Semi-finished and medical instruments

Abstract

The present invention provides an improved semi-finished medical instrument comprising an instrument body blank made of metal, in particular instrument steel, for forming an instrument body of a medical instrument, a distal end region, and a recess for accommodating a hard metal element provided in the distal end region, the recess having an abutment surface for the hard metal element, and in particular, it is proposed that the instrument body blank comprises a solder chamber for accommodating solder, the solder chamber being fluidly connected to the recess, so that the instrument's susceptibility to corrosion is reduced. Additionally, improved medical devices have been proposed.

Description

[Technical field]

[0001] The present invention relates to semi-finished instruments comprising an instrument body part blank made of metal, in particular instrument steel, for forming an instrument body part of a medical instrument, a distal end region and a recess for accommodating a hard metal element on the distal end region, the recess having an abutment face for the hard metal element.

[0002] The present invention further relates to a medical device comprising at least one device body portion. [Background technology]

[0003] Semi-finished instruments and medical devices of the initially mentioned kind are known in a wide variety of embodiments, for example being used as needle holders for grasping, holding and guiding surgical needles.

[0004] A needle holder usually comprises two instrument body parts in the forms of branches, pivotably attached to each other and configured at their distal ends in the shape of mouth parts which form clamping jaws between which a needle can be held. Summary of the Invention [Problem to be solved by the invention]

[0005] It is particularly important for the needle holder to be able to hold the needle between the mouth parts in a completely slip-resistant and tilt-resistant manner. The surfaces of the clamping jaws are therefore usually of structured configuration. In order to keep the wear of the clamping jaws' structure, also called profile, as minimal as possible, it is common for needle holders to use hard metal jaws that are configured in the form of hard metal platelets and are connected to the mouth parts so as to form at least part of the lateral surfaces of the clamping jaws facing each other.

[0006] The hard metal platelets forming the hard metal insert can be joined to the metal tool body part, for example by soldering, in particular by brazing. Even if the hard metal insert is correctly positioned at room temperature, relative movements during joining often occur. In other words, in the worst case, the solder between the hard metal insert and the tool body part is not in its original starting position before being placed in the hardening oven, which leads to a large solder gap in the transition region between the hard metal insert and the tool body part. However, this kind of solder gap has a negative effect on the quality of the solder connection. In particular, it can lead to the occurrence of defects, cracks or brittle phases lacking mechanical strength.

[0007] Furthermore, there is a problem that the amount of solder present in the solder gap between the hard metal insert and the instrument body portion is not sufficient for diffusion of the solder into both the material from which the instrument body portion blank is formed and into the hard metal insert, resulting in the formation of defects, cavities, and pores.

[0008] To avoid this problem, a lot of extra solder is generally applied from the outside. However, in this case, the hard metal insert must be manufactured much larger than the final mouth shape of the instrument and soldered to the instrument body part blank. However, in the oversized production, the hard metal insert must be ground to the desired dimensions, which is time-consuming and costly.

[0009] After the connection between the hard metal insert and the device body part blank, both the excess solder and the overhang of the hard metal insert need to be elaborately reworked by a manual grinding process, with the risk of overheating the material forming the device body part blank, thereby making the medical device more susceptible to corrosion.

[0010] Moreover, an excess of solder can cause further problems. Thus, chromium is known to chemically bond with the solder, due to its high affinity with the solder additives commonly used. This can therefore lead to a depletion of chromium in the diffusion area of ​​the material forming the instrument body part blank. In particular, this effect can occur in the case of martensitic stainless steels, such as material 1.4021. An undesirable consequence of chromium depletion is the corrosion of the instrument in the area of ​​the material forming the instrument body part blank, especially due to the subsequent action of strong cleaning agents by the user. Furthermore, it is necessary to prevent the excess solder from spreading into gaps and surfaces. This is because, during soldering, in the worst case, the two mouth parts of the instrument may be soldered together when they are held together in the hardening oven. To prevent this, before soldering, these parts that may come into contact with the hardening solder must be thoroughly coated with a material called solder stop, which prevents the solder from penetrating.

[0011] Thus, the entire known process of connecting hard metal inserts to the appliance body part blanks, i.e. the soldering process, is very labor intensive and therefore costly, as the process involves many partial manual operations and therefore a low process safety.

[0012] SUMMARY OF THE DISCLOSURE The object of the present invention is therefore to improve semi-finished instruments and medical instruments of the initially mentioned kind, in particular so as to reduce the susceptibility of the instruments to corrosion.

