Patent Description:
In general, an endoscope comprises an operating handle at the proximal end and an insertion cord extending from the handle towards the distal end. The handle is adapted to be held by an operator and inter alia comprises externally protruding operating members connected to internal control gear allowing the operator to control the movement of a controllable bending section at the distal end of the insertion cord, while advancing the distal end of the insertion cord to a desired location e.g. within a body cavity of a person. By means of an attached monitoring device, such as a monitor with a display screen, the location to which the distal end has been advanced may be inspected using the endoscope.

The controllable bending section is normally an articulated section at the distal tip of the insertion cord that can be controlled by the operator from the handle, allowing the operator to advance the distal tip of the endoscope to a desired location by means of a series of actions involving inter alia bending the bending section in a desired direction, advancing the insertion cord and turning the insertion cord by turning the handle which is rigidly connected thereto. Having negotiated a tortuous path of bends and turns to a location of interest, the operator may end up in an awkward or ergonomically unfavourable body position.

This drawback may be overcome if the insertion cord is not rigidly connected to the handle, but may be turned with respect thereto. This allows the operator to turn the handle into a more convenient and ergonomically favourable position once the insertion cord is in place. It will also allow for an additional degree of freedom because the operator may choose to turn only the insertion cord rather than both the handle and the insertion cord when navigating during insertion.

In this respect <CIT> discloses an endoscope with a handle and an insertion cord that may be turned between a number of fixed latching positions with respect to the handle. There are no means to prevent turning the insertion cord too much with respect to the handle, just as statement that it should not be turned more than <NUM>° in order not to break the inner workings i.e. the cables etc. running from the handle into the insertion cord. <CIT> also discloses an endoscope with a handle and an insertion cord that may be turned with respect to the handle. The turning angle is limited by a stop so as not to twist and damage the fibre bundle running from the handle into the insertion cord when turning the insertion cord with respect to the handle. <CIT> discloses an endoscope according to the preamble of claim <NUM>. <CIT> discloses an endoscope with an inner rotating cylinder positioned in the middle of the insertion section.

In recent years single use or disposable endoscopes that are used on one patient only before being thrown away have gained substantially in popularity as compared to traditional endoscopes that were reused after difficult and costly cleaning and sterilisation. Evidently, if an endoscope is single use it needs to be manufactured in a cost-efficient manner, meaning that the constituent parts should have low cost, and that the assembly thereof should be simple so as not incur unnecessary time consumption.

In this respect, the prior art couplings do not render themselves to cost-efficient assembly as it will be difficult to thread the flexible bundle of e.g. electrical supply wires and signals cables, pull wires, optical fibres, etc. forming part of a sub-assembly though these coupling mechanisms between the handle and the insertion cord.

Moreover, in use, the coupling should give the operator good tactile feedback. That is to say sufficient friction to avoid inadvertent turning of the insertion cord but not so much that it prevents smooth manipulation by the average operator.

Also, the cable bundle should be protected from damaging from e.g. twisting the insertion cord too much with respect to the handle.

Based on this it is the object of providing an endoscope having an insertion tube that may be turned with respect to the handle, and at the same time overcomes the above drawbacks.

According to the invention as defined in claim <NUM>, this object is achieved by an endoscope comprising a proximal handle comprising a housing part and a distal insertion cord coupled to said proximal handle by means of a rotary coupling mechanism allowing rotation about a rotation axis, said coupling mechanism comprising a bushing having a through aperture defining an inner bushing wall surface adapted to receive a connection member and an outer bushing wall surface adapted to engage an inner handle surface in said handle, a connection member received in said through aperture and having a wall defining a through passage between a first end and a second end, wherein said second end is attached to an insertion cord sub-assembly, and said first end is rotatably coupled to a working channel part within said handle, wherein a lateral exit opening is provided in said wall between said first end and said second end comprises, and wherein a slit is provided in said wall from said second end to said exit opening.

