ENDOSCOPE HAVING AN ADJUSTABLE BRAKING MECHANISM

Abstract

An endoscope including steering and braking mechanisms. The braking mechanism includes a manually operable braking control element, a friction element which is axially translatable along a control axis to engage or disengage with the steering mechanism, and a cam pairing transmitting force between the braking control element and the friction element and transforming the braking input into an axial translation of the friction element. The cam pairing has a cam surface and a cam axially contacting the cam surface. The cam surface forms a first ramp section for translating the friction element from a first braking position to an intermediate braking position, a second ramp section for translating it from the intermediate braking position to a second braking position, and an intermediate section forming a tactile structure arranged between the first ramp section and the second ramp section and defining the intermediate braking position.

Claims

1. An endoscope comprising: a handle; an insertion cord extending from the handle and comprising an insertion tube, a bending section and a distal tip unit; a steering mechanism comprising a steering control and a steering wire, the steering control being rotatable around a control axis, and the steering wire connecting the steering control with the bending section to bend the bending section when a user manually rotates the steering control; and a braking mechanism configured to brake the steering mechanism, the braking mechanism comprising: a braking control operable to receive a braking input by the user; a friction element which is axially translatable in an axial direction defined by the control axis to engage or disengage with the steering mechanism; and a cam pairing having a cam surface unit forming a cam surface and a cam contacting the cam surface in the axial direction, the cam being connected to or integrally formed with the braking control or the friction element, the cam surface unit being connected to or integrally formed with the other of the braking control element or the friction element, wherein the cam surface comprises a first ramp section, a second ramp section, and an intermediate section arranged between the first ramp section and the second ramp section and forming a tactile structure defining an intermediate braking position, wherein rotation of the braking control causes the cam to slide along the cam surface to transform the braking input into an axial translation of the friction element, and wherein the first ramp section translates the friction element from a first braking position to the intermediate braking position, and the second ramp section translates the friction element from the intermediate braking position to a second braking position.

2. The endoscope of claim 1, wherein the braking control is rotatable around the control axis, the cam surface extends in a circumferential direction and the first ramp section and the second ramp section extend in the circumferential direction and in the axial direction.

3. The endoscope of claim 2, wherein at least two, preferably three, cam surfaces are provided, which are dimensioned and arranged to form a circle around the control axis.

4. The endoscope of claim 1, wherein the tactile structure forms a recess between the first ramp section and the second ramp section.

5. The endoscope of claim 4, wherein the intermediate section forms a first shoulder or step adjacent to the first ramp section, a second shoulder or step adjacent to the second ramp section, and an intermediate flat surface arranged between the first shoulder or step and the second shoulder or step.

6. The endoscope of claim 5, wherein the first shoulder or step preferably has a steeper inclination than the second shoulder or step.

7. The endoscope of claim 1, wherein the tactile structure forms a projection between the first ramp section and the second ramp section.

8. The endoscope of claim 1, wherein the cam surface further comprises a first flat surface at a position corresponding to the first braking position and/or a second flat surface at a position corresponding to the second braking position.

9. The endoscope of claim 8, wherein the first ramp section comprises a first inclination angle, the second ramp section comprises a second inclination angle, and the first inclination angle and the second inclination angle differ by at most +/−5 degrees.

10. The endoscope of claim 9, wherein a reference line extending along and from the first ramp section is tangential to the second ramp section at a location where the second ramp section connects with the intermediate section.

11. The endoscope of claim 1, wherein the first ramp section comprises a first inclination angle, the second ramp section comprises a second inclination angle, and the second inclination angle is less than the first inclination angle.

12. The endoscope of claim 1, wherein the cam is non-rotatably connected to the braking control or formed integrally with the braking control.

13. The endoscope of claim 12, wherein the cam is non-rotatably connected to the braking control or formed integrally with the braking control on an inner axial or circumferential surface thereof.

14. The endoscope of claim 1, wherein the cam has a contact edge which tapers in a direction towards the cam surface unit.

15. The endoscope of claim 1, wherein a pressurizing element is provided which supports a spring element on one axial side and the frictional element on another axial side, and wherein the pressurizing element forms a stop surface acting in a direction opposite to the spring element and adapted to contact a rim portion of the steering control element.

