DE102020118048A1 - Deflection control mechanism for a steerable flexible endoscope, steerable flexible endoscope, endoscope mounting kit and method of mounting a flexible endoscope - Google Patents

Abstract

The invention relates to a deflection control mechanism (29) for a steerable flexible endoscope (10), the endoscope (10) having an elongate flexible shaft (30) comprising a steerable section (31) which, by movement of at least one pair counteracting control wires (37, 37', 38, 38'), the deflection control mechanism (29) comprising a support structure, a drive wheel rotationally supported in or on the support structure, and an elongate traction member having a flexible portion, a a first coupling portion connected to a first end of the flexible portion and a second coupling portion connected to a second end of the flexible portion, the flexible portion of the tension member engaging the drive wheel, the first and second Coupling portion each having a fastener for attaching a respective proximal end of each wire of the at least one pair control wires (37, 37', 38, 38'), wherein the first and/or the second coupling section comprises a movable stop element which cooperates with a fixed stop of the support structure, and wherein the support structure comprises at least one base plate which is substantially in a base plane extending at least approximately perpendicular to an axis of rotation of the drive wheel, with the base plate supporting the fixed fence. The invention also relates to a steerable flexible endoscope (10), an endoscope assembly set and a method for assembling a flexible endoscope (10).

Description

The present invention relates to a deflection control mechanism for a steerable flexible endoscope, a steerable flexible endoscope having such a deflection control mechanism, an endoscope assembly kit and a method of assembling a flexible endoscope.

Flexible endoscopes include a flexible, elongate shaft that is configured to be inserted into an internal cavity of the body of a human or animal, or any other object. Imaging optics for generating an image of a scene in the cavity under consideration are arranged in a distal (i.e. user-remote) end portion of the shaft. The endoscope image produced can be transmitted by a fiber optic bundle to a proximal (i.e., user-proximate) end of the shaft to be captured by an electronic image sensor positioned in a handpiece located at the proximal end of the shaft, or an electronic The image sensor can be arranged in the distal end section of the shaft, with the image signal being transmitted by electrical lines arranged in the shaft. A flexible endoscope typically includes an illumination system for illuminating the cavity to be viewed, and one or more instruments and/or fluid conduits extending from the handpiece through the shaft to its distal end.

Flexible endoscopes are typically used to view a cavity that is accessed via a curved path, or to view the interior of an organ that is itself curved in shape, such as the intestine. Because of its flexibility, the flexible shaft is able to conform to the curvature of the access pathway or organ during insertion. However, it is often desirable to be able to actively deflect or bend the distal end portion of the flexible shaft from a straight orientation to a curved or articulated shape to facilitate insertion over a curved access pathway or organ. Since a viewing direction of the imaging optics is generally determined by a direction of the distal end section of the endoscope shaft, active deflection of the distal end section also allows a desired partial area of the cavity to be viewed, and an essentially complete view of the surface of the Cavity may be allowed by varying a deflection angle of the distal end portion. Endoscopes that allow a portion of the flexible shaft to be actively deflected or flexed are commonly referred to as "steerable endoscopes".

A steerable or deflectable portion of the shaft of a steerable endoscope usually has a support structure of, for example, sequentially articulated pivoting members, which pivoting members can be tilted toward one another by axially moveable control wires. As an alternative, the supporting structure can be formed, for example, by one or more elastic bending elements which can be bent by the action of control wires. The support structure is enclosed, for example, by a flexible sleeve made of a plastic material. Deflection of the steerable portion from an aligned position to a curved or articulated configuration in one or an opposite direction can be controlled by reciprocating movement of a pair of opposing control wires. Steerable endoscopes allow the steerable section to be bent in two perpendicular planes, often through the operation of two pairs of steering wires. The control wires may be routed along the outside or inside of the pivot members and extend through the shaft in a proximal direction into the handpiece where a deflection control mechanism is provided. The deflection control mechanism causes movement of the control wires under user control, for example by turning one or more handwheels.

Due to the design of the pivoting elements or the elastic bending elements and/or due to requirements that the flexible sheath or other elements of the shaft have a minimum bending radius, the articulation of the steerable section is limited to a maximum permissible deflection angle. However, during operation of the steerable endoscope, a user typically does not have direct visual control over the articulation of the steerable section. Therefore, steerable endoscopes have been provided with a deflection control mechanism that includes a mechanical stop to avoid exceeding the maximum allowable deflection angle and thus to avoid components being broken or unduly deformed.

Flexible steerable endoscopes are available with a wide variety of shaft lengths, shaft diameters, internal configurations with instrument and/or irrigation channels, and shaft rigidities, as well as lengths, diameters, configurations, rigidities, and maximum deflection angles of the steerable section. In any event, the longitudinal movement of the control wires may be limited to a specific range corresponding to a specific maximum deflection angle. On the other hand, for reasons of cost, it would be desirable Use standard components for a variety of endoscopes.

From the EP 2 835 096 B1 a bending angle adjusting mechanism for adjusting a maximum bending angle of an endoscope is known. The mechanism is for adjusting a moving amount and a moving range of bending operation wires and chains in a bending operation mechanism for performing a bending operation of a bending portion of the endoscope. The bending angle adjusting mechanism includes a stopper member that restricts movement of the bending operation wire, and a screw member that makes positional adjustment by moving a position of the stopper member along a moving direction of the operation wire.

According to the European patent application EP 3 222 195 A1 For example, an endoscope has a bending adjustment unit that includes a stopper portion and a contact part that comes into contact with the stopper portion, thereby regulating movement of a chain to which bending wires are coupled. A bending operation mechanism and the bending displacement unit are provided on a flat surface side of a main frame formed in a plate shape. Further, there is provided a chain cover formed in a plate shape, and a cover member formed by a third plate member is disposed on an end face of an upright second chain case wall.

It has been found that the known deflection control mechanisms of steerable flexible endoscopes are not optimal in terms of assembly and maintenance. In particular, each type or size of endoscope requires a specific, high-level assembly that includes a mechanical stop assembly that is matched to the allowable range of deflection angles for that particular type or size of endoscope, thereby introducing additional inventory and manufacturing planning issues. Also, with known deflection control mechanisms, haptic feedback to a user is often insufficient such that the user does not clearly feel when a maximum allowable deflection angle has been reached and may feel that increasing the force applied to a hand wheel of the deflection control mechanism results in a further increase in the bending angle. This can lead to failure of the endoscope.

It is therefore an object of the present invention to provide a deflection control mechanism for a steerable flexible endoscope in which one or more of the above disadvantages are avoided or mitigated. In particular, an object of the invention is to provide a deflection control mechanism which is improved in terms of assembly and/or maintenance and/or has a more clearly defined and stiffer stop. Further objects of the invention are to provide a steerable flexible endoscope with an improved deflection control mechanism, a corresponding endoscope assembly kit and an improved method of assembling a flexible endoscope.

These objects are achieved by a deflection control mechanism according to claim 1, by a steerable flexible endoscope according to claim 13, by an endoscope assembly kit according to claim 14 and by a method according to claim 15. Particular embodiments of the present invention are given in the dependent claims.

The present invention relates to medical endoscopes, i. H. to endoscopes designed for medical applications such as minimally invasive surgery and/or medical examinations. A user of the endoscope is therefore usually a surgeon who performs an endoscopic procedure. However, the present invention also relates to endoscopes that are designed for non-medical purposes, for example industrial endoscopes or boroscopes.

According to one aspect of the present invention, a deflection control mechanism is configured to control a deflection or articulation or a bending angle of a steerable portion of a shaft of a steerable flexible endoscope. The shaft of the endoscope is an elongate, flexible shaft designed to be inserted into an internal cavity of a human or animal body or other object, such as a technical object, and includes a steerable portion that is operable with respect to other portions of the shaft can be actively bent or deflected. In particular, the steerable portion may be actively deflectable under user control with respect to an adjacent portion of the flexible shaft. For example, the steerable portion may form a distal end portion of the shaft or a portion near the distal end of the shaft. The steerable section can comprise imaging optics or imaging optics can be arranged in an end cap arranged at a distal end of the steerable section, so that a viewing direction of the imaging optics can be changed by deflecting the steerable section. The endoscope may further include a handpiece connected to a proximal end portion of the shaft, the handpiece having controls for controlling various functions of the endoscope. An endoscopic image generated by the imaging optics can be transmitted to the handpiece via optical or electronic means. The deflection control mechanism is connectable to the proximal end portion of the shaft and may be housed in the handpiece.

