DE102020118043A1 - Deflection control mechanism for a steerable flexible endoscope, steerable flexible endoscope and method of controlling 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) which comprises a steerable section (31) which, by moving at least one long elongate control element, the deflection control mechanism (29) comprising a support structure, a drive wheel rotatably supported in or on the support structure, and a hand wheel (22, 23), the deflection control mechanism being connectable to the at least one elongate control element in order to cause movement of the at least one elongate control element by rotation of the drive wheel. The deflection control mechanism (29) further includes a first cylindrical member rotationally coupled to the drive wheel and a second cylindrical member rotationally coupled to the support structure, the first and second cylindrical members being arranged to form a substantially annular gap (107). wherein the gap (107) includes at least a pair of opposed wedge portions (115, 115', 116, 116'), at least a pair of clamping members being disposed in the gap (107), each clamping member being biased to engage in a respective of the wedge sections (115, 115', 116, 116'), and wherein at least one unlocking element coupled to the hand wheel (22, 23) is provided for releasing a respective one of the clamping elements. The invention also relates to a steerable flexible endoscope (10) and a method for controlling a flexible endoscope (10).

Description

The present invention relates to a deflection control mechanism for a steerable flexible endoscope, a steerable flexible endoscope with such a deflection control mechanism and a method for controlling 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.

It is often desirable to maintain a specific deflection angle of the steerable portion, for example, to view or manipulate a specific area of the cavity. Such a deflected or flexed condition of the steerable portion can most preferably be maintained without requiring the user to hold the one or more handwheels, allowing the user to operate other controls or instruments with both hands. The deflected state must be maintained against external forces exerted on the shaft by contact with the walls of the cavity and/or against internal forces, for example due to the elasticity of the steerable portion. When the user releases the one or more handwheels, the steerable portion may undesirably change its deflection angle due to these external or internal forces. Therefore, steerable endoscopes have been provided that have a deflection control mechanism that includes a holding or "braking" mechanism to block unwanted movement of the control wires and thus hold the steerable portion of the endoscope shaft at a given articulation or maintain a given deflection angle .

From the US application U.S. 2007/0255104 A1 discloses a mechanism for maintaining a flexed state for an endoscope having a control portion and an insertion portion extending therefrom, the insertion portion having a flexible portion at a distal end thereof, including a flexible portion control mechanism provided on the control portion. At least two members are provided which provide frictional resistance and rotate relative to one another upon actuation of the flexible section control mechanism to provide frictional resistance to maintain the flexible section in any operative position.

According to the EP 3 184 026 A1 For example, in an angle adjusting mechanism for an endoscope, an outer conical surface coaxially aligned with a rotating shaft is provided on an outer surface of the rotary shaft, and a conical cylinder mating with the outer conical surface is fitted onto the outer conical surface. A spring capable of driving the rotary shaft to move in a direction of the tapered cylinder and urging the inner tapered surface to closely abut the outer tapered surface is arranged along an axial direction of the rotary shaft . An inner end of a steel wire for adjusting the angle of the endoscope is fixed to the rotating shaft, and the rotating handle is connected to the rotating shaft.

Known friction-type braking mechanisms, however, are often prone to wear and require time-consuming adjustment or readjustment. In addition, slipping cannot always be safely avoided. In particular, even when the brake is applied, the user may be able to rotate the one or more handwheels and change the flexion angle through increased effort, thereby increasing wear and risk of endoscope failure. Even in a non-actuated state, it is also necessary for a user to exert a comparatively high force on the handwheels in many known braking mechanisms in order to articulate the steerable section.

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, it is an object of the invention to provide a deflection control mechanism that includes a braking or holding mechanism that is less prone to wear, requires less frequent adjustment, and/or allows easier handling with less force to articulate the steerable portion. Further objects of the invention are to provide a steerable flexible endoscope with an improved deflection control mechanism and an improved method for controlling 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 and by a method according to claim 14. 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 deflection 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 optical or electronic Funds are transferred to the handpiece. 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 shaft of the flexible endoscope is deflectable by longitudinal movement of at least one elongate control element, such as a control wire or a pair of counteracting control wires. The steerable portion may have a support structure of, for example, pivoting or elastic elements that can be angled or bent in response to a longitudinal force or bending moment exerted by the at least one control element. Conventionally, to control deflection in one direction and in an opposite direction, two elongate control elements are provided, embodied as a pair of opposing control wires disposed 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. The at least one control element, for example the control wires, can be routed in the shaft to the proximal end of the shaft, thereby being operable in an opposite or counteracting manner such that the deflection control mechanism is connectable to the proximal end of the shaft.

The deflection control mechanism includes a support structure, a drive wheel, and a hand wheel. The support structure can be, for example, a base structure of a handpiece or can be connected to the base structure or to a housing of the handpiece. 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 deflection control mechanism is connectable to the at least one elongate control element to effect movement of the at least one elongate control element by rotation of the drive wheel. In particular, an elongate pulling element can be wound around the drive wheel, with the elongate pulling element having at least one coupling section for coupling to a proximal end of the at least one control element, so that the at least one control element can be moved in its longitudinal direction by rotating the drive wheel in order to to control the deflection of the steerable section. The pull member preferably includes at both ends thereof a coupling portion for coupling to respective proximal ends of each of a pair of opposing control wires. An axis of rotation of the drive wheel preferably runs transversely to a longitudinal direction of the at least one control element.

The hand wheel is rotationally coupled to the drive wheel as described below so that the drive wheel can be rotated by turning the hand wheel. Thus, by manually turning the handwheel, the angle of deflection of the steerable portion of the shaft can be controlled. The handwheel is preferably arranged coaxially with the drive wheel and is supported in or on the support structure. For ease of operation, the hand wheel may include projections, recesses and/or grooves on its outer periphery.

The deflection control mechanism further includes a first cylindrical member rotationally coupled to the drive wheel and a second cylindrical member rotationally coupled to the support structure. Therefore, with respect to the support structure, the first cylindrical member is rotatable and the second cylindrical member is non-rotatable. The second cylindrical member may be fixed to the support structure or may be axially moveable but non-rotatably mounted. The first and second cylindrical members are arranged to form a substantially annular gap between the first and second cylindrical members. For example, the substantially annular gap may be formed between an outer peripheral surface of the first cylindrical member and an inner surface of the second cylindrical member, or vice versa.