16. The endoscope of claim 1, wherein the braking control and the cam surface unit engage with each other via a circumferential stopping structure including a circumferentially extending stopper groove providing two circumferential stopper surfaces and an axially extending stopper pin which are slidable with respect to each other in the axial direction and in the circumferential direction.

17. The endoscope of claim 18, further comprising: a second steering mechanism comprising a second steering control rotatable around the control axis, and a second steering wire connecting the bending section with the second steering control to bend the bending section in the second direction when the user manually rotates the second steering control; a second braking mechanism configured to brake the second steering mechanism and comprising: a second braking control operable to receive a second braking input by the user and being rotatable around the control axis; a second friction element which is axially translatable in the axial direction to engage or disengage with the second steering mechanism; and a second cam pairing having a second cam surface unit forming a ramp section and a second cam contacting the ramp surface of the second cam surface unit in the axial direction to transform the second braking input into an axial translation of the second friction element, the second cam being connected to the second braking control or the second friction element, the second cam surface unit being connected to the other of the second braking control or the second friction element; and a click interface formed by the second braking control and a portion of the handle, the click interface including a click recess or click protrusion as a clicking structure, which is formed at the second braking control or the portion of the endoscope handle, and a spring arm, which is formed at the other of the second braking control or the portion of the endoscope handle, wherein the spring arm is configured to engage with the clicking structure to define an intermediate braking position of the second braking mechanism and to resiliently bend away from the clicking structure, and wherein the ramp section translates the friction element from a first braking position to the intermediate braking position of the second braking mechanism and from the intermediate braking position to a second braking position.

18. The endoscope of claim 17, wherein the second braking control has a plate-like base portion, which forms the second cam surface or the second cam facing towards one side and which forms the spring arm facing towards an opposing side.

19. The endoscope of claim 18, wherein the spring arm is formed from the base portion of the second braking control in the manner of a bridge formed between two longitudinal slits.

20. An endoscope comprising: a handle; an insertion cord extending from the handle and comprising an insertion tube, a bending section and a distal tip unit; a steering mechanism comprising a steering control and a steering wire, the steering control being rotatable around a control axis, and the steering wire connecting the steering control with the bending section to bend the bending section when a user manually rotates the steering control; and a braking mechanism configured to brake the steering mechanism, the braking mechanism comprising: a braking control operable to receive a braking input by the user; a friction element which is axially translatable in an axial direction defined by the control axis to engage or disengage with the steering mechanism; a cam pairing having a cam surface unit forming a ramp section and a cam contacting the ramp surface of the cam surface unit in the axial direction to transform the braking input into an axial translation of the friction element, the cam being connected to the braking control or the friction element, the cam surface unit being connected to the other of the braking control or the friction element; and a click interface formed by the braking control and a portion of the handle, the click interface including a click recess or click protrusion as a clicking structure, which is formed at the braking control or the portion of the endoscope handle, and a spring arm, which is formed at the other of the braking control or the portion of the endoscope handle, wherein the spring arm is configured to engage with the clicking structure to define an intermediate braking position and to resiliently bend away from the clicking structure, and wherein the ramp section translates the friction element from a first braking position to the intermediate braking position and from the intermediate braking position to a second braking position.

21. A visualization system comprising an endoscope according to claim 1 or an endoscope according to claim 20, and a monitor (M) connectable to the endoscope.

Description

BRIEF DESCRIPTION OF FIGURES

[0037] The following figures illustrate an exemplary embodiment of the disclosure. The disclosure is not limited to the embodiment described below. Other embodiments, combinations of embodiments and modifications may be provided within the scope of protection defined by the claims.

[0038] FIG. 1 shows a system including a monitor and an endoscope according to a preferred embodiment of the disclosure.

[0039] FIG. 2 shows a cross-section of first and second steering and braking mechanisms of the endoscope according to FIG. 1.

[0040] FIG. 3 shows a sectional view of the first braking mechanism according to FIGS. 1 and 2 in a non-braking state and FIG. 4 shows a braking state thereof.

[0041] FIG. 5 shows a sectional view of the second braking mechanism according to FIGS. 1 and 2 in a non-braking state and FIG. 6 shows a braking state thereof.

[0042] FIG. 7 shows a preassembled unit of the first braking mechanism of the endoscope according to FIGS. 1 and 2.

[0043] FIG. 8 shows the first braking mechanism according to FIG. 2 in a partial sectional side view.