The steerable portion of the flexible endoscope shaft is deflectable by longitudinal movement of at least one pair of opposing steering wires. The steerable portion may have a support structure of, for example, pivoting or elastic elements that can be angled or bent due to a longitudinal force or bending moment exerted by the steering wires. Typically, the two wires of the pair of opposing control wires are located on opposite sides of the support structure, preferably approximately symmetrically about a longitudinal axis of a respective portion of the shaft. In order to control the deflection or bending of the steerable portion, the control wires are movable substantially in their respective longitudinal direction with respect to the shank, this direction usually being parallel to the axial direction of the respective part of the shank. Thus, when a first of the two wires of the pair is pulled to one side in the proximal direction for deflection, the other moves in the distal direction; to deflect to the opposite side, the other of the two wires is pulled in the proximal direction while the first moves in the distal direction. Deflection of the steerable portion from an aligned position to a curved or articulated shape in one or an opposite direction or vice versa can be controlled by such opposite or counteracting movement of the two wires of the pair of control wires. The control wires are routed within the shaft to the proximal end of the shaft thereby being operable in an opposing or counteracting manner such that the deflection control mechanism is connectable to the proximal end of the shaft. The control wires can be connected with reference to a pulling action of the wires, i. H. a force directed in a proximal direction, also referred to as pull wires, or as push-pull wires if the wires are designed similar to Bowden cables in order to also exert a force in a distal direction.

The deflection control mechanism includes a support structure, a drive wheel rotatably supported in or on the support structure, and an elongate traction member. The drive wheel is rotationally supported with, for example, one or more bearings in or on the support structure and has a rotatable axle or shaft or an axle fixed to the support structure. The support structure is preferably rigid. The support structure may include, for example, a non-rotating axle of the drive wheel, a cage structure housing the drive wheel, and/or elements of a housing of the handpiece. The pulling element comprises a flexible section and a first and a second coupling section. The flexible section can be configured as a chain, for example. The flexible portion has a first end and a second end opposite the first end. The first coupling portion is connected to the first end and the second coupling portion is connected to the second end of the flexible portion. The flexible portion and the first and second coupling portions preferably have high rigidity in a longitudinal direction.

Specifically, the flexible portion of the tension member engages the drive wheel with a peripheral surface of the drive wheel so that the first and second coupling portions are longitudinally moved by rotating the drive wheel. The drive wheel may be configured as a sprocket and the flexible portion as a chain, with the teeth of the sprocket engaging the chain segments to move the chain longitudinally. The flexible portion is preferably wrapped around the drive wheel and encloses an angle of about 180° or an angle of about 180° plus an integer multiple of 360° such that the tension member is arranged in an approximate U-shape, or an angle greater than 180°, for example an angle between 180° and 200° or 220°, in order to improve the coupling with the drive wheel while providing a compact design. Both coupling sections can be at least approximately parallel to one another and can define a common longitudinal direction. Therefore, by rotating the drive wheel, the coupling portions are oppositely moved in the longitudinal direction. For example, the drive wheel may be coupled to a handwheel to be rotated manually by the user. Alternatively or additionally, the drive wheel may be coupled or configured to be coupled to a motor to be rotated under motor or robotic control. The flexible endoscope can thus be configured, for example, to be arranged on a robotic arm so that the deflection control mechanism for controlling the articulation of the steerable section can be actuated under robotic control.

The first and second coupling portions are configured to be coupled with the at least one pair of opposing control wires. For this purpose, the first and the second coupling section each comprise a fastening element for fastening a respective proximal end each wire of the at least one pair of opposing control wires. The fastener may be configured, for example, as a rectangular fastener block that includes a longitudinal bore into which the proximal end portion of the respective control wire may be clamped, or into which a clamping member or ferrule holding the wire may be secured. When the deflection control mechanism is connected to the shaft of the steerable endoscope, both wires are secured in their respective fasteners. Thus, by turning the drive wheel, the deflection angle of the steerable section of the shaft can be controlled.

Furthermore, the first and/or the second coupling section comprise a movable stop element which cooperates with a fixed stop of the support structure in order to limit a range of movement of the respective coupling section and thus limit a range of longitudinal movement of the respective control wire. Since the movable stop member consists of the respective coupling portion, it moves together with the respective attachment member and with the respective control wire attached to the attachment member during operation of the deflection control mechanism. The fixed stop is formed or supported by the support structure and therefore remains in a fixed position during operation. The moveable stop member cooperates with the fixed stop to define a limit on movement of the tension member and thus limit movement of the control wires. In particular, the movable stop element can be stopped by contacting the fixed stop when the end of a permissible range of movement of the control wires has been reached. In this way, the deflection of the steerable portion is limited to a maximum deflection or articulation angle at least on one side of the shaft. The first and second coupling sections preferably each comprise a movable stop element which cooperates with a respective fixed stop of the support structure in order to limit a range of movement of the respective coupling section and thus limit a range of movement of the control wires in both the proximal and distal directions. In this way, the deflection of the steerable section can be limited to a maximum deflection angle both on one side and on an opposite side of the shaft.

According to this aspect of the invention, the support structure comprises at least one base plate arranged essentially in a base plane, with the base plane extending at least approximately perpendicularly to an axis of rotation of the drive wheel. The base plate can be substantially planar, have protrusions and/or bores and/or cutouts, and in the longitudinal direction, e.g. H. parallel to the direction of movement of the coupling sections, have a greater extent than in a transverse direction. The base plate can be designed in one piece.

In accordance with this aspect of the invention, the base plate also supports the fixed stop of the support structure. The fixed stop may be an element connected to the base plate, or the fixed stop may be formed by a projection or shoulder of the base plate and thus integral with the base plate. In particular, the fixed stop is located on a side of the base plate that faces the first and/or the second coupling section that includes the movable stop element. Furthermore, the fixed stop is preferably located in the vicinity of the impeller and may be rigidly connected to an axle of the impeller or to a cage structure housing the impeller. Most preferably, the first and second coupling portions each comprise a moveable stop member cooperating with a respective fixed stop of the support structure, with the base plate supporting both fixed stops.

The deflection control mechanism may include other elements such as a brake. A brake allows one or both of the at least one pair of opposing control wires to be locked in their respective longitudinal positions so that the steerable portion of the endoscope is held firmly at an appropriate deflection angle. The deflection control mechanism may include a tensioning mechanism for pretensioning the at least one pair of control wires, the tensioning mechanism being included, for example, in the first and/or second coupling portion. The deflection control mechanism may be configured to effect movement of more than one pair of opposing control wires. The deflection control mechanism is preferably manually operable by turning one or more handwheels and/or may be operable under motor or robotic control. A shaft coupler may be provided on a distal side of the handpiece or the deflection control mechanism to couple the endoscope shaft to the handpiece and/or the deflection control mechanism.

Due to the fact that the support structure is arranged at least one at least approximately perpendicular to an axis of rotation of the drive wheel includes a base plate, the base plate supporting the fixed stop of the support structure in order to interact with the movable stop element of the pulling element, a particularly simple, compact and rigid design can be provided. Thus, the mechanical stop that limits the range of deflection angles can be defined more rigidly so that a user manipulating the steerable endoscope can receive clearer haptic feedback when a maximum deflection angle has been reached. In particular, a handwheel manually rotated by the user to operate the deflection control mechanism cannot appreciably continue to be rotated once the limit is reached, even if increased torque is applied to the handwheel. This can facilitate the operation of the deflection control mechanism. Furthermore, due to increased rigidity, breakage of components during operation can be avoided more securely.

Depending on a particular intended application, steerable endoscopes have different shaft diameters, different shaft lengths, different maximum deflection angles, and/or they may differ in other properties and therefore have different allowable ranges of longitudinal movement of the steering wires. The longitudinal positions of one or both fixed stops in relation to the respective movable stop element are preferably determined in such a way that a permissible maximum deflection angle of a specific endoscope shaft cannot be exceeded. Because the base plate supports one or both of the fixed stops of the support structure, the deflection control mechanism can be tailored to a specific endoscope shaft style or size with a specific range of motion of the control wires by appropriately machining or selecting the base plate while all other elements of the Deflection control mechanism can be suitable for different shaft types or sizes, since they are standardized in this sense. Furthermore, the deflection control mechanism can be adapted to a different endoscope shaft type or size by changing only the base plate, while all other elements remain unchanged. In this way, manufacturing inventory and planning expenses can be reduced.

The movable stop element of the first and/or second coupling section is preferably adjustably connected to the fastening element of the respective coupling section. In particular, a longitudinal position of the movable stop element with respect to the fastening element can be adjusted, for example, in that the movable stop element is mounted on a threaded rod which extends essentially in the longitudinal direction of the respective coupling section and is connected to the fastening element of the respective coupling section, the movable stop element can be adjusted by turning or screwing it on the threaded rod in the proximal or distal direction. In particular, the deflection control mechanism is designed so that the relative position of the movable stop member can be adjusted during assembly or maintenance. On the other hand, the fixed stop generally has a position predetermined by the design of the base plate and is therefore not adjustable. Due to the interaction of the movable stop element with the fixed stop, a movement limit of the respective control wire can be adjusted in this way, at least in the proximal or the distal direction. Most preferably, the first and second coupling sections each comprise a movable stop member cooperating with a respective fixed stop of the support structure, and both movable stop members are adjustably connected to the respective fastener of the respective coupling section. In this way, the maximum range of movement of the control wires can be adjusted both in the proximal and in the distal direction, preferably during assembly or maintenance.