[0013] This object is achieved according to the invention in a semifinished tool of the initially mentioned kind in that the tool body part blank is provided with a solder chamber for receiving solder, and in that the solder chamber is fluidly connected to the recess. [Means for solving the problem]

[0014] The solution proposed by the invention allows, in particular, the amount of solder to be precisely predetermined. This is achieved in particular by predetermining the shape and size of the solder chamber. When the solder chamber is completely filled with solder, the amount of solder is precisely predetermined. As a result of the solder chamber being fluidically connected to the recess which accommodates the hard metal element, the solder can be drawn out of the solder chamber by capillary action into the solder gap between the hard metal element and the abutment surface during hardening. If the capillary action disappears, the solder will no longer flow. Thus, the problems of excessive surplus solder currently used and of uncontrollable solder flow can be avoided. By predetermining the solder chamber, i.e. its volume, the solder can be precisely injected, so that the coding of the tool body part blank by soldering and the typical many overhangs of the hard metal insert on the tool body part blank can be omitted. The subsequent expenditure required for the processing of the semifinished tool, in particular by grinding, is thereby significantly reduced. Moreover, the provision of a solder chamber, which may in particular be arranged or formed in the instrument body part blank, so that the hard metal insert can be removed therefrom after soldering into the recess of the instrument body part blank, has the advantage that the hard metal insert can be soldered to the instrument body part blank in its final or substantially final form. For example, the hard metal insert may be configured in the form of a hard metal platelet that is already structured in the desired way, i.e. has a structured or profiled surface that is optimal for holding needles, or otherwise defines the desired shape, for example with a chamfer on the side. Thereby, the further processing costs for forming the semi-finished instrument can be significantly reduced. In particular, the described further development is advantageous when connecting the hard metal platelet forming the hard metal insert to the instrument body part formed by metal by a vacuum high-temperature soldering process. The large temperature difference during the hardening process, which is carried out at about 1000 ° C, and the difference in the thermal expansion coefficients of the instrument body part and the hard metal insert do not lead to defects, cracks or brittle phases lacking in mechanical strength.

[0015] The semi-finished tool preferably comprises a hard metal element, which may for example be of platelet-shaped configuration or have a structured or profiled surface, in particular the hard metal element may already have its final form and does not need to be further processed, in particular by polishing, after being connected to the tool body part blank.

[0016] The hard metal element is preferably in a platelet-shaped configuration, such that it can be handled in a simple manner and can be reliably connected to the instrument body part blank in the described manner by soldering.

[0017] The hard metal element preferably has a soldering surface for placement against the abutment surface such that when the hard metal element is connected to the appliance body part blank a solder gap is formed between the soldering surface and the abutment surface and capillary action draws solder from the solder chamber into the solder gap.

[0018] Preferably, the hard metal element is inserted into the recess and connected to the instrument body part blank by soldering, a permanent and reliable connection between the hard metal insert and the instrument body part blank is thus achieved.

[0019] In particular, an optimal connection between the hard metal insert and the device body part blank is achieved by a solder layer formed between the abutment surface and the soldering surface. The solder layer is preferably continuous and uninterrupted, so that the abutment surface and the soldering surface are completely separated from each other by the solder layer. The thickness of the solder layer may in particular be less than 0.05 mm.

[0020] According to a further preferred embodiment of the invention, it may be provided that the hard metal element has a tool side face, the tool side face and the soldering face facing in opposite directions. In particular, a flat hard metal platelet can be formed, which forms the hard metal element. The tool side face, e.g. a profiled or structured surface of the hard metal element for gripping and holding a needle, can already be provided in the desired form before connecting to the instrument body part blank.

[0021] Depending on the type of element to be formed, the tool side surface is preferably of planar or substantially planar configuration or is structured. In particular, the tool side surface may be provided with a macroscopic structure, where macroscopic means that the depressions or protrusions of the tool side surface are larger than about 0.1 mm.

[0022] In particular, tool sides with a regular structure allow the construction of the semi-finished device to be simplified and, moreover, the needle can be held in a defined manner using an instrument, for example a needle holder.

[0023] It is advantageous if the structure has a plurality of projections and recesses formed therebetween, which in particular allows a secure holding of the needle between two clamping jaws of the medical instrument, in particular the projections being able to partially bite into the needle and the recesses being able to partially accommodate the needle.

[0024] In particular, a good holding effect can be achieved by means of pyramidal protrusions, which may in particular be configured in the shape of a triangular or quadrangular pyramid.

[0025] Furthermore, it is preferred that the hard metal element has at least one side edge extending transversely to the tool side surface, and a chamfer is formed in the transition area between the tool side surface and the at least one side edge. In particular, the chamfer may be formed at an angle ranging from about 35 degrees to about 55 degrees. As already explained at the beginning, the processing of the hard metal insert after the connection to the instrument body part blank is associated with a risk of subsequently increasing the sensitivity of the instrument to corrosion. The described configuration of the instrument body part blank therefore has the advantage that the hard metal insert can be provided in its final form for a pre-determined amount of solder resulting from a pre-determined solder chamber. Subsequent chamfering of the hard metal insert to avoid sharp edges, which was necessary or carried out in the conventional configuration of the medical instrument, is no longer necessary with the hard metal element already in the corresponding configuration.

[0026] It is advantageous if two chamfers are formed on the hard metal element which run parallel or substantially parallel to each other or towards each other in the direction towards the distal end. The hard metal element formed in this way can in particular be connected to a recess on the distally tapering instrument body part blank. This allows the distally tapering mouth part to be formed on the medical instrument in a simple manner.

[0027] If the solder chamber comprises or is configured in the form of a hole, the device body blank can be manufactured in a simple manner, and the volume of the solder chamber can therefore be predetermined in a simple manner, i.e. by the length and diameter of the bore.