[0044] FIG. 9 shows a schematic illustration of a working principle of the second braking mechanism according to FIGS. 1 and 2.

[0045] FIG. 10 shows the second braking mechanism according to FIGS. 1 and 2 in a side view.

[0046] FIG. 11 shows an endoscope handle of the endoscope according to FIG. 1 in a disassembled state.

[0047] FIG. 12 shows a second breaking control element in a disassembled state.

DETAILED DESCRIPTION

[0048] FIG. 1 shows a schematic view of an endoscope 1, which is preferably a single-use endoscope. The endoscope 1 has a proximal endoscope handle 2 and an insertion cord extending distally from the endoscope handle 2. The insertion cord has an insertion tube 3 connected to the endoscope handle 2. The insertion cord 3 further includes a bending section 4 connected to a distal end of the insertion tube 3 and a distal tip unit 5 connected to a distal end of the bending section 4. The bending section 4 is configured to perform a bending/pivoting/swiveling movement in four different, preferably orthogonal, directions, i.e. two bending planes. This enables a steering of the endoscope 1. Mounted to the endoscope handle 2, control elements 6a, 6b, 7a, 7b for controlling the bending section 4 are provided, which are described in detail below. Further, FIG. 1 shows a monitor M, which is connected or connectable to the endoscope 1, the monitor M and the endoscope 1 forming a system.

[0049] The bending/pivoting/swiveling movement in one of the bending planes (in a first and second direction) is controlled by a first steering mechanism including a manually operable first steering control element, or first steering control, 6a, in particular formed as a first steering wheel. A first braking mechanism is provided, which has a manually operable first braking control element 7a, in particular formed as a knob, and is adapted to brake the first steering mechanism, when said first braking control element, or first braking control, 7a is activated by a user.

[0050] Further, the bending/pivoting/swiveling movement in the other one of the bending planes (in a third and fourth direction) is controlled by a second steering mechanism including a manually operable second steering control element, or second steering control, 6b, in particular formed as a second steering wheel. A second braking mechanism is provided, which has a manually operable second braking control element, or second braking control, 7b, in particular formed as a rotatable lever, and is adapted to brake the second steering mechanism, when said second braking control element 7b is activated by the user.

[0051] Controls, whether steering or braking, can be a wheel, a knob, a lever, a portion of a wheel, and other structures comprising an opening around a central shaft 8 connected to and extending from the handle, rotation of the control around the shaft executing the intended function of steering or braking. Because the controls can be concentric, their position in a stack of elements can limit which external shape the control takes.

[0052] The first braking control element 7a, the first steering control element 6a, the second steering control element 6b and the second braking control element 7b are rotatably supported by a central shaft 8 shown e.g. in FIG. 2 and are arranged in this order. In this arrangement, the second braking control element 7b is adjacent to the endoscope handle 2 (a housing of the endoscope handle 2) and the first braking control element 7a is furthest from the (housing of the) endoscope handle 2. The central shaft 8 is fixedly connected to the endoscope handle 2 and defines a control axis 9. In particular, FIG. 2 shows a cross-section of the first braking mechanism and the first steering mechanism (the first control mechanism) as well as the second steering mechanism and the second braking mechanism (the second control mechanism) of the endoscope 1 according to FIG. 1.

[0053] The central shaft 8 rotatably supports a hollow shaft 10 of the first steering mechanism, which is integrally formed with a first wire drum 11a received within the endoscope handle 2. First steering wires 12a are wound around the first wire drum 11 a and extend through the insertion cord to the bending section 4 in order to drive the bending/pivoting/swiveling of the bending section 4 in one of the bending planes. Outside of the endoscope handle 2, the first steering control element 6a is non-rotatably connected to the hollow shaft 10. Thus, by rotating the first steering control element 6a, the hollow shaft 10 and the first wire drum 11 a are rotated around the control axis 9, pulling or loosening the first steering wires 12a to control the bending section 4.

[0054] Surrounding the hollow shaft 10, an intermediate support portion 13 is provided, which is fixedly connected to the endoscope handle 2 and rotatably supports the second steering control element 6b, which is arranged outside the endoscope handle 2 and is non-rotatably connected to a second wire drum 11b arranged inside the endoscope handle 2. Second steering wires 12b are wound around the second wire drum 11b and extend through the insertion cord to the bending section 4 in order to drive the bending/pivoting/swiveling of the bending section 4 in the other one of the bending planes. The second wire drum 11b is fixedly connected to the second steering control element 6b. Thus, by rotating the second steering control element 6b, the second wire drum 11 b is rotated around the control axis 9, pulling or loosening the second steering wires 12b to control the bending section 4.