Since the movable stop element is adjustably connected to the respective fastening element of one or both coupling sections, a range of movement of the control wires can be adjusted further. Thus, the deflection control mechanism may be further adaptable to a variety of steerable flexible endoscope sheaths and/or allow for adjustment due to manufacturing tolerances and maintenance requirements. Additionally, the base plate may be configured such that the fixed stop only approximately defines an allowable range of motion of the control wires, while the movable stop member is adjustable for fine adjustment and/or maintenance readjustment of the range of motion. Manufacturing costs can thus be further reduced.

According to an advantageous embodiment, the flexible section and the first and the second coupling section of the pulling element extend at least approximately in the base plane or adjacent to it and essentially parallel thereto. In particular, the longitudinal movement of the coupling sections can be carried out parallel to the base plane. Further in accordance with this embodiment, the base plate is substantially between the first and second coupling portions of the tension element arranged. In particular, the tension member may be arranged in a substantially U-shape, with the base plate being arranged between the first and second coupling portions, ie in an inner space of the U, and the fixed stopper being arranged on the base plate on an inner side of the U. Thus, the fixed stopper can be located close to the drive wheel and can be more directly and rigidly connected to an axle of the drive wheel. The fixed stop may be formed by a projection or a shoulder of the base plate and so be integral with the base plate, being formed on a longitudinal side of the base plate towards the respective coupling portion. In this way, a particularly simple, stiff and rigid design can be achieved while providing an even more rigid and clearer definition of the mechanical stop provided by the interaction of the movable stop element with the fixed stop.

The base plate is preferably made of metal, for example as a sheet metal part, and the support structure comprises at least one plastic plate which is arranged essentially parallel and adjacent to the base plate. The plastic plate can be made in one piece. The plastic plate may be substantially planar and may have protrusions and/or bores for alignment and attachment with respect to the base plate. The plastic plate can have a greater extent in the longitudinal direction than in a transverse direction. The support structure can comprise two plastic plates arranged on either side of the base plate. The one or both plastic plates are preferably arranged between the first and the second coupling section, i. H. if the tension element is U-shaped, in an inner space of the U. The one or the two plastic plates are advantageously arranged immediately adjacent to the base plate or rest against it. In particular, the metal plate and the at least one plastic plate are stacked on top of one another. One plastic sheet may be stacked on top of the base sheet and if two plastic sheets are provided the base sheet may be stacked on top of the other plastic sheet providing a friction fit. The respective plates preferably rest directly on one another and form two-dimensional contact areas to improve the friction fit. The one or both plastic plates can be fastened to the base plate, for example via one or more pins, one or more bolts and/or one or more screws, in order to increase the rigidity. The stack of the metal plate and the one or both plastic plates can form a sub-assembly that is modular in that the metal plate has the fixed stop associated with a particular type or size of endoscope shaft. Additionally, a housing of the deflection control mechanism and/or a housing or body of the handpiece may be rigidly attached to the stacked plate assembly via the one or more pins, the one or more bolts and/or the one or more screws. In this way, the stability of the support structure can be improved and an inexpensive and simple design can be provided.

If two plastic plates are provided, the plastic plates can symmetrically enclose the base plate, so that the base plate is essentially arranged in a central plane of the stack formed by the base plate and the two plastic plates. The base plane may be a middle plane of the tension member arranged in a substantially U-shape and may coincide with the middle plane of the stack. The stationary stop can thus be arranged in the central plane of the pulling element, which further improves the rigidity of the mechanical stop.

The at least one plastic plate advantageously forms a guide for the longitudinal movement of the movable stop element of the first and/or the second coupling section. In particular, the movable stop element can be guided in a channel, an inner wall of which is formed by the at least one plastic plate. The fastener can also be passed through the plastic panel or in the same channel. If the base plate is a metal plate, the at least one plastic plate can have a greater width than the metal plate, so that the movable stop element and/or the fastening element only make contact with the plastic plate. In this way, friction that might arise when the coupling portion moves during operation of the deflection control mechanism can be reduced.

The movable stop element of the first and/or the second coupling section can further advantageously be designed as a rectangular block, the movable stop element and the guide channel having a substantially rectangular cross-section. The movable stop member may have a flat stop surface on its proximal side perpendicular to the longitudinal direction for cooperating with the fixed stop of the support structure by contacting the fixed stop when the end of a range of motion has been reached. In a similar way, the fastener can be used as a substantially rech be designed teck block, which is guided in a correspondingly shaped channel.

According to a preferred embodiment of the invention, the deflection control mechanism comprises a further drive wheel rotatably supported in or on the support structure, preferably coaxially with the above drive wheel, and a further elongate tension member having a flexible portion, one connected to a first end of the flexible portion first coupling portion and a second coupling portion connected to a second end of the flexible portion. The flexible portion of the further pull member engages the further drive wheel, and the first and second coupling portions of the further pull member each include a fastener for attaching a respective proximal end of each wire of at least one further pair of control wires, the first and/or the second Coupling section of the further pull element comprise a movable stop element which cooperates with a further fixed stop of the support structure. The support structure comprises a further base plate which is arranged approximately in a further base plane which extends substantially perpendicularly to an axis of rotation of the further drive wheel, wherein the further base plate is arranged substantially parallel to the base plate and is rigidly connected thereto, and wherein the further base plate supports the further fixed stop of the support structure. The further drive wheel, the further tension element and the further base plate can be configured like the drive wheel, the tension element and the base plate which have been described above. In particular, it can be considered that the deflection control mechanism according to the present embodiment comprises, in addition to the elements of the deflection control mechanism according to the embodiments described above, further elements constituting another deflection control mechanism with a common support structure. The deflection control mechanism may be configured to control the deflection of the steerable portion of an endoscope shaft comprising two pairs of control wires for controlling the deflection of the steerable portion in two different planes, with a first pair of counteracting control wires being set by rotating the drive wheel and moving the pull member as described above deflection control in a first plane and a further pair of counteracting control wires are actuated by rotating the further drive wheel and moving the further pull member to control deflection in a second plane. The first and the second plane can be at an angle of 90° to one another. Thus, the steerable portion can be deflected in any arbitrary direction.

In a manner similar to that described above, the further movable stop element can be adjustably connected to the fastening element of the respective coupling section of the further tension element. The flexible portion and the first and second coupling portions of the further tension member may extend substantially in or adjacent to the further base plane, and the further base plate may be disposed substantially between the first and second coupling portions, which may be U-shaped. It can be considered that the base plate and the tension element form a first layer of the deflection control mechanism, and it can be considered that the further base plate and the further tension element form a second layer of the deflection control mechanism.

The further base plate is preferably a metal plate and the support structure comprises at least one further plastic plate arranged substantially parallel and adjacent to the further base plate, the further base plate and the at least one further plastic plate being stacked on top of each other. The at least one further plastic plate can be configured as the at least one plastic plate described above. The further base plate and the at least one further plastic plate are preferably between the first and the second coupling section, i. H. if the further tension element is U-shaped, arranged in an inner space of the U. The additional base plate can be arranged essentially in a central plane of the additional tension element. The one or two further plastic plates are preferably in two-dimensional contact with the base plate and rest directly on each other to improve the friction fit. The one or the two further plastic plates can be fastened to the base plate, for example via one or more pins, one or more bolts and/or one or more screws, in order to increase the rigidity. The at least one additional plastic plate can form a guide for the movement of the movable stop element and/or the fastening element of the first and/or the second coupling section of the additional tension element.

A stack formed by the base plate and the at least one plastic plate configured as above is most preferably stacked on top of the stack formed by the further base plate and the at least one further plastic plate, with an intervening separator plate being arranged between both stacks. It can therefore be considered that the first and the second layer are stacked on top of each other and an upper one or form the lower layer. The separating plate can serve to separate the guide channels of the respective tension elements of the first and second layer. The partition plate can be formed by a thin metal sheet. The arrangement of stacked plates formed from the two metal plates and the at least two plastic plates, including the separator plate, can be held together by one or more pins, one or more bolts and/or one or more screws. The plates may have protrusions, bores, and/or cutouts to facilitate alignment and/or insertion of the one or more pins, one or more bolts, and/or one or more screws. In this way, a particularly stable and rigid design of the deflection control mechanism can be achieved. The base plates and the at least two plastic plates can be held together to form a subassembly that can be prefabricated, wherein only the base plates can be associated with a particular endoscope shaft type and size, and which can be precisely and rigidly connected to, for example, a housing or a body of the handpiece can.