[0028] According to a further preferred embodiment of the invention, it may be provided that the solder chamber defines a solder chamber longitudinal axis, the recess defines a recess longitudinal axis, and that the solder chamber longitudinal axis and the recess longitudinal axis extend parallel or substantially parallel to one another. Such an arrangement allows in particular a simple handling of the instrument body part blank. Furthermore, the solder chamber can be filled with solder in a simple manner before the hard metal insert is soldered to the instrument body part blank. This is particularly simple when the solder chamber is formed on a protrusion of the instrument body part blank which extends in a distal direction, for example away from the recess which accommodates the hard metal insert.

[0029] In order to ensure the flow of solder in the desired manner from the solder chamber between the abutment surface and the soldering surface, i.e. into the solder gap, it is advantageous if the solder chamber is fluidically connected to the recess by a lateral connection extending transversely, in particular perpendicularly, to the solder chamber longitudinal axis.

[0030] If the transverse connection is designed in the form of a transverse bore, the semi-finished device can be produced in a simple manner.

[0031] In order to impede the flow of solder between the soldering surface and the abutment surface as little as possible, the lateral connection preferably passes through the abutment surface: the solder can flow from the solder chamber through the lateral connection directly into the solder gap.

[0032] The handling of the device body part blank and the construction of the semi-finished device are further simplified, in particular by arranging or forming a solder chamber at the distal end of the device body part blank, which can therefore be filled with solder in a simple manner, and by a corresponding arrangement, the hard metal insert can furthermore be connected to the device body part blank and then optionally removed in a simple manner.

[0033] According to a further preferred embodiment of the invention, it may be provided that the tool body part blank comprises a solder chamber part, the solder chamber being arranged or formed in the solder chamber part and the solder chamber part being configured to be separable from the tool body part blank. The solder chamber part is therefore only a temporary part of the tool body part blank. It can therefore be removed, in particular after the hard metal insert has been soldered to the tool body part blank. This is achieved by separating the solder chamber part from the remaining tool body part blank. The solder chamber part is therefore initially formed integrally with the tool body part blank and forms part of it, and its role is to accommodate the solder in the solder chamber arranged or formed in the solder chamber part, in particular for soldering the hard metal insert to the tool body part blank. After soldering, the solder chamber is emptied and is no longer needed. It can then be separated, for example by sawing, grinding or milling. This is possible in a simple manner if a bottleneck or constriction, for example a predefined breaking point, is formed between the solder chamber part and the remaining tool body part blank.

[0034] Preferably, the recess has a first end face and a second end face, the first end face extending transversely to the abutment face and the second end face extending transversely to the abutment face, the first end face and the second end face facing each other or substantially facing each other, such a configuration of the recess makes it possible in particular to delimit the movement of the hard metal element accommodated in the recess, i.e. between the first and second end faces, before forming the solder connection.

[0035] In order to be able to insert the hard metal element into the recess in a defined manner, it is advantageous if the first end face or the second end face together with the abutment face defines an undercut, so that the hard metal element can be placed in the recess in the desired way, i.e. without further assistance, In particular, the distance of the hard metal element from the abutment face and thus the width of the solder gap can thus be predetermined in a simple and reproducible manner.

[0036] It is preferred that the contour of the first end face and the contour of the second end face are different from each other. This makes it possible, in particular, to configure the recess in such a way that a clear position of the hard metal element in the recess is predefined. The hard metal element can thus be arranged in the tool body part blank in a defined manner. The remaining play therefore ensures, in particular, that the hard metal element can be used in the desired manner, without still having to be elaborated after being soldered to the tool body part blank.

[0037] It is advantageous if the first end face and / or the second end face are of planar or substantially planar configuration or are concavely curved towards each other. In particular, the first end face and / or the second end face may be of concavely curved configuration with respect to an axis of curvature extending transversely to the abutment face. Furthermore, the first end face and the second end face may be of different configuration, whereby the hard metal element can be accommodated in the recess in a positive-locking or substantially positive-locking manner, except for possibly remaining play. The curvatures of the first end face and the second end face may in particular be different from each other, so that a defined position of the hard metal element in the recess can be predetermined.

[0038] It is advantageous if a coupling receptacle is formed on the instrument body part blank for receiving a coupling projection which projects from the hard metal element and is formed in particular in a manner of positive locking, the coupling receptacle being able to cooperate with the coupling projection on the hard metal element to clearly position the hard metal element in the recess. In particular, a movement of the hard metal element relative to the instrument body part blank in a plane parallel to the abutment surface or parallel to the soldering surface can be effectively prevented. In particular, an at least partial positive locking coupling between the instrument body part blank and the hard metal element can be achieved by cooperation of the coupling receptacle with the coupling projection.

[0039] The coupling receptacle is preferably arranged or formed in the solder chamber part, which makes it possible to separate the coupling receptacle together with the solder chamber part, in particular after soldering the hard metal element to the device body part blank.

[0040] It is advantageous if the hard metal element is provided with a protruding connecting projection and if the connecting projection is configured to be separable from the hard metal element, in particular so that the connecting projection can be separated after the hard metal element has been soldered to the tool body part blank, so that only the hard metal element, in particular with its tool side, remains on the tool body part blank to form the semi-finished tool.

[0041] In order to easily separate the connecting projection from the hard metal element, it is preferred that the thickness, in particular the average thickness, of the hard metal element is smaller in the region of the connecting projection than in the region of the tool side.

