APPARATUS FOR EXTRUDING A STRUCTURED EXTRUDATE

Abstract

According to the invention an apparatus for extrusion of a structured extrudate, which can be introduced into a human or animal body, is provided. This apparatus comprises an extrusion apparatus with a housing, whereas the housing has a revolving lateral wall which at a front end in the direction of production is provided with a nozzle wall with an outlet nozzle, and in the direction of production prior to that with a global sleeve, whereas the space in the housing between the global sleeve, the lateral wall and the outlet nozzle confines an extrusion space, and the housing in the region of the extrusion space can be connected to a polymer feeding appliance. In the global sleeve at least one guide channel extending in the direction of production is provided in order to be able to insert at least one rod-shaped body from a feeding appliance for rod-shaped bodies into the extrusion space, whereas the at least one guide channel is arranged in about straight alignment to the outlet nozzle.

Claims

1-20. (canceled)

21. Apparatus for extrusion of a structured extrudate, comprising: a housing, whereas the housing provides a revolving lateral wall which at a front end in the direction of production provides a nozzle wall with an outlet nozzle, and at the back end contrary to the direction of production provides a global sleeve, whereas the space in the housing between the global sleeve, the lateral wall and the outlet nozzle confines an extrusion space, and the housing in the region of the extrusion space can be connected to a polymer feeding appliance, wherein, the global sleeve provides at least one guide channel extending in the direction of production in order to insert at least one rod-shaped body from a feeding appliance for rod-shaped bodies into the extrusion space, and the at least one guide channel is arranged about in straight alignment relative to the outlet nozzle, whereas the at least one guide channel has an essentially constant conicity over its entire lengthand wherein the guide channel extends along the entire length of the global sleeve in the direction of productions.

22. Apparatus according to claim 21, wherein, at least one peripheral guide channel is provided besides the central guide channel, which has an essentially constant conicity over its entire length.

23. Apparatus according to claim 21, wherein, the central guide channel and/or the peripheral guide channel have a contoured cross section which is elliptic or oval or bean-shaped or trapezoidal or three- or four- or multi-cornered.

24. Apparatus according to claim 23, wherein, the peripheral guide channel is angled relative to the direction of production with an angle of 0 to 30, or of 2.5 to 15, resp., and in particular of 5 to 10.

25. Apparatus according to claim 21, wherein, at least three peripheral guide channels are provided concentrically surrounding the central guide channel.

26. Apparatus according to claim 21, wherein, an inner surface/wall of a guide channel has a surface roughness RA1.0 m.

27. Apparatus according to claim 21, wherein, an opening of the central guide channel at the front end in the direction of production has a diameter of 0.2 mm to 0.4 mm and in particular of 0.3 mm, whereas an opening of the central guide channel at the back end in the direction of production has a diameter of 2.0 mm to 4.0 mm and in particular of 3.0 mm.

28. Apparatus according to claim 22, wherein, an opening of a peripheral guide channel at the front end in direction of production has a diameter of 0.1 mm to 0.3 mm and in particular of 0.2 mm, whereas an opening of a peripheral guide channel at the back end in direction of production has a diameter of 3.0 mm to 5.0 mm and in particular of 4.0 mm.

29. Apparatus according to claim 21, wherein, the nozzle wall and the global sleeve in the region of the extrusion space are provided as a conically tapered frustum in the direction of production, whereas the frustum of the global sleeve provides a concave jacketing relative to the extrusion space and the nozzle wall provides a convex jacketing relative to the extrusion space.

30. Apparatus according to claim 21, wherein, the outlet nozzle provides a melt channel, whereas the melt channel is provided as a ring-shaped frustum with a configuration wall which conically tapers in the direction of production, which in the cross section in particular are wavy or jagged, resp., with indentations and protrusions, whereas these contours are called grooves.

31. Apparatus according to claim 30, wherein, these grooves at an end of the outlet nozzle in the direction of production transition into a ring-shaped cross section.

32. Apparatus according to claim 31, wherein, the number of contoured grooves corresponds to the number of peripheral guide channels 9, whereas preferably the indentations are arranged in straight axial alignment with the guide channels.

33. Apparatus according to claim 21, wherein, in the direction of production beyond the outlet nozzle a cooling unit, particularly a water bath for cooling of the guidewires or catheters is provided, and/or that in the direction of production beyond the cooling unit a take-off unit is provided which is provided in order to hold a structured extrudate under tension, and/or that in the direction of production beyond the cooling unit an alignment unit and/or that in the direction of production prior to the housing an appliance for feeding of rod-shaped bodies is provided.

