this case, in particular, the instrument interface can be formed by a simple foil, with an air gap preferably formed between the magnetically coupled coupling parts.

In one embodiment, the instrument interface has one or more rotatable intermediate elements which are designed to be coupled, in particular frictionally or positively, to a coupling part of a drive shaft of the drive unit and a coupling part of a drive shaft of the instrument when the interface is arranged between the drive unit and the instrument, in particular is fastened to the drive unit and/or instrument.

The arrangement of the intermediate elements preferably corresponds to the arrangement of the drive shafts or their coupling parts. If, in one embodiment, the drive shafts of the drive unit and/or instrument are concentric, the intermediate elements are also arranged concentrically to one another, wherein, as explained above, a respective, in particular annular, inner intermediate element is preferably arranged, in particular mounted, concentrically in an outer annular intermediate element. In a further development, the intermediate elements are mounted in a sealed manner, for example by bearing rings which have labyrinth seals or the like. In this case, sealed is understood to mean sterile in the medical sense, in particular sealed in such a way that solid, preferably also liquid, and in particular also gaseous elements of a predetermined size can overcome the seal at most in a predetermined maximum quantity or rate, which can also be zero.

The instrument interface can have a dimensionally stable flange for fastening the drive unit and/or the instrument, in which the intermediate elements are rotatably mounted, in particular in a sealed manner.

For frictional coupling, intermediate elements and coupling parts of the drive unit and/or instrument can have contact surfaces that touch one another when the instrument interface is arranged between the drive unit and the instrument and the instrument and drive unit are connected directly and/or via the instrument interface. For positive coupling, such contact surfaces can have interengaging projections and recesses or complementary shoulders. In particular, one or more projections or shoulders can be arranged on one of a coupling part and an intermediate element, which engage in recesses or complementary shoulders in the other of the coupling part and the intermediate element in a positive-locking manner when the instrument interface, in particular a dimensionally stable flange of the instrument interface, is arranged on the drive unit or the instrument. The coupling part and intermediate element can preferably have intermeshing spur gears, in particular Hirth gears.

The friction or form-fitting contact surfaces can be conical in one embodiment. This advantageously allows for self-centering and/or, particularly in combination with axially displaceable, preferably preloaded, coupling parts, compensation for axial tolerances.

In one embodiment, the sheath has an internal passage for an additional instrument inserted through the instrument and the drive unit of the instrument assembly. This internal passage can be tubular and extend through an inner hollow drive shaft of the drive unit. In a further development, it is sealed, in particular rotatably, to an inner intermediate element of the instrument interface coupled to the hollow drive shaft.

In a further development, the internal feedthrough has a blind plug and a closing ring. In an initial or assembled state, the blind plug is attached to one end of the internal feedthrough, closes it, and covers a peripheral area of the internal feedthrough. The blind plug can then be pulled through the drive unit so that it exits through an outlet opening in the sheath and can be removed. The closing ring can then be attached to the peripheral area of the internal feedthrough that was exposed by removing the blind plug and also close the outlet opening of the sheath. In this way, a torus-shaped sheath with a sterile outer surface can be provided, in whose annular space the drive unit is arranged and thus sterilely separated from the surgical environment, and whose through opening is available for the introduction of the additional instrument.

The above-described development is particularly suitable for the above-described drive unit with a hollow drive shaft. It can also be used for the, in particular sterile, encasing of a robot with a tool flange having a hollow shaft. In this case, (sterile) encasing is understood to mean, in particular, a partial or complete or all-round, particularly hermetic, covering or enclosing.

According to one aspect of the present invention, a sleeve, which in particular can have one or more features of the above-described sleeve of the instrument interface, generally has a hose-like inner feedthrough for passing through a hollow shaft of a robot or of a drive unit explained above and through an outlet opening of the sleeve, wherein the inner feedthrough has a blind plug and a one-part or multi-part closing ring for fastening to the outlet opening and a, in particular outer, circumferential or jacket surface area of the inner feedthrough, which is released by removing the blind plug. The inner feedthrough can in particular be rotatably mounted on the sleeve or formed integrally therewith. It can in particular be rigid or flexible. For a more compact representation, a rigid tubular inner feedthrough is also generally referred to as hose-like.

To enclose the robot or drive unit, the inner bushing, fitted with the blind plug, is first inserted through the hollow shaft and the outlet opening of the casing. The blind plug, which preferably has a closed outer face and/or a tubular outer surface, prevents contamination of the interior of the tubular inner bushing and the peripheral area of the inner bushing covered by it. Similarly, the inner bushing can also The plug must first be sealed at the front, with the sealing area then being separated. To facilitate insertion, the blind plug can have a rigid or flexible insertion aid, in particular a cord or rod.

The blind plug is then removed, and the sealing ring is attached to the peripheral area of the inner feedthrough that has been exposed by the removal of the blind plug. As described above, the sealing ring, which can be rigid or flexible, can be attached to the outlet opening of the casing in a further development, closing it off except for the inner feedthrough. A part of the sealing ring attached to the peripheral area of the inner feedthrough can, in particular, be rotatably mounted on a part of the sealing ring attached to the outlet opening of the casing, or can be formed integrally or in one piece with the latter.