This strongly facilitates the assembly of the endoscope because the entire insertion cord may be made or prefabricated as a separate insertion cord subassembly with all cables and wires extending from the proximal end. When attaching the proximal end of the insertion cord subassembly to the connection member the cables and wires need not be passed axially through any ports or apertures, but may just be passed laterally through the slit and emerge from the lateral exit opening. In other words, the cables and wires need not be threaded with the entire length with which they extend from the proximal end of the insertion cord subassembly through an eyelet. Rather, only a short length of the wires and cables need to be passed laterally through the slit which is a far easier procedure.

According to a preferred embodiment of the invention, the inner bushing wall surface comprises a rib protruding into said slit. Once the bushing has been passed over the insertion cord from the distal end this rib closes the slit in the connection member and keep the cables and wires centred between the distal end of the connection member and the lateral exit opening.

According to an embodiment of the invention, the coupling mechanism further comprises an annular gripping member having an external circumferential gripping surface and an inner gripping member surface, where the inner gripping member surface comprises a first inner gripping member surface part in engagement with said outer bushing wall surface and a second inner gripping member surface part rotatably engaging the exterior of said housing part. This allows a firm grip on the rotary part without having to grip the bushing wall itself which would normally be made of a low friction material less suitable for gripping.

According to an embodiment of the invention, the endoscope further comprises a locking clip securing said bushing against axial motion with respect to the housing part along said rotation axis.

According to an embodiment the locking clip is made from the same material as the bushing, so as to keep friction low.

According to an embodiment of the invention, the second inner gripping member surface part comprises at least one position reference member adapted to mutually engage a complementary position reference member on the exterior of said housing part. This allows for temporary rest in a neutral centre position and tactile feedback to the operator when moving from the neutral centre position.

According to a further preferred embodiment of the invention, the complementary position reference member is provided on a spring member provided integrally with the housing part, said spring member extending in a circumferential direction at the distal end of the housing part.

The disclosure will now be made in greater details based on non-limiting exemplary embodiments and with reference to the drawings, on which:.

Turning first to <FIG> a system comprising an endoscope <NUM> and a display unit <NUM> is shown. The endoscope <NUM> may be connected to the monitor <NUM> by means of a cable <NUM> with a suitable connector <NUM>. The endoscope <NUM> is preferably disposable i.e. intended to be thrown away after use on one single patient, whereas the display device <NUM> may be used multiple times with different reusable endoscopes. The endoscope is an insertion endoscope comprising a handle <NUM> at the proximal end, and an insertion cord <NUM> extending from the handle <NUM> towards the distal end of the endoscope <NUM>. At the distal end of the insertion cord <NUM> a bending section which may be controlled by an operating member <NUM> is provided. As can be seen from <FIG> and <FIG> the bending section comprises a bending section body <NUM> beneath a flexible cover 7a. In turn at the distal end of the bending section <NUM> a tip housing <NUM> with the image capture device, lenses, illumination, the distal port of a working and/or suction cannel etc. of the endoscope is provided. At the distal end the working channel will normally serve dual functions as both working channels for tools and suction channel. The handle <NUM> normally also comprises a suction activation button <NUM> for activating the suction though the suction channel to an external vacuum source (not shown) via a suction connector <NUM>. The handle may also have a tool insertion port <NUM> (cf. <FIG>) with a cap 12a for the insertion of an external tool through the handle and the working channel so as to emerge from the distal working channel port at the tip housing <NUM>. Also, the handle <NUM> may be provided with buttons for activation electrical switches <NUM> controlling function of the image capture, such as taking of still images. In accordance with the present disclosure the insertion cord <NUM> may be rotated with respect to the handle <NUM> by manually gripping and turning a gripping surface <NUM> associated with a coupling mechanism which will be describe below.

