Patent Application
20240374122
This application claims priority from and the benefit of European Patent Application No. EP 23172889.0, filed May 11, 2023; the disclosure of said application is incorporated by reference herein in its entirety.
The present disclosure relates to an endoscope comprising an elevator at a distal end thereof. More particularly, the disclosure relates to an elevator control assembly of the endoscope, movable between a lowered elevator position and a raised elevator position, to change a direction of a tool or instrument inserted through an insertion cord of the endoscope.
Endoscopes, including specialized instruments, such as bronchoscopes, arthroscopes, colonoscopes, laparoscopes, gastroscopes and duodenoscopes, are well known from the state of the art and are used for visual examination and diagnosis of hollow organs and body cavities, as well as to assist in surgery, e.g. for a targeted tissue sampling. A distal tip unit of an endoscope, which is usually connected to a handle via a bending section and an insertion tube, can be inserted into a hollow organ or body cavity to be investigated with the endoscope. Both reusable and disposable, i.e. single-use, endoscopes are known from the state of the art.
Some endoscopes, in particular duodenoscopes, comprise a distal tip unit having a shovel-like elevator element, a so-called Albarran lever, via which a direction of a tool or an instrument inserted into a patient's body cavity via a working channel of the endoscope can be changed. The elevator element can be raised and lowered in order to set an angle with respect to a longitudinal axis of the distal tip unit at which the tool or instrument exits the distal tip unit into the patient's body cavity. In a raised position of the elevator element, the tool or instrument may point in a direction essentially perpendicular to the longitudinal axis of the distal tip unit. It is known to control the elevator element via a manually operable element, like a control lever, provided at the endoscope handle. Elevator mechanics are usually provided via which the manually operable element is connected to a (pull) wire which extends through the insertion cord of the endoscope and which is connected to the elevator element in the distal tip unit.
In related art endoscopes, it is known to invert a motion of the manually operable element by the elevator mechanics such that a clockwise-movement of the manually operable element results in an upward-movement of the elevator element and that an anticlockwise-movement of the manually operable element results in a downward-movement of the elevator element. An operator of related art endoscopes is used to said described motion inversion.
In order to reach the motion inversion it is known from related art endoscopes to connect a slider rod to an operation wheel connected to the manually operable element at a portion of the operation wheel which is essentially/approximately diametrically opposed to a portion of the operation wheel where the manually operable element is connected to the operation wheel. Expressed differently, the slider rod is not connected to the operation wheel at a side of the same where the manually operable element is provided but is connected to the operation wheel at an opposed side. Therefore, the slider rod moves around inside a handle housing of the endoscope handle, in particular in a central portion of an accommodation space defined by the handle housing, or even in a portion of the handle housing which is close to a surface/wall which is opposed to a surface/wall at which the manually operable element is provided.
Due to the moving slider rod inside the handle housing, much installation/accommodation space provided inside the handle housing cannot be used for other parts/components like valves, which are intended to be accommodated inside the handle housing. Additionally, such a mechanism is disadvantageous since a pulling force applied via a slider rod is not uniform from start to finish of an operating range. This makes it complicated for a user to operate and can lead to miscalculations when operating the elevator element.
Further, solutions comprising a rack and pinion mechanism are known. However, these do not provide control mechanisms that are easy and cost-efficient in manufacturing, can be flexibly combined with various endoscopes providing different functions, and/or are difficult to handle.
In view of the above-described problems, it is an object of the present disclosure to provide an endoscope, which shall reduce or avoid the disadvantages of the prior art. In particular, it is an object of the disclosure to provide an endoscope having a control module configured for steering a distal tip unit of the endoscope by bending a bending section and for controlling an elevator mechanism, which endoscope is easily operable and assemblable, and which control module requires little assembly space. Preferably, the endoscope is configured for single-use, whereby it is discarded after use in a patient.