• 1: einen Teil einer Instrumentenanordnung eines Chirurgierobotersystems nach einer Ausführung der Erfindung in einem perspektivischen Schnitt;
• 2: ein instrumentenseitiges Umsetzungsgetriebe nach einer weiteren Ausführung der vorliegenden Erfindung;
• 3: das Umsetzungsgetriebe der 2 in einem anderen perspektivischen Schnitt;
• 4: einen Schnitt einer Kegelkupplung einer Instrumentenanordnung nach einer Ausführung der vorliegenden Erfindung;
• 5: weitere Ausführungen einer solchen Kegelkupplung;
• 6: eine Wellenkupplung einer Instrumentenanordnung nach einer Ausführung der vorliegenden Erfindung;
• 7: einen Schnitt dieser Wellenkupplung der 6;
• 8: eine Magnetkupplung einer Instrumentenanordnung nach einer Ausführung der vorliegenden Erfindung;
• 9: die Magnetkupplung der 8 in einem Schnitt;
• 10: in zwei perspektivischen Ansichten ein Umsetzgetriebe nach einer Ausführung der vorliegenden Erfindung;
• 11: einen vergrößerten Schnitt des Umsetzgetriebes der 10;
• 12: ein Instrument nach einer Ausführung der vorliegenden Erfindung mit einem distalen Umsetzgetriebe in einer perspektivischen Gesamtansicht (oben) bzw. einem vergrößerten Teilschnitt (unten);
• 13: eine Instrumenten-Schnittstelle nach einer Ausführung der vorliegenden Erfindung;
• 14: die Instrumenten-Schnittstelle der 13 mit verbundenem Blindstopfen;
• 15: die Instrumenten-Schnittstelle der 14 mit entferntem Blindstopfen;
• 16: die Instrumenten-Schnittstelle der 15 mit verbundenem Abschlussring;
• 17: die Instrumenten-Schnittstelle der 16 mit ankoppelndem Instrument;
• 18: eine Instrumentenanordnung mit einem eingeführten Zusatz-Instrument nach einer Ausführung der vorliegenden Erfindung;
• 19: einen Teil eines Instruments einer Instrumentenanordnung nach einer weiteren Ausführung der vorliegenden Erfindung;
• 20: einen Teil eines Instruments einer Instrumentenanordnung nach einer weiteren Ausführung der vorliegenden Erfindung; und
• 21A, 21B: ein Umhüllen eines Roboters mit einer Hülle nach einer Ausführung der vorliegenden Erfindung.

The peripheral area of the internal feedthrough, which was exposed by removing the blind plug, was protected from contamination by the blind plug during passage. In this case, fastening to the peripheral area is understood to mean fastening in such a way that the peripheral area, viewed in the longitudinal direction of the internal feedthrough, is completely or partially covered by the cover ring. The peripheral area exposed by removing the blind plug can extend longitudinally beyond the cover ring on one or both sides. Likewise, in addition to the peripheral area exposed by removing the blind plug, or a portion of this peripheral area, the cover ring can also cover a peripheral area of the internal feedthrough that was not previously covered by the cover ring. Further advantages and features emerge from the dependent claims and the exemplary embodiments. The drawing shows, partly schematically:

• 1 : a part of an instrument arrangement of a surgical robot system according to an embodiment of the invention in a perspective section;
• 2 : an instrument-side conversion gear according to a further embodiment of the present invention;
• 3 : the implementation gear of the 2 in a different perspective cut;
• 4 : a section of a conical coupling of an instrument assembly according to an embodiment of the present invention;
• 5 : further designs of such a cone clutch;
• 6 : a shaft coupling of an instrument assembly according to an embodiment of the present invention;
• 7 : a section of this shaft coupling of the 6 ;
• 8 : a magnetic coupling of an instrument arrangement according to an embodiment of the present invention;
• 9 : the magnetic coupling of the 8 in one cut;
• 10 : in two perspective views a conversion gear according to an embodiment of the present invention;
• 11 : an enlarged section of the transfer gear of the 10 ;
• 12 : an instrument according to an embodiment of the present invention with a distal transfer gear in a perspective overall view (top) and an enlarged partial section (bottom);
• 13 : an instrument interface according to an embodiment of the present invention;
• 14 : the instrument interface of the 13 with connected blind plug;
• 15 : the instrument interface of the 14 with the blind plug removed;
• 16 : the instrument interface of the 15 with connected end ring;
• 17 : the instrument interface of the 16 with coupling instrument;
• 18 : an instrument arrangement with an inserted additional instrument according to an embodiment of the present invention;
• 19 : a part of an instrument of an instrument arrangement according to a further embodiment of the present invention;
• 20 : a part of an instrument of an instrument arrangement according to a further embodiment of the present invention; and
• 21A , 21B : covering a robot with a cover according to an embodiment of the present invention.

1 shows a part of an instrument arrangement of a surgical robot system according to an embodiment of the invention in a perspective section.