[0055] 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. Such similar features are denoted both with reference signs including the letter “a” corresponding to the first braking mechanism and with reference signs including the letter “b” corresponding to the second braking mechanism.

[0056] The (selectively first or second) braking mechanism is described in detail below with reference to FIGS. 2 to 6. In particular, as can be seen in FIG. 2, the braking mechanism includes the (selectively first or second) braking control element 7a, 7b, a (selectively first or second) friction fit assembly 14a, 14b and a (selectively first or second) spring 15a, 15b. The friction fit assembly 14a, 14b and the spring 15a, 15b are accommodated in the (selectively first or second) steering control element 6a, 6b. The spring 15a, 15b is axially supported on the steering control element 6a, 6b and preloads the friction fit assembly 14a, 14b towards the braking control element 7a, 7b.

[0057] The friction fit assembly 14a, 14b includes a (selectively first or second) pressurizing element 16a, 16b, which on one axial side forms a trough for accommodating the spring 15a, 15b and supporting it in the axial direction. Axially opposite and in particular radially outwards with respect to its trough, the pressurizing element 16a, 16b forms a flat supporting surface, where a (selectively first or second) stack of friction discs 17a, 17b is supported. This stack of friction discs 17a, 17b is a friction element according to the disclosure and is described in detail below.

[0058] Further, the pressurizing element 16a, 16b forms a stop and engagement structure in the form of (selectively first or second) clip-in arms 18a, 18b which are adapted to resiliently snap into an engagement structure formed by the steering control element 6a, 6b. The clip-in arms 18a, 18b are adapted to contact a rim of the steering control element 6a, 6b in an axial direction to prevent the spring 15a, 15b from pushing the pressurizing element 16a, 16b out of the steering control element 6a, 6b. Further, the clip-in arms 18a, 18b engage with the pockets or openings formed in the steering control element 6a, 6b in such a manner, that a relative rotation thereof is prevented and an axial displacement thereof is possible.

[0059] In case of the first braking mechanism, as shown in FIGS. 3, 4 and 7, the corresponding (first) clip-in arms 18a are formed on an outer circumference of the corresponding (first) pressurizing element 16a. The (first) clip-in arms 18a of the first braking mechanism extend axially towards the first braking control element 7a and radially outwards. Their free ends are pushed axially against the rim of a pocket-shaped engagement structure formed by the first steering control element 6a. In case of the second braking mechanism, as shown in FIGS. 5 and 6, the corresponding (second) clip-in arms 18b are formed on an inner circumference of the corresponding (second) pressurizing element 16b. The (second) clip-in arms 18b of the second braking mechanism extend axially away from the second braking control element 7b and radially inwards in a hook-like manner. Their hook ends are pushed axially against the rim of an opening-shaped engagement structure formed by the second steering control element 6b.

[0060] In the stack of friction discs 17a, 17b, a number of steering side friction discs and a number of brake side friction discs are alternatingly stacked. The steering side friction discs form lugs extending radially outwards. In case of the first braking mechanism, this is best seen in FIG. 7. In case of the second braking mechanism, this is best seen in FIGS. 5 and 6. The lugs engage with a corresponding structure of the steering control element 6a, 6b to provide a non-rotatable and axially slidable connection between the steering-side friction discs and the steering control element 6a, 6b. The brake-side friction discs form lugs extending radially inwards to form a similar connection with a (selectively first or second) cam surface unit 19a, 19b of the friction fit assembly 14a, 14b. It is not excluded that instead of a stack of discs one disc can be used. The stack may comprise two discs. More discs increase the friction surfaces. However a properly structured disc (e.g. to prevent flexure) can apply or receive more pressure and thus be adequate for its function.

[0061] The (selectively first or second) cam surface unit 19a, 19b is arranged opposite to the pressurizing element 16a, 16b. The cam surface unit 19a, 19b has flat contact surfaces adapted to contact the stack of friction discs 17a, 17b. Thus, the stack of friction discs 17a, 17b is sandwiched between the pressurizing element 16a, 16b and the cam surface unit 19a, 19b. Further, the cam surface unit 19a, 19b extends axially inside the stack of friction discs 17a, 17b and engages with the brake side friction discs to form an axially slidable and non-rotatable connection.