[0042] According to a further preferred embodiment of the invention, it may be provided that the coupling receptacle has a coupling receptacle abutment surface and that the coupling projection has a coupling projection soldering surface for placement against the coupling receptacle abutment surface. This arrangement makes it possible to couple the hard metal element and the device body part blank to one another by soldering, in particular also in the region of the coupling receptacle and the coupling projection. Optionally, the distance between the coupling receptacle abutment surface and the coupling projection soldering surface may be selected such that no capillary action occurs which draws solder between these two surfaces.

[0043] The coupling receptacle abutment surface and the abutment surface preferably define a common abutment plane.Such an arrangement enables the device body part blank to be formed in a simple manner.

[0044] In particular, it is preferred that the transverse connection passes through the coupling receptacle abutment surface in order to improve the stability of the semi-finished device. This configuration also allows the transverse connection to be removed when the solder chamber part is removed after connecting the hard metal element to the device body part blank. In particular, it is possible to prevent cavities remaining in the semi-finished device after soldering the hard metal element to the device body part blank, which may have a negative effect on the stability of the device.

[0045] Furthermore, it may be preferred that the tool body part blank comprises a predetermined breaking point, which is arranged or formed for the separation of the solder chamber, in particular the solder chamber part, from the tool body part blank. Such a predetermined breaking point in particular facilitates the separation of the solder chamber, in particular together with the solder chamber part, from the tool body part blank. Thus, that part of the tool body part blank which is only necessary for defining the amount of solder for connecting the hard metal element to the tool body part blank can be removed in a simple and reliable manner after soldering of the hard metal element to the tool body part blank.

[0046] The predetermined breaking point can be formed in a simple manner if it is in the form of a weakened region between the distal end of the device body portion and the solder chamber portion.

[0047] The tool body part blank is preferably formed by cold forming or hot forming. Tool body part blanks of this kind can be formed in a simple and well-defined manner.

[0048] The initially mentioned object is further achieved by the invention in a medical device of the initially mentioned kind in that at least one device body part is formed by one of the advantageous semi-finished devices described above.

[0049] Such medical devices can be formed in the advantageous manner described above and, unlike conventional medical devices in which metal inserts are soldered to the device body blank, are significantly less susceptible to corrosion.

[0050] It is advantageous if the hard metal element and the instrument body part are connected to each other by soldering, the solder chamber, in particular the solder chamber part, is separated, and the distal end of at least one instrument body part is treated by grinding, milling or polishing. As mentioned above, the hard metal element can be provided in substantially its final form, in particular to be soldered to the instrument body part blank. This is made possible by the fact that, as a result of the solder chamber, in particular the amount of solder required to solder the hard metal element and the instrument body part blank to each other is provided precisely. In a preferred embodiment of the medical instrument, the treatment of the instrument body by grinding, milling or polishing is only necessary in the area where the solder chamber part is provided, i.e. to separate the solder chamber part. Such treatment can be visibly detected in the finished medical instrument.

[0051] It is advantageous if the medical instrument comprises two instrument body parts in the form of branches which are movably connected to each other. For example, they may be displaceably attached to each other. Also, for example, they may be pivotally attached to each other about a common pivot axis. Various instruments can thus be formed, for example clamps or needle holders.

[0052] Manufacturing of the medical device is further simplified, in particular by the fact that the hard metal elements of the two device body portions are of identical construction.

[0053] Advantageously, the tool side of the two identical hard metal elements each has a macroscopic structure with a number of projections and recesses formed between them, the projections of one of the two closest hard metal elements each engaging in the recesses of the other hard metal element and the outer contours of the two closest hard metal elements covering each other in a coincident or substantially coincident manner. The projections and recesses, also called tooth tips and tooth roots, can thus interengage with each other in the closest position, in particular in the closed position of the tool. Due to the special arrangement of the regular structure of projections and recesses, unlike what is known from the prior art, there is no lateral offset of the two cooperating hard metal elements, but instead they can be covered in a coincident manner with each other in the closest position. The macroscopic structure of the two hard metal elements may in particular be of a regular configuration.

[0054] The two instrument body parts can be connected to one another in a simple manner by means of a connecting screw or joint pin, or by riveting, pressing or welding, which can in particular define a pivot axis and can also predetermine the play of the two instrument body parts relative to one another.

[0055] Preferably, the medical instrument is configured in the form of a needle holder, which allows for secure gripping, holding and handling of surgical needles, and which is more resistant to corrosion than needle holders known from the prior art.