The substantially annular gap includes at least a pair of opposed wedge sections. Each wedge section has a narrow end and a wide end, with the narrow end having a reduced radial width compared to the wide end. The width preferably decreases gradually or smoothly from the wide end to the narrow end with both of the spline portions of the at least one pair being oppositely arranged as viewed in a circumferential direction. Preferably, both wedge portions of the at least one pair are arranged with their narrow ends adjacent to each other.

The deflection control mechanism further includes at least a pair of clamp members disposed in the gap, each clamp member being biased to be clamped in a respective one of the wedge portions. In particular, each clamping member is biased and adapted to be clamped in a respective wedge portion upon rotation of the first cylindrical member and hence rotation of the drive wheel. Each of the pair of clamping members may be associated with one of the wedge portions of the at least one pair of wedge portions and biased toward the narrow end of the respective wedge portion; for example, the clamping element can be spring-loaded towards the narrow end of the wedge section. In particular, the wedge sections and the clamping elements are designed such that upon rotation of the first cylindrical element with respect to the second cylindrical element in a first direction, one of the pair of clamping elements is clamped in the respective wedge section, and upon rotation of the first cylindrical element with respect to the second cylindrical element in an opposite direction the other of the pair of clamping members is clamped in the other of the pair of wedge portions. When one of the clamping elements is clamped in a respective wedge section, further relative rotation in a respective direction is prevented.

In addition, at least one unlocking element is provided which is rotatably coupled to the hand wheel and which is arranged to release a respective one of the clamping elements by turning the hand wheel. The at least one unlocking member may be arranged to release a first of the clamping members by rotating the hand wheel in a first direction and to release the other of the pair of clamping members by rotating the hand wheel in an opposite direction. In particular, when the handwheel is turned, a respective clamping element is pushed by the unlocking element towards the wide end of the respective wedge section and is thus pushed out of its clamping position and can even be pushed out of the respective wedge section into an adjacent section of the annular gap. Turning the handwheel in one direction can therefore release a respective one of the pair of clamping members, allowing relative rotation of the first with respect to the second cylindrical member in the respective direction, while turning the handwheel in an opposite direction allows relative rotation of the first and second cylindrical Elements is enabled in the respective opposite direction. Thus, when the first cylindrical member is locked by clamping at least one clamping member as described, it can be unlocked by rotating the drive wheel.

The deflection control mechanism may include other elements such as a fixed or adjustable stop for limiting an allowable range of movement of the at least one control element. The deflection control mechanism may be configured to effect movement of more than one pair of opposing control wires. 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 deflection control mechanism comprises a rotatable first and a non-rotatable second cylindrical member arranged substantially coaxially and forming a substantially annular gap, and at least a pair of clamping members are arranged in the gap for clamping in respective wedge-shaped portions of the gap being clamped, the movement of the at least one control element can be blocked so that the steerable section is held in a given articulation. Thus, the user no longer needs to hold the hand wheel to maintain distraction and can use both hands to operate other controls or instruments. Because at least one unlocking element coupled to the hand wheel is arranged to push a clamping element out of its clamping position, the deflection control mechanism can easily be unlocked and control of the steerable portion resumed by rotating the hand wheel. The deflection control mechanism can allow locking with high braking force with little wear and no need for adjustment. Further, the mechanism can have low friction and be easy to use.

In particular, by coupling the hand wheel to the drive wheel as described, both locking and unlocking of the deflection control mechanism can be achieved in an automatic two-way self-locking manner. In this sense, the deflection control mechanism includes a braking mechanism. When, due to external or internal forces acting on the steerable portion, torque is applied to the drive wheel in a first direction by the at least one elongate control element, rotation of the drive wheel is automatically blocked by locking the first cylindrical element attached to the Drive wheel is rotatably coupled, is blocked, whereby the blocking is achieved by clamping a respective one of the at least one pair of clamping elements in a respective wedge portion of the gap. On the other hand, if a torque is applied to the Applying the handwheel in the first direction pushes the respective clamping member out of its clamping position in the respective wedge section, releasing the clamping member and allowing rotation of the first cylindrical member and the drive wheel. Accordingly, when torque is applied to the impeller in the opposite direction by the at least one elongate control element, rotation of the impeller is blocked by clamping the other of the at least one pair of clamping members in the other wedge portion of at least one pair of wedge portions. By exerting a torque on the hand wheel in the same direction, the respective clamping element is released, whereby the brake is unlocked. The brake mechanism designed as described can allow a particularly easy and intuitive actuation by a user.

According to a preferred embodiment of the invention, the first cylindrical member is substantially disc-shaped and the second cylindrical member is substantially drum-shaped, wherein the gap is formed between an outer peripheral surface of the first cylindrical member and an inner surface of the second cylindrical member. Thus, with respect to the axis of rotation of the first cylindrical member and viewed in the radial direction, the substantially drum-shaped second cylindrical member encloses the first cylindrical member, with a radially extending space between the outer peripheral surface of the first cylindrical member and a corresponding inner surface of the second cylindrical Elements is essentially annular and forms a gap in which the at least one pair of clamping elements is arranged. In this way, a brake mechanism with a particularly simple design can be provided.

The first cylindrical element preferably has a radial ridge or hump which has at least one lateral wing forming a wedge surface, the lateral wing having an inclination determined such that upon rotation of the first cylindrical member is clamped with respect to the second cylindrical member between the outer peripheral surface of the first cylindrical member and the inner surface of the second cylindrical member. The wedge surface and a corresponding portion of the inner surface of the second cylindrical member form a wedge portion of the gap. The radial ridge, viewed circumferentially, most preferably also has an inclined wing on its other side, the wing being similarly inclined so that the other of the pair of clamping members is clamped upon rotation of the first cylindrical member in the opposite direction. According to this embodiment, the outer peripheral surface of the first cylindrical member and the inner surface of the second cylindrical member may be part-cylindrical surfaces substantially coaxial with each other and the axis of rotation of the first cylindrical member, but with the outer peripheral surface of the first cylindrical member being at least one elevated has a portion which protrudes in a radial direction beyond the cylindrical surface and has inclined wedge surfaces on its side wings forming the opposed wedge portions of the gap. In view of friction between the clamping elements and the respective surfaces of the first and second cylindrical elements, the angle of inclination with respect to a cylindrical surface of the side wings can be chosen so that at least one clamping element automatically comes into a clamping position in a respective wedge section and so between the first and the second cylindrical member is clamped when the first cylindrical member is rotated with respect to the second cylindrical member. In this way further rotation of the first relative to the second cylindrical member is prevented, thereby achieving self-locking in a safe and simple manner.