[0062] The cam surface unit 19a, 19b is supported in an axially slidable and non-rotatable manner by a part fixed to the endoscope handle 2. In case of the first braking mechanism, the corresponding (first) cam surface unit 19a is supported on the central shaft 8, i.e. via a spline structure as shown in FIG. 3. In case of the second braking mechanism, the corresponding (second) cam surface unit 19b is supported on a pipe-like protrusion of the endoscope handle 2. Via the spring 15a, 15b, the cam surface is pushed towards a (selectively first or second) cam 20a, 20b formed by the braking control element 7a, 7b. When the braking control element 7a, 7b is rotated, the cam 20a, 20b is moved in a circumferential direction and slides along the cam surface, such that a circumferential movement of the cam 20a, 20b is transformed into an axial movement of the cam surface unit 19a, 19b.

[0063] That is, when the braking mechanism is in a non-activated state, as shown in FIGS. 3 and 5, the clip-in arms 18a, 18b of the pressurizing element 16a, 16b contact the rim of the steering control element 6a, 6b. The cam surface unit 19a, 19b can now move axially between the cam 20a, 20b and the stack of friction discs 17a, 17b by a clearance c and the friction discs are not pressed against each other.

[0064] Then, when the braking control element 7a, 7b including the cam 20a, 20b is rotated, the cam 20a, 20b pushes the cam surface unit 19a, 19b against the spring 15a, 15b towards the pressurizing element 16a, 16b. The spring 15a, 15b is compressed and a clearance c between the clip-in arms 18a, 18b of the pressurizing element 16a, 16b and the rim of the steering control element 6a, 6b occurs. Thus, as shown in FIGS. 4 and 6, the stack of friction discs 17a, 17b is compressed between the pressurizing element 16a, 16b and the cam surface unit 19a, 19b by a force of the spring 15a, 15b. A frictional fit between the brake-side friction discs and the steering-side friction discs is provided. The braking mechanism is activated.

[0065] When the braking control element 7a, 7b is rotated towards a non-activated position in order to loosen the braking mechanism, the cam 20a, 20b slides along the cam surface, releasing the cam surface unit 19a, 19b. As a result, the friction fit assembly 14a, 14b is pushed out of the steering control element 6a, 6b until the clip-in arms 18a, 18b of the pressurizing element 16a, 16b contact the rim of the steering control element 6a, 6b. Then, the force of the spring 15a, 15b does not act on the stack of friction discs 17a, 17b anymore, releasing the frictional fit between the brake-side friction discs and the steering-side friction discs.

[0066] Further, the first braking mechanism and the second braking mechanism provide different (selectively first or second) tactile structures 21a, 21b, which respectively define one or more intermediate braking positions.

[0067] In the first braking mechanism, the corresponding (first) tactile structure 21a is provided on the corresponding (first) cam surface. In this specific embodiment, as best seen in FIG. 7, the corresponding (first) cam surface unit 19a forms three first cam surfaces, adapted to contact the corresponding (first) cam 20a. Said first cam 20a is formed by the first braking control element 7a, as shown in FIG. 4. Each first cam surface essentially extends along a third of a circumference of the corresponding (first) cam surface unit 19a. Each first cam surface 20a subsequently has a first flat section 22, a first ramp section 23 extending circumferentially and axially towards the first braking control element 7a, an intermediate section 24 forming a recess in the first cam surface, a second ramp section 25 and a second flat section 26. The first flat section 22 and the second flat section 26 extend essentially orthogonally with respect to the control axis 9. The intermediate section 24 forms a first shoulder adjacent to the first ramp section 23. Preferably, adjacent to the second ramp section 25, the intermediate section 24 further forms a second shoulder, i.e. a surface having a steeper angle with respect to the circumferential direction than the second ramp section 25. In FIG. 8, which shows a partial sectional side view of the first braking mechanism, a state where the first braking control element 7a is positioned such that the first cam 20a contacts the intermediate section 24 of the first cam surface is illustrated.