Turning now to <FIG>, <FIG> and <FIG> the components of the exemplary embodiment of the endoscope <NUM> are shown in exploded view. In <FIG> the components of the handle <NUM>, the coupling mechanism as well as the connection cable <NUM> are shown. In <FIG> the components of the insertion cord sub-assembly are shown. These include the tip housing <NUM> attached to the bending section body <NUM> which is in turn connected to the main tube 6a forming the majority of the body of the insertion cord <NUM>. Inside the main tube 6a a working channel tube <NUM> is provided. The working channel tube <NUM> passes through the bending section body <NUM> and is attached to the tip housing <NUM>, more specifically so attached that it is in communication with a passage through the tip housing <NUM> to a distal working channel port. Electrical wiring <NUM> to the image capture device <NUM> also run along the inside of the main tube 6a, through the bending section body <NUM> and into the tip housing <NUM> where the image capture <NUM> device is accommodated. Likewise, the supply cables for the illumination components such as LEDs run along the inside of the main tube 6a, through the bending section body <NUM> and into the tip housing <NUM> where also the illumination components are accommodated. Similarly, the pull wires <NUM> for bending the bending section body <NUM> run along the inside of the main tube 6a and through the bending section body <NUM>. To avoid ingress of water or the like the bending section body <NUM> is covered by a flexible cover 7a connected to the tip housing <NUM> and the main tube 6a in a sealed manner. A stabilizer <NUM> may also be accommodated in the main tube 6a. All these parts may be preassembled and the electrical wiring <NUM> and supply wires preferably also connected to a circuit board <NUM>, as shown in <FIG> to provide a pre-assembled sub-assembly to be joined with the handle <NUM>, in a subsequent assembly step when assembling the endoscope <NUM>. As can be seen the electrical wiring <NUM>, supply cables and pull wires <NUM> as well as the printed circuit board <NUM> extend from the sub-assembly. Accordingly, the handle <NUM> and the coupling mechanism according to the disclosure have been adapted for easy assembly despite these extending parts.

Turning now to <FIG> a handle housing part <NUM> is shown. The handle housing part <NUM> comprises a shell shape adapted for accommodating internal parts of the handle and is covered by a lid <NUM>, cf. e.g. <FIG>, which is also somewhat shell-shaped. The handle housing part <NUM> serves as a base for supporting most of the internal parts accommodated in the handle <NUM>, whereas the lid <NUM> essentially only serves as a closing cover. That is to say, the cover holds the operating member (8a), the anchoring block <NUM> for the guide tubes guide tubes 19a, a PCB <NUM> and the C-shaped clip <NUM> in position, but does preferably not carry or support any internal parts apart from that. As can be seen, the distal handle housing end <NUM> is C-shaped in circumference, with a longitudinal slit <NUM>. As will be elaborated below, the distal handle housing end <NUM> is adapted for form part of a rotary coupling mechanism allowing the insertion cord <NUM> of the insertion cord sub-assembly (shown in <FIG>) to be turned with respect to the handle <NUM>. The handle housing part <NUM> also comprises an opening <NUM> adapted to receive the suction connector <NUM> for connecting the partially combined suction and working channel to an external vacuum source. The partially combined suction and working channel comprises a Y-junction body <NUM> comprising a tool entry port <NUM> located in a further opening <NUM> in the handle housing part <NUM>. A further opening (not visible) may be provided in the handle housing part <NUM> to accommodate a suction activation valve assembly 10a, 10b, 10c, 10d, associated with the suction activation button <NUM> and connected to the suction connector <NUM>. The suction activation valve assembly 10a, 10b, 10c, 10d is furthermore connected to one end of an intermediate suction tube <NUM>, the other end of the intermediate suction tube <NUM> being connected to the Y-junction body <NUM>, e.g. in a receptacle <NUM> formed in one branch of the Y-junction body <NUM>, as indicated in <FIG>. The Y-junction body <NUM> may be integrally formed but for manufacturing reason is preferably provides in two pieces, i.e. including a Y-junction lid 25a, with a guiding surface 25b facilitating the insertion of a tool from the tool port.

The working channel tube <NUM> located in the centre of the main tube 6a needs to be rotatable with respect to the distal end of the Y-junction body <NUM> which is fixed withing the handle <NUM>. Pull wires <NUM>, at least partially, need to be located off-centre to function. In any case, pull wires <NUM>, electrical wiring <NUM> and supply cables for the LEDs cannot coincide with the working channel tube <NUM>, and therefore must also be accommodated off-centre. Electrical wiring <NUM>, supply cables and pull wires <NUM> may instead be made with overlength and slack so as to be able so as to allow them to twist and wrap. Accordingly, the pull wires <NUM> are preferably in guide tubes 19a to provide Bowden cables. To accommodate for all these requirements, the present disclosure utilises a connection member <NUM>.

