Flexible endoscope based upon an investment composition

Abstract

In the case of an endoscope, it is proposed that an investment composition consisting of a flexible, controllable section be anchored in a counter bearing, which forms a support surface for the respective flexible section.

Claims

1. A flexible endoscope for insertion into the human body, the endoscope comprising: a flexible section arranged in a distal end region of the endoscope; a tip segment distally adjoining the flexible section, said tip segment being controllable by means of at least one tension cord; and wherein the flexible section is formed by means of an investment composition that is mechanically anchored to the tip segment and/or a proximal counter bearing.

2. The flexible endoscope according to claim 1 wherein a carrier body of the tip segment forms a proximal end surface, and the investment composition extends distally beyond the proximal end surface, and/or the proximal counter bearing forms a distal end surface, and the investment composition extends proximally beyond the distal end surface.

3. The flexible endoscope according to claim 1 wherein a carrier body of the tip segment, forms a distal anchoring aid for anchoring the investment composition in the distal tip segment, and/or the proximal counter bearing forms a proximal anchoring aid for anchoring the investment composition in the proximal counter bearing.

4. The flexible endoscope according to claim 3, wherein the distal anchoring aid and/or the proximal anchoring aid are realized by means of a surface treatment, and/or an adhesion agent layer, and/or by interlocking structures such as depressions, gouges, transverse holes, or through-holes.

5. The flexible endoscope according to claim 1, wherein the distal tip segment has at least one optoelectronic, functional element, such as a light source, an image sensor, or another sensor, which is at least partially invested in the investment composition and thus fixed, and the investment composition extends without interruption from the tip segment into the flexible region.

6. The flexible endoscope according to claim 5, wherein light is received and/or emitted by the optoelectronic functional element through the investment composition

7. The flexible endoscope according to claim 1, wherein at least one light source, preferably in the form of an LED, is invested into the investment composition in the region of the tip segment in such a manner that the investment composition acts as an optical fiber and optical diffuser for the light source.

8. The flexible endoscope according to claim 1, wherein the investment composition invests or forms an optical component, such as an optical fiber, in the region of the tip segment.

9. The flexible endoscope according to claim 1, wherein the investment composition forms an optical beam-shaping element for the shaping of a beam of illuminating light that is emitted by the endoscope, out of a micro/nanostructure in the region of the optical beam-shaping element.

10. The flexible endoscope according claim 1, wherein the at least one tension cord has a coating, which preferably prevents the investment composition from adhering, in particular during the injection molding of the investment composition, and/or a plating envelops the at least one tension cord in the region of the flexible section in order to prevent a direct contact of the at least one tension cord with structures outside of the plating.

11. The flexible endoscope according to claim 1, wherein the investment composition is elastically deformable and/or transparent for at least one wavelength that is used for image capturing with the endoscope.

12. A method for producing or assembling a flexible endoscope comprising:— forming a flexible section of the endoscope together with a distal tip segment of the endoscope by means of an investment composition, and wherein the investment composition extends from the flexible section into the tip segment and/or a proximal counter bearing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] FIG. 1 a plan view from above of an endoscope tip of a flexible endoscope according to the invention;

[0049] FIG. 2 a further view of the endoscope from FIG. 1;

[0050] FIG. 3 a further view of the endoscope from FIG. 1;

[0051] FIG. 4 a further view of the endoscope from FIG. 1;

[0052] FIG. 5 a further view of the endoscope from FIG. 1;

[0053] FIG. 6 a further view of the endoscope from FIG. 1;

[0054] FIG. 7 a further view of the endoscope from FIG. 1 with a fully stretched flexible section and a detailed view of the distal tip segment of the endoscope;

[0055] FIG. 8 a further view of the endoscope from FIG. 7;

[0056] FIG. 9 a further view of the endoscope from FIG. 7, with a enveloping tube removed so that the view of the skeleton below is clear;

[0057] FIG. 10a side view of the endoscope from FIG. 7;

[0058] FIG. 11a further side view of the endoscope from FIG. 7,

[0059] FIG. 12 to FIG. 17 various possible configurations of the tip segment of the endoscope;

