DE102021119434A1 - Medical instrument and method of manufacturing a medical instrument - Google Patents

Abstract

In order to improve a medical instrument with a first instrument part and at least one second instrument part, the instrument comprising at least one plain bearing for movably mounting the first instrument part and the at least one second instrument part on one another, the at least one plain bearing comprising two mutually interacting bearing surfaces, that a course of the medical instrument is preserved longer, it is proposed that at least one of the two interacting bearing surfaces of the at least one plain bearing is work-hardened and smoothed by burnishing. Furthermore, an improved method for producing a medical instrument is proposed.

Description

The present invention relates to a medical instrument with a first instrument part and at least one second instrument part, the instrument comprising at least one plain bearing for movably mounting the first instrument part and the at least one second instrument part on one another, the at least one plain bearing comprising two mutually interacting bearing surfaces.

Furthermore, the present invention relates to a method for producing a medical instrument with a first instrument part and at least one second instrument part, at least one plain bearing being formed on the instrument for movably mounting the first instrument part and the at least one second instrument part on one another, the at least one plain bearing having two interacting bearing surfaces is formed.

Medical instruments of the type described above are known in a wide variety of embodiments. For example, they include two rigid branches that are movably coupled to one another in the area of a so-called instrument connection. In the area of the end, which includes at least one plain bearing, two cooperating bearing surfaces of the plain bearing are in contact with one another.

If the instrument is manufactured, the instrument parts are in particular movably connected to one another in such a way that the bearing surfaces rest against one another, but allow a relative movement of the instrument parts. This means that a user has to apply a certain force in order to move the two instrument parts relative to one another. Without such a force, the instrument parts maintain their relative position, regardless of an opening angle of the instrument. Such an adjustment of the instrument is also referred to as a so-called "sucking gait".

A problem with such instruments is in particular that a movement of the instrument parts relative to one another leads to changes in the bearing surfaces. In particular, these changes can have the undesired consequence that the instrument parts no longer maintain their relative position because they are no longer in contact with one another, as a result of which the “sucking action” described is not permanently maintained.

It is therefore an object of the present invention to improve a medical instrument and a method for producing a medical instrument of the type described at the outset in such a way that the movement of the medical instrument is maintained for longer.

In the case of a medical instrument of the type described above, this object is achieved according to the invention in that at least one of the two interacting bearing surfaces of the at least one plain bearing is work-hardened and smoothed by burnishing.

The proposed further development of a known medical instrument has the particular advantage that the bearing surface machined by roller burnishing cannot change or can only change insignificantly when the instrument is used. Thus, an undefined deformation of the bearing surface can no longer occur, for example due to a mutual reduction in the roughness of the bearing surfaces when they slide against one another as a result of a movement of the instrument parts relative to one another. The respective instrument part is hardened and smoothed in the region of the bearing surface by the smooth rolling of one or both interacting bearing surfaces of the at least one plain bearing. As a result, relative movements of the instrument parts only lead to insignificant or no longer significant changes in the bearing surfaces. Instruments with such instrument parts can be coupled to one another as with conventional instruments. In particular, the instrument can be adjusted in such a way that the “sucking gait” described above is achieved. The proposed processing of the bearing surfaces by smooth rolling, which can be easily verified by micrographs of grindings of the bearing surfaces, leads to fewer changes in the bearing surfaces, as described, and thus to a significantly longer service life of the instruments while retaining the original setting of the respective plain bearing. Consequently, the set gear is retained longer. An improvement already results if only one of the two bearing surfaces forming the at least one plain bearing is machined by burnishing. Both interacting bearing surfaces are preferably work-hardened and smoothed by smooth rolling, as a result of which the service life of the instrument can be increased even further.

It is favorable if the first instrument part and the at least one second instrument part are mounted on one another such that they can pivot about a pivot axis. In this way, in particular medical instruments in the form of needle holders, clamps or the like can be formed in a simple manner.

The two interacting bearing surfaces preferably run transversely, in particular perpendicularly, to the pivot axis. In particular, they can be concentric to the pivot axis. In this way, the machining of the instrument parts can be minimized, namely the burnishing can be limited to the area of the bearing surfaces.

It is advantageous if a reflectivity of the at least one work-hardened bearing surface is greater than a reflectivity of a bearing surface that is not work-hardened or of a surface region of the instrument that is not work-hardened. In this way, a user can see directly whether he is using an instrument with only one work-hardened bearing surface or with two work-hardened bearing surfaces. The higher the reflectivity, the lower the roughness of the surface of the instrument parts, ie in particular also in the area of the bearing surfaces.

The instrument preferably comprises only two instrument parts, namely a first instrument part and a second instrument part. For example, medical instruments can be designed with two branches that can be pivoted relative to one another, for example needle holders or clamps.

Furthermore, it can be advantageous if the instrument comprises three instrument parts, namely a first instrument part and two second instrument parts. Such an instrument can therefore in particular comprise three branches that can be pivoted relative to one another. For example, instruments with two different functions can be implemented. Such instruments have at least two sliding bearings, each with two interacting bearing surfaces.

Preferably, the two cooperating bearing surfaces each define a bearing surface plane. In other words, the interacting bearing surfaces are preferably flat. In this way, the greatest possible contact between the storage areas can be achieved.

In order in particular to achieve a long service life and a permanently constant "sucking action", it is favorable if a first roughness of the at least one work-hardened bearing surface is smaller than a second roughness of a bearing surface that has not work-hardened or of a surface area of the instrument that has not worked-hardened. The lower the roughness of the bearing surface, the less the bearing surface can change due to a relative movement of the instrument parts. In particular, a reduction in the roughness of the bearing surfaces as a result of a relative movement of the instrument parts to one another can be achieved by a defined reduction in the roughness during manufacture of the instrument parts by burnishing the bearing surfaces.

Conveniently, the first roughness is at most about 20% of the second roughness. In particular, it is at most about 10%. The lower the roughness after roller burnishing, the less the bearing surfaces can change, so that an instrument with a long service life and a permanently constant action, for example a “sucking action”, can be formed.

According to a further preferred embodiment it can be provided that the first instrument part comprises a first bearing section, that the at least one second instrument part comprises a second bearing section and that the interacting bearing surfaces are formed on the first bearing section and on the second bearing section. Such a configuration makes it possible, in particular, to design the sliding bearing on the instrument in a defined manner. For example, by designing the bearing sections, it can be specified whether, for example, an instrument is to be designed with a so-called laid-on closure or a so-called push-through closure.

It is favorable if the first bearing section has at least one first bearing section side, if the at least one second bearing section has at least one second bearing section side, if the at least one first bearing section side and the at least one second bearing section side face each other and that on the at least one first bearing section side and one of the two interacting bearing surfaces of the at least one plain bearing is arranged or formed on the at least one second bearing section side. This configuration makes it possible, in particular, to design the instrument with its bearing sections in a defined manner. In particular, the bearing surfaces can be formed directly on the bearing section sides, ie the bearing surface planes and the planes defined by the bearing section sides can coincide.

It is advantageous if the at least one first bearing section side comprises a first bearing element, if the at least one second bearing section side comprises a second bearing element, if the first bearing element comprises a first bearing element side surface, if the second bearing element comprises a second bearing element side surface and if the first bearing element side surface and the second bearing element side surface each form one of the two cooperating bearing surfaces of the at least one plain bearing. This configuration has the particular advantage that the size of the bearing surfaces can be specified by the shape and size of the bearing elements. In particular, it can be avoided that edges of the bearing sections deform, in particular damage, the mutually facing bearing section sides of the bearing sections. In particular, the bearing elements make it possible to offset the bearing surfaces relative to the sides of the bearing section.

