27, 28 by having a first hook 30 for attachment of a loop formed by an end section of the first steering wire 27, and a second hook 31 for attachment of a loop formed by an end section of the second steering wire 28. End sections of the first steering wire and the second steering wire are preferably not connected in the handle. The first and second steering wires extend through the insertion cord to a fixed connection to the distal end of the insertion cord, at the segment 21 of the bending section 20 or to the tip housing. The roller may be injection molded in one part from a polymer material, such as for example POM, PP or HDPE.

For this disclosure one steering wire is counted as one passage from the steering wire actuator to the distal end of the bending section. I.e. if the same unbroken steering wire continues from the distal end of the bending section and back to the steering wire actuator, and one part is applied for bending, for example, to one side and the other is applied for bending to the opposite side, this is counted as two steering wires, e.g. first and second steering wires 27, 28. Also, when distal wire ends are not attached to each other but each is connected to the distal end of the bending section or the tip part, this is also counted as two steering wires, e.g., first and second steering wires.

The roller 32 may comprise a first plate 34 having a first surface 36 on which the first hook 30 is arranged and a second plate 35 having a second surface 37 on which the second hook 31 is arranged. The first and second plates 34, 35 may be arranged in two different, but parallel or substantially parallel, planes displaced, or offset, by a distance d, where d is preferably in the range 2-7 mm, and more preferably in the range 3-5 mm. Preferably, there will be a similar displacement between the first and second surfaces 36, 37.

The displacement between the first and second surfaces 36, 37 ensures that if the steering wires cross between the roller and the wire pipe fastener 70, they will not rub against each other when manipulating the roller 32 to bend the bending section 20. Furthermore, the first plate 34 of the roller may be limited by the positioning of the attached arcuate cover surface 43, which may be aligned with the slit in the handle 2 for the bending lever 46. The second plate 35 of the roller may, however, be displaced to a position leaving space for other parts inside the handle, for example suctioning tube or valves. However, the maximum rotation of the roller may limit how much space such other parts can use without conflicting with the first plate 34 of the roller and the arcuate cover surface 43 during rotation of the roller 32.

As seen in FIGS. 4A-4C, the wire drum curved surface 61 for the first steering wire 27 is arranged to extend perpendicular from the first surface 36, and the wire drum curved surface 61′ for the second steering wire 28 is arranged to extend perpendicular from the second surface 37.

Also, the wire drum curved surfaces 61, 61′ are placed close to the periphery of the first and second plates 34, 35 of the roller 32, but so that the peripheral part of the plates 34, 35 may function as a supportive wall for guiding the steering wires 27, 28 when placed on the wire drum curved surfaces 61, 61′. In other words, the first and second plates 34, 35 may extend radially outwardly further than the wire drum curved surfaces 61, 61′ to aid in the threading of the wires and to keep the wires from slipping off the wire drum curved surfaces 61, 61′. Further to this, the wire drums may be provided with a further supportive guiding wall 33, at least along a part of the wire drum curved surfaces 61, 61′. This guiding wall should be placed opposite to the first and second plates 34, 35, respectively, thereby forming a groove like passage 51 for the steering wire 27, 28.

There may be some distance between the wire drum curved surfaces 61, 61′ and the corresponding hook 30, 31 on the first and second surfaces 36, 37, respectively. A support pin 49 may extend from the first and second surfaces 36, 37 between the wire drum curved surfaces 61, 61′ and the corresponding hook 30, 31. This support pin 49 may prevent that the steering wire 27, 28 is unintentionally removed from the groove 51 during rotational movements of the roller 32 for bending of the bending section. These movements imply that the steering wires 27, 28 are alternately pulled and loosened. When a steering wire is loosened, it should not be possible for it to leave or slip out of the groove 51. Such removal can be prevented by the support pin 49, when the steering wire 27, 28 passes the support pin 49 on the side pointing towards a center of the roller (the radially inwardly facing side). The center of the roller may be similar to a center axis c passing through the passage 44 for a shaft 45 for the roller 32.