[0060] FIG. 18 a partial longitudinal section through the endoscope according to FIG. 1;

[0061] FIG. 19 a detailed view B of the longitudinal section from FIG. 18;

[0062] FIG. 20 a single guide element of the skeleton of the endoscope from FIG. 18;

[0063] FIG. 21 another view of the endoscope from FIG. 18, this time only with the enveloping tube removed, so that the view of the investment composition underneath, which partially envelops the skeleton, is clear;

[0064] FIG. 22 a detailed view of the view according to FIG. 21, viewed from above;

[0065] FIG. 23 the endoscope from FIG. 21 in the same view but with an angled flexible section;

[0066] FIG. 24a further endoscope according to the invention in a partial longitudinal sectional view;

[0067] FIG. 25a detail A of the view from FIG. 24;

[0068] FIG. 26a further detailed view of the endoscope from FIG. 24;

[0069] FIG. 27a single guide element of the skeleton of the endoscope from FIGS. 24 and 26, which is designed in such a way that tension cords can be inserted laterally from above into tension guides of the guide element;

[0070] FIG. 28a further endoscope according to the invention in a partial longitudinal sectional view;

[0071] FIG. 29a detail A of the view from FIG. 28;

[0072] FIG. 30a further detailed view of the endoscope from FIG. 28;

[0073] FIG. 31a single guide element of the skeleton of the endoscope from FIGS. 28 and 30, which is designed in such a way that tension cords can be introduced into tension guides of the guide element along a longitudinal axis of the endoscope;

[0074] FIG. 32 to FIG. 40 various designs of guide elements, wherein various types of holding devices for the tension cords are shown;

[0075] FIG. 41a longitudinal section through the flexible section of an endoscope according to the invention and its anchoring in a proximal counter bearing;

[0076] FIG. 42 another possible manner of anchoring a flexible section of an endoscope according to the invention in a proximal counter bearing;

[0077] FIG. 43 another possible manner of anchoring a flexible section of an endoscope according to the invention in a proximal counter bearing;

[0078] FIG. 44a skeleton of an endoscope according to the invention with two tension cords, designed for a 2-fold angulation, before investment in an investment composition;

[0079] FIG. 45a detailed view of the skeleton from FIG. 44;

[0080] FIG. 46a skeleton of an endoscope according to the invention with four tension cords, designed for 4-fold angulation, before investment in an investment composition;

[0081] FIG. 47a detailed view of the skeleton from FIG. 46;

[0082] FIG. 48a skeleton of an endoscope according to the invention with a number of more than four tension cords, designed for multiple angulation, before investment in an investment composition;

[0083] FIG. 49a detailed view of the skeleton from FIG. 48;

[0084] FIG. 50 an illustration of possible angulations of the endoscope from FIG. 46;

[0085] FIG. 51a further illustration of possible angulations of the endoscope from FIG. 46;

[0086] FIG. 52 an example of an exoskeleton according to the invention for an endoscope according to the invention;

[0087] FIG. 53a view from above of the exoskeleton of FIG. 52;

[0088] FIG. 54 an example of an endoskeleton according to the invention for an endoscope according to the invention, wherein the skeleton has an axial support structure;

[0089] FIG. 55a view from above of the endoskeleton of FIG. 54;

[0090] FIG. 56a further example of a skeleton of an endoscope according to the invention;

[0091] FIG. 57a detailed view of the skeleton from FIG. 56;

[0092] FIG. 58a longitudinal sectional view of the skeleton from FIG. 56; and

[0093] FIG. 59a detailed view of the longitudinal section from FIG. 58 showing the axial fixing of the guide elements on the axial support structure.

DETAILED DESCRIPTION

[0094] In the following description of various preferred embodiments of the invention, elements with corresponding functions are given the same reference numbers, even if they have a different design or shape. The figures are therefore initially described together, and the differences between the exemplary embodiments are discussed below. The explanations then apply accordingly.