Advantageously, the gap comprises two pairs of opposite wedge portions, which are diametrically opposed to each other as seen with respect to the axis of rotation of the first cylindrical element, two pairs of clamping elements and two unlocking elements, each clamping element being biased to be clamped in a respective one of the wedge portions, and wherein each unlocking element is coupled to the handwheel to release a respective one of the clamping elements. In particular, the outer peripheral surface of the first cylindrical member may have two diametrically opposed ridges, each ridge having inclined side wings on both sides, the inclined side wings forming the wedge portions. The two opposed wedge portions of each pair are arranged with their narrow ends directed towards a respective unlocking element so that the clamping elements can be pushed out of a clamping position in a respective wedge portion by action of the respective unlocking element. In this way, rigidity and reliability of the brake mechanism can be increased.

Each clamping element is preferably designed as a substantially cylindrical roller. In particular, a diameter of the rollers can be chosen to be less than a radial width of the gap at the wide end of each Wedge portion and is greater than a radial width of the gap at the narrow end of each wedge portion. Materials and surface structures of the rollers and the surfaces of the first and second cylindrical members forming the wedge portions can be selected so that, taking into account the inclination of the respective wedge surfaces in the wedge portions, one of the two rollers of each pair of clamping members by rotation of the first cylindrical member with respect to the second in a first direction in the wedge section and the other of the two rollers of each pair of clamping members is clamped by rotation of the first cylindrical member with respect to the second in an opposite direction in the opposite wedge section of the respective pair of wedge sections. Due to the fact that the clamping elements are designed as substantially cylindrical rollers, the friction when operating the deflection control mechanism can be reduced.

According to a preferred embodiment of the invention, the at least one unlocking element engages the first cylindrical element to rotate the first cylindrical element. Thus, since the unlocking member is rotatably coupled to the hand wheel, the first cylindrical member can be rotated by turning the hand wheel. The at least one unlocking element is preferably designed as a coupling pin or bolt which is rigidly coupled to the handwheel or at least rotationally coupled thereto, the coupling pin engaging with a recess, a slot or a bore of the first cylindrical element, so that the coupling pin at Rotation of the hand wheel contacts the first cylindrical member in the recess, slot or bore to rotate. If the first cylindrical member is substantially disc-shaped, the recess, slot or bore may be provided in a collar axially offset from a disc portion of the first cylindrical member, with an outer peripheral surface of the disc portion forming an inside of the substantially annular gap. In particular, the unlocking element can be considered as a claw that transmits the rotation of the handwheel to the first cylindrical element. Preferably both or all of the unlocking elements are configured as coupling pins or bolts, each engaging in a respective recess, slot or bore of the first cylindrical element. Thus, the operation of the deflection control mechanism can be further simplified, with the drive wheel being rotatable by manually rotating the handwheel.

Most preferably, the at least one unlocking element engages the first cylindrical element with sufficient play such that rotation of the hand wheel releases a respective clamping element from its clamping position in the respective wedge section before the unlocking element rotates the first cylindrical element. In particular, the unlocking element can engage in an elongate recess or slot of the first cylindrical element, which extends in a circumferential direction, providing angular clearance so that the unlocking element contacts the first cylindrical element only then when a corresponding angle of rotation of the hand wheel exceeds the angular play, which angle of rotation is sufficient to release the clamping element from its clamping position in the wedge section. The clamping member may be spring loaded towards the narrow end of the respective wedge portion, with a spring force or tension selected sufficient to bias the clamping member to clamp into the wedge portion but low enough to release the clamping member as described. The spring force can thus be selected, for example, so that a torque to be applied to the handwheel to release the clamping element is less than or approximately equal to a normal torque required to hold the steerable section at a given deflection angle. In this way, the operation of the deflection control mechanism can be facilitated as it is simple and intuitive.

According to a particularly advantageous embodiment, the gap comprises two pairs of opposing wedge sections, two pairs of clamping elements and two unlocking elements, a compression spring being arranged in the gap and extending between two circumferentially adjacent or consecutive clamping elements. This means that two helical compression springs are provided, for example, which are each arranged between a clamping element of a first pair and a subsequent clamping element of the second pair of clamping elements. Such an arrangement makes it possible in a particularly simple manner to provide a suitable spring force for pretensioning each clamping element towards a narrow end of a respective wedge section.

According to a preferred embodiment of the invention, an unlocking tab is provided between the at least one unlocking element and each of the at least one pair of clamping elements, which tab contacts the unlocking element and the respective clamping element. That is, on both sides of the unlocking element in a circumferential direction, a respective unlocking tab is arranged, which the unlocking element ment and the respective clamping element contacted, wherein the clamping element is biased towards the narrow end of the respective wedge section and is thus biased towards the respective unlocking tab. In particular, each of the two clamping elements can be spring-loaded in order to contact the respective unlocking tab, and furthermore the unlocking tab contacts the unlocking element due to the spring tension. Due to the fact that the unlocking tabs are arranged between the unlocking element and the clamping elements, the friction can be further reduced and the unlocking of the brake can be facilitated.

According to a particularly advantageous embodiment of the invention, each unlocking tab has a spreading surface which is designed to interact with a corresponding spreading surface of the at least one unlocking element in order to move a respective clamping element out of its clamping position when the unlocking tab is displaced in a substantially axial direction with respect to the respective unlocking element in the respective spline section with the axial direction being parallel to the axis of rotation of the first cylindrical member. Thus, when the release tab is pushed in an axial direction, the spreading surfaces of the release tab and a respective release member contacting the release tab cooperate such that the clamping member is moved in a circumferential direction relative to the release member and thus is pushed out of its clamping position. In particular, the clamping element can be held in such a circumferential position by the interaction of the spreading surfaces that it cannot reach its clamping position regardless of the actuation of the hand wheel and regardless of a position of the unlocking element in the recess, the slot or the bore of the first cylindrical element. The brake of the deflection control mechanism can therefore be deactivated by axially displacing the release tabs. Conversely, by shifting the release tabs in an opposite axial direction, the brake can be reactivated and act in an automatic self-locking manner as described above. When the brake is deactivated, the steerable portion of the endoscope shaft is able to flex freely and therefore conform to a shape of a lumen or access pathway into which the shaft has been inserted. Deactivation of the brake thus facilitates retraction of the endoscope shaft from the cavity or access route. Because of the configuration of the brake mechanism described, the force required to articulate the steerable portion can be the same whether the brake is engaged or disengaged, thereby facilitating operation of the endoscope.