It is favorable if the first bearing section side defines a first bearing section side surface, if the second bearing section side defines a second bearing section side surface and if the first bearing element and/or the second bearing element are designed in the form of a bearing projection protruding from the first bearing section side surface. Providing one or two such bearing projections makes it possible in particular to limit the areas in which the instrument parts bear against one another, in particular during a relative movement, to the bearing surfaces. A risk of damage to the bearing surfaces, in particular from edges of the instrument sections, can thus be significantly reduced or even completely ruled out.

It is advantageous if the first bearing section side defines a first bearing section side surface, if the second bearing section side defines a second bearing section side surface and if the first bearing element is designed in the form of a bearing projection protruding from the first bearing section side surface and if the second bearing element is designed in the form of a bearing recess corresponding to the bearing projection is. Such a configuration makes it possible, in particular, to accommodate the bearing projection in the bearing recess and thus in particular to limit a relative movement in a direction parallel to the bearing surfaces.

It is favorable if the bearing projection has a bearing height in relation to the first bearing section side surface and the bearing recess has a bearing depth in relation to the second bearing section side surface and if the bearing height is greater than the bearing depth. In particular, the storage height can be at least 10% greater than the storage depth. Such a configuration can in particular ensure that the bearing section sides of the bearing sections cannot come into contact with one another. In particular, damage to the bearing surfaces caused by edges of the bearing sections can be avoided in this way.

It is advantageous if the bearing surface on the bearing projection is smaller than on the bearing recess and if the bearing surfaces are dimensioned such that the bearing projection in the bearing recess can be rotated about the pivot axis by at least one opening angle of the instrument when the bearing surfaces are in contact. Such a design can in particular ensure that the instrument parts can be pivoted relative to one another in the desired manner. It is also possible, for example, to limit the opening in a simple manner, for example by appropriately shaping the bearing recess and the bearing projection in such a way that they can only be pivoted relative to one another over a predetermined angular range. Consequently, interacting stop surfaces can be formed on the bearing projection and the bearing recess.

The first bearing section and the second bearing section preferably work together to form an instrument closure. In particular, this makes it possible to design the instrument in a defined manner and to couple the instrument parts to one another in a movable manner in a defined manner.

It is advantageous if one of the two bearing sections has a bearing section opening and if the other of the two bearing sections passes through the bearing section opening to form the instrument connection in the form of a push-through connection. Such a push-through connection has the advantage that the bearing section with the bearing section opening can guide the other bearing section on both sides. In this way, in particular, improved guidance of the two instrument parts that are movably coupled to one another can be achieved relative to one another.

Furthermore, it is advantageous if the first and the second bearing section are designed without any openings and rest against one another to form the instrument connection in the form of an overlaid connection. Such a configuration makes it possible, in particular, to use two completely identical instrument parts to form an instrument. This minimizes a design effort and also a manufacturing effort.

At least one of the two interacting bearing surfaces is preferably of rotationally symmetrical design. In particular, it is concentric to the pivot axis. Of course, both bearing surfaces can also be designed in a corresponding manner, so that they lie flat against one another, in particular with bearing surfaces that are identical in size and shaped and/or machined.

In order to minimize deformation of the at least two bearing surfaces due to a relative movement of the instrument parts or, if possible, to rule it out entirely, it is favorable if the two interacting bearing surfaces are geometrically similar. In particular, they can be of the same size. In particular, peripheral edges of Bearing surfaces, if they are formed by bearing section side surfaces of bearing projections, be rounded in order to avoid unwanted mutual deformation of the bearing surfaces.

The object stated at the outset is also achieved according to the invention in a method of the type described at the outset in that at least one of the two interacting bearing surfaces of the at least one plain bearing is work-hardened and smoothed by smooth rolling.

As already described above, the proposed further development has the particular advantage that the bearing surfaces cannot, or only insignificantly, change further when the instrument is used. This then leads to less deformation of the bearing surfaces and thus to maintaining the setting, ie a course, of the instrument, and therefore of the instrument parts relative to one another. In particular, a "sucking gait" as described at the beginning can be maintained permanently without having to adjust the instrument.

It is favorable if at least one of the two bearing surfaces is burnished until the reflectivity of the bearing surface is at least 50% greater than before burnishing. This makes it easy to check quality during the manufacture of the instrument. It is therefore only necessary to measure and compare the reflectivity before roller burnishing and after roller burnishing. If the specified values are not reached, the respective bearing surface must be further processed.

Furthermore, it is advantageous if at least one of the two bearing surfaces is smooth-rolled until the roughness of the bearing surface is smaller than before the smooth-rolling. In particular, smooth rolling can be carried out until the roughness is at most about 20%. It is even better if the roughness after burnishing is at most about 10% compared to the original roughness. The lower the roughness after roller burnishing, the less the bearing surfaces that work together can further deform each other when the instrument is used. The development described makes it possible to increase the service life of medical instruments and to maintain the originally set gear for a long time.

The instrument part on which the bearing surface is burnished is preferably heated to a temperature of at least about 100° C. during burnishing. In this way, optimal consolidation and smoothing of the bearing surfaces can be achieved.

In order to be able to process the bearing surfaces quickly and in the desired manner, it is advantageous if the bearing surface is subjected to a pressure of at least 10 kPa during burnishing.

According to a further preferred embodiment, it can be provided that the bearing surface is machined with a rolling tool and that the rolling tool is rotated about the pivot axis of the instrument during smooth rolling. In this way it can be achieved in particular that the bearing surface is smoothed all the way around the pivot axis. In particular, a microstructure can be specified in the direction of rotation of the rolling tool. This is then retained on the storage area.

Favorably, during burnishing, the rolling tool is only rotated in one direction of rotation relative to the pivot axis. In particular, a microstructure of the respective bearing surface can be formed in the direction of rotation.

It is advantageous if a rolling tool with at least two, in particular three, rolling elements is used for burnishing and if the at least two rolling elements are designed cylindrically or in the shape of a truncated cone. Different pressure distributions can be specified when working on the bearing surfaces through the number and shape of the rolling elements. In this way, the bearing surfaces can be strengthened and smoothed in the desired manner.

During burnishing, the at least two roller elements are preferably each rotated about a roller axis which runs in a plane perpendicular to the pivot axis. In particular, the rolling tool can be rotated in a simple manner about the pivot axis of the instrument in order to form a bearing surface with a defined rotational structure. Such an alignment of the roll axes is possible with both cylindrical and truncated cone-shaped rolling elements.

According to a further preferred embodiment, it can be provided that the first instrument part is formed with a first bearing section, that the at least one second instrument part is formed with a second bearing section and that the interacting bearing surfaces are formed on the first bearing section and on the second bearing section. In this way, the instrument parts can be processed in a defined manner, for example to form push-through closures or laid-up closures.

It is favorable if the first bearing section has at least one first bearing section side, if the at least one second bearing section has at least one second bearing section side if the at least one first bearing section side and the at least one second bearing section side face each other and one of the two interacting bearing surfaces of the at least one plain bearing is arranged or formed on the at least one first bearing section side and on the at least one second bearing section side. In particular, this further development enables the bearing sections to be designed in the desired manner in order to form instruments with different instrument connections.

Furthermore, it can be advantageous if a first bearing element is formed on the at least one first bearing section side, if a second bearing element is formed on the at least one second bearing section side, and if a first bearing element side surface of the first bearing element and a second bearing element side surface of the second bearing element interact as the two Bearing surfaces of the at least one plain bearing are formed. The bearing elements can either both be designed as a bearing projection or one as a bearing projection and the other as a corresponding bearing recess. As already described above, contact between the instrument sections and the interacting bearing surfaces can be reduced in this way.

The bearing sections can be formed in a simple manner if the first bearing element and/or the second bearing element are formed by machining. In particular, they can be formed by milling. The bearing elements can thus be formed in a first step by machining and then the bearing surfaces on the respective bearing elements can be work-hardened and smoothed by burnishing.

Furthermore, the use of one of the methods described above for producing one of the medical instruments described above is proposed.