34. Rod-shaped body, comprising: one or more non-metallic filaments, and a non-ferromagnetic matrix material, whereas the matrix material encloses and/or agglutinates the filaments, wherein, the rod-shaped body has a contoured cross section which is elliptic or oval or bean-shaped or trapezoidal or three- or four- or multi-cornered.

35. Method for extrusion of a structured extrudate, in which at least one rod-shaped body is fed into an extrusion apparatus in the direction of production by means of an appliance for feeding of rod-shaped bodies, and within the extrusion apparatus is enclosed by a polymer, and during release from an outlet nozzle of the extrusion apparatus in the direction of production obtains its final shape, wherein, the at least one rod-shaped body is guided by a guide channel with an essentially constant conicity within the extrusion apparatus until the region in the direction of production in front of the outlet nozzle into the extrusion space and is aligned.

36. Method according to claim 35, wherein, during feeding of at least two rod-shaped bodies the gaps between the rod-shaped bodies are impinged with polymer, whereby these are embedded in the polymer.

37. Method according to claim 35, wherein, at least one rod-shaped body is inserted into a peripheral guide channel of the global sleeve of the extrusion apparatus with an angle of 0 to 30, or of 2.5 to 15, resp., and in particular of 5 to 10.

38. Method according to claim 34, wherein, feeding occurs via the central guide channel and/or the peripheral guide channel, whereas at least one of these guide channels has a contoured cross section which is elliptic or oval or bean-shaped or trapezoidal or three- or four- or multi-cornered.

39. Method according to claim 35, wherein, the apparatus comprises a housing, whereas the housing provides a revolving lateral wall which at a front end in the direction of production provides a nozzle wall with an outlet nozzle, and at the back end contrary to the direction of production provides a global sleeve, whereas the space in the housing between the global sleeve, the lateral wall and the outlet nozzle confines an extrusion space, and the housing in the region of the extrusion space can be connected to a polymer feeding appliance, wherein, the global sleeve provides at least one guide channel extending in the direction of production in order to insert at least one rod-shaped body from a feeding appliance for rod-shaped bodies into the extrusion space, and the at least one guide channel is arranged about in straight alignment relative to the outlet nozzle, whereas the at least one guide channel has an essentially constant conicity over its entire length. and wherein the guide channel extends along the entire length of the global sleeve in the direction of productions.

40. Method according to claim 35, wherein, one or more rod-shaped body(ies) is used, the rod-shaped body(ies) comprising one or more non-metallic filaments, and a non-ferromagnetic matrix material, whereas the matrix material encloses and/or agglutinates the filaments, wherein, the rod-shaped body has a contoured cross section which is elliptic or oval or bean-shaped or trapezoidal or three- or four- or multi-cornered.

Description

[0229] In the following the invention will be illustrated by reference to the drawings. These show in:

[0230] FIG. 1 a schematic representation of the global sleeve according to the present invention for extrusion of a structured extrudate, wherein the body of the global sleeve is illustrated transparent so that the guide channels are visible,

[0231] FIG. 2 a laterally cut view of the global sleeve according to the present invention with a central guide channel and a peripheral guide channel,

[0232] FIG. 3 a schematic representation of an apparatus according to the present invention with the global sleeve according to the present invention,

[0233] FIG. 4 a schematic representation of a nozzle wall according to the present invention in a laterally cut view,

[0234] FIG. 5 a perspective view of a melt channel of an outlet nozzle according to the present invention,

[0235] FIG. 6 an entry opening of the melt channel in a top view,

[0236] FIG. 7 an alternative embodiment of an entry opening of the melt channel in a top view,

[0237] FIG. 8 a schematic representation of a cross section perpendicular to the direction of production of a global sleeve according to the present invention in the region of an alignment opening with a central guide channel and six peripheral guide channels or, resp., a schematic representation of a medical instrument with a number of rod-shaped bodies corresponding to the number of guide channels,

[0238] FIG. 9 another embodiment of a cross section perpendicular to the direction of production of a global sleeve according to the present invention in the region of an alignment opening with a central multi-cornered guide channel and six elliptic peripheral guide channels in a schematic representation or, resp., a schematic representation of a medical instrument with a number of rod-shaped bodies corresponding to the number of guide channels,