Further advantageously, the at least one unlocking element protrudes into the gap in the axial direction, and the unlocking tabs and the second cylindrical element are displaceable in the axial direction with respect to the unlocking element. The at least one unlocking element can be rigidly connected to a base plate of the handwheel, which is axially fixed. The release tabs are preferably trapped between the first and second cylindrical members, the first and second cylindrical members being slidable together in the axial direction, with an axial spring being provided for reset. Most preferably, the clamping members are also trapped between the first and second cylindrical members and are axially slidable by sliding the first and second cylindrical members as described. The brake can thus be activated or deactivated by axially displacing the second cylindrical element or the first and the second cylindrical element. In particular, the second cylindrical member may be arranged to be non-rotatable with respect to the support structure but guided to be movable in the axial direction, and the first cylindrical member is rotationally coupled to the drive wheel but guided to be is slidable in the axial direction. If the first cylindrical member is substantially disk-shaped and the second cylindrical member is substantially drum-shaped, with the gap formed between an outer peripheral surface of the first cylindrical member and an inner surface of the second cylindrical member, the unlocking tabs may be in a radial position toward the inside of the Be arranged inner surface of the drum-shaped second cylindrical member. The activation and deactivation of the brake can be made possible by a simple and robust design. For manual activation and deactivation of the brake, a brake activation element or "brake switch" such as a button or lever may be provided on the handpiece to cause axial displacement of the release tabs with respect to the release elements as described.

According to a preferred embodiment of the invention, the deflection control mechanism comprises a further drive wheel which is rotatably supported in or on the support structure and is preferably coaxial with the aforesaid drive wheel, and a further handwheel which may be arranged coaxially with the aforesaid handwheel. According to this embodiment, the deflection control mechanism also includes a wei a further first cylindrical member rotatably coupled to the further drive wheel and a further second cylindrical member rotationally coupled to the support structure, the further first and second cylindrical members being arranged to form a further substantially annular gap, the further substantially annular gap being at least another pair of opposing wedge sections. There is also provided at least one further pair of clamping members disposed in the further gap, each of the further pair of clamping members being biased to clamp in a respective one of the further wedge portions, and at least one further unlocking member operable to release a respective one of the further pair Clamping elements is coupled to the other handwheel. The further drive wheel, the further handwheel, the further first and second cylindrical element, the further clamping elements and the further unlocking element can be designed like the corresponding elements described above. In particular, it can be said that the deflection control mechanism according to the present embodiment comprises, in addition to the elements of the deflection control mechanism according to any of the previously described embodiments, further elements constituting a further deflection control mechanism and having a common support structure, the further deflection control mechanism also being provided with a braking mechanism. The deflection control mechanism may be configured to control the deflection of the steerable portion of an endoscope shaft comprising at least two elongate control elements for controlling the deflection of the steerable portion in two different planes, with at least a first elongate control element being actuated by turning the handwheel as described above to control deflection in a first plane, and at least a second elongate control element actuated by turning the further handwheel to control deflection in a second plane. The steerable section can be held at a given deflection angle in the first and/or second plane by the braking mechanism associated with the handwheel and/or the further handwheel. The first and second planes can be at an angle of 90° to one another. Thus, the steerable portion can be deflected and held in any direction.

According to a further aspect of the invention, a deflection control mechanism is provided for a steerable flexible endoscope, the endoscope having an elongate flexible shaft comprising a steerable portion which is deflectable by longitudinal movement of at least one elongate control element, the deflection control mechanism comprising a support structure, a a drive wheel rotatably supported in or on the support structure and a hand wheel and wherein the deflection control mechanism is connectable to the at least one elongate control element to effect movement of the at least one elongate control element by rotation of the drive wheel. The axis of rotation of the hand wheel may be transverse to a longitudinal direction of the at least one elongate control element and is preferably coaxial to an axis of rotation of the drive wheel. According to this aspect of the invention, the drive wheel is rotatably coupled to the hand wheel by a two-way self-locking brake mechanism such that the drive wheel is locked when torque is applied to the drive wheel by the at least one control element and the drive wheel is unlocked when rotation of the Handwheel torque is applied to the handwheel. In particular, the braking mechanism can be designed as described above. A deflection control mechanism can thus be provided which allows a particularly easy and intuitive actuation of a flexible endoscope equipped with the deflection control mechanism.

According to a further aspect of the present invention there is provided a steerable flexible endoscope having an elongate flexible shaft comprising a steerable portion which is deflectable or bendable by longitudinal movement of at least one elongate control element, the flexible endoscope further comprising a deflection control mechanism, which is designed as described above. In particular, the endoscope may include a handpiece connected to a proximal end of the flexible shaft, the handpiece receiving the deflection control mechanism, the proximal end of the at least one elongate control element being secured in a fastener of the deflection control mechanism. Most preferably, the steerable portion is deflectable by movement of at least two elongate control members in two perpendicular planes, and the deflection control mechanism is configured to operate the at least two elongate control members to control deflection in the two perpendicular planes as described above.

The present invention further relates to a method of controlling a flexible endoscope, the flexible endoscope having an elongate flexible shaft comprising a steerable portion operable by movement of at least one elongate control element, for example by longitudinal movement of at least one pair of control wires, is deflectable and wherein the flexible endoscope comprises a deflection control mechanism for controlling the movement of the at least one elongate control element, the deflection control mechanism being configured as described above. According to the method, the steerable portion is deflected by turning the hand wheel, the steerable portion being automatically maintained at the deflection angle achieved by clamping the at least one pair of clamping members in a respective wedge portion of the substantially annular gap. Further according to the method, the steerable portion can be unlocked and further deflected or straightened by turning the handwheel again in a corresponding direction. The procedure ensures a particularly safe and practical operation of the flexible endoscope.

The deflection control mechanism may include other features such as a stop mechanism as is 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), and/or a modular panel structure as known from co-pending patent application "..." (internal file number ...), both filed by the same applicant on the same date as the present application and hereby incorporated by reference registration are included.