The instrument assembly comprises an instrument 1, a drive unit 2 connected thereto, and an instrument interface with a sterile sheath 5 arranged between the drive unit and the instrument.

In this embodiment, the rotational axes of the drive unit coincide with a shaft axis of the instrument. This concept is particularly suitable for instruments actuated with push/pull rods.

The sterile surgical instrument 1 is on the 1 left, the drive unit 2 on the in 1 right side. The instrument 1 is mechanically detachably connected to a housing 6 of the drive unit 2 via a connecting flange 4 at a proximal end of the instrument shaft 3. The drive unit 2 is surrounded by a sterile sheath 5 to prevent contamination of the surgical site.

In this exemplary embodiment, the housing 6 of the drive unit 2 contains three independent rotary drives, each with a drive shaft 10, 13, or 15 and an associated electric motor 7, 8, or 9. The drive shafts 10, 13, and 15 are designed as hollow shafts and arranged coaxially with one another. The drive shaft 10 is fully supported at a bearing point 11 in the housing 6. The inner drive shaft 13 is supported by a bearing 12 in the drive shaft 10, and the drive shaft 15 is supported by a bearing 14 in the drive shaft 13. This concept advantageously enables a very compact design of the detachable instrument interface, especially in the radial direction.

In a multi-robot application, the risk of collisions between individual robots can be significantly reduced due to the smaller permissible minimum distance between the instruments.

The symbolic representations of electric motors 7, 8, and 9 include additional components required for controlled operation, such as gears and/or sensors. Preferred designs are concentrically arranged motor units, which can be implemented either as direct drives or as motors with downstream reduction gears, such as planetary gears or harmonic drive gears.

In a modification not shown, the rotary drives can have radially offset electric motors, each driving the drive shafts with a spur gear or friction gear, or orthogonally offset electric motors, each driving the drive shafts with a worm gear, helical gear or crown gear.

The nested drive shafts 10, 13, and 15 are continued on the instrument side in the form of drive shafts 16, 17, and 18, respectively, which are also designed as hollow shafts and arranged coaxially with one another. The instrument-side drive shafts 16, 17, and 18 are mounted as fixed-loose bearings, with fixed bearings 28, 29, and 30 located at the proximal end of the instrument shaft 3. Shaft 16 is radially and axially supported at the bearing point 28 in the instrument shaft 3. The internal drive shaft 17 is supported by the bearing 29 in the drive shaft 16, and the drive shaft 18 is supported by the bearing 30 in the shaft 17. Sliding sleeves 23, 24 and 25 act as floating bearings, which are also components of an instrument-side conversion gear 22 for converting the rotary drive movement into a translatory movement of the pulling and/or pushing means 26, 39 or 40 (cf. 10 ). These ultimately transfer the drive movement to the instrument or end effector degrees of freedom at the distal end of the instrument shaft 3.

1 shows only one pulling and/or pushing means 26 as an example, although a separate transmission element is provided for each degree of freedom of the instrument.

Examples of such pulling and/or pushing devices are cable pulls, Bowden cables or pull/push rods.

A coupling mechanism is provided to connect the drive shafts 10, 13 and 15 of the drive unit with the instrument-side drive shafts 16, 17 and 18, which also represents a sterile barrier between the instrument and the non-sterile drive unit. 1 The clutch shown as an example is a cone clutch that transmits the drive torque by friction or form fit.

This design principle also allows the drive shafts 15 and 18 located internally in the coaxial arrangement to be designed as hollow shafts. This leaves sufficient space in the center of the instrument shaft 3 to accommodate additional drive means, such as a Bowden cable, a rotary shaft with a flexible section in the area of a multiple joint for driving an end effector, and/or an additional instrument, in particular an electrical cable, a hose, or the like. Another possible application of this design principle is the insertion of special surgical instruments through the center of the instrument shaft.

In order to ensure the sterility of the elements passing through the center of the instrument also in the area of the drive unit 2, the sterile barrier extends with an internal passage in the form of a sterile guide tube 27 through the entire drive unit 2, as described below.

2 shows an instrument-side conversion gear 100 according to a further embodiment of the present invention, in which the drive shaft and shaft axes are orthogonal. This arrangement is particularly suitable for instruments actuated by cable pulls. However, it can also be used for instruments with pull/push rods, in that the instrument-side gear for converting the rotation of a drive shaft into a translation of a pulling and/or pushing means can be implemented, for example, as a slider-crank mechanism.

At the proximal end of the instrument 101 is a housing 104, which is permanently connected to the instrument shaft 103. The instrument 101 is connected at the proximal end to the drive unit 102 (the housing of which is not shown) via a sterile barrier 105. The drive shafts 106, 107, and 108 are arranged coaxially in the drive unit 102 to achieve the most compact dimensions possible. They continue on the instrument side as cable pulleys 109, 110, and 111, respectively. The shaft sections are connected by sterile coupling intermediate segments 116, 117, and 118, which are rotatable relative to each other.