[0239] FIG. 10 another embodiment of a cross section perpendicular to the direction of production of a global sleeve according to the present invention in the region of an alignment opening with a central round guide channel and six peripheral elliptic guide channels in a schematic representation or, resp., a schematic representation of a medical instrument with a number of rod-shaped bodies corresponding to the number of guide channels,

[0240] FIG. 11 another embodiment of a cross section perpendicular to the direction of production of a global sleeve according to the present invention in the region of an alignment opening with a central round guide channel and six peripheral trapezoidal guide channels in a schematic representation or, resp., a schematic representation of a medical instrument with a number of rod-shaped bodies corresponding to the number of guide channels,

[0241] FIG. 12 another embodiment of a cross section perpendicular to the direction of production of a global sleeve according to the present invention in the region of an alignment opening with a central trapezoidal guide channel and six elliptic peripheral guide channels in a schematic representation or, resp., a schematic representation of a medical instrument with a number of rod-shaped bodies corresponding to the number of guide channels,

[0242] FIG. 13 another embodiment of a cross section perpendicular to the direction of production of a global sleeve according to the present invention in the region of an alignment opening with a central guide channel and six peripheral guide channels in a schematic representation or, resp., a schematic representation of a medical instrument with a number of rod-shaped bodies corresponding to the number of guide channels,

[0243] FIG. 14 another embodiment of a cross section perpendicular to the direction of production of a global sleeve according to the present invention in the region of an alignment opening with a central round guide channel and six peripheral elliptic guide channels in a schematic representation or, resp., a schematic representation of a medical instrument with a number of rod-shaped bodies corresponding to the number of guide channels, and

[0244] FIG. 15 another embodiment of a cross section perpendicular to the direction of production of a global sleeve according to the present invention in the region of an alignment opening with a central round guide channel and six trapezoidal peripheral guide channels in a schematic representation or, resp., a schematic representation of a medical instrument with a number of rod-shaped bodies corresponding to the number of guide channels.

[0245] According to the present invention an apparatus 12 for extrusion of a structured extrudate, in particular a medical instrument which can be introduced into a human or animal body, is provided (FIG. 3).

[0246] The apparatus 12 comprises a housing, whereas the housing provides a revolving lateral wall 13, the front end in the direction of production 3 with a nozzle wall 14 with an outlet nozzle 15 and the back end in the direction of production 3 with a fixation ring 16, a bushing element 17 and a global sleeve 1.

[0247] The fixation ring 16 is provided ring-shaped and comprises in the direction of production 3 a transit opening 18 which transitions in the direction of production 3 from a conically tapering section into a cylindrical section. On the outside or radially circumferentially, resp., the fixation ring has two revolving steps 19.

[0248] Via the transit opening 18 the rod-shaped bodies reach the global sleeve 1, whereby they do not contact the wall of the transit opening.

[0249] In the direction of production 3 in front of the fixation ring 16 is arranged the pipe-like bushing element 17.

[0250] A ring section 5 preformed at the global sleeve 1 is fixed in the region between the bushing element 17 and the fixation ring 16. Fixation of the global sleeve 1 is realized by screwing together the fixation ring 16 with the lateral wall 13. In this way the ring section 28 of the global sleeve 1 is clamped between the fixation ring 16 and the bushing element.

[0251] Preferably a means, such as e.g. a dowel pin, is provided at the global sleeve 1 in order to ensure a self-alignment of the global sleeve in an angle position relative to the direction of production in a respective alignment to the nozzle wall.

[0252] The dowel pin may gear into a respective recess of the fixation ring.

[0253] Alternatively the global sleeve may be freely adjustable around the direction of production or, resp., in its angle position relative to the direction of production in a rotating manner or also in grid steps with an angle offset of 1 to 60, or 2, or 5, or 10, or 15, or 30, or 45, resp. Once the fixation ring 16 and the lateral wall 13 are connected to each other, e.g. by a screw connection, the global sleeve is arranged stationary in the housing.

[0254] One front surface of the bushing element 17 is such concavely chamfered that the melt flows in the direction of production between the lateral wall 13 and the global sleeve. The front surface of the bushing element 17 confines the extrusion space opposite to the direction of production 3.

[0255] At the front surface in the direction of production the front wall, the lateral wall is connected to the nozzle wall, e.g. by means of a screw connection. Herein it may also be provided that the nozzle wall in the direction of production is rotatable or, resp., adjustable also in grid steps with an angle offset of 1 to 60, or 2, or 5, or 10, or 15, or 30, or 45, resp.