[0095] As used herein, the terms “invest,” “investing,” and “invested,” refer to embedding, molding, or otherwise surrounding/containing a component or structure within a material, such as, for example, a component of a flexible endoscope within another component or structure of the endoscope.

[0096] The term “investment composition” as used herein refers to a soft, flexible material into which other components or structures may be invested, e.g., molded, embedded or otherwise surrounded by/contained within the material. The investment composition may be a polymer such as silicone, into which, for example, a skeleton 6 of an embodiment, may be molded/embedded, either by injection molding, by a casting process, or by other techniques, such as, for example, processes where the investment composition is initially a liquid and then is solidified into a mass, via UV curing, a curing agent, and the like. As described in greater detail herein, the investment composition may be a single material such as a temperature-curing, one-component silicone, or a multiple component composition such as a two-component epoxy or silicone.

[0097] The figures each show the endoscope tip, that is to say a distal end region 3 of a flexible endoscope 1 or parts thereof. The various endoscopes 1 shown are designed to be inserted into the human body or into another cavity (for non-medical applications).

[0098] For this purpose, the endoscopes have a flexible section 2, which is arranged in a distal end region 3 of the endoscope 1.

[0099] A distal tip segment 4 adjoins the flexible section 2.

[0100] The tip segment 4 can be controlled in a manner known per se by means of at least one tension cord 8.

[0101] In the embodiments according to the invention, the flexible section 2 has a skeleton 6, which has a large number of guide elements 7. These guide elements 7 guide the tension cords 8 in such a way that their position is fixed transversely to the longitudinal direction of the endoscope 1, that is to say radially, and in the circumferential direction.

[0102] For this purpose, the respective tension guides 9 of the guide elements 7 each define a radial position 11 and/or an angular position 12 of the at least one tension cord 8.

[0103] Here, the radial position 11 and/or the angular position 12 can be defined in relation to a neutral fiber 13 of the flexible section 2.

[0104] The guide elements 7 are lined up, preferably at regular intervals, along the neutral fiber 13, which can define a longitudinal direction of the endoscope 1. However, the distances can also be of different sizes, depending on the configuration.

[0105] For simple production, it is preferable for the guide elements 7, as illustrated in the figures, to be designed in order to be identical to one another. However, particularly in the case of endoscopes that allow multiple angulations, it can be useful to assemble guide elements 7 that are not identical, that is, differently configured, in order to form a skeleton 6.

[0106] The skeleton 6 (e.g. in FIG. 18) is designed as an inner skeleton (i.e. it is not part of an outer shell) and has an axial support structure 10, which is used in order to axially fix the guide elements 7 along a longitudinal axis 16 of the flexible section 2.

[0107] The axial support structure 10 has (at least) one support tube 17 with (at least one) internal working volume 18 or (at least one) working channel 35 and forms a flexible core, which—without a working volume—can be designed free of cavities. The working channel 35 can form a receptacle 37 for instruments.

[0108] FIG. 17 shows a variant with an additional flushing and/or instrument channel 36. The latter can also be integrated into the working channel 35.

[0109] The skeleton 6 is invested into an investment composition 14. This investment composition 14 also forms the flexible section 2 and defines its mobility or flexibility.

[0110] In this case, the investment composition 14 fills the interstices 15 between the guide elements 7 at least partially or even completely. The guide elements 7 are thus supported against one another.

[0111] The investment composition 14 is vacuum-cast (that is, cast using a negative pressure) or cast in some other way in the interstices of the skeleton 6.

[0112] The axial support structure 10 can also be cast, for example with the aid of a first component of a two-component investment composition. This first component can preferably (in the hardened state) be more rigid than a second component of the two-component investment composition. The latter can then form the investment composition 14 described above. As a result, sufficient mechanical stability is achieved by the first component, with simultaneous high flexibility due to the softer second component.

[0113] It can be seen from the figures that the guide elements 7 are each designed in the form of discs. The guide elements 7 are designed to be rigid and can stably absorb lateral forces that act on the tension cords 8 when subjected to tension stress.