1. 1. Medizinisches Instrument (10) mit einem ersten Instrumententeil (12) und mindestens einem zweiten Instrumententeil (14), wobei das Instrument (10) mindestens ein Gleitlager (46) umfasst zum beweglichen Lagern des ersten Instrumententeils (12) und des mindestens einen zweiten Instrumententeils (14) aneinander, wobei das mindestens eine Gleitlager (46) zwei miteinander zusammenwirkende Lagerflächen (52, 54) umfasst, dadurch gekennzeichnet, dass mindestens eine der zwei zusammenwirkenden Lagerflächen (52, 54) des mindestens einen Gleitlagers (46) durch Glattwalzen kaltverfestigt und geglättet ist.
2. 2. Medizinisches Instrument nach Satz 1, dadurch gekennzeichnet, dass das erste Instrumententeil (12) und das mindestens eine zweite Instrumententeil (14) um eine Schwenkachse (28) verschwenkbar aneinander gelagert sind.
3. 3. Medizinisches Instrument nach Satz 2, dadurch gekennzeichnet, dass die zwei zusammenwirkenden Lagerflächen (52, 54) quer, insbesondere senkrecht, zur Schwenkachse (28) verlaufen.
4. 4. Medizinisches Instrument nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass eine Reflektivität der mindestens einen kaltverfestigten Lagerfläche (52, 54) größer ist als Reflektivität einer nicht kaltverfestigten Lagerfläche (52, 54) oder eines nicht kaltverfestigten Oberflächenbereichs des Instruments (10).
5. 5. Medizinisches Instrument nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass das Instrument (10) nur zwei Instrumententeile (12, 14) umfasst, nämlich einen ersten Instrumententeil (12) und einen zweiten Instrumententeil (14).
6. 6. Medizinisches Instrument nach einem der Sätze 1 bis 4, dadurch gekennzeichnet, dass das Instrument (10) drei Instrumententeile (12, 14) umfasst, nämlich einen ersten Instrumententeil (12) und zwei zweite Instrumententeile (14).
7. 7. Medizinisches Instrument nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass die zwei zusammenwirkenden Lagerflächen (52, 54) jeweils eine Lagerflächenebene (76) definieren.
8. 8. Medizinisches Instrument nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass eine erste Rauheit der mindestens einen kaltverfestigten Lagerfläche (52, 54) kleiner ist als eine zweite Rauheit einer nicht kaltverfestigten Lagerfläche (52, 54) oder eines nicht kaltverfestigten Oberflächenbereichs des Instruments (10).
9. 9. Medizinisches Instrument nach Satz 8, dadurch gekennzeichnet, dass die erste Rauheit höchstens etwa 20% der zweiten Rauheit beträgt, insbesondere höchstens etwa 10%.
10. 10. Medizinisches Instrument nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass der erste Instrumententeil (12) einen ersten Lagerabschnitt (64) umfasst, dass der mindestens eine zweite Instrumententeil (14) einen zweiten Lagerabschnitt (66) umfasst und dass die zusammenwirkenden Lagerflächen (52, 54) am ersten Lagerabschnitt (64) und am zweiten Lagerabschnitt (66) ausgebildet sind.
11. 11. Medizinisches Instrument nach Satz 10, dadurch gekennzeichnet, dass der erste Lagerabschnitt (64) mindestens eine erste Lagerabschnittseite (68) aufweist, dass der mindestens eine zweite Lagerabschnitt (66) mindestens eine zweite Lagerabschnittseite (70) aufweist, dass die mindestens eine erste Lagerabschnittseite (68) und die mindestens eine zweite Lagerabschnittseite (70) aufeinander zu weisen und dass an der mindestens einen ersten Lagerabschnittseite (68) und an der mindestens einen zweiten Lagerabschnittseite (70) jeweils eine der zwei zusammenwirkenden Lagerflächen (52, 54) des mindestens einen Gleitlagers (46) angeordnet oder ausgebildet ist.
12. 12. Medizinisches Instrument nach Satz 11, dadurch gekennzeichnet, dass die mindestens eine erste Lagerabschnittseite (68) ein erstes Lagerelement (78) umfasst, dass die mindestens eine zweite Lagerabschnittseite (70) ein zweites Lagerelement (90) umfasst, dass das erste Lagerelement (78) eine erste Lagerelementseitenfläche (82) umfasst, dass das zweite Lagerelement (90) eine zweite Lagerelementseitenfläche (92) umfasst und dass die erste Lagerelementseitenfläche (82) und die zweite Lagerelementseitenfläche (90) jeweils eine der zwei zusammenwirkenden Lagerflächen (52, 54) des mindestens einen Gleitlagers (46) bilden.
13. 13. Medizinisches Instrument nach Satz 12, dadurch gekennzeichnet, dass die erste Lagerabschnittseite (68) eine erste Lagerabschnittseitenfläche (72) definiert, dass die zweite Lagerabschnittseite (70) eine zweite Lagerabschnittseitenfläche (74) definiert und dass das erste Lagerelement (78) und/oder das zweite Lagerelement (90) in Form eines von der jeweiligen Lagerabschnittseitenfläche (72, 74) abstehenden Lagervorsprungs (80) ausgebildet sind.
14. 14. Medizinisches Instrument nach Satz 12, dadurch gekennzeichnet, dass die erste Lagerabschnittseite (68) eine erste Lagerabschnittseitenfläche (72) definiert, dass die zweite Lagerabschnittseite (70) eine zweite Lagerabschnittseitenfläche (74) definiert und dass das erste Lagerelement (78) in Form eines von der ersten Lagerabschnittseitenfläche (72) abstehenden Lagervorsprungs (80) ausgebildet ist und dass das zweite Lagerelement (90) in Form einer zum Lagervorsprung (80) korrespondierenden Lagerausnehmung (94) ausgebildet ist.
15. 15. Medizinisches Instrument nach Satz 14, dadurch gekennzeichnet, dass der Lagervorsprung (80) eine Lagerhöhe (84) bezogen auf die erste Lagerabschnittseitenfläche (72) und die Lagerausnehmung (94) eine Lagertiefe (96) bezogen auf die zweite Lagerabschnittseitenfläche (74) aufweisen und dass die Lagerhöhe (84) größer ist als die Lagertiefe (96), insbesondere mindestens 10% größer.
16. 16. Medizinisches Instrument nach Satz 14 oder 15, dadurch gekennzeichnet, dass die Lagerfläche (52, 54) am Lagervorsprung (80) kleiner ist als an der Lagerausnehmung (94) und dass die Lagerflächen (52, 54) so bemessen sind, dass der Lagervorsprung (80) in der Lagerausnehmung (94) um die Schwenkachse (28) bei aneinander anliegenden Lagerflächen (52, 54) um mindestens einen Öffnungswinkel (98) des Instruments (10) verdrehbar ist.