A coupling intermediate element 118 of the external drive shaft 106 is connected to the sterile barrier 105 and rotatably mounted therein. In the exemplary embodiment, the drive shafts of the drive unit and the instrument are positively coupled by means of a spur gear coupling, which, with reference to 6 is described in more detail.

The cable pulleys 112, 113, and 114, which actuate the instrument degrees of freedom, are wound around the instrument-side cable pulleys or drive shafts 109, 110, and 111, respectively, so that the force flow between the drive shafts 106, 107, and 108 and the instrument degrees of freedom is closed. Optionally, a pipe feedthrough 115 can be provided, which can be used, for example, to guide an additional instrument, in particular media lines, to the distal end of the instrument shaft 103.

Detachable coupling with sterile barrier for at least one rotary drive train. To connect the instrument to the drive unit, an easily detachable coupling mechanism is provided, which also represents the sterile barrier between the instrument and the non-sterile drive unit.

4 shows in a section the cone clutch of the embodiment of the 1 With sterile barrier. The coupling assembly transmits the drive torque from the drive shafts 10, 13, and 15 to the instrument-side drive shafts 16, 17, and 18 by frictional or positive engagement. Coupling parts in the form of external cones 34, 35, and 36 are arranged at the proximal ends of the instrument-side hollow shafts 16, 17, and 18, which are firmly connected to the respective hollow shaft. Coupling parts 31, 32, and 33 with internal cones are arranged at the distal ends of the drive shafts 10, 13, and 15. The shaft ends are connected via conical intermediate elements 19, 20, and 21, respectively, which act as a sterile barrier. These elements are sealed to each other and also to the sterile barrier 5. These connections are intended solely to facilitate handling during installation of the sterile barrier, but otherwise allow all movements of the intermediate elements required for their function, in particular rotation with the drive shafts. At the same time, these intermediate elements 19, 20 and 21 represent a gap or labyrinth seal between the coupling parts.

The coupling parts 31, 32, and 33 arranged on the drive shafts 10, 13, and 15 are each connected to a shaft in a rotationally fixed but axially movable manner, for example, by a toothed or polygonal shaft profile. Thus, the axial preload required for power transmission can be applied, for example, by springs acting on the drive-side coupling parts. At the same time, any possible axial misalignment between the drive-side and instrument-side shaft sections is compensated.

Instead of the combination of drive-side inner cones and instrument-side outer cones, further arrangements are conceivable for each pairing of an inner and an outer drive shaft of the drive unit and instrument, which in 5 outlined are: Coupling part 31/32/33,34/35/36 5 top left 5 top right 5 bottom left 5 bottom right inner hollow drive shaft of the drive unit inner cone Outer cone inner cone Outer cone inner hollow drive shaft of the instrument inner cone Outer cone inner cone Outer cone outer hollow drive shaft of the drive unit Outer cone inner cone inner cone Outer cone outer Outer cone inner cone inner cone Outer cone Hollow drive shaft of the instrument

6 shows a shaft coupling with sterile barrier, which transfers the drive torques positively via spur gears, for example a Hirth gear, from the drive shafts 10, 13 and 15 to the instrument-side drive shafts 16, 17 and 18, 7 a cross-section of this shaft coupling. The shaft coupling can be used instead of the conical coupling of the 4 , 5 especially with an instrument arrangement according to 1 or 2 , 3 be provided.

For this purpose, spur gears 203, 204, 205 are applied to the proximal coupling parts of the instrument-side hollow shafts 16, 17, and 18, which are firmly connected to the respective hollow shaft. Coupling parts in the form of sliding sleeves with spur gears 200, 201, 202 are arranged at the distal ends of the drive shafts 10, 13, and 15. The shaft ends are connected via sleeve-like intermediate elements 206, 207, and 208 with spur gears on both sides, which act as a sterile barrier. The intermediate sleeves 206, 207, and 208 are connected to each other and to the sterile barrier 5 by the retaining rings 209, 210, and 211. The internal feedthrough or sterile guide tube 27 is also connected to the innermost intermediate sleeve 208 in this way, so that the entire assembly represents a sterile barrier with gap seals. The intermediate sleeves 206, 207, and 208 serve only to facilitate handling during installation of the sterile barrier, but otherwise allow all movements necessary for its function. They function as gap or labyrinth seals.

The sliding sleeves 200, 201, 202 arranged on the drive shafts 10, 13, and 15 are each connected to the shafts in a rotationally fixed but axially movable manner, for example, by a toothed or polygonal shaft profile. Thus, the axial preload required for power transmission can be applied, for example, by springs acting on the sliding sleeves 200, 201, 202. At the same time, any possible axial misalignment between the drive-side and instrument-side shaft sections is compensated.

Another variant of a shaft coupling with sterile barrier is the 8 The shaft coupling can be used instead of the conical or shaft coupling of the 4 to 7 especially with an instrument arrangement according to 1 or 2 , 3 be provided.