[0114] As can be seen for example in FIG. 19 or FIG. 54, it is advantageous for a high mechanical stability of the skeleton 6 when guide elements 7a, 7b, which are directly adjacent to one another, are at most as far apart from one another as their respective diameter.

[0115] For this purpose, the guide elements 7 lie transversely to a running direction 19 of the at least one tension cord 8, so that the respective tension cord 8 runs transversely through the guide element 7.

[0116] The guide elements 7 are thus aligned with a longitudinal axis 16 of the endoscope 1.

[0117] It can also be seen from the figures that the guide elements 7 are arranged within the flexible section 2 in order to stabilize it. Here, a distance between directly adjacent guide elements 7a, 7b is less than their respective diameter.

[0118] The flexible section 2 is controlled in a manner known per se by tensile and/or compressive stress on the tension cords 8. For this purpose, due to the current shape of the flexible section 2, each tension cord 8 develops lateral forces which can be directed radially inwards or outwards. The guide elements 7 thus each support forces applied radially inwards and/or radially outwards from the tension cords 8 and thus prevent the tension cords 8 from cutting into the investment composition 14 when the tip segment 4 is actuated.

[0119] Here, the guide elements 7 do not support the respective tension cord 8 at least at a respective insertion point 20.

[0120] Furthermore, the guide elements 7 each form passages 21 for the tension cords 8. The tension cords 8 can thus be introduced from the outside transversely to their respective running direction 19. A threading is therefore not necessary.

[0121] In order to absorb the radial forces mentioned, the passages 21 each have support surfaces 22 arranged radially on the outside.

[0122] It can be seen that the guide elements 7 are shaped in such a way that the tension cords 8 can each be inserted or hooked into tension guides 9 of the guide elements 7 transversely to a longitudinal axis 16 of the endoscope 1.

[0123] For this purpose, a holding device 23 is formed on each of the tension guides 9 in order to prevent the tension cord 8 from escaping from the tension guide 9.

[0124] The securing device 23 has a clamping or crimping mechanism (crimping 27), wherein the guide elements 7 are elastically or plastically deformable in the region of the cable guides 9 in order to form the holding device 23.

[0125] Between the guide elements 7, there are sections 24 which are not covered by the investment composition 14 (cf. FIGS. 21-23 and 41-43). This reduces friction losses between the at least one tension cord 8 and the investment composition 14 when the tip segment 4 is controlled. The exposed sections 24 thus serve to keep the control forces for the angulation of the tip segment as low as possible and thus enable a particularly smooth angulation.

[0126] The flexible section 2 has a plurality of at least partially circumferential indentations 46, which are formed by casting/injection molding the investment composition 14, wherein the indentations 46 follow circular paths or helical lines.

[0127] FIGS. 1 to 45 and 50 to 59 show exemplary embodiments with two tension cords 8, 8a, 8b.

[0128] FIGS. 46, 47 show an exemplary embodiment with four tension cords 8a, 8b, 8c, 8d, and FIGS. 48 and 49 show an embodiment example with a large number of tension cords 8.

[0129] In FIGS. 48 and 49, it can be provided that the tension cords 8 do not all begin or end at the same axial height, for example for a control with multiple different or opposing successive curvatures.

[0130] Each of the guide elements guides all existing tension cords 8, 8a, 8b, 8c, 8d, wherein the tension cords 8, 8a, 8b, 8c, 8d are each connected to the distal tip segment 4 of the endoscope 1 and to individual guide elements 7 in a tension-resistant manner.

[0131] A possible production or assembly of a flexible endoscope 1 is described below.

[0132] For this purpose, a large number of guide elements 7 for guiding at least one tension cord 8 of the endoscope 1 are lined up in order to form a skeleton 6, even before the skeleton 6 is invested into an investment composition 14.

[0133] The guide elements 7 are aligned and held in position during investment in the investment composition 14 by an investment mold that is used for this purpose. Before the skeleton 6 is invested in the investment composition 14, each tension cord 8, 8a, 8b, 8c, 8d is introduced into tension guides 9 of the guide elements 7 along a longitudinal axis 16 of the endoscope 1. Alternatively, it is also possible to insert each tension cord 8, 8a, 8b, 8c, 8d laterally in tension guides 9 of the guide elements 7 transversely to a longitudinal axis 16 of the endoscope 1.