[0256] In the following the global sleeve 1 is described. The global sleeve 1 has a cylindrical section 2 and in the direction of production 3 a connecting truncated cone type section 4 (FIG. 1 and FIG. 2).

[0257] At a back end of the global sleeve 1 in the direction of production 3 the ring section 5, shaped as a step, is preformed, by means of which the global sleeve can be fixed in the housing.

[0258] In the global sleeve 1 in axial alignment relative to the direction of production 3 a conically shaped central guide channel 6 is provided.

[0259] The central guide channel 6 has an essentially constant conicity.

[0260] At a back end of the central guide channel 6 in the direction of production 3 the channel openings are called feeding openings 7. The openings at the front end of the guide channel in the direction of production are called alignment openings 8.

[0261] The opening of the guide channel 6 at its front end in the direction of production or the alignment opening 8, resp., have a diameter of 0.2 mm to 0.4 mm and in particular 0.3 mm.

[0262] The opening of the guide channel 6 at its back end in the direction of production or the feeding opening 7, resp., have a diameter of 2.0 mm to 4.0 mm and in particular 3.0 mm.

[0263] Furthermore, the global sleeve 1 has at least one peripheral guide channel 9 arranged besides the central guide channel 6. The peripheral guide channel 9 equally has a constant conicity over its entire length.

[0264] At a front end of the peripheral guide channel 9 in the direction of production 3 the opening is called a peripheral alignment opening 10 and has a diameter of 0.1 mm to 0.3 mm and in particular of 0.2 mm.

[0265] At a back end of the peripheral guide channel 9 in the direction of production 3 the opening is called a peripheral feeding opening 11 and has a diameter of 3.0 mm to 5.0 mm and in particular of 4.0 mm.

[0266] The peripheral guide channel 9 is angled relative to the direction of production 3 with an angle of 0 to 30, or of 2.5 to 15, resp., and in particular of 5 to 10. This tilting relates to a middle axle of the conical peripheral guide channel in the direction of production.

[0267] If more than six peripheral rods shall be fed, also more steep angles relative to the direction of production may be provided in order to be able to appropriately arrange the openings 11 opposite to the direction of production of the peripheral guide channels 9. if required the diameter of these openings 11 may be reduced. It may also be provided that further parameters of the apparatus, such as e.g. diameter of the guide channels, diameter of the global sleeve, diameter of the distribution circle for the openings 11 of the guide channels 9 in the direction of production 3 and also opposite to it may be modified.

[0268] An inner surface or wall, resp., of the central guide channel 6 and of the peripheral guide channel 9 provide a surface roughness R.sub.A smaller or equal to 1.0 m.

[0269] According to another embodiment of the global sleeve 1 according to the present invention (FIG. 1, FIG. 2) within the global sleeve 1 a central guide channel 6 and three or six, resp., peripheral guide channels 9, concentrically surrounding the central guide channel 6 and radially uniformly arranged apart from each other, are provided. The peripheral guide channels 9 are arranged relative to the direction of production 3, or relative to the central guide channel 6, resp., with a distance of 60 to each other.

[0270] The global sleeve 1 is surrounded by the lateral wall 5, whereas a step preformed in the lateral wall 5 attaches to a front wall of the bushing element 17.

[0271] In the following the other components of the apparatus are described (FIG. 3 to FIG. 7).

[0272] The nozzle wall 14 is connected to the lateral wall 13 at the front end in the direction of production 3. The connection can be in such a way that the nozzle wall may be adjustable in its angle position relative to the direction of production in predetermined intervals or even freely.

[0273] The space between the global sleeve 1, the bushing element 17, the lateral wall 13 and the nozzle wall 14 confine the extrusion space 20.

[0274] The nozzle wall 14 in the region of the extrusion space 20 conically tapers in the direction of production 3 and thereby is provided as a ring-shaped frustum. This frustum provides a convex jacketing relative to the extrusion space 20.

[0275] The curvature of the jacketing of the frustum 4 of the global sleeve preferably corresponds to the curvature of the nozzle wall 14. This means that these are provided in a corresponding manner in order to create a constant annular gap between the frustum 4 of the global sleeve and the frustum 26 of the nozzle wall 14. Accordingly, the jacketing of the frustum 4 of the global sleeve is provided concave relative to the extrusion space in order to correspond (concave/convex) with the convex nozzle wall 14 or its frustum 26, resp.