According to a preferred embodiment of the invention, the support structure comprises a plate-shaped frame element, the frame element being arranged substantially perpendicularly to the base plane, the frame element having a first and a second cutout and a distal end portion of the base plate being inserted into the first cutout and a distal end portion of the further base plate is inserted into the second cutout. In particular, the distal end sections of the base plate and the further base plate can each be designed as a projection which is inserted into a corresponding cutout of the frame element. The projection may be hook-shaped, the hook gripping or clipping the frame member such that the base plate and the further base plate are fixedly connected to the frame member. The base plate and the further base plate are most preferably held without play and perpendicular to a plane of the frame element in the respective cutout of the frame element. The base plate and the further base plate can each be held on the frame element via the hook-shaped projection, and the two base plates and the at least two plastic plates can form a plate stack as described above, with respective distal end sides of the plastic plates abutting the frame element. The stack of plates can thus be held together by the frame member and additional connecting elements such as pins, bolts and/or screws are not absolutely necessary. One or more plastic plates can be clamped between the base plate and the further base plate. This facilitates manufacture, so that the plate stack can be easily assembled by stacking the plates on top of one another and inserting the distal end sections of the base planes into the respective cutouts of the frame element, after which the subassembly thus formed can be connected, for example, to a housing of the deflection control mechanism and/or to a body or a housing of the handpiece is connected. Fasteners such as one or more pins, one or more bolts, and/or one or more screws may be used to mount the plate stack to a body of the handpiece, and also provide additional attachment of the plates to one another.

Advantageously, the first and second cutouts of the frame member are recesses located on opposite sides of the frame member. In particular, the cutouts are formed by cutting rectangular recesses in the plate-like frame member from an upper or lower side of the frame member, respectively. In this way, the assembly of the subassembly formed from the plate stack and the frame element can be further simplified.

The frame member more preferably has a plurality of bores or further cutouts for holding respective sheaths of the wires of the at least two pairs of control wires. In particular, respective wire spool holders can be inserted into the bores or cutouts, the wire spool holders being designed for holding wire spools in which the respective control wires are routed. The bores or cutouts may be formed perpendicular to the base plane so that each coil of wire is maintained aligned in the longitudinal direction of the respective coupling portion. This allows the control wires to be routed to minimize friction and wear.

Advantageously, the support structure comprises a cage structure in which the drive wheel and preferably the further drive wheel are rotationally supported, for example on a fixed axle, the axle being held in the cage structure. The cage structure is preferably rigid, with the axle being rigidly fixed in the cage structure. Further, the support structure may comprise a housing of the deflection control mechanism, the housing being rigidly connected directly or indirectly to the base plate and preferably to the further base plate and rigidly connected to the cage structure or supported at least in the longitudinal direction on the cage structure. The support structure can be a body of the include handpiece. The cage structure, housing and/or handpiece body may be rigidly connectable to the subassembly formed of the metal plates, plastic plates and frame member as described above. In this way, a particularly stable and rigid connection can be achieved between a bearing of the drive wheel and the stationary stop, as a result of which the rigidity of the mechanical stop is further improved.

According to a further aspect of the present invention, a steerable flexible endoscope has an elongate flexible shaft comprising a steerable portion which is deflectable and bendable by longitudinal movement of at least one pair of opposing control wires, the flexible endoscope further comprising a deflection control mechanism as described above is designed. In particular, the endoscope may include a handpiece connected to a proximal end of the flexible shaft, the deflection control mechanism being housed in the handpiece, the proximal ends of the wires of the at least one pair of opposing control wires being secured in the respective fasteners of the deflection control mechanism. Most preferably, the steerable portion is deflectable by movement of two pairs of control wires in two perpendicular planes, and the deflection control mechanism is adapted to actuate two pairs of control wires to control deflection in two perpendicular planes as described above.

According to another aspect of the present invention, there is provided an endoscope assembly kit comprising at least first and second elongate flexible shafts, each elongate flexible shaft comprising a steerable portion deflectable by movement of at least one pair of opposing control wires, wherein the the first and second elongate shafts have different allowable ranges of longitudinal movement of the control wires. The first and second elongate shanks may have different shank diameters, different shank lengths, different maximum deflection angles, and/or may differ in other properties resulting in different allowable ranges of longitudinal movement of the control wires. The endoscope assembly kit further includes a deflection control mechanism configured to control deflection of the steerable portion of the first elongate flexible shaft, the deflection control mechanism being configured as described above. The deflection control mechanism thus includes a first base plate supporting a fixed stop whose longitudinal position is matched to an allowable range of motion of the at least one pair of opposing control wires of the first elongate shaft. The deflection control mechanism is connectable to the proximal end of the first elongate flexible shaft.

According to this aspect of the invention, the endoscope assembly kit further includes a second base plate supporting a fixed stop whose longitudinal position is matched to an allowable range of motion of the at least one pair of opposing control wires of the second elongate shaft. The longitudinal position of the fixed stop of the second base plate thus differs from the longitudinal position of the fixed stop of the first base plate. The first base plate is interchangeable with the second base plate to accommodate the deflection control mechanism for controlling the deflection of the steerable portion of the second elongate flexible shaft. The deflection control mechanism is also connectable to the proximal end of the second elongate flexible shaft. The endoscope assembly kit preferably includes, in addition to the first and second base plates, other first and second base plates that are adapted to respective allowable ranges of motion of another pair of control wires of the first and second flexible shafts. In this way, an endoscope assembly kit can be provided that allows for easy reconfiguration of the deflection control mechanism, thereby increasing versatility and reducing cost.

Additionally, the endoscope assembly set may include deflection control mechanism elements including the second base plate, thereby forming a subassembly set to be assembled to form a second deflection control mechanism configured to control the deflection of the steerable portion of the second elongate flexible shaft. Specifically, the subassembly set includes a drive wheel, an elongate traction member, and members of a support structure including the second base plate. Instead of the first deflection control mechanism, the endoscope assembly set may include elements for assembling the first deflection control mechanism, thereby forming a corresponding sub-assembly set that includes the first base plate. The endoscope assembly kit may thus comprise at least two identical specimens of each element mentioned, including at least two identical pulling elements comprising the movable stop elements other than the base plates located at the position of the respective fixed stop differ because they are selected according to the shaft in question.

Advantageously, the movable stop element can be adjustably connected to a respective fastening element of an elongate pulling element or can be connected to this. In this case, the fixed stopper can be supported by one of the first and second base plates in a position only approximately corresponding to an allowable range of movement of the control wires of each of the flexible shafts, while fine adjustment of each allowable range of movement can be achieved by moving the movable stopper member . In this way, fine adjustment during manufacture and/or readjustment for maintenance can be facilitated.

The set of assemblies preferably includes three or more flexible shafts and a corresponding number of base plates which may differ in the position of the fixed stop to match the allowable range of longitudinal movement of the control wires of each respective flexible shaft. The endoscope assembly set can therefore be considered modular in that the deflection control mechanism can be adapted to any one of the flexible shafts while only the base plates are specific to a particular one of the shafts. Manufacturing inventory and manufacturing planning expenses may be reduced due to the reduced number of elements and/or increased amount of standardized elements of the deflection control mechanism.

The present invention further relates to a method of assembling a deflection control mechanism for a flexible endoscope, the flexible endoscope having an elongate flexible shaft that includes a steerable portion that is deflectable by moving at least one pair of opposing control wires. According to the method, the elongate flexible shaft of the endoscope is provided, and a deflection control mechanism is provided, wherein the deflection control mechanism is configured as described above, wherein the base plate supports a fixed stop that is adapted to an allowable range of motion of the at least one pair of opposing control wires of the long extended shaft is adjusted. According to the method, the deflection control mechanism is connected to a proximal end of the elongate flexible shaft, with the proximal ends of both wires of the at least one pair of opposing push-pull wires being secured in the respective fasteners of the first and second coupling portions of the deflection control mechanism. In a subsequent or preceding step, the deflection control mechanism may be covered by a housing of a handpiece of the endoscope or inserted into the handpiece. Thus, the flexible endoscope is easy to assemble using inexpensive and simple components.

The step of providing the deflection control mechanism may include the steps of providing the support structure, including the base plate with the fixed stop, and further providing the drive wheel and the elongate tension member, wherein the support structure, the drive wheel and the elongate tension member are as described above are configured, and mounting the deflection control mechanism. The support structure can have a stack of plates as described above, wherein for example the base plate is designed as a metal plate and at least one plastic plate is stacked on top. The stack of plates may further include a separator plate, another base plate which is another metal plate, and at least one other plastic plate.