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 einen proximalen Teil des Ablenksteuerungsmechanismus von 2, in einer vergrößerten, vertikalen Längsschnittansicht;
• 4 zeigt eine Querschnittsansicht des Bremsmechanismus in Bezug auf das erste Handrad des Ablenksteuerungsmechanismus von 2;
• 5 zeigt Elemente des Bremsmechanismus des ersten Handrads des Ausführungsbeispiels in einer Perspektivansicht teilweise in Durchsicht;
• 6a und 6b zeigen den beispielhaften Bremsmechanismus des ersten Handrads in einer anderen Schnittansicht in einem deaktivierten Zustand (6a) und in einem aktivierten Zustand (6b);
• 7a und 7b zeigen den beispielhaften Bremsmechanismus des ersten Handrads in einer weiteren Schnittansicht in dem deaktivierten Zustand (7a) und in dem aktivierten Zustand (7b);
• 8a und 8b zeigen den beispielhaften Bremsmechanismus des ersten Handrads in einer Perspektivansicht teilweise in Durchsicht in dem deaktivierten Zustand (8a) und in dem aktivierten Zustand (8b).

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 12 shows a proximal portion of the deflection control mechanism of FIG 2 , in an enlarged vertical longitudinal sectional view;
• 4 FIG. 12 shows a cross-sectional view of the braking mechanism in relation to the first handwheel of the deflection control mechanism of FIG 2 ;
• 5 12 shows elements of the braking mechanism of the first hand wheel of the embodiment in a perspective view, partly in phantom;
• 6a and 6b show the example brake mechanism of the first hand wheel in another sectional view in a deactivated state ( 6a ) and in an activated state ( 6b );
• 7a and 7b show the exemplary brake mechanism of the first hand wheel in a further sectional view in the deactivated state ( 7a ) and in the activated state ( 7b );
• 8a and 8b 12 shows the exemplary braking mechanism of the first handwheel in a partially phantom perspective view in the deactivated state ( 8a ) and in the activated state ( 8b ).

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. Between the housing 21 and the first handwheel 22 is arranged a brake lever 42 for actuating a deflection brake in relation to the first handwheel 22 (see below, in 1 Not shown). 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 includes a steerable portion 31. The steerable Bare portion 31 may form a distal end portion of shaft 30 or, as in 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 portion 31, on the other hand, can be actively flexed by turning the handwheels 22,23. 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, a deflection angle being controllable by turning the first handwheel 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 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 43 defines a common axis of rotation of two drive wheels (pinions 69, 59) which can be turned by turning the first and second hand wheels 22, 23, respectively, as described in more detail below.

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 may also be 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 elements which cooperate with corresponding fixed stops (not shown). The mounting blocks 52, 52' and the stop blocks 56, 56' each have a substantially rectangular cross-section and can be guided in correspondingly shaped channels. 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 configured to control the 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 is visible in the figures). The lower tier 60 is configured in a similar manner as described above (only attachment block 62, stop block 66 and chain 68 are shown in Fig 2 1) 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. FIG. Both layers 50, 60 comprise elements of a support structure and are stacked one on top of the other, being mounted on an upper side of the body 40. FIG. 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 12 shows the proximal end portion of the deflection control mechanism 29 in a vertical longitudinal cross section. How out 3 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 second handwheel 23 will. Similarly, a pinion 69 of the lower tier 60 of the deflection control mechanism is mounted on a further pivot shaft 47 which extends coaxially with the pivot shaft 46 into the first hand wheel 22 to which it is connected, to be rotated by the first hand wheel 22 is rotated. The linkage shaft 46 and hence the pinion 59 of the upper tier 50 of the deflection control mechanism 29 are 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 tier 60 is supported by a ball bearing 49 in a cage body 44a fixedly connected to the cage 44. As shown in FIG.

How further in 3 As shown, the top tier 50 of the deflection control mechanism comprises an assembly of plates 70, 71, 72 stacked one on top of the other. A top plate 45 of a half-shell housing 45 is arranged on the top plate 70 . The lower layer 60 is separated from the upper layer 50 by a thin metal sheet 75 and comprises further plates 76, 77 which are also stacked on top of one another. The stacked plates 70, 71, 72, 75, 76, 77 are fixed to each other by a vertical bolt 73 and including the housing 45 by a screw 74 and are fixed to a raised portion of the handpiece body 40 by the bolt 73 and the screw 74. The cage 44 and cage body 44a are fixedly held to the body 40 by a screw 44b and form a rigid support structure including the cage and cage body 44,44a, axle 43, stack of plates 70,71,72,75,76 , 77, and of the body 40.

The deflection control mechanism includes a brake mechanism, which is in the lower part of 3 is shown in section view drawn in a plane including the axis of rotation 100 of the pinions 59,69 and the corresponding articulation shafts 46,47. In the following description, the term "axial" refers to the common axis of rotation 100 of the pinions 59, 69 and the linkage shafts 46, 47.

The braking mechanism relating to the first handwheel 22, ie, the lower layer 60 and the lower pair of control wires 38, includes a brake lever 42 fixedly mounted on a brake lever shaft 101 pivotally supported at a lower portion of the cage body 44a. An approximately circular cam 102 is rigidly coupled to the brake lever shaft 101 and thus rotationally coupled to the brake lever 42 . Adjacent to and parallel to the cam disk 102, a brake drum 103 is non-rotatably but axially movably supported on the lower portion of the cage body 44a. Further in the downward axial direction and abutting the brake drum 103 is a wedge washer 104 rotatably coupled to the linkage shaft 47 of the pinion gear 49 of the lower tier 60 , the wedge washer 104 thus being rotatably coupled to the pinion gear 49 is. On the other hand, the wedge disk 104 is axially movable with respect to the linkage shaft 47 . A gap 107 is formed between an outer peripheral surface 105 of wedge disk 104 and an inner surface 106 of brake drum 103 , gap 107 being essentially ring-shaped and approximately symmetrical with respect to axis of rotation 100 of wedge disk 104 . The outer peripheral surface 105 of the wedge washer 104 and the inner surface 106 of the brake drum 103 are both substantially cylindrical, so that the wedge washer 104 and the brake drum 103 form the aforementioned first and second cylindrical members in the embodiment shown.

The brake mechanism also includes a handwheel base plate 110 on which the first handwheel 22 is fixedly mounted. The handwheel base plate 110 is rotatably mounted on the pivot shaft 47 and is also rotatable with respect to the support structure and has an axis of rotation 100. The handwheel base plate 110 is secured against axial displacement in the downward direction by abutments 111.

Two coupling pins 112, 112' are fastened in respective bores of the hand wheel base plate 110 and extend in an upward direction into the gap 107. The wedge disk 104 is supported on the hand wheel base plate 110 in the downward axial direction via a multi-wave compression spring 113.