Coupling parts in the form of magnetic rings 200, 201, and 202 are fixed to the distal ends of drive shafts 10, 13, and 15, respectively. Similarly, coupling parts in the form of magnetic rings 203, 204, and 205 are fixed to the instrument-side hollow shafts 16, 17, and 18, respectively. All magnetic rings 200 to 205 are magnetized sector by sector and aligned with a preferably small axial spacing or air gap to enable the highest possible drive torque to be transmitted. The magnitude of the transmittable torque depends not only on the air gap but also on the magnetic field strength and the number of magnetic sectors.

9 shows a cross-section of the magnetic coupling with sterile barrier. The magnetic rings are aligned with minimal axial spacing to transmit the highest possible drive torque. An advantageous feature of this coupling principle is the simple design of the sterile sleeve 5. Due to the small axial air gap of the magnetic coupling, a simple film can be used and does not require a special molded part.

Converting the rotation-translation movement type to the instrument side: In one embodiment of the present invention, exclusively rotary drives are used. However, due to the limited space in the instrument shaft, the drive trains in robot-guided surgical instruments predominantly use cables or push/pull rods to transmit the drive movements to the distal end of the instrument. Therefore, after the separable instrument interface described above, an instrument-side conversion gear 22 is provided to convert the rotary drive movement into a translatory movement of the cables or push/pull rods.

10 shows, in two perspective views, a conversion gear 22 according to an embodiment of the present invention, in which a separate sliding sleeve is provided for each drive shaft. In the case shown here, the three sliding sleeves 23, 24 and 25 convert the rotation of the drive shafts 16, 17 and 18 into a translation of the pulling and/or pushing means 26, 39 and 40. The sliding sleeves 23, 24 and 25 also function as distal loose bearings for the hollow shafts 16, 17 and 18, respectively. The sliding sleeves themselves only have one translational degree of freedom, which allows displacement along the shaft axis. The restriction of the degrees of freedom of the sliding sleeves 23, 24 and 25 is achieved by groove guides 41, 42, 43, which are nested within one another. The sliding sleeves 23, 24, and 25 are inserted into each other in such a way that an outer sleeve supports the inner sleeve. This results in a very compact design.

Accordingly, the outer sliding sleeve 23 is mounted in the instrument shaft 3. A transition fit between the sleeve 23 and the shaft 3 serves as a radial bearing. Rotation of the sleeve 23 is blocked by a key 41 fixed to the sleeve 23, which slides in a groove formed in the instrument shaft 3. The sliding sleeve 24 is mounted in the outer sliding sleeve 23. A transition fit between sleeve 24 and sleeve 25 serves as a radial bearing. Rotation of the sleeve 24 is blocked by the groove guide 42. The inner sliding sleeve 25 is mounted in the sliding sleeve 24. A transition fit between sleeve 25 and sleeve 24 serves as a radial bearing. Rotation of the sleeve 25 is blocked by the groove guide 43.

The coupling of the drive shafts to the sliding sleeves is carried out by means of a groove guide, the functioning of which is exemplified with reference to the internal hollow shaft 18 and 11 is explained, which shows an enlarged section. A helical groove 37 is provided at the distal end of the hollow shaft 18. A pin 38, which is fixed to the sliding sleeve 25, engages positively in the helical groove 37. Thus, rotation of the hollow shaft 18 leads to a displacement of the sleeve 25 along the shaft axis and thus also to an adjusting movement of the pulling and/or pushing means 26. The pulling and/or pushing means 26, 39 and 40, which transmit the drive movement to the instrument degrees of freedom or to an end effector at the distal end of the instrument shaft 3, are connected to the distal end of the sliding sleeves 23, 24 and 25.

One advantage of this solution is that the drive movements, especially the setting angle and angular velocity, can be adapted to the specific requirements of each instrument, since the pitch of the guide rail determines the transmission ratio and the operating range. This allows the drive unit to be used for the largest possible number of different instruments, increasing cost-effectiveness and user-friendliness.

Instead of the 10 , 11 In addition to the proximal arrangement shown, the transfer gear can alternatively be arranged at the distal end of the instrument, i.e. as close as possible to the instrument kinematics and the end effector. 12 shows an instrument 400 according to an embodiment of the present invention connection with a distal transfer gear in a perspective overall view (top in 12 ) or an enlarged partial section (below in 12 ).

The conversion gear is located at the distal end of the instrument 400 and thus close to the instrument kinematics 402 and the end effector 403. The actuation of the distal joint 402, which in the example shown is designed as a parallel kinematics, is carried out by pulling and/or pushing means in the form of coupling rods 408 and 409, which are rotatably connected to the segment that carries the end effector. The other ends of the coupling rods 408 and 409 are rotatably connected to the sliding sleeves 406 and 407, which are moved along the shaft axis to adjust the joint angle. The sliding sleeves 406 and 407 are connected to the hollow shafts 404 and 405, respectively, wherein the conversion of the rotary drive movement into the translatory feed movement of the sleeve is carried out with the 10 , 11 described link mechanism. Sufficient space remains in the center of the inner hollow shaft 405 to accommodate drive means, for example a Bowden cable or a rotary shaft with a flexible section in the area of the multiple joint for driving the end effector 403 and/or an additional instrument, in particular electrical supply lines, hoses, or the like.