17. 17. Medizinisches Instrument nach einem der Sätze 10 bis 16, dadurch gekennzeichnet, dass der erste Lagerabschnitt (64) und der zweite Lagerabschnitt (66) zusammenwirken zur Ausbildung eines Instrumentenschlusses (26).
18. 18. Medizinisches Instrument nach Satz 17, dadurch gekennzeichnet, dass der eine der zwei Lagerabschnitte (66, 68) eine Lagerabschnittdurchbrechung (100) aufweist und dass der andere der zwei Lagerabschnitte (66, 68) die Lagerabschnittdurchbrechung (100) durchsetzt zur Ausbildung des Instrumentenschlusses (26) in Form eines Durchsteckschlusses (48).
19. 19. Medizinisches Instrument nach Satz 17, dadurch gekennzeichnet, dass der erste und der zweite Lagerabschnitt (66, 68) durchbrechungsfrei ausgebildet sind und aneinander anliegen zur Ausbildung des Instrumentenschlusses (26) in Form eines aufgelegten Schlusses (50).
20. 20. Medizinisches Instrument nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass mindestens eine der zwei zusammenwirkenden Lagerflächen (52, 54) rotationssymmetrisch ausgebildet ist, insbesondere konzentrisch zur Schwenkachse (28).
21. 21. Medizinisches Instrument nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass die zwei zusammenwirkenden Lagerflächen geometrisch (52, 54) ähnlich sind, insbesondere gleich groß.
22. 22. Verfahren zum Herstellen eines medizinisches Instruments mit einem ersten Instrumententeil (12) und mindestens einem zweiten Instrumententeil (14), wobei am Instrument (10) mindestens ein Gleitlager (46) ausgebildet wird zum beweglichen Lagern des ersten Instrumententeils (12) und des mindestens einen zweiten Instrumententeils (14) aneinander, wobei das mindestens eine Gleitlager (46) mit zwei miteinander zusammenwirkenden Lagerflächen (52, 54) ausgebildet wird, dadurch gekennzeichnet, dass mindestens eine der zwei zusammenwirkenden Lagerflächen (52, 54) des mindestens einen Gleitlagers (46) durch Glattwalzen kaltverfestigt und geglättet wird.
23. 23. Verfahren nach Satz 22, dadurch gekennzeichnet, dass mindestens eine der zwei Lagerflächen (52, 54) so lange glattgewalzt wird, bis eine Reflektivität der Lagerfläche (52, 54) mindestens 50% größer ist als vor dem Glattwalzen.
24. 24. Verfahren nach Satz 22 oder 23, dadurch gekennzeichnet, dass mindestens eine der zwei Lagerflächen (52, 54) so lange glattgewalzt wird, bis eine Rauheit der Lagerfläche (52, 54) kleiner ist als vor dem Glattwalzen, insbesondere höchstes noch etwa 20% beträgt, weitere insbesondere noch höchstens etwa 10%.
25. 25. Verfahren nach einem der Sätze 22 bis 24, dadurch gekennzeichnet, dass das Instrumententeil (12, 14), an dem die Lagerfläche (52, 54) glattgewalzt wird, beim Glattwalzen auf eine Temperatur von mindestens etwa 100°C erwärmt wird.
26. 26. Verfahren nach einem der Sätze 22 bis 25, dadurch gekennzeichnet, dass die Lagerfläche (52, 54) beim Glattwalzen mit einem Druck von mindestens 10 kPa beaufschlagt wird.
27. 27. Verfahren nach einem der Sätze 22 bis 26, dadurch gekennzeichnet, dass die Lagerfläche (52, 54) mit einem Walzwerkzeug (104) bearbeitet wird und dass das Walzwerkzeug (104) beim Glattwalzen um die Schwenkachse (28) des Instruments (10) rotiert wird.
28. 28. Verfahren nach Satz 27, dadurch gekennzeichnet, dass das Walzwerkzeug (104) beim Glattwalzen nur in einer Rotationsrichtung bezogen auf die Schwenkachse (28) rotiert wird.
29. 29. Verfahren nach Satz 27 oder 28, dadurch gekennzeichnet, dass ein Walzwerkzeug (104) mit mindestens zwei, insbesondere drei, Walzelementen (110) zum Glattwalzen eingesetzt wird und dass die mindestens zwei Walzelemente (110) zylindrisch oder kegelstumpfförmig ausgebildet sind.
30. 30. Verfahren nach Satz 29, dadurch gekennzeichnet, dass die mindestens zwei Walzelemente (110) beim Glattwalzen jeweils um eine Walzenachse (112) verdreht werden, welche in einer Ebene (114) senkrecht zur Schwenkachse (28) verläuft.
31. 31. Verfahren nach einem der Sätze 22 bis 30, dadurch gekennzeichnet, dass der erste Instrumententeil (12) mit einem ersten Lagerabschnitt (64) ausgebildet wird, dass der mindestens eine zweite Instrumententeil (14) mit einem zweiten Lagerabschnitt (66) ausgebildet wird und dass die zusammenwirkenden Lagerflächen (52, 54) am ersten Lagerabschnitt (64) und am zweiten Lagerabschnitt (66) ausgebildet werden.
32. 32. Verfahren nach Satz 31, dadurch gekennzeichnet, dass der erste Lagerabschnitt (64) mindestens eine erste Lagerabschnittseite (68) aufweist, dass der mindestens eine zweite Lagerabschnitt (66) mindestens eine zweite Lagerabschnittseite (70) aufweist, dass die mindestens eine erste Lagerabschnittseite (68) und die mindestens eine zweite Lagerabschnittseite (70) aufeinander zu weisen und an der mindestens einen ersten Lagerabschnittseite (68) und an der mindestens einen zweiten Lagerabschnittseite (70) jeweils eine der zwei zusammenwirkenden Lagerflächen (52, 54) des mindestens einen Gleitlagers (46) angeordnet oder ausgebildet werden.
33. 33. Verfahren nach Satz 32, dadurch gekennzeichnet, dass an der mindestens einen ersten Lagerabschnittseite (68) ein erstes Lagerelement (78) ausgebildet wird, dass an der mindestens einen zweiten Lagerabschnittseite (70) ein zweites Lagerelement (90) ausgebildet wird und dass eine erste Lagerelementseitenfläche (82) des ersten Lagerelements (78) und eine zweite Lagerelementseitenfläche (92) des zweiten Lagerelements (90) als die zwei zusammenwirkenden Lagerflächen (52, 54) des mindestens einen Gleitlagers (46) ausgebildet werden.
34. 34. Verfahren nach Satz 33, dadurch gekennzeichnet, dass das erste Lagerelement (78) und/oder das zweite Lagerelement (90) durch spanende Bearbeitung, insbesondere durch Fräsen, ausgebildet werden.
35. 35. Verwendung eines Verfahrens nach einem der Sätze 22 bis 34 zur Herstellung eines medizinischen Instruments (10) nach einem der Sätze 1 bis 21.