The control module comprises: a first steering control assembly including a first wire drum, a base mounted to an inside of the endoscope handle, and an elevator control assembly comprising a toothed rack connected or connectable to an elevator wire and an elevator drive gear, which forms a toothed portion configured to (directly or indirectly, preferably directly) engage the toothed rack, said elevator drive gear being rotatably connected to the base to be rotatable around the control axis at an axial side of the first wire drum, said axial side being axially opposite to the first steering control element, i.e. with respect to the axial direction, said elevator drive gear is provided on the one axial side of the first wire drum, and the first steering control element is provided on the other axial side of the first wire drum, so that the first wire drum is axially provided between the first steering control element and the elevator drive gear.
A manually operable first steering control element is configured to receive a steering input by a user and is rotatably connected to the base to be rotatable around a control axis. A first wire drum, which is non-rotatably connected to the first steering control element, is configured for driving a first steering wire.
The base, the first steering control assembly comprising the first steering controller and the first wire drum, and the elevator control assembly may be referred to as a control module for convenience. The control module may include a second steering control assembly.
Expressed in other words, a control module for an endoscope is provided, said control module serving as a manual input unit for the user to steer various elements of the endoscope such as a bending section of an insertion cord and an elevator lever of a distal tip unit of said endoscope. Driving elements of the control module such as an elevator drive gear for driving the elevator mechanism and a wire drum for driving a steering wire for bending of the bending section can be preassembled on a base, said base being configured for quick and easy assembly to an endoscope handle, e.g. via bolts, a snap-fit connection, a clamping connection between parts of the handle housing or handle shell, heat staking or the like. Manually operable control and braking elements adapted for user input to drive or lock/brake the bending mechanism can also be preassembled and can be connected to the driving elements and the endoscope quickly and simply, e.g. via a snap-fit connection. Accordingly, assembly of the control assembly to the endoscope is simple and cost effective.
Advantageously, a modularly installable control module is provided which can be assembled into different kinds of endoscopes, such as duodenoscopes, gastroscopes, colonoscopes, etc. That means that the same handle housing, which in the present case is used with an elevator, can also be used for endoscopes without an elevator. I.e. no design change of the handle housing is necessary for endoscopes with or without an elevator. Further, a control stack/control assembly and a handle housing can be produced in high numbers, which is cost-efficient. Additionally, it is possible to have lower numbers (in total and of different parts) on stock, such that a risk of misassembly is lowered.
Further, since the elevator is operated via a rack and pinion mechanism, a uniform and easily calculable transmission of force to the elevator element is achieved. Thus, user errors are reduced. Further, such a mechanism is very simple and very few parts are needed, thus saving cost for manufacture and assembly. Due to the small number of parts, only few interfaces between such parts need to be provided. Therefore, play in the elevator control assembly can be reduced and a direct and precise control of the elevator control assembly can be achieved. Further, the elevator drive gear is formed at a position, which is arranged axially offset from at least the first wire drum towards an inside of the endoscope handle. Accordingly, an inner radius or diameter of the elevator drive gear is not limited by an outer radius or diameter of said first wire drum. Thus, the elevator drive gear can be made particularly small and an advantageous transmission ratio can be achieved. Often (preferably) the transmission ratio is selected so that the necessary input movement of the control lever is not excessive, i.e. a small angular movement of the elevator control lever provides a large angular movement of the elevator. However sometimes (alternatively preferred) torque is taken into consideration for the transmission ratio. Preferably, an inner radius or diameter of the elevator drive gear is at most 10% larger than an outer radius or diameter of the first wire drum, preferable at most 5% larger, further preferably smaller than the outer radius or diameter of the first wire drum. Also, an axial position of said elevator drive gear can easily be adapted to accommodate functional elements of the endoscope, such that the above described arrangement does not result in a waste of construction space.
In general, in the context of this disclosure, for directions such as “circumferentially”, “axially” or “radially”, the control axis serves as a reference. Further, “axially outwards” refers to a direction towards an outer side of the endoscope handle in a direction parallel to the control axis and “axially inwards” refers to a direction towards an inside of the endoscope handle in a direction parallel to the control axis, i.e. in a direction opposite to “axially outwards”. “Manually operable” means that the steering element is at least partially arranged outside of the endoscope handle such that the user can reach it without disassembly of the endoscope handle. A steering control element is preferably a control knob or hand wheel. The toothed portion may extend along the entire circumference of the elevator drive gear. Preferably, the toothed portion only extends along a portion of the circumference, which will mesh with the toothed rack in a rotational operating range of the elevator drive gear. The base provides a static bearing, being fixedly connected to the endoscope handle and forming various bearing surfaces for movably supporting elements of the control module. The wire drum is configured to wind up or loosen a steering wire in order to pull in or to loosen said steering wire.