In contrast to the cable pulls used in conventional instruments for minimally invasive robotic surgery, this design transmits the drive power from the drive unit to the instrument tip via hollow shafts coaxial with the instrument shaft. This can result in significantly higher load capacity and rigidity of the drive train compared to cable pulls or thin solid shafts, advantageously allowing higher drive forces to be transmitted. This design is therefore particularly recommended for instruments subject to higher process forces, such as staplers.

Sterile barrier between drive unit and instrument

Some components of the drive unit cannot withstand the environmental conditions during a sterilization process. Therefore, the instrument interface features a sterile sheath that covers the drive unit during operation. In addition to the sheath, which securely encloses the drive unit housing and is typically designed as a film tube, the instrument interface between the drive unit and the instrument is designed to enable the transmission of mechanical power and electrical signals while simultaneously preventing contamination of the surgical field by the unsterile drive unit.

13 shows an overview of the instrument interface 500 with various subcomponents that are used, for example, in the instrument arrangement of the 1 may be provided.

The instrument interface 500 comprises a sterile foil cover 501 which encloses the housing of the drive unit 2, a dimensionally stable flange or instrument carrier 5 which, for coupling the drive trains, for example, the 4 described conical intermediate elements 19, 20, 21, as well as an internal passage in the form of the guide tube 27. A closure ring 503 connects the guide tube 27 to the foil sleeve 501. In order to maintain the sterility of the guide tube 27 upon insertion into the drive unit 2, the guide tube 27 is initially closed at its proximal end with a blind plug 502, which covers part of the outer surface. The instrument interface 500 is designed as a complete assembly in which all individual parts are connected to form a single unit. This greatly simplifies handling. In the case of the device described with reference to 8 For the magnetic coupling explained above, a film is sufficient as a sterile barrier or instrument interface between the shaft sections.

The other 14 to 17 illustrate the sterile packaging of the drive unit and the connection of a surgical instrument to it. As a first step (see 14 ), the instrument carrier 5 is placed on the drive unit. At the same time, the sterile guide tube 27 is inserted into the hollow shaft, as are the intermediate pieces 19, 20, 21 of the shaft couplings, into the drive unit 2, and the foil cover is slipped over the drive unit 2. Then, the blind plug 502, which is unsterile after the sterile guide tube 27 has been pushed through the hollow shaft of the drive unit 2, is removed from the guide tube 27 by a non-sterile member of the surgical team and disposed of (see 15 ). Since the blind plug 502 also covers part of the outer surface of the guide tube 27, the section of the guide tube 27 that protrudes from the drive unit 2 remains sterile. Finally, the sterile sheath is closed by joining the end ring 503 to the guide tube 27 (see 16 ). 17 finally shows the docking of a surgical instrument 1 to the sterile packaged drive unit 2.

Guide additional drive trains and/or additional instruments through the instrument shaft to the distal end of the instrument

In addition to the simple mechanical design of the detachable instrument interface, the coaxial arrangement of all drive shafts offers the advantage that the center of the drive unit and instrument is free to accommodate additional drive devices, such as cables, Bowden cables, and/or rotary shafts, to actuate the end effector. For example, a Bowden cable can be used twice: the sleeve transmits a first actuation force, the core transmits a second. Electrical cables for monopolar or bipolar instruments, or suction and irrigation hoses, can also be routed through the center of the instrument shaft. Likewise, other additional instruments can also be routed through the robot, such as fiber optic cables for laser applications or flexible instruments for argon plasma coagulation, cryosurgery, or waterjet surgery, which are frequently used for tumor resection.

18 shows an instrument arrangement with a rigid or flexible additional instrument inserted or passed through.

For this purpose, the additional instrument 504 is advanced from the rear through the guide tube 27 through the drive unit 2 to the distal end of the instrument 1 after applying the sterile sheath 501 and is secured in this position. The additional instrument 504 can then be used like a conventional robot-guided instrument and moved within the surgical field with the degrees of freedom provided by the instrument 1. In addition to its suitability for rigid and flexible additional instruments, an advantage of this solution is that no additional installation space is required in the area of the detachable instrument interface to insert the additional instrument 504 into the instrument shaft.

19 shows part of an instrument of an instrument assembly according to a further embodiment of the present invention, which is particularly suitable for flexible additional instruments. Here, the additional instrument 507 is not inserted through the drive unit 2, but through a bent tube section 506, which is arranged on the instrument shaft 505 directly in front of the drive unit 2 or instrument interface. With this solution, the sterile sheath 501 can be designed more simply, since the additional instrument 507 is not guided through the drive unit from behind.

20 shows part of an instrument of an instrument arrangement according to a further embodiment of the present invention, in which the drive and shaft axes are orthogonal. Both rigid and flexible additional instruments can be inserted or passed through. The additional instrument 508 is advanced and fixed by a guide tube 115 from behind through the housing 104 to the distal end of the instrument shaft 103. The additional instrument 508 can then be used like a conventional robot-guided instrument and moved within the surgical field with the degrees of freedom provided by the instrument 100. Here, too, no installation space is required at the proximal end of the instrument shaft to insert the additional instrument 508.