FIGS. 4C and 5A show that the hook 30, 31 may comprise a base part 38 extending perpendicular to the first or second surface 36, 37 of the roller. The hook further comprises a holding part 39 extending from the base part 38 in parallel with, or substantially in parallel with, the first and second surfaces 36, 37 of the roller 32. FIG. 5B shows the hook from the other side of the first or second plate 34, 35 of the roller 32, i.e., the side opposite to the surface 36, 37 from where the base part 38 of the hook is extending. Here, it is seen that the first and second plates 34, 35 may be provided with a hole 52 at the positions where the holding parts 39 of the first and second hooks 30, 31 are projected on the first and second surfaces 36, 37, respectively. One advantage of the hole 52 is that the roller 32 may be designed for a simple one-shot injection molding manufacturing. As seen in FIG. 5B, the hole 52 is also slightly larger than the holding part 39 of the hook 30, 31.

As indicated in FIGS. 5A and 5B, the hole 52 below the holding part 39 of the hook 30, 31 is longer than the holding part 39, when measured from the base part 38 to the point of the hole 52 and of the holding part 39 furthest away from the base part 38. It has been found that this makes it easier to arrange the loop of the steering wire 27, 28 to the hook during manufacturing, as more space will be available for a pair of tweezers to maneuver the loop of the steering wire 27, 28 into position at the hook 30, 31. To achieve this, the hole 52 may be at least 0.5 mm longer than the length of the holding part. The length of the holding part 39 and the hole 52 is measured from the base part 38 and in a direction away from the base part, e.g., the part of the holding part 39 furthest away from the base part. As shown, the holding part 39 extends from the base 38 in a circumferential direction away from the respective guiding wall 61, 61′, with a respective support pin 49 between the base and the guiding wall 61, 61′. Additionally, the most inward facing surface of the support pin 49 is radially outward relative to the most inward facing surface of the base 38. Furthermore, the most inward facing surface of the support pin 49 is radially inward relative to the groove 51. A circumferentially extending gap 38′ can be seen between the base 38 and the support pin 39. The steering wire passes through this gap 38′.

The base part 38 of the hook 30, 31 each comprises a receiving surface 53 for supporting the closed loop of the steering wire 27, 28. The receiving surface may be provided with a curvature having a radius of at least 1 mm, preferably at least 1.5 mm, where a part of the looping steering wire follows this curved receiving surface 53. The pulling force transferred from the roller 32 to a steering wire 27, 28, is transferred through this curved receiving surface 53. The advantage of having the receiving surface 53 curved is that this makes adjustment of the steering wire easier during assembly of the endoscope. Here, the roller is fixated in a neutral position and the bending section is straight, i.e., not bent. A steering wire closed loop is formed and arranged in the hook 30, 31, and the steering wire free end is led back in parallel with the steering wire. In this position of roller, bending section and steering wires, the tension on each steering wire 27, 28 is adjusted to a preselected value before attaching the free end of the steering wire to the same steering wire, e.g. by crimping or gluing.

The tension on each steering wire 27, 28 is adjusted by pulling the free end of the looped steering wire with a well-defined preselected force. Thereby, the steering wire 27, 28 will slide on the receiving surface 53 until a balance with the correct tension on the steering wire is achieved. Attaching the free end of the steering wire to the same steering wire is done while keeping the tension on the steering wire. This procedure is performed for both steering wires.

FIGS. 6A and 6B show a variation where the holding part 39 of the hook is provided with a barb 54 for keeping the looped steering wire 27, 28 attached to the hook 30, 31 during manipulation of the roller 32 for bending the bending section 20, during which the steering wire not being pulled may be loosened. The presence of the barb 54 may replace the functionality of the support pin 49 or make the support pin less necessary. Also, the barb 54 may be provided with an inclined surface 55 which may make it easier to arrange the looped steering wire, i.e., the steering wire closed loop in the hook during assembly. The inclined surface extends from the free end of the holding part (the end away from the base) toward the plate and the base. In another example, both the support pin 49 and the barb 54 are provided.