The above description thus includes in particular the embodiments of medical instruments and methods for producing medical instruments defined below in the form of numbered sentences:

1. 1. Medical instrument (10) with a first instrument part (12) and at least one second instrument part (14), wherein the instrument (10) comprises at least one plain bearing (46) for movably supporting the first instrument part (12) and the at least one second instrument part (14) to one another, the at least one plain bearing (46) comprising two mutually interacting bearing surfaces (52, 54), characterized in that at least one of the two interacting bearing surfaces (52, 54) of the at least one plain bearing (46) is work-hardened by burnishing and is smoothed.
2. 2. Medical instrument according to clause 1, characterized in that the first instrument part (12) and the at least one second instrument part (14) are mounted on one another such that they can pivot about a pivot axis (28).
3. 3. Medical instrument according to sentence 2, characterized in that the two interacting bearing surfaces (52, 54) run transversely, in particular perpendicularly, to the pivot axis (28).
4. 4. Medical instrument according to one of the preceding sentences, characterized in that a reflectivity of the at least one work-hardened bearing surface (52, 54) is greater than the reflectivity of a non-work-hardened bearing surface (52, 54) or a non-work-hardened surface area of the instrument (10).
5. 5. Medical instrument according to one of the preceding sentences, characterized in that the instrument (10) comprises only two instrument parts (12, 14), namely a first instrument part (12) and a second instrument part (14).
6. 6. Medical instrument according to one of sentences 1 to 4, characterized in that the instrument (10) comprises three instrument parts (12, 14), namely a first instrument part (12) and two second instrument parts (14).
7. 7. Medical instrument according to one of the preceding sentences, characterized in that the two interacting bearing surfaces (52, 54) each define a bearing surface plane (76).
8. 8. Medical instrument according to one of the preceding sentences, characterized in that a first roughness of the at least one work-hardened bearing surface (52, 54) is smaller than a second roughness of a non-work-hardened bearing surface (52, 54) or a non-work-hardened surface region of the instrument ( 10).
9. 9. Medical instrument according to sentence 8, characterized in that the first roughness is at most about 20% of the second roughness, in particular at most about 10%.
10. 10. Medical instrument according to one of the preceding sentences, characterized in that the first instrument part (12) comprises a first bearing section (64) that the at least one second instrument part (14) comprises a second bearing section (66) and that the cooperating bearing surfaces (52, 54) are formed on the first bearing section (64) and on the second bearing section (66).
11. 11. Medical instrument according to sentence 10, characterized in that the first bearing section (64) has at least one first bearing section side (68), that the at least one second bearing section (66) has at least one second bearing section side (70), that the at least one first Bearing section side (68) and the at least one second bearing section side (70) point towards one another and that on the at least one first bearing section side (68) and on the at least one second bearing section side (70) one of the two interacting bearing surfaces (52, 54) of the at least a plain bearing (46) is arranged or formed.
12. 12. Medical instrument according to sentence 11, characterized in that the at least one first bearing section side (68) comprises a first bearing element (78), that the at least one second bearing section side (70) comprises a second bearing element (90), that the first bearing element ( 78) comprises a first bearing element side surface (82), that the second bearing element (90) comprises a second bearing element side surface (92) and that the first bearing element side surface (82) and the second bearing element side surface (90) each have one of the two cooperating bearing surfaces (52, 54) of the at least one plain bearing (46).
13. 13. Medical instrument according to sentence 12, characterized in that the first bearing section side (68) defines a first bearing section side surface (72), that the second bearing section side (70) defines a second bearing section side surface (74) and that the first bearing element (78) and/or or the second bearing element (90) is designed in the form of a bearing projection (80) protruding from the respective bearing section side face (72, 74).
14. 14. Medical instrument according to sentence 12, characterized in that the first bearing section side (68) defines a first bearing section side surface (72), that the second bearing section side (70) defines a second bearing section side surface (74) and that the first bearing element (78) in the form a bearing projection (80) projecting from the first bearing section side surface (72) and that the second bearing element (90) is constructed in the form of a bearing recess (94) corresponding to the bearing projection (80).
15. 15. Medical instrument according to sentence 14, characterized in that the bearing projection (80) has a bearing height (84) in relation to the first bearing section side surface (72) and the bearing recess (94) has a bearing depth (96) in relation to the second bearing section side surface (74). and that the bearing height (84) is greater than the bearing depth (96), in particular at least 10% greater.
16. 16. Medical instrument according to sentence 14 or 15, characterized in that the bearing surface (52, 54) on the bearing projection (80) is smaller than on the bearing recess (94) and in that the bearing surfaces (52, 54) are dimensioned such that the The bearing projection (80) in the bearing recess (94) can be rotated about the pivot axis (28) by at least one opening angle (98) of the instrument (10) when the bearing surfaces (52, 54) rest against one another.
17. 17. Medical instrument according to one of sets 10 to 16, characterized in that the first bearing section (64) and the second bearing section (66) interact to form an instrument connection (26).
18. 18. Medical instrument according to sentence 17, characterized in that one of the two bearing sections (66, 68) has a bearing section opening (100) and that the other of the two bearing sections (66, 68) passes through the bearing section opening (100) to form the instrument connection (26) in the form of a push-through closure (48).
19. 19. Medical instrument according to clause 17, characterized in that the first and the second bearing section (66, 68) are designed without any perforations and abut one another to form the instrument connection (26) in the form of an applied connection (50).
20. 20. Medical instrument according to one of the preceding sentences, characterized in that at least one of the two interacting bearing surfaces (52, 54) is rotationally symmetrical, in particular concentric to the pivot axis (28).
21. 21. Medical instrument according to one of the preceding sentences, characterized in that the two interacting bearing surfaces are geometrically (52, 54) similar, in particular of the same size.
22. 22. A method for producing a medical instrument with a first instrument instrument part (12) and at least one second instrument part (14), at least one sliding bearing (46) being formed on the instrument (10) for movably mounting the first instrument part (12) and the at least one second instrument part (14) on one another, the at least a plain bearing (46) is formed with two mutually interacting bearing surfaces (52, 54), characterized in that at least one of the two interacting bearing surfaces (52, 54) of the at least one plain bearing (46) is work-hardened and smoothed by burnishing.
23. 23. The method according to sentence 22, characterized in that at least one of the two bearing surfaces (52, 54) is burnished until a reflectivity of the bearing surface (52, 54) is at least 50% greater than before the burnishing.
24. 24. The method according to sentence 22 or 23, characterized in that at least one of the two bearing surfaces (52, 54) is burnished until the roughness of the bearing surface (52, 54) is smaller than before burnishing, in particular at most about 20 % is, more particularly not more than about 10%.
25. 25. Method according to one of sentences 22 to 24, characterized in that the instrument part (12, 14) on which the bearing surface (52, 54) is burnished is heated to a temperature of at least about 100°C during burnishing.
26. 26. Method according to one of sentences 22 to 25, characterized in that the bearing surface (52, 54) is subjected to a pressure of at least 10 kPa during burnishing.
27. 27. The method according to any one of sentences 22 to 26, characterized in that the bearing surface (52, 54) is machined with a rolling tool (104) and that the rolling tool (104) during smooth rolling about the pivot axis (28) of the instrument (10) is rotated.
28. 28. The method according to sentence 27, characterized in that the rolling tool (104) is rotated in relation to the pivot axis (28) only in one direction of rotation during burnishing.
29. 29. The method according to sentence 27 or 28, characterized in that a rolling tool (104) with at least two, in particular three, rolling elements (110) is used for burnishing and that the at least two rolling elements (110) are cylindrical or truncated.
30. 30. The method according to sentence 29, characterized in that the at least two roller elements (110) are each rotated about a roller axis (112) during burnishing, which runs in a plane (114) perpendicular to the pivot axis (28).
31. 31. Method according to one of sentences 22 to 30, characterized in that the first instrument part (12) is formed with a first bearing section (64), that the at least one second instrument part (14) is formed with a second bearing section (66) and that the cooperating bearing surfaces (52, 54) are formed on the first bearing section (64) and on the second bearing section (66).
32. 32. The method according to sentence 31, characterized in that the first bearing section (64) has at least one first bearing section side (68), that the at least one second bearing section (66) has at least one second bearing section side (70), that the at least one first bearing section side (68) and the at least one second bearing section side (70) point towards one another and on the at least one first bearing section side (68) and on the at least one second bearing section side (70) one of the two interacting bearing surfaces (52, 54) of the at least one plain bearing (46) arranged or formed.
33. 33. The method according to sentence 32, characterized in that a first bearing element (78) is formed on the at least one first bearing section side (68), that a second bearing element (90) is formed on the at least one second bearing section side (70) and that a first bearing element side surface (82) of the first bearing element (78) and a second bearing element side surface (92) of the second bearing element (90) are formed as the two interacting bearing surfaces (52, 54) of the at least one plain bearing (46).
34. 34. The method according to sentence 33, characterized in that the first bearing element (78) and/or the second bearing element (90) are formed by machining, in particular by milling.
35. 35. Use of a method according to one of sentences 22 to 34 for producing a medical instrument (10) according to one of sentences 1 to 21.