[0276] The distance or the annular gap, resp., between the conical section 4 of the global sleeve 1 and the frustum 26 of the nozzle wall is 1.0 to 10 mm, or 1.0 mm to 5 mm, resp., or 1.0 mm to 3.0 mm, resp., or 1.0 to 2.0 mm, resp.

[0277] The concave wall 4 and the concave wall 26 can thus be defined as concentric circles relative to a center point located outside of the apparatus 12. The diameter of these circles is in the range between 100 and 200 mm and preferably between 130 mm and 160 mm.

[0278] In alternative, not preferred, embodiments the walls of the conical sections 4, 26 of the global sleeve 1 and the nozzle wall 14 may also be provided flat/convex, convex/flat, flat/flat, flat/concave, concave/flat, concave/concave.

[0279] The outlet nozzle 15 comprises a melt channel 22, whereas the melt channel 22 conically tapers in the direction of production 3 as a ring-shaped frustum 21 with an alignment wall 23. An opening of the melt channel 22 positioned opposite to the direction of production 3 is called an entry opening 24. An opening of the melt channel 22 positioned in the direction of production 3 is called an outlet opening 25.

[0280] The entry opening 24 may be provided in particular as being wavy or jagged in the cross section. The resulting contours extending in the direction of production 3 are called grooves 27.

[0281] The outlet opening 25 may be provided in particular as being circular in the cross section.

[0282] A section of the outlet opening may be shaped cylindrically over a length of about 1 mm in order to ensure a straightforward discharge of the extrudate from the apparatus.

[0283] Accordingly, grooves 27 in the direction of production 3 are provided in the alignment wall 23 of the melt channel 22 extending from the wavy cross section of the entry opening 24, whereas the grooves 27 then transition into the circular cross section of the outlet opening 25. Therefore, the outlet nozzle 15 is called a structured outlet nozzle 15.

[0284] The number of contoured grooves 27 may preferably correspond to the number of peripheral guide channels 9, 10, 11.

[0285] Preferably the grooves 17 are offset relative to the peripheral guide channels 9, 10, 11 by half the offset angle of these.

[0286] The contour of the alignment wall 23, therefore, may be triangular in the cross section with indentations in the sides, or flower-shaped, resp. In particular the number of petals corresponds to the number of peripheral guide channels 9.

[0287] Preferably the apparatus according to the present invention is provided for manufacturing of structured extrudates with e.g. a central and two to ten and preferably three to six peripheral rod-shaped bodies. According to the mechanical requirements for the structured extrudate a central rod-shaped body and several peripheral rod-shaped bodies may be provided. Generally any desired arrangement of rod-shaped bodies with or without a central rod-shaped body is possible.

[0288] The apparatus according to the invention may also be used for manufacturing of tubes or catheters with e.g. three to then rod-shaped bodies which are arranged in the tube or catheter wall.

[0289] A system for extrusion of a structured extrudate comprises along a direction of production an appliance for feeding the rod-shaped bodies, such as e.g. a material tree (not displayed), the apparatus, a cooling unit, such as e.g. a water bath (not displayed), an alignment unit (not displayed) and a take-off unit (not displayed). The apparatus comprises the extrusion space 3 into which a melt or polymer feeding appliance joins.

[0290] Preferably between the cooling unit and the take-off unit an alignment unit is provided.

[0291] In the following various embodiments of the central guide channel 6 and the peripheral guide channel 9 are described. The central guide channel 6 and the peripheral guide channels 9 may have a contoured cross section which is oval or bean-shaped, or three- or four- or multi-cornered, trapezoidal or elliptic. The displayed details are schematic drawings and concern a region in the global sleeve 1 about in the region of the alignment opening 8. A structured extrudate manufactured with such a global sleeve 1 provides exactly such an arrangement of the rod-shaped bodies 29 in the cross section of the structured extrudate 30.

[0292] According to another embodiment the global sleeve 1 comprises a central guide channel 6 with a hexagonal cross section, whereas the edges of the hexagon are provided convex relative to a plane perpendicular to the direction of production 3 (FIG. 8). In the region of the convex edges of the hexagonal central guide channel 6 radially revolving and equally apart from each other each one elliptic peripheral guide channel 9 is arranged so that in total in the global sleeve six peripheral guide channels 9 are arranged.