[0056] The following description of preferred embodiments of the present invention works in conjunction with the drawings for further explanation. [Brief description of the drawings]

[0057] [Figure 1] FIG. 1 is an overall perspective view showing a schematic embodiment of a medical device; [Diagram 2] FIG. 1 is a partial perspective view showing a schematic representation of an instrument body part blank prior to the insertion of a hard metal element into a receptacle on the instrument body part blank; [Diagram 3] FIG. 3 is a view similar to FIG. 2 but showing a hard metal element inserted into a recess on the instrument body portion blank; [Figure 4] FIG. 2 shows a schematic longitudinal section of an embodiment of a tool body part blank with a hard metal element inserted during filling of the solder chamber with solder; [Diagram 5] FIG. 5 is a schematic diagram showing the arrangement from FIG. 4 during soldering of the appliance body part blank and the hard metal element; [Figure 6] FIG. 5 is a schematic cross-sectional view similar to FIG. 4 of a further embodiment; [Figure 7] FIG. 2 is a perspective view showing a schematic embodiment of a hard metal element; [Figure 8] 1 is a schematic cross-sectional view of a distal end region of an embodiment of a medical device; [Figure 9] FIG. 2 shows a schematic perspective view of a further embodiment of a hard metal element [Figure 10] FIG. 2 shows a schematic perspective view of a further embodiment of a hard metal element [Figure 11] FIG. 2 shows a schematic perspective view of a further embodiment of a hard metal element [Figure 12] FIG. 5 is a cross-sectional view similar to FIG. 4 of a further embodiment having a recess on a tool body part blank with an undercut on one side. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0058] A first embodiment of a medical device 10 is shown generally in Figure 1 and designated generally by the reference numeral 10. The device 10 is configured in the form of a needle holder 12.

[0059] The instrument 10 comprises two instrument body portions 14 and 16 movably coupled to one another. In an embodiment, the instrument body portions 14 and 16 are connected to one another in a known manner by a connecting screw 18. The connecting screw 18 defines a pivot axis 20 about which the instrument body portions 14 and 16 can pivot relative to one another.

[0060] Instrument body portions 14 and 16 are configured in the form of branches 22 and 24 having respective finger rings 26 and 28 disposed at their proximal ends.

[0061] Disposed between the proximal ends of branches 22 and 24 is a locking device 30 for preventing movement of the proximal ends of instrument body portions 14 and 16 away from one another. Locking device 30 is configured such that locking can be achieved for different spacings of the proximal ends of branches 22 and 24.

[0062] The instrument body parts 14 and 16 are connected to one another at a connection region 32 by means of a connection screw 18. The connection region 32 is configured in the form of a push-through connection.

[0063] Distal to the connection region 32, the device body portions 14 and 16 define mouthpieces 34 and 36.

[0064] The mouth parts 34 and 36 each have a recess 38 and 40 which receives a respective hard metal element 42 and 44. The hard metal elements 42 and 44 are connected to the respective instrument body portions 14 and 16 by soldering.

[0065] The distal ends 46 and 48 of the instrument body portions 14 and 16 are prepared by grinding and / or polishing.

[0066] As shown diagrammatically in FIG. 1, needle holder 12 grasps, holds, and guides needle 50 to form a stitch.

[0067] The recesses 38 and 40 are arranged and formed so as to face each other in the finished device 10. In other words, when the device 10 is closed, i.e. when the mouthparts 34 and 36 are maximally moved towards each other, the hard metal elements 42 and 44 face each other and abut each other in the closed position, and the needle 50 can be held between the hard metal elements 42 and 44.

[0068] Device body portions 14 and 16 are each formed from a semi-finished device 52. The construction and manufacture of semi-finished device 52 is described in detail below with reference to Figures 2-12.

[0069] 2 shows, by way of example, a distal end region 56 of the instrument body section blank 54. The instrument body section blank 54 is formed from a metal. In one embodiment, the metal is an instrument steel.

[0070] The device body section blank 54 has a recess 38 formed in a distal end region 56. The semi-finished device 52 is formed from the device body section blank 54 and will form the device body section 14 upon completion.

[0071] The recess 38 serves to accommodate the hard metal element 42 and defines an abutment surface 58 for the hard metal element 42. The abutment surface 58 is planar in this embodiment.

[0072] The recess 38 has a first end surface 60 and a second end surface 62. The first end surface 60 extends transversely relative to the abutment surface 58. The second end surface 62 extends transversely relative to the abutment surface 58. Moreover, the first end surface 60 and the second end surface 62 face each other or substantially face each other.

[0073] In the embodiment of the instrument body section blank 54 shown in Figure 2, the contours of the first end face 60 and the second end face 62 are different from one another. Moreover, in the embodiment of the instrument body section blank 54 shown in Figure 2, both the first end face 60 and the second end face 62 are formed concavely curved relative to one another, i.e., relative to first and second axes of curvature 64 and 66 that extend transversely, in particular perpendicularly, to the abutment surface 58.

[0074] The device body portion blank 54 further includes a solder chamber 68 which contains solder 70 .

[0075] The solder chamber 68 is disposed or formed at a distal end 72 of the instrument body portion blank 54 .

[0076] The device body portion blank 54 includes a solder chamber portion 74 for locating or forming the solder chamber 68 .

[0077] The solder chamber portion 74 is of separable construction and can be removed from the instrument body portion blank 54 after the hard metal element 42 is soldered to the instrument body portion blank 54, as described below.

[0078] The solder chamber portion 74 is configured in the form of a substantially cuboidal body 76 extending the distal end region 56 of the instrument body portion blank 54. The solder chamber 68 is configured in the form of a bore 78, the solder chamber longitudinal axis 80 of which extends parallel or substantially parallel to a longitudinal axis 82 of the instrument body portion blank 54 in the region of the distal end region 56. The longitudinal axis 82 extends parallel to the recess longitudinal axis defined by the recess 38, such that the solder chamber longitudinal axis 80 and the recess longitudinal axis 84 extend parallel or substantially parallel to each other.