[0068] Further, as seen in FIG. 7, the first cam surface unit 19a forms at least one, particularly three, circumferentially and axially extending stopper grooves 27 providing two circumferential stopper surfaces. Axially extending stopper pins 28 are formed integrally with the first braking control element 7a and, as shown in FIGS. 3 and 4, are received in said circumferentially extending grooves 27 to be slidable in the axial direction and in the circumferential direction. Thus, a relative rotation between the first braking control element 7a and the first cam surface unit 19a (and therefore the endoscope handle 2), is limited by a contact of the stopper pins 28 with the stopper surfaces of the stopper grooves 27. Further, the first braking control element 7a is formed integrally with the first cam 20a or cams (a number of cams corresponds to a number of cam surfaces), which extends axially towards the first cam surface unit 19a, having inclined or tapering contact edges. In particular, the first cam 20a is formed near a circumferentially inner surface of the first braking control element 7a.

[0069] A second tactile structure 21b provided by the second braking mechanism is described via the schematic side view shown in FIG. 9. In detail, FIG. 9 schematically shows an endoscope handle 2, provided with bumps or ribs serving as the second tactile structures 21b. The second braking control element 7b is supported on the endoscope handle 2 and has a lever portion 29. The lever portion 29 serves as a spring arm 35 and, facing towards the endoscope handle 2, forms a clicking structure 30 adapted to resiliently engage the second tactile structure 21b. On a side opposite to the clicking structure 30, the second braking control element 7b forms the second cam 20b. The second cam surface of the second cam surface unit 19b contacts the second cam 20b in the axial direction.

[0070] In the upper portion of FIG. 9, the second braking control element 7b is in an off-position and the lever portion 29 contacts a stopper flank 31 formed by the endoscope handle 2. In this position, the second cam 20b contacts a first flat surface 32 of the second cam surface, minimizing a distance between a friction element facing side of the second cam surface unit 19b and the second braking control element 7b. Thus, the second braking mechanism is inactive. In the lower portion of FIG. 9, the second braking control element 7b has been rotated to a first intermediate braking position. The clicking structure 30 formed on the lever portion 29 now engages a first bump or rib serving as one of the second tactile structures 21b of the second brake mechanism. The second cam 20b has slid approximately halfway along a ramp section 33 of the second cam surface unit 19b. Thus, the second cam surface unit 19b is pushed halfway towards the second friction element 17b, providing an intermediate braking force. The ramp section 33 of the second cam surface unit 19b has a continuous, linear ramp surface.

[0071] The structure of the second braking mechanism can also be seen in FIG. 10. In particular, in this view, an alternative structure of the clicking structure 30 is shown. Slots cut into a base portion 34 of the second braking control element 7b define flanks of a spring arm 35. On a lower side of the spring arm 35, the clicking structure 30 is formed as a bump extending towards the endoscope handle 2. When the bump or clicking structure 30 slides over an obstacle, the spring arm 35 will evade said obstacle and bend away from the obstacle. This is the case e.g. when the second braking mechanism is mounted to the endoscope handle 2 shown in FIG. 11, with the bumps or ribs (i.e. the second tactile structure 21b) serving as the obstacle. The bump-shaped clicking structure 30 formed at the second braking control element 7b slips between the bumps or ribs serving as the second tactile structure 21b and defining several intermediate braking positions. The second tactile structure 21b is formed on a supporting surface of the endoscope handle 2 housing which is recessed with respect to a surrounding housing part of the endoscope handle 2 in order to receive and support the second braking control element 7b as shown in FIG. 12 in a plan view. As shown in FIG. 11, diametrically opposite to the second tactile structure 21b, the supporting surface of the endoscope handle 2 opens at an angle in order to accommodate the lever portion 29 of the second braking control element 7b. Circumferential flanks next to the portion of the supporting surface of the endoscope handle 2 opening at an angle form the stopper flanks 31 adapted to contact the lever portion 29 laterally, thus limiting a rotation of the second braking control element 7b between the two stopper flanks 31. FIG. 11 further shows that the second braking control element 7b forms three second cams 20b.