[0293] According to another embodiment of the global sleeve the central guide channel 6 provides a hexagonal cross section with equal edge lengths, whereas in the region of the edges of the hexagon the central guide channel 6 radially revolving and equally apart from each other each six peripheral guide channels 9 with elliptic cross section are provided (FIG. 9).

[0294] According to another embodiment the central guide channel 6 is provided with a round cross section, whereas also radially equally apart from each other six peripheral guide channels 9 with elliptic cross section are provided (FIG. 10).

[0295] According to another embodiment the central guide channel 6 is provided with a round cross section, whereas the peripheral guide channels 9 are provided with an about trapezoidal cross section (FIG. 11). The trapezoidal cross section of the peripheral guide channels 9 is provided in such a way that the edges of the trapezoid running in radial direction relative to the direction of production are arranged about in parallel to each other and the two edges of the trapezoid running about in parallel to each other are provided in concave shape in vertical direction relative to the direction of production.

[0296] According to another embodiment of the global sleeve it comprises a central guide channel 6 with a pentagonal cross section, whereas the edges of the pentagon are provided in concave shape relative to the direction of production (FIG. 12). Similar to the embodiment as described in FIG. 8 five peripheral guide channels are provided, which are arranged in the region of the edges of the central guide channel 6, and whereas an edge formed along the edge of the central guide channel 6 of the peripheral guide channels 9 relative to the direction of production may be provided in convex shape (FIG. 12).

[0297] According to another embodiment the central guide channel 6 may be provided as an equilateral polygon, in particular a pentagon. Accordingly, five peripheral guide channels with elliptic cross section are provided, the edges of which are provided in concave shape relative to a plane vertical to the direction of production 3 (FIG. 13).

[0298] According to another embodiment of the global sleeve 1 the central guide channel 6 is round, whereas radially circumferential and equally apart from each other five elliptic peripheral guide channels 9 are provided, the edges of which are provided in convex shape relative to a plane vertical to the direction of production 3 (FIG. 14).

[0299] According to another embodiment which essentially corresponds to the embodiment as described in FIG. 11 instead of six peripheral guide channels also five peripheral guide channels 9 with about trapezoidal shape may be provided which are equally apart from each other (FIG. 15).

[0300] A global sleeve 1 according to the present invention comprises usually a central guide channel 6 with a cross section provided round or multi-cornered, whereas the edges of the polygon are provided in convex or concave shape relative to a plane vertical to the direction of production 3.

[0301] Furthermore such a global sleeve 1 comprises at least three or four or five or six or seven or eight or nine or more peripheral guide channels 9 which are shaped elliptic, polygonal, trapezoidal, and whereas their edges relative to the direction of production are concavely or convexly shaped.

[0302] In the region of the entry openings 7, 11 the radial distances of the peripheral guide channels 9 towards each other may be larger or wider, resp. The same applies for the distances of the peripheral guide channels 9 towards the central guide channel 6.

[0303] In the following a method according to the present invention for manufacturing of guidewires or catheters to be introduced into the human or animal body is described as an example by reference to a guidewire in which seven rod-shaped bodies are arranged.

[0304] According to the method according to the present invention e.g. seven rod-shaped bodies are inserted into the guide channels from each a spool arranged on an appliance for feeding of rod-shaped bodies through the respective feeding sections and alignment sections of the feeding element.

[0305] The seven rod-shaped bodies are fed through the guide channels in the direction of production through the global sleeve into the extrusion space. In the guide channels or their outlet openings 8, 10, resp., the exact alignment of the rod-shaped bodies occurs.

[0306] Via a laterally arranged polymer feeding appliance a polymer mass is fed into the extrusion space in fluid state.

[0307] The housing is heated by means of a heating appliance in order to maintain the polymer mass in a fluid state.

[0308] The individual rod-shaped bodies are impinged with a melt when released from the ends of the guide channels at the front end in direction of the production. The gaps between the individual rod-shaped bodies are filled with the polymer from the extrusion space, whereby these are embedded in the polymer or agglutinated, resp.

[0309] During the subsequent passage of the rod-shaped bodies through the melt channel of the outlet nozzle an optimal wetting of the rod-shaped bodies with the melt occurs due to the relative movement between the melt and the rod-shaped bodies. Moreover, the arrangement of the rod-shaped bodies relative to each other is stabilized and maintained by the melt channel and its straight alignment relative to the guide channels.