[0134] There, it is held in position by means of holding devices 23 formed on the guide elements 7.

[0135] The tension cords 8, 8a, 8b, 8c, 8d are then each invested in an inserted position of the investment composition 14.

[0136] The guide elements 7 are thus lined up in order to form the skeleton 6 by being threaded onto tension cords 8, 8a, 8b, 8c or onto an axial support structure 10.

[0137] In FIGS. 12 to 17, a great variety of combinations are shown. For example, lighting and sensor components can be arranged as desired within an encapsulation material. Image sensors 31 can be used as sensors, for example, and/or sensors 34 for pH value, pressure, temperature, magnetic field and/or position in space, in each case with any required reference sensors.

[0138] The lighting can be realized, for example, by means of an LED 32, which is arranged either in the tip segment 4 or—if necessary, with lateral irradiation for homogeneous illumination—in the investment composition 14, for example in transparent silicone.

[0139] Optical fibers 33, for example glass and/or plastic fibers, can be present with proximal illumination by an LED or a laser—also multispectrally with several wavelengths, for example.

[0140] For the lighting, a nanostructure and/or microstructure and/or a recess for molding a lens can also be provided in a casting mold, in particular the casting mold for the skeleton 6. The latter can optimize the illumination and/or project a light grid—for example for structured light measurements or strip light topometry.

[0141] FIG. 23 shows an angled silicone volume with free-standing cables or tension cords 8, which are guided and stabilized by the guide elements 7 in the form of insert rings or ribs.

[0142] The silicone composition or investment composition 14 acts between the guide elements 7 as an intervertebral disc. The combination of incised edge structures realized by the casting mold, free-standing tension cords 8, and guide elements 7 enables the smallest possible angulation radii or bending radii 38.

[0143] In further exemplary embodiments, instead of or in addition to the proximal anchoring aids or interlocking structures 43, gouged anchoring or interlocking structures are also embodied on the tip segment 4, or at least distally so.

[0144] In FIGS. 41 to 43, for example, different gouges can be seen, into which the investment composition 14 can penetrate in order to anchor the flexible section 2.

[0145] FIG. 52 shows an embodiment with a skeleton 6, which is designed as an exoskeleton.

[0146] FIGS. 56 to 59 show a variant in which the guide elements 7 are mounted on a tube structure, for example an elastomer, as individual segments, wherein the guide elements 7 do not touch each other but are held in position by gouges or grooves on the tube structure. These gouges or grooves thus form axial fixings 48 for the guide elements 7.

[0147] The interior of the tube structure can be used for the passing of lines and lighting fibers and for flushing or for tools/instruments.

[0148] The figures further show that the flexible section 2 is formed by means of an investment composition 14 and that the investment composition 14 is mechanically anchored in the tip segment 4 and a proximal counter bearing 25. The uncontrolled section of the endoscope 1, which is covered by a stabilization tube 45 or a flexible enveloping tube 47, adjoins the counter bearing 25 proximally.

[0149] Here, the distal tip segment 4 forms a distal counter bearing 26. For this purpose, the tip segment can have a carrier body 50, for example an injection-molded one, as illustrated in FIGS. 44 and 45, which can form distal anchoring aids 41 for anchoring the investment composition 14 and can also carry optical or electronic components such as light sources or sensors. Furthermore, tension cords 8 can also be anchored in the carrier body 50. In addition to the carrier body 50, the distal tip segment can thus comprise electronic and/or optoelectronic components as well as parts of the investment composition 14. Because the distal counter bearing 26 is enclosed by the investment composition 14, it cannot be seen in FIGS. 1 to 6, 10, 11, and 21 to 23.

[0150] On the distal tip segment 4, more precisely on the carrier body 50, a proximal end surface 39 is also formed, upon which the flexible section 4 is supported.