FIG. 7 shows a roller as in FIGS. 4A-4C, with two steering wires attached. Each steering wire 27, 28 is looping around a separate hook 30, 31, preferably by first forming a closed loop of the steering wire free end, and then attaching the closed loop to the hook by drawing the steering wire in between the holding part 39 of the hook and the corresponding first or second surface 36, 37 of the roller. Each steering wire 27, 28 is attached to itself by application of a crimp 63. Each steering wire is guided in its corresponding groove 51, i.e., the first steering wire is guided on the first surface 36 of the roller 32 by the groove 51 and the support pin 49 and looping around the first hook 30. The second steering wire is guided on the second surface 37 of the roller 32 by the parts on the second surface, i.e., the groove 51 and the support pin 49 and looping around the second hook 31. The steering wires may be made from stainless steel and may have a diameter in the range 0.15-0.35 mm. The proximal ends of the steering wires are looped around the barbed hooks shown in FIGS. 6A and 6B in the same manner.

FIG. 8 shows one shell part 56 of the handle. This shell part is provided with a shaft 45 for the roller 32. The shaft 45 may be molded as part of the handle shell part 56 but could also be connected to the handle shell part after molding. As seen in FIG. 8, the roller 32 is arranged to the shaft 45 such that the roller can be rotated to some extent by movement of the bending lever 46. This rotational movement will pull one of the steering wires 27, 28, depending on the direction of the rotation, and the other steering wire 27, 28 will be relaxed. In FIG. 8 the steering wires are connected to the roller 32 as shown and described with reference to FIG. 7.

In an example of the roller 32 including the first and second wire drum curved surfaces 61, 61′ and the first and second hook 30, 31, an outer diameter of the roller, perpendicular to the center axis c, is 40-45 mm. The passage 44 for a shaft has a diameter of 11-13 mm. The radius of the receiving surface 53 of the base part 38 of the hook is 1.5-2 mm. The holding part 39 of the hook has a length of 7-8 mm and a width of 3.4-3.7 mm. The thickness of the holding part is 0.75-0.9 mm, and the distance between the surface of the roller 36, 37 and the holding part 39 is around 0.6 mm, measured in a direction perpendicular to the surface of the roller. The hole 52 in the surface of the roller below the holding part 39, has a length of 9-10 mm and a width of 3.9-4.2 mm. The area of the holding part 39 of the hook may be 27-30 mm². The area of the hole 52 below the hook may be 36-40 mm². The displacement between the first surface of roller 36 and the second surface of roller 37 measured along the center axis c is 3.4-3.6 mm. The thickness of the first and second plates 34, 35 of the roller are 1-1.5 mm.

In this disclosure the handle 2 may be a positioning interface, or interface, which functions to control the position of the insertion cord 3. The handle 2 is an example of a positioning interface and, unless stated otherwise, the terms are used interchangeably. The positioning interface also functions to provide the steering controls, e.g. knobs, levers, buttons, and the like, used to steer the tip of the insertion cord 6, which includes the camera, and the elevator controls. Alternatively, a different positioning interface can be provided that is connected to the insertion cord and is detachably connected to a robotic arm. In a further alternative, the positioning interface is detachably connected to the insertion cord and is therefore reusable. In this example the positioning interface may be affixed to a robotic arm. The insertion cord thus extends from the robotic arm, and the intrusive medical device is detachable from the robotic arm. The robotic arm responds to signals, including voice commands from an operator, to rotate, translate, and otherwise position the proximal end of the insertion cord, as an operator would do manually. The positioning interface can include control actuators, including manual control actuators. Alternatively, or additionally, control actuators can be provided in or on the robotic arm or by the robotic system including the robotic arm, thereby potentially reducing the cost of the intrusive medical device. Example control actuators include single axis actuators, including linear motion actuators. A linear motion actuator may comprise a threaded rod coupled to a threaded nut portion, in which a motor rotates the rod to translate the nut portion.