[0310] According to the invention it is intended that the rod-shaped bodies when entering the melt channel 22 are arranged in the region of the indentations 28. Such an arrangement effects that the rod-shaped bodies are sufficiently impinged with polymer in the extrudate and that the rod-shaped bodies do not protrude from the extrudate.

[0311] This means that the protrusions or the grooves 27, resp., are arranged relative to the peripheral guide channels by half their offset angle.

[0312] Accordingly, the peripheral guide channels 9 in the global sleeve 1 are about axially straight aligned relative to the indentations 28 of the melt channel 22. Such an alignment of the peripheral guide channels relative to the indentations effects that the polymer flowing into the indentations 27 during transition from the contoured section towards the round outlet opening 25 in the melt channel 22 is pressed in that region in which the rod-shaped bodies are located, so that these during release from the apparatus are sufficiently covered with polymer and a round extrudate is producible.

[0313] Furthermore by means of this offset a slight pressure is exerted onto the rod-shaped bodies so that these can take the exact geometric arrangement in the structured extrudate.

[0314] However, if the rod-shaped bodies shall be located further outside in the extrudate, it can be provided that the peripheral guide channels 9 of the global sleeve 1 are arranged about in axially straight alignment relative to the indentations or the grooves 27, resp., of the melt channel. Such an alignment of the peripheral guide channels relative to the indentations of the melt channel effects that the polymer flowing into the indentations 28 in the melt channel is pressed into the region between the rod-shaped bodies so that during release from the apparatus a round extrudate can be provided.

[0315] Should the distance between the rod-shaped bodies in the guide channels be larger than the distance they shall have in the structured extrudate, it is provided that the diameter of the melt channel is designed such that the rod-shaped bodies during release from the outlet nozzle are compressed by the melt channel, in particular by the indentations. The compression of the rod-shaped bodies may especially then be necessary when the distance between the individual rod-shaped bodies relative to each other shall be smaller than the summed up distance of the walls of the guide channels.

[0316] It is relevant for this production step that the distance of the ends of the guide channel at the front end in the direction of production till the outlet nozzle is not too long, in particular not longer than 8 mm, as this determines how long the rod-shaped bodies are impinged with the melt.

[0317] During release from the outlet nozzle the final fixation of the geometry of the structured extrudate occurs, which is determined by the diameter of the melt channel and particularly of the outlet opening 25 of the outlet nozzle.

[0318] The guidewire produced in such way subsequently is cooled in a water bath.

[0319] An alignment unit ensures a straight axial alignment of the structured extrudate relative to the melt channel of the outlet nozzle and the guide channels in such a way that these are least influenced by the polymer melt and evenly enclosed by the polymer.

[0320] The passage of the rod-shaped bodies through the extrusion apparatus is realized by means of a belt-type take-off unit. The take-off speed of the belt-type take-off unit determines the speed with which the medical instrument is produced by the extrusion apparatus.

[0321] A structured extrudate may be a medical instrument, such as e.g. a catheter or a guidewire or a semi-finished material for such an instrument, of also elongated micro wires, fibers, such as e.g. sheathed glass fibers, wires, or similar.

[0322] The extrudates producible with the apparatus according to the present invention provide an outer diameter of maximally about 2.5 mm, or 2.3 mm, or 2.0 mm, or 1.8 mm, or 1.6 mm, or 1.3 mm, or 1 mm.

[0323] A cross section through medical instruments 30 which contain the rod-shaped bodies with contoured cross section as disclosed in the description of the advantages is shown in FIGS. 8 to 15. These Figures equally display a cross section perpendicular to the direction of production 3 in a global sleeve 1 according to the present invention in the region of the outlet opening 8 with a central guide channel 6 and peripheral guide channels 9, as well as a medical instrument 30 with a central rod-shaped body 31 and several peripheral rod-shaped bodies 32 which mostly provide a contoured cross section.

[0324] In the following various embodiments of a structured extrudate or a medical instrument 30, resp., with a central rod-shaped body 31 and several peripheral rod-shaped bodies 32 are described. The central rod-shaped body 31 and the several rod-shaped bodies 32 may have contoured cross sections which are three- or four- or multiple-cornered, trapezoid or elliptic or oval or bean-shaped.

[0325] According to a first embodiment a medical instrument 30 comprises a central rod-shaped body 31 with a hexagonal cross section, whereas the edges of the hexagon relative to a plane perpendicular to a longitudinal direction 33 is provided convex (FIG. 8). In the region of the convex edges of the hexagonal central rod-shaped body 31 each an elliptic peripheral rod-shaped body is arranged radially circumferential and equally apart from each other so that in total six peripheral rod-shaped bodies 32 are arranged in the structured extrudate 30.