4 shows the braking mechanism of the first handwheel 22 in a cross-sectional view in the plane of the inner portion of the wedge disk 104, perpendicular to the axis of rotation 100. The wedge disk 104 has a substantially square cutout 114, with which a correspondingly designed section of the linkage shaft 47 engages, so that the wedge disk 104 is rotatably coupled but held axially displaceably on the articulation shaft 47 . The essentially annular gap 107 is formed between the outer surface 105 of the wedge washer 104 and the inner surface 106 of the brake drum 103 . Since the outer peripheral surface 105 of the wedge washer 104 has inclined portions that make an angle other than 90° with a radial direction, the gap 107 includes wedge portions 115, 115', 116, 116' each having a wide end and a narrow end. The wedge portions 115, 115', 116, 116' are arranged diametrically opposite each other in two pairs, with the respective narrow ends of the wedge portions of each pair facing each other. In the embodiment shown, the wedge portions 115, 115', 116, 116' are formed between the inner cylindrical surface 106 of the brake drum 103 and the wedge surfaces formed by the inclined side wings of the radial ridges on the outer peripheral surface 105 of the wedge disc 104.

How out 4 As can be seen, the coupling pin 112 projects into the gap 107 in a portion of the gap 107 that extends between the narrow ends of a pair of wedge sections 115, 116, and the other coupling pin 112' projects into the gap 107 in a portion that extends between the narrow ends of the other pair of wedge portions 115', 116'. A substantially cylindrical locking roller 117, 117', 118, 118' is located in each of the wedge sections 115, 115', 116, 116', and between each locking roller 117, 117', 118, 118' and a respective coupling pin 112, 112 'A release tab 119, 119', 120, 120' is provided with a substantially rectangular cross-section. Further, helical locking springs 121, 121' are provided in portions of the gap 107 extending between the wide ends of the wedge portions 115, 115', 116, 116', whereby each locking roller 117, 117', 118, 118' toward the narrow end of the respective wedge section 115, 115', 116, 116' is spring-loaded. Locking springs 121, 121', wedge disk 104, brake drum 103 and locking rollers 117, 117', 118, 118' are designed in such a way that they prevent clamping of the locking rollers 117, 117', 118, 118' in the respective wedge sections 115, 115', 116, 116' as described below. In particular, the biasing force exerted by the springs 121, 121', the inclination of the respective wedge surfaces of the wedge sections 115, 115', 116, 116' and the materials and surface structures of the wedge disk 104, the brake drum 103 and the locking rollers 117, 117', 118 , 118' are chosen accordingly.

5 12 shows the brake mechanism of the first hand wheel 22 in a perspective view, partly in see-through, as seen from the downward side (refer to FIG 2 and 3 ), wherein the second hand wheel 23 and internal elements of the second hand wheel 23 have been omitted. The handwheel base plate 110 of the first handwheel 22 is shown in phantom. How out 5 As can be seen, wedge washer 104 includes a collar 125 disposed at a downwardly extending edge of its outer peripheral surface 105. As shown in FIG. The collar 125 extends in a radial direction and has an outer radius that is slightly smaller than the radius of the inner surface 106 of the brake drum 103 . The collar 125 has a multiplicity of recesses. Coupling pins 112, 112' project from handwheel base plate 110 (which is in front of collar 125 in the illustration of Figs 5 located) into gap 107 (located behind collar 125) through recesses 126 and 126', respectively. The coupling pins 112, 112' engage the collar 125 in the respective recesses 126, 126'. with some play in the circumferential direction.

• Wenn eine äußere Kraft auf den lenkbaren Abschnitt 31 des Endoskopschafts 30 wirkt, wird eine Kraft auf mindestens eines der Paare Steuerungsdrähte 37, 37', 38, ausgeübt, die wirken, um ein Drehmoment auf ein entsprechendes der Ritzel 59, 69 auszuüben (siehe 1 - 3). Im Folgenden wird die Wirkung des Bremsmechanismus in Bezug auf das erste Handrad 22 erläutert, wobei davon ausgegangen wird, dass die äußere Kraft in einer Ebene wirkt, die einer durch das erste Handrad 22 und die Elemente der unteren Lage 60 gesteuerten Ablenkung entspricht. Es versteht sich jedoch, dass das zweite Handrad 23, das sich auf die obere Lage 50 bezieht, mit einem Bremsmechanismus ausgerüstet sein kann, der analog zu dem Bremsmechanismus, der sich auf das erste Handrad 22 bezieht, ausgestaltet ist und analog dazu wirkt.

The action of the braking mechanism as shown in 3 - 5 is as follows:

• When an external force is applied to the steerable portion 31 of the endoscope shaft 30, a force is applied to at least one of the pair of control wires 37, 37', 38, which act to apply torque to a corresponding one of the pinions 59, 69 (see Fig 1 - 3 ). The following explains the action of the braking mechanism with respect to the first handwheel 22, assuming that the external force acts in a plane corresponding to a deflection controlled by the first handwheel 22 and the lower tier elements 60. However, it is understood that the second hand wheel 23 relating to the upper layer 50 can be equipped with a braking mechanism which is designed and acts analogously to the braking mechanism relating to the first hand wheel 22 .

If a torque is applied to the pinion gear 69 due to the external force acting on the steerable portion 31, this torque is transmitted to the wedge plate 104 through the linkage shaft 47 to rotate the wedge plate 104 (see FIG 3 ). Initially, when rotation of wedge disk 104 in a counterclockwise direction as viewed in FIG 4 is considered, the locking roller 117 is pressed into the wedge section 115 by the spring 121 and is clamped between the outer peripheral surface 105 of the wedge disc 104 and the inner surface 106 of the brake drum 103 due to the rotation of the wedge disc 104, thereby further rotating the wedge disc 104 with respect to the Brake drum 103 is blocked. Similarly, locking roller 117' is urged into wedge portion 115' by spring 121' and clamped between wedge disc 104 and brake drum 103. Since the brake drum 103 is rotatably coupled to the cage body 44a, the rotation of the pinion gear 69 is blocked so that the steerable portion 31 is held in a given articulation.

If the wedge washer 104 in 4 rotates clockwise, locking roller 118 is similarly urged into wedge portion 116 by spring 121' and locking roller 118' is urged into wedge portion 116' by spring 121, and each is sandwiched between the outer peripheral surface 105 of wedge washer 104 and the inner surface 106 of the brake drum 103 is clamped.