• 1: eine schematische Gesamtansicht eines Ausführungsbeispiels eines medizinischen Instruments;
• 2: eine schematische perspektivische Ansicht eines Ausführungsbeispiels eines Instrumententeils beim Glattwalzen einer Lagerfläche;
• 3: eine vergrößerte Teilansicht der Anordnung aus 2;
• 4: eine teilweise geschnittene Ansicht der Anordnung aus 3;
• 5: eine vergrößerte Ansicht des Bereichs A aus 4;
• 6: eine teilweise geschnittene Ansicht der Anordnung aus 4 in Richtung des Pfeils B;
• 7: eine schematische Ansicht ähnlich 2 mit einem alternativen Bearbeitungswerkzeug;
• 8: eine vergrößerte Teilansicht der Anordnung aus 7;
• 9: eine Ansicht analog 4 der Anordnung aus 7;
• 10: eine vergrößerte Ansicht des Bereichs B aus 9;
• 11: eine Ansicht analog 6 der Anordnung aus 9;
• 12: eine schematische Darstellung einer Rauheit einer Lagerfläche vor dem Glattwalzen;
• 13: eine schematische Darstellung einer Lagerfläche nach dem Glattwalzen;
• 14: eine schematische Darstellung einer Teilschnittansicht eines Ausführungsbeispiels eines Gleitlagers mit zwei Lagerflächen;
• 15: eine Teilschnittansicht ähnlich 14 eines weiteren Ausführungsbeispiels;
• 16: eine Teilschnittansicht ähnlich 14 eines weiteren Ausführungsbeispiels;
• 17: eine Schnittansicht im Bereich eines Instrumentenschlusses in Form eines Durchsteckschlusses;
• 18: eine Schnittansicht eines Instrumentenschlusses in Form eines aufgelegten Schlusses; und
• 19: eine schematische Darstellung eines Schlussbereichs eines Instruments mit drei aneinander gelagerten Instrumententeilen.

The following description of a preferred embodiment of the invention is used in connection with the drawing for more detailed explanation. Show it:

• 1 1: a schematic overall view of an exemplary embodiment of a medical instrument;
• 2 1: a schematic perspective view of an exemplary embodiment of an instrument part during burnishing of a bearing surface;
• 3 : an enlarged partial view of the arrangement 2 ;
• 4 : a partially sectioned view of the assembly 3 ;
• 5 : an enlarged view of area A 4 ;
• 6 : a partially sectioned view of the assembly 4 in the direction of arrow B;
• 7 : a schematic view similar 2 with an alternative editing tool;
• 8th : an enlarged partial view of the arrangement 7 ;
• 9 : a view by analogy 4 of the arrangement 7 ;
• 10 : an enlarged view of area B 9 ;
• 11 : a view by analogy 6 of the arrangement 9 ;
• 12 1: a schematic representation of a roughness of a bearing surface before burnishing;
• 13 : a schematic representation of a bearing surface after burnishing;
• 14 : a schematic representation of a partial sectional view of an embodiment of a plain bearing with two bearing surfaces;
• 15 : a partial sectional view similar 14 another embodiment;
• 16 : a partial sectional view similar 14 another embodiment;
• 17 : a sectional view in the area of an instrument closure in the form of a push-through closure;
• 18 : a sectional view of an instrument closure in the form of an applied closure; and
• 19 : a schematic representation of a final area of an instrument with three instrument parts placed one on top of the other.

In 1 an exemplary embodiment of a medical instrument 10 is shown schematically. It comprises a first instrument part 12 and a second instrument part 14.

The instrument parts 12 and 14 are in the form of elongated branches 16 and 18, respectively, at the proximal ends of which a finger ring 20 and 22, respectively, is formed.

The two instrument parts 12 and 14 are movably mounted relative to one another in an end region 24 which defines an instrument end 26 .

At the in 1 illustrated embodiment, the branches 16 and 18 are pivotally mounted about a pivot axis 28 to each other.

Tool elements 30 or 32 are arranged or formed on the instrument parts 12 and 14 on the distal side of the end region 24 . The tool elements 30 and 32 are designed to work together and define a tool 34.

At the in 1 In the exemplary embodiment illustrated, the tool elements 30 and 32 are designed in the form of clamping jaws with clamping surfaces 36 and 38, respectively, pointing towards one another.

Furthermore, in the embodiment of 1 in the transition area of the branches 16 and 18 to the finger rings 20 and 22 a locking device 40 with two interacting locking members 42 and 44 is formed. With the blocking device 40, the instrument parts 12 and 14 can be fixed in an approximate position against opening. The locking device 40 can also be omitted in alternative exemplary embodiments.

The instrument 10 comprises a single plain bearing 46 or two plain bearings 46 for movably mounting the instrument parts 12 and 14. The number of plain bearings 46 depends in particular on whether the instrument connection 26 is designed in the form of a push-through connection 48, which comprises two plain bearings 46, or in the form of an applied conclusion 50 with a plain bearing 46. The 17 and 18 schematically show possible configurations of the end region 24, namely in the form of the push-through closure 48 in 17 and laid-up final 50 in 18 .

Each sliding bearing 46 comprises two cooperating bearing surfaces 52 and 54. The bearing surfaces 52 and 54 rest against one another and slide off one another when the instrument parts 12 and 14 are moved relative to one another.

Various exemplary embodiments of different sliding bearings 46 and bearing surfaces 52 or 54 comprised by them are described in more detail below.

In all of the exemplary embodiments described below, the interacting bearing surfaces 52 and 54 run transversely, namely perpendicularly, to the pivot axis 28.

In the described exemplary embodiments of plain bearings 46, at least one of the two bearing surfaces 52 and 54 is work-hardened and smoothed by burnishing. This processing of the bearing surfaces 52, 54 increases their reflectivity. Consequently, the reflectivity of the work-hardened bearing surface 52, 54 is greater than its reflectivity before processing or greater than the reflectivity of a bearing surface 52, 54 that was not work-hardened and smoothed by burnishing.

12 shows schematically a surface condition of the bearing surface 52, 54 before burnishing. Minima and maxima on the bearing surface 52, 54 are at a distance 56 in a direction transverse to the respective bearing surface 52, 54, ie parallel to the pivot axis 28. The bearing surface 52, 54 is work-hardened and smoothed by the smooth rolling. The result of this processing step is shown schematically in 13 shown. A distance parallel to the pivot axis 28 between minima and maxima on the bearing surfaces 52, 54 is significantly reduced to the distance 58, which is only a maximum of 20% of the distance 56. In the embodiment of 12 and 13 the distance 58 is less than 10% of the distance 56. Consequently, the distance 56 defines a first roughness before burnishing and the distance 58 defines a second roughness 62 after burnishing.

In the exemplary embodiments described, the first instrument part 12 comprises a first bearing section 64 and the second instrument part 14 comprises a second bearing section 66. The cooperating bearing surfaces 52 and 54 are formed on the first bearing section 64 and on the second bearing section 66, respectively.

The first bearing section 64 has one or two first bearing section sides 68 . The second bearing section 66 has one or two second bearing section sides 70 . A first bearing section side 68 and a second bearing section side 70 face each other. Furthermore, one of the two interacting bearing surfaces 52 or 54 of each plain bearing 46 is arranged or formed on each bearing section side 68 or 70, respectively.

The first bearing portion side 68 defines a first bearing portion side surface 72. The second bearing portion side 70 defines a second bearing portion side surface 74.

The 14 and 16 schematically show three different configurations of slide bearings 46 of the instrument 10.

In the embodiment of 14 the bearing surfaces 52 and 54 lie against one another. They each define a bearing surface level 76.

A first bearing element 78 is formed on the first bearing section 64, specifically in the form of a bearing projection 80 protruding from the first bearing section side surface 72. No bearing element is formed on the second bearing section 66. The bearing surface 54 thus forms part of the second bearing section side surface 74. In this exemplary embodiment, the bearing surface 54 can optionally be burnished or not.

The first bearing element 78 defines a first bearing element side surface 82. This forms one of the two interacting bearing surfaces 52, 54 of the plain bearing 46, namely the bearing surface 52. A bearing height 84 of the bearing projection 80 in relation to the first bearing section side surface 72 corresponds in this exemplary embodiment to a distance 86 between the first and second bearing portion side surfaces 72 and 74.

The bearing projection 80 is formed in the shape of a flat cylindrical disk. A diameter 88 in a plane perpendicular to the pivot axis 28 is much larger than the bearing height 84. In the 14 illustrated embodiment a little more than 30 times as large.