The drive unit provides the mechanical drive power for all active degrees of freedom of the surgical instrument. It is located at the proximal end of the instrument and is designed as a standalone module suitable for driving various instruments. To prevent contamination of the surgical field, the drive unit is hermetically sealed with a sterile protective cover.

The detachable instrument interface is located between the drive unit and the surgical instrument. Its primary function is the mechanical connection of the surgical instrument to the drive unit. It establishes the power flow between the drive and instrument functional units and ensures precise and repeatable relative positioning and fixation of these units. To transfer the required mechanical power to the instrument, the detachable instrument interface also includes detachable couplings that establish the power flow between the individual drives in the drive unit and the drive trains in the instrument. To ensure the sterility of the surgical instrument under all circumstances, the detachable instrument interface also acts as a sterile barrier between the non-sterile drive unit and a sterile instrument.

Advantageously, the coupling of a surgical instrument to an instrument assembly according to an embodiment of the present invention is simple and does not require in-depth knowledge of the robot system. The separable instrument interface according to an embodiment advantageously allows The repeatable, reliable coupling of the instrument, including all power transmission elements, without visual inspection. The interface can preferably transmit one or more drive movements from a drive unit to a surgical instrument, while maintaining sterility on the instrument side. The drive unit and/or detachable instrument interface advantageously require a small installation space, minimizing the risk of collision, particularly in a system with multiple robots. To improve the performance of the robot-guided instrument from a control engineering perspective, the transmission of mechanical drive energy to the surgical instrument is designed to be as free from play and slippage as possible.

21A , 21B show a covering of a robot with a cover according to an embodiment of the present invention. The robot, whose robot hand is in 21A , 21B partially indicated, has a hollow shaft. A hose-like inner passage 27 of a sleeve 501, which has an outlet opening 507, is guided through this. The passed-through end of the inner passage 27 is initially covered, for example by clamping, with a blind plug 502, which has a closed end face and a tubular outer surface in order to protect the interior and a front-side peripheral area of the inner passage 27 from contamination during passage.

The blind plug 502 is passed through the hollow shaft and the outlet opening 507 ( 21A) and then removed. A sterile sealing ring 503A, 503B is attached to the peripheral area of the inner passage 27 and the edge of the outlet opening 507, again for example by clamping ( 21 B) This makes it easy to create a sterile enclosure for the robot with a hollow shaft or, equally, for the drive unit of an instrument assembly.

In the exemplary embodiment, the inner leadthrough 27 is at its end opposite the blind plug 502 or end ring 503 (bottom in 21A , 21B) rotatably mounted on the sleeve 501, for example as described above with reference to the intermediate elements of the instrument interface. The end ring is formed in two parts, with a part 503A of the end ring fastened to the peripheral region of the inner feedthrough being rotatably mounted on a part 503B of the end ring fastened to the outlet opening of the sleeve. In this way, the inner feedthrough 27 as a whole is rotatably mounted on the sleeve 501 and can, in particular, be rotated along with an additional instrument moved through the hollow shaft. In a modification (not shown), the inner feedthrough can also be formed integrally or in one piece with the sleeve and/or connected by means of a one-piece end ring, whereby any rotation of the hollow shaft can be compensated for, for example, by looseness in the inner feedthrough or sleeve.

List of reference symbols

1, 100, 101, 400

instrument

2, 102

drive unit

4

connecting flange

3, 103, 505

instrument shaft

5, 105, 501

(sterile) cover

6, 104

Housing

7, 8, 9

electric motor

11, 12, 14, 28, 29, 30

storage location

19, 20, 21, 206, 207, 208

Intermediate element

22

Implementation gear

23, 24, 25, 37, 38, 200, 201, 202, 406, 407

Sliding sleeve (sliding guide)

26, 39, 40

Pulling/pushing means

31-36, 200-205, 300-305

Spur gearing (coupling part)

27, 115

(sterile) guide tube

37

spiral groove

38

Pen

41, 42 ,43

Groove guide

10, 13, 15, 16, 17, 18, 106, 107, 108, 109, 110, 111, 404, 405, 406

drive shaft

402

Instrument kinematics

403

End effector

408, 409

coupling rod

100

instrument-side conversion gear

112, 113, 114

Cable pulleys

115

guide tube

116, 117, 118

Coupling intermediate segment

209, 210, 211

retaining ring

500

Instrument interface

501

(sterile) foil cover

502

Blind plugs

503

closing ring

504, 507, 508

Additional instrument

506

Pipe section

507

Exit opening

Claims (10)