Further clockwise rotation of wedge disk 104 is therefore also blocked. The mechanism described can therefore be considered as a self-locking two-way braking mechanism.

On the other hand, when the handwheel 22 is rotated, the handwheel base plate 110 rotates correspondingly, moving the link pins 112, 112' circumferentially. If it is initially assumed that the hand wheel 22 in the representation of 4 is rotated counterclockwise, the coupling pin 112 pushes the locking roller 117 out of its clamped position by contacting the unlocking tab 119 and pushing towards the locking roller 117. Similarly, locking roller 117' is released from its pinched position by circumferentially sliding release tab 119' through coupling pin 112'. Similarly, when the handwheel 22 is rotated clockwise, the coupling pin 112 pushes the locking roller 118 out of its clamped position via the release tab 120, and the coupling pin 112' pushes the locking roller 118' out of its clamped position by pushing the release tab 120'. Thus, the brake mechanism is automatically unlocked when the hand wheel is rotated in any direction. The coupling pins 112, 112' not only serve to couple the wedge plate 104 to the handwheel 22 as described above, but also serve as unlocking elements to unlock the brake to release the locking rollers 117, 117', 118, 118'. The spring force exerted by the locking springs 121, 121' is adjusted accordingly to facilitate unlocking.

As in 5 shown, the recesses 126, 126 'in the collar 125 of the wedge disk 104 are further designed so that the coupling pins 112, 112' have sufficient play to the locking rollers 117, 117 ', 118, 118' when rotating the handwheel base plate 110 from their to release the respective clamping positions. When the hand wheel 22 has been rotated through an appropriate angle, the coupling pins 112, 112' contact the wedge washer 104 and transmit torque applied to the hand wheel 22 to the wedge washer 104 and further to the pinion 69 of the lower tier 60 of the deflection control mechanism 29. After Thus, after unlocking the braking mechanism, the steerable section 31 of the endoscope shaft 30 can be controlled by turning the handwheel 22 in the usual way.

Thus, the braking mechanism automatically holds the steerable portion 31 of the endoscope shaft 30 in a given deflected state, and the user no longer has to hold the handwheels 22 . The user therefore has the ability to operate other controls or instruments to observe or perform manipulations. When the user resumes manipulation of the flexible endoscope 10 by turning one of the handwheels 22, 23, the respective brake is automatically released and deflection of the steerable section 31 can be performed as usual.

However, in some applications or in some situations it may be necessary to turn off or disable the braking mechanism. Thus, for example, when the endoscope shaft 30 is to be withdrawn from a lumen into which it has been inserted, it may be advantageous if the steerable portion 31 can orient or flex by contact with a wall of the lumen, or conform to the shape of a curved one Can adjust access route to the cavity. Therefore, according to the described embodiment, the braking mechanism has an activated state and a deactivated state. In the activated state, the braking mechanism functions as described above, while in the deactivated state, there is no self-locking, so that the steerable section 31 can deform under external forces acting on the steerable section 31, unless the user holds the handwheels 22 , 23

Activation and deactivation of the brake mechanism related to the first hand wheel 22 can be controlled by the brake lever 42 (see Fig 3 ) as described below. However, it should be understood that the activation and deactivation of the brake mechanism related to the second handwheel 23 is similar and controllable by the brake knob 24 (see Fig 1 ).

6a and 6b 12 show the braking mechanism in a sectional view in a plane parallel to the axis of rotation 100 of the hand wheel 22 and the wedge disk 104, but offset radially with respect to the axis of rotation 100 and perpendicular to the plane of the sectional view of FIG 3 .

How out 6a and 6b As can be seen, the unlocking tabs 119, 120 have spreading surfaces 129 and 130, respectively, which cooperate with corresponding spreading surfaces 131, 132 of the unlocking pin 112 in order to spread the unlocking tabs 119, 120 with respect to the unlocking pin 112 during axial displacement. Such axial displacement occurs by axial displacement in the downward direction of the brake drum 103 and wedge disk 104, with the release tabs 119, 120 and locking rollers 117, 118 being slidable between the collar 125 of the wedge disk 104 and a top plate 108 of the brake drum 103 are included. By spreading the unlocking tabs 119, 120 as in 6a As shown, the respective locking rollers 117, 118 are pushed away from the narrow ends of the respective wedge portion 115, 116 and held out of their clamping position (see Fig 4 ). Similarly, the release tabs 119', 120' have spreader surfaces which cooperate with corresponding spreader surfaces of the release pin 112' to urge the release tabs 119', 120' out of their respective clamped positions. Irrespective of any rotation of the wedge disk 104 with respect to the brake drum 103, there is therefore no jamming and self-locking is prevented. In this way the braking mechanism can be deactivated. Conversely, when the brake drum 103 and wedge washer 104 return to their original axial positions, as in FIG 6b shown, the springs 120, 120' to restore the arrangement described above (see 3 and 4 ), whereby the brake is thus activated again.

7a and 7b show the axial displacement of the brake drum 103 and the wedge disk 104 in a sectional view in a plane parallel to the axis of rotation 100 and including the axis of rotation 100; 7b is equivalent to 3 . In the disabled state ( 7a ), the brake drum 103 and the wedge washer 104 contacting the brake drum 103 are pressed down against the force of the compression multi-wave spring 113. In the activated state of the brake mechanism ( 7b ) the wedge disk 104 and the brake drum 103 are pushed upwards by the action of the compression spring 113.

The brake lever 42 serves to activate and deactivate the brake, as further described in 8a and 8b shown. By pivoting the lever 42, the brake lever shaft 101 and consequently the cam plate 102 are rotated (see Fig 3 , 7a , 7b ). Cam plate 102 includes a spherical cam member 135 which is inserted into a corresponding recess in cam plate 102 . The cam member 135 cooperates with an inclined notch 136 in the top plate 108 of the brake drum 103 to translate the brake drum 103 in the downward axial direction as the cam plate 102 rotates. The cam plate 102 may include other cam elements and the brake drum 103 may have other notches arranged to prevent tipping. The top plate 108 of the brake drum 103 is also provided with a stopper 137 to limit the pivotal movement of the brake lever 42. As shown in FIG. In an "unbraked" rotational position of the brake lever 142 is thus the brake drum 103 is held in a downward position, avoiding the self-locking action of the brake mechanism ( 8a ), while in a "braked" position of the brake lever 42, the self-locking two-way braking mechanism is activated ( 8b ).