[0072] As mentioned above, the braking mechanisms have tactile structures defining an intermediate braking position which is neither a full-braking position nor a non-braking position. Thus, in the intermediate braking position, the friction element is translated only partially along the control axis. The tactile structure may be any structure which provides a tactile feedback to the user that the intermediate braking position has been reached. The tactile structure can be a recess or a protrusion between the first and second ramp sections. The recess allows the cam to change the feedback provided as the control is rotated, as the cam dips into the recess. Alternatively, a protrusion between the first and second ramp sections would interrupt the rotation of the control momentarily, changing the force required for the cam to pass over the protrusion, thus providing tactile feedback. In the embodiment described with reference to FIG. 9 the clicking structure 30 resiliently engages the second tactile structure 21b, illustrated by a pair of bumps or ribs. Each of the bump or ribs generates a click therefore there are two intermediate brake positions. More or less bumps or ribs may be provided. The bumps or ribs can, alternatively, be positioned on the lever portion with the clicking structure formed in the handle. The intermediate section can be said to comprise the first and second ramp sections, where the bump or rib is aligned with a gap between them, even though the bump or rib is not placed on the intermediate section.

[0073] The following items are examples of various embodiments and variations thereof disclosed above, and others:

[0074] 1. An endoscope (1) comprising: a proximal endoscope handle (2); an insertion cord extending from the endoscope handle (2) and configured to be inserted into a patient's body cavity, the insertion cord comprising an insertion tube (3), a bending section (4) and a distal tip unit (5); a steering mechanism configured to swivel the distal tip unit (5) by bending the bending section (4), and a braking mechanism configured to brake the steering mechanism,

[0075] the steering mechanism comprising: a manually operable steering control element (6a), which is provided for receiving a steering input by a user and is rotatable around a control axis (9), and at least one steering wire (12a), which connects the bending section (4) with the steering control element (6a), and

[0076] the braking mechanism comprising: a manually operable braking control element (7a) provided for receiving a braking input by the user, a friction element (17a) which is axially translatable in an axial direction defined by the control axis (9) to engage or disengage with the steering mechanism, and a cam pairing having a cam surface unit (19a) forming a cam surface and a cam (20a) contacting the cam surface in the axial direction, the cam (20a) being connected to or integrally formed with one of the braking control element (7a) and the friction element (17a) and the cam surface unit (19a) being connected to or integrally formed with the other one of the braking control element (7a) and the friction element (17a), the cam (20a) being configured to slide along the cam surface to transform the braking input into an axial translation of the friction element (17a), wherein the cam surface forms a first ramp section (23) for translating the friction element (17a) from a first braking position to an intermediate braking position, a second ramp section (25) for translating the friction element (17a) from the intermediate braking position to a second braking position, and an intermediate section (24) forming a tactile structure (21a), being arranged between the first ramp section (23) and the second ramp section (25) and defining the intermediate braking position.

[0077] 2. The endoscope (1) according to item 1, wherein the braking control element (7a) is rotatable around the control axis (9), the cam surface extends in a circumferential direction and the first ramp section (23) and the second ramp section (25) extend in the circumferential direction and in the axial direction.

[0078] 3. The endoscope (1) according to item 2, wherein at least two, preferably three, cam surfaces are provided, which are dimensioned and arranged to form a circle around the control axis (9).

[0079] 4. The endoscope (1) according to one of items 1 to 3, wherein the intermediate section (24) forms a projection and/or a recess at least with respect to the first ramp section (23).

[0080] 5. The endoscope (1) according to one of items 1 to 4, wherein the intermediate section (24) forms a first shoulder or step adjacent to the first ramp section (23), a second shoulder or step adjacent to the second ramp section (25) and an intermediate flat surface arranged between the first shoulder or step and the second shoulder or step, with the first shoulder or step preferably having a steeper inclination than the second shoulder or step.

[0081] 6. The endoscope (1) according to one of items 1 to 5, wherein the cam surface forms a first flat surface (22) at a position corresponding to the first braking position and/or a second flat surface (26) at a position corresponding to the second braking position.

[0082] 7. The endoscope (1) according to one of items 1 to 6, wherein the first ramp section (23) and the second ramp section (25) have essentially the same inclination and a reference line extending from the first ramp section (23) is essentially tangential to the second ramp section (25) adjacent to the intermediate section (24).

[0083] 8. The endoscope (1) according to one of items 1 to 7, wherein the cam (20a) is non-rotatably connected to the braking control element (7a) or formed integrally with the braking control element (7a), preferably on an inner axial or circumferential surface thereof.

[0084] 9. The endoscope (1) according to item 8, wherein the cam (20a) has a contact edge which tapers in a direction towards the cam surface unit (19a).

[0085] 10. The endoscope (1) according to one of items 1 to 9, wherein a pressurizing element (16a) is provided which supports a spring element (15a) on one axial side and the frictional element (17a) on another axial side, and the pressurizing element (16a) forms a stop surface (18a) acting in a direction opposite to the spring element (15a) and adapted to contact a rim portion of the steering control element (6a).