[0079] The solder chamber 68 is fluidly connected to the recess 38. In the embodiment shown in Figure 2, this is accomplished by a lateral connection 86 that extends transversely, i.e. perpendicular to the solder chamber longitudinal axis.

[0080] The lateral connection 86 is configured in the form of a lateral hole 88. The lateral connection 86 also passes through the abutment surface 58.

[0081] In the embodiment of the instrument body portion blank 54 shown in FIG. 2, a mating receptacle 90 is also formed to receive a mating projection 92 formed extending from the hard metal element 42 .

[0082] A mating receptacle 90 is disposed or formed in the solder chamber portion 74. It has a mating receptacle abutment surface 94 which defines a common abutment plane 96 with the abutment surface 58.

[0083] In the embodiment of the device body section blank 54 shown in FIGS. 2-4, the transverse connection 86 passes through the mating receptacle abutment surface 94 .

[0084] In the embodiment of the hard metal element 42 shown in Figures 2 to 4, the coupling protrusions 92 are configured to correspond to the coupling receptacles 90 such that, when the hard metal element 42 is inserted into the recess 38, as shown, for example, in Figure 3, the coupling protrusions 92 are received in the coupling receptacles 90 in a positive-locking or substantially positive-locking manner.

[0085] The hard metal element 42 is in a platelet-shaped configuration and has a soldering surface 98 for placement against the abutment surface 58 .

[0086] However, in order to solder the hard metal element 42 to the tool body part blank 54, a narrow solder gap 100 is formed between the abutment surface 58 and the soldering surface 98. The width of the solder gap 100 is at most about 0.05 mm to allow capillary action to occur in the solder 70. After soldering the hard metal element 42 and the tool body part blank 54, a thin solder layer 102 is formed between the abutment surface 58 and the soldering surface 98. Its thickness corresponds approximately to the width of the solder gap 100.

[0087] The hard metal element 42 also has a tool side 104. The tool side 104 and the soldering surface 98 face in opposite directions.

[0088] In the embodiment of the hard metal element 42 shown in Figures 2 and 3, the tool side 104 is a structured configuration and has a macroscopic structure 106. The structure 106 of the tool side 104 is a regular configuration. The structure 106 has a number of protrusions 108 with depressions 110 formed therebetween.

[0089] In one embodiment, the protrusion 108 is a pyramidal configuration. In one embodiment, it is configured as a three-sided pyramid or a four-sided pyramid.

[0090] The hard metal element 42 has two side edges 112 and 114 extending transversely to the tool side surface 104. In particular, in the embodiment shown in Figures 9 to 11, respective chamfers 116 and 118 are formed in the transition areas between the tool side surface 104 and the respective side edges 112 and 114.

[0091] The enclosed angle 120 between the tool side 104 on the one hand and the plane bounding the chamfers 116 and 118 on the other hand ranges between about 35 degrees and about 55 degrees.

[0092] In some embodiments, the chamfers 116 and 118 extend parallel to one another, while in other embodiments they extend toward one another in a direction toward the distal end 122 of the tool side 104 .

[0093] The hard metal element 42 has a mating projection soldering surface 124 in the region of the mating projection 92 for positioning against the mating receptacle abutment surface 94. In particular, as shown in Figures 2 to 4, the mating projection soldering surface 124 is positioned opposite the transverse hole 88 passing through the mating receptacle abutment surface 94.

[0094] The manufacture of the semi-finished product 52 is explained in more detail below in relation to FIGS.

[0095] The hard metal element 42 is inserted into the recess 38 as previously described, i.e. so that the coupling projection 92 engages with the coupling receptacle 90 in a positive-locking manner. An edge 126 of the hard metal element 42 facing proximally abuts against the first end face 60 or is separated therefrom by a narrow gap. An edge 128 of the coupling projection 92 facing distally likewise abuts against the second end face 62.

[0096] The solder chamber 68 is filled with solder paste 70 starting from the end 72. For this purpose, the spout 130 of a tube 132 filled with solder 70 is inserted into the hole 78 and the solder 70 is forced into the solder chamber 68, as shown, for example, in FIG.

[0097] The solder chamber 68 is sized to accommodate exactly the amount of solder needed to solder the hard metal element 42 and the device body section blank 54 together without excess.

[0098] Soldering is performed under high temperature in a vacuum, i.e. in a hardening oven at about 1000° C. The solder 70 is drawn from the solder chamber 68 into the solder chamber 100 as a result of the capillary action of the solder gap 100. At the end of the solder gap 100, i.e. between the first end face 60 and the second edge 126, the capillary action gradually disappears and the solder flow stops. The solder flow is interrupted all around, i.e. between the side edges 112 and 114 and the abutment face 58. As a result, unlike the prior art, there is no uncontrolled solder flow and both the coating with solder stop and the substantial overhang of the hard metal element 42 over the device body part blank 54 can be omitted.

[0099] The hard metal element 42 has its final form apart from the coupling projections 90. As mentioned above, the chamfers 116 and 118 can already be formed on the hard metal element 42 before soldering, thus eliminating the need to manually chamfer the hard metal element 42 after soldering to the instrument body part blank 54.