Preferably, the control module may have a second steering control assembly comprising a manually operable second steering control element, which is provided for receiving a steering input by a user and is rotatably connected to the base to be rotatable around the control axis (i.e. coaxial with the first steering control assembly), and a second wire drum, which is non-rotatably connected to the second steering control element and is configured for driving a second steering wire.
Expressed in other words, the endoscope—as an alternative to a two-way bending endoscope—may be provided as a four-way bending endoscope, which allows bending of the endoscope in four directions via the (first) steering control element and the second steering control element. Further, the first and second steering control elements can optionally be blocked or brake applied independently from each other by a dedicated braking mechanism described in more detail below. A functional structure of the second steering control assembly can be essentially the same as that of the first steering control assembly. Preferably, the second steering control assembly is inserted or nested inside the first steering control assembly. I.e. the first steering control element and the first wire drum may be arranged axially between the second steering control element and the second wire drum, said first elements being connected by a hollow shaft extending through the first steering control assembly. This achieves a particularly space-efficient structure, which is easily preassembled, thus saving costs.
Preferably, as mentioned above, the control module may further comprise a first braking mechanism adapted to brake the first steering mechanism and/or a second braking mechanism adapted to brake the second steering mechanism. The first and second braking mechanisms may comprise a friction fit assembly accommodated in the corresponding steering control element and operable via a braking control element supported adjacent to the respective steering control elements.
Preferably, the base forms a casing accommodating at least the first wire drum. The casing may comprise at least a first dome portion or a first capsule portion forming a receptacle for the first wire drum. Optionally, the casing may accommodate the second wire drum. The casing may comprise a second dome portion or a second capsule portion accommodating the second wire drum and being separated by a wall portion from the first dome/capsule portion. In this manner, each steering control mechanism can be supported securely and precisely, thus allowing a precise and robust steering operation. The casing, optionally the first dome/capsule portion and/or the second dome/capsule portion, may be pot-shaped, with a bottom wall of said pot shape facing axially inwards. An open end of such a pot-shaped first dome/capsule may lie against an inner surface of the handle housing of the endoscope handle and be attached thereto. An open end of such a pot-shaped second dome/capsule may lie against an end portion of the first dome/capsule portion and be attached thereto.
Further preferably, a gear bearing surface for supporting the elevator drive gear in a radial and/or axial direction is formed at a side of the casing, said side being located axially inwards with respect to the endoscope handle along the control axis. This is a particularly simple way of providing a rotational bearing for the elevator drive gear, reducing material and assembly costs for a separate bearing. In other words, the gear bearing surface may have an axially facing gear bearing portion and/or a radially facing gear bearing portion. The axially facing gear bearing portion may be formed at an axial end surface of the base. Alternatively, two axially facing portions opposing each other may be formed between two portions of the base, particularly a first dome/capsule portion accommodating the first wire drum and a second dome/capsule portion accommodating the second wire drum. The radially facing gear bearing portion may be formed at a circumferential surface of a step or ring-shaped protrusion of the base. In other words, the gear bearing surface may be formed at a side of the base, which is axially opposite to the first wire drum and/or the second wire drum. That is, the first wire drum and/or the second wire drum may be separated from the gear bearing surface by a wall portion of the base.
Accordingly, it is particularly preferred that the elevator drive gear is rotatably connected to the base at a position axially inwards of both the first wire drum and the second wire drum. In particular, the elevator drive gear may be attached to an axially innermost end portion of the base. In this manner, a distance between the inner surface of the endoscope housing where the control unit is attached and the elevator drive gear may be maximized. Thus, space for various functional elements of the endoscope is provided between said inner surface and the elevator drive gear.
Alternatively preferred, the elevator drive gear can be rotatably connected to the base at a position axially between the first wire drum and the second wire drum. In this case, the elevator drive gear can be received and supported in a ring-shaped bearing slot formed between the first dome/capsule portion and the second dome/capsule portion. No additional securing means for securing the elevator drive gear at the base need to be provided. Thus, costs for securing means and assembly thereof are reduced. An especially precise guidance of the elevator drive gear in said bearing slot can be provided in a simple manner.