The step of assembling the deflection control mechanism may include the steps of stacking the plates together and connecting the stack of plates to other elements of the support structure such as a handpiece body and/or a cage structure holding an axle of the drive wheel. The step of stacking the plates on top of each other may include the step of inserting the respective distal end portions of the base plate and the further base plate into respective cutouts of a frame member arranged substantially perpendicular to the base plane, whereby at least one of the plastic plates is sandwiched between the base plate and the further base plate is clamped, whereby the plate stack can be held together without further fasteners and forms a subassembly. This subassembly is connected to other elements of the support structure such as the handpiece body and/or the cage structure as described above. Thus, assembly of the deflection control mechanism can be further facilitated.

Before the plates are stacked, the base plate may be appropriately selected from a plurality of base plates or machined such that a longitudinal position of the fixed stopper is at least approximately matched to an allowable longitudinal movement range of the control wires of the flexible shaft; the same can apply to the further base plate. If the movable stop element adjustable with the fastener of the respective Koppe l portion of the elongate pulling element is connected or adjustably connectable thereto, a longitudinal position of the movable stop element can be adjusted with respect to the respective fastening element for fine adjustment to the allowable range of movement of the control wires. In this way, a particularly simple and cost-effective method for mounting a flexible endoscope can be provided.

The deflection control mechanism may include other features such as a braking mechanism as known from co-pending patent application "Deflection control mechanism for a steerable flexible endoscope, steerable flexible endoscope, and method for controlling a flexible endoscope" (internal file number P01722) and/or further details include as known from co-pending patent application "Deflection control mechanism for a steerable flexible endoscope, steerable flexible endoscope, endoscope assembly set, and method for assembling a flexible endoscope" (internal file number P01723), both by the same applicant filed on the same date as the present application and are hereby incorporated by reference into the present application.

The features of the invention mentioned above and described below apply not only in the combinations mentioned, but also in other combinations or alone, without departing from the scope of protection of the present invention.

• 1 zeigt ein lenkbares flexibles Endoskop in einer Gesamtansicht;
• 2 zeigt einen Ablenksteuerungsmechanismus nach einem Ausführungsbeispiel der vorliegenden Erfindung;
• 3 zeigt den Ablenksteuerungsmechanismus wie in 2, jedoch in einer vergrößerten, horizontalen Längsschnittansicht;
• 4 zeigt einen proximalen Teil des Ablenksteuerungsmechanismus aus 2 in einer vergrößerten, vertikalen Längsschnittansicht;
• 5 zeigt den Ablenksteuerungsmechanismus aus 2 in einer vergrößerten Querschnittsansicht;
• 6 zeigt eine Anordnung von gestapelten Platten des Ablenksteuerungsmechanismus auf 2 in einer Perspektivansicht;
• 7 zeigt den Ablenksteuerungsmechanismus aus 2 aus einer distalen Richtung;
• 8 zeigt die distale Seite der Anordnung aus gestapelten Platten aus 6 mit dem Rahmenelement in Durchsicht;
• 9 zeigt Elemente eines Anordnungssatzes des Ablenksteuerungsmechanismus aus 2 - 9.

Further aspects of the present invention will become apparent from the figures and from the description of a specific embodiment that follows.

• 1 shows a steerable flexible endoscope in an overall view;
• 2 Fig. 12 shows a deflection control mechanism according to an embodiment of the present invention;
• 3 shows the deflection control mechanism as in FIG 2 , but in an enlarged, horizontal longitudinal sectional view;
• 4 Figure 12 shows a proximal part of the deflection control mechanism 2 in an enlarged vertical longitudinal sectional view;
• 5 shows the deflection control mechanism 2 in an enlarged cross-sectional view;
• 6 Figure 12 shows an arrangement of stacked plates of the deflection control mechanism 2 in a perspective view;
• 7 shows the deflection control mechanism 2 from a distal direction;
• 8th Figure 12 shows the distal side of the stacked plate assembly 6 with the frame element in view;
• 9 Fig. 12 shows elements of a set of assemblies of the deflection control mechanism 2 - 9 .

As schematic in 1 1, a flexible endoscope 10 typically includes a handpiece 20 and an elongate flexible shaft 30, with the handpiece 20 being attached to a proximal end of the shaft 30. As shown in FIG. The handpiece 20 has an outer casing 21 made of a plastic and/or metallic material. On a lower side of the casing 21, a first hand wheel 22 and a second hand wheel 23 for controlling a deflection of a steerable portion 31 of the shaft 30 are arranged as shown in FIG is described below. The first and second handwheels 22, 23 are usually arranged coaxially, and on an outer side of the second handwheel 23, a knob 24 for controlling a deflection brake with respect to the second handwheel 23 is provided. In addition, the handpiece 20 may include a variety of control buttons 25 for controlling various functions of the flexible endoscope 10, such as controlling the imaging and/or illumination system and/or irrigation and suction pumps. The handpiece 20 can be connectable to an external video unit or video monitor via a connector 26 and to an external light source via a light cable 27 . An instrument port 28 may also be provided for insertion of endoscopic instruments to be advanced through one or more respective channels to a distal end of shaft 30 to manipulate tissue or other objects in a lumen into which shaft 30 may be inserted.

At its distal end, the flexible shaft 30 comprises a steerable section 31. The steerable section 31 can form a distal end section of the shaft 30 or, as in FIG 1 1, carry a distal end cap 32 which may house imaging optics and an electronic imaging sensor for providing an endoscopic image of a lumen into which the shaft 30 is inserted. The image signal produced by the image sensor may be transmitted via electrical cables extending through shaft 30 and handpiece 20 to connector 26 for processing and display by an external video unit. The overall shaft 30 is flexible enough to be advanced through an endoscopic port or lumen to a cavity to be viewed because it can conform to a curved shape of the port or organ. The steerable section 31, on the other hand, can be activated by turning the hand wheels 22, 23 be bent. For this purpose, the steerable section 31 comprises an internal structure made up of a large number of consecutive pivoting elements 33 and can thus be deflected in one or more planes. The pivot members 33 are covered by a hose to form a smooth outer surface, with the shank 30 having an overall uniform cross-sectional shape and diameter.

To control the deflection of the steerable section 31, two opposing control wires (in 1 not shown) which extend on opposite sides in the steerable section 31 and by the longitudinal movement of which the steerable section 31 can be bent to one side or the other, as symbolically in FIG 1 implied. The control wires extend along the shaft 30 and are connected at their proximal ends to a deflection control mechanism located in the handpiece 20 which can be actuated to deflect the steerable portion 31 by a user turning the handwheels 22,23. In the embodiment shown, the steerable portion can be bent in a first plane, which corresponds to the plane of the drawing, the angle of deflection being controllable by turning the first hand wheel 22 . Furthermore, the steerable section 31 can be bent in a second plane perpendicular to the first plane and perpendicular to the plane of the drawing, a corresponding deflection angle being controllable by turning the second hand wheel 23 .

2 12 shows a lower portion of a handpiece 20 of a flexible endoscope according to an embodiment of the invention, with an upper part of the housing 21 of the handpiece 20 and an inner half-shell housing having been removed to show elements of the deflection control mechanism 29. FIG. The handpiece 20 can further, in 2 include items not shown (see 1 ). As in 2 As shown, a lower portion of the housing is formed by a handpiece body 40 which is preferably formed of metal such as stainless steel. On its lateral sides the body 40 carries a sealing ring 41 made of an elastic sealing material to form a sealed connection with the upper part of the housing (in 2 Not shown); thus, an interior space of the handpiece 20 in which the deflection control mechanism 29 is housed is sealed. On a lower side of the body 40, the first hand wheel 22 and the second hand wheel 23 are rotatably mounted and have a common axis of rotation. The common axis is defined by an axle 43 which does not rotate and is held stationary in a rigid metal cage 44 . The axis defines an axis of rotation of a drive wheel (pinion 59, see below) rotationally coupled to the second handwheel 23 and another drive wheel (pinion 69) rotationally coupled to the first handwheel 22. A lever 42 is provided for controlling a deflection brake relative to the first hand wheel 22 .