[0100] As a result of the positive locking engagement of the coupling projection 92 into the coupling receptacle 90 and the particular design of the first end face 60 formed corresponding to the corresponding edge 126, a defined position between the hard metal element 42 and the instrument body portion blank 54 can be ensured, thereby making it possible to prevent a large proportion of their displacement relative to one another during soldering.

[0101] After soldering, the solder chamber portion 74 is separated from the device body portion blank 54. To facilitate this, a predetermined break point 134 is formed at which the solder chamber portion can be separated or broken by applying force. The coupling projection 92 is then also separated from the hard metal element 42 along with the solder chamber portion 74.

[0102] After separation of the solder chamber portion 74 and the coupling projection 92, the distal end of the instrument body portion blank 54 and the distal end of the hard metal element 42 are finished by grinding and polishing.

[0103] The semi-finished instrument 52 is now complete and the instrument body portion 14 can be further movably joined to the instrument body portion 16 configured in the manner described, i.e., with the hard metal element 44, to form the instrument 10.

[0104] In one embodiment, the predetermined break point 134 is configured in the form of a weakened area 136 , ie, between the end 46 of the device body portion 14 and the solder chamber portion 74 .

[0105] The tool body section blank 54 is formed by cold forming or hot forming.

[0106] To simplify the separation of the coupling projection from the hard metal element 42 , the thickness, in particular the average thickness, of the coupling projection 92 is smaller than the area of ​​the tool side surface 104 .

[0107] Shown in FIG. 6 is an embodiment having a tool element 42 that is structured and has a plurality of protrusions 108 and depressions 110 arranged or formed in a regular pattern.

[0108] In contrast, in the embodiment of the hard metal element 42 shown in Figures 4 and 5, the tool side 104 is of planar or microstructured configuration.

[0109] 7 shows an embodiment of the hard metal element 42 without the coupling projection 92. The edge 128 is concavely curved in the distal direction and transitions to the side edges 112 and 114 in a manner without kinks or edges. The edge 126 is of planar configuration. In particular, it may be formed slightly inclined with respect to the soldering surface 98 in order to engage with the undercut formed in the recess 38. Due to the different shapes of the edges 126 and 128 corresponding to the end faces 16 and 62 in the embodiment of the instrument body part blank 54 not shown in the figures, a defined position of the hard metal element 42 can also be achieved during soldering to the instrument body part blank 54.

[0110] The hard metal element 42 shown in Figure 7 has a structure 106 such that the hard metal element 42 can be disposed in both the instrument body portion 14 and the instrument body portion 16. The recesses 110 and the protrusions 108 are interengaged to correspond with each other. Thus, only a single type of hard metal element 42 is needed to form the semi-finished instrument 52 for forming the instrument body portions 14 and 16.

[0111] Further embodiments of the hard metal elements 42 are shown by way of example in Figures 9 to 11. In particular, they differ in the configuration of the edges 126.

[0112] In the embodiment of FIG. 9, edge 126 defines an angled configuration having two edge portions 138 and 140 extending transversely to solder surface 98 and angled toward one another to form a proximally facing tip 142.

[0113] In the embodiment of FIG. 10, edge 126 is concavely curved in the proximal direction.

[0114] In the embodiment of FIG. 11, edge 126 is planar, but subtends an angle 144 with solder surface 98 that is less than 90 degrees, and specifically ranges between about 60 degrees and approximately 90 degrees.

[0115] 12, the beveled edge 126 may engage an undercut 146 in the recess 38. The undercut 146 is bounded by the first end surface 60 and the abutment surface 58. The angle 144 ideally coincides with the angle defined by the undercut 146.

[0116] The undercuts defined in relation to Figures 11 and 12 may also be provided in the other hard metal elements 42 described above, ie optionally at their proximal or distal ends.

[0117] As a result of forming an external solder chamber 68 on the instrument body blank 54 as described above, which is removed after soldering the hard metal element 42 to the instrument body blank 54, weakening of the completed mouth parts 34 and 36 is prevented. As explained, precise dose and flow control of the solder by capillary action to the desired joining surfaces is possible.

[0118] For example, the solder chamber 68 can be removed in a simple manner as described above, with a predetermined break point 134 provided for this purpose, for example by a taper or narrowing between the solder chamber portion 74 and the distal end of the recess 38 or 40.

[0119] The proposed further development makes it possible to produce ready-to-fit hard metal elements having a tool-specific shape that do not require significant further processing after soldering to the respective tool body part blank 54.

[0120] As a result of the proposed approach, a higher product quality can be achieved by improving the safety of the process and reducing manual steps. This leads to a reduction in production costs, especially since waste and labor can be reduced. An important advantage is also to prevent the problems of corrosion of the tools with the user related to production, as initially mentioned as a result of traditional soldering methods. Furthermore, a higher stability of the tools can be achieved due to the reduction of stress peaks, reducing the associated risk of breakage. [Explanation of symbols]