[0326] According to another embodiment a medical instrument 30 comprises the central rod-shaped body 31 provides a hexagonal cross section with identical edge lengths, whereas in the region of the edges of the hexagon of the central rod-shaped body 31 arranged radially circumferential and equally apart from each other six peripheral rod-shaped bodies 32 with an elliptic cross section are provided (FIG. 9).

[0327] According to another embodiment the central rod-shaped body 31 provides a round cross section, whereas likewise six rod-shaped bodies 32 with elliptic cross section are arranged radially circumferential and equally apart from each (FIG. 10).

[0328] According to another embodiment the central rod-shaped body 31 provides a round cross section, whereas the peripheral rod-shaped bodies 32 provide an about trapezoidal cross section (FIG. 11). The trapezoidal cross section of the peripheral rod-shaped bodies 32 is provided in such a way that the edges of the trapezoid running in radial direction relative to the longitudinal direction 33 are arranged about in parallel to each other and the two edges of the trapezoid running about in parallel to each other are provided in concave shape in vertical direction relative to the longitudinal direction.

[0329] According to another embodiment of the medical instrument 30 it comprises a central rod-shaped body 31 with a pentagonal cross section, whereas the edges of the pentagon are provided in concave shape relative to the longitudinal direction 33 (FIG. 12). Similar to the embodiment as described in FIG. 8 five peripheral rod-shaped bodies 32 are provided, which are arranged in the region of the edges of the central rod-shaped body 31, and whereas an edge formed along the edge of the central rod-shaped body 31 of the peripheral rod-shaped bodies 32 relative to the longitudinal direction 33 may be provided in convex shape (FIG. 12).

[0330] According to another embodiment the central rod-shaped body 31 may be provided as an equilateral polygon, in particular a pentagon. Accordingly, five peripheral rod-shaped bodies with elliptic cross section are provided, the edges of which are provided in concave shape relative to a plane vertical to the direction of production 3 (FIG. 13).

[0331] According to another embodiment of the medical instrument 30 the central rod-shaped body 31 is round, whereas radially circumferential and equally apart from each other five elliptic peripheral rod-shaped bodies 32 are provided, the edges of which are provided in convex shape relative to a plane vertical to the longitudinal direction (FIG. 14).

[0332] According to another embodiment which essentially corresponds to the embodiment as described in FIG. 11 instead of six peripheral rod-shaped bodies 32 also five peripheral rod-shaped bodies 32 with about trapezoidal shape may be provided which are equally apart from each other (FIG. 15).

[0333] A medical instrument 30 according to the present invention comprises usually a central rod-shaped body 31 with a cross section provided round or multi-cornered, whereas the edges of the polygon are provided in convex or concave shape relative to a plane vertical to the longitudinal direction 33.

[0334] Furthermore such a medical instrument 30 comprises at least three, or four, or five, or six, or seven, or eight, or nine, or more peripheral rod-shaped bodies 32 which are shaped elliptic, polygonal, trapezoidal, and whereas their edges relative to the longitudinal direction 33 are concavely or convexly shaped.

LIST OF REFERENCE NUMERALS

[0335] 1 global sleeve [0336] 2 cylindrical section [0337] 3 direction of production [0338] 4 frustum section [0339] 5 step [0340] 6 central guide channel [0341] 7 feeding opening [0342] 8 alignment opening [0343] 9 peripheral guide channel [0344] 10 peripheral alignment opening [0345] 11 peripheral feeding opening [0346] 12 apparatus [0347] 13 lateral wall [0348] 14 nozzle wall [0349] 15 outlet nozzle [0350] 16 fixation [0351] 17 bushing element [0352] 18 transit opening [0353] 19 step [0354] 20 extrusion space [0355] 21 frustum [0356] 22 melt channel [0357] 23 alignment wall [0358] 24 entry opening [0359] 25 outlet opening [0360] 26 frustum [0361] 27 groove/protrusion [0362] 28 indentation [0363] 29 rod-shaped body [0364] 30 structured extrudate/medical instrument [0365] 31 central rod-shaped body [0366] 32 peripheral rod-shaped body [0367] 33 longitudinal direction of the medical instrument or the rod-shaped body