<FIG> shows the connection member <NUM> with a wall <NUM>. At the proximal end the connection member <NUM> comprises a section <NUM> where the wall is circumferentially closed. In this section <NUM>, an outer circumferential recess <NUM> adapted to accommodate sealing member <NUM>, preferably in the form of an O-ring of an elastomer material, is provided. The outer diameter of the uncompressed sealing member <NUM> is slightly larger than the inner diameter of a cylindrical bore <NUM> provided in the distal end of the Y-junction body <NUM>, so as to provide a seal allowing the connection member <NUM> to rotate with respect to the Y-junction body. The remainder of the wall <NUM> towards the distal end of the connection member <NUM> is not circumferentially closed. The wall <NUM> defining a through, but not circumferentially closed, passage between the proximal first end <NUM> and a distal second end <NUM>. Towards the distal second end <NUM> the connection member <NUM> comprises a slit <NUM> in the wall <NUM>. Between the slit <NUM> and the circumferentially closed section <NUM> of the wall <NUM> a larger opening <NUM> covering mostly half of the circumference is provided. As can be seen from the partial cross section of <FIG>, this larger opening serves as an exit opening for the electrical wiring <NUM>, supply cables and pull wires <NUM> covered with the guide tubes 19a.

During assembly of the endoscope the main tube 6a is inserted into the passage of the connection member <NUM> to the position shown in <FIG> where it is secured, preferably my means of an adhesive. During this insertion, the electrical wiring <NUM>, supply cables and pull wires <NUM> extending from the proximal end of the main tube <NUM> of the insertion cord assembly may easily be passed through the slit <NUM> so as to emerge laterally from the exit opening <NUM>, so that they will in the fully assembled endoscope pass around the outside of the Y-junction body inside the handle <NUM>. This can be done even if the electrical wiring <NUM> and supply cables have been joined to the printed circuit board <NUM> in the pre-fabrication of the insertion cord assembly, because the circuit board need not pass through the connection member <NUM>, and the electrical wiring <NUM> and supply cables need only pass the slit <NUM>. The proximal end of the working channel tube <NUM> is adhered to the inside of the section <NUM> where the wall is circumferential, so as to provide a sealed connection. For this, a glue hole <NUM> for introducing the adhesive may preferably be provided in the otherwise circumferential wall section <NUM>.

In order to ensure a smooth transition from the connection member <NUM> to the working cannel tube <NUM> the working channel tube <NUM> is preferably flared out at the proximal end. The smooth transition without edges is desirable to prevent procedure tools or optical fibres inserted through the Y-junction body <NUM> into the working channel <NUM> to be caught and disturbing the insertion process. For this a tool <NUM> as shown in <FIG>. The tool has a gripping part <NUM> for digitally gripping it with thumb, index finger and possibly middle finger when inserting it into the connection member <NUM> and the working cannel tube <NUM> as shown in <FIG>. The gripping portion <NUM> is preferably knurled or in other way prepared for good grip. The tool furthermore comprises an insertion section with a rounded distal insertion end <NUM>, a first cylindrical part <NUM> of a first diameter and a second cylindrical part <NUM> of second diameter. The first diameter is larger than the second diameter. A tapering section <NUM>, e.g. frusto-conical is provided between the second cylindrical part <NUM> and the first cylindrical part <NUM>.

As can be seen from <FIG> the frusto-conical section of the tool expands the working channel tube <NUM> and provides a flare in the transition area marked (with the circle F) which is maintained once the glue <NUM> has set. It also helps aligning the working channel tube with the bore of the connection member <NUM>.