Also shows 2 the proximal end portions of the sheaths 35, 35', 36, 36' by two pairs of opposing control wires; the control wires continue to the right side of the drawing and extend through the shaft 30 of the endoscope to the steerable section 31 (see Fig 1 ). The wire sleeves 35, 35', 36, 36' are each held securely in a respective wire spool holder 51, 51', 61, 61'. The proximal end portions of the control wires 37, 38 protrude from the sheaths 35, 36, respectively. Correspondingly, the proximal end portions of respective counteracting control wires of the two pairs of control wires protrude from the respective sheaths 35', 36', wherein in 2 only the control wire 37' is visible. The control wires 37, 37' are each mounted in a respective mounting member (rectangular mounting blocks 52, 52') which is connected to a chain 58. The chain 58 takes the teeth of a drive wheel (pinion 59, see 3 ) engages and wraps around the drive wheel, thereby enclosing an angle of 180°, connecting the mounting block 52 to the corresponding mounting bracket 52' on the other side of the deflection control mechanism. The chain 58 consists of a large number of segments which are connected to one another via hinges which are not shown in the figures for reasons of clarity. There is also a stop block 56 connected to the mounting block 52 and a stop block 56' connected to the mounting block 52', the stop blocks 56, 56' forming movable stop members which cooperate with corresponding fixed stops (see below ). Furthermore, a tensioning mechanism can be provided so that the control wires 37, 37' are subjected to a pretension.

The chain 58 can thus be considered a flexible portion of a traction element which engages the drive wheel (sprocket 59). Rotation of sprocket 59 moves both ends of chain 58 and connected coupling portions formed by members 52 and 56 and respective members 52' and 56' in opposite directions causing corresponding opposite movement of control wires 37, 37'. In this way, the deflection of the steerable section 31 of the endoscope 10 can be controlled in a first plane (see FIG 1 ).

In the present example, the deflection control mechanism 29 comprises two tiers 50, 60 - an upper tier 50 configured to control deflection of the steerable portion 31 in the first plane by reciprocating longitudinal movement of the upper pair of control wires 37, 37', and a lower layer 60 adapted to control deflection of the steerable portion 31 in a second plane perpendicular to the first plane by reciprocating longitudinal movement of the lower control wires (of which only control wire 38 in 2 is visible) is designed. The lower layer 60 is configured in a similar manner, as described above, so that the deflection of the steerable portion 31 of the endoscope 10 in a direction perpendicular to the first plane can be controlled by movement of the lower pair of control wires 38, 38'. Both layers 50, 60 comprise members of a support structure and are stacked one on top of the other, being mounted on an upper side of the body 40, as described in more detail below. The upper tier 50 of the deflection control mechanism 29 is actuated by turning the second hand wheel 23 while the lower tier 60 of the deflection control mechanism 29 is actuated by turning the first hand wheel 22 .

3 FIG. 14 is a partial longitudinal sectional view, the cross section being approximately in a median plane of the top sheet 50. FIG. As in 3 As shown, the mounting block 52 has a longitudinal bore 53. A ferrule 54 is inserted into the bore 53 from a distal side, the ferrule 54 holding the proximal end of the control wire 37 in place. A threaded rod 55 is threaded into the proximal end of bore 53 on a proximal side of block 52 . For clarity, the thread formed on the substantially cylindrical surface of rod 55 is not shown in the figures. The threaded rod 55 carries a stop block 56 which forms a movable stop element. The stop block 56 has a substantially rectangular cross-section and is threaded onto the threaded rod 55 with the threaded rod 55 extending through a bore of the stop block 56 .

During assembly of the endoscope, a longitudinal position of the stop block 56 relative to the mounting block 52 can be adjusted by rotating the stop block 56, thereby advancing it in a proximal or distal direction on the threaded rod 55. During operation of the deflection control mechanism, the rectangular block 52 is guided in a correspondingly shaped channel and thus prevented from rotating; the stop block 56 is guided in the same channel as the mounting block 52 such that rotation of the stop block 56 is prevented and the longitudinal position of the stop block 56 relative to the mounting block 52 is fixed. The mounting block 52' and adjustable stop block 56' relating to the other of the upper pair of control wires 37, 37' are configured correspondingly, as are the respective elements of the lower tier 60 (Fig 2 and 3 only mounting block 62, rod 65, stop block 66, hinge 67 and chain 68 are visible) relating to the lower pair of control wires 38, 38'.

4 12 shows the proximal end portion of the deflection control mechanism 29 in a vertical longitudinal cross section. How out 4 As can be seen, the pinion gear 59 of the upper tier 50 is rigidly supported on a linkage shaft 46 which extends to a lower side of the handpiece 20 to the second handwheel 23 to which it is connected, to be rotated by turning the handwheel 23 . Similarly, a pinion 69 of the lower tier 60 of the deflection control mechanism is mounted on a further linkage shaft 47 which extends coaxially with the linkage shaft 46 into the first handwheel 22 to which it is connected, for rotation when the handwheel 22 is rotated. The pivot shaft 46 and hence the pinion 59 of the upper tier 50 of the deflection control mechanism 29 is supported by a ball bearing 48 on the rigid axle 43 which is held firmly in the cage 44. The pivot shaft 47 of the lower layer 60 is supported by a ball bearing 49 in a cage body 44a fixedly connected to the cage 44. As shown in FIG. In an alternative embodiment (not shown), the linkage shafts 46, 47 may be coupled to respective electric motors so that the pinions 59, 69 may be motor driven to actuate the deflection control mechanism 29 under motor or robotic control.

How further in 4 As shown, the upper tier 50 of the deflection control mechanism comprises a metal plate 71, an upper plastic plate 70 and a lower plastic plate 72 stacked one on top of the other. A top plate of an inner half-shell housing 45 of the deflection control mechanism 29 is arranged on the top plastic plate 70 . The plates 70, 71, 72 are held together by a vertical bolt 73 and including the housing 45 by a screw 74. The lower tier 60 is separated from the upper tier 50 by a separator plate 75 formed of thin sheet metal. The lower layer 60 comprises a further plastic plate 76 and a further metal plate 77 which are also stacked on top of each other and are held together by the bolt 73 and the screw 74. Further, the arrangement of stacked plates over the bolts 73 and the screw 74 is fixed to a raised portion 40a of the handpiece body 40. The metal plates 71, 77 can be made of stainless steel, for example. The plates 70, 71, 72, 75, 76, 77 each preferably make extensive contact with the respective adjacent plates and provide a firm frictional engagement and may also have cooperating alignment features such as projections and/or cutouts. The assembly of stacked plates of the top and bottom layers 50, 60 thus forms a rigid unit and is rigidly attached to the body 40 of the handpiece 20. Further, the cage 44 and the cage body 44a are fixedly held to the body 40 via a screw 44b, and the cage 44 is also supported in a longitudinal direction by directly abutting the housing 45 and a rigid support structure including the cage and the cage body 44, 44a, the axle 43, the stack of plates 70, 71, 72, 75, 76, 77, the body 40 and the frame member 78 (see below).

How out 3 As can be seen, the metal plate 71 of the top sheet 50 has a step or shoulder 80 which projects in a transverse direction to form a fixed stop which limits the movement of the stop block 56. FIG. Similarly, a shoulder 80' on the opposite side of metal plate 71 forms a fixed stop which limits movement of stop block 56'. As described above, the metal plate 71 is enclosed in a rigid pack of stacked plates, the pack being rigidly connected to the cage 44 which supports the pinion 59 so that the shoulders 80, 80' and the stop blocks 56, 56' cooperate by contacting each other to form a well defined stop which limits the range of motion of the first pair of control wires 37, 37'. The metal plate 71 forming the shoulders 80, 80' is arranged substantially in a median plane of the stack formed by the plates 70, 71 and 72. The pinion 59, the chain 58, the threaded rods 55, 55' and the stop blocks 56, 56' are arranged substantially symmetrically with respect to this median plane. Tilting of stop block 56 or 56' due to contacting shoulder 80 or 80' is thus minimized.

The arrangement of stacked plates is in 5 shown in a vertical cross-section drawn perpendicular to the longitudinal direction and cutting through the mounting blocks 52, 52'. The panels 70, 71, 72 of the top sheet 50 form a substantially rectangular block, with the mounting blocks 52, 52' being guided on the lateral sides of the plastic panels 70,72. The metal plate 71 has a smaller width than the plastic plates 70, 72 to avoid contact with the mounting blocks 52, 52'. Thus, rotation of the mounting blocks 52, 52' is prevented while the plastic plates 70, 72 provide low friction guidance. Similarly, the stop blocks 56, 56' are guided by the lateral sides of the plastic plates 70, 72 preventing rotation while providing low friction. Similarly, the mounting blocks 62, 62' and the stop blocks of the lower tier 60 are guided on the lateral sides of the plastic plate 76 of the lower tier 60. FIG. The partition plate 75 is positioned between the upper tier 50 and the lower tier 60 to separate the channels in which the mounting blocks 52, 52', 62, 62' and the stop blocks 56, 56', 66 are routed. Both the mounting blocks 52, 52' and the stop blocks are preferably made of metal, such as brass, which further reduces friction with the plastic plates 70,72,76. The assembly of stacked panels 70, 71, 72 of the upper tier 50, the intermediate partition panel 75 and the panels 76, 77 of the lower tier 60 are supported on a raised portion 40a of the body 40 of the housing 21 and rigidly connected thereto.