The user experience related to operation of the elevator drive may be negatively influenced by friction, and the friction coefficient should preferably be below 0.3, such as in the interval 0.1-0.3. Especially for single use endoscopes it is preferred to use plastic materials, such as thermoplastic materials, and producing the parts by e.g. injection moulding. Friction between components of the same thermoplastic can be considerably higher than for dissimilar materials. Preferably, the gear bearing surface of the base, preferably an entire member forming said gear bearing surface, is made of a material containing a (proprietary) lubricant. A (proprietary) lubricant is a lubricating material such as Teflon particles or a silicon material integrated into a base material to reduce friction between two members that move relative to each other. For example, a material containing a (proprietary) lubricant may be a compound based on a Polycarbonate such as a LNP™ LUBRILOY™ compound.
Preferably, the base forms a rack bearing surface for slidably supporting the toothed rack to slide in a plane transverse to the control axis, in an extending direction (i.e. longitudinal direction) of the toothed rack. Said rack bearing surface is preferably formed at a position adjacent or near to the above described gear bearing surface. The rack bearing surface may comprise an axially facing rack bearing portion supporting the toothed rack in the axial direction, e.g. at an inner end surface of the first or second dome/capsule portion. Further, the rack bearing surface may comprise a lateral rack bearing portion supporting the toothed rack laterally along an extension direction of the toothed rack, i.e. in a plane parallel to the control axis. Preferably, the lateral rack bearing portion supports the toothed rack at a side opposite to teeth of the toothed rack. Alternatively or additionally, the lateral rack bearing portion may support the toothed rack at a side of the teeth of the toothed rack, at a flat portion adjacent to the teeth. Alternatively or additionally, the lateral rack bearing portion may support the toothed rack via a rail and groove, one of which is formed in the toothed rack and one of which is formed by the base. The axial rack bearing portion is preferably flush with or formed on the same surface as the gear bearing surface.
Preferably, the elevator drive gear is fixedly connected to, preferably integrally formed with, an elevator control lever. Said elevator control lever extends radially outwards. In particular, said elevator control lever is dimensioned to extend through a slot in the handle housing, such that a grip end of the elevator control lever is manually operable. In particular, the elevator control lever may extend directly radially outwards starting from the elevator drive gear. I.e. the elevator control lever may extend (exclusively) in a plane comprising the elevator drive gear. In this case, the elevator control lever and the elevator drive gear are particularly simple elements which do not need much construction space.
Alternatively, it may be advantageous if the elevator control lever is connected to the elevator drive gear via an axially extending intermediate portion. In this case, the control element can be adapted to a standard endoscope handle where the slot is at a predefined position. Thus, an axial position of the elevator drive wheel can be optimized. The axially extending intermediate portion may be a ring-shaped or cone-shaped portion protruding from the elevator drive gear. Alternatively or additionally, the axially extending intermediate portion may comprise a rod portion connecting the elevator drive gear and the elevator control lever, in particular a rod portion extending diagonally with respect to the control axis.
According to the above-described arrangement, the elevator control lever can be long compared to a radius of the elevator drive gear, thus achieving an advantageous transmission ratio of an operating force, which is applied to the elevator control lever. Preferably, a ratio defined by a distance between a grip end of the elevator control lever and the control axis with respect to the working radius or the elevator drive gear being at least 2, preferably at least 2.3, further preferably at least 2.6.
On the other hand, a toothed rack can be provided with a variable toothing, preferably a variable distance between teeth. In this case, a specific transmission ratio adapted to specific operations can be provided via a simple structure.