The connection member <NUM> may then be inserted into a bushing <NUM>. The bushing is made of a low friction material such as POM. This is done by sliding the busing <NUM> over the insertion cord sub-assembly from the distal end and onto the connection member <NUM> where it clicks into position, as seen in <FIG>. POM is difficult to get adhesive to stick to and accordingly the connection member <NUM> and the bushing <NUM> comprise mutually interlocking features securing them with respect to each other in both the circumferential direction as well as in the longitudinal direction. Thus, as can be seen from <FIG> the distal end of the bushing <NUM> comprises two resilient arms <NUM> with inwardly extending protrusions <NUM> adapted to elastically snap into engagement with recesses <NUM> in the outer surface of the connection member <NUM>, thus mutually securing the connection member <NUM> and the bushing <NUM> with respect to another. To ensure the correct orientation in the circumferential direction, i.e. ensuring that electrical wiring <NUM>, supply cables and pull wires <NUM> are later at the correct side within the handle ribs, the inner bushing wall surface <NUM> is provides with a first rib <NUM> and a second rib <NUM> of differing widths, where the first rib <NUM> is adapted to engage in the slit <NUM> in the connection member <NUM> and the second rib <NUM> is adapted to engage into a groove preferably arranged diametrically opposite side of slit in the outer surface of the connection member <NUM> (not visible in the figures). This also further secures the connection member <NUM> and the bushing with respect to another in the circumferential direction.

To end correctly up in this correct orientation in the circumferential direction, the proximal part of the inner bushing wall surface <NUM> comprises a longitudinal groove <NUM> adapted to guide a protrusion <NUM> on a flange <NUM> on the connection member <NUM>, cf. When sliding the bushing <NUM> over the connection member the flange <NUM> abuts a stop wall <NUM> formed by a step covering a majority of the circumference of the inner wall surface <NUM>. The position of this stop wall <NUM> in the longitudinal direction is so selected that the inward extending protrusions <NUM> latch into the recesses <NUM> and secure the mutual position of the connection member <NUM> and the bushing <NUM> in the longitudinal direction. At the end of the stop wall <NUM> small protrusions <NUM> in the longitudinal direction are provided, so as to secure further the position of the connection member <NUM> with respect to the bushing <NUM> in the circumferential direction. For the remainder of the circumference, i.e. the minority part between the protrusions <NUM> the step is missing, so as to provide lateral space <NUM> for the wires protruding from the opening <NUM> in the connection member <NUM> in the assembled state.

The printed circuit board <NUM> with electrical wiring <NUM>, supply cables and pull wires <NUM> emerging from the opening <NUM> into the lateral space <NUM> and out of the proximal end of the bushing <NUM> may then be placed in housing part <NUM> using the slit <NUM> to pass the cables. A marker ring <NUM> may be slid over the end of the housing part <NUM>, snap into a recess <NUM> and partially close the slit <NUM>. More specifically the marker ring <NUM> may be slid from the distal end of the insertion cord sub-assembly over the bushing <NUM> to surround the coupling mechanism and preventing expansion of the slit <NUM> by forces from the busing <NUM>, thus later aiding in ensuring the desired amount of friction between the handle housing part <NUM> and the bushing <NUM>.

The bushing <NUM>, now connected to the insertion cord sub-assembly may then be inserted into the distal end of the handle housing now partially closed with the marker ring <NUM>. In this position the bushing is secured against axial movement by a flange <NUM> provided on the outer bushing wall surface <NUM>, and engaging the distal end surface <NUM> of the housing part <NUM>, and a C-shaped clip <NUM> engaging in a circumferential recess <NUM> in the outer surface of the bushing <NUM>. Protruding from the proximal end of the bushing <NUM> a stop member <NUM> is preferably provided. This stop member <NUM> is adapted to engage suitable uprights <NUM> on the interior surface of the housing part <NUM> to limit the rotation of the bushing <NUM> with respect to the handle <NUM>. The uprights <NUM> may preferably also serve as anchoring points for the Y-junction body <NUM>, i.e. points for adhering the Y-junction body <NUM> to the interior of the housing part <NUM>.

As mentioned, the bushing <NUM> is preferably made from a low friction material. To provide for good grip for the operator needing to turn the bushing <NUM> and the insertion cord <NUM> with respect to the handle <NUM>, an annular gripping member <NUM> is provided. The annular gripping member <NUM> has an external circumferential gripping surface <NUM> and an inner gripping member surface <NUM>. Preferably the external circumferential gripping surface <NUM> comprises a number of teeth <NUM>, <NUM> of which one tooth <NUM> preferably is higher than the others and/or provided with additional surface features <NUM> to provide the user with a sense of position. Like the other parts, the annular gripping member <NUM> is slid over the insertion cord sub-assembly from the distal end thereof.