Sheath with a tubular inner passage for passage through a hollow shaft of a robot or a drive unit (2; 102) for an instrument assembly that can be fastened, in particular detachably, to a robot of a surgical robot system, the drive unit (2; 102) comprising at least one rotary drive (7, 8, 9) with a drive shaft, in particular a hollow drive shaft (10, 13, 15; 106, 107, 108), with a coupling part (31, 32, 33; 200, 201, 202; 300, 301, 302) for coupling to a drive shaft of an instrument of the instrument assembly, and through an outlet opening (507) of the sheath, wherein the inner passage has a blind plug (502) and a sealing ring (503) for fastening to a peripheral region of the inner passage, which can be removed of the blind plug (502) is released. Method for enclosing a robot or a drive unit (2; 102) for an instrument arrangement by means of a cover according to Claim 1 , characterized in that the inner leadthrough provided with the blind plug (502) is passed through a hollow shaft and the outlet opening of the casing, is then removed and the end ring (503) is fastened to the peripheral region of the inner leadthrough which has become free by the removal of the blind plug (502). Instrument interface for an instrument arrangement for, in particular detachable, fastening to a robot of a surgical robot system, the instrument arrangement comprising: a drive unit (2; 102) with at least one rotary drive (7, 8, 9) with a drive shaft, in particular a hollow drive shaft (10, 13, 15; 106, 107, 108), with a coupling part (31, 32, 33; 200, 201, 202; 300, 301, 302) for coupling to a drive shaft of an instrument; and an instrument (1; 100; 400) with an instrument shaft (3) and at least one drive shaft, in particular a hollow drive shaft (16, 17, 18; 109, 110, 111; 404, 405, 406), with a coupling part (34, 35, 36; 203, 204, 205; 303, 304, 305) for coupling to a drive shaft of the drive unit (2; 102); wherein the instrument (1; 100; 400) is detachably connected to the drive unit (2; 102); wherein the instrument interface (5, 500) can be arranged between the drive unit (2; 102) and the instrument (1; 100; 400); wherein the instrument interface (5, 500) has a sheath (5, 501) for enclosing the drive unit (2; 102) of the instrument arrangement, said sheath (5, 501) having an internal passage (27) for an additional instrument introduced through the instrument and the drive unit of the instrument arrangement and/or a sheath (5, 501) according to Claim 1 is. Instrument interface according to Claim 3 , characterized by at least one rotatable, in particular conical, intermediate element (19, 20, 21; 206, 207, 208) for frictional or positive coupling with the coupling part of a drive shaft of the drive unit and/or the instrument. Instrument arrangement for, in particular detachable, attachment to a robot of a surgical robot system, comprising: a drive unit (2; 102) with at least one rotary drive (7, 8, 9) with a drive shaft, in particular a hollow drive shaft (10, 13, 15; 106, 107, 108), with a coupling part (31, 32, 33; 200, 201, 202; 300, 301, 302) for coupling to a drive shaft (16, 17, 18; 109, 110, 111; 404, 405, 406) of an instrument (1; 100; 400); the instrument (1; 100; 400) with an instrument shaft (3) and the drive shaft of the instrument (1; 100; 400), in particular a hollow drive shaft (16, 17, 18; 109, 110, 111; 404, 405, 406), with a coupling part (34, 35, 36; 203, 204, 205; 303, 304, 305) for coupling to the drive shaft of the drive unit, which coupling part is detachably connected to the drive unit (2; 102); and an instrument interface (5, 500) according to one of the Claims 3 until 4 which is arranged between the drive unit (2; 102) and the instrument (1; 100; 400). Instrument arrangement according to Claim 5 , characterized in that the instrument arrangement has an additional instrument (504) and/or a drive means for actuating an end effector, which is inserted, in particular detachably, through the instrument of the instrument arrangement; and/or that at least one drive shaft (10, 13, 15; 106, 107, 108) of the drive unit and a drive shaft (16, 17, 18; 109, 110, 111; 404, 405, 406) of the instrument are arranged coaxially, in particular in alignment; and/or that a coupling part (300, 301, 302) of a drive shaft of the drive unit and a coupling part (303, 304, 305) of a drive shaft of the instrument are magnetically coupled to one another. Instrument arrangement according to one of the Claims 5 until 6 , characterized in that the drive unit has at least one inner drive shaft, in particular a hollow drive shaft, which is arranged, in particular mounted, concentrically in an outer hollow drive shaft; and/or that at least one rotary drive is arranged coaxially, in particular aligned or offset parallel, or at an angle, in particular at a right angle, to its drive shaft; and/or that the coupling part of the drive unit is arranged axially displaceably, in particular prestressed, on the drive shaft. Instrument arrangement according to one of the Claims 5 until 7 , characterized in that the instrument has at least one inner drive shaft, in particular a hollow drive shaft, which is arranged, in particular mounted, concentrically in an outer hollow drive shaft; and/or that the drive shaft of the instrument is arranged coaxially, in particular aligned or offset parallel, or at an angle, in particular at a right angle, to the instrument shaft; and/or that the instrument has a conversion gear for converting a rotation of a drive shaft into a translation of a pulling and/or pushing means. Instrument arrangement according to Claim 8 , characterized in that the conversion gear has a slotted guide (23, 24, 25, 37, 38) and/or is arranged in a half of the instrument shaft facing towards or away from the drive unit. Surgical robot system comprising: a robot; and an instrument arrangement according to one of the Claims 5 until 9 .