In the embodiment of 15 the sliding bearing 46 includes a first bearing element 78 in the form of the bearing projection 80. Furthermore, a second bearing element 90 is formed on the second bearing section 66 on a second bearing section side 70. The second bearing element 90 includes a second bearing element side surface 92 which defines the bearing surface 54 . Consequently, the bearing element side surfaces 82 and 92 each form one of the two bearing surfaces 52 and 54.

In this exemplary embodiment, the second bearing element 90 is in the form of a bearing recess 94 corresponding to the bearing projection 80 in the second bearing section 68 . The second bearing element side surface 92 is set back somewhat into the second bearing section 70 compared to the second bearing section side surface 74 .

The bearing recess 94 has a bearing depth 96 in relation to the second bearing section side face 74 . The bearing height 84 is greater than the bearing depth 96. The distance 86 between the first and second bearing portion side surfaces 72 and 74 is the difference between the bearing height 84 and the bearing depth 96.

The diameter 88 of the bearing elements 78 and 90 is dimensioned such that the instrument parts 12 and 14 can be rotated about the pivot axis 28 relative to one another.

In the exemplary embodiment described, the bearing height is at least approximately 10% greater than the bearing depth 96.

In the embodiment of 16 Both the first and the second bearing element 78, 90 are designed as bearing projections 80. Each of the two bearing projections 80 defines a bearing surface 52 or 54.

A distance 86 between the first and second bearing section side surfaces 72, 74 is defined as the sum of the bearing heights 84 of the two bearing projections 80.

As in the embodiment of 14 are also in the plain bearings 46 of 15 and 16 one or both bearing surfaces 52, 54 work-hardened and smoothed by burnishing.

The bearing surface 52 on the bearing projection 80 of the embodiment of 15 is slightly smaller than the bearing surface 54 on the bearing recess 94. The bearing surfaces 52 and 54 are dimensioned such that the bearing projection 80 in the bearing recess 94 can be rotated about the pivot axis by at least one opening angle 98 of the instrument 10 when the bearing surfaces 52, 54 rest against one another. The opening angle 98 defines a maximum pivoting of the instrument parts 12 and 14 from a position that is as close as possible to a position that is as far away from one another as possible.

As already explained, the bearing sections 64 and 66 work together to form the instrument connection 26 .

In the schematic in 17 A bearing section opening 100 is formed on the first bearing section 66 as shown in the exemplary embodiment of an instrument closure 26 . The second bearing section 68 passes through the bearing section opening 100 to form the instrument connection 26 in the form of the push-through connection 48.

In the embodiment of 18 the two bearing sections 64, 68 are designed without openings and rest against one another or on top of each other to form the instrument connection 26 in the form of the applied connection 50.

In the embodiments of 14 until 19 one or both bearing surfaces 52, 54 are optionally designed to be rotationally symmetrical. In the exemplary embodiments shown, they are configured concentrically to the pivot axis 28 .

Furthermore, the cooperating bearing surfaces 52 and 54 are geometrically similar to each other. In the embodiments of 15 until 19 Are they even the same size or almost the same size?

The embodiment of 19 of the medical instrument 10 comprises a total of three instrument parts 12, 14 and 12'. The instrument parts 12 and 12 ′ are of identical design in the end area 24 . They correspond in structure to the instrument part 12 according to the exemplary embodiment of FIG 14 . Consequently, a bearing projection 80 is formed on each of these instrument parts 12 .

The second instrument part 14 is mirror-symmetrical to a mirror plane 102 running perpendicular to the pivot axis 28 in the end region 24 . A bearing projection 80 protrudes from each of the two second bearing section side surfaces 74 pointing away from one another. The bearing element side surfaces 82 form the cooperating bearing surfaces 52 and 54. Overall, the embodiment according to 19 two plain bearings 46, the plain bearing 46 of the embodiment of the in their structure 18 are equivalent to.

In the 2 until 6 is shown schematically how one of the bearing surfaces 52, 54 on an instrument part 12 is work-hardened and smoothed by burnishing.

First, the instrument part 12 is formed from a blank in such a way that a first bearing element 78 in the form of a bearing projection 80 is formed on the first bearing section side 68 by machining, namely by milling, protruding or protruding from the first bearing section side surface 72.

The instrument part 12 prepared in this way is now processed with a rolling tool 104 . It is rotated about the pivot axis 28 of the instrument 10 during smooth rolling.

In one exemplary embodiment, the rolling tool 104 is only rotated in one direction of rotation with respect to the pivot axis 28 during burnishing, ie either clockwise or counterclockwise.

The rolling tool 104 comprises a shaft 106 which is concentric to the pivot axis and on which rolling elements 110 are arranged on the distal side in a housing 108 and can each be rotated about a roll axis 112 . The roller axes 112 each run in a plane 114 perpendicular to the pivot axis 28.

In the embodiment of 2 until 6 includes the rolling tool 104 three rolling elements 110. These are cylindrical. They are aligned with their roller axes 112 pointing away in the radial direction from the pivot axis 28 and are rotatably mounted on the housing.

The bearing surface 52 or 54 is smooth-rolled with the rolling tool 104 until its reflectivity is at least 50% greater than before the smooth-rolling.

Furthermore, the bearing surface 52, 54 is burnished until its roughness is smaller than before burnishing. In particular, the bearing surface 52, 54 is machined until the roughness is no more than about 20% of the original roughness, in particular no more than about 10%. This has already been discussed above in connection with the 12 and 13 explained as an example.

Furthermore, the instrument part 12, on which the bearing surface 52, 54 is burnished, is heated during burnishing, specifically to a temperature of at least about 100°C.

In order to strengthen the bearing surface 52, 54 as desired, the bearing surface 52, 54 is subjected to a pressure of at least 10 kPa during burnishing.

In the 7 until 11 In an alternative embodiment, the processing of an instrument part 12 to form a smooth-rolled bearing surface 52 is shown schematically. Here you can fully refer to the description of the 2 until 6 to get expelled. The only difference here is the design of the rolling tool 104. This does not include cylindrical rolling tools 110, but rather truncated cone-shaped rolling elements 110. They are arranged in such a way that, starting from the pivot axis 28, they widen in the outer diameter away from it.

The three roll axes 112 do not lie in one plane, as is the case with the rolling tool 104 according to the exemplary embodiment of FIG 2 until 6 is the case, but are inclined relative to the bearing surface 52 by half a cone angle defined by the rolling elements 110 .

With the described rolling tools 104 according to 2 until 11 all bearing surfaces 52, 54 described above can be work-hardened and thus smoothed by burnishing.

As already explained, in the plain bearings 46 either both bearing surfaces 52, 54 or only one bearing surface 52, 54 are work-hardened by burnishing.

As a result of the strain hardening, as in 13 shown schematically, a roughness significantly reduced. However, this process, which otherwise occurs when the instrument 10 is used by frequently moving the instrument parts 12 and 14 relative to one another in an undefined manner, has the advantage that it makes it possible to adjust the instrument parts 12 and 14 relative to one another, for example with a coupling element in the form of a locking screw or a rivet, does not have to be readjusted if the roughness decreases due to wear. The work-hardened bearing surfaces 52, 54 can practically not change any further, so that when the instrument 10 is used, an originally set gait, preferably a "sucking gait" as described, is permanently retained.