Preferably, the control module comprises a module bearing surface formed at a position axially between the first steering control element and the first wire drum, in case of the second steering mechanism also between the second steering control element and the second wire drum. In particular, the module bearing surface may be formed at a radially outer surface of the first steering control assembly, further preferably at the first hollow shaft connecting the first steering control element and the first wire drum. In particular, the module bearing surface is configured to support a housing bearing surface of the endoscope handle. That is, the module bearing surface and the housing bearing surface form a sliding bearing. In other words, the first and/or second steering control mechanisms are rotatably supported at the endoscope housing via the module bearing surface. In particular, the control module is configured to be supported at the handle housing such that a wall portion of the housing is arranged axially between the first and/or second wire drums and the elevator drive gear on an inner (one) side and the steering control elements on the outer (other) side. Accordingly, interfaces between the control module and mechanisms of the endoscope are protected in the handle housing while manual control elements are easily reachable for a user.
Preferably, the toothed rack may form a wire connecting portion, particularly a ring-shaped portion adapted to hold a loop formed at a proximal end of the elevator wire. This allows a simple connection between the toothed rack and the elevator wire. Further, the ring-shaped portion may be selectively provided at a distal or a proximal end of the toothed rack. Accordingly, an arrangement of the toothed rack can be adapted to the available space inside the endoscope handle. Optionally, the same toothed rack can be meshed with the elevator drive wheel in either orientation.
Connection elements of the control module and of the endoscope for mounting the control module to the endoscope handle may be standardized, such that various control modules and various endoscopes may be combined. Thus, a constructional platform system can be provided, which allows high flexibility with providing different combinations of control modules with the same endoscope handle or vice versa, while saving costs.
Additionally or alternatively, the object underlying the present disclosure is achieved by an endoscope comprising: a proximal endoscope handle equipped with an above-described control module with at least the first wire drum and the elevator drive gear being accommodated inside the endoscope handle; an insertion cord extending from the endoscope handle and configured to be inserted into a patient's body cavity, the insertion cord comprising an insertion tube, a bending section and a distal tip unit; an elevator mechanism comprising an elevator element, which is accommodated in the distal tip unit and movable between a first lowered elevator position and a second raised elevator position for changing a direction of a tool or an instrument inserted through the insertion cord, and an elevator wire, which is connected to the elevator element to drive said elevator element, extends through the insertion cord and is connected to the toothed rack to be operated via the elevator drive gear; and a first steering wire connected to the bending section, extending through the insertion cord and being operably connected to the first wire drum, said first steering wire being operable to steer the distal tip unit by bending the bending section.
The endoscope may have features discussed above with respect to the control module and its arrangements and interfaces with a corresponding endoscope.
In particular, the endoscope is a single-use endoscope. In such single use endoscopes, costs for manufacture and assembly are minimized. For this, extended use of plastic materials is applied in order to achieve a low cost product based on inexpensive materials. In addition, a structure of such endoscopes is optimize to achieve a low carbon footprint.
Preferably, an axial space is formed between the elevator drive gear and an inner surface of the endoscope handle where the control module is mounted. Further preferably, at least one functional element, in particular at least one valve mounted to the endoscope housing, is at least partially received in said axial space. Expressed in other words, the endoscope handle may comprise at least one valve or other functional element arranged at a position radially adjacent to the control module and axially located between the elevator drive gear and a housing portion of the endoscope handle where the control module is mounted. Thus, it is possible to optimize use of construction space inside the endoscope handle.
Preferably, according to one modification, the toothed rack is positioned at a first radial side of the control module, said first radial side facing the at least one functional element. This is particularly advantageous, since in this case, only two parts (the toothed rack and the elevator drive gear) are necessary in order to drive the elevator element in a specific direction when the elevator control lever is operated in a first predetermined direction. Thus, the corresponding mechanism is particularly simple, cost effective and with minimized play. In particular, the elevator wire may be connected to the elevator drive wheel only through the toothed rack for transmission of force.
Alternatively, the toothed rack may be positioned at another radial side of the control module, said second radial side being opposite to the at least one functional element. In this case, an intermediate gear is preferably provided, which meshes with the elevator drive gear on one side and the toothed rack on another other side. In this manner, the direction in which the elevator element is operated when the elevator control lever is operated in the first predetermined direction can be maintained. This is particularly advantageous if no constructional space is available between the elevator drive gear and the functional element.
Additionally or alternatively, the problem underlying the present disclosure is solved by a system including the above-described endoscope and a monitor connectable to said endoscope.