[0121] 10. Equipment 12 Needle holder 14 Instrument body part 16 Instrument body part 18 Connection screw 20 Pivot axis 22 Branch 24 Branch 26 Finger Ring 28 Finger Ring 30 Locking device 32 Connection Area 34 Mouth parts 36 Mouth parts 38 Recess 40 Recess 42 Hard Metal Elements 44 Hard Metal Elements 46 End 48 End 50 stitches 52 Semi-finished appliances 54 Blank of the instrument body 56 Edge area 58 Contact surface 60 1st end face 62 Second end face 64 1st axis of curvature 66 Second axis of curvature 68 Soldering Chamber 70 Solder 72 End 74 Solder chamber part 76 Main Body 78 holes 80 Solder chamber longitudinal axis 82 Solder chamber longitudinal axis 84 Recess Longitudinal Axis 86 Horizontal Connection 88 Side Cave 90 Mating Receptacle 92 Combination protrusion 94 Mating receptacle contact surface 96 Contact plane 98 Soldering surface 100 Solder Gap 102 Solder layer 104 Tool side 106 Structure 108 Protrusion 110 Hollow 112 Side edge 114 Side edge 116 Chamfering 118 Chamfering 120 angle 122 End 124 Joint protrusion soldering surface 126 Edge 128 Edge 130 Spout 132 Tube 134 Predetermined Breaking Point 136 Vulnerable Area 138 Edge part 140 Edge part 142 Tip 144 angle 146 Undercut

Claims

1. a device body portion blank (54) formed of metal for forming the device body portions (14, 16) of the medical device (10); a distal end region (56); a recess (38, 40) in said distal end region (56) for receiving a hard metal element (42, 44); Equipped with the recesses (38, 40) have abutment surfaces (58) for the hard metal elements (42, 44); The device body portion blank (54) includes a solder chamber (68) for receiving solder (70); the solder chamber (68) is fluidly connected to the recess (38); The device body portion blank (54) includes a solder chamber portion (74); The solder chamber (68) is disposed or formed in the solder chamber portion (74); The solder chamber portion (74) is configured to be separable from the device body portion blank (54). Semi-finished appliance (52).

2. comprising hard metal elements (42, 44); The semi-finished device (52) of claim 1.

3. The hard metal elements (42, 44) are at least one of the following: (a) a plate-shaped configuration; (b) having a soldering surface (98) disposed against the abutment surface (58); (c) being inserted into said recesses (38, 40) and connected to said device body portion blank (54) by soldering; A semi-finished device (52) according to claim 2.

4. The hard metal elements (42, 44) have a tool side (104); said tool side surface (104) and said soldering surface (98) facing in opposite directions; A semi-finished device (52) according to claim 3.

5. the hard metal element (42, 44) has at least one side edge (112, 114) extending transversely to the tool side surface (104); a chamfer (116, 118) is formed in the transition area between the tool side surface (104) and the at least one side edge (112, 114); A semi-finished device (52) according to claim 3 or 4.

6. The solder chamber (68) is at least one of the following: (a) comprising or configured in the form of a hole (78); and, (b) disposed or formed at a distal end (72) of said instrument body portion blank (54); A semi-finished device (52) according to any one of claims 1 to 5.

7. The solder chamber (68) defines a solder chamber longitudinal axis (80); The recess (38, 40) defines a recess longitudinal axis (84); the solder chamber longitudinal axis (80) and the recess longitudinal axis (84) extend parallel to one another; A semi-finished device (52) according to any one of claims 1 to 5.

8. The solder chamber (68) is fluidly connected to the recesses (38, 40) by transverse connections (86) extending transversely to the solder chamber longitudinal axis (80). A semi-finished device (52) according to claim 7.

9. The recess (38, 40) has a first end surface (60) and a second end surface (62); The first end surface (60) extends transversely to the abutment surface (58). The second end surface (62) extends transversely to the abutment surface (58); The first end surface (60) and the second end surface (62) face each other. A semi-finished device (52) according to any one of claims 1 to 8.

10. a coupling receptacle (90) is formed in the instrument body portion blank (54) for receiving a coupling projection (92) projecting from said hard metal elements (42, 44); A semi-finished device (52) according to any one of claims 1 to 9.

11. The instrument body portion blank (54) comprises: (a) comprising a predetermined break point (134), said predetermined break point (134) being positioned or formed for the purpose of separating said solder chamber (68) from said device body portion blank (54); and / or (b) formed by cold forming or hot forming; A semi-finished device (52) according to any one of claims 1 to 10.

12. At least one instrument body portion, The at least one tool body portion (14, 16) is formed from a semi-finished tool (52) according to any one of claims 1 to 11. A medical device (10).

13. At least one of the following: (a) the hard metal elements (42, 44) and the instrument body portions (14, 16) are connected to one another by soldering; The solder chamber (68) is separated from the instrument body portion blank (54); the distal end of said at least one instrument body portion (14, 16) is treated by grinding, milling or polishing; and, (b) the medical instrument (10) comprises two instrument body portions (14, 16) in the form of branches (22, 24) movably coupled to one another; The medical device (10) according to claim 12.

14. the hard metal elements (42, 44) of the two instrument body portions (14, 16) are of identical construction; The medical device (10) according to claim 13.

15. the tool side (104) of the two identical hard metal elements (42, 44) each having a structure (106), each of said structures (106) having a number of protrusions (108) and a number of recesses (11) formed therebetween; a protrusion of one of the two closest hard metal elements (42, 44) engages with a recess of the other hard metal element (42, 44); the outer contours of the two closest hard metal elements (42, 44) match and interlock; The medical device (10) according to claim 14.

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