[0151] The investment composition 14 extends distally beyond the proximal end surface 39. The investment composition 14 thus extends on both sides of the end surface 39.

[0152] In the same way, the proximal counter bearing 25 forms a distal end surface 40 upon which the flexible section 4 is supported with its other end.

[0153] The flexible section is thus clamped between the end surfaces 39, 40, wherein there exists a tensile stress due to the tension cords 8.

[0154] Here, too, the investment composition 14 extends proximally beyond the distal end surface 40 and thus extends on both sides of the end surface 40.

[0155] The tip segment 4, more precisely its carrier body 50, forms a distal anchoring aid 41 for anchoring the investment composition 14 in the distal tip segment 4.

[0156] The proximal counter bearing 25 also forms a proximal anchoring aid 42 for anchoring the investment composition 14 in the proximal counter bearing 25.

[0157] Both the distal anchoring aid 41 and the proximal anchoring aid 42 are implemented in different embodiments by means of a surface treatment and/or by means of an adhesion agent layer and/or by means of interlocking structures 43, such as depressions, gouges, transverse holes, or through-holes.

[0158] The distal tip segment 4 also has at least one electronic, in particular optoelectronic, functional element 44, for example a light source 32, 33, an image sensor 31, or some other sensor 34. Signal lines 30 can also be formed to and/or from the functional element 44.

[0159] The functional element(s) 44 is/are invested in the investment composition 14 and is/are thus fixed. For this purpose, the investment composition 14 extends without interruption from the tip segment 4 into the flexible region 2.

[0160] The investment composition 14 is designed to be transparent or translucent. Thus, light can be received and/or emitted by the electronic functional element 44 through the investment composition 14.

[0161] At least one light source, preferably in the form of an LED 32, is invested in the investment composition 14 in the region of the tip segment 4 in such a way that the investment composition 14 serves as an optical fiber and optical diffuser for the light source.

[0162] The investment composition 14 invests an optical component, such as an optical fiber 33, in the region of the tip segment 4, or it forms such an optical component.

[0163] The investment composition 14 can, for example, form an optical beam-shaping element for shaping beams of illuminating light. The endoscope 1 can thus emit this illuminating light (if necessary, via illuminating optics 29), wherein the investment composition 14 is formed for this purpose by a micro/nanostructure in the region of the optical beam-shaping element.

[0164] The tension cords 8, 8a, 8b, 8c, 8d each have a coating that prevents the investment composition 14 from adhering or enables it to be torn away in a controlled manner when used for the first time.

[0165] Alternatively, a plating 49 can envelop each tension cord 8, 8a, 8b, 8c, 8d in the region of the flexible section 2 in order to prevent a direct contact of the at least one tension cord 8, 8a, 8b, 8c, 8d with structures outside of the plating 49.

[0166] The investment composition 14 is generally elastically deformable and—as mentioned above—transparent for at least one wavelength used for image capturing (possibly via image capturing optics 28) with the endoscope 1 and/or for a wavelength that is emitted as illuminating light by the endoscope.

[0167] In a method for producing or assembling one of the flexible endoscopes 1, a flexible section 2 of the endoscope 1 is formed together with a distal tip segment 4 of the endoscope 1 by means of an investment composition 14.

[0168] This is done in such a way that, after it has been introduced, the investment composition 14 extends from the flexible section 2 into the tip segment 4 and into a proximal counter bearing 25. The investment composition 14 thus structurally provides a tensile connection between the proximal counter bearing 25 and the distal counter bearing 26 in the tip segment 4.

[0169] According to the invention, it is proposed, in the case of an endoscope 1, that an investment composition 14 consisting of a flexible, controllable section 2 be anchored in a counter bearing 25, 26, which forms a support surface 51 for the respective flexible section 2. It is further proposed that a skeleton 6 be formed in a flexible, controllable section 2 with guide elements 7 that are movable relative to one another, each of which guides at least one tension cord 8, 8a, 8b, 8c, 8d laterally. Here, the aforementioned investment composition can support the guide elements 7 of the skeleton 6 against one another.