The above-mentioned embodiments and variations, features and advantages thereof will be further elucidated by the following illustrative and nonlimiting detailed description of embodiments disclosed herein with reference to the appended drawings, wherein:
The bending movement in one of the bending planes (in a first and second direction) is controlled via a first steering control assembly including a manually operable first steering control element 7a, in particular formed as a first hand wheel. A first braking mechanism is preferably provided, which has a manually operable first braking control element 8a, in particular formed as a rotatable lever, and is adapted to brake the first steering control assembly, when said first braking control element 8a is operated by a user.
Further, the bending movement in the other one of the bending planes (in a third and fourth direction) is controlled by a second steering control assembly including a manually operable second steering control element 7b, in particular formed as a second hand wheel. A second braking mechanism is preferably provided, which has a manually operable second braking control element 8b, in particular formed as a rotatable knob, and is adapted to brake the second steering control assembly, when said second braking control element 8b is activated by the user. The second steering control assembly and the second braking mechanism may be omitted and the bending section may only be bendable in two directions.
As shown in
Next, the control module 6 according to a first embodiment of the present disclosure mounted to the endoscope handle 2, is described with reference to
The control module 6 comprises a base 15, which is exchangeably mounted on the endoscope handle 2, in particular to an inside of the endoscope handle 2. The base 15 may have one single base part or two separate base parts, i.e. a first base part (member) 15a and/or a second base part (member) 15b. The base 15 comprises or is fixedly connected to a central shaft 16 and a sleeve-like intermediate support portion, or intermediate support sleeve, 17 coaxially surrounding the central shaft 16. In the present example, the second base member 15b integrally forms the central shaft 16. Further in the present example, the first base member 15a integrally forms the intermediate support portion 17. The central shaft 16 defines the control axis 14. The intermediate support portion 17 and the central shaft 16 extend through an opening, or central shaft hole 2″ (shown in
The intermediate support portion 17 supports the first steering control assembly and the first braking mechanism. The central shaft 16 supports the second steering control assembly and the second braking mechanism.
At the outer side of the endoscope handle 2, the first braking control element 8a, the first steering control element 7a, the second steering control element 7b and the second braking control element 8b are arranged in this order starting from an outer side of the endoscope handle 2. In this arrangement, the first braking control element 8a is arranged adjacent to the endoscope handle 2 (an outer surface of the handle housing) and the second braking control element 8b is furthest from the endoscope handle 2 (an outer surface of the handle housing).
The intermediate support portion 17 rotatably supports a first hollow shaft 18a of the first steering control assembly, which is integrally formed with a first wire drum 19a received within the endoscope handle 2. In particular, the first wire drum 19a is received in a first dome portion 151a formed by the base 15, in particular, by the first base member 15a. First steering wires 20a are wound around the first wire drum 19a and extend through the insertion cord to the bending section 4 in order to drive the bending of the bending section 4 in one of the bending planes. Outside of the endoscope handle 2, the first steering control element 7a is non-rotatably connected to the first hollow shaft 18a. Thus, by rotating the first steering control element 7a, the first hollow shaft 18a and the first wire drum 19a are rotated around the control axis 14, pulling or loosening the first steering wire 20a to control the bending section 4.
The central shaft 16 rotatably supports a second hollow shaft 18b, which is integrally formed with a second wire drum 19b received within the endoscope handle 2. In particular, the second wire drum 19b is received in a second dome portion, or casing, 151b formed by the base 15, in particular by the second base part/member 15b. Said second dome portion, or casing, 151b is arranged inwards of the first dome portion 151a, i.e. on a side thereof facing inwards with respect to the handle housing. Second steering wires 20b are wound around the second wire drum 19b and extend through the insertion cord to the bending section 4 in order to drive the bending of the bending section 4 in the other one of the bending planes. The second steering control element 7b, which is arranged outside the endoscope handle 2, is non-rotatably connected to the second hollow shaft 18b. Thus, by rotating the second steering control element 7b, the second wire drum 19b is rotated around the control axis 14, pulling or loosening the second steering wires 20b to control the bending section 4.