Reference List

10

medical instrument

12, 12'

first instrument part

14

second instrument part

16

industry

18

industry

20

finger ring

22

finger ring

24

final area

26

instrument closure

28

pivot axis

30

tool item

32

tool element

34

Tool

36

clamping surface

38

clamping surface

40

locking device

42

locking member

44

locking member

46

bearings

48

push-through closure

50

imposed conclusion

52

storage area

54

storage area

56

Distance

58

Distance

60

first roughness

62

second roughness

64, 64'

first camp section

66

second storage section

68, 68'

first bearing section side

70

second bearing section side

72, 72'

first bearing portion side surface

74

second bearing portion side surface

76

storage area level

78

first bearing element

80

bearing projection

82

first bearing element side surface

84

storage height

86

Distance

88

diameter

90

second bearing element

92

second bearing element side surface

94

bearing recess

96

storage depth

98

opening angle

100

bearing section breakthrough

102

mirror plane

104

rolling tool

106

shaft

108

Housing

110

rolling element

112

roller axis

114

level

Claims (15)

Medical instrument (10) with a first instrument part (12) and at least one second instrument part (14), wherein the instrument (10) comprises at least one plain bearing (46) for movably supporting the first instrument part (12) and the at least one second instrument part ( 14) to one another, wherein the at least one plain bearing (46) comprises two bearing surfaces (52, 54) that interact with one another, characterized in that at least one of the two bearing surfaces (52, 54) that interact with one another of the at least one plain bearing (46) is work-hardened and smoothed by burnishing is. Medical instrument after claim 1 , characterized in that the first instrument part (12) and the at least one second instrument part (14) are mounted on one another so as to be pivotable about a pivot axis (28), the two interacting bearing surfaces (52, 54) in particular being transverse, in particular perpendicular, to the pivot axis ( 28) run. Medical instrument according to one of the preceding claims, characterized in that a reflectivity of the at least one work-hardened bearing surface (52, 54) is greater than the reflectivity of a non-work-hardened bearing surface (52, 54) or of a non-work-hardened surface area of the instrument (10). Medical instrument according to one of the preceding claims, characterized in that the instrument (10) comprises a) only two instrument parts (12, 14), namely a first instrument part (12) and a second instrument part (14), or b) three instrument parts ( 12, 14), namely a first instrument part (12) and two second instrument parts (14). Medical instrument according to one of the preceding claims, characterized in that a first roughness of the at least one work-hardened bearing surface (52, 54) is smaller than a second roughness of a non-work-hardened bearing surface (52, 54) or a non-work-hardened surface area of the instrument (10) , wherein in particular the first roughness is at most about 20% of the second roughness, in particular at most about 10%. Medical instrument according to one of the preceding claims, characterized in that the first instrument part (12) comprises a first bearing section (64), that the at least one second instrument part (14) comprises a second bearing section (66) and that the interacting bearing surfaces (52, 54) are formed on the first bearing section (64) and on the second bearing section (66). Medical instrument after claim 6 , characterized in that the first bearing section (64) has at least one first bearing section side (68), that the at least one second bearing section (66) has at least one second bearing section side (70), that the at least one first bearing section side (68) and the at least one second bearing section side (70) face each other and that on the at least one first bearing section side (68) and on the at least one second bearing section side (70) each have one of the two interacting bearing surfaces (52, 54) of the at least one slide bearing (46) is arranged or formed. Medical instrument after claim 7 , characterized in that the at least one first bearing section side (68) comprises a first bearing element (78), that the at least one second bearing section side (70) comprises a second bearing element (90), that the first bearing element (78) has a first bearing element side surface (82 ) comprises that the second bearing element (90) comprises a second bearing element side surface (92) and that the first bearing element side surface (82) and the second bearing element side surface (90) each have one of the two interacting bearing surfaces (52, 54) of the at least one plain bearing (46) form, in particular the first bearing section side (68) a) defining a first bearing section side surface (72), the second bearing section side (70) defining a second bearing section side surface (74) and the first bearing element (78) and/or the second bearing element (90 ) in the form of a bearing projection (80) protruding from the respective bearing section side surface (72, 74) or b) one first bearing section side surface (72), that the second bearing section side (70) defines a second bearing section side surface (74) and wherein the first bearing element (78) is in the form of a bearing projection (80) projecting from the first bearing section side surface (72) and that the second Bearing element (90) is designed in the form of a bearing recess (94) corresponding to the bearing projection (80), in particular - the bearing projection (80) has a bearing height (84) in relation to the first bearing section side surface (72) and the bearing recess (94) has a bearing depth ( 96) in relation to the second bearing section side surface (74) and that the bearing height (84) is greater than the bearing depth (96), in particular at least 10% greater, and/or - the bearing surface (52, 54) on the bearing projection (80) is smaller is than at the bearing recess (94) and that the bearing surfaces (52, 54) are dimensioned such that the bearing projection (80) in the bearing recess (94) about the pivot axis (28) be i abutting bearing surfaces (52, 54) by at least one opening angle (98) of the instrument (10) is rotatable. Medical instrument according to one of Claims 6 until 8th , characterized in that the first bearing section (64) and the second bearing section (66) interact to form an instrument connection (26), with in particular a) one of the two bearing sections (66, 68) having a bearing section opening (100) and the other the two bearing sections (66, 68) pass through the bearing section opening (100) to form the instrument connection (26) in the form of a push-through connection (48) or b) the first and the second bearing section (66, 68) are formed without openings and rest against one another for formation of the instrument ending (26) in the form of an applied ending (50). Method for producing a medical instrument with a first instrument part (12) and at least one second instrument part (14), wherein at least one sliding bearing (46) is formed on the instrument (10) for movably mounting the first instrument part (12) and the at least one second one instrument part (14) to one another, the at least one plain bearing (46) being formed with two mutually interacting bearing surfaces (52, 54), characterized in that at least one of the two interacting bearing surfaces (52, 54) of the at least one plain bearing (46) is smooth rolling is work hardened and smoothed. procedure after claim 10 , characterized in that at least one of the two bearing surfaces (52, 54) is burnished until a) a reflectivity of the bearing surface (52, 54) is at least 50% greater than before burnishing and/or b) a roughness of the bearing surface (52, 54) is smaller than before burnishing, in particular still at most about 20%, further in particular still at most about 10%. procedure after claim 10 or 11 , characterized in that a) the instrument part (12, 14) on which the bearing surface (52, 54) is burnished is heated to a temperature of at least approximately 100°C during burnishing and/or b) the bearing surface (52, 54) is subjected to a pressure of at least 10 kPa during burnishing. Procedure according to one of Claims 10 until 12 , characterized in that the bearing surface (52, 54) is machined with a rolling tool (104) and that the rolling tool (104) is rotated about the pivot axis (28) of the instrument (10) during smooth rolling, with in particular a) the rolling tool (104) during burnishing is only rotated in one direction of rotation relative to the pivot axis (28) and/or b) a rolling tool (104) with at least two, in particular three, rolling elements (110) is used for burnishing and that the at least two rolling elements (110) are designed cylindrically or in the shape of a truncated cone, wherein in particular the at least two rolling elements (110) are each rotated about a roller axis (112) during burnishing, which runs in a plane (114) perpendicular to the pivot axis (28). Procedure according to one of Claims 10 until 13 , characterized in that the first instrument part (12) is formed with a first bearing section (64), that the at least one second instrument part (14) is formed with a second bearing section (66) and that the interacting bearing surfaces (52, 54) on first bearing section (64) and on the second bearing section (66), in particular the first bearing section (64) having at least one first bearing section side (68), the at least one second bearing section (66) having at least one second bearing section side (70) which at least one first bearing section side (68) and the at least one second bearing section side (70) pointing towards one another and on the at least one first bearing section side (68) and on the at least one second bearing section side (70) one of the two interacting bearing surfaces (52, 54) of the at least one slide bearing (46) are arranged or formed, with further in particular on the at least A first bearing element (78) is formed on at least one first bearing section side (68), on the at least one second bearing section side (70) a second bearing element (90) is formed and a first bearing element side surface (82) of the first bearing element (78) and a second bearing element side surface (92) of the second bearing element (90) are formed as the two interacting bearing surfaces (52, 54) of the at least one plain bearing (46), with the first bearing element (78) and/or the second bearing element (90) in particular also being machined , In particular by milling, are formed. Use of a method according to one of Claims 10 until 14 for the production of a medical instrument (10) according to one of Claims 1 until 9 .

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