[0086] 11. The endoscope (1) according to one of items 1 to 10, wherein the braking control element (7a) and the cam surface unit (19a) engage with each other via a circumferential stopping structure including a circumferentially extending stopper groove (27) providing two circumferential stopper surfaces and an axially extending stopper pin (28) which are slidable with respect to each other in the axial direction and in the circumferential direction.

[0087] 12. The endoscope (1) according to one of items 1 to 11, further comprising

[0088] a second steering mechanism configured to swivel the distal tip unit (5) by bending the bending section (4) in a second direction, comprising a second manually operable steering control element (6b), which is provided for receiving a second steering input by the user and is rotatable around the control axis (9), and at least one second steering wire (12b), which connects the bending section (4) with the second steering control element (6b), and

[0089] a second braking mechanism configured to brake the second steering mechanism and comprising:

[0090] a manually operable second braking control element (7b) provided for receiving a second braking input by the user and being rotatable around the control axis (9),

[0091] a second friction element (17b) which is axially translatable in the axial direction to engage or disengage with the second steering mechanism, and

[0092] a second cam pairing having a second cam surface unit (19b), which forms a ramp section (33) of the second cam surface unit (19b), and a second cam (20b) contacting the ramp section (33) of the second cam surface unit (19b) in the axial direction, the second cam (20b) being connected to one of the second braking control element (7b) and the second friction element (17b) and the second cam surface unit (19b) being connected to the other one of the second braking control element (7b) and the second friction element (17b), the second cam (20b) being configured to slide along the ramp section (33) of the second cam surface unit (19b) to transform the second braking input into an axial translation of the second friction element (17b),

[0093] wherein the second braking control element (7b) and a portion of the endoscope handle (2) form a click interface, said click interface including a click recess or click protrusion as a clicking structure (30), which is formed at one of the second braking control element (7b) and the portion of the endoscope handle (2), and a spring arm (35), which is formed at the other one of the second braking control element (7b) and the portion of the endoscope handle (2), is configured to engage with said clicking structure (30) and to resiliently bend away from said clicking structure (30).

[0094] 13. The endoscope (1) according to item 12, wherein the second braking control element (7b) has a plate-like base portion (34), which forms the second cam surface or the second cam (20b) facing towards one side and which forms the spring arm (35) facing towards an opposing side.

[0095] 14. The endoscope (1) according to item 13, wherein the spring arm (35) is formed from the base portion (34) of the second braking control element (7b) in the manner of a bridge formed between two longitudinal slits.

[0096] 15. System comprising an endoscope (1) according to one of the items 1 to 14 and a monitor (M) connectable to the endoscope (1).

LIST OF REFERENCE NUMBERS

[0097] 1 endoscope

[0098] 2 endoscope handle

[0099] 3 insertion tube

[0100] 4 bending section

[0101] 5 distal tip unit

[0102] 6a, 6b first and second steering control elements

[0103] 7a, 7b first and second braking control elements

[0104] 8 central shaft

[0105] 9 control axis

[0106] 10 hollow shaft

[0107] 11a, 11 b first and second wire drums

[0108] 12a, 12b first and second steering wires

[0109] 13 intermediate support portion

[0110] 14a, 14b first and second friction fit assemblies

[0111] 15a, 15b first and second springs

[0112] 16a, 16b first and second pressurizing element

[0113] 17a, 17b first and second stacks of friction discs/friction elements

[0114] 18a, 18b first and second clip-in arms/stop surfaces

[0115] 19a, 19b first and second cam surface units

[0116] 20a, 20b first and second cams

[0117] 21a, 21b first and second tactile structures

[0118] 22 first flat section of the first cam surface

[0119] 23 first ramp section of the first cam surface

[0120] 24 intermediate section of the first cam surface

[0121] 25 second ramp section of the first cam surface

[0122] 26 second flat section of the first cam surface

[0123] 27 stopper groove(s)

[0124] 28 stopper pins

[0125] 29 lever portion

[0126] 30 clicking structure

[0127] 31 stopper flank

[0128] 32 first flat surface of the second cam surface

[0129] 33 ramp section of the second cam surface unit

[0130] 34 base portion

[0131] 35 spring arm