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 FIG 1 - 3 to be shown. 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

41

sealing ring

42

lever

43

axis

44

Cage

44a

cage body

44b

screw

45

half-shell housing

46

wave

47

wave

48

ball-bearing

49

ball-bearing

50

Upper layer

51, 51'

Wire Spool Bracket

52, 52'

block

56, 56'

block

58

Chain

59

pinion

60

lower tier

61, 61'

Wire Spool Bracket

62, 62'

block

66

block

68

Chain

69

pinion

70

plate

71

plate

72

plate

73

bolt

74

screw

75

sheet

76

plate

77

plate

100

axis

101

brake lever shaft

102

cam disk

103

brake drum

104

wedge washer

105

surface

106

surface

107

gap

108

plate

110

hand wheel base plate

111

counter bearing

112, 112'

coupling pin

113

compression spring

114

cutout

115, 115'

wedge section

116, 116'

wedge section

117, 117'

locking roller

118, 118'

locking roller

119, 119'

release tab

120, 120'

release tab

125

Federation

126, 126'

recess

129

spreading surface

130

spreading surface

131

spreading surface

132

spreading surface

135

cam element

136

score

137

attack

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

• US 2007/0255104 A1 [0006]
• EP 3184026 A1 [0007]

Claims (14)

A deflection control mechanism for a steerable flexible endoscope (10), the endoscope (10) having an elongate flexible shaft (30) comprising a steerable portion (31) deflectable by movement of at least one elongate control element, the deflection control mechanism ( 29) a support structure, a drive wheel rotatably supported in or on the support structure, and a handwheel (22, 23), wherein the deflection control mechanism is connectable to the at least one elongate control element to rotate the drive wheel to cause movement of the at least one elongate control element, characterized in that the deflection control mechanism (29) further comprises a first cylindrical member rotatably coupled to the drive wheel and a second cylindrical member rotatably coupled to the support structure, the first and second cylindrical members for forming a substantially annular gap ( 107), the gap (107) comprising at least one pair of opposed wedge portions (115, 115', 116, 116'), at least one pair of clamping elements being arranged in the gap (107), each clamping element being biased to to be clamped in a respective one of the wedge sections (115, 115', 116, 116'), and wherein at least one unlocking element coupled to the handwheel (22, 23) is provided for releasing a respective one of the clamping elements. deflection control mechanism claim 1 , characterized in that the first cylindrical element is substantially disc-shaped and the second cylindrical element is substantially drum-shaped and that the gap (107) is between an outer peripheral surface (105) of the first cylindrical element and an inner surface (106) of the second cylindrical element is formed. deflection control mechanism claim 2 , characterized in that the first cylindrical element has a radial prominence having at least one lateral wing, the lateral wing forming a wedge portion (115, 115', 116, 116'), the lateral wing having such an inclination that a respective clamping element upon rotation of the first cylindrical member with respect to the second cylindrical member being pinched between the outer peripheral surface (105) of the first cylindrical member and the inner surface (106) of the second cylindrical member. A deflection control mechanism according to any one of the preceding claims, characterized in that the gap (107) comprises two pairs of opposed wedge sections (115, 115', 116, 116'), the two pairs of opposed wedge sections (115, 115', 116, 116') facing each other arranged diametrically opposite, two pairs of clamping elements, each clamping element being biased to be clamped in a respective one of the wedge sections (115, 115', 116, 116'), and two unlocking elements which are connected to the hand wheel (22, 23) are coupled to release a respective one of the clamping members. A deflection control mechanism according to any one of the preceding claims, characterized in that each pinch element is a cylindrical roller (117, 117', 118, 118'). A deflection control mechanism as claimed in any preceding claim characterized in that the at least one unlocking member engages the first cylindrical member to rotate the first cylindrical member. deflection control mechanism claim 6 , characterized in that the unlocking element engages the first cylindrical element with such play that the clamping element is released upon rotation of the hand wheel (22, 23) before the unlocking element rotates the first cylindrical element. deflection control mechanism claim 7 in combination with claim 4 , characterized in that two compression springs (121, 121') are provided to bias the clamping elements into the wedge sections (115, 115', 116, 116'), each compression spring (121, 121') between a clamping element of a first pair of clamping elements and a subsequent clamping element of a second pair of clamping elements. A deflection control mechanism according to any one of the preceding claims, characterized in that between the at least one unlocking element and each of the at least one pair of clamping elements there is a respective unlocking tab (119, 119', 120, 120') which contacts the unlocking element and the respective clamping element. deflection control mechanism claim 9 , characterized in that each unlocking tab (119, 119', 120, 120') has a spreading surface (129, 130) which cooperates with a corresponding spreading surface (131, 132) of the at least one unlocking element in order to release a respective clamping element when the release tab in an axial direction with respect to a respective unlocking element from a clamping position in the respective wedge section (115, 115', 116, 116'). deflection control mechanism claim 10 , characterized in that the at least one unlocking element protrudes in the axial direction into the gap (107) and that the unlocking tab (119, 119', 120, 120') and the second cylindrical element are movable in the axial direction. A deflection control mechanism as claimed in any one of the preceding claims, characterized in that the deflection control mechanism (29) comprises a further drive wheel rotatably supported in or on the support structure, a further hand wheel (23), a further first cylindrical element rotationally coupled to the further drive wheel, and a further second cylindrical member rotationally coupled to the support structure, the further first and second cylindrical members being arranged to form a further substantially annular gap, the further gap comprising at least one further pair of opposed wedge portions, at least one further pair Clamping elements are arranged in the gap, each of the further pair of clamping elements being biased to be clamped in a respective one of the further wedge sections, and at least one further unlocking element coupled to the further handwheel being provided to release a respective one of the to release another pair of clamping elements. A steerable flexible endoscope having an elongate flexible shaft (30) including a steerable portion (31) deflectable by movement of at least one elongate control element, further comprising a deflection control mechanism (29) according to any one of the preceding claims. A method of controlling a flexible endoscope (10) having an elongate flexible shaft (30) including a steerable portion (31) deflectable by movement of at least one elongate control element, the flexible endoscope (10) having a deflection control mechanism ( 29) after one of the Claims 1 - 12 comprises wherein the steerable portion (31) is deflected by turning the handwheel (22, 23), the steerable portion (31) is maintained at a deflection angle determined by clamping one of the at least one pair of clamping members in a respective wedge portion (115, 115 ', 116, 116') of the essentially annular gap has been reached, and the steerable section (31) is unlocked by turning the handwheel (22, 23) again.

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