6 shows the stacked arrangement of plates 70, 71, 72, 75, 76, 77 in an oblique view shafts 46,47. On a distal side, the metal plates 71, 77 forming the base plates of the upper and lower tiers 50, 60, respectively, are held in a frame member 78. FIG. The frame member 78 is plate-shaped and is positioned substantially perpendicular to the plates 71,77. As described in detail below, the frame member 78 has first and second cutouts, or with reference to the orientation of the frame member 78 as shown in the figures, upper and lower cutouts 81, 82 in the distal end portions (hook 71a, 77a) of the metal plates 71, 77 are inserted. Furthermore, the frame element 78 has lateral cutouts 83, 83', 84, 84' in which the wire spool holders 51, 51', 61, 61' are held. The frame member 78 can be made of stainless steel, for example. The stack of plates 70, 71, 72, 75, 76, 77 can form a pre-assembled sub-assembly with the metal plates 71, 77 having the fixed stops being mated to the flexible shaft 30.

The representation in 7 and 8th Fig. 12 shows the distal end of the stacked plate assembly of Fig 6 from a substantially distal direction showing a distal side of frame member 78. Also 7 Figure 1 shows the control wires 37, 37', 38, 38' and wire coils 35, 35', 36, 36' of a flexible shaft connected to the deflection control mechanism. 8th shows the dis Tale side of the frame member 78 in a perspective view, wherein the frame member 78 is drawn in phantom.

How out 7 and 8th As can be seen, a top cutout 81 is cut in a top side of the frame member 78 and is configured as a generally rectangular recess. A distal end portion of the metal plate 71 of the top sheet 50 is formed as a hook 71a extending in a distal and lateral direction. The hook 71a is inserted into the upper cutout 81 of the frame member 78 so that the metal plate 71 is held on the frame member 78. As shown in FIG. Similarly, a distal end portion of the metal plate 77 of the lower sheet 60 forms a hook 77a which is inserted into a substantially rectangular lower cutout 82 cut in a lower side of the frame member 78 so that the metal plate 77 is attached to the frame member 78 is held. The plastic plates 70, 72, 76 and the intermediate partition plate 75 contact the proximal side of the frame element 78 with their respective distal end surfaces. The metal plates 71, 77, the plastic plates 70, 72, 76 and the partition plate 75 are stacked to form a plate stack, with the plates 72, 75 and 76 being sandwiched between the metal plates 71, 77 and held by a clamping force exerted by the frame member 78 will. The plate stack is further held together by at least one bolt 73 and by screws 74,85.

The metal plate 77 of the lower tier 60 rests on a raised portion 40a of the body 40. The stack of plates 70,71,72,75,76,77 is secured to the body 40 by bolts 73 and screws 74,85. The raised portion 40a is formed at a step portion 40b which is in turn provided at a reinforcement portion 40c of the body 40. As shown in FIG. The reinforcement portion 40c serves to improve the rigidity of the body 40 and the stack of plates 70,71,72,75,76,77. The reinforcement portion 40c is cut out in a distal portion of the body 40 and recessed on lateral sides of the step portion 40b in another portion of the body 40, as shown in FIG 5 is evident.

The frame member 78 further includes side cutouts 83, 83', 84, 84' formed by substantially semi-circular cutouts cut in the lateral sides of the frame member 78 (see Fig 6 ). The wire coil holders 51, 51', 61, 61' each have a rectangular proximal end portion 51a, 51a', 61a, 61a' and a rectangular distal end portion 51b, 51b', 61b, 61b' which are covered by a cylindrical sheath 51c, 51c' , 61c, 61c' are connected (see 8th ). The cylindrical sleeves 51c, 51c', 61c, 61c' are inserted into respective ones of the side cutouts 83, 83', 84, 84' so that the wire spool holders 51, 51', 61, 61' are fixed to the frame member 78 and thereby secured to the stack of plates 70,71,72,75,76,77. The wire coils 35, 35', 36, 36' of the flexible shaft 30 can be inserted into the proximal end pieces 51a, 51a', 61a, 61a' and/or into the cylindrical sheaths 51c, 51c', 61c, 61c' so that the control wires 37, 37', 38, 38' proceed in a proximal direction to be fixed in the fixing blocks 52, 52', 62, 62'.

The semicircular recesses forming the side cutouts 83, 83', 84, 84' are machined so that their respective axes coincide with the proximal end portions of a respective one of the wire coils 35, 35', 36, 36' and the respective control wires 37, 37'. , 38, 38' are aligned to avoid kinking of the control wires 37, 37', 38, 38' and to minimize wear. The rectangular proximal end pieces 51a, 51a' of the wire coil holders 51, 51' contact a respective side surface with the corresponding lateral side surfaces of the plastic plates 70, 72, so that rotation of the wire coil holders 51, 51' is restricted. Similarly, to prevent rotation, the rectangular proximal end pieces 61a, 61a' of the wire coil holders 61, 61' of the lower layer 60 abut their respective side surfaces against the lateral side surfaces of the plastic plate 70 and preferably the raised portion 40a of the body 40.

The metal plates 71, 77, the plastic plates 70, 72, 76 and the partition plate 75 are in 9 shown individually. 9 also shows two bolts 73 and the frame member 78. As in FIG 9 As can be seen, the metal plates 71, 77 forming the base plates of the top and bottom tiers 50, 60, respectively, are basically similar in configuration; however, metal plate 71 has shoulders 80, 80' at a first longitudinal position and metal plate 77 has shoulders 90, 90' formed at a slightly different longitudinal position to cooperate with stop blocks 66 of lower tier 60 to provide a range of motion of the Limit control wires 38, 38' accordingly. Furthermore, the plastic plates 70, 72, 76 are configured the same or almost the same.

A deflection control mechanism 29 and a flexible shaft 30 are provided for assembling a flexible endoscope 10 according to an example method. For assembling the deflection control mechanism 29, the metal plates 71, 77, the plastic plates 70, 72, 76, the partition plate 75, the frame member 78 and one or more bolts 73 are provided as in FIG 9 shown. the Metal plates 71, 77 are machined accordingly, or may be selected from a variety of metal plates which are similar except for a longitudinal position of the shoulders 80, 80', 90, 90' according to an allowable range of longitudinal movement of the control wires 37, 37', 38 , 38' of the flexible shaft 30 to which the deflection control mechanism 29 is adapted to control the deflection of the steerable portion 31. Also provided are a body 40, screws 74, 85 and the other elements of the deflection control mechanism 29 as described above.

The plates 70, 71, 72, 75, 76, and 77 are stacked on each other, and the distal end portions (hooks 71a, 77a) of the metal plates 71, 77 are inserted into the cutouts 81, 82 of the frame member 78 so that the plates 72, 75, 76 are clamped between the metal plates 71, 77. Stacking and alignment of panels 70, 71, 72, 75, 76, and 77 may be aided by alignment features such as tabs and/or cutouts on the panels. The subassembly formed by the stack of panels 70, 71, 72, 75, 76, 77 is thus held together by the frame member 78. The stack can be further stabilized by inserting one or more bolts 73 into respective holes.

Thereafter, the stack of plates 70,71,72,75,76,77 is placed on the raised portion 40a of the body 40 and secured to the body 40 by screws 74,85. The wire spool holders 51, 51', 61, 61' are inserted with their sleeves 51c, 51c', 61c, 61c' into a respective one of the side cutouts 83, 83', 84, 84'. Further, the above other members of the support structure are assembled, the drive wheels (pinion gears 59, 69) are assembled, and the elongate tension members are engaged with the drive wheels to assemble the deflection control mechanism configured as described above.

If the longitudinal position of the shoulders 80, 80', 90, 90' of the metal plates 71, 77 is adjusted precisely or with sufficient accuracy to the permissible range of movement of the control wires 37, 37', 38, 38' of the flexible shaft 30, no further measures are necessary to adjust the deflection control mechanism 29. If, on the other hand, the longitudinal position of the shoulders 80, 80', 90, 90' of the metal plates 71, 77 is only approximately and not sufficiently precisely adapted to the permissible range of movement of the control wires 37, 37', 38, 38', the stop blocks 56, 56 ', 66 on the respective threaded rod 55, 55', 65, 65' to finely adjust the travel limit of the respective control wires 37, 37', 38, 38'. For this purpose, the arrangement of stacked plates 70, 71, 72, 75, 76, 77 can be partially dismantled, or the stop blocks 56, 56', 66 can be pulled out laterally from a respective guide channel. After adjustment, the stack of plates 70, 71, 72, 75, 76, 77 is reattached as described, or the stop blocks 56, 56', 66 are reinserted into the respective guide channel. Finally, an inner half-shell housing 45 can be assembled, covering the deflection control mechanism on an upper and lateral sides. Thus, the deflection control mechanism is easily assembled and adapted to a particular flexible shaft 30 using inexpensive and simple components.