The inner surface is preferably provided with longitudinal grooves <NUM> adapted to match external ribs <NUM> on the outer surface wall <NUM> of the bushing <NUM>, so as to ensure their correct mutual orientation when assembling the endoscope <NUM>, e.g. so as to have the tooth <NUM> extending correctly when in a neutral position with respect to the handle <NUM>. Thus, at least one first inner gripping member surface part in the form of the longitudinal grooves <NUM> is providing engagement with said outer bushing wall <NUM>.

Furthermore, a second inner gripping member surface wall part <NUM> is rotatably engaging the exterior of said housing part <NUM>. The second inner gripping member surface part <NUM> comprises at least one, but preferably two, position reference members, e.g. in the form of a notch 63a adapted to mutually engage complementary position reference members <NUM> on the exterior of the housing part <NUM>. Alternatively, the position reference member <NUM> on the exterior of the housing part <NUM> could be provided as a notch. The two position reference members are preferably located with a <NUM>° spacing, in particular with <NUM>° spacing from the tooth <NUM> on either side thereof. Similarly, the complementary position reference members <NUM> are located with a <NUM>° spacing on either side of the housing part <NUM>, in particular with <NUM>° spacing from the slit <NUM> on either side thereof. The complementary position reference members <NUM> are preferably provided on leaf spring members <NUM> provided at the distal end of the housing part <NUM>. The leaf spring members <NUM> may conveniently be formed integrally with the housing part <NUM> by provision of suitable circumferential slits <NUM> in the wall of the housing part <NUM>. When aligned the reference members with their complementary parts, under the spring force from the leaf spring members, keeping insertion cord 6b in position with respect to the handle <NUM> until a user's attempt to turn the insertion cord 6b provides a force overcoming the forces of the leaf spring members <NUM>.

To axially secure the annular gripping member <NUM> with respect to the bushing <NUM>, the distal end of the annual gripping member <NUM> comprises a pair of elastic latching members <NUM> with inward protrusions <NUM> adapted to engage a corresponding pair of recesses <NUM> in the outer surface of the bushing <NUM>.

Finally, to complete the assembly of the insertion cord sub-assembly to the handle <NUM> via the rotary coupling mechanism, a tension relief member <NUM> may be slid over the insertion cord <NUM> from the distal end thereof an onto the annular gripping member <NUM> to engage a generally circumferential ribs <NUM> at the elastic retaining members <NUM> on the distal end of the annular gripping member <NUM>. The tension relief member <NUM> not only serves as tension relief but inter alia serves as sealing cover for the coupling mechanism and as a holding means for e.g. an endotracheal tube during intubation of a patient or for a protective tubular cover during storage of the endoscope <NUM>, which may be held by a number of circumferential elastic ribs <NUM>.

Claim 1:
An endoscope (<NUM>) comprising a proximal handle (<NUM>) comprising a housing part (<NUM>) and a distal insertion cord (<NUM>) coupled to said proximal handle (<NUM>) by means of a rotary coupling mechanism allowing rotation about a rotation axis, said coupling mechanism comprising
a bushing (<NUM>) having a through aperture defining an inner bushing wall surface (<NUM>) adapted to receive a connection member (<NUM>) and an outer bushing wall surface (<NUM>) adapted to engage an inner handle surface in said handle (<NUM>),
a connection member (<NUM>) received in said through aperture and having a wall (<NUM>) defining a through passage between a first end (<NUM>) and a second end (<NUM>),
wherein said second end (<NUM>) is attached to an insertion cord sub-assembly, and said first end (<NUM>) is rotatably coupled to a working channel part (<NUM>) within said handle (<NUM>),
characterized in that a lateral exit opening (<NUM>) is provided in said wall (<NUM>) between said first end (<NUM>) and said second end (<NUM>) and
wherein a slit (<NUM>) is provided in said wall (<NUM>) from said second end (<NUM>) to said exit opening (<NUM>).