At a radially outer surface of the control module, at a position axially between the first and second wire drums 19a, 19b on one side and the first and second steering control elements 7a, 7b on the other side, a module bearing surface 21a is formed as a supporting interface with the handle housing. Preferably, said module bearing surface 21a is formed at a radially outer surface of the first hollow shaft 18a. In particular, the handle housing forms a radially inner housing bearing surface 21b formed at the opening in the handle housing, through which the control module 6 is inserted. The module bearing surface 21a and the radially inner housing bearing surface 21b of the handle housing may be processed (e.g. polished) to form sliding bearing surfaces.
The following description refers to “the braking mechanism” and details first features of the first braking mechanism and second features of the second braking mechanism, which are similar to each other. Similar to the first and second steering control assemblies detailed above, similar features of the first and second braking mechanisms are denoted with reference signs including the letter “a” corresponding to first elements of the first braking mechanism and with reference signs including the letter “b” corresponding to second elements of the second braking mechanism.
The (selectively first or second) braking mechanisms are described in detail below with reference to
Each braking portion 22a, 22b includes an axially movable (selectively first or second) carrier 24a, 24b, which on one axial side forms a trough for accommodating the spring element 23a, 23b and supporting it in the axial direction. Axially opposite to the spring element 23a, 23b the carrier 24a, 24b forms a flat supporting surface, where a (selectively first or second) stack of friction discs 25a, 25b is supported. This stack of friction discs 25a, 25b is a friction element according to the disclosure.
In the stack of friction discs 25a, 25b, a number of steering side friction discs and a number of brake side friction discs are alternatingly stacked. The steering side friction discs are non-rotatably and axially slidably engaged with the steering control element 7a, 7b. The brake-side friction discs are non-rotatably and axially slidably connected to the handle housing, e.g. via the central shaft 16 or directly at a portion of the handle housing.
Opposite to the carrier 24a, 24b, a (selectively first or second) plunger 26a, 26b is provided to compress the stack of friction discs 25a, 25b between the carrier 24a, 24b and the flat contact surface, creating a friction fit in the stack of friction discs 25a, 25b and locking the steering control element 7a, 7b with respect to the handle housing. The plunger 26a, 26b is operated via the braking control element 8a, 8b, e.g. via a cam formed on said braking control element 8a, 8b.
Further, the control module 6 comprises an elevator drive gear 27 and a toothed rack 28. Teeth of the toothed rack 28 engage with teeth of the elevator drive gear 27. The toothed rack 28 is connected or connectable to the elevator wire 12 as shown in
The base 15, in particular the second base member 15b, forms a gear bearing surface 30 for supporting the elevator drive gear 27. The gear bearing surface 30 is formed at a position axially inwards with respect to the handle housing, i.e. away from the outer side of the handle housing along an axial direction of the control axis 14. The gear bearing surface 30 may have an axial gear bearing portion. In particular, the axial gear bearing portion is formed at a surface of the base 15, in particular the second base member 15b, facing axially inwards with respect to the handle housing. Preferably, the base 15, in particular the second base member 15b, further forms a rack bearing surface 31 for slidably supporting the toothed rack 28. Preferably, said rack bearing surface 31 is adjacent to, in particular flush with, the axial gear bearing portion. In particular, the rack bearing surface 31 is formed on the same surface as the axial gear bearing portion of the gear bearing surface 30.
According to the first embodiment shown in
According to the second embodiment shown in
According to one modification of the first or second embodiment, said modification being exemplarily shown in
The elevator drive gear 27 may have a toothed portion only at a side facing the toothed rack 28. The elevator control lever 29 is preferably connected to the elevator drive gear 27 at a side diametrically opposite to the toothed portion of the elevator drive gear 27.
The toothed rack 28 forms at its one end a wire connecting portion 34, which may be ring-shaped, with the elevator wire 12 being wound in a loop around said ring-shaped wire connecting portion 34. Modifications of this wire connecting portion are schematically shown in
In the exemplary embodiments shown above, the toothed rack 28 is arranged at a side of the elevator drive gear 27 which faces the at least one valve 33 and meshes directly with the elevator drive gear 27. Alternatively, as schematically shown in
The following items are variations and examples of the embodiments described with reference to the figures.
| Number | Date | Country | Kind |
|---|---|---|---|
| 23172889.0 | May 2023 | EP | regional |