The deflection control mechanism is connected to a proximal end of the elongate flexible shaft 30, with the proximal ends of the wire coils 35, 35', 36, 36' being mounted in the wire coil mounts 51, 51', 52, 52' and the proximal ends of the control wires 37, 37', 38, 38' are fixed in the respective mounting blocks 52, 52', 62, 62'. In a subsequent or previous step, the deflection control mechanism 29 can be covered with a housing of a handpiece 20 of the endoscope 10 or inserted into the handpiece 20 .

In the above description, the terms "upper" and "lower" refer to the orientation of the handpiece 20 and deflection control mechanism 29 as shown in the figures. Any other orientation can be chosen by a user according to requirements during use.

For the sake of clarity, not all reference numbers are shown in all figures. If a reference number is not expressly mentioned in the description of a figure, it has the same meaning as in the other figures.

Reference List

10

Flexible endoscope

20

handpiece

21

casing

22

handwheel

23

handwheel

24

button

25

button

26

Interconnects

27

light cable

28

instrument port

29

deflection control mechanism

30

shaft

31

Steerable section

32

end cap

33

swivel element

35, 35'

covering

36, 36'

covering

37, 37'

control wire

38, 38'

control wire

40

body

40a

Elevated section

40b

step section

40c

reinforcement section

41

sealing ring

42

lever

43

axis

44

Cage

44a

cage body

44b

screw

45

half-shell housing

46

shaft

47

shaft

48

ball-bearing

49

ball-bearing

50

Upper layer

51, 51'

Wire Spool Bracket

51a, 51a'

Proximal end piece

51b, 51b'

Distal tail

51c, 51c'

covering

52, 52'

block

53, 53'

drilling

54, 54'

ferrule

55, 55'

pole

56, 56'

block

57, 57'

hinge

58

Chain

59

pinion

60

Lower class

61, 61'

Wire Spool Bracket

61a, 61a'

Proximal end piece

61b, 61b'

Distal tail

61c, 61c'

covering

62, 62'

block

65

pole

66

block

67

hinge

68

Chain

69

pinion

70

plastic plate

71

metal plate

71a

hook

72

plastic plate

73

bolt

74

screw

75

partition plate

76

plastic plate

77

metal plate

77a

hook

78

frame element

80, 80'

shoulder

81

cutout

82

cutout

83, 83'

cutout

84, 84'

cutout

85

screw

90, 90'

shoulder

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• EP 2835096 B1 [0007]
• EP 3222195 A1 [0008]

Claims (15)

A deflection control mechanism for a steerable flexible endoscope (10), the endoscope (10) having an elongate flexible shaft (30) comprising a steerable portion (31) operable by movement of at least a pair of opposing control wires (37, 37', 38 , 38') is deflectable, the deflection control mechanism (29) comprising a support structure, a drive wheel rotatably supported in or on the support structure, and an elongate tension member having a flexible portion, a first coupling portion connected to a first end of the flexible portion, and having a second coupling portion connected to a second end of the flexible portion, the flexible portion of the traction member engaging the drive wheel, the first and second coupling portions each having a fastener for attaching a respective proximal end of each wire of the at least one pair of control wires (37, 37', 38, 38'). en, and wherein the first and/or the second coupling section comprise a movable stop element which interacts with a fixed stop of the support structure, characterized in that the support structure comprises at least one base plate which is arranged essentially in a base plane which is at least approximately extends perpendicularly to an axis of rotation of the drive wheel, wherein the base plate supports the fixed stopper. deflection control mechanism claim 1 , characterized in that the movable stop element is adjustably connected to the fastening element of the respective coupling section. deflection control mechanism claim 1 or 2 , characterized in that the flexible portion and the first and the second coupling portion of the tension element extend substantially in the base plane or adjacent thereto and that the base plate is arranged substantially between the first and the second coupling portion. Deflection control mechanism according to one of Claims 1 - 3 , characterized in that the base plate is a metal plate (71, 77) and in that the support structure comprises at least one plastic plate (70, 72, 76) arranged substantially parallel to and adjacent to the base plate, the metal plate (71, 77) and the at least one plastic plate (70, 72, 76) are stacked on top of each other. deflection control mechanism claim 4 , characterized in that the at least one plastic plate (70, 72, 76) forms a guideway for the movement of the movable stop element and/or the fastening element of the first and/or second coupling section. A deflection control mechanism as claimed in any one of the preceding claims, characterized in that the deflection control mechanism comprises a further drive wheel which is rotatably supported in or on the support structure and a further elongate tension element which has a flexible section, a first coupling section which is connected to a first end of the flexible section, and having a second coupling section connected to a second end of the flexible section, the flexible section of the further traction element being engaged with the further drive wheel, the first and second coupling sections of the further traction element each having a fastening element for Attaching a respective proximal end of each wire comprises at least one further pair of control wires (38, 38'), wherein the first and/or the second coupling portion of the further traction element comprises a movable stop element which is connected to a further fixed stop of the Support structure interacts, wherein the support structure comprises a further base plate, which is arranged approximately in a further base plane, which extends essentially perpendicularly to an axis of rotation of the further drive wheel, wherein the further base plate is arranged essentially parallel to the base plate and is rigidly connected to it , and wherein the further base plate supports the further fixed stop. deflection control mechanism claim 6 , characterized in that the further base plate is a metal plate (77) and in that the support structure comprises at least one further plastic plate (76) which is arranged substantially parallel to and adjacent to the further base plate, the further base plate and the at least one further Plastic plate (76) are stacked. deflection control mechanism claim 7 in combination with claim 4 , characterized in that a stack formed from the metal plate (71) and the at least one plastic plate (70, 72) is stacked on top of a stack formed from the further metal plate (77) and the at least one further plastic plate (76), with a separating plate (75) is arranged between both stacks. Deflection control mechanism according to one of Claims 6 - 8th , characterized in that the support structure comprises a frame member (78) disposed substantially perpendicular to the base plane, the frame member (78) having first and second cutouts (81, 82) in respective distal end portions of the base plate and the other base plate are introduced. deflection control mechanism claim 9 characterized in that the cutouts (81, 82) of the frame member are recesses formed on opposite sides of the frame member (78). deflection control mechanism claim 9 or 10 characterized in that the frame member has a plurality of bores or further cutouts (83, 83', 84, 84') for holding respective sheaths of the control wires (37, 37', 38, 38'). A deflection control mechanism according to any one of the preceding claims, characterized in that the support structure further comprises a cage structure in which the drive wheel is rotationally supported, and a housing (45) and/or a handpiece body (40) connected to the cage structure, wherein the Housing (45) and / or the handpiece body (40) are rigidly connected to the base plate. A steerable flexible endoscope having an elongate flexible shaft (30) comprising a steerable portion (31) deflectable by movement of at least one pair of opposing steering wires (37, 37', 38, 38'), further comprising a deflection control mechanism ( 29) according to any one of the preceding claims. A set of endoscope assemblies comprising at least first and second elongate flexible shafts (30), each elongate flexible shaft (30) including a steerable portion (31) operable by movement of at least one pair of opposing control wires (37, 37', 38 , 38') being deflectable, said first and second elongate shafts (30) having different allowable ranges of longitudinal movement of said control wires (37, 37', 38, 38'), said endoscope assembly set further comprising a deflection control mechanism (29) adapted for Control of the deflection of the steerable portion (31) of the first elongate flexible shaft (30) is carried out, wherein the deflection control mechanism (29) according to any one of Claims 1 - 12 is configured wherein the deflection control mechanism (29) comprises a first base plate supporting a fixed stop attached to an allowable range of motion of the at least one pair of opposing control wires (37, 37', 38, 38') of the first elongate shaft (30) wherein the endoscope assembly set further comprises a second base plate supporting a fixed stop adapted to an allowable range of motion of the at least one pair of opposing control wires (37, 37', 38, 38') of the second elongate shaft (30). wherein the first base plate is interchangeable with the second base plate to adapt the deflection control mechanism (29) to control the deflection of the steerable portion (31) of the second elongate flexible shaft (30). A method of assembling a flexible endoscope (10), the flexible endoscope (10) having an elongate flexible shaft (30) including a steerable portion (31) operable by movement of at least one pair of opposing control wires (37, 37', 38, 38') being deflectable, the elongate flexible shaft (30) being provided, a deflection control mechanism (29) being provided, the deflection control mechanism (29) being according to any one of Claims 1 - 12 is configured wherein the base plate supports a fixed stop adapted to an allowable range of motion of the at least one pair of opposing control wires (37, 37', 38, 38') of the elongate shaft (30), and the deflection control mechanism (29) having connected to a proximal end of the elongate flexible shaft (30).

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